Water-based emulsion oil-resistant coating agent, method for manufacturing paper, and paper having a coating layer comprising a water-based emulsion oil-resistant coating agent

Abstract

The present invention provides a water-based emulsion oil-resistant coating agent that is excellent in air permeability, oil resistance, and carbon neutrality by using a biologically-derived component as a main component. The present invention provides a water-based emulsion oil-resistant coating agent, a method for manufacturing paper characterized by applying the water-based emulsion oil-resistant coating agent, and paper having a coating layer containing the water-based emulsion oil-resistant coating agent, wherein the water-based emulsion oil-resistant coating agent contains component (a) that is hardened castor oil and / or rice wax, component (b) that is polyvinyl alcohol and / or casein, and water.

Description

Technical Field

[0001] This invention relates to an aqueous emulsion oil-resistant coating that improves carbon neutrality by using a biologically derived ingredient as the main component, a method for manufacturing paper, and paper using a coating layer of the aqueous emulsion oil-resistant coating. Background Technology

[0002] Paper or paperboard is widely used in food packaging materials, especially for foods containing large amounts of oil or grease, where oil-resistant paper or paperboard is used to prevent oil from penetrating the packaging paper. Previously, fluoropolymer-based oil-resistant agents were used to impart oil resistance to paper. However, there are concerns that heating these agents above 100°C can produce persistent fluorinated hydrocarbons, potentially causing adverse health or environmental effects. Therefore, a technology to replace fluoropolymer-based oil-resistant agents is being developed. As a technology that does not use fluoropolymer-based oil-resistant agents, known examples include paper products containing a coating of hydrophobic starch (Patent Document 1) or oil-resistant paper with a styrene-acrylic resin and a polyvinyl alcohol resin in the oil-resistant layer (Patent Document 2). However, these technologies ensure oil resistance through the formation of a coating film, and are therefore unsuitable for applications requiring both breathability and oil resistance. To improve both air permeability and oil resistance, an oil-resistant paper containing starch with hydrophobic groups and wax has been disclosed (Patent Document 3), which achieves both high air permeability and oil resistance. However, the air permeability has not reached a satisfactory level. Furthermore, in recent years, with the growing calls for building a circular society, there has been significant interest in so-called bio-based components with excellent carbon neutrality, aiming to reduce reliance on fossil fuels. However, it is difficult to meet the requirements of high air permeability and oil resistance while using bio-based raw materials, thus a search is underway for an oil-resistant agent that satisfies these requirements.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2002-069889

[0006] Patent Document 2: Japanese Patent Application Publication No. 2021-080591

[0007] Patent Document 3: Japanese Patent Application Publication No. 2013-237941 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] In view of the above, the object of the present invention is to provide an aqueous emulsion oil-resistant coating agent that can obtain oil-resistant paper with excellent carbon neutrality, high breathability, and oil resistance by using a biologically derived ingredient as the main component, a method for manufacturing paper coated with the aqueous emulsion oil-resistant coating agent, and paper having a coating layer containing the aqueous emulsion oil-resistant coating agent.

[0010] Technical means to solve the problem

[0011] That is, the present invention is

[0012] <1> An aqueous emulsion oil-resistant coating agent, comprising (a) as hardened castor oil and / or rice wax, (b) as polyvinyl alcohol and / or casein, and water,

[0013] <2> The water-based emulsion oil-resistant coating according to <1> is characterized in that it comprises component (a) and component (b) in a ratio of component (a) / component (b) of 100 / 1 to 20 by mass.

[0014] <3> The water-based emulsion oil-resistant coating according to <1> is characterized in that component (a) is hardened castor oil.

[0015] <4> The water-based emulsion oil-resistant coating according to <1> is characterized in that component (b) is casein.

[0016] <5> A method for manufacturing paper, characterized in that an aqueous emulsion oil-resistant coating according to any one of <1> to <4> is applied.

[0017] <6> A paper having a coating layer comprising an oil-resistant emulsion coating according to any one of <1> to <4>.

