Acrylic acid dispersion, preparation method and water-based transfer coating

Abstract

In order to solve the problems of poor stripping property and poor transferability of a water-based transfer coating in the prior art, the invention provides an acrylic acid dispersion, a preparation method and the water-based transfer coating. The acrylic dispersion comprises a modified acrylic polymer, polymeric monomers of the modified acrylic polymer comprise an unsaturated polymeric monomer, an acrylic cross-linking monomer and allyl polyether, and the acrylic cross-linking monomer contains hydroxyl. In the invention, the polyether chain segment of the polymerized allyl polyether has affinity on the surface of a coated base material on a coating layer prepared from the acrylic acid dispersion, so that the allyl polyether is enriched on a contact interface between the coating layer and the base material, and the stripping force between the coating layer and the base material is reduced; the polymerized acrylic acid crosslinking monomer enables the coating to be changed from a linear structure of a polymer chain segment to a net structure through crosslinking, free migration of a polyether chain segment of allyl polyether is limited, the problem that the stripping force of the coating is increased due to migration of the polyether chain segment in the product placing process is solved, and the stripping property and the transfer property of the transfer coating are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of transfer coatings, and in particular relates to an acrylic acid dispersion and a preparation method thereof, and a water-based transfer coating. Background Art

[0002] Transfer paper is a new type of packaging material with advantages such as environmental protection and defense. It is widely used in the fields of tobacco, alcohol, food, daily necessities, etc. The surface of general base paper is rough and uneven, and the glossiness is low after printing. The uneven printing surface has missing points, and the base paper has high ink absorption, resulting in a large ink consumption. Through the transfer process, a layer of smooth and high-gloss coating is applied on the surface of the base paper, which can not only reduce the ink absorption of the base paper and reduce the amount of ink, but also make the printed products have better fullness and glossiness. Therefore, the application of transfer coating in base paper treatment is becoming more and more extensive.

[0003] There are some oily and water-based transfer coatings on the market. Oily transfer coatings have good transferability, but contain high volatile organic solvents, which pose a greater risk of harm to the environment and operators. Water-based transfer coatings have a greater force on PET. Currently, the main method is to add some small molecule compounds such as silicone to reduce the force between the coating and PET, so as to achieve the effect of peeling and transfer. However, these small molecule compounds such as silicone can reduce the surface tension of the coating, thereby affecting the appearance of printing leveling, and during the coating placement process, the small molecule compounds will migrate, resulting in the problem of increased peeling force of the coating. Summary of the invention

[0004] Aiming at the problem of poor stripping and transferability of water-based transfer coatings in the prior art, an acrylic dispersion and a preparation method thereof and a water-based transfer coating are provided.

[0005] The technical solution adopted by the present invention to solve the above technical problems is as follows: In one aspect, the present invention provides an acrylic dispersion, comprising a modified acrylic polymer, wherein the polymerized monomers of the modified acrylic polymer comprise an unsaturated polymerized monomer, an acrylic crosslinking monomer and an allyl polyether, wherein the acrylic crosslinking monomer contains a hydroxyl group.

[0006] Optionally, the unsaturated polymerizable monomer includes one or more of methyl methacrylate, butyl acrylate, styrene and isobornyl methacrylate.

[0007] Optionally, the acrylic cross-linking monomer includes one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate, N-hydroxymethyl acrylate, N-hydroxyethyl acrylate and N-hydroxyethyl acrylamide.

[0008] Optionally, the raw materials for preparing the acrylic dispersion include the following mass components: Unsaturated polymerizable monomer 30-35 parts 3-5 parts of acrylic acid cross-linking monomer Allyl polyether 3-5 parts Initiator 1-3 parts 5-7 parts of the first solvent 3-5 parts of neutralizer.

[0009] Optionally, the acrylic dispersion further comprises a carboxyl unsaturated polymerizable monomer, wherein the carboxyl unsaturated polymerizable monomer is 7-10 parts; The carboxyl unsaturated polymerizable monomer includes one or more of acrylic acid and methacrylic acid.

[0010] Optionally, the initiator includes one or more of azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate and benzoyl peroxide; and / or, the first solvent includes one or more of propylene glycol methyl ether and dipropylene glycol ethyl ether.

