Anti-fake coated cigarette card paper and its production process

Abstract

The application belongs to the technical field of papermaking, and particularly relates to a domestic fiber anti-fake coated cigarette card paper and a production process thereof. The domestic fiber anti-fake coated cigarette card paper comprises a base paper layer, a coating layer and a back adhesive layer. The base paper comprises a surface layer, a core layer and a bottom layer. The anti-fake domestic fiber accounts for 4-6% of the surface layer, 1-3% of the core layer and 6-9% of the bottom layer. The coating layer is coated on the surface layer and is divided into three layers, i.e., a pre-coating layer, a middle coating layer and a surface coating layer. The back adhesive layer is coated on the bottom layer. The application adds the anti-fake domestic fiber with different proportions in three layers to form a unique texture on the paper plane. The three-dimensional fiber texture with different levels and different brightness can be observed through light. The anti-fake fiber on the surface layer of the paper surface is greater than or equal to 50 per 55*22 mm, and the anti-fake fiber on the bottom layer is greater than or equal to 140 per 55*22 mm. The prepared coated cigarette card paper can be effectively distinguished from ordinary white card paper and has the anti-fake function.

Description

Technical Field

[0001] This invention belongs to the field of papermaking technology, specifically relating to fiber-coated anti-counterfeiting cigarette paper and its production process. Background Technology

[0002] Currently, cigarette packs and cartons primarily use coated white cardboard for packaging, with anti-counterfeiting technologies such as barcodes and printing security features applied to the outer surface. However, with the continuous development of new technologies, including advanced intelligent computer technology and high-precision digital printing, existing anti-counterfeiting technologies on the outer surface of the packaging are becoming increasingly ineffective and susceptible to counterfeiting, impacting the market. Since the packaging substrate currently used in the market is generally ordinary coated white cardboard, implementing anti-counterfeiting measures at the source paper level is both easier to differentiate and more convenient to implement.

[0003] Most anti-counterfeiting packaging papers on the market currently have poor anti-counterfeiting effects and cause serious pollution during the production process. Patent CN103790069A discloses an anti-counterfeiting cigarette cardboard that uses a mixture of unbleached pulp and bleached chemical wood pulp. Because unbleached pulp has its unique color, mixing it with bleached chemical wood pulp can change the color, thus giving the cardboard a certain color at the bottom. By adjusting the weight percentage of unbleached pulp and bleached chemical wood pulp, multiple colors can be obtained, resulting in different colored cardboards to achieve an anti-counterfeiting effect. However, color-based anti-counterfeiting is relatively easy to counterfeit, and the color difference produced by adjusting the weight percentage of unbleached pulp and bleached chemical wood pulp is not significant, making it difficult to distinguish genuine from counterfeit with the naked eye without using a color card. Patent CN1734016A discloses a black cardboard and its production method. Both the base paper and the back coating layer are dyed with a large amount of black dye. While this product achieves preliminary anti-counterfeiting through color differentiation, the dyeing process generates very difficult-to-treat wastewater, which is detrimental to environmental protection requirements. Furthermore, the paper itself retains a large amount of azo dyes and other chemicals, easily leading to excessive levels of volatile organic compounds (VOCs) and heavy metals. Patent CN103321096A discloses a coated white cardboard and its production process. The base paper of this product only has undyed fibers distributed in the bottom layer, resulting in lower anti-counterfeiting effectiveness. Moreover, after printing and boxing, the anti-counterfeiting bottom layer is inside the box, making it difficult to distinguish genuine from counterfeit products promptly and accurately. Therefore, providing a base paper material with higher anti-counterfeiting properties and easier direct differentiation is a problem that needs to be solved. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a fiber-coated anti-counterfeiting cigarette card that has high anti-counterfeiting properties, gloss, and a smooth surface.

[0005] This invention also provides a production process for anti-counterfeiting coated cigarette paper made of this fiber, which is simple, easy to implement, and suitable for large-scale production.

[0006] The anti-counterfeiting coated cigarette cardboard of the present invention includes a base paper layer, a coating layer, and an adhesive backing layer. The base paper includes a surface layer, a core layer, and a bottom layer. The surface layer contains 4%-6% anti-counterfeiting natural-colored fibers, the core layer contains 1%-3% anti-counterfeiting natural-colored fibers, and the bottom layer contains 6%-9% anti-counterfeiting natural-colored fibers. The coating layer is applied over the surface layer and consists of three layers from the inside out: a pre-coating, a middle coating, and a top coating. The adhesive backing layer is applied over the bottom layer.

