Process for preparing water-resistant coated paper based on water-based acrylic resin coating

Abstract

The invention relates to the technical field of coated paper production, in particular to a process for preparing water-resistant coated paper based on a water-based acrylic resin coating. A ternary composite system composed of anionic polyacrylamide, cationic starch and cationic polyacrylamide can increase more flocculation opportunities to facilitate retention and rapid water filtration, the retention rate of fine fibers and filler is increased on the premise of ensuring that the coated paper has excellent uniformity, the retention rate in the whole process reaches 90% or above, and the retention rate of the fine fibers and filler reaches 90% or above. The white water pollution load is reduced, and the environment is protected; furthermore, the filling amount of the original filler is increased while the mechanical property of the coated paper is not influenced, and the production cost of the raw paper is reduced; in addition, the prepared water-resistant coated paper has excellent water resistance, mechanical property and antibacterial property, and the quality of the water-resistant coated paper is effectively guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of coated paper production, in particular to a process for preparing water-resistant coated paper based on water-based acrylic resin coating. Background Art

[0002] Coated paper is commonly known as coated paper. There are many types of coated paper that can be used for printing various color printed materials. Coating means to apply a thin layer of plastic in liquid or powder form on the surface of fabrics, paper, metal foil or plates for the purpose of corrosion protection, insulation, decoration, etc. It is one of the most commonly used paper types in cultural publishing, advertising design, printing and binding, and industrial and commercial industries. The main uses are: printing magazines, books and other publishing papers, and trademarks, packaging, product catalogs and other printing papers.

[0003] In the patent document with application number "CN201210570345.1" and name "coated paper", a coated paper is disclosed, which includes base paper and at least one coating formed on one or both sides of the base paper. The outermost coating of the coated paper is an antibacterial coating, which contains an antibacterial agent and a carrier, and the antibacterial agent is loaded on the carrier. Although the coated paper prepared by the above patent document has excellent antibacterial effect, its own water resistance is relatively poor, and its environmental pollution degree and production cost are also relatively large. Based on the above, the present invention provides a process for preparing water-resistant coated paper based on water-based acrylic resin coating! Summary of the invention

[0004] The purpose of the present invention is to provide a process for preparing water-resistant coated paper based on water-based acrylic resin coating, wherein the prepared coated paper has not only excellent water resistance but also good antibacterial performance; furthermore, the present invention increases the amount of base paper filler added without affecting the mechanical properties of the coated paper, thereby reducing the production cost of the base paper; in addition, under the premise of ensuring that the coated paper has excellent uniformity, the retention rate of fine fibers, fillers, etc. is increased, and the whole-process retention rate reaches more than 90%, thereby reducing the white water pollution load and protecting the environment.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A process for preparing water-resistant coated paper based on water-based acrylic resin coating comprises the following steps:

[0007] Step 1, alkaline hydrogen peroxide bleached poplar mechanical pulp APMP, bleached hardwood kraft pulp and bleached coniferous kraft pulp are mixed and stirred in a weight ratio of 1.5-2:8-18:1 to form a mixed absolute dry pulp, and then 12-18% of the modified filler, 0.5-1% of the composite nano powder, and 0.2-0.5% of the AKD neutral sizing agent are added to the obtained mixed absolute dry pulp, and the mixture is mixed and stirred to form a base paper absolute dry pulp, and then the base paper is made into a coated base paper after papermaking and pressing and dehydration;

[0008] Step 2: Use a blade to determine that the coating thickness is 30-80 μm, use a coating machine to apply the water-based acrylic resin coating on the surface of the coated base paper, dry it and flatten it after coating; then adjust the calender temperature to 55-65° C., and perform calendering treatment on it under the conditions of a pressure of 13-16 N / m and a rotation speed of 5-10 m / min;

[0009] Step 3: After calendering is completed, place the coated water-resistant coated paper in a constant temperature and humidity chamber and balance the moisture for 20 to 25 hours at a temperature of 25 to 30°C and a humidity of 50 to 60 RH. The final result is water-resistant coated paper prepared with water-based acrylic resin coating.

