Method of dispersing and/or grinding and/or concentrating calcium carbonate in aqueous medium using aqueous solution containing zirconium compounds

FIELD: chemistry.

SUBSTANCE: suspension containing calcium carbonate is obtained by adding one or more zirconium compounds and possibly one or more other additives which do not contain phosphate, acting as a dispersant and/or an additive which assists in grinding. Calcium carbonate in dry form and/or in form of an aqueous dispersion or filtered residue is added an aqueous suspension and/or aqueous emulsion and/or aqueous solution containing one or more zirconium compounds. The zirconium compounds used is ammonium zirconium carbonate or calcium zirconium carbonate or mixture thereof.

EFFECT: invention enables to avoid the use of phosphate dispersants when preparing stable aqueous suspensions of calcium carbonate and increases content of solid substance in the suspension.

17 cl, 22 ex

 

The aim of the present invention is to provide a method of producing a suspension containing calcium carbonate, in which the specified suspension containing calcium carbonate, obtained by introducing one or more compounds of zirconium and possibly one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

Processing of minerals often requires the addition of water. The result is the formation of excessively diluted suspensions of minerals, so there is a need for concentration of fine-grained minerals in suspension for further processing. Depending on the desired final concentration of minerals used different methods of water removal. In addition to techniques such as centrifugation, filtration or evaporation, it is known that removal of water from suspensions can be carried out using electrophoresis or electro-osmosis methods, usually called electroencephalogram that lead to the formation of a solid layer or sludge.

In the private version of this method is characterized by the fact that it is a way of mixing, in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension of the/or aqueous emulsion, and/or an aqueous solution containing one or more compounds of zirconium, and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that he is a grinding method in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion or suspension in water or water filtered sludge is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or water plants the ora is introduced into the aqueous dispersion or aqueous suspension, or water filtered precipitate of calcium carbonate, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of dispersing, in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of concentrating, in which:

carbonate to Lycia in dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is concentrated possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding, or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is concentrated possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of dispersing, in which:

the calcium carbonate pigment sludge, such as precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya (and specified residue preferably has a moisture content above 20% by dry weight of mineral matter), is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and get the song dispersed possibly with one or more other additives, contains no phosphate, acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the pigment residue, such as precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya (and specified residue preferably has a moisture content above 20% by dry weight of mineral matter), and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

Another objective of the present invention is to provide a method of producing aqueous suspensions and/or aqueous dispersions of stable viscosity of the calcium carbonate without using well-known phosphate dispersant, which, as now considered, are environmental pollutants.

Also the aim of the present invention is to provide a method of producing aqueous suspensions and/or aqueous dispersions of stable viscosity of the calcium carbonate, in which the total number of polycarboxylates, such as polyacrylates or maleate and/or combinations thereof, is reduced when they are used as dispersing agents, because they are the descendants of petrochemical products, contributing to the increase in "total organic carbon" (TOC)(TOC)in the atmosphere and dissolved organic carbon (DOC)(DOC)in the water. The Kyoto Protocol on 11 December 1997, helps preserve the environment by stabilizing and reduce emissions of greenhouse gases, reducing climate change and contributing to long-term environmental quality. The Kyoto Protocol recognizes the importance of regulation and reduce emissions of greenhouse gases, which are currently primarily from industrial and transportation sources; the Protocol also recognises the related opportunities, which should be increased by better management of carbon pools and improvement of carbon sinks in forestry and agriculture.

Also the aim of the present invention is to provide a method of producing aqueous suspensions and/or aqueous dispersions of stable viscosity of the calcium carbonate, which can have a high solids content of more than 45% by dry weight of mineral matter, perhaps more than 65% by dry weight of mineral matter, and perhaps more than 78% by dry weight of mineral matter, or who can provide a suspension containing calcium carbonate obtained from stage mechanical and/or thermal reconcentration following, less the least one stage of dry and/or wet grinding without the use of dispersant and at low concentration relative to dry matter (less than 40% by dry weight of mineral matter), and, optionally, with the subsequent stage of grinding in concentration to form a high solids content of more than 45% by dry weight of mineral matter, perhaps more than 65% by dry weight of mineral matter, and perhaps more than 78% by dry weight of mineral matter.

Also the aim of the present invention is to provide a method of producing such stable aqueous suspensions and/or aqueous dispersions of calcium carbonate possibly in the form of a high content of solids, and aqueous suspensions and/or dispersions retain and/or improve the optical properties, notably retain and/or increase the opacity and/or dissipation factor of the final product when used in such ready-to-use recipes.

Thus obtained aqueous slurry and/or aqueous dispersions are also subject of the present invention.

Another object of the present invention is a dry mineral pigment calcium carbonate obtained after drying the above aqueous suspensions and/or aqueous dispersions.

Another objective of the present invention is the application of the decree is the R of aqueous suspensions and/or aqueous dispersions, and/or dry mineral pigments calcium carbonate in obtaining paper and/or paper coatings, and/or polymer coatings, as fillers for polymers or compositions of water paints, etc.

The last object of the present invention is paper, polymers and paints containing such water dispersion and/or aqueous suspensions and/or dry mineral pigments calcium carbonate.

Water dispersion and/or aqueous suspensions and/or dry mineral pigments calcium carbonate mineral substances currently used in various applications, and, in particular, when the content of calcium carbonate as inorganic dispersed material they are especially used to produce compositions containing pigments or fillers, which can then be used in obtaining paper and/or paper and/or polymer coatings, as fillers for polymers or compositions of water paints, etc.

In order to maintain such suspension in a stable form in terms of viscosity and to avoid such undesirable phenomena as aggregation, occulation or sedimentation, in the process of receiving, transportation or storage of the suspension, a specialist in the art knows that it is necessary to obtain a stable aqueous suspensions and/or aqueous dispersion of dispersedechelle with the use of dispersing agents and/or additives, improving grinding. It is also well known that the choice of such dispersing agents and/or additives that improve the grinding may later influence some of the characteristics of the final products made on these suspensions; for example, in the case of formulations of water paints, paper or paper coating existing techniques include documents relating to the dispersing agents which improve the optical properties of the final products, such as opacity, gloss or dissipation factor.

US 5043017 and US 5156719 consider fine calcium carbonate, which is cyclotetramethylene by using the calcium-chelating agent conjugate base, such as polyphosphates and a weak acid, the latter is, preferably, phosphoric acid, and method for producing such a calcium carbonate and the paper containing such calcium carbonate.

These decisions are not consistent with the new requirements for the specialist in the art in terms of the use of certain chemicals, which are now considered potential contaminants of sewage and industrial waters, namely, phosphate compounds. Indeed, chemical products containing phosphates, currently have increased the number of restrictions. In the spring of 2003, the European Union has published a Protocol for the category is Yu release and transfer of pollutants. 7 October 2004 the European Commission adopted a plan for the settlement of future commitments: COM (2004) 634. Annex I of this plan contains a list of industrial facilities and institutions for consideration: the mining industry can be found on page 25 (underground mining and related operations, open pit mining). Annex II contains a list of 90 products for consideration: on page 28 specified total phosphorus.

Due to these previous decisions, considering the use of phosphates and primarily phosphoric acid, can not be considered effective and used to a person skilled in this technical field.

Known for many years in engineering, another solution to obtain stable suspensions of mineral substances is the use of acrylic homopolymers and/or acrylic copolymers with other water-soluble monomers. FR 2603042, EP 0100947, EP 0127388, EP 0129329, EP 0542644 consider the use of such polymers having low molecular weight, for this purpose. Although these different types of dispersant makes it possible to obtain aqueous suspensions of micronized minerals that are stable over time, they do not provide the subsequent suspension or re-dispersion of mineral matter in water, t is anyone as particularly calcium carbonate, when receiving from the stage of mechanical and/or thermal reconcentration following stage of dry and/or wet grinding without the use of dispersant and at low concentration relative to dry matter (less than 40% by dry weight) and, optionally, with the subsequent stage of grinding. This low solid ground calcium carbonate, crushed in water suspension using any dispersant and/or additives, which improve the grinding is difficult to disperse with the formation of suspensions with high solids content.

Faced with this problem, a specialist in the art meets WO 0148093, which describes the choice of homopolymers of acrylic acid and/or water-soluble copolymers of acrylic acid with high molecular weight (corresponding to a viscosity index in the range from 0.08 to 0.80). Another solution is proposed in EP 0850685, which considers the use of water-soluble copolymer of acrylic acid and maleic acid in a ratio in accordance with a specific molecular weight.

However, the above-mentioned polymers and copolymers derived from petrochemical compounds, which are known to contribute to an undesirable increase in TOC in the atmosphere and ROWE in the water and not consistent skiscim Protocol, as indicated here above.

In addition, none of these documents describes the impact of dispersant used on the final properties of the aqueous formulations containing a suspension of mineral substances obtained in accordance with these inventions, and, in particular, no one does not consider the possible improvement of the optical properties of the ink, or paper, or paper coatings, poluchennyh with the use of such suspensions; the present invention enables a person skilled in the art to meet the requirements of the end use in terms of preserving or improving the optical properties of the final products.