[0007] The surface layer slurry comprises the following components by mass fraction:

[0008] Bleached hardwood sulfate pulp 77%-83%;

[0009] Bleached coniferous sulfate pulp 11%-19%;

[0010] Natural fiber content: 4%-6%.

[0011] The slurry of the core layer comprises the following components by mass fraction:

[0012]

[0013] The underlying slurry comprises the following components by mass fraction:

[0014] Bleached hardwood sulfate pulp 60%-70%;

[0015] Bleached coniferous sulfate pulp 21%-27%;

[0016] Natural fiber content: 6%-9%.

[0017] The application rates of the pre-coat, intermediate coat, and topcoat are 8.5-10.5 g / m², respectively. 2 8.5-10.5g / m 2 8-10g / m 2 The pre-coat and intermediate coat coatings comprise the following components in parts by weight:

[0018]

[0019] The topcoat coating comprises the following components in parts by weight:

[0020]

[0021]

[0022] The amount of adhesive applied to the backing layer is 0.5-1.5 g / m². 2 .

[0023] The adhesive layer is made by cooking and enzymatically hydrolyzing cassava starch and then diluting it to a solid content of 11-14%.

[0024] The production process of the anti-counterfeiting coated cigarette cardboard of this invention includes the following steps: bleached hardwood sulfate pulp, bleached softwood sulfate pulp, and unbleached fiber are mixed and fed according to the raw material ratio. The pulp is then broken down in a pulper, refined in a refiner, and mixed in a mixing tank according to the process ratio before entering the paper machine pulp tank. Simultaneously, 5-15 kg / t of dry strength agent is added. The pulp is then purified by a conical desander to remove heavy impurities, and pumped by a flushing pump to a pressure screen before the machine for further screening to remove light impurities. Finally, 0.5 kg / t of aluminum sulfate solution is added before the flushing pump. -50kg / t of cationic rosin gum, 0-15kg / t of talc filler, and 50-80kg / t of talc filler are used to form a three-layer paper machine. The face, core, and bottom layers are each distributed with a certain proportion of natural-colored fibers. During the forming process, starch (concentration 4.5-6.0%) is sprayed between the face and core layers and between the core and bottom layers. After compounding and pressing, a wet paper web with a dryness of 40-45% is obtained. This wet paper web is then pre-dried (drying temperature 92-102℃) and surface sizing is applied (sizing amount on the front side 2.0±0.5g / m). 2 Backside adhesive application rate: 1.5 ± 0.5 g / m 2 After drying (drying temperature 92-102℃), the base paper is obtained. It then undergoes hard calendering (calendering pressure 35-55kN / m, calendering temperature 180±20℃), pre-coating, intermediate coating, top coating, backing adhesive, and soft calendering (calendering pressure 35-55kN / m, calendering temperature 180±20℃) before entering the winding section for winding, rewinding, cutting, and packaging into finished products. Its technical specifications are: basis weight 220±3g / m³. 2 Thickness 295±7μm, front PPS roughness ≤1.1μm, front smoothness ≥800S, moisture 6.5±0.5%, front IGT ≥1.1m / s, front gloss 50.0±5.0%.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] (1) By adding three layers of natural-colored fibers in different proportions, the present invention not only forms a unique texture on the paper surface, but also shows three-dimensional fiber textures with different levels and different brightness when viewed through light. The surface layer of the paper has ≥50 anti-counterfeiting fibers per 55*22mm, and the bottom layer has ≥140 anti-counterfeiting fibers per 55*22mm. This makes the coated cigarette card paper obtained by the present invention effectively distinguishable from ordinary white card paper and has a unique anti-counterfeiting function.

[0027] (2) The backing is coated with an adhesive layer, which further improves the flatness of the back. At the same time, the stretching of the paper surface by the adhesive is more conducive to the adjustment of paper warping during subsequent printing and die-cutting.

[0028] (3) The natural fibers in the three layers do not require chemical treatment, thus avoiding the environmental impact of chemical agents in the bleaching process, which is both environmentally friendly and reduces costs.

[0029] (4) A certain proportion of kaolin was added to the coating, which improved the rheological properties of the coating, enhanced the gloss and surface properties of the coating, and the three-layer coating effectively reduced the surface roughness and improved the printability of the paper. Detailed Implementation

[0030] The present invention will be further described below with reference to the embodiments, but the scope of protection of the present invention is not limited thereto.

[0031] Unless otherwise specified, all raw materials used in the examples were commercially available.

