Method for reducing speed of photoyellowing

FIELD: textile, paper.

SUBSTANCE: method concerns reducing speed of photoyellowing of paper containing mechanical pulp. The method includes coating the surface of a paper sheet during papermaking of aqueous solution containing an effective amount of one or more salts of thiocyanic acid.

EFFECT: improvement of stability to photoyellowing of paper and cost-effective way while reducing its toxicity.

16 cl, 10 tbl

 

The technical field

This description relates to methods of reducing speed fotopoulou paper obtained from mechanical wood pulp.

The level of technology

Mechanical wood pulp can be used in compositions for the production of business papers, writing paper and high-quality securities for books that have a long service life and require that the paper did not turn yellow over time. Mechanical wood pulp include wood mass (DM), wood pulp from wood chips (DMS), thermomechanical wood pulp (TMDM), chemicomechanical wood pulp (TMDM), chemical-mechanical wood pulp (HMDM), their varieties (for example, DM, crushed stone crushers obtained under duress DM, thermo-DMD obtained under duress DMS obtained under duress TMDM, chemical DMS long HMDM, thermomechanical pulp); waste mass; and compositions containing mechanical, chemical wood and wastepaper pulp.

However, it is known that paper produced from mechanical wood mass, turn yellow during use. This yellowing limits their use in areas that require only a short service life of the paper. If the time before the yellowing of the paper can be increased, this would greatly expand the potential of the capacity market for bleached TMDM and TMDM; for example, the mixture could be more bleached TMDM and TMDM (for example, Kraft mechanical or sulfite mechanical mixture)used for the production of papers with a high degree of whiteness. Replacement of large quantities of the more expensive fully bleached at this low production of chemical pulp at a less expensive high-yield mechanical wood pulp promises significant economic benefits.

Photogelatine occurs mainly in the finished paper. I believe that photogelatine is due to radical photochemical reactions of residual lignin in the pulp. Therefore, the pulp with a high content of lignin and products containing such cellulose are the most susceptible to loss of white than the more expensive pulp with low lignin content. It seems that in this process, the radicals phenoxyl, hydroxyl, alkoxyl and peroxyl are intermediate. Accordingly, the scavengers of radicals and hydrogen donors/antioxidants provide protection from fotopoulou. Photoexcitation of alpha-carbonyl groups often trigger a chain of reactions involving radicals, and chemical modification of such groups, as well as absorption of light energy optical (ultraviolet) filters/absorbers significantly affect the discoloration. Known to the assy chemicals which provide limited protection from fotopoulou mechanical wood pulp include thiols, stable radicals nitroxide, sterically blocked hydroxylamine, phosphites, dieny, aliphatic aldehydes and UV filters. Usually the amount of chemical required for adequate protection, are economically feasible, and these substances usually have other undesirable traits, such as high toxicity and odor. Therefore, there is a need for non-toxic and cost-effective way to reduce the speed fotopoulou.

The invention

The present invention provides a method of reducing speed fotopoulou paper containing mechanical wood pulp: drawing on a sheet of paper in the paper manufacturing process of an aqueous solution containing an effective amount of one or more salts titanoboa acid.

Detailed description of the invention "Paper process" means a method of manufacturing paper products from pulp, including the establishment of the aqueous pulp composition for the manufacture of paper, the drainage of the composition to form a sheet and drying the sheet. The stage of formation of the composition to obtain paper, drainage and drying can be accomplished in any conventional manner known to experts in the field of engineering.

"Humidity is the first sheet of paper" - this paper, which has not been subjected drum dryer in the papermaking process.

"A dry paper sheet" is a sheet of paper which has undergone a drum dryer in the papermaking process.

"A.S." means absolutely dry.

"Add" - ethylenediaminetetraacetic acid.

"TPC" - diethylenetriaminepentaacetic acid.

"DMFC" - diethylenetriaminepenta (methylphosphonous acid).

As mentioned above, the present invention involves the application of an aqueous solution containing an effective amount of one or more salts titanoboa acid on the surface of a sheet of paper in the papermaking process. One of the embodiments of the invention an effective amount of salt is from 0.01 to 5 wt.% A.S. mass on the basis of 40% active solids; preferably from 0.05 to 1.0 wt.% A.S. mass on the basis of 40% active solids.

According to another embodiment of the invention the pH of the aqueous solution may be in the range from 3 to 9, preferably from 6 to 7.

