Paper for spray printing containing polyvinyl alcohol with amine functional groups

FIELD: process of production of paper having a specific coating, applicable for spray printing.

SUBSTANCE: a coating composed of polyvinyl alcohol with primary amine functional groups and mineral pigment is applied onto the paper surface.

EFFECT: improved quality of paper for spray printing.

21 cl, 13 dwg, 3 tbl, 11 ex

 

The technical field

The invention relates to paper with a special coating that makes it very suitable for use with inkjet printers.

The LEVEL of TECHNOLOGY

The success inkjet print technology pose new requirements for paper for printing and coating of paper. To ensure proper quality printed sublayer must quickly absorb ink and media ink immediately after printing, to provide a maximum optical density of the ink, to ensure a minimum flow and capillary wicking of the ink and to provide a means of giving water to the paint.

Typically, coatings for inkjet printing containing silica pigment having a high absorption capacity, and a polymer binder, such as adhesion to poly(vinyl alcohol)having a high cohesive strength. To improve the coating properties are a variety of supplements. For example, cationic additives introduced to increase the water resistance and light fastness of the dye. Other changes in coating compositions for ink jet printing include decrementally pigments, such as clay, aluminum hydrate, calcium carbonate, titanium dioxide, magnesium carbonate; and also apply a binder such as a copolymer of butadiene and styrene, poly(vinyl pyrrolidone), polyvinylene is at, acrylic binder and starch.

Referred to the following patents and articles are a variety of resins and coatings paper for inkjet printing.

U.S. patent No. 4818341 describes the introduction of a cationic polymer, for example, hydrolyzed vinyl acetate or copolymers of finalproject/N-vinylformamide, a lot of paper to increase the strength in dry condition all types of paper and cardboard, such as writing paper and wrapping paper. The polymer is injected in an amount of from 35 to 150 g/sqm paper and up to 600 g/sq.m for cardboard.

U.S. patent No. 4880497 describes the introduction of the water-soluble copolymers containing polymerized units of vinylamine, for example, hydrolyzed copolymer of vinyl acetate/N-vinylformamide in a lot of paper before the formation of the sheets in the amount of from 0.1 to 5% by weight of dry fiber.

Lined patent application of Japan in the name Kokai No. 5-278323 describes a sheet for recording information having good absorption properties of the paint, giving a good image and has good water resistance; and containing layer, fixing the dye on which is laminated a layer for adsorption of the dye. One of the main components of the dye fixing layer placed on the sheet for recording information is nationaldirectory polyvinyl alcohol.

Nationaldirectory polyvinyl alcohols are characterized as italiaanse copolymers of vinyl acetate and etileno-unsaturated monomers, having Quaternary groups ammonium salts. The content of cationic groups is from 0.1 to 10 molar percent.

Summary of the application of Japan No. A describes the acceptor image used for recording information by means of inkjet printing. The acceptor image contains silica pre-treated water-soluble resin or on the surface of the recording information, or in the acceptor. The sodium silicate solution and sulfuric acid is mixed with 5% kationmodifitsirovannogo polyvinyl alcohol and put on a sheet of paper, and then paint is applied to the sheet.

The Japan patent No. 05139023 describes a coating for inkjet printing water-based, containing silica pigment and a fully hydrolyzed, having an average molecular weight of poly(vinyl) alcohol. This was coated on a paper base in a weight amount of 0.7-0.8 g/s / C to ensure high-quality color images with good form pixels.

German patent No. 514633 A1 921125 describes a coating for inkjet printing containing 50% silica pigment, 40% poly(vinyl alcohol) with a value of hydrolysis of 92.5% and 10% cationic polyacrylamide. When applied to a paper base coating in an amount of 10 g/sq.m this coating provides good optical density of the color image and a small diameter dots that provides good doscover is here printed image.

The Japan patent No. 01186372 A2 890725 describes the polyacrylamide additive in the coating for inkjet printing containing silica pigment and a fully hydrolyzed, low molecular weight poly(vinyl) alcohol. This coating provides good resistance to smudge, and light resistance.

The Japan patent No. 06247036 A2 940906 discloses the use of cationic polyethylenimine Quaternary ammonium salts in combination with silica pigment and a fully hydrolyzed, low molecular weight poly(vinyl) alcohol as a layer, perceiving spray paint.

The Japan patent No. 61134291 A2 860621 describes cationic PVON-binder for use in the coating for inkjet printing; as a binder is used saponified copolymer trimethyl-3-(1-acrylamidoethyl)ammonium chloride/vinyl acetate, with the percentage of hydrolysis of 98.5 and cation content of 3 mol.%, and with a degree of polymerization of 1750. Coverage using this binder with silica pigment, provide a good reliability of the printed image and good resistance to paper.

U.S. patent No. 5405678 describes the inkjet paper with a basis covered coagulating latex film containing a hydrophobic polymer, for example, copolymers of ethylene/vinyl chloride, acrylic latexes, silica and the dispersant.

P is the awning U.S. No. 5270103 describes perceiving paint the leaves, made with printed on them such water-based paint that is used in inkjet printing systems. In the coating composition includes a pigment and a binder consisting of polyvinyl alcohol and a polymer, which, for example, may be cationic polyvinyl alcohol and poly(vinyl pyrrolidone).

U.S. patent No. 6096826 describes the synthesis of polyvinyl alcohol with aminovymi functional groups due to the reaction of piperidine with particles of poly(vinyl alcohol). The final product is suitable as mordant agent/binder for coated paper for inkjet printing.

U.S. patent No. 6096440 describes the use of the recording media information inkjet printing with perceiving the paint layer consisting of a hydrophilic resin, blockcopolymer polyvinyl alcohol and a hydrophobic polymer. This patent also describes the use kationmodifitsirovannogo poly(vinyl alcohol) "Kurray CM-318", manufactured by Kuraray Co. Ltd, as a binding layer for receiving ink jet printing.

The INVENTION

The present invention relates to improvements in the paper, having a coating for inkjet printing, water-based, applied to the surface of the paper. The improvement is mainly in the introduction of polyvinyl alcohol with functional groups of the primary amine (PVOH/NH2in the when asked polymeric binder in the coating for inkjet printing. One form of polyvinyl alcohol with aminovymi functional groups produced by hydrolysis of a copolymer of vinyl acetate and N-vinylformamide (PVOH/PVNH2); the other form is produced by polymerization of vinyl acetate and allylamine; another form is a 4-aminobutyrate derivative of polyvinyl alcohol.

