CN117165137A - Coating for printing and preparation method thereof - Google Patents

Abstract

The present application relates to the technical field of coatings, and in particular to a coating for printing and a preparation method thereof. A coating for printing, including the following raw materials in parts by mass: 50-55 parts of modified acrylic resin emulsion, 21-31 parts of modified composite filler, 3-5 parts of bistriazine aminostilbene, and zinc stearate 1-2 parts, 2-5 parts of dispersant, 2-5 parts of defoaming agent, 100-120 parts of water. The printing coating of the present application has excellent wear resistance, softness, high gloss, impact resistance and high adhesion, and meets the requirements of green environmental protection.

Description

Coating for printing and preparation method thereof

Technical field

The present application relates to the technical field of coatings, and in particular to a coating for printing and a preparation method thereof.

Background technique

Printing coating is a kind of coating used in the printing industry. It is used to form a thin film on the surface of paper, cardboard and other materials to realize the printing of patterns and text. Traditional printing coatings usually contain organic solvents, pigments, resins and other ingredients. However, with the increasing awareness of environmental protection, the requirements for the environmental friendliness of coatings are getting higher and higher. Therefore, it is necessary to develop an environmentally friendly coating with excellent performance. Printing coatings.

Contents of the invention

In order to solve the current technical problems, this application provides a coating for printing and a preparation method thereof.

In the first aspect, this application provides a coating for printing using the following technical solution:

A coating for printing, including the following raw materials in parts by mass: 50-55 parts of modified acrylic resin emulsion, 21-31 parts of modified composite filler, 3-5 parts of bistriazine aminostilbene, and zinc stearate 1-2 parts, dispersant 2-5 parts, defoaming agent 2-5 parts, water 100-120 parts.

By adopting the above technical solution, the modified acrylic resin emulsion provides the adhesiveness of the coating and the ability to form a protective film, and enhances the wear resistance, softness and adhesion of the coating. Modified composite fillers provide the coating with filling properties, improve compatibility with other components, and enhance the coating's wear resistance and impact resistance. Bistriazine amino stilbene prevents paint from yellowing and becoming brittle when exposed to sunlight. Zinc stearate promotes the drying and curing of coatings, increasing the hardness and adhesion of the coating. Dispersant: used to enhance the dispersion of various raw materials in liquid to make the paint particles evenly distributed. Defoaming agent: Used to prevent the generation and aggregation of bubbles in coatings and improve the coating performance and coating surface quality. Water: acts as a diluent to adjust the viscosity and concentration of the paint, making it easier to apply. The modified acrylic resin emulsion and the modified composite filler jointly provide the adhesiveness and filling performance of the coating, and enhance the wear resistance and adhesion of the coating.

Preferably, the preparation method of the modified acrylic resin emulsion includes the following steps:

S21. Preparation of pre-emulsion: Stir 10.4g sodium lauryl sulfate, 5.12g polyoxyethylene octylphenol and 200g deionized water until completely dissolved, continue stirring, then add 10.6g methyl methacrylate, 20.3 g butyl acrylate and 15.7g N-hydroxymethacrylamide are added, and stirring is continued for 30-40 minutes to obtain a pre-emulsion;

S22. Preparation of ammonium persulfate solution: prepare 100mL of ammonium persulfate solution with a mass solubility of 15g/L;

S23. Preparation of modified acrylic resin emulsion: In the reactor, add 100g deionized water, 5.6g methyl methacrylate, and 10.1g butyl acrylate and stir until completely dissolved. Use NaHCO3 solution with a mass solubility of 10g/L. Adjust the pH to 7.3, stir for a period of time, then add 10% of the total mass of the pre-emulsion in step S21, set the rotation speed to 200-250r/min, and when the temperature reaches 78°C, add 30mL of ammonium persulfate with a mass solubility of 15g/L solution to initiate the polymerization reaction. After 30-40 minutes of reaction, use a constant flow pump to drop the remaining pre-emulsion and ammonium persulfate solution at a constant speed. Control the reaction temperature to 78°C and control the pre-emulsion to finish dripping within 2 hours. The solution should be dripped within 5-10 minutes after the pre-emulsified liquid is dropped. After the dripping is completed, maintain 78°C and keep the reaction for 1-1.5h, then raise the temperature to 85°C, react for another 0.5h, naturally cool to room temperature, and finally use mass Adjust the pH of a NaHCO3 solution with a solubility of 10g/L to 7.3-7.5 to obtain a modified acrylic resin emulsion.