According to another embodiment of the invention salt titanoboa acid selected from the group consisting of inorganic thiocyanates, sodium thiocyanate, potassium thiocyanate, ammonium thiocyanate and calcium thiocyanate.

According to another embodiment of the invention, the cations of these salts are selected from the group consisting of organic cations and not the content of inorganic fillers cations.

According to another embodiment of the invention an effective amount of one or more chemical substances, which are selected from the group consisting of chelating agents, optical brighteners, fluorescent dyes, UV absorbers and combinations thereof, can be added either individually or in a mixture with an aqueous solution containing an effective amount of one or more salts titanoboa acid. Another embodiment of the invention an effective amount of a chemical substance is from 0.01 to 5 wt.% A.S. mass on the basis of 40% active solids, preferably from 0.05 to 1.0 wt.% A.S. mass on the basis of 40% active solids.

According to another embodiment of the invention UV absorbers are selected from the group consisting of benzotriazole, benzophenone, inorganic oxides, organic particles and latex particles. For specialists, the term UV absorbers is synonymous with UV filters.

According to another embodiment of the invention the chelating agents are selected from the group consisting of add, DTPC and DMFC.

According to another embodiment of the invention optical brighteners are selected from the group consisting of substituted, stilbene-, Tetra - and hexachloro acids, creatinineclearance acids, dicyano-1,4-bis-stilbestrol, bisbenzimidazole, bis(creatininemia)stilbene, molten sulfonated p is aromaticheskikh (multi-core) compounds and distilbene.

According to another embodiment of the invention an aqueous solution containing an effective amount of one or more salts titanoboa acid, is mixed with a chelating agent in the ratio of from 1:100 to 100:1 based on active solids.

According to another embodiment of the invention an aqueous solution is from about 10% to 60% aqueous solution of active material including sodium thiocyanate or ammonium thiocyanate, or a mixture of these sodium thiocyanate or ammonium thiocyanate with a chelating agent selected from the group consisting of add, DTPC and DMFC in the ratio from about 1:100 to 100:1.

The aqueous solution can be applied on damp sheet of paper or on a dry sheet of paper, using known in the field of paper production method. For example, application of a water solution on a damp paper sheet can be performed using a spray nozzle, which is located near the desirable area of wet paper sheet.

According to another embodiment of the invention an aqueous solution is applied to the paper sheet by applying a specified aqueous solution on the surface of the partially dewatered sheet in the papermaking process before he gets on the first clothes dryer. Another embodiment of the invention an aqueous solution is applied to the paper sheet by applying a specified aqueous solution press on teaching is TKE specified papermaking process or after it.

According to another embodiment of the invention an aqueous solution is applied on a sheet of paper, applying this solution in a sizing solution at the stage of surface sizing of the paper making process.

The present invention will be further described in the following examples and tables. The examples are not intended to limit the scope of the invention set forth in the accompanying claims.

Examples

A. Drawing on a Dry Leaf/phase Sizing Surface

To illustrate the application of chemical substances at the stage of surface sizing paper production used two methods. One technique involves the fixation of a sample of dry paper sheet on the glass surface with adhesive tape, placement of the test solution on the upper Scotch line, and then rolling it with sticks for drawing. Another method involves the preparation of warm (60C) model sizing solution, usually from starch and in addition from other sizing components. A sample of the dry paper sheet is dipped in this solution for 10 seconds, and then passed through a press to remove excess solution.

After application of chemicals one of these methods test sheets were dried in a drum dryer (1 cycle, 100C) and resulted in a constant humidity of 50% and temperature is round 23C. Measured white, and then the leaves are put under "cool white" light on a rotating carousel at room temperature. In the tests used photoreactor LCZ-1 (LuzChem Research, St.Sauveur, QC, Canada). The samples were again brought to the specified balance and measured the white (whiteness R457, yellow E, Elrepho instrument-300, Datacolor International, Charlotte, NC).

Dosage in the above table were calculated in terms of wt.% A.S. mass and the product containing 40% active thiocyanates. To interpret these tables, you must use the following explication: Ged - initial white, YeO - initial-yellow, WH - white after lighting, Yel - yellowing after lighting, loss of white BrLoss=BrO-Brl, inhibition %lnh=100*[rLoss (control) - rLoss (sample)]/rLoss (control).

The experiments conducted using the first technique, illustrated in Tables 1 through 4, and the experiments conducted using the second method, illustrated in Tables 5 through 9.