[0011] Optionally, the method for preparing the acrylic dispersion provided by the present invention comprises the following operations: The unsaturated polymerizable monomer, the carboxyl unsaturated polymerizable monomer, the acrylic acid crosslinking monomer and the allyl polyether are mixed with an initiator in a first solvent to react to obtain an acrylic acid polymer; A neutralizing agent is added to an acrylic polymer and dispersed in deionized water to obtain a modified acrylic dispersion.

[0012] On the other hand, the present invention provides a water-based transfer coating, comprising the acrylic dispersion, or the acrylic dispersion prepared by the method for preparing the acrylic dispersion.

[0013] Optionally, the following quality components may be included: Modified acrylic dispersion 40-60 parts 15-25 parts of the second solvent Additives 0.1-1 parts 15-35 parts of deionized water.

[0014] Optionally, the second solvent includes one or more of ethanol, isopropanol, n-butanol and dipropylene glycol dimethyl ether; and / or the auxiliary agent includes one or more of a leveling agent, a defoaming agent and a thickener.

[0015] The beneficial effects of the present invention are: In the acrylic dispersion provided by the present invention, the acrylic crosslinking monomer and the acryl polyether are prepolymerized with the unsaturated polymerized monomer to obtain a modified acrylic polymer. After the transfer coating prepared by the modified acrylic dispersion is coated, the polyether segment of the allyl polyether in the modified acrylic dispersion has affinity for the coating and the surface of the coated substrate, so that the allyl polyether tends to be enriched at the interface between the coating and the substrate, which is beneficial to reducing the peeling force between the coating formed by the coating and the substrate. The lower peeling force can ensure the complete transfer of the coating, thereby improving the transferability of the coating. During the coating placement process, the polyether segment in the allyl polyether has a migration problem, and the migration of the polyether segment causes the peeling force of the coating to increase. At this time, the acrylic crosslinking monomer polymerized on the unsaturated polymerized monomer plays a self-crosslinking role, and the polyether segment in the allyl polyether forms a polymer segment network structure through crosslinking, thereby limiting the migration of the polyether segment. That is, by prepolymerizing the acrylic crosslinking monomer and the acryl polyether on the unsaturated polymerized monomer, the peeling and transferability of the transfer coating are improved together. DETAILED DESCRIPTION

[0016] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0017] The invention provides an acrylic dispersion, comprising a modified acrylic polymer, wherein the polymerized monomers of the modified acrylic polymer comprise an unsaturated polymerized monomer, an acrylic cross-linking monomer and allyl polyether, and the acrylic cross-linking monomer contains a hydroxyl group.

[0018] Specifically, in the acrylic dispersion provided by the present invention, the acrylic crosslinking monomer and the acryl polyether are polymerized with the unsaturated polymerization monomer to obtain a modified acrylic polymer. After the transfer coating prepared by the modified acrylic polymer is coated, the polyether segment of the allyl polyether polymerized on the modified acrylic has affinity for the coating and the surface of the coating substrate, so that the allyl polyether tends to be enriched at the interface between the coating and the substrate, which is beneficial to reduce the peeling force between the coating formed by the coating and the substrate. The lower peeling force can ensure the complete transfer of the coating, thereby improving the transferability of the coating; during the coating placement process, the polyether segment in the allyl polyether has a migration problem, and the migration of the polyether segment causes the peeling force of the coating to increase. At this time, the acrylic crosslinking monomer polymerized on the unsaturated polymerization monomer plays a self-crosslinking role, and the polyether segment in the allyl polyether forms a polymer segment network structure through crosslinking, thereby limiting the migration of the polyether segment, that is, by pre-polymerizing the acrylic crosslinking monomer and the acryl polyether on the unsaturated polymerization monomer, the peeling and transferability of the transfer coating are jointly improved.

[0019] In addition, the polymerized acrylic cross-linking monomer forms a coating with a network structure through self-cross-linking, which makes the internal structure of the coating become tighter and more stable, thereby improving the solvent resistance of the prepared transfer coating coating. The presence of allyl polyether increases the surface tension of the coating, so that the subsequent printing ink has better leveling properties on the coating surface, and the final printed product has better fullness and gloss.

