Composition to make chalk overlay paper

FIELD: textile; paper.

SUBSTANCE: composition contains a fibrous mixture from chemical and thermomechanical mass and cellulose. The fibrous mixture contains birch leached chemical and thermomechanical mass with extent of grinding 60-125 ml (CSF) and cellulose with grinding extent of 350-500 ml (CSF) at the specified ratio of components. The cellulose in the fibrous mixture is a leached pine sulfate cellulose and/or pine sulphite cellulose, or pine cellulose, and/or leaf cellulose.

EFFECT: expansion of leaf-bearing soft woods due to using birch leached chemical and thermomechanical mass to prepare a fibrous semi-finished product to produce paper with high physical mechanical indices to ensure extent of whiteness.

3 cl, 1 tbl

 

The invention relates to the pulp and paper industry, to the composition of the paste for the production of coated paper grades that require high quality base paper, in particular, may be used upon receipt of LWC paper.

Famous paper pulp for the manufacture of base paper used for covering with plywood in A.S. No. 1756442, D21H 11/10, 1992. Paper pulp contains 25-45% sulfate bleached softwood pulp, 5-20% thermo-mechanical or chemi-thermomechanical pulp from spruce or fir and aspen wood chips, and sulfate bleached hardwood pulp. Refining of bleached Kraft softwood and hardwood pulp produced separately, to the extent of the grinding °W: coniferous 26-28, deciduous 28-32. The disadvantage is the low degree of whiteness of the resulting paper, the limited use of natural forest resources for its production.

Known fibrous material for the manufacture of paper used for food packaging machines in A.S. No. 996596, D21H 3/00, 1983. The mass contains cellulose and thermo-chemical-mechanical wood pulp obtained by chemical treatment of wood chips with a mixture of carbonate or sodium bicarbonate, caustic soda and sodium sulfide. Thermomechanical wood pulp produced from wood chips hardwood, a mixture of deciduous and coniferous wood and one coniferous wood. Fault the mi are the low degree of whiteness and strength of paper derived from the fibrous mass.

As the closest analogue of the claimed technical solution of the invention selected for A.S. No. 632790, D21H 3/00, 1978. Fibrous material for the manufacture of paper, intended for packaging and packing of food products machines, contains 30-50 wt.% pulp and 50-70 wt.% deciduous thermochemical refiner wood pulp. Thermochemical wood is produced by grinding aspen chips on a disk mill with advanced chemical and thermal treatment. The disadvantage is the low degree of whiteness of the resulting paper through the use of aspen chips, giving the yellow paper. In addition, restrictions on the use of hardwood only wasp leads to suboptimal use of resources hardwoods on the territory of the Russian Federation. Low characteristics of the resulting mass, such as strength and whiteness, prevent the use of pulp for the manufacture of coated paper.

The technical task of the invention is the expansion of a number of hardwoods used to obtain paper with high physical-mechanical parameters.

The technical result is to obtain the possibility of applying hardwoods, in addition to aspen, while providing a degree of whiteness and strength sufficient for the Holocene coated paper.

The technical result is ensured by the fact that in the composition for the production of coated paper containing fibrous mixture of chemi-thermomechanical pulp and cellulose, according to the invention, the fibrous mixture contains birch bleached chemi-thermomechanical mass with the degree of grinding 60-125 ml (CSF) and pulp with a beating degree of 350-500 ml (CSF) in the following ratio, wt.%:

birch bleached chemical thermo mechanical pulp60-95
cellulose5-40.

As cellulose composition contains bleached coniferous sulphate pulp and/or coniferous sulphite pulp. Along with coniferous pulp composition may contain hardwood pulp.