Industrial commercial product ("benchmark product) to reduce fotopoulou, synergistic blend "Benzotriazol" (2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol, UV absorber) and 4-HydroxyTempo" (4-hydroxy-2,2,6,6-tetramethylpiperidinyloxy), a free radical compared with the application of an aqueous solution containing salt titanoboa acid.

Table 1
Bleached with hydrogen peroxide DMS (Midwest)
ChemicalsGedYeOBrlYelBrLoss%lnh
0.1% Benzotriazol+0.1% of 4-HydroxyTEMPO76,913,2575,1214,091,8439
The thiocyanate sodium 0,1%77,6212,5775,5813,612,0432
The thiocyanate sodium 0,2%77,3512,8475,6513,691,7144
Control77,6712,7274,6614,173,01

Table is CA 1 shows that at the same dosage the use of sodium thiocyanate works as a commercial product. Moreover, the thiocyanate gives the best initial whiteness and white samples after light is higher than that of the commercial product, even at a lower dosage.

Table 2
Bleached with hydrogen peroxide DMS (Midwest)
ChemicalsGedYeOBrlYelBrLoss%lnh
The thiocyanate sodium 0,1%74,7913,6373,8814,910,9136
The thiocyanate of calcium 0,2%74,8413,7473,8615,060,9832

Table 2 shows that the impact of thiocyanates not significantly depends on the cation.

Table 3
Bleached with hydrogen peroxide TSR (Northern Europe)
ChemicalsGedYeOBrlYelBrLoss%lnh
0.1% Benzotriazol+0.1% of 4-HydroxyTEMPO66,5of 21.263,2422,563,2320
The thiocyanate sodium 0,2%66,72163,5722,453,1522
The thiocyanate is sodium 0,1%66,8of 21.263,222,133,6210
DMFC * 0,1%+sodium thiocyanate 0,2%67,520,564,6221,342,8529
The thiocyanate is guanidine 0,1% 65,222,462,6223,362,6235
The guanidine thiocyanate 0,05%65,322,362,2323,383,0325
Control67,220,663,1322,524,04
*40%, neutralized to pH 6.

Table 3 shows that the impact of thiocyanates can be improved, if chemical substances combined with a chelating agent (for example, DMFC) in a single composition. The use of organic cations does not reduce the protective properties but in some cases (not always) can lead to a reduction of the initial white (this may be compensated by other means).

Table 4
Bleached with hydrogen peroxide TSR (Midwest)
The chemical is such substances GedYeOBrlYelBrLoss%lnh
0.1% Benzotriazol+0.1% of 4-HydroxyTEMPO66,539,5865.42 per13,261,1143
The thiocyanate sodium 0,1%66,689,6665,9213,140,7661
The thiocyanate sodium 0,2%66,489,7165,9313,030,5572

Table 4 shows that in the case of relatively low lighting effect save white can vary significantly, exceeding the effects of current chemical processes used in industry.

Table 5
The use of immersion in 6% starch bleached with hydrogen peroxide TSR (Central To the Nada)
ChemicalsGedYeOBrlYelBrLoss%lnh
The thiocyanate sodium 0,2%75,9013,9074,1414,511,7640
The thiocyanate sodium 0,1%75,8613,2474,0914,411,7839
The ammonium thiocyanate 0,2%76,612,7175,3213,671,2856
The ammonium thiocyanate 0,1%76,4212,7974,7013,951,7242
Di-n-butylphthalate 0,2%76,9012,7274,34of 14.282,5513

Table 5 shows that the ammonium thiocyanate more effective than sodium thiocyanate in this example. When used thiocyanat ammonium, greater initial whiteness and protection fotopoulou. For comparison, data are presented for the well-known protector of the type of UV setpagetitle.

22
Table 6
The use of immersion in 6% starch bleached with hydrogen peroxide TMDM (Central Canada)
ChemicalsGedBrlBrLoss%lnh 1
0,2% optical Brightenereyed at 79.1476,043,37
0.2% optical Brightener+0.1% ammonium thiocyanate79,4476,822,62
0,2% optical Brightener+0.2% ammonium thiocyanate79,8977,60to 2.2932

Table 6 shows that the proposed chemical treatment is also effective in the presence of optical Brightener. Optical Brightener in this table represents a stilbene fluorescent whitening agent, Tinopal ABP-A (Ciba Specialty, Tarrytown, NY).