Paper containing an improved coating for inkjet printing, has several advantages. These advantages are: the presence of polyvinyl alcohol with a primary aminovymi functional groups as a polymeric binder in the coating for inkjet printing facilitates the preparation of the coating composition by eliminating the need for the introduction of cationic materials;

the introduction of polyvinyl alcohol with a primary aminovymi functional groups provides a good bonding strength due to the siliceous pigments used in coatings for inkjet printing;

the introduction of polyvinyl alcohol with a primary aminovymi functional groups provides a good optical density of the ink for monochrome black composite black and primary colors;

the introduction of polyvinyl alcohol with a primary aminovymi functional groups provides good water resistance of the printed ink;

the introduction of polyvinyl alcohol with a primary and Inouye functional groups provides good resistance to light paint;

the introduction of polyvinyl alcohol with a primary aminovymi functional groups provides good rheological characteristics from the point of view of the shear thickening when used in conjunction with silica pigment, making the content of solids in the coating of paper can be increased, which in turn can provide the possibility of increasing the weight of the coating and increase the speed of production; and

the introduction of polyvinyl alcohol with a primary aminovymi functional groups provides good drying time of the ink after printing on the coated paper for inkjet printing.

Usually polyvinyl alcohol with a primary aminovymi functional groups selected from the group consisting of hydrolyzed copolymers of vinyl acetate and N-vinylamide, hydrolyzed copolymer of vinyl acetate and allylamine, and primary aminoalkylated derivatives of polyvinyl alcohol.

LIST of FIGURES

The invention is explained in detail below in conjunction with the drawings, in which:

Figure 1 is a histogram illustrating the optical density ink-jet ink monochrome black depending on the resin used and the amount of mineral filler;

Figure 2 is a histogram illustrating the optical density of the composite black depending on the resin and the amount of mineral filler;

Figure 3 is a histogram illustrating the optical density of Magenta depending on the level of the filler and the resin used;

4 is a histogram illustrating the optical density of the yellow depending on the resin and silica;

5 is a histogram illustrating the optical density of blue depending on the resin used and the level of silica filler;

6 is a graph of the dependence of viscosity on shear factors for different formulations of coatings for inkjet printing;

7 is a histogram illustrating the drying time of paint on different coatings based on silica/poly(vinyl alcohol);

Fig - histogram illustrating the optical density of the monochrome black and composite black for different leaf-bases coated and uncoated;

Figure 9 is a histogram illustrating the resistance monochrome black ink on the paper surface sizing and coating of various resins;

Figure 10 is a histogram illustrating the tensile strength in the dry state paper surface sizing in comparison with the coated paper;

11 is a histogram illustrating the optical density of the monochrome black and composite black for different coated paper;

Fig - histogram illustrating the resistance of cu is ski monochrome black sheets bases coated and uncoated; and

Fig - histogram illustrating the optical density of the monochrome black and composite black for different paper coated and uncoated.

DETAILED description of the INVENTION

The invention relates to improvements in the manufacture of paper, preferably used for inkjet printers. Obtaining an improved inkjet papers mainly lies in the fact that the coating for inkjet printing is applied on the surface of the paper. In particular, the improvement is the introduction of a polymer of polyvinyl alcohol with aminovymi functional groups as a binder for coatings for inkjet printing.

Polyvinyl alcohols with aminovymi functional groups are known, examples of such alcohols described in U.S. patent No. 5380403, Robeson et al., included in this document as a reference. For clarification and more detailed presentation of the main decisions of the patent '403 it should be noted that the methods of preparation of poly(vinyl alcohols) with aminovymi functional groups include: the copolymerization of vinyl acetate with N-vinylamides, for example, N-vinylformamide or N-vinylacetate; or copolymerization with allylamine, followed by hydrolysis; or the polymerization of vinyl acetate followed by hydrolysis, to form a derivative of polyvinyl Speer is a, and subsequent reaction with 4-aminobutyraldehyde. You can use other methods of obtaining the same or similar types of polyvinyl alcohols with aminovymi functional groups.

The synthesis of the precursor copolymer of vinyl acetate is possible to conduct polymerization in solution, suspension or emulsion. Rodriguez, "Principles of Polymer Systems", p. 98-101, 403, 405 (McGraw-Hill, NY, 1970) describes the polymerization in the bulk and in solution and detailed in emulsion polymerization. For example, in the preparation of poly(vinyl acetate) suspension polymerization of the monomer is usually dispersed in water containing such suspendisse agent as poly(vinyl alcohol), and then injected initiator such as a peroxide. Unreacted monomer is removed and the polymer is filtered and dried. The preferred method involves the polymerization of vinyl acetate and N-vinylformamide in methanol, which gives a "paste-like" products, which easily undergoes hydrolysis.

A variety of comonomers, for example ethylene-unsaturated monomers can be copolymerized with vinyl acetate and/or vinyl acetate and N-vinylformamide, or allylamino, to obtain a copolymer based on polyvinyl alcohols with aminovymi functional groups. Representatives, but not only them, ethylene-unsaturated monomers are1With 8-esters of acrylic acid and methacrylic acid, unsaturated carboxylic acid and hydrocarbon monomers. Examples of esters include methyl methacrylate, acrylate, butyl acrylate and 2-ethyl hexyl acrylate. Other examples are such hydrocyclone esters, as hydroxyethylacrylate. The monomers are usually used at levels of about 10 mol.% and preferably approximately less than 5 wt.%.

The preferred copolymer for use as a binder in coating compositions for ink jet printing is basically a copolymer of vinyl acetate and N-vinylformamide containing from about 70 to 99 mol.% vinyl acetate and from about 1 to 30 mol.% N-vinylformamide.

Use the normal reaction temperature to obtain copolymers of vinyl acetate, N-vinylformamide and allylamine. The reaction temperature can be adjusted by the rate of introduction of catalyst and the rate of heat loss. As a rule, it is advisable to maintain an approximate temperature of from 50 to 70aboutAnd to prevent the temperature of approximately more than 80°C. Although it is possible to use such a low temperature as 0°but more economical to the lower temperature limit was about 40°C.

The reaction time will also vary depending on other variables, such as temperature, catalyst, and the right is the degree of polymerization. Generally, it is desirable to continue the reaction until the unreacted remain approximately less than 0.5% N-vinylformamide, allylamine or, if used, of vinyl acetate. Under these conditions, the reaction time is about 6 hours was in General sufficient to complete polymerization, but, if necessary, and the reaction was carried out for approximately 3 to 10 hours, and duration of the reaction may also be others.