In addition, as noted in this application, the method according to the present invention additionally allows to reduce the number polycarboxylate dispersant with achievement of the specific viscosity by the Brookfield when using in combination with a compound of zirconium. In combination with the polyacrylate dispersant use of compounds of zirconium according to the present invention leads to excellent results in terms of stability and content of the solids re-dispersed suspensions of calcium carbonate, which are unexpectedly equivalently or even improved compared with that obtained according to WO 0148093 and EP 0850685, and leads to a decrease ROW and highlight iskopaemogo CO 2during the decomposition of the dispersant with respect to the suspensions obtained according to the above-mentioned patents.

Thus, solving the technical problem can be summarized as follows: a specialist in the art should strictly avoid the use of phosphate and should reduce the number of polycarboxylate required for a given degree of dispersion in aqueous suspensions and/or aqueous dispersions of mineral matter due to more restrictive regulations; in addition, he must also develop a way to concentrate the mineral substance; according to the specified standards he must also develop a way of re-dispersion of calcium carbonate obtained from stage mechanical and/or thermal reconcentration, following after at least one stage of dry and/or wet grinding without the use of dispersant and at low concentration relative to dry matter; finally, he must fulfill the requirements of the end use and must maintain or improve the part of the optical properties of the final products, such as opacity.

Taking into account the mentioned technical problem was unexpectedly found a new way of obtaining such aqueous suspension of calcium carbonate.

The method is to obtain a suspension, steriade is calcium carbonate, in which the specified suspension containing calcium carbonate, obtained by introducing one or more compounds of zirconium and possibly one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In the private version of this method is characterized by the fact that it represents the blending method in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that he is a grinding method, in the cat the rum:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion or suspension in water or water filtered sludge is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of dispersing, in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate, applicable to the to the dispersant and/or additive, conducive to grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of concentrating, in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is concentrated possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is concentrated possibly with one or more other additives, the e containing phosphate, acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of dispersing, in which:

the calcium carbonate pigment sludge, such as precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya (and specified residue preferably has a moisture content above 20% by dry weight of mineral matter), is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the pigment residue, such as precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya (and specified residue preferably has a moisture content above 20% by dry weight of mineral matter), and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or the additive, facilitate grinding.

It should be noted that the thus obtained aqueous suspension can be further concentrated to a higher concentration method, well known to the person skilled in the technical field, such as the use of a centrifuge or evaporator, and that during this stage, additional concentration can be entered an additional amount of calcium carbonate in a dry form (powder) or in suspension (suspension in water).

The resulting aqueous suspensions are very stable in terms of viscosity according to Brookfield, on the one hand. On the other hand, they allow a person skilled in the art to provide the end user with highly concentrated suspensions of mineral substances, which are easily pumped by the pump and easy flow, and/or concentrated suspensions with low solids content to form a higher content of solids (containing more than 45% by dry weight of mineral matter, perhaps more than 65% by dry weight of mineral matter, and perhaps more than 78% by dry weight of mineral matter). In addition, they allow you to completely avoid the use of dispersant containing phosphate compounds. They also contribute to the reduction does not meet the requirements of The Kyoto Protocol on carboxylated dispersant and/or additives, improving grinding when they are used in the present invention. Finally, water the recipe and especially the formulation of paper and paper coatings containing such aqueous suspensions show equal or superior optical properties, especially in terms of opacity and/or dissipation factor.

It should be noted that such aqueous solutions containing zirconium compounds, well known in the art for many years, especially with regard to their use as crosslinking agents in aqueous formulations of coatings, as discussed in “Zirconium compounds find new uses in surface coatings” (Modern paint and coatings, Febrary 1988, pp. 36-39). The fact that the polymer particles of zirconium can interact with the functional groups of organic polymers makes them more interesting for aqueous paints and coatings, where they can improve the heat resistance and the resistance to scratching, as stated in the article “Zirconium compounds in waterbased coatings (Polymer paint colour Journal, March 9, 1988, 178, 4209, pp. 154-162), and especially in the case of Bacote 20 ((Outlook addon) ACC - ammunitionsarsenal) and Zirgel K ((KZC) CCC - colitiscondition), produced by Magnesium Electron Ltd. A fully established that some of these compounds can be used in formulations of paints applied by spray, where they can influence the rheological, optical and printing properties of these paints. Decree the main results are considered relatively zirconiabased ((CC)(ZAA)and the ACC in the article “Influence of cationic additives on the rheological, optical and printing properties of ink-jet coatings (Polymer paint colour Journal, March 9, 1988, 178, 4209, pp. 154-162). However, each of these documents refers to the use of compounds of zirconium in aqueous formulations containing organic polymers (mainly, binders, which are strongly bound to the above compounds of zirconium), which is completely different from the present invention, which is considering the reduction of the use or exclusion of organic polymers, in particular of polycarboxylates used as additives promoting grinding or dispersing agents in aqueous suspensions of calcium carbonate.

Finally, although they cannot be regarded as definitely being in the scope of the present invention, because they do not address the requirements of the specialist in the art to completely avoid the use of phosphate compounds, providing a stable suspensions with high solids content of more than 45% by dry weight of mineral matter, perhaps more than 65% by dry weight of mineral matter, and perhaps more than 78% by dry weight of mineral matter, preserving and/or improving the optical properties of the final products and to lower TOC values for equal dispersion of calcium carbonate, the following documents are specified, as they consider use the W compounds of zirconium in aqueous suspensions of mineral substances, not containing organic polymers, and the improvement of the optical properties of the final products, such as paper and paper coatings.

In the US 3597251 indicates that either zinc oxide or zirconium oxide, or a mixture thereof can be used to improve the dispersion of calcium carbonate in water, which results in a solids content of from 55 to 80% by dry weight of mineral matter; however, the use of the above products is limited to the combination with the phosphate dispersant, as described in paragraph 1 of the claims.

EP 0206837 considers a method of producing pigment clay with sufficient amount of the ion source of zirconium to improve the optical properties of bases containing the pigment. The ACC is considered as one of the most effective sources of zirconium ion to improve the degree of whiteness, opacity and scattering coefficient of paper, receptorligand according to this invention. However, taking into account the above examples, it is clear that in order to obtain suspensions with high solids content (greater than 60% by dry weight of mineral matter), should be used in conventional phosphate-containing dispersing agents (see Example 1, page 12); the higher the concentration of ACC, the higher the optical properties, the lower the dispersibility of mineral cha the TIC (see Example 2, p. 15).

Thus, the specialist in the art will undoubtedly concludes from these documents that, although zirconium compounds can be used for dispersion of minerals, such as clay, and can be obtained in highly concentrated suspensions, requiring, however, the use of phosphate-containing dispersant, the dispersibility of minerals decreases; in connection with the new requirements relating to pollution in the mining industry, this is exactly what he wants to avoid.

Thus, in order to a person skilled in the art to meet a number of requirements: first of all, avoid the use of phosphate-containing dispersant and to minimize the number polycarboxylate dispersant and additives that grinding to obtain stable suspensions of calcium carbonate with a high content of solids (containing more than 78% by dry weight of mineral matter) and/or for concentration of dilute suspensions of calcium carbonate in the form of a high solids content (greater than 50% by dry weight of mineral matter, preferably more than 65% by dry weight of mineral matter, most preferably, more than 75% on a dry weight of mineral matter) and to maintain or possibly improve optical the properties (such as increased opacity and/or dissipation factor) of the final products, it was unexpectedly found a new way of receiving such suspension containing calcium carbonate.

This method is to obtain a suspension containing calcium carbonate, in which the specified suspension containing calcium carbonate, obtained by introducing one or more compounds of zirconium and possibly one or more additives that do not contain phosphate acting as a dispersant or additive that promotes grinding.

In the private version of this method is characterized by the fact that it is a way of mixing, in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate, applicable to the to the dispersant and/or additive, facilitate grinding.

In another embodiment, this method is characterized by the fact that he is a grinding method in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion or suspension in water or water filtered sludge is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of dispersing, in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more soy is ineni zirconium, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of concentrating, in which:

calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is concentrated possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding, or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspe is the Zia, or water filtered precipitate of calcium carbonate, and the resulting composition is concentrated possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

In another embodiment, this method is characterized by the fact that it is a way of dispersing, in which:

the calcium carbonate pigment sludge, such as precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya (and specified residue preferably has a moisture content above 20% by dry weight of mineral matter), is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,

or

one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the pigment residue, such as precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya (and specified residue preferably has a moisture content above 20% by dry weight m is the mineral substances), and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

Preferably, the method according to the present invention differs in that a compound of zirconium is ACC, CCC or mixtures thereof.

It also differs in that the compound of zirconium is served in the form of an aqueous solution and/or suspension containing from 0.01 to 10% by dry weight of zirconium compounds, more preferably from 0.03 to 5% by dry weight of zirconium compounds.

According to the invention can be used in industrial zirconium compounds. Non-limiting examples of such compounds are:

connection ACC type brand Bacote, manufactured by MEL CHEMICALS,

connection CCK type brand Zirmel manufactured by MEL CHEMICALS.