Table 7
The use of immersion in 6% starch bleached with hydrogen peroxide TMDM (Central Canada); fotomodellen
ChemicalsGedYeOBrlYelBrLoss%lnh
Only the starch75,5513,3772,1715,453,37
The ammonium thiocyanate 0,1%+add*0,05%75,6613,08 73,28of 14.572,3530
The thiocyanate sodium 0,1%+TPC*0,05%75,6912,9573,5114,302,1835
The ammonium thiocyanate 0,1%+DMFC*0,05%75,5113,0473,3514,412,1636
* 40%, neutralized to run.

Table 7 shows an example of a combination of ammonium thiocyanate with different chelating agents.

Table 8
The use of wetting at 6% starch compounds from bleached with hydrogen peroxide DMS (Midwest) and bleached Kraft (Midwest), coniferous DMS
ChemicalsGedYeOBrlYelBrLoss%lnh
100%DMS 74,1114,0372,1516,171,96
90% Kraft/10% DMS79,918,6279,30of 10.050,61
80% Kraft/20% DMS79,269,2677,5611,431,70
70% Kraft/30% DMS78,57to 9.9176,6912,271,88
Thiocyanate sodium 0,1%+TPC*0,01% (100% DMS)sampled at 74.2513,7973,1315,121,1243
The thiocyanate sodium 0,1%+TPC*0,01% (90% Kraft/10% DMS)79,93of 8.3779,809,44 75
The thiocyanate sodium 0,1%+TPC*0,01% (80% Kraft/20% DMS)79,399,1078,8010,380,5965
The thiocyanate sodium 0,1%+TPC*0,01% (70% Kraft/30% DMS)75,769,7877,6011,341,1635
The thiocyanate sodium 0,2%+TPC*0,01% (80% Kraft/20% DMS)79,358,9978,8710,420,4872
The ammonium thiocyanate 0,2%+TPC*0,01% (70% Kraft/30% DMS)78,759,8177,8611,100,8950

Table 8 shows that the thiocyanate increases the stability fotopoulou Kraft mechanical structures, allowing, thus, less expensive formulations that contain more mechanical wood pulp, preserving properties over dorogostoyaschih compositions with higher content of Kraft.

Table 9
The use of wetting in 3% starch bleached with hydrogen peroxide TMDM (Midwest)
The chemical compositionGedYeOBrlYelBrLoss%lnh
0.1% benzotriazol79,1712,1376,4413,33to 2.6714
0.2% benzotriazol78,8212,5176,3213,442,5021
0.1 ammonium thiocyanate79,42to 11.5677,04was 12.752,3825
0.1%of the UV filter+0.1% ammonium thiocyanate79,2011,6877,27 12,601,9339
0.1% of the UV filter+0.1% ammonium thiocyanate79,2711,7677,5712,461,7046
0.2% ammonium thiocyanate79,49to 11.3177,57to 12.521,9240
0.1% of the UV filter+0.2% ammonium thiocyanate79,5211,41the sideways range between 77.9012,151,6249
0,2% UV filter+0.2% ammonium thiocyanate79,3711,4878,1012,121,2760
Control79,2911,7476,1213,553,16

Table 9 shows that the combination of thiocyanates with UV (the veto)-absorbers leads to a significant increase sewn white from fotopoulou.

Century, Drawing on the wet sheet

To illustrate the application of chemical substances on the wet sheet of the paper making process was used one technique (the use of the sheet with the wet end of the machine). This method includes fixing a wet sheet after casting, pressed (the concentration of 30-40%), but still not past the drum drier, on the glass surface with adhesive tape, placing the liquid to be tested on the upper Scotch line, and then rolling it with sticks for drawing.

After application of the chemical(s) by this method subjects the sheets were dried on a drum dryer (1 cycle, 100C) and resulted in a constant humidity of 50% and temperature 23C. was Measured whiteness, and then leaves covered "cool white" light on a rotating carousel at room temperature. In the experiments used photoreactor LCZ-1 (LuzChem Research, St.Sauveur, QC, Canada). The samples were again brought to the specified balance and measured the white (whiteness R457, yellow E, Elrepho instrument-300, Datacolor International, Charlotte, NC).

Doses in the following tables were calculated on the basis of A.S. mass and the product containing 40% active thiocyanates. To interpret these tables, you must use the following explication: Ged - initial white, YeO - initial yellowness, Brl - white after lighting, Yel - yellowing after lighting, loss of white BrLoss=BrO-Brl, ing the repression %lnh=100*[rLoss (control) - BrLoss (orsec)]/BrLoss (control).