[0018] The effects of the invention

[0019] According to the present invention, an oil-resistant coating with high breathability, oil resistance, and high carbon neutrality and low environmental impact due to being mainly composed of hardened castor oil and / or rice wax as biological components can be obtained. Detailed Implementation

[0020] Hereinafter, embodiments of the present invention will be described in detail. However, this embodiment is one way of carrying out the present invention, and the present invention is not limited to this embodiment. In this specification, parts or percentages are used, but these are quality standards. Furthermore, numerical ranges indicated by "~" include the values ​​described before and after them.

[0021] The oil-resistant coating of the present invention contains (a) as a component of hardened castor oil and / or rice wax, (b) as a component of polyvinyl alcohol and / or casein, and water.

[0022] <As a component of hardened castor oil and / or rice wax (a)>

[0023] Component (a) is used to impart oil resistance and comprises hardened castor oil or rice wax or both. Component (a) is preferably hardened castor oil.

[0024] The hardened castor oil contained in component (a) is a hydrogenated form of castor oil, also known as hydrogenated castor oil. Castor oil is a type of vegetable oil extracted from the seeds of the castor bean (castor seed). Its main component is glycerol esters of ricinoleic acid, an unsaturated fatty acid, in addition to oleic acid, linoleic acid, and small amounts of glycerol esters of saturated fatty acids.

[0025] The rice wax contained in component (a) is a natural wax extracted from rice bran oil. It is also known as rice branwax. The main components of rice wax are esters of higher fatty acids and higher alcohols, in addition to free higher fatty acids, higher alcohols and small amounts of hydrocarbons.

[0026] <As a component of polyvinyl alcohol and / or casein (b)>

[0027] Component (b) enhances the emulsification or dispersion stability of component (a) and, from the viewpoints of reducing adverse effects on air permeability after coating on paper and the oil resistance of the dried coating film, needs to contain at least one selected from polyvinyl alcohol or casein. Casein is most preferred from the viewpoint of carbon neutrality.

[0028] The degree of saponification of the polyvinyl alcohol used in component (b) is preferably 70 mol% to 99 mol%, and more preferably 80 mol% to 90 mol%.

[0029] The ratio of component (a) to component (b) in the oil-resistant coating of the present invention, by weight, is preferably a ratio of component (a) / component (b) of 100 / 1 to 20. If the proportion of component (b) is less than 1, the emulsification stability of component (a) may be insufficient; if the proportion of component (b) is more than 20, the viscosity of the coating liquid may become too high, which may hinder the coating adaptability.

[0030] <Other Waxes>

[0031] In the oil-resistant coating of the present invention, waxes other than component (a) may be used within a range that does not deteriorate its breathability and oil resistance.

[0032] Waxes other than component (a) may include: plant-based waxes other than rice wax, such as wood wax, lacquer wax, carnauba wax, or candelilla wax; animal-based waxes such as beeswax, shellac wax, or lanolin; plant-based hardened oils obtained by hardening (hydrogenating) vegetable oils other than castor oil, such as soybean oil, rapeseed oil, palm oil, coconut oil, or rice oil; animal-based hardened oils obtained by hardening (hydrogenating) tallow or lard; mineral-based waxes such as lignite wax or ozogeralite; petroleum-based waxes such as paraffin wax and microcrystalline wax; Fischer-Tropsch wax; polyethylene wax; fatty acid ester waxes; or synthetic waxes such as fatty acid amides. One or more of these may be used in combination. From the viewpoint of carbon neutrality, it is preferable to use both biologically derived plant-based waxes and animal-based waxes.

[0033] <Other Emulsifiers and Dispersants>

[0034] In the oil-resistant coating of the present invention, in addition to component (b), other nonionic, anionic, cationic, or amphoteric emulsifying and dispersing agents may also be used. To avoid deterioration of its effectiveness or stability, the other nonionic, anionic, cationic, or amphoteric emulsifying and dispersing agents are preferably in the range of 0 to 10 parts by mass relative to 100 parts by mass of the total mass of component (a).