The hydrolysis of copolymers of vinyl acetate in accordance with this invention can be performed using methods normally used for poly(vinyl alcohol). To obtain poly(vinyl alcohols) with aminovymi functional groups according to this invention can carry out the hydrolysis of any acid or base, or a combination of both. Hydrolysis is often carried out in several stages: the first stage involves contacting a catalytic amount of base (such as KOH, NaOH), resulting in the hydrolysis of acetate groups. Hydrolysis vinylamine groups can perform at higher levels of authority or by introducing acid with subsequent appropriate time/temperature exposure, to provide the desired level of hydrolysis. In the case of acid hydrolysis: protonium the amino group, to obtain a positive charge, n is straitway anionic group (for example, Cl-, Br-, HSO4-H2PO4-and so on). As amine (-NH2), and protonated options (NH3+X-can be used in this invention. Acids suitable for hydrolysis include mineral acids such as hydrochloric, sulfuric, nitric, phosphoric acid and other commonly used mineral acids, and organic acids such as para-toluene acid, methanesulfonate acid, oxalic acid, etc. Can be used sour salt, consisting of weak bases and strong acids, such as ammonium bisulfate, bisulfite of alkylamine, such as tetrabutylammonium bisulfate. In more detail, the hydrolysis of poly(vinyl alcohol) and copolymers described in "Poly(vinyl alcohol): Properties and Applications", ed. by C.A. Finch, John Wiley & Sons, New York, 1973, p. 91-120 and Poly(vinyl alcohol) Fibers", ed. by I. Sokuruda, Marcel Dekker, Inc., New York, 1985, p. 57-68. Latest review on poly(vinyl alcohol), shown in F.L. Marten, Encyclopedia of Polymer Science and Engineering, 2nded., Vol. 17, p. 167, John Wiley & Sons, New York, 1989. Both documents are included as references.

Another possible way to obtain a poly(vinyl alcohols) with aminovymi functional groups for use in the preparation of coatings for inkjet printing, as described above, involves the reaction of certain blocking is different acylaminoalkyl with polyvinyl alcohol or copolymers of polyvinyl alcohol to polyvinyl alcohols with aminovymi functional groups. Blocked ancillarity include 4-aminobutyraldehyde and other allylacetate (C1-4), which react with the polyvinyl obtaining 4-aminoalkyl polyvinyl alcohol, for example, 4-aminobutyryl polyvinyl alcohol.

The inclusion of a primary amine functionality in polyvinyl alcohol with aminovymi functional groups, for example, hydrolyzed vinyl acetate/N-vinylformamide or hydrolyzed copolymers of vinyl acetate/allylamine, or polymers of polyvinyl alcohol/aminobutyrate is quantitatively the range from about 1 to 30, preferably from about 5 to 20 mol.%. The desired level of conversion of vinyl acetate to vinyl alcohol is approximately equal to from 75 to 100%, preferably from about 80 to 99% hydrolysis, and the level conversion vinylamide in vinylamine is approximately 25 to complete gidrolizovannogo, for example, about 100%. In some preferred embodiments, the implementation of hydrolyzed vinyl acetate is present in amount of from about 80 to 95 mol.%.

Below are the workers and the preferred ranges of use of polyvinyl alcohol with aminovymi functional groups. Assumes that the specified values are "approximate" or an approximate value ranges.

Working and preferred ranges of composition:

Polyvinyl alcohol with a primary aminovymi functional groups
Operating rangeThe preferred range
Molecular weight (average)10000-1700008000-110000
The primary amine content1-30 mol.%5-20 mol.%
Hydrolysis of the acetate80-99%98-99%
Weight. % binder in the coating for inkjet printers10-100%20-60%
The PH of the coating3-104-7

The coating compositions for ink jet printing typically contain silica pigment and possibly small amounts of other mineral pigment. Usually mineral pigment is silica, and it is contained in the coating composition for inkjet printing in approximate quantities from 1 to 90%, preferably from about 30 to 85 wt.%. The level of binder (the basis of solid matters) change within normal levels, or from about 20 to 80 wt.% composition for inkjet printing. The levels of pigment and binder greatly depend on the type of matter covering, used in the preparation of the paper for inkjet printing. SinTe the practical silicates of aluminum with a surface area of about 100 square meters/g, and also clay, talc, calcium carbonate, magnesium silicate, etc. have been and can be used as fillers in coating compositions for ink jet printing. The preferred filler for the coating compositions for ink jet printing is silica having an approximate surface area of from 50 to 700 sq.m/year Composition for inkjet printing may also contain such additives as protivovspenivayushchie substances, surfactants, dyes, ultraviolet absorbers of radiation, the pigment dispersant, a mold inhibitors, thickeners, and substances that increase the resistance.

Composition for ink jet printing is usually applied to the surface of the paper in an amount of from about 2 to 20 g/sqm of coating Weight to some extent depends on the type of coating applicator. Coating for inkjet printing containing polyvinyl alcohol with aminovymi functional groups, applied to the surface of the paper, and not a lot of paper before the formation of the sheets.

Without reference to any specific theory it is believed that the amino group in the polymer with aminovymi functional groups provides a cationic charge on the surface of the paper, which reacts with the anionic groups of the sulfonic direct or acid dye ink jet printing, with the formation of insoluble salts. Forming nerest the action salt, the paint becomes water stable on the paper surface, and the light resistance is improved in the paper products, which contains polyvinyl alcohol with aminovymi functional groups, compared with coatings for inkjet printing containing a homopolymer of poly(vinyl alcohol) as a binder. The binding strength of the pigment and, in particular, the binding strength of the silica pigment is increased if you use coatings for inkjet printing containing polymers poly(vinyl alcohol) with aminovymi functional groups compared to coatings for inkjet printing containing a homopolymer of poly(vinyl alcohol) due to the strong absorption of amines silanolate groups in the silica pigment.

The following examples are given to illustrate obtain the corresponding polyvinyl alcohols with aminovymi functional groups and for illustration of cover systems for inkjet printing to paper.