Experiments performed using this technique, illustrated in Tables 10 and 11. Tables 10 and 11 show examples of two thiocyanates, put on a damp sheet to the dryer. In both cases, the observed protection of whiteness.

Table 10
Bleached with hydrogen peroxide TMDM (Central Canada)
ChemicalsGedYeOUseBrlYelBrLoss%lnh
The ammonium thiocyanate 0,1%75,7013,150,0373,0114,992,6917
The ammonium thiocyanate 0,2%74,78was 12.750,1173,7014,392,0836
Control75,67/td> of 13.0572,4315,383,24

Table 11
Bleached with hydrogen peroxide TMDM (Central Canada]
ChemicalsGedBrlBrLoss
Control76,672,34,3
The thiocyanate sodium 0,2%75,772,63,1
The thiocyanate of calcium 0,1%76,172,93,2

1. A method of reducing speed fotopoulou paper containing mechanical wood pulp, comprising coating the surface of a sheet of paper in the papermaking process an aqueous solution containing an effective amount of one or more salts titanoboa acid.

2. The method according to claim 1, in which the specified effective amount of salt is from 0.1 to 5 wt.% from the absolutely dry weight based on the 40% active solids.

3. The method according to claim 1, in which the interval specified pH of the solution is from 3 to 9, preferably from 6 to 7.

4. The method according to claim 1, in which the cations of these salts are selected from the group consisting of organic cations and inorganic cations.

5. The method according to claim 1, wherein said aqueous solution is applied on the paper sheet by applying a specified aqueous solution of a sizing solution under sizing of the surface specified in the papermaking process.

6. The method according to claim 1, wherein said aqueous solution is applied to the paper sheet by applying a specified aqueous solution to the pressing area specified papermaking process or after it.

7. The method according to claim 1, wherein said aqueous solution is applied to the paper sheet by applying a specified aqueous solution on the surface of the partially dewatered sheet in the papermaking process before he gets on the first clothes dryer.

8. The method according to claim 1, in which these salts are selected from the group consisting of inorganic thiocyanates, sodium thiocyanate, potassium thiocyanate, ammonium thiocyanate and calcium thiocyanate.

9. The method according to claim 1, additionally comprising adding individually or in a mixture with the specified aqueous solution an effective amount of chemicals selected from the group consisting of chelating agents, optical is their bleachers, fluorescent dyes, UV absorbers and combinations thereof.

10. The method according to claim 9, in which the specified effective amount of a chemical substance is from 0.01 to 5 wt.% from the absolutely dry weight based on the 40% active solids, preferably from 0.05 to 1.0 wt.% from the absolutely dry weight based on the 40% active solids.

11. The method according to claim 9, in which these UV absorbers are selected from the group consisting of benzotriazole, benzophenone, inorganic acids, organic particles and latex particles.

12. The method according to claim 9, in which these chelating agents are selected from the group consisting of ethylenediaminetetraacetic acid (edtc), etilenditiodiuksusnoi acid (DTPC) and diethylenetriaminepenta(methylphosphonic) acid (DMFC).

13. The method according to claim 9, in which these optical brighteners are selected from the group consisting of substituted, stilbene-, Tetra - and hexachloro acids, creatinineclearance acids, dicyano-1,4-bis-stilbestrol, bisbenzimidazole, bis(creatininemia)stilbene, molten sulfonated polyaromatic (multi-core) compounds, and distilbene.

14. The method according to claim 9, wherein said aqueous solution is mixed with the specified chelating agent in the ratio of from 1:100 to 100:1 based on active solids.

15. The method according to claim 9, in which is shown an aqueous solution is mixed with the specified UV absorber in the ratio from 1:100 to 100:1 based on active solids.

16. The method according to claim 1, wherein said aqueous solution is from about 10 to 60% aqueous solution of active material including sodium thiocyanate or ammonium thiocyanate, or a mixture of these sodium thiocyanate or ammonium thiocyanate with a chelating agent selected from the group consisting of add, DTPC and DMFC in the ratio from about 1:100 to 100:1.

17. The method according to claim 1, wherein said aqueous solution is applied to the wet paper sheet or on a dry sheet of paper.



 

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FIELD: organic chemistry, paper industry.