Preferably, the modified composite filler is a composition of calcium silicate, kaolin, and aluminum hydroxide in a mass ratio of 6:1-3:2-5.

Preferably, the particle size of the modified composite filler is 1000-1200 mesh.

Preferably, the calcium silicate, hydrokaolin and alumina have been modified. The method is: stir the calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol for 60 minutes, filter to obtain a solid, and dry it. deal with.

Preferably, the mass ratio of calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol is 6:1-3:2-5:0.03-0.05:20.

By adopting the above technical solution, the modified composite filler plays a role in filling and enhancing strength in the coating, and can increase the hardness, compatibility and wear resistance of the coating film. Calcium silicate modified by silane coupling agent provides the properties of increasing the adhesion and hardness of the coating film. Kaolin modified by silane coupling agent provides the properties of increasing the softness and adhesion of the coating film. The silane coupling agent Modified aluminum hydroxide provides properties that increase the impact resistance and scratch resistance of the coating.

Preferably, the dispersant is a composition of polyvinylpyrrolidone K30, octylphenol polyoxyethylene ether, and alkyl glycoside tartrate in a mass ratio of 1:1-3:2-5.

By adopting the above technical solution, the dispersant plays an important and synergistic role in the printing coating, as follows: Polyvinylpyrrolidone K30 can effectively disperse pigments and fillers evenly and prevent them from aggregating and precipitating again, thereby Maintain paint stability. Octylphenol polyoxyethylene ether has good dispersion stability and wetting properties. It can reduce surface tension in coatings, increase the contact area between pigments and substrates, and improve pigment dispersion and uniformity. Alkyl glycoside tartarates have excellent dispersing and emulsifying abilities. It effectively disperses pigments and fillers evenly and keeps them dispersed in the liquid. In addition, it improves the flow and wetting properties of coatings. The synergistic effect of these three dispersants in coating formulations helps to further improve the dispersion, stability and uniformity of coatings. They can work synergistically with each other to ensure that pigments and fillers are evenly dispersed and fully mixed with other raw materials, thereby ensuring the performance and use effect of the coating during the printing process. At the same time, these dispersants can also enhance the compatibility and adhesion between the coating and the substrate, and improve the wear resistance, softness, high gloss and impact resistance of the coating.

Preferably, the defoaming agent is a composition of fatty alcohol polyoxyethylene ether and fatty acid sodium in a mass ratio of 2:1-3.

By adopting the above technical solution, the function of the defoaming agent is to prevent bubbles from being generated during the preparation and application process of the coating, thereby ensuring the uniformity and quality of the coating. Fatty alcohol polyoxyethylene ether has the function of reducing the liquid surface tension, which can make the bubbles in the paint unstable and burst quickly, thereby eliminating the bubbles. Sodium fatty acid can improve the dispersion and wettability of liquid. In this application, fatty alcohol polyoxyethylene ether and fatty acid sodium are used together in a mass ratio of 2:1-3, which has a synergistic effect. Fatty alcohol polyoxyethylene ether can reduce the liquid surface tension and promote bubble bursting, while fatty acid sodium It can improve the wettability and dispersion of liquids and further help eliminate bubbles. The combined use of the two can enhance the defoaming effect of the coating, improve the quality of the coating, and ensure uniformity and stability during the coating process. At the same time, this defoaming agent combination also meets the requirements of green environmental protection, because fatty alcohol polyoxyethylene ether and fatty acid sodium are relatively environmentally friendly chemicals.

In a second aspect, this application provides a method for preparing a coating for printing, adopting the following technical solution:

A method for preparing a printing coating, using the raw materials of the above-mentioned printing coating, including the following steps:

S91. Stir and mix the modified acrylic resin emulsion, water, dispersant, modified composite filler and bistriazine amino stilbene according to the parts by mass. When the temperature reaches 50-55°C, continue stirring to prepare a mixed solution. ;

S92. Add zinc stearate and defoaming agent to the mixed solution in sequence according to parts by mass, stir evenly, and cool to room temperature to prepare a coating for printing.