[0035] Examples of nonionic emulsifying and dispersing agents include: polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, glycerol fatty acid esters, propylene glycol fatty acid esters, polyoxyethylene alkylphenyl ethers, polyoxyethylene polycyclic phenyl ethers, polyoxyethylene alkylene alkyl ethers, polyoxyethylene sorbitan esters, polyoxyethylene sorbitol fatty acid esters, sucrose fatty acid esters, polyoxyethylene hardened castor oil, and alkyl imidazoline derivatives. Examples of anionic emulsifying and dispersing agents include: sodium alkylbenzene sulfonate, alkyl ammonium sulfate or dialkyl sulfosuccinate, styrene-maleic anhydride copolymers, α-olefin-maleic anhydride copolymers, diisobutylene-maleic anhydride copolymers, isobutylene-maleic anhydride copolymers, styrene-acrylic acid polymeric emulsifying and dispersing agents, acrylic acid polymeric emulsifying and dispersing agents, and other anionic synthetic emulsifying and dispersing agents; surfactants, sophorolipids, shellac, rosin, stearic acid or palmitic acid and other higher fatty acids and their salts, and other anionic modified natural emulsifying and dispersing agents; carboxymethyl cellulose, octenyl succinic anhydride modified starch, oxidized starch, hydroxypropyl xanthan gum, sulfonated castor oil, and other anionic modified natural emulsifying and dispersing agents. Examples of cationic emulsifying and dispersing agents include: alkyltrimethylammonium chloride, dialkylammonium chloride, benzyl ammonium chloride and other cationic surfactants; salts of glucosamine polysaccharides or cationic modifiers of starch, cellulose, and polyvinyl alcohol. Examples of amphoteric emulsifying dispersants include: alkyl dimethylaminoacetic acid betaine, or sodium monoalkylaminodiacetic acid, and other amphoteric synthetic low-molecular-weight emulsifying dispersants; and lecithin (including hydrides and hydroxides), and other amphoteric natural low-molecular-weight emulsifying dispersants. One or more of these can be used in combination. Among these, sulfonated castor oil and palmitic acid are preferred.

[0036] <Other Additives>

[0037] In the oil-resistant coating of the present invention, in addition to the components (a) and (b) mentioned above, various additives commonly used in coatings, such as viscosity modifiers, defoamers, preservatives, leveling agents, dyes, surface tension modifiers, lubricants, anti-blocking agents, antioxidants, and ultraviolet absorbers, may be added within a range that does not deteriorate its air permeability and oil resistance.

[0038] <Emulsification Methods>

[0039] There are no particular limitations on the method for forming the emulsion of the oil-resistant coating of the present invention, and conventionally known methods can be applied. For example, known methods such as: adding component (a) to an aqueous solution of component (b) and stirring at high temperature; solvent method in which component (a) is dissolved in a solvent, component (b) and water are added, followed by high-pressure emulsification and removal of the solvent by distillation; phase inversion emulsification method in which an aqueous solution of component (b) is added dropwise to the molten component (a) and the emulsion is changed from an oil-in-water droplet to a water-in-oil droplet; high-pressure emulsification method in which the components are mixed under high temperature and pressure and then high-pressure emulsified; and ultrasonic emulsification method. Among these, high-pressure emulsification method is preferred for forming the emulsion. There are no particular limitations on the timing of adding component (b). The total amount of component (b) can be added before the step of emulsifying component (a), or a portion can be added in batches after the emulsification of component (a).

[0040] The solid content of the oil-resistant coating of the present invention is preferably 10% or more and 55% or less, and more preferably 15% or more and 50% or less. When the solid content exceeds 55%, it tends to thicken over time, and the concentration of solid content on the liquid surface increases during storage, which easily leads to the formation of coagulations (skin formation). When it is below 10%, it is uneconomical because the effective ingredient is less.

[0041] Furthermore, the so-called solid component in this invention is the percentage of the residual mass of the water-based emulsion oil-resistant coating after heating and drying at 150°C for 20 minutes relative to the mass before heating.

[0042] As a representative application of the water-based emulsion oil-resistant coating of the present invention, it can be exemplified by coating it on paper.

[0043] <Paper>

[0044] The paper used in this application refers to paper and / or paperboard. Any ordinary paper or paperboard whose main component is biodegradable pulp can be used without particular restriction. Examples include: woodfree paper, pure white toilet paper, unbleached or bleached kraft paper, cellophane, coated paper, linerboard, paper tube linerboard, white chipboard, and grey chipboard paper.