The technical result is achieved due to the fact that the paper weight in addition to traditionally used softwood pulp contains birch bleached chemi-thermomechanical pulp (bhtm), which occupies a large part of 60-95 wt.% in the overall composition. The use of birch bhtm can significantly extend the possibilities of use of natural resources on the territory of Russia. The proportion of forested land with dominant trees on the territory of the Russian Federation is 13%, territorialism region 29%, including in the Kurgan region, 51%, Perm region - 24%, Chelyabinsk region - 47%, Bashkiria - 25%, Sverdlovsk region - 30% (Forest reference to the forests of the Urals, 1991). It is known that boyhoodparadise properties of softwoods higher compared to deciduous species. Their fibers are longer and more flexible, have better mechanical properties. Wood fibers are hollow cylinders. The length of the fibers of softwood is 2-4 mm, diameter 25 mm, length of birch fibers is about 1 mm, a diameter of 10 mm. Ability to interfiber sweathearting at coniferous fibres is higher than that of birch, due to the greater length and flexibility. Birch same fibers have thicker cylinder wall, which have a higher rigidity. The strength of paper from the fibers of birch wood is lower than the strength of the paper from softwood fibers. However, the degree of whiteness of the paper birch fibers are quite high due to the peculiarities chromophoric groups of birch lignin. Increasing the strength of paper made from paper pulp using birch bhtm, optimum degree of grinding of all components included in the composition. For fibrous semi-finished product of a mixture of birch bleached chemi-thermomechanical pulp, the degree of grinding is 60-125 ml (SF), for bleached softwood sulphate pulp - 350-500 ml (CSF). When the degree of grinding of fiber birch become flexible, elastic, thereby increasing the area of the coupling them with neighboring fibers, in addition, on the surface of birch fibers are formed of small hooks, so-called nano-fibrils, amplifying the degree of coupling with the neighbouring birch fibres and fibre sulphate pulp. The degree of grinding of these two components, mentioned above, also promotes better adhesion of birch fibers. Experimentally found that when the specified degree of grinding of all components of the strength of the resulting paper maximum. The change in the degree of grinding below these values leads to worse adhesion of the fibers, increasing the degree of grinding is to abrasion and fracture of the fibers. When the specified degree of grinding of all components of the content BHTM can vary in the range of 60-95 wt.%, this achieves the required degree of whiteness of the resulting coated paper. To ensure the strength of the paper using pulp in specified quantities at given degrees of grinding. In the composition for the production of coated paper mainly use bleached coniferous sulphate pulp. However, it may be partially or completely replaced by coniferous sulphite pulp, in addition to the war cellulose can be used cellulose deciduous.

Study of physico-mechanical properties of the experimental images showed that the introduction of an additional stage of refining and increasing the degree of grinding bhtm from 110 to 70 ml of CSF leads to an increase in the strength properties of the tear resistance and resistance to tearing, durability of the surface. Energy interfiber bonds has increased from 256 to 330 J/m2and exceeded the value of 280 J/m2for standard bhtm of softwood spruce. This is due to the appearance of micro - and nanofibrils on the surface of the fibers, additional free hydroxyl groups on the surface of the hemicelluloses and lignin, which are formed in the additional process stage grinding carried out with the use of modern grinding equipment, and provide linkages in the sheet at the level of micro - and nanofibrils. On the other hand, the shortening of the fibers in the milling process leads to the formation of fine fibers. Small fiber, in turn, fills the voids between the long fibers, thereby reducing the permeability and roughness.

The use of the claimed paper pulp in paper production with improved optical properties, such as whiteness and opacity while maintaining high bulk and required strength with a maximum content of birch bhtm, in the composition of the semi-finished product COI is lsout standard technology for the production of coated paper. The proposed composition allows to produce base paper at speeds of not less than 1700 m/min with good efficiency wire cloth. The strength of the paper allows you to sustain the data rate without interruption process due to web breaks. White birch bhtm is not less than 80% ISO, white bleached sulphate softwood pulp - not less than 87% ISO. The composition used to produce the fundamentals of LWC paper, allows to obtain a product with a high degree of whiteness is more than 80% ISO, low roughness and high mechanical strength. The content of filler and reinforcing additives does not exceed the level of existing light coated paper.

Comparative physico-mechanical characteristics of the paper produced using birch bhtm and using spruce bhtm shown in the table.

PropertiesContent BHTM in the composition of paper, %
birch 80birch 80spruce 65
The degree of grinding SCF according to the "canadian standard", ml11070 110
Weight paper with an area of 1 m2g565858
Thickness, microns717272
Resistance to tear, Nm/g
- machine direction607882
the transverse direction202521
Resistance to tearing, CMA2/g
- machine direction6,08,05,0
the transverse direction3,35,05,0
Energy interfiber relations, J/m2256330 280
Breathability on Bentsen, ml/min180160250
Roughness on Bentsen, ml/min facial/grid230/270180/220170/226
Roughness by Parker PPS 10, mm front/mesh6,5/a 5.45,7/6,15,1/6,2
The resistance of the surface to picking on Dennison, no front/mesh8/810/98/8
White ISO %848684
Opacity, %848185

Thus, the claimed invention allows to extend the use of hardwoods, due to the use of birch in the preparation of fibrous semi-finished product mixture bhtm while providing physical and mechanical properties required for the manufacture of coated paper.