EXAMPLE 1

Method for producing polyvinyl alcohols with primary aminovymi functional groups

The copolymer poly(vinyl alcohol/vinylamine), denoted here as PVOH/PVNH2(vinylamine - 6 mol.%), receive a first polymerization of a copolymer of vinyl acetate/N-vinylformamide (molar concentration - 94/6) in methanol by radical polymerization. The copolymer of the vinyl acetate is/N-vinylformamide hydrolyzing to the copolymer of vinyl alcohol/N-vinylformamide by alkaline saponification of vinyl acetate using a 0.1-molar sodium methoxide in methanol. Copolymer of vinyl alcohol/N-vinylformamide hydrolyzing to the copolymer of vinyl alcohol/vinylamine-HCl by heating at 90°C for 6 hours in distilled water, to which add HCl. The product is precipitated with methanol and then dried in a vacuum oven. The average molecular weight of the PVOH copolymer/PVNH2is approximately 95,000 (Mw), the percentage of hydrolysis of the acetate is 100% and the percentage of hydrolysis of N-vinylformamide - 100%.

The second copolymer (PVOH/PVNH2)poly(vinyl alcohol/vinylamine) (12 mol.% vinylamine) receive a first polymerization of a copolymer of vinyl acetate/N-vinylformamide (molar concentration - 88/12) in methanol by radical polymerization. The molecular weight of the PVOH copolymer/PVNH2equal 96000, the percentage of hydrolysis of the acetate is 100%, and the percentage of hydrolysis of N-vinylformamide is 100%.

EXAMPLE 2

Method for producing polyvinyl alcohol with a primary aminovymi functional groups using 4-aminobutyraldehyde (12 mol.% Amin)

Poly(vinyl alcohol) (Airvol 107) dissolved in water (270 ml) at 70°With N2. After dilution of the reaction together with an additional amount of water (20 ml) was injected concentrated hydrochloric acid (16,34 g, 0,170 mol.) and 4-aminobutyraldehyde (AWAA) (18,14 g, 0,136 mol.). The reaction is carried out at 75°C for 6 hours and ZAT is m is cooled to room temperature. The obtained polymer produce precipitation in acetone, washed with additional acetone and dried in a vacuum oven (60°C/1 Torr). The composition of the obtained polymer with13With NMR was defined as containing 12 mol.% 4-aminobutyrate.

EXAMPLE 3

The coating adhesive strength

Several coatings, pigmented silica receive the usual way to determine the adhesive strength of the coating; however, one type contains a homopolymer of polyvinyl alcohol and another type copolymer PVOH/PVNH2as a binder. The coating composition includes 100 parts of precipitated silica pigment and 40 parts of polyvinyl alcohol brand "Avirol 125" (125) - in one case; and polyvinyl alcohol with aminovymi functional groups according to Example 1, in which the PVOH/PVNH2, MMW (srednevekovaja molecular mass of approximately 110000), contains 12 mol.% Amina - in another case; then, this coating composition is applied to paper, and the approximate coating weight is 6 g/sq.m. During the preparation of coatings of polyvinyl alcohol dissolved in water to a concentration of about 10 wt.% the solids. Then enter the pigment. The test is carried out in the device IGT model AIC2-5 after execution methods T514 TAPPI. The higher the value, the higher the strength of the coating. Table 1 shows the conditions and results.

Table 1

Check (held device IGT) strength

on plucking coating containing PVOH homopolymer

and PVOH copolymer/PVNH2
SampleIGT strength plucking
40 part a 125 (99,3% hydrolyzed MMW PVOH16,87
40 parts 12 mol.% MMW PVOH/PVNH227,83
1MMW PVOH means the average molecular weight or srednevekovoy molecular weight of 110,000;

2MMW PVOH/PVNH2means the average molecular weight or srednevekovoy molecular weight 96000.

The results show that the copolymer of vinyl alcohol/vinylamine containing 12 mol.% hydrolyzed N-vinylformamide, provides higher strength plucking than PVOH homopolymer, thereby demonstrating the improved binder properties of the coating for inkjet printing according to the presence of the primary amine.

EXAMPLE 4

The optical density of the printed ink

At the core sheets uncoated coated to determine the optical density of ink jet printing. The optical density is determined by several colors. One group of core sheets coated ink jet printing, consisting of PVOH and silica PI is ment; another group coated for inkjet printing, comprising 6 mol.% MMW PVOH/PVNH2and silica pigment, using a spiral roll and tip of the scraper. The level of binder is from 70 weight parts to 30 weight parts per 100 weight parts of silica. Coating weight in the range from 4 to 6 g/sq.m. After coating and drying the sheets printed using an inkjet printer Hewlett Packard 560 test sample Hewlett Packard to scan paper-based inkjet printing. The optical density of the printed samples measured by the densitometer to measure the optical density of the reflected light model "Tobias IQ 200".

Figure 1-5 compare the optical density of ink on the coating for inkjet printing with a binder copolymer PVOH/PVNH2relatively coatings for inkjet printing with standard PVOH binder. On these Figures:

* 100% PVOH means that the coating composition for inkjet printing, the silica is completely absent.

Polyvinyl alcohol Airvol 125 hydrolyzed at 99.3% and its molecular weight (Mw) is 100000.

Polyvinyl alcohol Airvol 325 hydrolyzed to 98,0% and its molecular weight (Mw) - 110000.

Polyvinyl alcohol Airvol 523 obtained on 88,0% and its molecular weight (Mw) - 110000.

PVOH/PVAm - another abbreviation for PVOH/PVNH2: polyvinyl alcohol with aminovymi functional groups an example1.

Figure 1 shows that the optical density of the monochrome jet inks for coated paper for inkjet printing containing PVOH binder/PVNH2exceeds coated paper for inkjet printing containing polyvinyl alcohol, in all cases except for the largest of loads. On the other hand, the coating on the basis of PVOH/PVNH2remained essentially constant at all levels.

Figure 2 shows that at low levels of binding to silica PVOH/Vam exceeds PVOH, thereby demonstrating increased strength of the action of the binder.

Figure 3 compares the optical density of the Magenta ink of different coatings, and in particular shows that the copolymer PVOH/VAm in all categories exceeds PVOH, and especially at low levels of binder to pigment.

According to Figure 4 a binder in the form of polyvinyl alcohol/polyvinylene has significantly better performance compared to the PVOH according to the test results of optical density yellow. Compared with the previous test optical density: significantly better results were obtained with polyvinyl alcohol with aminovymi functional groups at all levels.

According to Figure 5 is comparable results were obtained with a binder PVOH/VAm at high loads, but at lower loads demonstrated superior properties.