[0045] <Method for manufacturing paper characterized by applying the oil-resistant coating of the present invention>

[0046] The method of applying the oil-resistant coating of the present invention to paper can be used without limitation as long as it is a known method. Examples include: rod coating, blade coating, die coating, curtain coating, air knife coating, spraying, gravure coating, flexographic coating, size press coating, etc.

[0047] Furthermore, the oil-resistant coating of the present invention is suitable for both single-layer and multi-layer coatings, and thus for both single-sided and double-sided coatings. The application amount of the oil-resistant coating of the present invention is not particularly limited; however, from the viewpoint of oil resistance and cost, 1 g / m² is preferred. 2 ~10g / m 2 .

[0048] To impart heat-sealing properties to the coating layer, the oil-resistant coating agent of the present invention can also be used in conjunction with various heat-sealing agents. Examples of heat-sealing agents include: acrylic resins, polyester resins, vinyl chloroacetate resins, thermosetting urethane resins, and other thermosetting resins.

[0049] The oil-resistant coating and heat sealant of the present invention can be mixed and applied together, or they can be applied separately in multiple layers. In this case, the application order of the oil-resistant coating and heat sealant can be prioritized. Furthermore, the heat sealant can also be applied to the side of the paper coated with the oil-resistant layer of the present invention opposite to the coated surface.

[0050] Between the paper and the coating layer containing the oil-resistant coating of the present invention, a coating layer for controlling liquid absorption or a coating layer for filling the unevenness of the paper surface to make it smooth may also be provided.

[0051] Drying methods for wet coatings can be used without restriction, as long as they are known. Examples include: cylinder heating, steam heating, hot air heating, infrared heating, and high-frequency heating.

[0052] Example

[0053] The following is a detailed description based on embodiments of the present invention, but the present invention is not limited to these embodiments.

[0054] (Example of casein dissolution)

[0055] In a four-necked separable flask including a heating device, a stirring device, a cooling pipe, and a thermometer, 200 parts of casein (manufactured by Fujifilm and Kojun Pharmaceutical Co., Ltd.), 15 parts of 28% ammonia water, and 785 parts of water were added. The mixture was heated to 85°C with stirring and dissolved for 20 minutes while maintaining the temperature, thereby obtaining a 20% casein solution (casein liquid).

[0056] <Preparation of water-based emulsion oil-resistant coating>

[0057] (Oil-resistant coating 1)

[0058] In a four-necked detachable flask including a heating device, stirring device, cooling pipe, and thermometer, 262 parts of water and 14 parts of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: 5-88) were added. The mixture was heated to 90°C with stirring and stirred for 60 minutes while maintaining the temperature to dissolve the polyvinyl alcohol. Then, 200 parts of hardened castor oil (manufactured by Ito Oil Co., Ltd., product name: Hardened Castor Oil A) were added, and the mixture was heated to 95°C with stirring and stirred for 10 minutes while maintaining the temperature to form an emulsion. Next, the emulsion was subjected to high-pressure emulsification (emulsification pressure 200 kgf / cm²) using a Manton Gaulin emulsifier. 2 After preparing a uniform emulsion, it is mixed with 237 parts of water under stirring, and then cooled until the temperature is below 40°C to obtain an oil-resistant coating 1 with a solid content of 30%.

[0059] (Oil-resistant coating 2-4, oil-resistant coating 8-9, oil-resistant coating 11-14)

[0060] Except for changing the types, weight ratios, and solid components of components (a) and (b) as described in Table 1, oil-resistant coatings 2 to 4, 8 to 9, and 11 to 14 are obtained in the same manner as oil-resistant coating 1.

[0061] (Oil-resistant coating 5)

[0062] In a four-necked separable flask including a heating device, a stirring device, a cooling pipe, and a thermometer, 270 parts of water, 30 parts of a 20% casein solution (casein liquid), and 6 parts of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: 5-88) were added. The mixture was heated to 90°C with stirring and stirred for 60 minutes at the same temperature to dissolve the polyvinyl alcohol. Then, 200 parts of hardened castor oil (manufactured by Ito Oil Co., Ltd., product name: hardened castor oil A) were added, and the mixture was heated to 95°C with stirring and stirred for 10 minutes at the same temperature to form an emulsion. Next, the emulsion was subjected to high-pressure emulsification (emulsification pressure 200 kgf / cm²) using a Manton Gaulin emulsifier. 2 After preparing a uniform emulsion, 201 parts of water were added while stirring. The mixture was then cooled until the temperature dropped below 40°C to obtain an oil-resistant coating with a solid content of 30%.