1. Composition for the manufacture of the as coated paper, containing fibrous mixture of chemicomechanical pulp and cellulose, characterized in that the fibrous mixture contains bleached birch chemicomechanical mass with the degree of grinding 60-125 ml (CSF) and pulp with a beating degree of 350-500 ml (CSF) in the following ratio, wt.%:

birch bleached chemicomechanical weight60-95
cellulose5-40

2. The composition according to claim 1, characterized in that cellulose contains bleached coniferous sulphate pulp and/or coniferous sulphite pulp.

3. The composition according to claim 1, characterized in that cellulose contains coniferous pulp and/or hardwood pulp.



 

Same patents:
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FIELD: technological processes.

SUBSTANCE: invention relates to thermoplastic thermally expanding microspheres and their application. Microspheres contain a polymer shell made of monomers with ethylene unsaturation that encapsulates a propellant. Monomers with ethylene unsaturation contain from 20 to 80 wt % of acrylonitrile, from 20 to 80 wt % of monomers selected from the group that consists of acrylic acid ethers, from 0 to 10 wt % of methacrylonitrile, from 0 to 40 wt % of monomers selected from the group that consists of methacrylic acid ethers. The total quantity of acrylonitrile and acrylic acid ethers makes from 50 to 100 wt % as monomers with ethylene unsaturation. The propellant contains at least one representative selected from the group of methane, ethane, propane, isobutane, n-butane and isopentane.

EFFECT: microspheres have high ability of foaming, low Tstart without high quantities of halogen-containing monomers, resistance to chemicals and high transparency.

22 cl, 8 tbl, 28 ex

Microspheres // 2432202

FIELD: process engineering.

SUBSTANCE: invention relates to thermally expanding thermoplastic microspheres and their application. Said microspheres comprise polymer shell made from ethylenically unsaturated monomers that encapsulate propellent. Ethylenically unsaturated monomers comprise up to 20-80 wt % of acrylonitrile and 1-70 wt % of poly(vinyl alcohol) with single carbon-carbon olefinic linkage. Total amount of acrylonitrile and poly(vinyl alcohol) makes up to 100 wt % of ethylenically unsaturated monomers.

EFFECT: higher expansivity and chemical resistance, absence of halogen-containing monomers.

23 cl, 5 tbl, 45 ex

Micro spheres // 2432201

FIELD: process engineering.

SUBSTANCE: invention relates to thermally expanding thermoplastic microspheres and their application. Said microspheres comprise polymer shell made from ethylenically unsaturated monomers that encapsulate propellent. Ethylenically unsaturated monomers comprise up to 40-70 wt % of acrylonitrile and 5-40 wt % methylacrylonitrile, and 10-50 wt % of monomers selected from the group including acrylates, methacrylic esters and mixes thereof. Said propellent comprises at least one agent selected from the group including methane, ethane, propane, isobutene, n-butane and neopentane.

EFFECT: higher foaming capacity, expansivity and chemical resistance, absence of halogen-containing monomers.

21 cl, 6 tbl, 25 ex

FIELD: chemistry.

SUBSTANCE: composition contains at least one expandable microsphere and at least one ionic compound which is cationic. The composition also contains a certain set of cellulose fibres. The ionic compound is selected from a group comprising a polyamine, polyethyleneimine, colloid and sol. The colloid or sol contains at least one member from a group comprising silica, alumina, tin oxide, zirconium dioxide, antimony oxide, iron oxide and rare-earth metal oxides. The outer surface of the expandable microsphere, which is anionic, is not covalently bonded with an ionic compound. The composition has electrokinetic potential greater than or equal to 0 mV at pH of approximately 9.0 or less with ionic strength between 10-6 mol and 0.1 mol. The composition is prepared by bringing into contact at least one expandable microsphere and at least one ionic compound to form a mixture. The mixture is centrifuged to form a first phase containing at least one ionic compound and a second phase containing a particle. A solution containing a certain amount of cellulose fibre is also added. A low-density paper or cardboard base and article which is a cardboard container with good operational characteristics is obtained. The weight of the article is equal or less than 1 oz. The paper or cardboard base has Sheffield smoothness less than 250 units measured using a TARR1 T 538 om-1 technique, and colour speckling 2nd cyan not greater than 6. The base has Parker Print surface roughness from approximately 1.0 to 0.5, measured using a TARRI T 555 om-99 technique.