[0010] Furthermore, the preparation method of the modified filler is as follows: anionic polyacrylamide with a mass of 0.05-0.4wt% of the nano-calcium carbonate is added to a 20-30wt% nano-calcium carbonate aqueous suspension, and after uniform dispersion for 5-8 minutes, cationic polyacrylamide with a mass of 0.08-1.5% of the nano-calcium carbonate is added thereto, and after uniform dispersion for 5-8 minutes, cationic starch with a mass of 0.08-1.5% of the nano-calcium carbonate is added thereto, and mixed and stirred for 5-8 minutes to obtain the modified filler.

[0011] Furthermore, the composite nano powder is prepared by mixing nano zinc oxide and nano titanium dioxide in a mass ratio of 1:1 to 2.

[0012] Furthermore, the alkaline hydrogen peroxide bleached poplar mechanical pulp APMP is made from poplar fiber raw material using the PRC-APMP pulping process, and its whiteness is 75-78% ISO; the pulping concentration of bleached kraft coniferous pulp and bleached kraft broadleaf pulp is 3.5-4.5%, and the beating degrees are 40-45°SR and 35-40°SR respectively.

[0013] Furthermore, the water-based acrylic resin coating is prepared by mixing the following raw materials in parts by weight: 60 to 90 parts of acrylic emulsion, 6 to 10 parts of propylene glycol ether, 3 to 8 parts of nano titanium dioxide, 1.5 to 2.5 parts of dispersant, 0.6 to 1.0 parts of defoamer, 20 to 40 parts of filler, 4 to 6 parts of antibacterial agent, 3 to 5 parts of water repellent and 10 to 20 parts of deionized water.

[0014] Furthermore, the dispersant is selected from any one of Shenzhen Haichuan's 963S dispersant, American Hemmings' 9086 dispersant, German BYK-163 dispersant, and German BYK-108 dispersant.

[0015] Furthermore, the defoaming agent is selected from any one of Deqian 6500 defoaming agent, Haichuan E1 defoaming agent, and German BYK Chemical BYK-141 defoaming agent.

[0016] Furthermore, the filler is selected from any one of kaolin, talc, calcium carbonate and mica powder.

[0017] Furthermore, the antibacterial agent is selected from any one of 5-chloro-2-methyl-4-isothiazoline-3-one and 2-methyl-4-isothiazoline-3-one.

[0018] Furthermore, the preparation method of the water repellent is as follows: add 5-10% of hexadecyltriethoxysilane, 1.5-3.0% of acetic acid and deionized water with the same mass as the acetic acid to anhydrous ethanol respectively, mix and stir evenly, and then stir and react at a temperature of 40-60°C for 80-120 minutes; after the reaction is completed, add perfluorooctane with the same mass as the anhydrous ethanol to the obtained product components, and stir rapidly at a temperature of 30-40°C for 5-10 hours, and filter out the upper liquid after standing, and the final product is the water repellent.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention uses anionic polyacrylamide, cationic starch and cationic polyacrylamine to form a polyelectrolyte complex, and coats the complex on the surface of nano calcium carbonate, and then uses the flocculation principle to pre-flocculate the nano calcium carbonate coating, and the filler is added to the mixed pulp in the form of coated prepolymer for dehydration and formation. While not affecting the mechanical properties of the coated paper, the amount of the original filler is increased, and the production cost of the base paper is reduced. Furthermore, the ternary composite system composed of anionic polyacrylamide, cationic starch and cationic polyacrylamine can increase more flocculation opportunities, which is beneficial to retention and rapid water filtration. Under the premise of ensuring that the coated paper has excellent uniformity, the retention rate of fine fibers and fillers is increased, and the retention rate throughout the process reaches more than 90%, which reduces the pollution load of white water and protects the environment.