[0032] Example 1

[0033] The production process of the fiber-coated anti-counterfeiting cigarette cardboard includes the following steps:

[0034] 1. Preparation:

[0035] (1) Preparation of sprayed starch

[0036] 350 kg of cassava starch was fed into a dissolving tank through a feeding funnel. At the same time, 2850 kg of water was added to the dissolving tank. The mixture was thoroughly diluted and stirred to prepare a 11% concentration spray starch solution. The solution was then diluted again with secondary dilution water to prepare a 4.5% concentration solution for later use.

[0037] (2) Preparation of talc filler

[0038] 1200 kg of talc powder is fed into a dissolving tank through a feeding funnel. At the same time, 4500 kg of water is added to the dissolving tank. The mixture is thoroughly diluted and stirred to prepare a 21% talc powder solution. The solution is then diluted again with secondary dilution water to prepare a 10% solution for later use.

[0039] (3) Preparation of aluminum sulfate solution

[0040] Dilute the aluminum sulfate stock solution (Boshan Ruijite food-grade aluminum sulfate with Al2O3 content ≥7.5%) with water 3 times and set aside.

[0041] (4) Preparation of cationic rosin gum solution

[0042] Dilute the food-grade cationic rosin collagen solution (Shanghai SOLENIS Hi-phase 1178 model) 15 times with water and set aside.

[0043] (5) Preparation of sizing starch and backing starch

[0044] 250 kg of raw cassava starch was fed into a dissolving tank through a feeding funnel. At the same time, 550 kg of water was added to the dissolving tank, and the mixture was thoroughly diluted and stirred to prepare a starch solution with a concentration of 31%. Amylase was added to the starch solution, and the solution was then heated to 80°C by steam for high-temperature enzymatic conversion. After the enzyme conversion, it was heated to 130°C by steam for high-temperature inactivation. Finally, the solution was diluted a second time with warm water to prepare a 13% solution for later use.

[0045] (6) Preparation of pre-coat and intermediate coat coatings:

[0046] According to the coating component ratio, 100 parts calcium carbonate, 14 parts styrene-butadiene latex, 0.4 parts carboxymethyl cellulose (purchased from Hubei Daya CMC), 0.12 parts NaOH, 0.15 parts dispersant (purchased from Changshu Polymer ZH-250), 0.01 parts bactericide (purchased from Emerson AmiCide BX 9058), 0.08 parts defoamer (purchased from Emerson AmiDefoam 5873), 0.5 parts water-resistant agent (purchased from Kesike KSK 386-503), and 0.25 parts lubricant (purchased from Jiuzhou Bio NCC MS-268) were added in batches to a dispersion tank, and water was added simultaneously for dilution, to obtain a pre-coat and intermediate coat coating with a solid content of 68.5%, which was then set aside for use.

[0047] (7) Preparation of the topcoat coating:

[0048] According to the coating component ratio, 75 parts calcium carbonate, 14.5 parts styrene-butadiene latex, 25 parts kaolin, 0.3 parts carboxymethyl cellulose, 0.12 parts NaOH, 0.15 parts dispersant (purchased from Changshu Polymer ZH-250), 0.01 parts bactericide (purchased from Emerson AmiCide BX 9058), 0.08 parts defoamer (purchased from Emerson AmiDefoam 5873), 0.5 parts water-resistant agent (purchased from Kesike KSK 386-503), and 0.25 parts lubricant (purchased from Kyushu Bio NCC MS-268) were added in batches to a dispersion tank, and water was added simultaneously for dilution to obtain a topcoat with a solid content of 65%, which was then set aside for later use.

[0049] 2. Pulping:

[0050] (1) Preparation of No. 1 pulp line:

[0051] Bleached softwood sulfate pulp (100% Silver Star NBKP), bleached hardwood sulfate pulp (100% Eucalyptus LBKP), and unbleached fiber (100% Platinum pulp, using unbleached Kraft Pulp Grade 670, produced from Douglas fir wood native to the Pacific Northwest, known for its long fibers and thick walls, suitable for producing high-strength paper) were added to the feed conveyor in a ratio of 8:1:3. To ensure uniform mixing, the pulp was distributed in the following order: 1 bag of bleached hardwood sulfate pulp + 2 bags of unbleached fiber + 4 bags of bleached softwood sulfate pulp + 1 bag of unbleached fiber + 4 bags of bleached softwood sulfate pulp. After dispersion in a pulper, impurity removal in a desander, and refining in a refiner, a pulp concentrate of 3.5% and a freeness of 320 cfs, with a ratio of 8% LBKP + 25% Platinum pulp + 67% NBKP, was obtained for line #1.