Preferably, in step S1, the stirring time is 15-20 minutes, and in step S2, the stirring time is 5-10 minutes.

By adopting the above technical solution, the printing coating of the present application has excellent wear resistance, softness, high gloss, impact resistance and high adhesion, and meets the requirements of green environmental protection.

To sum up, the beneficial technical effects of this application are:

1. Excellent wear resistance: The modified acrylic resin emulsion and modified composite filler in the coating formula of this application have excellent wear resistance and can effectively resist scratches and friction during use and maintain the integrity of the coating. and aesthetics.

2. Softness: Due to the use of modified acrylic resin emulsion, the coating of this application has good softness, can adapt to the surface deformation and expansion of different substrates, and reduces the risk of cracking and peeling of the coating.

3. High gloss: Modified acrylic resin emulsion and ingredients in a special formula are used to give the coating high gloss, making the coating surface have good gloss and reflectivity, enhancing the aesthetics of the product.

4. High adhesion: The modified acrylic resin emulsion can form a strong chemical bond with the substrate during the curing process, and the adhesion of the coating is improved by adding an appropriate amount of zinc stearate, allowing the coating to adhere better on the substrate surface.

5. Impact resistance: Bistriazine amino stilbene is an excellent anti-impact agent, which can absorb energy when subjected to external impact, provide impact resistance of the coating, and effectively protect the substrate.

6. Green and environmental protection: The coating applied in this application does not contain harmful substances, meets the requirements of green and environmental protection, and is harmless to the human body and the environment. It has low volatile organic compounds (VOCs) emissions and complies with national environmental protection policies and standards.

Detailed ways

The embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application and should not be regarded as limiting the scope of the present application. If the specific conditions are not specified in the examples, the conditions should be carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not indicated, they are all conventional products that can be purchased commercially.

Example 1

A coating for printing, including the following raw materials in parts by mass: 50g modified acrylic resin emulsion, 21g modified composite filler, 3g bistriazine aminostilbene, 1g zinc stearate, 2g dispersant, defoaming agent 2g, 100g of water, the modified composite filler is a composition of calcium silicate, kaolin, and aluminum hydroxide in a mass ratio of 6:1:2, and the particle size of the modified composite filler is 1000-1200 mesh. The dispersant is a composition of polyvinylpyrrolidone K30, octylphenol polyoxyethylene ether, and alkyl glycoside tartrate in a mass ratio of 1:1:2, and the defoaming agent is fatty alcohol polyoxyethylene ether, fatty acid Sodium is a composition with a mass ratio of 2:1.

The preparation method of the modified acrylic resin emulsion includes the following steps:

S21. Preparation of pre-emulsion: Stir 10.4g sodium lauryl sulfate, 5.12g polyoxyethylene octylphenol and 200g deionized water until completely dissolved, continue stirring, then add 10.6g methyl methacrylate, 20.3 g butyl acrylate and 15.7g N-hydroxymethacrylamide were added, and stirring was continued for 30 minutes to obtain a pre-emulsion;

S22. Preparation of ammonium persulfate solution: prepare 100mL of ammonium persulfate solution with a mass solubility of 15g/L;

S23. Preparation of modified acrylic resin emulsion: In the reactor, add 100g deionized water, 5.6g methyl methacrylate, and 10.1g butyl acrylate and stir until completely dissolved. Use NaHCO3 solution with a mass solubility of 10g/L. Adjust the pH to 7.3, stir for a period of time, then add 10% of the total mass of the pre-emulsion in step S21, set the rotation speed to 200r/min, and when the temperature reaches 78°C, add 30mL of ammonium persulfate solution with a mass solubility of 15g/L. Initiate the polymerization reaction. After 30 minutes of reaction, use a constant flow pump to drop the remaining pre-emulsion and ammonium persulfate solution at a constant speed. Control the reaction temperature to 78°C and control the pre-emulsion to finish dripping within 2 hours. Complete the dripping within 5 minutes. After the dripping is completed, maintain 78°C and insulate for 1 hour. Then raise the temperature to 85°C, react for another 0.5 hours, cool to room temperature naturally, and finally use a NaHCO3 solution with a mass solubility of 10g/L. Adjust the pH to 7.3 to obtain a modified acrylic resin emulsion.