[0020] In some embodiments, the unsaturated polymerizable monomer includes one or more of methyl methacrylate, butyl acrylate, styrene, and isobornyl methacrylate.

[0021] Unsaturated polymer monomers are key raw materials for constructing the polymer skeleton of coatings. Unsaturated polymer monomers can give coatings corresponding properties by adjusting their chemical structure and composition. The long-chain alkyl group in the butyl acrylate molecule has good flexibility. In the transfer coating, the flexibility enables the coating to better adapt to the shape changes of the coated object, ensuring the integrity and good transferability of the coating; the special structure of isobornyl methacrylate can reduce the shrinkage rate after polymerization, reduce the stress caused by shrinkage between the coating and the substrate, and is beneficial to the integrity and stability of the transfer coating during the transfer process; methyl methacrylate has a high hardness. In the transfer coating, this hardness property can enable the coating to form a solid surface after transfer, resist scratches from external objects, and maintain the integrity and aesthetics of the coating surface.

[0022] In some embodiments, the acrylic crosslinking monomer includes one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate, N-hydroxymethyl acrylate, N-hydroxyethyl acrylate, and N-hydroxyethyl acrylamide.

[0023] Specifically, the hydroxyl group in the molecular structure of hydroxyethyl methacrylate and hydroxypropyl methacrylate reacts with other monomers or polymer chains containing active groups during the coating formation process to form a cross-linked structure, thereby improving the cohesion of the coating; the hydroxymethyl group in the N-hydroxymethyl acrylate molecule can react with itself or other active groups to form a highly cross-linked structure; the amide group and hydroxyethyl group in the N-hydroxyethyl acrylamide molecule, the amide group participates in multiple reactions, and the hydroxyethyl group provides additional cross-linking sites. The presence of dual active groups enables it to enhance the performance of the coating from multiple angles when forming a cross-linked structure. In the transfer coating, the cross-linked coating formed by N-hydroxyethyl acrylamide can effectively prevent moisture penetration and improve the water resistance of the coating.

[0024] The molecular weight of the allyl polyether is 400-2400.

[0025] In some embodiments, the raw materials for preparing the acrylic dispersion include the following mass components: Unsaturated polymerizable monomer 30-35 parts 3-5 parts of acrylic acid cross-linking monomer Allyl polyether 3-5 parts Initiator 1-3 parts 5-7 parts of the first solvent 3-5 parts of neutralizer.

[0026] Specifically, the present application polymerizes the unsaturated polymer monomer with the acrylic acid crosslinking monomer and the acrylic polyether to obtain a prepolymer of the three, which jointly improves the stripping and transfer properties of the transfer coating. In the process of preparing the acrylic acid dispersion, an initiator, a neutralizer and a first solvent need to be added for auxiliary effects; The initiator is a key factor in the polymerization reaction, which can initiate the polymerization reaction of unsaturated polymer monomers; the first solvent is used to dissolve the above-mentioned multiple raw material components in the acrylic dispersion, so that the raw materials can be evenly mixed and reacted; the neutralizer neutralizes the acidic group to improve the dispersibility of the polymer in water.

[0027] In a specific embodiment, the added amount of the unsaturated polymerization monomer can be 30 parts, 32 parts, 33 parts, 34 parts or 35 parts; the added amount of the acrylic cross-linking monomer can be 3 parts, 4 parts or 5 parts; the added amount of the allyl polyether can be 3 parts, 4 parts or 5 parts; the added amount of the initiator can be 1 part, 2 parts or 3 parts; the added amount of the first solvent can be 5 parts, 6 parts or 7 parts.

[0028] In some embodiments, the acrylic dispersion further comprises a carboxylic acid acrylic monomer, wherein the carboxylic acid acrylic monomer is 7-10 parts; The carboxyl acrylic monomer includes one or more of acrylic acid and methacrylic acid.

[0029] Specifically, during the preparation of the acrylic dispersion, carboxyl acrylic monomers are added. The hydrophilicity of the carboxyl acrylic monomers helps to disperse them in the aqueous system, which is beneficial for forming a water-based transfer coating with stable performance and uniform quality in the subsequent preparation.