[0021] 2. The present invention applies water-based acrylic resin coating on the surface of the coated base paper, effectively ensuring its mechanical properties. Among them, the homemade water repellent can effectively improve the water resistance of the coated paper, and the use of the antibacterial agent can cooperate with the composite nanopowder to effectively enhance the antibacterial properties of the coated paper and effectively ensure its quality. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1

[0024] A process for preparing water-resistant coated paper based on water-based acrylic resin coating comprises the following steps:

[0025] Step 1, alkaline hydrogen peroxide bleached poplar mechanical pulp APMP, bleached hardwood kraft pulp and bleached coniferous kraft pulp are mixed and stirred in a weight ratio of 1.5:8:1 to form a mixed absolute dry pulp, and then 12% of the modified filler, 0.5% of the composite nano powder and 0.2% of the AKD neutral sizing agent are added to the obtained mixed absolute dry pulp, and the mixture is mixed and stirred to form a base paper absolute dry pulp, and then the base paper is made into coated base paper after papermaking and pressing and dehydration; wherein the alkaline hydrogen peroxide bleached poplar mechanical pulp APMP is made of poplar fiber raw material using the PRC-APMP pulping process, and its whiteness is 75% ISO; the beating concentration of the bleached kraft coniferous pulp and the bleached kraft hardwood pulp is 3.5%, and the beating degrees are 40°SR and 35°SR respectively;

[0026] Step 2: Use a blade to determine that the coating thickness is 30 μm, and use a coating machine to apply the water-based acrylic resin coating on the surface of the coated base paper, and then dry and flatten it after coating; then adjust the calender temperature to 55° C., and perform calendering treatment on it under the conditions of a pressure of 13 N / m and a rotation speed of 5 m / min;

[0027] Step 3: After calendering is completed, place the coated water-resistant coated paper in a constant temperature and humidity chamber and balance the moisture for 20 hours at a temperature of 25°C and a humidity of 50RH. The final result is water-resistant coated paper prepared with water-based acrylic resin coating.

[0028] The preparation method of the modified filler is as follows: add anionic polyacrylamide with a mass of 0.05wt% of the nano-calcium carbonate to a 20wt% nano-calcium carbonate aqueous suspension, uniformly disperse for 5 minutes, then add cationic polyacrylamide with a mass of 0.08% of the nano-calcium carbonate, uniformly disperse for 5 minutes, then add cationic starch with a mass of 0.08% of the nano-calcium carbonate, mix and stir for 5 minutes to obtain the modified filler.

[0029] The composite nano powder is prepared by mixing nano zinc oxide and nano titanium dioxide in equal quantities.

[0030] The water-based acrylic resin coating is prepared by mixing the following raw materials in parts by weight: 60 to 90 parts of acrylic emulsion, 6 parts of propylene glycol ether, 3 parts of nano titanium dioxide, 1.5 parts of Shenzhen Haichuan's 963S dispersant, 0.6 parts of Deqian 6500 defoaming agent, 20 parts of kaolin, 4 parts of 5-chloro-2-methyl-4-isothiazoline-3-one, 3 parts of water repellent and 10 parts of deionized water.

[0031] The preparation method of the water repellent is as follows: 5% of hexadecyltriethoxysilane by mass, 1.5% of acetic acid and deionized water by mass equal to that of the acetic acid are added to anhydrous ethanol respectively, mixed and stirred evenly, and then stirred and reacted at a temperature of 40°C for 80 minutes; after the reaction is completed, perfluorooctane by mass equal to that of anhydrous ethanol is added to the obtained product components, and rapidly stirred at a temperature of 30°C for 5 hours, and the upper liquid is filtered out after standing, and the final product is the water repellent.