[0052] (2) Preparation of No. 2 pulp line:

[0053] 100% bleached hardwood sulfate pulp (100% eucalyptus LBKP) is fed onto the feeding chain plate. After being dispersed by a pulper, removed by a slag remover, and refined by a pulper, pulp material for line #2 with a concentration of 4.3%, a freeness of 360 cfs, and a ratio of 100% LBKP is obtained.

[0054] (3) Preparation of No. 3 pulp line:

[0055] The chemimechanical pulp produced by the hydrogen peroxide bleaching method in the No. 3 pulp line is refined by a refiner to obtain pulp with a concentration of 4.0%, a freeness of 440 cfs, and a formulation of 100% APMP.

[0056] 3. Mixing and papermaking:

[0057] Using an automatic batching system, the slurries from slurry lines 1#, 2#, and 3# are mixed in the following proportions to produce a three-layer slurry: surface, core, and base layers.

[0058] Surface layer: 25% No. 1 pulp line + 75% No. 2 pulp line mixed, final ratio: 79% bleached hardwood sulfate pulp + 17% bleached softwood sulfate pulp + 4% unbleached fiber;

[0059] Core layer: 10% No. 1 pulp line + 5% No. 2 pulp line + 60% No. 3 pulp line + 25% waste paper. Final ratio: 7% bleached hardwood sulfate pulp + 6% bleached softwood sulfate pulp + 2% unbleached fiber pulp + 65% bleached chemimechanical pulp + 20% waste paper.

[0060] Bottom layer: 35% No. 1 pulp line + 65% No. 2 pulp line mixed, final ratio: 70% bleached hardwood sulfate pulp + 24% bleached softwood sulfate pulp + 6% unbleached fiber;

[0061] The mixed pulp is pumped to the paper machine tank and mixed evenly. 5 kg / t and 10 kg / t of dry strength agent (Axchem KWT-201A cationic polyacrylamide, 20% concentration) are added to the core and bottom layers of the paper machine tank, respectively. The pulp is then sequentially transferred to a desander for desanding and a flushing pump for dilution. Aluminum sulfate solution and cationic rosin are added to the top and core flushing pumps, while aluminum sulfate solution, cationic rosin, and talc filler are added to the bottom flushing pump. The amounts of the prepared aluminum sulfate solution added are: 0 kg / t for the top layer, 50 kg / t for the core layer, and 6 kg / t for the bottom layer. The amounts of the prepared cationic rosin solution added are: 0 kg / t for the top layer, 3 kg / t for the core layer, and 8 kg / t for the bottom layer. The amount of talc filler added to the bottom layer is 80 kg / t. The pulp after flushing is purified by a pressure screen. Before pressure screen purification (at the pressure screen inlet), a retention and filter aid (Axchem AXFLOC AF) is added. The pulp (model 904PG) has a concentration of 0.20%, with an addition amount of 300 ppm for the top layer, 300 ppm for the core layer, and 350 ppm for the bottom layer. After purification by a pressure screen, the purified pulp is transported to the headbox for papermaking. At the same time, the concentration on the wire is controlled at 0.4% for both the top and bottom layers and 1.1% for the core layer. Finally, the paper is wire-formed. During the wire-forming stage, starch is sprayed between the paper layers to promote paper bonding. The concentration of the sprayed starch is 4.5%, and the amount used is 1.5 kg per ton of paper. After pressing and dewatering, a wet paper web with a dryness of 43% is obtained.

[0062] The wet paper web is steam-dried in six pre-drying cylinders at a gradually increasing temperature of 64-95℃ to obtain a paper web with a dryness of 86%. This paper web is then surface-sized using a sizing machine at a sizing concentration of 13% and a sizing amount of 2.3 g / m² on the front side. 2 Backside adhesive application rate: 1.4g / m 2 After passing through three sets of drying cylinders, the paper then goes through a hard calender at a pressure of 35 kN / m and a temperature of 180℃. Following this, it undergoes four coating processes: front pre-coating, front intermediate coating, back adhesive coating, and front top coating, to finish the surface of the base paper. The front pre-coating is 9.5 g / m². 2 Top coat 8.5g / m 2 Topcoat 9.5g / m 2 Adhesive content: 0.67g / m 2 After coating, the paper is passed through a soft calender with a calendering pressure of 49kN / m and a calendering temperature of 190℃. Then, it is wound, rewound and slit to obtain the fiber-coated anti-counterfeiting cigarette card.

[0063] Comparative Example 1

[0064] Similar to Example 1, the difference is that the topcoat is removed and no natural-colored fibers are added.

[0065] Comparative Example 2

[0066] Similar to Example 1, the difference is that the backing adhesive has been removed and no natural-colored fibers have been added.