EXAMPLE 5

Water resistance

The water resistance of the ink printed on coated paper for inkjet printing with PVOH/PVNH2as a binder, were compared with the coated paper of homopolymer PVOH. The audit was conducted first by measuring the optical density of the monochrome black after printing. The printed area was then immersed in distilled water for 30 seconds and then dried on a hot plate under tension. The optical density was then measured again. The results are shown in Table 2.

Table 2

The resistance of inkjet papers

coated with a binder in the form of PVOH and PVOH/PVNH2< / br>
Δindicates the difference of optical density

between paper products before and after wetting
Type PVOH

Parts PVOH to 100 parts of the silica pigment
The optical density of the monochrome black to wettingThe optical density of the monochrome black after wettingΔoptical density
99.3% of the hydrolysis

average MW, 30 parts
1,330,83-0,50
98,0% hydrolysis, average MW, 30 parts1,361,07-0,29
88,0% hydrolysis, average MW, 30 parts1,360,96-0,40
6 mol.% PVOH/PVNH2average MW, 30 partsthe 1.441,35-0,09
6 mol.% PVOH/PVNH2average MW, 50 pieces1,411,36to-0.05
6 mol.% PVOH/PVNH2average MW, 70 parts1,301,30-0,0
12 mol.% PVOH/PVNH2average MW, 40 parts1,421,42-0,0

Table 2 shows that the resistance of the printed ink increases when printing on paper products coated for inkjet printing on the basis of silica containing polyvinyl alcohol with aminovymi functional groups. From the point of view binder these results indicate that the loss of optical density after wetting decreases with level 6 mol.% PVOH/PVNH2in the coating. These results also show that the coating for inkjet printing containing 12 mol.% PVOH/PVNH2,increases resistance as compared with a copolymer of 6 mol.% PVOH/PVNH2at approximately equal levels of administration.

EXAMPLE 6

Rheology of coatings for inkjet printing

Several coating compositions for ink-jet printing were prepared using different connections is relevant, in order to determine their influence on the rheology of the resulting compositions for inkjet printing. Graph (Fig.6) shows the shear characteristics depending on viscosity for coating with 13% solids content, with the coating composition: 100 parts of silica and 40 parts binder. Were used the following four types of binder:

1. Fully hydrolyzed with an average molecular weight PVOH (FH MMW); approximate molecular weight equal to 110000.

2. Partially hydrolyzed with an average molecular weight PVOH (PHNH2MMW); approximate molecular weight equal to 110000.

3. PVOH/PVNH2with an average molecular weight, 6 mol.% salt HCl; approximate molecular weight equal to 95000.

4. PVOH/PVNH2with an average molecular weight of the free base in the amount of 12 mol.%; the approximate molecular mass equal to 96000.

Shear viscosity of the coatings was measured "Capillary viscometer strong shift ACAV" at temperatures of 35-40°C.

Results according to Fig.6 show that coatings for inkjet printing on the basis of silica and binder in the form of a copolymer of poly(vinyl alcohol)/vinylamine show a much lower viscosity characteristics compared to coatings for inkjet printing with homopolymers poly(vinyl alcohol) as a binder. The mechanism with which to achieve characteristics viscosity at a strong shift is unknown, but it can be explained by the high degree of absorption of PVOH with aminovymi functional groups on the surface of the silica pigment. It is believed that a higher degree of absorption of the copolymer on the surface of the silica will not allow the polymer chains to pass into the liquid phase of the coating and thereby lower the overall viscosity of the coating. The obtained data confirm the assumption that with increasing amine content in the binder absorption will increase and characteristics of thickening shear will decrease.

EXAMPLE 7

The lightfastness

To determine the lightfastness of compositions were prepared several compositions for inkjet printing. The table below shows the lightfastness UV-radiation sheets, printed inkjet printing and coatings based on 100 parts of precipitated silica pigment. The light fastness was determined by measuring the optical density of the printed ink-jet printing paper before and after a 54-hour exposure to UV light radiation. The optical density of the paper was measured by a densitometer to measure the optical density of the reflected light model "Tobias IQ 200". Then the printed sheets were subjected to UV-light radiation using a test device of accelerated atmospheric aging "Q-U-V". The obtained values are registered and given the us in table 3; Δ represents the difference in optical density between the source and the tested samples; the lower the value, the better the resistance.

Table 3

The lightfastness of homopolymer PVOH

compared with PVOH copolymer/PVNH2< / br>
The difference in optical density between the original sample and the sample after a 54-hour exposure to

UV light radiation

Δ characterizes the difference of optical density

after 54 hours exposure
Part of the binding:

100 parts of silica
Monochrome blackMagentaYellowBlueComposition-Noah black
30 parts of PVOH,

98,0% hydrolysis, average MW
Δ=0,26Δ=0,65Δ=0,16Δ=1,00Δ=0,33
30 parts

PVOH/PVNH2, 6 mol.% MMW
Δ=0,11Δ=0,52Δ=0,12Δ=1,08Δ=0,25
50 pieces

PVOH/PVNH2,

6 mol.% MMW
Δ=0,11Δ=0,41Δ=0,10Δ=0,92Δ=0,20
70 parts

PVOH/PVNH2< / br>
6 mol.% MMW
Δ=0,14 Δ=0,29Δ=0,08Δ=0,82Δ=0,21
40 parts

PVOH/PVNH2,

12 mol.% MMW
Δ=0,15Δ=0,25Δ=0,08Δ=0,79Δ=0,18

The results demonstrate that the lightfastness of printed color inkjet printing has improved when using PVOH copolymer/PVNH2as a binder for coatings for inkjet printing compared using homopolymer PVOH/PVNH2as a binder for coatings for inkjet printing. The light resistance is also improved with increasing level of PVOH/PVNH2-the binder in the coating and also at high amine content in the main chain of the copolymer. The mechanism of improving the light fastness is unknown, but may be explained by the increased resistance of the complex salt formed between sulfoxylate groups of the dyes used in the dye and the amine in polyvinyl alcohol with aminovymi functional groups.