The method according to the present invention is characterized by the fact that these aqueous suspensions and/or aqueous dispersions containing calcium carbonate, obtained at the stage of mechanical and/or thermal reconcentration, following after at least one stage of dry and/or wet grinding without the use of dispersant and at low concentration relative to dry matter (less than 40% by dry weight) and, optionally, with the subsequent stage of grinding.

This is a procedure characterized by that the resulting aqueous suspensions and/or aqueous dispersion of calcium carbonate contain more than 45% by dry weight of calcium carbonate, preferably more than 65% by dry weight, and most preferably more than 78% by dry weight.

Another subject of the invention are aqueous suspensions and/or aqueous dispersion of calcium carbonate, characterized in that they are obtained by the method according to the present invention.

Such aqueous suspensions and/or aqueous dispersions are characterized in that they contain one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

More preferably, such aqueous suspensions and/or aqueous dispersions are characterized in that a compound of zirconium are the ACC, or CCC, or mixtures thereof.

Such aqueous suspensions and/or aqueous dispersions also differ in that they can be obtained at the stage of mechanical and/or thermal reconcentration, following after at least one stage of dry and/or wet grinding without the use of dispersant and at low concentration relative to dry matter (less than 40% by dry weight) and, optionally, with the subsequent stage of grinding.

Such aqueous suspensions and/or aqueous dispersions also differ in that they can contain more than 45% by dry mass of the spacecraft is of Bonita calcium, preferably, more than 65% by dry weight, and most preferably more than 78% by dry weight.

Another subject of the invention are aqueous formulations, characterized in that they contain aqueous suspensions and/or dispersions of calcium carbonate according to the present invention.

Another object of the present invention is a dry mineral pigment calcium carbonate obtained after drying these aqueous suspensions and/or aqueous dispersions.

Another object of the present invention is the application of the said aqueous suspensions and/or aqueous dispersions and/or dry pigments calcium carbonate in obtaining paper and/or paper and/or polymer coatings, as fillers for plastics or for compositions of water paints, etc.

The last object of the present invention is paper, plastics and paints containing such water dispersion and/or aqueous suspensions and/or dry mineral pigments calcium carbonate.

Further examples can help the specialist in the art to understand the invention according to this application, but should not be construed as limiting.

Examples

Note

All viscosity by Brookfield"in the following text refer to the viscosity by Brookfield measured using equipment supplied under the same name, at 100 rpm using module # 3.

Example 1

This example shows the use of zirconium compounds in a method of producing a suspension containing calcium carbonate, without the use of phosphate dispersant.

More precisely, it shows the use of zirconium compounds in a method of producing a suspension containing calcium carbonate, when the dispersion of calcium carbonate in water, and then the concentration without the use of phosphate dispersant.

Experiment No. 1

This experiment illustrates the invention.

450 g of a powder of calcium carbonate, manufactured by OMYA under the trademark Millicarb OG, suspended in 249 g of water.

The suspension has a solids content of 64% (by dry weight of mineral matter) and viscosity by Brookfield equal 1730 MPa·S.

After the introduction 0,70% dry weight of active additive ( by dry weight of mineral matter) Zirmel 1000, which is a compound of salicylaldiminato manufactured by MEL CHEMICALS, get a stable suspension of calcium carbonate with a viscosity according to Brookfield, equal to 40 MPa·S. No acrylate polymer or phosphate is not used and not required for the specified reduce the viscosity.

The resulting slurry is then concentrated using a laboratory evaporator with the addition of 0.39% dry matter active the additive (by dry weight of mineral matter) Zirmel 1000.

The final solids content is 76,0% (by dry weight of mineral matter), and the suspension has a stable viscosity by Brookfield equal to 170 MPa·S. No acrylate polymer or phosphate is not used and is not required to achieve the specified concentration of 76% solids when indicated significantly low viscosity.

The above result shows dispersing action CCK.

Example 2

This example shows the use of zirconium compounds in combination with a dispersant policealna type (and these polyacrylate dispersant type are introduced before or during the introduction of the zirconium compounds) in the production method of the suspension containing calcium carbonate, using as source material the filter cake or dry powder of calcium carbonate and avoid the use of phosphate to maintain dispersant.

More precisely, it refers to the use of zirconium compounds in combination with polyacrylate dispersant type dispersion method and in one case for additional concentrate filter cake or dry powder of calcium carbonate.

Finally, he shows that the use of the method according to the present invention provides a dispersion of calcium carbonate with good stability in terms of wascott is in Brookfield and makes it possible to reduce the number of required polyacrylate dispersant at the same solids content.

For Example 2 and samples to determine dissolved organic carbon(DOC)(DOC)) two dispersers, representing the prototype of the polymer natriolienate and the copolymer natiolialist/nutriment, which is respectively 14.6% (calculated on dry substance) and 11.7% (calculated on dry substance).

The above determination is performed by using a device supplied by the company DR LANGE under the name of LCK 386. The principle of determining based on the two-stage process in which the total inorganic carbon is first removed by means of a vibrator, and total organic carbon is then oxidized to carbon dioxide.

Carbon dioxide is passed through the membrane in the indicator cell, where it causes the color change, which is measured by the photometer.

For Example 2 and samples DOC (dissolved organic carbon) is calculated for each experiment based on the comparative values of the net dispersant mentioned above.

Experiment No. 2

This experiment illustrates the prototype.

Use filtered precipitate of calcium carbonate (based on the Norwegian marble with a solids content of 65% by dry weight of mineral matter and with the following particle size characteristics (as defined by the device Sedigfaph 5100):

- the average diameter of 0.63 µm,

- 92% wt. particles having an average diameter of less than 2 μm,

- 71% wt. particles having an average diameter less than 1 μm,

- 11% wt. particles having an average diameter of less than 0.2 microns.

This material was dispersed using 0,70% active dry additives (by dry weight of mineral matter) of the dispersant based on natiolialist/nativespace, which is a mixture of partially neutralized natriolienate (molecular weight MW equal to 12000 daltons, determined by the GPC method) and phosphates of sodium, obtained by blending 40% of natriolienate and 85% of solid phosphoric acid in the ratio 2:1 with respect to active dry mass of each Supplement.

The resulting slurry is then concentrated using a laboratory evaporator.

The final solids content is 72,5% by dry weight of mineral matter, and viscosity according to Brookfield, measured at 100 rpm and 125 MPa·s Content Nationalrat is 0.47% of the dry weight of the polymer by dry weight of mineral matter.

The value of the ROW is 0.10%.

Experiment No. 3

This experiment illustrates the prototype.

Use the same filtered precipitate of calcium carbonate, as in Experiment # 2, but when the content of 70% active solids (molecular weight MW equal to 12000 daltons, is definitely the GPC method) by dry weight of mineral matter.

The suspension obtained has a viscosity according to Brookfield, measured at 100 rpm above 1000 MPa·S.

Is ROWE 0,26%

Experiment No. 4

This experiment illustrates the prototype.

Use filtered precipitate of calcium carbonate (marble, Vermont) with a solids content of 61% by dry weight of mineral matter and with the following particle size characteristics (as defined by the device Sedigfaph 5100):

- the average diameter of 0.71 μm,

- 90% wt. particles having an average diameter of less than 2 μm,

- 64% wt. particles having an average diameter less than 1 μm,

- 7% wt. particles having an average diameter of less than 0.2 microns.

This material was dispersed using 0,70% active dry additives (by dry weight of mineral matter) of the copolymer natiolialist/nutriment (molecular weight MW equal to 12000 daltons, determined by the GPC method, and the molar ratio (acrylic acid):(maleic acid)=7:3) (active content by dry weight of mineral matter), and concentrate to 71.7% of solids.

The suspension obtained has a viscosity according to Brookfield, measured at 100 rpm, equal to 230 mPas

The resulting suspension additionally concentrate to 73,1% solids with the introduction of an additional 0.2% of the dry pigment on General introduction of 0.9% wt. the same copolymer is trimolecular/nutriment.

The suspension obtained has a viscosity according to Brookfield, measured at 100 rpm, equal to 260 mPas

Further concentration is impossible without the use of more than 1% of the same organic polymer by dry weight of mineral matter.

The value of the ROW is 0.37%.

Experiment No. 5

This experiment illustrates the prototype.

1812 powder of calcium carbonate, manufactured by OMYA under the trade name Hydrocarb 90-OG, suspended in 499 g of water.

The suspension has a solids content of 78,3 (by dry weight of mineral matter and viscosity according to Brookfield, equal 605 mPas

Experiment No. 6

This experiment illustrates the invention.

The same filtered precipitate of calcium carbonate as used in experiment No. 2 was dispersed using a combination of:

- 0,26% natriolienate (molecular weight Mw equal to 12000 daltons, measured by the GPC method, as used in experiment No. 3), active content by dry weight of mineral matter,

- 0,258% dry weight of active additive by dry weight of mineral matter connection ammoniacarbonate manufactured by MEL CHEMICALS under the trademark Bacote 20.

The resulting slurry is then concentrated using a laboratory evaporator.

The final solids content of suspense the carbonate makes 75.5% by dry weight of mineral matter, and viscosity according to Brookfield, measured at 100 rpm, is 390 MPa·C. Even at such a high solids content natriolienate can be reduced by about one-third only to 0.26% in comparison with Experiment No. 3.