[0063] (Oil-resistant coating 6-7, oil-resistant coating 10)

[0064] Except for changing the types and weights of components (a) and (b) as described in Table 1, oil-resistant coatings 6 to 7 and 10 are obtained in the same manner as oil-resistant coating 5.

[0065] (Oil-resistant coating 15)

[0066] In addition to changing the types and weights of components (a) and (b) as described in Table 1, we attempted to adjust the oil-resistant coating 15 in the same manner as in the case of oil-resistant coating 1, but the emulsification was poor and it was difficult to obtain a stable emulsion.

[0067] (Oil-resistant coating 16)

[0068] In a four-necked detachable flask including a heating device, stirring device, cooling pipe, and thermometer, 270 parts of water and 6 parts of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: 5-88) were added. The mixture was heated to 90°C with stirring and stirred for 60 minutes while maintaining the temperature to dissolve the polyvinyl alcohol. Then, 200 parts of hardened castor oil (manufactured by Ito Oil Co., Ltd., product name: Hardened Castor Oil A) were added, and the mixture was heated to 95°C with stirring and stirred for 10 minutes while maintaining the temperature to form an emulsion. Next, the emulsion was subjected to high-pressure emulsification (emulsification pressure 200 kgf / cm²) using a Manton Gaulin emulsifier. 2 After preparing a uniform emulsion, it is added to a mixture of 201 parts water and 30 parts casein solution (casein liquid) with a concentration of 20% while stirring. The mixture is then cooled until the temperature drops below 40°C to obtain an oil-resistant coating 16 with a solid content of 30%.

[0069] (Oil-resistant coating 17)

[0070] 100g of commercially available oxidized corn starch (manufactured by Nippon Food Chemical Co., Ltd., product name: MS#3800) (10% solid content) after gelatinization at 90°C for 30 minutes was mixed with 17.8g of oil-resistant coating agent 13 to obtain oil-resistant coating agent 17 with 13% solid content.

[0071] [Table 1]

[0072]

[0073] PVA: Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name 5-88)

[0074] Oxidized starch: Oxidized corn starch (manufactured by Nippon Food Chemical Co., Ltd., product name: MS#3800)

[0075] CMC: Sodium carboxymethyl cellulose (manufactured by Daicel Inc., product name CMC Daicel 1110)

[0076] Rice wax: Manufactured by BOSO Oils & Fats Co., Ltd., product name: Rice Wax SS-2

[0077] Paraffin wax: Manufactured by Nippon Reiki Co., Ltd., product name Paraffin Wax-135; Sulfonated castor oil: Manufactured by Takemoto Oils Co., Ltd., product name Sulfonated castor oil K.

[0078] Palmitic acid: Manufactured by Pure Chemical Co., Ltd., product name: palmitic acid

[0079] Brazilian carnauba wax: Manufactured by Shan Gui Industry Co., Ltd., product name: Brazilian carnauba wax (No. 1)

[0080] <Application of oil-resistant coatings>

[0081] The application conditions for oil-resistant coatings and the determination or evaluation methods for each evaluation item shall be carried out in accordance with the following methods.

[0082] (Coated base paper)

[0083] Single-sided bleached kraft paper: basis weight 50g / m² 2

[0084] (Apply as a coating)

[0085] To ensure that the adhesion of each oil-resistant coating is 7 g / m² based on solid content 2 The coating was applied to the non-gloss surface of the base paper using a rod coater (rod No. 14) and dried at 110°C for 0.5 minutes using a warm air dryer. Subsequently, after 24 hours of conditioning at 23°C and 50% RH, the grease barrier coefficient (Kit) value, an indicator of oil resistance, was measured, and the air permeability, an indicator of air permeability, was measured.

[0086] (Kit value): Evaluated according to Japan Pulp and Paper Manufacturers Association (JAPAN TAPPI) No. 41. The higher the value, the better the oil resistance. In terms of practicality for use in a wide range of applications, a Kit value of 5 or higher is ideal.