EXAMPLE 8

The drying time

The prepared coating compositions for ink jet printing have different % of hydrolysis of different PVOH-binding and compared against the drying time of the paint (the time during which the paint dry after it was printed by inkjet printer) with the same status the PTO, which contains PVOH/PVAm-binding average molecular weight in the amount of 12 mol.%. The coating consists of 100 parts of precipitated silica pigment with 40 parts of PVOH or PVOH/PVAm-binder prepared with a total content of solids in the amount of 15%. The composition is applied spiral valikamam scraper on a paper basis weight of the coating is from 7 to 8 g/sq m

Paper coated with the coating was tested for drying time of paint in accordance with the regulations "Hewlett Packard Paper Acceptance Criteria For the HP Deskjet 500C, 550C & 560C Printers". The results are shown in Fig.7, where:

PH MMW - 87% hydrolysis at an approximate average molecular weight of 110,000;

IH MMW - 96% hydrolysis at an approximate average molecular weight of 110,000;

SH MMW - 87% hydrolysis at an approximate average molecular weight of 110,000; and

PVOH/PVAm - 12 mol.% vinylamine an approximate average molecular weight of 95000.

Fig.7 shows the improvement in drying time of the composition of inkjet printing containing PVOH/PVAm, in comparison with compositions containing the copolymer PVOH.

EXAMPLE 9

The inkjet paper impregnated with

Paper received in accordance with the General method of U.S. patent No. 4880497: the paper was impregnated with a binder prior to coating, not by coating on the surface of the paper. The task is to determine whether the provide for comparable properties inkjet printing by impregnation compared to the floor, - in addition to increasing the strength of the paper in wet and dry conditions.

The second task is the replacement of polyvinyl alcohol with aminovymi functional groups, i.e. hydrolyzed vinyl acetate/N-vinylformamide on manufactured quaternionic polyvinyl alcohol.

The paper is produced by the introduction of a water binder in the base paper in the size press - in contrast to the application of binder to the surface of the paper as a paper coating. In this case, applying the following three ways:

1. Get three sheets to the basics: one without coatings, another coating of polyvinyl alcohol, and the one with a coating of polyvinyl alcohol with aminovymi functional groups. Silica is associated with the paper by means of a binder; in the absence of binder silica was not used.

2. Get three sheets in accordance with the above claim 1; with the exception that the paper is subjected to surface sizing (impregnation) of polyvinyl alcohol prior to coating of polyvinyl alcohol or polyvinyl alcohol with aminovymi functional groups.

3. Get three sheets in accordance with the above paragraph 2; except that the paper is subjected to surface sizing of polyvinyl alcohol with aminovymi functional groups prior to coating ratio is ejstvujuschij binder. The results are given in Fig, 9 and 10.

SUMMARY of RESULTS

Surface sizing of the paper base with 12 mol.% PVOH/VAm average molecular weight improved levels of optical density (one of the indicators of the printing properties of ink-jet printing) compared to leaves with surface sizing using homopolymer Airvol 523 and compared with paper-based without surface sizing (Fig). But the results show that by applying the binder in the coating compared to the impregnation quality inkjet printing is significantly increased. Between the optical density on the paper coated with PVOH/PVNH2and an optical density of paper impregnated or coated PVOH/PVNH2the difference, apparently, is small. Water paint three types of paper was very similar (see Fig.9). Sheets with surface impregnation of polyvinyl alcohol Airvol 523 provided a higher level of strength of the paper in a dry condition compared to the PVOH/VAm. Both sheets with surface impregnation offer a higher strength than the leaf-base.

EXAMPLE 10

This example compares the inkjet paper coated PVOH binder/PVNH2water-based and paper coated cationic polyvinyl alcohol manufactured by Kuraray company, a cationic polymer S. The results are presented in figure 11 and 1.

11 shows that the coating of the carrier sheet coated with 100 parts of silica pigment and 40 parts PVOH/VAm provides the optical density of paint, much more than the coverage with 100 parts of the silica pigment or with 40 parts of Airvol 523, or 40 parts of cationic polymer S "Kuraray". All samples coated paper deliver the levels of optical density exceeding that of the sheets, which had only a surface sizing. Fig shows that the resistance of the paint was very good with PVOH/VAm-coating and very low when using polyvinyl alcohol "Airvol 523" and cationic polyvinyl alcohol "Kuraray". Strength in the dry state, all the sheets are coated was approximately equal to and slightly above the strength of the carrier sheet. Strength in dry condition sheets coated compared to sheets with surface sizing was much smaller.

EXAMPLE 11

Paper for inkjet printing using 4-aminobutyraldehyde derivative of polyvinyl alcohol

Was performed by the method of Example 2 for the preparation of 4-aminobutyraldehyde derivative of polyvinyl alcohol - except that the polymer contains amine functionality in the value of 7 mol.%. Comparison was made with polyvinyl alcohol as a binder and other alcohols having amine functional groups is, obtained by hydrolysis of a copolymer of vinyl acetate/N-vinylformamide, had mentioned the amine functionality in mol.%. The results are given in Fig.

The results show that the indicators of each of the polyvinyl alcohols with aminovymi functional groups exceeded the indicators of polyvinyl alcohol. This Fig also shows that 7% of the amine functionality was equivalent systems functional hydrolyzed polymer of vinyl acetate/N-vinylformamide with the content 12 and 18 mol.%.

Briefly, polyvinyl alcohols with aminovymi functional groups provide good properties for coatings for inkjet printing paper and, in particular, for those coatings for inkjet printing, which was silica. In almost every case, the properties were improved compared with polyvinyl alcohol. When comparing the binding in the form of polyvinyl alcohol/polyvinylene: amine content of 12 mol.% turned out to be better amine with a content of 6 mol.%. It is believed that this fact suggests that Amin provides cationic positions on the main chain of the polymer reacting with the ink jet printer, and thus increases the optical density of the ink, water colors and light fastness of the dye. The higher the content of amine, the better the performance. The amino group increases with asiausa characteristics of the binder and silica. It was also observed that 4-aminobutyrate derivative of polyvinyl alcohol gives slightly better results for vinyl acetate/N-vinylformamide polymers. It is believed that the reason for this circumstance is that the primary amino groups have the form of elongated side chains extending from the main chain of the polymer; thus hydrolyzed N-vinylformamide group closely linked to the main chain of the polymer. Consider that the side chains provide aminoven cationic sites improved access to the paint and also provide Amin able to easily connect with silica.

1. Paper for inkjet printing on the surface of which is applied the coating composition for ink-jet printing containing a mineral pigment and a polymer binder, water-based, characterized in that as the polymeric binder used polyvinyl alcohol with a primary aminovymi functional groups, where the functionality of the primary amine in the specified polyvinyl alcohol with aminovymi functional groups is approximately from 1 to 30 molar percent, and polyvinyl alcohol with a primary aminovymi functional groups selected from the group consisting of a hydrolyzed copolymer of vinyl acetate and N-vinylamide, the copolymer of vinyl acetate is not grafted copolymer; hydrolize the data of a copolymer of vinyl acetate and allylamine, when the vinyl acetate copolymer is grafted copolymer; aminoalkylindole derivative of polyvinyl alcohol, and the coating composition for ink-jet printing applied to the surface in the approximate amount of 2 to 20 g/m2.