The value of the ROW is of 0.075%. This value is lower than values obtained for Experiments No. 2, 3 and 4: as such, the method according to the present invention enables a person skilled in the art to significantly reduce the value of the ROW at a comparable or even higher solids content.

Experiment No. 7

This experiment illustrates the invention.

The same filtered precipitate of calcium carbonate as used in Experiment No. 2 was dispersed using a combination of:

- 0,26% natriolienate (molecular weight Mw equal to 12000 daltons, measured by the GPC method, as used in experiment No. 3), active content by dry weight of mineral matter,

- 0,28% dry weight of active additive by dry weight of mineral matter connection salicylaldiminato manufactured by MEL CHEMICALS under the trademark Zirmel 1000.

The resulting slurry is then concentrated using a laboratory evaporator.

The final solids content is to 72.6% by dry weight of mineral ve is esta, and viscosity according to Brookfield, measured at 100 rpm and 460 MPa·S.

The value of the ROW is of 0.075%. This value is lower than values obtained for experiments No. 2, 3 and 4; as such, the method according to the present invention enables a person skilled in the art to significantly reduce the value of the ROW using various zirconium compounds compared with Experiment No. 6.

Experiment No. 8

This experiment illustrates the invention.

The same filtered precipitate of calcium carbonate as used in Experiment No. 2, adjusted to the solids content of 53% by dry weight of mineral matter, is dispersed using a combination of:

- 0,34% natriolienate (molecular weight Mw equal to 12000 daltons, measured by the GPC method, as used in experiment No. 3), active content by dry weight of mineral matter,

- 0,52% of the dry weight of the polymer by dry weight of mineral matter connection salicylaldiminato manufactured by MEL CHEMICALS under the trademark Zirmel 1000.

The resulting slurry is then concentrated using a laboratory evaporator.

The final solids content is 74,1% by dry weight of mineral matter, and viscosity according to Brookfield, measured at 100 rpm, is 255 the PA·S.

The above results show that it can be atomized calcium carbonate according to the present invention when using zirconium compounds in combination with the polyacrylate dispersant, avoiding, thus, the use of phosphate dispersant.

In addition, they show that it is possible to achieve a high content of solids compared to the prototype and preserving the stability of the obtained aqueous suspension in terms of viscosity by Brookfield.

Finally, for similar viscosity by Brookfield and higher content of solids the above results show that the method according to the present invention reduces the required number of polyacrylate dispersant.

The value of the ROW is of 0.075%. This value is lower than values obtained for Experiments No. 2, 3 and 4; as such, the method according to the present invention enables a person skilled in the art to significantly reduce the value of the ROW.

Experiment No. 9

This experiment illustrates the invention.

The same filtered precipitate of calcium carbonate as used in Experiment No. 2, adjusted to the content of solid substances of 20% by dry weight of mineral matter, is dispersed using a combination of:

- 0,34% natriolienate (with mo is collaroy mass Mw, equal to 12,000 daltons, measured by the GPC method, as used in Experiment No. 3), active content by dry weight of mineral matter,

- 0,52% of the dry weight of the polymer by dry weight of mineral matter connection salicylaldiminato manufactured by MEL CHEMICALS under the trademark Zirmel 1000.

The resulting slurry is then concentrated using a laboratory evaporator.

For the following values of the content of solids obtain a stable suspension of calcium carbonate with the following values of the viscosity by Brookfield:

- when 69,6% solids (by dry weight of mineral matter) receive viscosity by Brookfield 395 MPa·s,

- when 71,7% solids (by dry weight of mineral matter) receive viscosity by Brookfield 480 MPa·s,

- when 75,1% solids (by dry weight of mineral matter) receive viscosity by Brookfield 800 MPa·S.

The above results show that the method of using a compound of zirconium according to the present invention, allows the filtered precipitate of calcium carbonate with low solids concentration to form a high solids content.

In addition, the resulting suspension according to the present invention remain stable in terms of viscosity by Brookfield.

The value of the ROW is 0.11%. D. the TES value is lower than the values obtained for Experiments No. 2, 3 and 4; as such, the method according to the present invention enables a person skilled in the art to significantly reduce the value of the ROW.

Experiment No. 10

This experiment illustrates the invention.

By 1981, the suspension of experiment No. 5 add 0,084% dry weight of active additive (by dry weight of mineral matter) Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato.

The resulting suspension of calcium carbonate has a solids content of 78,3% (by dry weight of mineral matter) and viscosity by Brookfield 255 MPa·S.

To 1636 suspension 3D add 0,359% dry weight of active additive (by dry weight of mineral matter) Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato.

Get a very stable suspension of calcium carbonate with solids to 78.3% (by dry weight of mineral matter) and viscosity Brookfield 215 MPa·S.

The above results show dispersing action CCK.

Example 3

This example shows the use of zirconium compounds in a method of producing a suspension containing calcium carbonate.

More precisely, it refers to the use of zirconium compounds in the way ismale the Oia of calcium carbonate.

Finally, he shows that the use of zirconium compounds as additives to facilitate grinding, and as a dispersant according to the present invention provides a suspension of powdered calcium carbonate with a high content of solids with good stability in terms of viscosity by Brookfield.

Experiment No. 11

The suspension of calcium carbonate 56% of the dry weight of mineral matter ground in water using an additive Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato.

Then determine the particle size distribution of particles using a device Sedigraph 5100 supplied by the company MICROMERITICS, as a function of the quantity of the zirconium compounds:

- when using 0,38% (by dry weight of mineral matter) Zirmel 1100 24% (by weight of mineral matter) of particles has an average diameter of less than 1 μm,

- when using 0,69% (by dry weight of mineral matter) Zirmel 1100 36% (by weight of mineral matter) of particles has an average diameter of less than 1 μm,

- when using 1,28% (by dry weight of mineral matter) Zirmel 1100 50% (by weight of mineral matter) of particles has an average diameter of less than 1 μm,

- when using 3,80% (by dry weight of mineral matter) Zirmel 1100 75% (by weight of mineral matter) of particles has an average is iameter less than 1 micron.

The above results show that the method according to the present invention enables a person skilled in the art to grind calcium carbonate in the water to the desired level of fineness without the use of phosphate or polyacrylate compounds.

Example 4

This example shows the use of zirconium compounds in combination with polyacrylate dispersant type in a method of producing a suspension containing calcium carbonate, while avoiding the use of phosphate to maintain dispersant.

More precisely, it refers to the use of zirconium compounds in combination with polyacrylate dispersant type in the way that the dispersion and concentration of calcium carbonate.

Finally, he shows that the use of the method according to the present invention gives a stable dispersion of calcium carbonate in terms of viscosity by Brookfield and reduces the amount of polyacrylate dispersant required for viscosity.

Experiment No. 12

This experiment illustrates the prototype.

Get 1 m3suspension of the calcium carbonate content of 72.6% solids with the following particle size characteristics (as measured with Sedigraph 5100):

- the average diameter of 0.80 μm,

- 88% wt. particles have an average diameter of less than 2 μm,

- 61% mA is. particles have an average diameter of less than 1 μm,

- 8% wt. particles have an average diameter of less than 0.2 microns.

The above suspension is obtained from the aqueous suspension of calcium carbonate with a solids content of 18.7% by dry weight of mineral matter in the use of 0.35% of the dry weight of active additive (by dry weight of mineral matter) of the dispersant based natriolienate/nativespace, which is a mixture of partially neutralized natriolienate (molecular weight Mw equal to 12000 daltons, measured by the GPC method) and nativespace, obtained by blending 40% of natriolienate and 85% of solid phosphoric acid in the ratio 2:1 with respect to active dry mass of each Supplement.

The suspension obtained when thermal concentration using a pilot evaporator.

The final solids content of the suspension of calcium carbonate is to 72.6% by dry weight of mineral matter, and viscosity according to Brookfield, measured at 100 rpm and 200 MPa·S.

The value of the ROW is 0,062%.

The content of trisodium phosphate (Na3PO4in the sample relative to the dry weight of mineral matter is 0.20%.

Experiment No. 13

This experiment illustrates the prototype.

Get 1 m3suspension of calcium carbonate with a high solids content, the substances with the following particle size characteristics (as measured with Sedigraph 5100):

- the average diameter is 0.61 μm,

- 94% wt. particles have an average diameter of less than 2 μm,

- 73% wt. particles have an average diameter of less than 1 μm,

- 14% wt. particles have an average diameter of less than 0.2 microns.

The above suspension is obtained from the aqueous suspension of calcium carbonate with a solids content of 18.7% by dry weight of mineral matter in the use of 0.68% dry weight of active additive (by dry weight of mineral matter) of the dispersant based natriolienate/nativespace, which is a mixture of partially neutralized natriolienate (molecular weight Mw equal to 12000 daltons, measured by the GPC method) and nativespace, obtained by blending 40% of natriolienate and 85% of solid phosphoric acid in the ratio 2:1 with respect to active dry mass of each Supplement.

The suspension obtained when thermal concentration using a pilot evaporator.