[0030] In a specific embodiment, the added amount of the unsaturated polymerizable monomer may be 7 parts, 8 parts, 9 parts or 10 parts.

[0031] In some embodiments, the initiator includes one or more of azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, and benzoyl peroxide; and / or, the first solvent includes one or more of propylene glycol methyl ether and dipropylene glycol ethyl ether.

[0032] In some embodiments, the method for preparing the acrylic dispersion provided by the present invention comprises the following operations: S1: mixing an unsaturated polymerizable monomer, a carboxyl acrylic acid monomer, an acrylic acid crosslinking monomer, and an allyl polyether with an initiator in a first solvent to react to obtain an acrylic acid polymer; S2: A neutralizing agent is added to an acrylic polymer and dispersed in deionized water to obtain a modified acrylic dispersion.

[0033] The preparation method of the acrylic acid dispersion specifically comprises the following operations: Heat the first solvent to 80-120°C; The unsaturated polymerization monomer, the carboxyl acrylic acid monomer, the acrylic acid cross-linking monomer, the allyl polyether and the initiator are mixed and reacted to obtain a mixed solution; Add part of the mixed solution dropwise to the first solvent within 4 hours, and keep warm for 1 hour after the addition is complete; The remaining mixed solution was added dropwise to the first solvent within 2 hours, and the mixture was kept warm for 2 hours after the addition was completed; The mixture was cooled to 40-60°C, ethanolamine was added for neutralization and dispersed in deionized water to obtain a modified acrylic acid dispersion.

[0034] Unsaturated polymer monomers, carboxyl acrylic monomers, acrylic crosslinking monomers, allyl polyethers and initiators are mixed and reacted in a certain proportion and order to obtain a mixed solution. In this process, the initiator triggers the polymerization reaction of unsaturated polymer monomers and other double-bond compounds. The monomers cooperate with each other. The unsaturated polymer monomers construct the main chain skeleton of the polymer, the carboxyl acrylic monomers provide hydrophilic groups and sites that can participate in crosslinking reactions, and the acrylic crosslinking monomers are used to form a crosslinking structure in the subsequent process to enhance the coating performance.

[0035] In another embodiment, the present invention provides a water-based transfer coating, comprising the acrylic dispersion described above, or the acrylic dispersion prepared by the method for preparing the acrylic dispersion described above.

[0036] In some embodiments, the raw materials for preparing the water-based transfer coating include the following mass components: Modified acrylic dispersion 40-60 parts 15-25 parts of the second solvent Additives 0.1-1 parts 15-35 parts of deionized water.

[0037] Specifically, the water-based transfer coating provided in the present application includes the modified acrylic dispersion, and it can be seen from the added amounts of multiple components of the water-based transfer coating that the modified acrylic dispersion, as the main component for preparing the coating, is polymerized through the unsaturated polymerization monomer, the acrylic cross-linking monomer and the acrylic polyether to jointly improve the stripping and transferability of the subsequently prepared transfer coating.

[0038] In a specific embodiment, the added amount of the modified acrylic dispersion can be 40 parts, 50 parts or 60 parts; the added amount of the second solvent can be 15 parts, 20 parts or 25 parts; the added amount of the auxiliary agent can be 0.1 parts, 0.5 parts or 1 parts; the added amount of the deionized water can be 15 parts, 25 parts, 29 parts or 35 parts.

[0039] In some embodiments, the second solvent includes one or more of ethanol, isopropanol, n-butanol and dipropylene glycol dimethyl ether; and / or, the auxiliary agent includes one or more of a leveling agent, a defoaming agent and a thickener.

[0040] The present invention is further described below by way of examples.