2. Paper according to claim 1, where the mineral pigment is silica.

3. Paper according to claim 1, where the polyvinyl alcohol with a primary aminovymi functional groups is aminoalkylsilane derivative of polyvinyl alcohol.

4. Paper according to claim 3, where the polyvinyl alcohol with a primary aminovymi functional groups is 4-aminobutyrate polyvinyl alcohol.

5. Paper according to claim 1, where the polyvinyl alcohol with a primary aminovymi functional groups is hydrolyzed copolymer of vinyl acetate and allylamine.

6. Paper according to claim 1, where the polyvinyl alcohol with a primary aminovymi functional groups is hydrolyzed copolymer of vinyl acetate and N-vinylamide.

7. Paper according to claim 6, where the specified N-vinylamide is N-vinylformamide.

8. Paper according to claim 6, where the specified N-vinylamide is N-vinylacetate.

9. Paper according to claim 1, where the silica is present in an approximate amount of from 30 to 85 wt.% coating composition for inkjet printing.

10. Paper according to claim 1, where the binder is included in the coating composition for inkjet printing in approximate quantities is from 20 to 80 wt.%.

11. Paper according to claim 1, where the copolymer of polyvinyl alcohol and polivinilbutilovy polymer is a hydrolyzed copolymer of vinyl acetate and N-vinylamide.

12. The paper of claim 10, where the hydrolyzed copolymer mainly composed of hydrolyzed vinyl acetate and N-vinylformamide and hydrolyzed vinyl acetate is present in an amount of about 80 to 95 mole percent.

13. Paper according to claim 1, where the polyvinyl alcohol with aminovymi functional groups is 4-aminobutyrate polyvinyl alcohol.

14. Paper according to claim 1, where the polyvinyl alcohol with aminovymi functional groups is hydrolyzed copolymer of vinyl acetate and allylamine.

15. The method of producing sheet used for recording information, which are coated inkjet paper-based, with the specified coating for inkjet printing includes a polymeric binder and a mineral pigment, characterized in that as the polymeric binder used polyvinyl alcohol with a primary aminovymi functional groups and polyvinyl alcohol with a primary aminovymi functional groups selected from the group consisting of a hydrolyzed copolymer of vinyl acetate and N-vinylamide, the copolymer of vinyl acetate is not grafted copolymer; from hydrolyzed copolymer of vinyl acetate and allyl is in, when the vinyl acetate copolymer is grafted copolymer; and from aminoalkylindole derivative of polyvinyl alcohol, and the coating composition for ink-jet printing applied to the surface in the approximate amount of 2 to 20 g/m2.

16. The method according to clause 15, where the mineral pigment is silica.

17. The method according to clause 15, where polyvinyl alcohol with a primary aminovymi functional groups selected from the group consisting of a hydrolyzed copolymer of vinyl acetate and N-vinylamide, hydrolyzed copolymer of vinyl acetate and allylamine, and aminoalkylindole derivative of polyvinyl alcohol.

18. The method according to 17, where the silica is present in an approximate amount of from 30 to 85 wt.% coating composition for inkjet printing.

19. The method according to 17, where the binder is included in the coating composition for inkjet printing in the approximate amount of from 20 to 80 wt.%.

20. The method according to clause 15, where the copolymer of polyvinyl alcohol and polivinilbutilovy polymer is a hydrolyzed copolymer of vinyl acetate and N-vinylamide.

21. The method according to claim 20, where the hydrolyzed copolymer essentially composed of a hydrolyzed vinyl acetate and N-vinylformamide and hydrolyzed vinyl acetate is present in an approximate amount of from 80 to 95 mole percent.



 

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FIELD: process of production of paper having a specific coating, applicable for spray printing.

SUBSTANCE: a coating composed of polyvinyl alcohol with primary amine functional groups and mineral pigment is applied onto the paper surface.

EFFECT: improved quality of paper for spray printing.

21 cl, 13 dwg, 3 tbl, 11 ex

FIELD: paper-and-pulp industry.

SUBSTANCE: invention relates to pigment, which can be used in manufacture of paper with filler, coated paper, and cardboard. Calcium hydroxide and calcium carbonate powders taken in proportion between 1.0:2.2 and 1.0:23.5 are added to vigorously stirred water, after which temperature of mixture is raised to 80-85°C and resulting reaction mixture is kept being stirred for 90-180 min to form dispersion of pigment containing 20-35% solids.

EFFECT: improved quality of pigment at lower cost and extended application area.

3 tbl

FIELD: pulp and paper industry; methods of production of the pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. In the water at intense stirring feed powders of calcium hydrate and calcium carbonate at the ratio of the indicated components accordingly from 1.0:2.2 up to 1.0:12.9. The produced suspension is gradually added with aluminum sulfate at its ratio to the total mass of the calcium hydroxide and calcium carbonate from 1.0:0.85 up to 1.0:4.30. Then the temperature of the mixture is increased up to 8О-85°С and the produced reaction mixture is kept at stirring within 90-180 minutes with formation of the dispersion of the pigment with the share of the dry substances in it equal to 20-35 %. Then the dispersion is dried and grinded into the powder. The powder is dispersed in the water containing the given amount of the dissolved coolant and-or binding - starch or polyvinyl alcohol. The technical result of the invention production of the pigment with the new properties, that allow to expand the field of its application at manufacture of various types of the cardboard and the paper.

EFFECT: the invention ensures production of the pigment with the new properties, expansion of the field of its application at manufacture of various types of the cardboard and the paper.

2 tbl

FIELD: pulp and paper industry; methods of production of the composite pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the composite pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. Calcium hydroxide is mixed with kaolin and added with aluminum sulfate in the aqueous medium at stirring. The aqueous medium contains the binding chosen from the group, which includes starch and polyvinyl alcohol in amount of 1.5-5.0 % from the mass of the absolutely dry pigment, and-or the water soluble colorant in amount of 0.1-0.5 % from the mass of the absolutely dry pigment. The technical result of the invention is the improvement of the composite pigment quality and expansion of its field of application.