[0032] Example 2

[0033] A process for preparing water-resistant coated paper based on water-based acrylic resin coating comprises the following steps:

[0034] Step 1, alkaline hydrogen peroxide bleached poplar mechanical pulp APMP, bleached hardwood kraft pulp and bleached coniferous kraft pulp are mixed and stirred in a weight ratio of 2:15:1 to form a mixed absolute dry pulp, and then 15% of the modified filler, 0.8% of the composite nano powder and 0.4% of the AKD neutral sizing agent are added to the obtained mixed absolute dry pulp, and the mixture is mixed and stirred to form a base paper absolute dry pulp, and then the base paper is made into coated base paper after papermaking and pressing and dehydration; wherein the alkaline hydrogen peroxide bleached poplar mechanical pulp APMP is made of poplar fiber raw material using the PRC-APMP pulping process, and its whiteness is 76% ISO; the beating concentration of the bleached kraft coniferous pulp and the bleached kraft hardwood pulp is 4.0%, and the beating degrees are 42°SR and 38°SR respectively;

[0035] Step 2: Use a blade to determine that the coating thickness is 50 μm, use a coating machine to apply the water-based acrylic resin coating on the surface of the coated base paper, dry it and flatten it after coating; then adjust the calender temperature to 60° C., and perform calendering treatment on it under the conditions of a pressure of 15 N / m and a rotation speed of 8 m / min;

[0036] Step 3: After calendering is completed, place the coated water-resistant coated paper in a constant temperature and humidity chamber and balance the moisture for 20 hours at a temperature of 25°C and a humidity of 55RH. The final result is water-resistant coated paper prepared with water-based acrylic resin coating.

[0037] The preparation method of the modified filler is as follows: add anionic polyacrylamide with a mass of 0.2wt% of the nano-calcium carbonate to a 25wt% nano-calcium carbonate aqueous suspension, uniformly disperse for 6 minutes, then add cationic polyacrylamide with a mass of 1.0% of the nano-calcium carbonate, uniformly disperse for 6 minutes, then add cationic starch with a mass of 1.2% of the nano-calcium carbonate, mix and stir for 6 minutes to obtain the modified filler.

[0038] The composite nano powder is prepared by mixing nano zinc oxide and nano titanium dioxide in a mass ratio of 1:1.5.

[0039] The water-based acrylic resin coating is prepared by mixing the following raw materials in parts by weight: 80 parts of acrylic emulsion, 8 parts of propylene glycol ether, 5 parts of nano titanium dioxide, 2.0 parts of Hemmings 9086 dispersant from the United States, 0.8 parts of Haichuan E1 defoaming agent, 30 parts of talc, 5 parts of 2-methyl-4-isothiazoline-3-one, 4 parts of water repellent and 15 parts of deionized water.

[0040] The preparation method of the water repellent is as follows: 8% of hexadecyltriethoxysilane by mass, 2.5% of acetic acid and deionized water by mass equal to that of the acetic acid are added to anhydrous ethanol respectively, the mixture is stirred evenly, and the mixture is stirred and reacted at a temperature of 50°C for 100 minutes; after the reaction is completed, perfluorooctane by mass equal to that of the anhydrous ethanol is added to the obtained product components, and the mixture is rapidly stirred at a temperature of 35°C for 8 hours, and the upper liquid is filtered out after standing, and the final product is the water repellent.

[0041] Example 3

[0042] A process for preparing water-resistant coated paper based on water-based acrylic resin coating comprises the following steps:

[0043] Step 1, alkaline hydrogen peroxide bleached poplar mechanical pulp APMP, bleached hardwood kraft pulp and bleached coniferous kraft pulp are mixed and stirred in a weight ratio of 2:18:1 to form a mixed absolute dry pulp, and then 18% of the modified filler, 1% of the composite nano powder and 0.5% of the AKD neutral sizing agent are added to the obtained mixed absolute dry pulp, and the mixture is mixed and stirred to form a base paper absolute dry pulp, and then the base paper is made into coated base paper after papermaking and pressing and dehydration; wherein the alkaline hydrogen peroxide bleached poplar mechanical pulp APMP is made of poplar fiber raw material using the PRC-APMP pulping process, and its whiteness is 78% ISO; the beating concentration of the bleached kraft coniferous pulp and the bleached kraft hardwood pulp is 4.5%, and the beating degrees are 45°SR and 40°SR respectively;