[0087] (Air permeability) was measured using a Parker Print Surf Tester (PPS) manufactured by Mesmer. A lower value indicates better air permeability. For applications where air permeability is required, an air permeability of 250 seconds or less is suitable.

[0088] (Example 1)

[0089] Oil-resistant coated paper was obtained by coating single-sided bleached kraft paper with oil-resistant agent 1 under the conditions described and then drying it. After conditioning, the Kit value and air permeability were measured. The results are shown in Table 2.

[0090] (Examples 2 to 11, Comparative Examples 3 to 4)

[0091] Except for the changes to the oil-resistant coating as shown in Table 2, oil-resistant coated paper was obtained in the same manner as in Example 1. Furthermore, the Kit value and air permeability were measured in the same manner as in Example 1. These results are shown in Table 2.

[0092] (Comparative Example 1, Comparative Example 2)

[0093] Except for changing the oil-resistant coating as shown in Table 2, and changing the rod No. of the rod coater from 14 to 18 during coating, the oil-resistant coated paper was obtained in the same manner as in Example 1. Furthermore, the Kit value and air permeability were measured in the same manner as in Example 1. These results are shown in Table 2.

[0094] (Comparative Example 5)

[0095] Because it is impossible to prepare a coating solution for oil-resistant coatings, coating evaluation cannot be performed.

[0096] (Comparative Example 6)

[0097] Except for changing the oil-resistant coating as shown in Table 2, and changing the rod No. of the rod coater from 14 to 32 during coating, the oil-resistant coated paper was obtained in the same manner as in Example 1. Furthermore, the Kit value and air permeability were measured in the same manner as in Example 1. These results are shown in Table 2.

[0098] [Table 2]

[0099] Example 1 Oil-resistant coating 1 5 110 Example 2 Oil-resistant coating 2 5 88 Example 3 Oil-resistant coating 3 6 108 Example 4 Oil-resistant coating 4 5 140 Example 5 Oil-resistant coating 5 6 120 Example 6 Oil-resistant coating 6 6 113 Example 7 Oil-resistant coating 7 6 102 Example 8 Oil-resistant coating 8 5 128 Example 9 Oil-resistant coating 9 6 120 Example 10 Oil-resistant coating 10 5 135 Example 11 Oil-resistant coating 16 5 129 Comparative Example 1 Oil-resistant coating 11 3 56 Comparative Example 2 Oil-resistant coating 12 3 68 Comparative Example 3 Oil-resistant coating 13 3 125 Comparative Example 4 Oil-resistant coating 14 4 120 Comparative Example 5 Oil-resistant coating 15 - - Comparative Example 6 Oil-resistant coating 17 5 2460

[0100] Comparing Examples 1 to 11, which meet the conditions of the present invention, with Comparative Examples 1 to 5, which do not meet the conditions of the present invention, it can be seen that the paper exhibits excellent oil resistance and high air permeability when coated with the aqueous emulsion oil-resistant coating used in Examples 1 to 11. Furthermore, it can be seen that, compared with Comparative Examples 3 and 4, which use paraffin containing fossil fuel-derived components, Examples 1, 3, and 8, which use biologically derived components corresponding to component (a), also show excellent oil resistance in carbon-neutral materials.

[0101] As can be seen, compared with Examples 1 to 10 of the present invention, Comparative Example 6, which was coated with a mixture of paraffin and starch prepared with reference to Example 1 disclosed in Japanese Patent Application Publication No. 2013-237941, has significantly poorer air permeability.

Claims

1. An aqueous emulsion oil-resistant coating containing component (a) as hardened castor oil and / or rice wax, component (b) as polyvinyl alcohol and / or casein, and water, comprising component (a) and component (b) in a mass ratio of component (a) / component (b) = 100 / 1 to 20.

2. The water-based emulsion oil-resistant coating according to claim 1, characterized in that, Component (a) is hardened castor oil.

3. The water-based emulsion oil-resistant coating agent according to claim 1, characterized in that, Component (b) is casein.

4. A method for manufacturing paper, characterized in that, Apply the water-based emulsion oil-resistant coating as described in any one of claims 1 to 3.

5. A paper having a coating layer comprising an aqueous emulsion oil-resistant coating as described in any one of claims 1 to 3.

Images