The final solids content of the suspension of calcium carbonate is 72,3% by dry weight of mineral matter, and viscosity according to Brookfield, measured at 100 rpm, is 248 MPa·S.

The value of the ROW of 0.125%.

The content of trisodium phosphate (Na3PO4in the sample relative to the dry weight of mineral matter is 0,40%.

Experiment No. 14

This experiment Fig is helpful invention.

Get 1 m3suspension of calcium carbonate with a high content of solids with the following particle size characteristics (as measured with Sedigraph 5100):

- the average diameter of 0.86 micron,

- 89% wt. particles have an average diameter of less than 2 μm,

- 59% wt. particles have an average diameter of less than 1 μm,

- 6% wt. particles have an average diameter of less than 0.2 microns.

The above suspension is obtained from the aqueous suspension of calcium carbonate with a solids content of 22.0% by dry weight of mineral matter using 0,22% dry weight of active additive (by dry weight of mineral matter) of natriolienate (molecular weight Mw equal to 12000 daltons, measured by the GPC method) and 0.23% Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato.

The suspension obtained when thermal concentration using a pilot evaporator.

The final solids content of the suspension of calcium carbonate is 71.2% by dry weight of mineral matter, and viscosity according to Brookfield, measured at 100 rpm, 440 MPa·S.

The value of the ROW is 0,062%.

The phosphate content in this example of the invention in comparison with Experiment No. 12 can be completely excluded.

Experiment # 15

This experiment illustrates sabreena.

Get 1 m3suspension of calcium carbonate with a high content of solids with the following particle size characteristics (as measured with Sedigraph 5100):

- the average diameter of 0.69 μm,

- 94% wt. particles have an average diameter of less than 2 μm,

- 72% wt. particles have an average diameter of less than 1 μm,

- 7% wt. particles have an average diameter of less than 0.2 microns.

The above suspension is obtained from the aqueous suspension of calcium carbonate with a solids content of 17.8% by dry weight of mineral matter using 0,28% dry weight of active additive (by dry weight of mineral matter) of natriolienate (molecular weight Mw equal to 12000 daltons, measured by the GPC method) and 0.26% Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato.

The suspension obtained when thermal concentration using a pilot evaporator.

The final solids content of the suspension of calcium carbonate is 71.2% by dry weight of mineral matter, and viscosity according to Brookfield, measured at 100 rpm, is 840 MPa·S.

After the introduction of an additional 0.1% of Zirmel 1000 viscosity by Brookfield, measured at 100 rpm, is 420 MPa·S.

The value of the ROW is of 0.081%.

The phosphate content in this example of the invention in comparison with E. what sperimental No. 13 was completely excluded.

Compared with Experiments No. 12 and No. 13 Experiments No. 14 and No. 15 show that the use of zirconium compounds in combination with polyacrylate according to the present invention provides a stable aqueous dispersion of calcium carbonate in terms of viscosity by Brookfield without the use of phosphate.

Example 5

This example illustrates the use of zirconium compounds in a method of producing a suspension containing calcium carbonate, without the use of phosphate dispersant with the introduction of zirconium compounds directly in the filtered precipitate of calcium carbonate.

In this example, the method according to the present invention is also characterized in that the calcium carbonate in dry form is introduced into the process stage of concentration.

Finally, this example also shows that the method according to the present invention enables a person skilled in the art dispersing calcium carbonate in water in order to obtain a high solids content (more than 70% of the dry weight of mineral matter) and good stability in terms of viscosity by Brookfield.

Experiment No. 16

This experiment illustrates the invention.

Use 450 g of the filtered precipitate of calcium carbonate with a solids content of 65.5 per cent (dry weight of mineral matter)with the following main is granulometries characteristics (as measured with Sedigraph 5100):

- 98% wt. particles have an average diameter of less than 2 μm,

- 77% wt. particles have an average diameter of less than 1 μm,

- 13,7% wt. particles have an average diameter of less than 0.2 microns.

The specified filter cake of calcium carbonate, not containing other chemicals, is dispersed using a 0.60% dry weight of active additive (by dry weight of mineral matter) Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato, and mix. In addition, with stirring, add more than 0.03% of dry weight of active additive (by dry weight of mineral matter) polyacrylate dispersant, manufactured by COATEX under the brand name Coatex GXN.

The resulting slurry is then concentrated using a laboratory evaporator, followed by additional introduction of 0.10% of the dry weight of active additive (by dry weight of mineral matter) Bacote 20, manufactured by MEL CHEMICALS, which is a compound of ammoniacarbonate.

The final solids content is 71.0% (by dry weight of mineral matter), and the suspension is stable viscosity according to Brookfield, equal to 270 MPa·S.

The value of the ROW is 0,009%. This value is significantly lower than that obtained for Experiment No. 13, which illustrates a prototype; the method according to the of the present invention enables a person skilled in the art to significantly reduce the number polycarboxylate dispersant, thus, reducing the value of the ROW.

Experiment No. 17

This experiment illustrates the invention.

Use 967 g of the filtered precipitate of calcium carbonate with a solids content of 65.5 per cent (dry weight of mineral matter)with the following main granulometric characteristics (as measured with Sedigraph 5100):

- 98% wt. particles have an average diameter of less than 2 μm,

- 77% wt. particles have an average diameter of less than 1 μm,

- 13,7% wt. particles have an average diameter of less than 0.2 microns.

The specified filter cake that does not contain other chemicals, oiaut with the introduction of 0.60% of the dry weight of active additive (by dry weight of mineral matter) Bacote 20, manufactured by MEL CHEMICALS, which is a compound of ammoniacarbonate, and mix. In addition, with stirring, add more than 0.03% of dry weight of active additive (by dry weight of mineral matter) polyacrylate dispersant, manufactured by COATEX under the brand name Coatex GXN.

The suspension has a solids content of 65.0% (by dry weight of mineral matter), and then focus with the introduction of the same calcium carbonate in the form of a spray dried powder up until the solids content reaches 71,2%.

After the introduction of 0.60 % of the dry weight of active additive (dry is the mass of mineral matter) Bacote 20 and 0.03% of the dry weight of active additive (by dry weight of mineral matter) Coatex GXN get a stable suspension of calcium carbonate with a viscosity according to Brookfield, equal to 280 MPa·S.

The value of the ROW is 0,009%. This value is significantly lower than that obtained for Experiment No. 13, which illustrates a prototype; the method according to the present invention enables a person skilled in the art to significantly reduce the number polycarboxylate dispersant, thereby reducing the value of the ROW.

Experiment No. 18

This experiment illustrates the invention.

Use 964 g of the filtered precipitate of calcium carbonate with a solids content of 65.5 per cent, with the following main granulometric characteristics (as measured with Sedigraph 5100):

- 98% wt. particles have an average diameter of less than 2 μm,

- 77% wt. particles have an average diameter of less than 1 μm,

- 13,7% wt. particles have an average diameter of less than 0.2 microns.

The specified filter cake that does not contain other chemicals, oiaut with the introduction of a mixture of 0.30% of the dry weight of active additive (by dry weight of mineral matter) Bacote 20, manufactured by MEL CHEMICALS, which is a compound of ammoniacarbonate, and 0.30% of the dry weight of active additive (by dry weight of mineral matter) Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato, and mix. In addition, with stirring, add 0.03% dry wt is s active additives (by dry weight of mineral matter) Coatex GXN.

The suspension has a solids content of 65.5 per cent (on dry weight of mineral matter), and then focus with the introduction of the same calcium carbonate in the form of a spray dried powder and in the presence of 0.03% of the dry weight of active additive (by dry weight of mineral matter) Coatex GXN up until the solids content reaches 71,0%.

The value of the ROW is 0,009%.

After the introduction of the mixture of 0.30% Bacote 20 and 0.3% Zirmel 1000, manufactured by MEL CHEMICALS, which is a compound of salicylaldiminato, and 0.03% of the dry weight of active additive (by dry weight of mineral matter) Coatex GXN entered spray dried powder mineral and adjusting the pH to 10 with a solution of potassium hydroxide gives a stable suspension of calcium carbonate with a viscosity according to Brookfield, equal to 173 mPas

The value of the ROW is of 0.017%. This value is significantly lower than that obtained for Experiment No. 13, which illustrates the prototype of the method according to the present invention enables a person skilled in the art to significantly reduce the number polycarboxylate dispersant, thereby reducing the value of the ROW.

In addition, Experiments No. 16-18 clearly show that the method according to the present invention allows to obtain a stable suspension containing carbonate to Lycia, without the use of phosphate dispersant with the introduction of zirconium compounds directly in the filter cake of calcium carbonate, then concentrating and then introducing calcium carbonate in a dry form.

Example 6

This example shows the use of a suspension containing calcium carbonate containing one or more compounds of zirconium and obtained using the method according to the present invention, in obtaining paints coatings, which are then used for coated paper.

This example also shows the paper according to the present invention, with part of their optical properties, improved when using the suspension containing calcium carbonate containing one or more compounds of zirconium according to the present invention.

In this example, formulations of the compositions of the coating of paper are prepared using different suspensions of calcium carbonate, representing prototype, and the other representing the invention.