[0044] Step 2: Use a blade to determine that the coating thickness is 80 μm, use a coating machine to apply the water-based acrylic resin coating on the surface of the coated base paper, dry it and flatten it after coating; then adjust the calender temperature to 65° C., and perform calendering treatment on it under the conditions of a pressure of 16 N / m and a rotation speed of 10 m / min;

[0045] Step 3: After calendering is completed, place the coated water-resistant coated paper in a constant temperature and humidity chamber and balance the moisture for 25 hours at a temperature of 30°C and a humidity of 60RH. The final result is water-resistant coated paper prepared with water-based acrylic resin coating.

[0046] The preparation method of the modified filler is as follows: add anionic polyacrylamide with a mass of 0.4wt% of nano-calcium carbonate to a 30wt% nano-calcium carbonate aqueous suspension, uniformly disperse for 8 minutes, then add cationic polyacrylamide with a mass of 1.5% of nano-calcium carbonate, uniformly disperse for 8 minutes, then add cationic starch with a mass of 1.5% of nano-calcium carbonate, mix and stir for 8 minutes to obtain the modified filler.

[0047] The composite nano powder is prepared by mixing nano zinc oxide and nano titanium dioxide in a mass ratio of 1:2.

[0048] The water-based acrylic resin coating is prepared by mixing the following raw materials in parts by weight: 90 parts of acrylic emulsion, 10 parts of propylene glycol ether, 8 parts of nano titanium dioxide, 2.5 parts of BYK-163 dispersant from German BYK Chemical, 1.0 part of German BYK Chemical BYK-141 defoamer, 40 parts of calcium carbonate, 6 parts of 5-chloro-2-methyl-4-isothiazoline-3-one, 5 parts of water repellent and 20 parts of deionized water.

[0049] The preparation method of the water repellent is as follows: add 10% of hexadecyltriethoxysilane, 3.0% of acetic acid and deionized water of the same mass as the acetic acid to anhydrous ethanol respectively, mix and stir evenly, and then stir and react at 60°C for 120 minutes; after the reaction is completed, add perfluorooctane of the same mass as the anhydrous ethanol to the obtained product components, and stir rapidly for 10 hours at 40°C, and filter out the upper liquid after standing, and the final product is the water repellent.

[0050] Performance test: The relevant properties of the water-resistant coated paper samples provided in Examples 1 to 3 were tested respectively, and the obtained test data are recorded in the following table:

[0051]

[0052] Note: The contact angle values ​​in the table have been rounded off.

[0053] By comparing and analyzing the relevant data in the table, it can be known that the coated paper prepared by the present invention not only has excellent water resistance, but also has good antibacterial properties. Furthermore, the present invention increases the amount of base paper filler without affecting the mechanical properties of the coated paper, thereby reducing the production cost of the base paper. In addition, under the premise of ensuring that the coated paper has excellent uniformity, the retention rate of fine fibers, fillers, etc. is increased, and the retention rate throughout the process reaches more than 90%, which reduces the white water pollution load and protects the environment. This shows that the water-resistant coated paper and its production process provided by the present invention have a broader market prospect and are more suitable for promotion.