The calcium silicate, hydrokaolin and alumina have all been modified. The method is as follows: stir the calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol for 60 minutes, filter the solid, and dry it. The mass ratio of calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol is 6:1:2:0.03:20.

A method for preparing a printing coating, using the raw materials of the printing coating, including the following steps: S91. According to parts by mass, sequentially add modified acrylic resin emulsion, water, dispersant, and modified composite filler Stir and mix with bistriazine aminostilbene. When the temperature is raised to 50°C, continue stirring for 15 minutes to prepare a mixed solution;

S92. Add zinc stearate and defoaming agent to the mixed solution in sequence according to parts by mass, stir for 5 minutes, and cool to room temperature to prepare a coating for printing.

Example 2

A coating for printing, including the following raw materials in parts by mass: 55g of modified acrylic resin emulsion, 31g of modified composite filler, 5g of bistriazine aminostilbene, 2g of zinc stearate, 5g of dispersant, and defoaming agent 5g, 120g of water, the modified composite filler is a composition of calcium silicate, kaolin, and aluminum hydroxide in a mass ratio of 6:3:5, and the particle size of the modified composite filler is 1000-1200 mesh. The dispersant is a composition of polyvinylpyrrolidone K30, octylphenol polyoxyethylene ether, and alkyl glycoside tartrate in a mass ratio of 1:3:5, and the defoaming agent is fatty alcohol polyoxyethylene ether, fatty acid Sodium is a composition with a mass ratio of 2:3.

The preparation method of the modified acrylic resin emulsion includes the following steps:

S21. Preparation of pre-emulsion: Stir 10.4g sodium lauryl sulfate, 5.12g polyoxyethylene octylphenol and 200g deionized water until completely dissolved, continue stirring, then add 10.6g methyl methacrylate, 20.3 g butyl acrylate and 15.7g N-hydroxymethacrylamide were added, and stirring continued for 40 minutes to obtain a pre-emulsion;

S22. Preparation of ammonium persulfate solution: prepare 100mL of ammonium persulfate solution with a mass solubility of 15g/L;

S23. Preparation of modified acrylic resin emulsion: In the reactor, add 100g deionized water, 5.6g methyl methacrylate, and 10.1g butyl acrylate and stir until completely dissolved. Use NaHCO3 solution with a mass solubility of 10g/L. Adjust the pH to 7.3, stir for a period of time, then add 10% of the total mass of the pre-emulsion in step S21, set the rotation speed to 250r/min, and when the temperature reaches 78°C, add 30mL of ammonium persulfate solution with a mass solubility of 15g/L. Initiate the polymerization reaction. After 40 minutes of reaction, use a constant flow pump to drop the remaining pre-emulsion and ammonium persulfate solution at a constant speed. Control the reaction temperature to 78°C and control the pre-emulsion to finish dripping within 2 hours. The ammonium persulfate solution is still pre-emulsified. Complete the dripping within 10 minutes after the dripping is completed. After the dripping is completed, maintain 78°C and insulate for 1.5h, then raise the temperature to 85°C, react for another 0.5h, naturally cool to room temperature, and finally use NaHCO3 with a mass solubility of 10g/L. The pH of the solution was adjusted to 7.5 to obtain a modified acrylic resin emulsion.

The calcium silicate, hydrokaolin and alumina have all been modified. The method is as follows: stir the calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol for 60 minutes, filter the solid, and dry it. The mass ratio of calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol is 6:3:5:0.05:20.

A method for preparing a printing coating, using the raw materials of the printing coating, including the following steps: S91. According to parts by mass, sequentially add modified acrylic resin emulsion, water, dispersant, and modified composite filler Stir and mix with bistriazine aminostilbene. When the temperature is raised to 55°C, continue stirring for 20 minutes to prepare a mixed solution;

S92. Add zinc stearate and defoaming agent to the mixed solution in sequence according to parts by mass, stir for 10 minutes, and cool to room temperature to prepare a coating for printing.