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28 cl, 5 dwg, 4 tbl, 2 ex

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25 cl, 3 tbl, 4 ex

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32 cl, 2 dwg, 3 tbl, 3 ex

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10 cl, 6 dwg, 2 ex

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29 cl, 25 dwg, 14 tbl, 8 ex

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17 cl, 16 dwg, 1 tbl, 3 ex

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.

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7 cl, 2 dwg, 2 tbl, 13 ex

Wipe product // 2430709

FIELD: medicine.

SUBSTANCE: wipe product relates to absorbent paper products. A wipe product represents a wipe sheet having a first side and a second side. The wipe sheet contains cellulose fibres in an amount at least 50 wt %, and an additional composition containing polymer. The additional composition is present at least on the first side of the wipe sheet. The wipe product has extensionality exceeding 3 cm3/g, a fluffiness test value less than approximately 3 mg, and the first side of the wipe sheet has a stick-slip value more than approximately 0.01. The additional composition contains a non-fibrous olefin polymer, ethylene carboxylic acid copolymer or their mixture. The additional composition can be included in a wipe cloth by means of fibre combination to be used for cloth formation. Alternatively, the additional composition can be superficially applied on the formed cloth.

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20 cl, 42 dwg, 18 tbl, 7 ex

FIELD: textile, paper.

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41 cl, 11 tbl, 89 ex, 35 dwg

FIELD: textile, paper.

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1 tbl, 8 ex

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32 cl, 2 dwg, 3 tbl, 3 ex

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14 cl, 4 dwg, 2 ex

FIELD: textile; paper.

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10 cl, 6 dwg, 2 ex

FIELD: medicine.

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33 cl, 10 dwg, 22 tbl

Composition // 2347030

FIELD: textiles; paper.

SUBSTANCE: composition is meant for improving the softness of paper products. Composition includes: (i) oil, fat or wax; (ii) at least one non-ionic surfactant; (iii) at least one anion compound, selected from anionic micro-particles and anionic surfactant; (iv) at least one polymer, which is a cation, non-ionic or amphoteric, where the non-ionic surfactant is added to the amount from about 60 to 1000 weight fractions for 100 weight fractions of the polymer. Composition is used in the method of manufacturing paper (versions). Method includes adding the mentioned composition to a cellulose suspension or to a moist or dry paper fabric.

EFFECT: increase in the quality of the paper products due to the increase in its softness, low resistance to tearing and high speed of getting wet and reduction in energy for pulping.

22 cl, 9 tbl, 9 ex

FIELD: chemistry.

SUBSTANCE: invention can be used for production of deposited calcium carbonate used as paper filler. Secondary particle diameter of deposited calcium carbonate is 1-10 mcm. Deposited calcium carbonate consists of aggregated primary particles of spindle calcium carbonate with greater particle diameter within 0.5 to 3.0 mcm, smaller diameter within 0.1 to 1.0 mcm with ration of specified diameters equal to 3 or more. Specific surface area BET of primary particles of calcium carbonate is 8-20 m2/g, cell volume is 1.5-3.5 cm3/g. Method of production of deposited calcium carbonate includes as follows. Carbon dioxide or carbon dioxide gas is injected in calcium hydroxide suspension concentrated 100-400 g/l, prepared by wet calcined liming activity of which 4 "н." HCl at third minute value is reduced to 150-400 ml. Reaction is resulted in carbonisation degree within 50 to 85%. Then 1 to 20 vol % of calcium hydroxide suspension is added. Reaction is complete with injection of carbon dioxide or carbon dioxide gas. The paper containing the specified calcium carbonate as filler is offered as well.

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7 cl, 2 tbl, 10 ex

FIELD: textiles, paper.

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EFFECT: increased quality of paper or cardboard due to increased smoothness, decreased hygroscopic expansivity, improved fold resistance and paper rolling resistance.

30 cl, 2 dwg, 3 tbl, 3 ex

FIELD: textile, paper.

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EFFECT: increased retention of filler in paper at simultaneous increase of paper strength index.

3 cl, 1 tbl, 4 ex

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