The composition of each paint coating has the following composition (in parts by weight of dry products):

The suspension containing calcium carbonate
(calcium carbonate from the firm OMYA):80
the Lina Hydragloss 90
(from HUBER):20
Dispersant Coatex GXN
(from the company COATEX):0,1
Latex binder DOW Latex 966
(from DOW CHEMICALS):11
CMC Finnfix 10
(from company METSA SERLA):0,5
Polyvinyl alcohol Mowiol 6-98
(from the company CLARIANT):0,4
Optical brighteners Blancophor
(from the company CIBA):0,6

Paint coatings are compared after bilateral applying one layer to 58 g/m2base paper, containing wood, when the machine speed 1200 m/min; applied mass of coating comprised 11.0 and 12.5 g/m

Paper handle on the calender Voith Sulzer Supercalender c 11 clamps for linear loads 250 and 270 kN/m and a temperature of 80°C.

In all cases, the opacity is determined according to DIN 5146 using device Elephro 3000.

Experiment No. 19

This experiment illustrates the prototype and uses a suspension of calcium carbonate obtained for Experiment No. 12.

The measured opacity after calendering at 250 kN/m and the cast to 83 g/m2is 88,0%.

The measured opacity after calendering at 270 kN/m and the cast to 83 g/m2is 87,8%.

Experiment No. 20

This experiment illustrates the prototype and uses a suspension of calcium carbonate obtained for Experiment No. 13.

The measured opacity after calendering at 250 kN/m and the cast to 83 g/m2is 88,0%.

The measured opacity after calendering at 270 kN/m and the cast to 83 g/m2is 87,6%.

Experiment No. 21

This experiment illustrates the invention and uses a suspension of calcium carbonate obtained for experiment No. 14.

The measured opacity after calendering at 250 kN/m and the cast to 83 g/m2is 88.2%.

The measured opacity after calendering at 270 kN/m and the cast to 83 g/m2is 88.2%.

The above results show that paper containing aqueous dispersions according to the present invention, shows the opacity equal to slightly improved.

Experiment No. 22

This experience is iment illustrates the invention and uses a suspension of calcium carbonate, obtained for Experiment No. 15.

The measured opacity after calendering at 250 kN/m and the cast to 83 g/m2is 88.3 per cent.

The measured opacity after calendering at 270 kN/m and the cast to 83 g/m2is 87,8%.

The above results show that paper containing aqueous dispersions according to the present invention, shows the opacity equal to slightly improved.

1. A method of obtaining a suspension containing calcium carbonate, characterized in that the suspension containing calcium carbonate, obtained by introducing one or more compounds of zirconium and possibly one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

2. The method according to claim 1, characterized in that it is a grinding method in which:
calcium carbonate in a dry form and/or in the form of an aqueous dispersion, or aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,
or
one or more compounds of the circus is of dry, and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is ground it is possible with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

3. The method according to claim 1, characterized in that it is a way of dispersing, in which:
calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding,
or
one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

4. The method according to claim 1, ex is different, however, it is the way of concentration, in which:
calcium carbonate in a dry form and/or in the form of an aqueous dispersion, and/or in the form of aqueous suspensions or aqueous filter cake is introduced into the aqueous suspension and/or emulsion of water and/or aqueous solution containing one or more compounds of zirconium, and the resulting composition is concentrated possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding, or
one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion and/or an aqueous solution is introduced into the aqueous dispersion or aqueous suspension or aqueous filter cake of calcium carbonate, and the resulting composition is concentrated possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

5. The method according to claim 1, characterized in that it is a way of dispersing, in which:
the calcium carbonate pigment sediment, selected among the precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya, and the specified residue, preferably having a moisture content above 20% by dry weight of mineral matter, water is introduced into suspend the Yu and/or aqueous emulsion, containing one or more compounds of zirconium, and the resulting composition is dispersed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding, or
one or more zirconium compounds in a dry form and/or in the form of aqueous suspensions and/or aqueous emulsion is mixed with the pigment residue selected among the precipitate filtered and/or centrifuged sediment and/or sludge obtained by the method of elektrokontaktnaya, and the specified residue preferably has a moisture content above 20% by dry weight of mineral matter, and the resulting composition is mixed possibly with one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

6. The method according to any one of claims 1 to 5, characterized in that a compound of zirconium is ammunitionsarsenal, or colitiscondition, or mixtures thereof.

7. The method according to any one of claims 1 to 5, characterized in that the compound of zirconium is served in the form of an aqueous solution and/or aqueous suspensions and/or aqueous emulsion containing from 0.01 to 10% by dry weight of zirconium compounds, more preferably from 0.03 to 5% by dry weight of zirconium compounds.

8. The method according to any one of claims 1 to 5, characterized in that the aqueous suspension and/or water disperse is, containing calcium carbonate, obtained after the stage of mechanical and/or thermal concentration after at least one stage of dry and/or wet grinding without the use of dispersant and at low concentration relative to dry matter less than 40% by dry weight, and optionally followed by additional stage of grinding.

9. Aqueous suspensions and/or aqueous dispersion of calcium carbonate, characterized in that they are obtained by the method according to any one of claims 1 to 8.

10. Aqueous suspensions and/or aqueous dispersion of calcium carbonate according to claim 9, characterized in that they contain more than 45% by dry weight of calcium carbonate, preferably more than 65% by dry weight of calcium carbonate, and most preferably more than 78% by dry weight of calcium carbonate.

11. Aqueous suspensions and/or aqueous dispersion of calcium carbonate according to claim 9 or 10, characterized in that they contain one or more compounds of zirconium and possibly one or more other additives that do not contain phosphate acting as a dispersant and/or additive that promotes grinding.

12. Aqueous suspensions and/or aqueous dispersion of calcium carbonate according to any one of p or 10, characterized in that a compound of zirconium is ammunitionsarsenal, or colitiscondition, or mixtures thereof.

13. The method of obtaining dry mineral pigment carb is Nata calcium, different drying aqueous suspensions and/or aqueous dispersions of calcium carbonate according to any one of p-12.

14. Dry mineral pigment calcium carbonate, characterized in that it is obtained by the method according to item 13.

15. The use of aqueous suspensions and/or aqueous dispersions of calcium carbonate according to any one of p-12, and/or dry mineral pigments calcium carbonate in 14 in obtaining paper and/or paper and/or polymer coatings as fillers for plastics or for the compositions of aqueous paints.

16. The product containing aqueous suspensions and/or aqueous dispersion of calcium carbonate according to any one of p-12.

17. Product P16 selected from the group comprising paper, plastics and paints.



 

Same patents:

FIELD: printing industry.

SUBSTANCE: to produce a precipitated calcium carbonate, a suspension of calcium hydroxide is made by mixing of quicklime with water in a reactor with a mixer or in a tank, then the produced suspension is filtered via a 100-mcm filter. The filtered suspension is sent into a reactor of stainless steel equipped with a mixer. Temperature from 10 to 70°C is set, afterwards the suspension is sent into a reactor or a tank for carbonisation, where a carbon-containing gas is bubbled through the suspension. The suspension is drained from the tank, when electric conductivity achieves the minimum level, and pH falls below 8. Coarse particles are removed at a 45-mcm filter. At the same time the carbonisation stage is carried out at speed of carbonising gas flow of below 30 litres per minute under normal conditions per kg of calcium hydroxide in process of deposition. Concentration of precipitated calcium carbonate is increased using a cationic, anionic or combined disperser under quite moderate or mild conditions, which do not cause considerable damage of aggregates/agglomerates, until concentration from 25 to 60% is achieved, preferably in the range from 35 to 50%, most preferably - from 39 to 40 wt % of hard substances.

EFFECT: invention makes it possible to produce porous stable agglomerates of precipitated calcium carbonate with size of 1-5 mcm.

22 cl, 5 dwg, 17 tbl, 9 ex

FIELD: printing industry.

SUBSTANCE: to produce a precipitated calcium carbonate, a suspension of calcium hydroxide is made by mixing of quicklime with water in a reactor with a mixer or in a tank, then the produced suspension is filtered via a 100-mcm filter. The filtered suspension is sent into a reactor of stainless steel equipped with a mixer. Temperature from 10 to 70°C is set, afterwards the suspension is sent into a reactor or a tank for carbonisation, where a carbon-containing gas is bubbled through the suspension. The suspension is drained from the tank, when electric conductivity achieves the minimum level, and pH falls below 8. Coarse particles are removed at a 45-mcm filter. At the same time the carbonisation stage is carried out at speed of carbonising gas flow of below 30 litres per minute under normal conditions per kg of calcium hydroxide in process of deposition. Concentration of precipitated calcium carbonate is increased without using an agent that promotes dispersion or with application of a cationic disperser under quite moderate or mild conditions, which do not cause considerable damage of aggregates/agglomerates, until concentration from 15 to 50% is achieved, preferably in the range from 20 to 30%, most preferably - from 23 to 26 wt % of hard substances.

EFFECT: invention makes it possible to produce porous stable agglomerates of precipitated calcium carbonate.

22 cl, 5 dwg, 9 tbl, 12 ex

FIELD: textile fabrics, paper.