Example 3

A coating for printing, including the following raw materials in parts by mass: 53g modified acrylic resin emulsion, 25g modified composite filler, 4g bistriazine aminostilbene, 1.5g zinc stearate, 4g dispersant, defoaming 3g of agent and 110g of water. The modified composite filler is a composition of calcium silicate, kaolin and aluminum hydroxide in a mass ratio of 6:2:4. The particle size of the modified composite filler is 1000-1200 mesh. , the dispersant is a composition of polyvinylpyrrolidone K30, octylphenol polyoxyethylene ether, and alkyl glycoside tartrate in a mass ratio of 1:2:3, and the defoaming agent is fatty alcohol polyoxyethylene ether, A composition of sodium fatty acid in a mass ratio of 2:2.

The preparation method of the modified acrylic resin emulsion includes the following steps:

S21. Preparation of pre-emulsion: Stir 10.4g sodium lauryl sulfate, 5.12g polyoxyethylene octylphenol and 200g deionized water until completely dissolved, continue stirring, then add 10.6g methyl methacrylate, 20.3 g butyl acrylate and 15.7g N-hydroxymethacrylamide were added, and stirring was continued for 35 minutes to obtain a pre-emulsion;

S22. Preparation of ammonium persulfate solution: prepare 100mL of ammonium persulfate solution with a mass solubility of 15g/L;

S23. Preparation of modified acrylic resin emulsion: In the reactor, add 100g deionized water, 5.6g methyl methacrylate, and 10.1g butyl acrylate and stir until completely dissolved. Use NaHCO3 solution with a mass solubility of 10g/L. Adjust the pH to 7.3, stir for a period of time, then add 10% of the total mass of the pre-emulsion in step S21, set the rotation speed to 230r/min, and when the temperature reaches 78°C, add 30mL of ammonium persulfate solution with a mass solubility of 15g/L. Initiate the polymerization reaction. After 35 minutes of reaction, use a constant flow pump to drop the remaining pre-emulsion and ammonium persulfate solution at a constant speed. Control the reaction temperature to 78°C and control the pre-emulsion to finish dripping within 2 hours. Complete the dripping within 8 minutes. After the dripping is completed, maintain 78°C and insulate for 1.2h, then raise the temperature to 85°C, react for another 0.5h, cool to room temperature naturally, and finally use NaHCO3 with a mass solubility of 10g/L. The pH of the solution was adjusted to 7.4 to obtain a modified acrylic resin emulsion.

The calcium silicate, hydrokaolin and alumina have all been modified. The method is as follows: stir the calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol for 60 minutes, filter the solid, and dry it. The mass ratio of calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol is 6:2:4:0.04:20.

A method for preparing a printing coating, using the raw materials of the printing coating, including the following steps: S91. According to parts by mass, sequentially add modified acrylic resin emulsion, water, dispersant, and modified composite filler Stir and mix with bistriazine aminostilbene. When the temperature rises to 53°C, continue stirring for 18 minutes to prepare a mixed solution;

S92. Add zinc stearate and defoaming agent to the mixture in sequence according to parts by mass, stir for 8 minutes, and cool to room temperature to prepare a coating for printing.

Comparative example 1

The same as Example 3, except that an equal amount of water-based acrylic resin is used instead of the modified acrylic resin emulsion of the present application.

Comparative example 2

The same as Example 3, except that the modified composite filler is an equal amount of calcium silicate, the particle size of the calcium silicate is 1000-1200 mesh, and it has not passed through the silane coupling agent of the present application. KH550 modification treatment.

Comparative example 3

The same as Example 3, except that the modified composite filler is an equal amount of aluminum hydroxide, the particle size of the aluminum hydroxide is 1000-1200 mesh, and it has not passed through the silane coupling agent of the present application. KH550 modification treatment.

Comparative example 4

The same as Example 3, except that the modified composite filler is an equal amount of kaolin, the particle size of the kaolin is 1000-1200 mesh, and it has not been modified by the silane coupling agent KH550 of the present application. .