SUBSTANCE: invention relates to compositions used for coating paper covers. Invention describes a composition for coating paper cover comprising whitening pigment comprising: (a) product of melamine formaldehyde or phenol-formaldehyde polycondensation, and (b) water-soluble fluorescent whitening agent of the formula:

wherein R1 and R2 represent independently of one another -OH, -Cl, -NH2, -O-(C1-C4)-alkyl, -O-aryl, -NH-(C1-C4)-alkyl, -N-(C1-C4-alkyl)2, -N-(C1-C4)-alkyl-(C1-C4-hydroxyalkyl)- -N-(C1-C4-hydroxyalkyl)2 or -NH-aryl, for example, anilino-, anilinemono- or disulfonic acid or aniline sulfone amide, morpholino-, -S-(C1-C4)-alkyl(aryl) or radical of amino acid, for example, aspartic acid or iminoacetic acid that is replaced with radical in amino-group; M means hydrogen, sodium, potassium, calcium, magnesium atom or ammonium, mono-, di-, tri- or tetra-(C1-C4)-alkylammonium, mono-, di- or tri-(C1-C4)-hydroxyalkylammonium, or ammonium di- or tri-substituted with a mixture of (C1-C4)-alkyl and (C1-C4)-hydroxyalkyl groups. Covers prepared on coating paper elicit high photostability and enhanced whiteness degree.

EFFECT: improved method for preparing, improved properties of covers.

7 cl, 1 tbl, 3 ex

FIELD: paper industry.

SUBSTANCE: method is intended to impart dirt and/or moisture resistance to porous substrate for protected documents, and also relates to dirt and/or moisture resistant protected document. Method includes application of dirt and/or moisture resistant compound onto opposite surfaces of porous substrate having porosity of approximately 20-100 millilitres per minutes and its impression into pores of substrate. At the same time compound penetrates and spreads at least in part of substrate thickness, then excess compound is removed from opposite surfaces of substrate. Coating press is used to impress dirt and/or moisture resistant compound into pores of substrate.

EFFECT: specified compounds applied by suggested method do not darken optically variable effects generated by non-porous film structures on the basis of microlenses, which may be used on or inside these protected documents, and thin layers of fibres applied and this introduced into parts of protective devices in protected documents containing windows with dirt and/or moisture resistant properties according to the present invention, demonstrate improved durability.

22 cl, 1 ex

FIELD: soft wares, paper.

SUBSTANCE: invention concerns polymerous sheet perceiving thermally embossed image, on which with help of pigments or inks heat transmission it is capable to record an image with high contrast and definition. Image-receiving sheet for thermal image transfer contains lamellar basis with perceiving embossing image resinous layer. Current layer is coated by aquatic compound, which includes at least one water-dispersible resin on the basis of aliphatic (polyether)-polyurethane and at least one water-dispersible resin on the basis of aliphatic (polyester)-polyurethane or resin water dispersion on the basis of aliphatic (polyether)-polyurethane, silicon dioxide dispersion and wax anionic aqueous emulsion, and also aquatic coupling agent. Proposed invention provides receiving of perceiving layer with aquatic compounds usage, with image formation of high contrast range and storage stability.

EFFECT: receiving of perceiving layer with aquatic compounds usage, with image formation of high contrast range and storage stability.

20 cl, 1 dwg, 2 tbl, 2 ex

FIELD: chemical industry; methods of production of the solid carriers on the basis of chitosan.

SUBSTANCE: the invention is pertaining to production of the solid carrier on the basis of the organic and-or inorganic fibers used for production the material with barrier properties and to the method of its production. The technical result of the invention is production of the solid carrier coated with chitosan in the amount from 6 g/m2 on the dry residue by the method, in which the deposition is conducted during the limited number of the stages. The solid carrier on the basis of the organic and-or inorganic fibers used for production of the material with barrier properties is coated at least on its one side with the layer on the basis of chitosan. At that the layer is produced as a result of deposition on the carrier of the coating made out of the acid water solution containing the hydrolyzed chitosan, the average molecular mass of which makes less than 130 000 g/ mole, which concentration makes the value laying in the interval between 6 and 30 mass %, in quantity at least of 6 g/m2 for the solid residue. Such solid carrier may be used for production of the foodstuffs packages.

EFFECT: the invention ensures production of the solid carrier coated with chitosan in the amount from 6 g/m2 on the dry residue by the method, in which the deposition is conducted during the limited number of the stages.

13 cl, 4 ex, 3 tbl, 4 dwg

The invention relates to 2-oxetanone sizing agents, their preparation and application for paper sizing

The invention relates to the production of aqueous compositions of synthetic sizing agents that can be used in the manufacture of sized paper and similar products of cellulose fibers
Finishing agent // 2160805
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