[0041] Example 1 This example is used to illustrate an acrylic dispersion and a preparation method and a water-based transfer coating disclosed in the present invention, and includes the following steps: Preparation of modified acrylic dispersion: Take 5 parts of propylene glycol methyl ether and add them into a flask, heat to 80°C and set aside; 32 parts of methyl methacrylate, 7 parts of methacrylic acid, 3 parts of N-hydroxyethyl acrylamide, 3 parts of allyl polyether and 1 part of benzoyl peroxide were mixed and reacted to obtain a mixed solution; Add part of the mixed solution dropwise to the first solvent within 4 hours, and keep warm for 1 hour after the addition is complete; The remaining mixed solution was added dropwise to the first solvent within 2 hours, and the mixture was kept warm for 2 hours after the addition was completed; The mixture was cooled to 40°C, ethanolamine was added for neutralization and dispersed in deionized water to obtain a modified acrylic acid dispersion.

[0042] Preparation of water-based transfer coating: 50 parts of modified acrylic acid dispersion, 20 parts of ethanol and 29 parts of deionized water were mixed in a reaction kettle and stirred at 300 rpm for 10 min; The stirring speed was increased to 600 rpm, 1 part of an auxiliary agent was added, stirred for 10 minutes, and then filtered using a 300-mesh filter to obtain a water-based transfer coating.

[0043] Example 2 This example is used to illustrate an acrylic dispersion and preparation method and a water-based transfer coating disclosed in the present invention, and includes most of the steps in Example 1, except that: When preparing the modified acrylic dispersion, the added amount of the allyl polyether is 5 parts.

[0044] Example 3 This example is used to illustrate an acrylic dispersion and preparation method and a water-based transfer coating disclosed in the present invention, and includes most of the steps in Example 1, except that: When preparing the modified acrylic dispersion, the amount of the acrylic cross-linking monomer added is 5 parts.

[0045] Example 4 This example is used to illustrate an acrylic dispersion and preparation method and a water-based transfer coating disclosed in the present invention, and includes most of the steps in Example 1, except that: When preparing the modified acrylic dispersion, the amount of the acrylic crosslinking monomer added is 5 parts, and the amount of the allyl polyether added is 5 parts.

[0046] Example 5 This example is used to illustrate an acrylic dispersion and preparation method and a water-based transfer coating disclosed in the present invention, and includes most of the steps in Example 1, except that: When preparing the water-based transfer coating, the modified acrylic dispersion is added in an amount of 40 parts.

[0047] Example 6 This example is used to illustrate an acrylic dispersion and preparation method and a water-based transfer coating disclosed in the present invention, and includes most of the steps in Example 1, except that: When preparing the water-based transfer coating, the modified acrylic dispersion is added in an amount of 60 parts.

[0048] Comparative Example 1 This comparative example is used to compare and illustrate an acrylic dispersion and preparation method and a water-based transfer coating disclosed in the present invention, and includes most of the steps in Example 1, except that: When preparing the modified acrylic dispersion, no allyl polyether is added.

[0049] Comparative Example 2 This comparative example is used to compare and illustrate an acrylic dispersion and preparation method and a water-based transfer coating disclosed in the present invention, and includes most of the steps in Example 1, except that: When preparing the modified acrylic dispersion, no acrylic crosslinking monomer is added.

[0050] Comparative Example 3 This comparative example uses a commercially available water-based transfer coating to compare and illustrate an acrylic dispersion and a preparation method and a water-based transfer coating disclosed in the present invention.

[0051] Performance Testing The following performance tests were performed on Examples 1-6 and Comparative Examples 1-3 prepared as above: Peel force test method: Tested on a tape peel force tester PT-501C.

[0052] Test method for the number of alcohol wipes: The coating is transferred to cardboard, a 1kg standard weight wrapped with a dust-free cloth is soaked with alcohol, placed horizontally and pushed and pulled back and forth with force to examine the number of wipes required for the coating to be destroyed.

[0053] Test method for the number of times the coating is rubbed against ethyl acetate: The coating is transferred to cardboard, a 1kg standard weight wrapped with a dust-free cloth is soaked with ethyl acetate, placed horizontally and pushed and pulled back and forth with force, and the number of times the coating is wiped until it is damaged is observed.

[0054] Test method for leveling of gravure ink after transfer: After the coated transfer film is transferred to the base paper, peel off the PET film, print ordinary oil-based ink on the release layer with a small gravure printer, and observe whether there are obvious leveling defects.

[0055] The test results obtained are entered in Table 1.