EFFECT: the invention ensures improvement of the composite pigment quality and expansion of the field of its application.

2 tbl

FIELD: pulp and paper industry; methods of production of the pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. Calcium hydroxide suspension is treated with aluminum sulfate solution in the aqueous medium at stirring. The treatment is conducted in the aqueous medium containing the binding in the dissolved state. The binding is chosen from the group, which includes starch and polyvinyl alcohol in the amount of 0.5-5.0 mass % from the mass of the absolutely dry pigment, and-or the colorant in the amount of 0.1-0.5 mass % from the mass of the absolutely dry pigment. The technical result of the invention is the improved quality of the pigment and expansion of its field of application.

EFFECT: the invention ensures the improved quality of the pigment and expansion of the field of its application.

2 tbl

FIELD: pulp and paper industry; methods of production of the pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. Calcium carbonate is treated with aluminum sulfate in the aqueous medium. The treatment is conducted at aluminum sulfate consumption of 25-105 % to the mass of absolutely dry calcium carbonate at the temperature of 80-85°С during 90-180 minutes with production of the suspension containing 25-35 % dry substances in it. At that they use the aqueous medium containing the binding chosen from the group, which includes starch and polyvinyl alcohol in the amount of 0.5-3.0 mass % from the mass of the absolutely dry pigment, and-or the water soluble colorant in the amount of 0.1-0.5 mass % from the mass of the absolutely dry pigment. The suspension is additionally dried and grinded. The technical result of the invention is the improved quality of the pigment as well as expansion of its field of application.

EFFECT: the invention ensures the improved quality of the pigment as well as expansion of its field of application.

2 tbl

FIELD: paper coated with composition for coating various kinds of paper, for offset printing of paper used for manufacture of books, magazines, annual reports, or packaging paper.

SUBSTANCE: composition comprises pigments and binder. Composition pigments are formed as microballs having sizes below 10 micrometers, preferably about 7 micrometers. Paper coated with such composition is silky by touch and has at least one surface coated with such composition, preferably both of its surfaces. This paper may be tracing paper.

EFFECT: improved quality of paper owing to preventing sliding thereof during separation of sheets in stacks, delamination of coating during printing process and, accordingly, elimination of paper dusting and formation of impure imprints.

7 cl, 2 dwg, 2 tbl, 13 ex

FIELD: pulp-and-paper industry.

SUBSTANCE: coating composition consisting of ink-compatible pigment, water-soluble binder, and cationic fixative is deposited onto one of the sides of based paper and the other side is covered with detwisting coating, after which glossy surface is formed. Coating composition is supplemented by wettability controlling agent based on polydimethylsiloxane resins in amounts 0.4 to 1.6% of the weight of pigment. Water-soluble binder is a mixture of polyvinyl alcohol with polyvinylpyrrolidone at ratio (90-50):(10-50) in amount 40-60% and styreneacrylic latex in amount 15-20% of the weight of pigment. When forming glossy surface, polyethylene oxide-based plasticizer is used in amount 7-15% of the weight of pigment followed by supercalendering at pressure in roll contact zone 20-25°C and temperature 50-90°C.

EFFECT: improved manufacturability of process.

5 cl, 1 tbl, 54 ex

FIELD: pulp-and-paper industry.

SUBSTANCE: coating composition consisting of ink-compatible pigment, binder, and cationic fixative is deposited onto one of the sides of based paper and the other side is covered with detwisting coating, after which coating is ennobled by means of supercalendering. As pigment, mixture of amorphous silicon dioxide with calcium carbonate or kaolin with outer specific surface 60-85 m2/g at ratio (25-50):(75-50). Binder is a mixture of polyvinyl alcohol with latex selected from class of styreneacrylic copolymers at ratio (20-25%):(7-18%) based on the weight of pigment. Cationic fixative is poly(diallyldimethylammonium chloride), which is directly incorporated into coating composition in amount 5-10%.

EFFECT: enabled image quality and paper surface strength control.

3 cl, 1 tbl, 13 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: process of production of paper having a specific coating, applicable for spray printing.

SUBSTANCE: a coating composed of polyvinyl alcohol with primary amine functional groups and mineral pigment is applied onto the paper surface.

EFFECT: improved quality of paper for spray printing.

21 cl, 13 dwg, 3 tbl, 11 ex

FIELD: paper-and-pulp industry.

SUBSTANCE: invention relates to pigment, which can be used in manufacture of paper with filler, coated paper, and cardboard. Calcium hydroxide and calcium carbonate powders taken in proportion between 1.0:2.2 and 1.0:23.5 are added to vigorously stirred water, after which temperature of mixture is raised to 80-85°C and resulting reaction mixture is kept being stirred for 90-180 min to form dispersion of pigment containing 20-35% solids.

EFFECT: improved quality of pigment at lower cost and extended application area.

3 tbl

FIELD: pulp and paper industry; methods of production of the pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. In the water at intense stirring feed powders of calcium hydrate and calcium carbonate at the ratio of the indicated components accordingly from 1.0:2.2 up to 1.0:12.9. The produced suspension is gradually added with aluminum sulfate at its ratio to the total mass of the calcium hydroxide and calcium carbonate from 1.0:0.85 up to 1.0:4.30. Then the temperature of the mixture is increased up to 8О-85°С and the produced reaction mixture is kept at stirring within 90-180 minutes with formation of the dispersion of the pigment with the share of the dry substances in it equal to 20-35 %. Then the dispersion is dried and grinded into the powder. The powder is dispersed in the water containing the given amount of the dissolved coolant and-or binding - starch or polyvinyl alcohol. The technical result of the invention production of the pigment with the new properties, that allow to expand the field of its application at manufacture of various types of the cardboard and the paper.

EFFECT: the invention ensures production of the pigment with the new properties, expansion of the field of its application at manufacture of various types of the cardboard and the paper.

2 tbl

FIELD: pulp and paper industry; methods of production of the composite pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the composite pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. Calcium hydroxide is mixed with kaolin and added with aluminum sulfate in the aqueous medium at stirring. The aqueous medium contains the binding chosen from the group, which includes starch and polyvinyl alcohol in amount of 1.5-5.0 % from the mass of the absolutely dry pigment, and-or the water soluble colorant in amount of 0.1-0.5 % from the mass of the absolutely dry pigment. The technical result of the invention is the improvement of the composite pigment quality and expansion of its field of application.

EFFECT: the invention ensures improvement of the composite pigment quality and expansion of the field of its application.

2 tbl

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