Comparative example 5

The same as Example 3, except that the dispersant is an equal amount of polyvinylpyrrolidone K30.

Comparative example 6

The same as Example 3, except that the dispersant is an equal amount of octylphenol polyoxyethylene ether.

Comparative example 7

The same as Example 3, except that the dispersant is an equal amount of alkyl glycoside tartrate.

Performance Testing

Adhesion test: Use the standard GB/T9286-1998 for testing. Those that reach level 0 are qualified, and those that are greater than or equal to level 2 are considered poor;

Deep drawing performance: Tested using the standard GB/T1732-1993, the one with a forward punch of 50cm and a backlash of 50cm is considered good, the one with a forward punch of 50cm and a backlash of 10cm is average, and the one with a forward punch of 10cm and a backlash of 10cm is poor.

Hardness test: Tested using standard GB/673986.

Flexibility test: tested using standard GB/173179.

Glossiness: Use a gloss meter to measure the glossiness of ceramics by testing specimens piece by piece with a 60° geometry. The instrument emits a beam of light onto the ceramic surface, measures the amount of reflected light, and displays the result as a value. Generally speaking, the higher the value, the better the gloss.

The printing coating prepared in Examples 1-3 and Comparative Examples 1-7 of the present application is evenly coated on a transparent glass plate with a coating thickness of 0.1-0.3mm and dried. After the film is formed, the above performance test is performed. The test results As shown in Table 1.

Table 1 Performance test table

Adhesion/level Deep drawing performance hardness Flexibility/mm Gloss Example 1 1 good B 2 98 Example 2 1 good B 2 99 Example 3 1 good B 2 98 Comparative example 1 3 Difference 5B 1 93 Comparative example 2 1 generally 2B 2 94 Comparative example 3 1 generally 2B 2 92 Comparative example 4 1 generally 2 2 93 Comparative example 5 2 generally B 1.5 91 Comparative example 6 2 generally B 1.5 92 Comparative example 7 2 generally B 1.5 90

It can be seen from Example 13 and Table 1 that the printing coating prepared in this application has better performance in terms of coating hardness, adhesion, flexibility, deep drawing performance and gloss.

Combining Example 3 and Comparative Example 1 and Table 1, it can be seen that the hardness, adhesion, flexibility and deep drawing performance of the coating obtained by using an equal amount of water-based acrylic resin instead of the modified acrylic resin emulsion of the present application Poor performance in terms of gloss and gloss.

Combining Example 3 and Comparative Examples 2-4 and Table 1, it can be seen that the modified composite filler is a composition of calcium silicate, kaolin, and aluminum hydroxide in a mass ratio of 6:2:4, and after The coating obtained by modifying the silane coupling agent KH550 has better coating properties than the coating obtained by calcium silicate, kaolin or aluminum hydroxide alone. This is because the modified composite filler plays a filling role in the coating. And the effect of enhancing strength can increase the hardness, compatibility and deep drawing performance of the coating film. Calcium silicate modified by silane coupling agent provides the properties of increasing the adhesion and hardness of the coating film. Kaolin modified by silane coupling agent provides the properties of increasing the softness and adhesion of the coating film. The silane coupling agent Modified aluminum hydroxide provides increased impact resistance to the coating.

Combining Example 3 and Comparative Examples 5-7 and Table 1, it can be seen that the dispersant used is polyvinylpyrrolidone K30, octylphenol polyoxyethylene ether, and alkyl glycoside tartrate according to the mass ratio of 1:2: The coating performance of the coating obtained by the composition of 3 is better than that of the coating obtained by polyvinylpyrrolidone K30, octylphenol polyoxyethylene ether, and alkyl glycoside tartrate alone.

The above embodiments are only used to explain the technical solutions of the present invention but not to limit them. Although the above embodiments specifically describe the present invention, those skilled in the art should understand that the specific embodiments of the present invention can still be modified or equivalently substituted. , and any modifications and equivalent substitutions that do not depart from the spirit and scope of the present invention shall be covered by the claims of the present invention.