[0054] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0055] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A process for preparing water-resistant coated paper based on water-based acrylic resin coating, characterized in that: The steps include: Step 1, alkaline hydrogen peroxide bleached poplar mechanical pulp APMP, bleached hardwood kraft pulp and bleached coniferous kraft pulp are mixed and stirred in a weight ratio of 1.5-2:8-18:1 to form a mixed absolute dry pulp, and then 12-18% of the modified filler, 0.5-1% of the composite nano powder, and 0.2-0.5% of the AKD neutral sizing agent are added to the obtained mixed absolute dry pulp, and the mixture is mixed and stirred to form a base paper absolute dry pulp, and then the base paper is made into a coated base paper after papermaking and pressing and dehydration; Step 2: Use a blade to determine that the coating thickness is 30-80 μm, use a coating machine to apply the water-based acrylic resin coating on the surface of the coated base paper, dry it and flatten it after coating; then adjust the calender temperature to 55-65° C., and perform calendering treatment on it under the conditions of a pressure of 13-16 N / m and a rotation speed of 5-10 m / min; Step 3: After calendering is completed, place the coated water-resistant coated paper in a constant temperature and humidity chamber and balance the moisture for 20 to 25 hours at a temperature of 25 to 30°C and a humidity of 50 to 60 RH. The final result is water-resistant coated paper prepared with water-based acrylic resin coating.

2. A process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 1, characterized in that: The preparation method of the modified filler is as follows: anionic polyacrylamide with a mass of 0.05-0.4wt% of the nano-calcium carbonate is added to a 20-30wt% nano-calcium carbonate aqueous suspension, and after uniform dispersion for 5-8 minutes, cationic polyacrylamide with a mass of 0.08-1.5% of the nano-calcium carbonate is added thereto, and after uniform dispersion for 5-8 minutes, cationic starch with a mass of 0.08-1.5% of the nano-calcium carbonate is added thereto, and mixed and stirred for 5-8 minutes to obtain the modified filler.

3. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 1, characterized in that: The composite nanometer powder is prepared by mixing nanometer zinc oxide and nanometer titanium dioxide in a mass ratio of 1:1-2.

4. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 1, characterized in that: The alkaline hydrogen peroxide bleached poplar mechanical pulp APMP is made of poplar fiber raw material using the PRC-APMP pulping process, and its whiteness is 75-78% ISO; the beating concentration of bleached kraft coniferous wood pulp and bleached kraft broadleaf wood pulp is 3.5-4.5%, and the beating degrees are 40-45°SR and 35-40°SR respectively.

5. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 1, characterized in that: The water-based acrylic resin coating is prepared by mixing the following raw materials in parts by weight: 60 to 90 parts of acrylic emulsion, 6 to 10 parts of propylene glycol ether, 3 to 8 parts of nano titanium dioxide, 1.5 to 2.5 parts of dispersant, 0.6 to 1.0 parts of defoamer, 20 to 40 parts of filler, 4 to 6 parts of antibacterial agent, 3 to 5 parts of water repellent and 10 to 20 parts of deionized water.

6. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 5, characterized in that: The dispersant is selected from any one of Shenzhen Haichuan's 963S dispersant, American Hemmings' 9086 dispersant, German BYK-163 dispersant, and German BYK-108 dispersant.

7. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 5, characterized in that: The defoamer is any one of Deqian 6500 defoamer, Haichuan E1 defoamer, and German BYK Chemical BYK-141 defoamer.

8. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 5, characterized in that: The filler is selected from any one of kaolin, talcum powder, calcium carbonate and mica powder.

9. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 5, characterized in that: The antibacterial agent is selected from any one of 5-chloro-2-methyl-4-isothiazoline-3-one and 2-methyl-4-isothiazoline-3-one.

10. The process for preparing water-resistant coated paper based on water-based acrylic resin coating according to claim 5, characterized in that: The preparation method of the water repellent is as follows: 5-10% hexadecyltriethoxysilane, 1.5-3.0% acetic acid and deionized water of the same mass as the acetic acid are added to anhydrous ethanol respectively, mixed and stirred evenly, and then stirred and reacted at a temperature of 40-60°C for 80-120 minutes; after the reaction is completed, perfluorooctane of the same mass as the anhydrous ethanol is added to the obtained product components, and the mixture is rapidly stirred at a temperature of 30-40°C for 5-10 hours, and the upper liquid is filtered out after standing, and the final product is the water repellent.

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