[0056] Table 1 From the test results in Table 1, it can be seen that the coatings of Examples 1-6 have low and stable peeling force, high surface tension, good solvent resistance and printing leveling; compared with Examples 1-3, the peeling force of the coating prepared in Example 4 is relatively low and stable, because when preparing the coating in Example 4, the addition amount of allyl polyether and acrylic acid cross-linking monomer is relatively large, so it has low and stable peeling force; compared with Example 1, in the coating prepared in Example 6, the addition amount of modified acrylic acid dispersion is higher, so it has low peeling force and still has low peeling force after being placed; The test results of Examples 1-6 and Comparative Example 1 show that Comparative Example 1 cannot be peeled off and has poor printing leveling. The reason is that the allyl polyether in Examples 1-6 can significantly reduce the peeling force between the coating and the substrate, so that the coating has better transferability, and at the same time improves the surface tension of the coating, so that the ink has a better leveling effect on the coating surface; Compared with Example 2, the acrylic acid cross-linking monomers in Examples 1-6 form a coating with a network structure through self-cross-linking, so that the internal structure of the coating becomes tighter and more stable, thereby improving the solvent resistance of the prepared transfer coating coating, and at the same time limiting the migration of the polyether chain segments, so that the coating has a stable peeling force. In Comparative Example 2, no acrylic acid cross-linking monomer is added, so its peeling force stability is poor.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An acrylic dispersion, characterized in that: The invention comprises a modified acrylic polymer, wherein the polymerized monomers of the modified acrylic polymer comprise an unsaturated polymerized monomer, an acrylic cross-linking monomer and an allyl polyether, and the acrylic cross-linking monomer contains a hydroxyl group.

2. An acrylic dispersion according to claim 1, characterized in that: The unsaturated polymerizable monomers include one or more of methyl methacrylate, butyl acrylate, styrene and isobornyl methacrylate.

3. An acrylic dispersion according to claim 1, characterized in that: The acrylic cross-linking monomer includes one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate, N-hydroxymethyl acrylate, N-hydroxyethyl acrylate and N-hydroxyethyl acrylamide.

4. An acrylic dispersion according to claim 1, characterized in that: The raw materials for preparing the acrylic dispersion include the following mass components: Unsaturated polymerizable monomer 30-35 parts 3-5 parts of acrylic acid cross-linking monomer Allyl polyether 3-5 parts Initiator 1-3 parts 5-7 parts of the first solvent 3-5 parts of neutralizer.

5. An acrylic dispersion according to claim 4, characterized in that: The initiator includes one or more of azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate and benzoyl peroxide; and / or the first solvent includes one or more of propylene glycol methyl ether and dipropylene glycol ethyl ether.

6. An acrylic dispersion according to claim 1, characterized in that: It also includes a carboxyl unsaturated polymerizable monomer, wherein the carboxyl unsaturated polymerizable monomer is 7-10 parts; The carboxyl unsaturated polymerizable monomer includes one or more of acrylic acid and methacrylic acid.

7. The method for preparing an acrylic acid dispersion according to any one of claims 1 to 6, characterized in that: The following operations are included: The unsaturated polymerizable monomer, the carboxyl unsaturated polymerizable monomer, the acrylic acid crosslinking monomer and the allyl polyether are mixed with an initiator in a first solvent to react to obtain an acrylic acid polymer; A neutralizing agent is added to the acrylic polymer and dispersed in deionized water to obtain a modified acrylic dispersion.

8. A water-based transfer coating, characterized in that: The invention comprises the acrylic dispersion according to any one of claims 1 to 6, or the acrylic dispersion prepared by the preparation method of the acrylic dispersion according to claim 7.

9. A water-based transfer coating according to claim 8, characterized in that: Includes the following quality components: Modified acrylic dispersion 40-60 parts 15-25 parts of the second solvent Additives 0.1-1 parts 15-35 parts of deionized water.

10. A water-based transfer coating according to claim 9, characterized in that: The second solvent includes one or more of ethanol, isopropanol, n-butanol and dipropylene glycol dimethyl ether; and / or the auxiliary agent includes one or more of a leveling agent, a defoaming agent and a thickener.

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