Claims (10)

1. A coating for printing, characterized in that it includes the following raw materials in parts by mass: 50-55 parts of modified acrylic resin emulsion, 21-31 parts of modified composite filler, 3-5 parts of bistriazine amino stilbene parts, 1-2 parts of zinc stearate, 2-5 parts of dispersant, 2-5 parts of defoaming agent, and 100-120 parts of water. 2. A kind of coating for printing according to claim 1, characterized in that the preparation method of the modified acrylic resin emulsion includes the following steps: S21. Preparation of pre-emulsion: Stir 10.4g sodium lauryl sulfate, 5.12g polyoxyethylene octylphenol and 200g deionized water until completely dissolved, continue stirring, then add 10.6g methyl methacrylate, 20.3 g butyl acrylate and 15.7g N-hydroxymethacrylamide are added, and stirring is continued for 30-40 minutes to obtain a pre-emulsion; S22. Preparation of ammonium persulfate solution: prepare 100mL of ammonium persulfate solution with a mass solubility of 15g/L; S23. Preparation of modified acrylic resin emulsion: In the reactor, add 100g deionized water, 5.6g methyl methacrylate, and 10.1g butyl acrylate and stir until completely dissolved. Use NaHCO3 solution with a mass solubility of 10g/L. Adjust the pH to 7.3, stir for a period of time, then add 10% of the total mass of the pre-emulsion in step S21, set the rotation speed to 200-250r/min, and when the temperature reaches 78°C, add 30mL of ammonium persulfate with a mass solubility of 15g/L solution to initiate the polymerization reaction. After 30-40 minutes of reaction, use a constant flow pump to drop the remaining pre-emulsion and ammonium persulfate solution at a constant speed. Control the reaction temperature to 78°C and control the pre-emulsion to finish dripping within 2 hours. The ammonium solution should be dripped within 5-10 minutes after the pre-emulsified solution is dropped. After the dripping is completed, maintain 78°C and insulate for 1-1.5 hours, then raise the temperature to 85°C, react for another 0.5 hours, naturally cool to room temperature, and finally use Adjust the pH of a NaHCO3 solution with a mass solubility of 10g/L to 7.3-7.5 to obtain a modified acrylic resin emulsion. 3. A kind of coating for printing according to claim 1, characterized in that the modified composite filler is a combination of calcium silicate, kaolin, and aluminum hydroxide in a mass ratio of 6:1-3:2-5. things. 4. A coating for printing according to claim 3, characterized in that the particle size of the modified composite filler is 1000-1200 mesh. 5. A kind of coating for printing according to claim 3 or 4, characterized in that the calcium silicate, kaolin and alumina have been modified by the method: adding calcium silicate, kaolin, hydroxide Magnesium, silane coupling agent KH550 and ethanol were stirred for 60 minutes, filtered to obtain a solid, and dried. 6. A kind of coating for printing according to claim 5, characterized in that the mass ratio of the calcium silicate, kaolin, magnesium hydroxide, silane coupling agent KH550 and ethanol is 6:1-3:2- 5:0.03-0.05:20. 7. A kind of coating for printing according to claim 1, characterized in that, the dispersant is polyvinylpyrrolidone K30, octylphenol polyoxyethylene ether, alkyl glycoside tartrate according to the mass ratio of 1:1- 3:2-5 composition. 8. A coating for printing according to claim 1, characterized in that the defoaming agent is a composition of fatty alcohol polyoxyethylene ether and sodium fatty acid in a mass ratio of 2:1-3. 9. A method for preparing a printing coating, characterized in that, using the raw material of a printing coating according to any one of claims 18, the method includes the following steps: S91. Stir and mix the modified acrylic resin emulsion, water, dispersant, modified composite filler and bistriazine amino stilbene according to the parts by mass. When the temperature reaches 50-55°C, continue stirring to prepare a mixed solution. ; S92. Add zinc stearate and defoaming agent to the mixed solution in sequence according to parts by mass, stir evenly, and cool to room temperature to prepare a coating for printing. 10. The preparation method of a printing coating according to claim 9, characterized in that, in step S1, the stirring time is 15-20 minutes, and in step S2, the stirring time is 5-10 minutes.