SUBSTANCE: method is related to production of coated paper or cardboard. Method includes application of pigment composition as coating on at least one side of paper or cardboard web. Specified pigment composition is water dispersion, which includes optionally aggregated colloidal particles of silicon dioxide or aluminium silicate as pigment particles, which are prepared from alkali metal silicate by ion exchange or pH reduction and having surface area of approximately from 30 m2/g to approximately 450 m2/g. Coating contains also at least one cationic component selected from group that consists of water-soluble aluminium salts and cationic polymers with molecular weight from approximately 2,000 to approximately 1,000,000 and charge density from approximately 0.2 mEq/g to approximately 12 mEq/g, in which at least approximately 0.4 g of pigment particles from pigment composition is applied on m2 of coated side of paper or cardboard web. Invention is also related to paper or cardboard produced by this method. It is also related to composition of above mentioned pigment in the form of water dispersion, which includes less than approximately 3 wt % of organic binders and to method of above mentioned pigment composition production, in which mixing is done to produce water dispersion in order to avoid gel formation and deposition.

EFFECT: improvement of printing and strength properties of coating, and also lower scuffing of paper.

26 cl, 5 tbl, 4 ex

FIELD: textiles; paper.

SUBSTANCE: composition is designed for refining fibrous material, can be used in the production of enamelled cardboard and paper and relates to the cellulose-paper industry. The composition contains a modified pigment and a water soluble binding substance. The pigment is calcium sulfoaluminate, modified starch or polyvinyl alcohol with mass ratio content of 0.5-1.5. The water soluble binding substance is starch.

EFFECT: resistance to fluffing and whiteness of the coating with considerable lowering of consumption of the binding substance when making the composition.

1 tbl

FIELD: textiles, paper.

SUBSTANCE: solution is meant for rifining of fibrous material. It pertains to the field of paper manufacturing and cardboard during manufacturing of chalk-overlay types of cardboard and paper. The solution consists of water soluble binder. A mixture of calcium salfoaluminate and kaolin, modified starch or polyvinyl spirit is used as the pigment. The technical result is high stability to picking, whiteness, colour perception and smoothness. The solution enhances adhesion of the coating to the base (cardboard or paper), which makes it possible to use the refined coating as a sub-layer when dual or tri-coating cardboard or paper, with obtaining products with a given range of characteristics.

EFFECT: obtaining of a solution for refining material for production of paper and cardboard during production of chalk-overlay types of cardboard and paper.

1 tbl, 1 exr

FIELD: light industry; composition of decorative coats for wallpaper; manufacture of pearly ink for intaglio printing on wallpaper.

SUBSTANCE: composition of proposed printing ink for wallpaper contains 16-16.5 mass-% of pearly pigment; 12-12.5 mass-% of ethyl alcohol; 46-46.4 mass-% of binder - acrylic latex of butyl acrylate copolymer (19-21%) and methacrylic acid (10-12%) and water; copolymer acrylic latex is produced by method of radiation emulsion polymerization of butyl acrylate, vinyl acetate and methacrylic acid under action of ionizing radiation at dose rate of 0.05-0.1 g/s to absorbed doses of 1.5-2 kgr.

EFFECT: avoidance of lamination of ink; easily washable ink; enhanced heat resistance of ink.

1 tbl, 2 ex

FIELD: chemical industry; printing industry; powder metallurgy industry; cosmetic industry; other industries; production and application of the highly anticorrosive metallic pigments.

SUBSTANCE: the invention is pertaining to production of the of the highly anticorrosive metallic pigments similar to laminas, which may be used in production of the printing ink, plastic materials, cosmetics, the powder coatings and in other branches of industry. The pigments have on their surfaces: the metallic substrates similar to the laminas and treated with the compounds of the phosphoric acid and-or the compounds of the boric acid; one or more layers of the coatings consisting of one or more hydrated oxides of the metals of one or more metals selected from the group, which includes silicon, aluminum, zirconium, titanium and tin. On the basis of the highly corrosive metallic pigments similar to laminas it is possible to produce the interferential colored pigments. The invention allows to increase the anticorrosive resistance of the metallic pigments at the expense of saving without the faults of the initial surface smoothness of the similar to the laminas metallic substrates, to increase the homogeneity and density of the layers of the hydrated oxides of the metals.

EFFECT: the invention ensures the increased anticorrosive resistance of the metallic pigments, saving the initial surface smoothness of the similar to the laminas metallic substrates, the increased homogeneity and density of the layers of the hydrated metals oxides.

40 cl, 9 ex, 4 tbl, 8 dwg

FIELD: pulp-and-paper industry, in particular, paper sheet having surface feeling hash to the finger, and method for applying coating onto paper sheet.

SUBSTANCE: paper sheet of such structure may be used for manufacture of paper or plastic medium for carrying of printed information, paper or plastic package, cover used in stitching and binding processes, or cardboard or plastic carton having surface feeling hash to the finger. At least one side of paper sheet is coated with layer containing non-compressible microscopic particles of non-gelatinized starch grains, or said particles are produced by grinding of plastic material. Method involves treating at least one side of paper sheet with water-based composition containing non-compressible microscopic particles which are made three-dimensional and rounded, binder, and filler; drying paper sheet after treatment. Particles are non-gelatinized starch grains, or particles are produced by grinding of plastic material. Method allows paper sheet to be produced, which has roughness coefficient Kd below 0.5.

EFFECT: simplified method and improved quality of paper sheet.

17 cl, 16 dwg, 1 tbl, 3 ex

FIELD: chemical industry; printing industry; other industries; methods of production of the composition of the paint including the optically changeable pigments.

SUBSTANCE: the invention may be used in production of the optically changeable pigments. The optically changeable pigment includes the stratified set composed of the different materials, in which, at least, one of the layers represents the reflecting layer and, at least, one of the other layers represents the dielectric layer. At least, one of the surfaces of the indicated layers is subjected to the chemical action. The indicated materials also include, at least, one of the layers, which represents the semitransparent metallic layer made out of chromium and also one or more metals and-or their inorganic compounds. At that the metal and-or its inorganic compound are subject to corrosion. The subjected to the chemical action surface of the reflecting and dielectric layer along the edge of the layering block of the edge structure of the pigment is coated with the passivating agent, which is selected from the group consisting of the organic esters and the fluorinated organic esters of the phosphoric acid, having the following structural formula: (Rf-CH2-CH2-O)xP(O)(OH)y, where Rf=F-(CF2-CF2)z, х=1 or 2, у=2 or 1, х+у=3, z=l-7. The composition of the printing paint includes the binding system, water and the optically changeable pigment. The invention allows to diminish oxidation of the metallic layers and dissolution of the dielectric layers of the optically changeable pigment and to use it in the compositions of the printing paint.

EFFECT: the invention allows to diminish oxidation of the metallic layers and dissolution of the dielectric layers of the optically changeable pigment and to use it in the compositions of the printing paint.

22 cl, 7 ex

FIELD: production of ink-jet printing paper with special pigment coat applied thereto.

SUBSTANCE: method involves manufacturing paper-base; applying onto one side of paper-base ink-perceptive coat consisting of pigment, binder and cationic fixative; applying onto opposite side of paper-base curling-preventive coat; refining both surfaces of paper; using mixture of amorphous silicon dioxide and calcium or kaolin carbonate as ink perceptive pigment for coat, said mixture having specific outer surface less than 20 m2/g in the ratio of (75-45):(25-55); using polyvinyl alcohol as binder in an amount of 20-25% by weight of pigment; using polydiallyl dimethylammonium chloride as cationic fixative.

EFFECT: improved printing characteristics and increased paper surface strength.

3 cl, 1 tbl, 7 ex

FIELD: printing industry.

SUBSTANCE: to produce a precipitated calcium carbonate, a suspension of calcium hydroxide is made by mixing of quicklime with water in a reactor with a mixer or in a tank, then the produced suspension is filtered via a 100-mcm filter. The filtered suspension is sent into a reactor of stainless steel equipped with a mixer. Temperature from 10 to 70°C is set, afterwards the suspension is sent into a reactor or a tank for carbonisation, where a carbon-containing gas is bubbled through the suspension. The suspension is drained from the tank, when electric conductivity achieves the minimum level, and pH falls below 8. Coarse particles are removed at a 45-mcm filter. At the same time the carbonisation stage is carried out at speed of carbonising gas flow of below 30 litres per minute under normal conditions per kg of calcium hydroxide in process of deposition. Concentration of precipitated calcium carbonate is increased using a cationic, anionic or combined disperser under quite moderate or mild conditions, which do not cause considerable damage of aggregates/agglomerates, until concentration from 25 to 60% is achieved, preferably in the range from 35 to 50%, most preferably - from 39 to 40 wt % of hard substances.

EFFECT: invention makes it possible to produce porous stable agglomerates of precipitated calcium carbonate with size of 1-5 mcm.

22 cl, 5 dwg, 17 tbl, 9 ex

FIELD: printing industry.