[0067] The table below compares the physical properties of the fiber-coated anti-counterfeiting cigarette paper prepared in the examples with those of Comparative Example 1, Comparative Example 2, and ordinary yellow-core cigarette paper:

[0068]

[0069]

Claims

1. A type of anti-counterfeiting coated cigarette card, characterized in that, The material comprises a base paper layer, a coating layer, and an adhesive layer. The base paper includes a surface layer, a core layer, and a bottom layer. The surface layer contains 4% natural anti-counterfeiting fiber, the core layer contains 1%-3% natural anti-counterfeiting fiber, and the bottom layer contains 6% natural anti-counterfeiting fiber. The coating layer is applied over the surface layer and consists of three layers from the inside out: a pre-coat, a middle coating, and a top coating. The adhesive layer is applied over the bottom layer. The surface layer slurry comprises the following components by mass fraction: Bleached hardwood sulfate pulp 77%-83%; Bleached softwood sulfate pulp 11%-19%; 4% natural fiber; The slurry of the core layer comprises the following components by mass fraction: 5%-15% bleached hardwood sulfate pulp; Bleached softwood sulfate pulp 0-10%; Paper wastage is 20%-35%; Natural fiber content: 1%-3%; Bleached chemimechanical pulp 50%-70%; The underlying slurry comprises the following components by mass fraction: Bleached hardwood sulfate pulp 60%-75%; Bleached softwood sulfate pulp 21%-27%; 6% natural fiber.

2. The anti-counterfeiting coated cigarette cardboard according to claim 1, characterized in that, The application rates of the pre-coat, intermediate coat, and topcoat are 8.5-10.5 g / m², respectively. 2 8.5-10.5g / m 2 8-10g / m 2 .

3. The anti-counterfeiting coated cigarette cardboard according to claim 1, characterized in that, The pre-coat and intermediate coat coatings comprise the following components in parts by weight: 100 parts of calcium carbonate; 13-15 parts latex; 0.3-0.5 parts of carboxymethyl cellulose; Dispersant 0.1-0.2 parts; Water-resistant agent 0.5-1.0 parts; Lubricant 0.2-0.4 parts; Defoamer 0.05-0.1 parts; 0.01-0.04 parts of bactericide; 0.1-0.15 parts of NaOH.

4. The anti-counterfeiting coated cigarette cardboard according to claim 1, characterized in that, The topcoat coating comprises the following components in parts by weight: 70-80 parts calcium carbonate; 20-30 parts of porcelain clay; 14-16 parts latex; 0.3-1.0 parts of carboxymethyl cellulose; Dispersant 0.1-0.15 parts; Water-resistant agent 0.5-1.0 parts; Lubricant 0.2-0.4 parts; Defoamer 0.05-0.1 parts; 0.01-0.04 parts of bactericide; 0.1-0.15 parts of NaOH.

5. The anti-counterfeiting coated cigarette cardboard according to claim 1, characterized in that, The amount of adhesive applied to the backing layer is 0.5-1.5 g / m². 2 .

6. The anti-counterfeiting coated cigarette cardboard according to claim 1, characterized in that, The adhesive layer is made by cooking and enzymatically hydrolyzing cassava starch and then diluting it to a solid content of 11-14%.

7. A production process for intrinsically fiber anti-counterfeiting coated cigarette cardboard according to any one of claims 1-6, characterized in that, Includes the following steps: Bleached hardwood sulfate pulp, bleached softwood sulfate pulp, and unbleached fiber are mixed and fed according to the raw material ratio. The pulp is then broken down in a pulper, refined in a refiner, and mixed in a mixing tank according to the process ratio before entering the paper machine pulp tank. At the same time, 5-15 kg / t of dry strength agent is added. The pulp is then purified by a conical separator to remove heavy impurities, and pumped to a pressure screen before the machine for further screening to remove light impurities. Before the flushing pump, 0-50 kg / t of aluminum sulfate solution and 0-15 kg / t of cationic rosin are added. g / t, talc filler 50-80kg / t, then formed on a three-layer stacked wire paper machine, with a certain proportion of natural-colored fibers distributed in the face, core and bottom layers. During the forming process, starch is sprayed between the face and core and between the core and bottom. After compounding and pressing, a wet paper web with a dryness of 40-45% is obtained. This wet paper web is then pre-dried, surface sizing and post-dried to obtain the base paper. After hard calendering, pre-coating, intermediate coating, surface coating, backing adhesive and soft calendering, it enters the winding section, where it is wound, rewound, cut and packaged into finished products.

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