SUBSTANCE: to produce a precipitated calcium carbonate, a suspension of calcium hydroxide is made by mixing of quicklime with water in a reactor with a mixer or in a tank, then the produced suspension is filtered via a 100-mcm filter. The filtered suspension is sent into a reactor of stainless steel equipped with a mixer. Temperature from 10 to 70°C is set, afterwards the suspension is sent into a reactor or a tank for carbonisation, where a carbon-containing gas is bubbled through the suspension. The suspension is drained from the tank, when electric conductivity achieves the minimum level, and pH falls below 8. Coarse particles are removed at a 45-mcm filter. At the same time the carbonisation stage is carried out at speed of carbonising gas flow of below 30 litres per minute under normal conditions per kg of calcium hydroxide in process of deposition. Concentration of precipitated calcium carbonate is increased without using an agent that promotes dispersion or with application of a cationic disperser under quite moderate or mild conditions, which do not cause considerable damage of aggregates/agglomerates, until concentration from 15 to 50% is achieved, preferably in the range from 20 to 30%, most preferably - from 23 to 26 wt % of hard substances.

EFFECT: invention makes it possible to produce porous stable agglomerates of precipitated calcium carbonate.

22 cl, 5 dwg, 9 tbl, 12 ex

FIELD: textile, paper.

SUBSTANCE: method includes provision of a thick mixture of cellulose suspension, which contains a filler. The thick suspension mass is dissolved to form a diluted mix of suspension, in which the filler is available in amount of at least 10 wt % in terms of dry mass of dissolved suspension mix. The thick mixture of suspension and/or dissolved mix are flocculated. Polymer system of retention/dehydration is used in flocculation. The dissolved mixture of suspension is dehydrated on a mesh to form a sheet, and then the sheet is dried. In this method the polymer system of retention/dehydration contains the following: i) a water-soluble branched anion-active polymer and ii) a water-soluble cation-active or amphoteric polymer. The anion-active polymer is available in the thick mixture or in the dissolved mixture of suspension prior to addition of cation-active or amphoteric polymer.

EFFECT: improved retention of ash relative to complete retention with higher quality of paper.

16 cl, 21 dwg, 32 tbl, 8 ex

FIELD: textile, paper.

SUBSTANCE: method includes provision of a thick mixture of suspension, which contains wood mass and a filler. The thick suspension mix is dissolved to form a diluted mix of suspension, in which the filler is available in amount of at least 10 wt % in terms of dry mass of dissolved suspension mix. The thick mix and/or dissolved mix of the suspension are flocculated, using a polymer system of retention/dehydration. The dissolved mixture of suspension is dehydrated on a sieve to form a sheet, and then the sheet is dried. The polymer system of retention/dehydration contains the following: i) a water-soluble branched anion-active polymer and ii) a water-soluble cation-active or amphoteric polymer. The method may be realised on paper-making machines of quick dehydration, such as GAP former.

EFFECT: improved retention of ash with reduction of dehydration.

16 cl, 26 dwg, 46 tbl, 16 ex

FIELD: textile, paper.

SUBSTANCE: paper base is designed to form a decorative material of a coating. It represents a non-processed paper containing a white pigment and/or fillers and is coated with a covering solution, containing at least one water-soluble modified starch with special distribution of molecules according to molecular weight. Also a decorative paper or decorative material is proposed to form coatings with application of the above-specified paper-base.

EFFECT: improved quality of a finished product due to increased inner strength of fixation with high non-transparency and other mechanical properties, improved stability of paper size stability and increased average size of its pores.

7 cl, 2 tbl, 6 ex

FIELD: textile, paper.

SUBSTANCE: method of filler treatment includes formation of a mixture of an aqueous suspension of filler and aqueous anion latex. The latter is a dispersion of acrylic polymer with vitrification temperature (T v) from - 3 to 50°C. This mix is mixed with water at the temperature that is higher than T v of latex, at the same time the specified water has temperature of 40-98°C. The specified suspension of the filler comprises a solid disperse filler selected from the group containing kaolin clay, ground calcium carbonate, deposited calcium carbonate, deposited calcium sulfate, talc and mix of two or more of them. The specified acrylic polymer is selected from the group containing copolymers n-butylacrylate-acrylonitrile-sterol and copolymers n-butylacrylate-sterol. The aqueous composition of the filler contains the solid dispersed filler specified above with solid particles of anion latex polymer specified above and adsorbed on them, in aqueous carrier. The treated filler contains the solid dispersed filler specified above with solid particles of anion latex polymer specified above and adsorbed on them. The pulp charge contains pulp fibres and the solid dispersed filler specified above with solid particles of anion latex polymer specified above and adsorbed on it, in aqueous carrier. Method to make paper from the above specified pulp charge containing pulp fibres. The paper product made of pulp fibres and solid disperse filler, where the specified filler has solid particles of anion latex polymer specified above absorbed on it, with size of solid polymer particles of 30-200 nm and in amount of 1-100 kg of latex per 1 t of filler relative to dry mass of solid substances of latex and filler, and the specified filler has average size of particles of 0.1-30 mcm.

EFFECT: improved retention of the filler, continuous execution of the filler treatment method to improve fixation of anion latex on the filler for a short period of time due to irreversible fixation of anion latexes on particles of the filler and time stability of aggregated filler suspension, latex-treated deposited calcium carbonate is more acid-resistant, and when used to make paper from wood mass under neutral conditions less acid is required to control pH.

21 cl, 14 dwg, 8 ex

FIELD: textile, paper.

SUBSTANCE: method includes dissolution of cellulose and its grinding down to specified extent of grinding. Preparation of the first dispersion with application of return water, containing fibres of microcrystal cellulose, produced by its grinding in mixture with titanium dioxide and calcium hydroxide in specified amount. The second dispersion is prepared from cellulose fibres with application of return water. Then the first suspension is mixed with the second, and produced mixture is treated with carbon dioxide. In case of this treatment calcium hydroxide under action of carbon dioxide results in production of chemically deposited chalk and production of paper mass at specified ratio of components. Grinding of microcrystalline cellulose in mixture with titanium dioxide and calcium hydroxide is carried out in vibration mill with provision of impact and wear effect at mixture.

EFFECT: increased extent of fillers retention in paper, improvement of its printing properties, provision of possibility to vary bulk and porosity of paper, provision of possibility to use fully closed cycle of return water.

1 tbl, 8 ex

FIELD: textile, paper.

SUBSTANCE: method includes preparation of water dispersion of cellulose fibres. Addition of calcium hydroxide in it at specified ratio in dispersion of cellulose fibres. Further treatment of dispersion with carbon dioxide in process of mixing until calcium hydroxide is fully transformed into calcium carbonate to produce paper mass. The latter comprises cellulose fibres, modified with chemically deposited chalk. At the same time calcium hydroxide is added into dispersion in amount, in conversion to calcium carbonate, equal to its specified percentage content in dry substances of paper. Dispersion of cellulose fibres is prepared with addition of return water of paper-making machine, and dispersion is treated with carbon dioxide after addition of return water to it. Paper mass is produced with specified content of components in it without account of solid substances added in it with return water. Cellulose fibre is selected from row including sulfite, sulfate cellulose, their mixture, leached wood mass of high yield on the basis of fibrillated fibres containing cellulose, hemicellulose and lignin.

EFFECT: increased strength of paper from produced paper mass due to use of closed cycle of water circulation.

1 tbl

FIELD: chemistry.

SUBSTANCE: substrate has a paper base containing cellulose fibre from deciduous wood with particle size smaller than 200 mcm after grinding in amount of not more than 45 wt % and average fibre length between 0.4 and 0.8 mm and filler in amount of 5-40 wt %, particularly 10-25 wt % in terms of the weight of cellulose.The substrate at least contains one polymer layer lying at least on one side of the paper base. There is a layer with a binding agent between the polymer layer and the paper base. The binding agent is a hydrophilic film-forming polymer made from hydroxypropylated starch and/or thermally modified starch. This layer may contain a pigment in form of calcium carbonate, kaolin, talc, titanium dioxide and/or barium sulphate.

EFFECT: reduced limpness and obtaining pure-bred production wastes.

27 cl, 3 tbl

FIELD: paper.

SUBSTANCE: paper base contains fibers of coniferous and deciduous wood, or their mixtures, which have average length that is more or equal to 75 mcm and have filler fixed to part of these fibers, and also less than 50 wt % of fibers have average length less than 75 mcm from total weight of base. Paper mass is produced by contact of deciduous or coniferous wood fibers or their mixtures having average length of 75 mcm and having filler fixed to part of mentioned fibers, with fibers average length of which is less than 75 mcm, from total weight of base.

EFFECT: improved smoothness of paper.

20 cl, 25 dwg, 3 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: described is a method of producing composite pigment material based on composite particles of a pigment of titanium dioxide and calcium carbonate in micro-marble form. The method involves separate preparation of aqueous dispersions of said components in a high-speed dissolver for 20 minutes, followed by mixing the two dispersions. Titanium dioxide is dispersed in the presence of a polymer dispersant based on an AB-block-copolymer, and the micro-marble is dispersed in the presence of sodium tripolyphosphate. The obtained mixture of the composite pigment material is ready for adding into paint.

EFFECT: simple technique of obtaining pigment material based on titanium dioxide while preserving its physical and chemical properties which correspond to standards, reduction of the amount of expensive titanium dioxide in paints.

1 tbl, 3 ex

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