JPH06145612A - Undercoating agent for releasing paper - Google Patents

Abstract

PURPOSE:To obtain the subject undercoating agent having excellent applicability, adhesivity and recoverability and useful for label, seal, etc., by using a specific aqueous resin as a main component. CONSTITUTION:The objective undercoating agent contains, as a main component, an aqueous resin produced by the emulsion-polymerization of preferably 100 pts.wt. of a radically polymerizable monofunctional vinyl monomer such as alkyl (meth)acrylate in an aqueous solution containing preferably 5-900 pts.wt. of PVA in the presence of a reactive emulsifier having >=2 C-C double bonds in one molecule.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an undercoat agent for release paper. More specifically, the present invention relates to an undercoat agent for release paper, which contains a novel aqueous resin obtained by combining polyvinyl alcohol and microgel and is particularly suitable when a solvent type silicone resin is used as a release agent.

[0002]

2. Description of the Related Art Release paper is widely used in the field of adhesives for labels and seals, and the production amount thereof is increasing year by year. Such release papers have been manufactured mainly by a method of directly applying a release agent liquid such as a solvent-type or emulsion-type silicone resin onto a mount. However, such a method has a problem that the amount of the silicone resin used increases because the coating liquid penetrates into the mount. Therefore,
In recent years, in the production of release paper, in order to suppress the permeation of the coating liquid, a method in which polyethylene is first laminated on a mount and a solvent-type silicone resin is applied on the mount is becoming the mainstream.

However, due to resource and environmental problems, it has become necessary to recycle paper into recycled paper, so that the polyethylene-based release paper, which has poor recoverability, should be replaced with easily recoverable release paper. The Ministry of International Trade and Industry has issued notification instructions. As a method of making the release paper easily collectable, instead of laminating polyethylene on the backing paper, latexes such as SBR and acrylic emulsion as undercoat agents, and various water-soluble polymers such as polyvinyl alcohol and polyacrylamide are used. Although methods of applying to a mount have been studied, these methods are not sufficiently satisfactory in terms of performance, workability and the like. That is, latexes such as SBR and acrylic emulsion have excellent coatability, but have poor solvent resistance, so that there is a problem that the toluene solution penetrates into the mount when the toluene solution of the silicone resin is coated. On the other hand, water-soluble polymers have excellent solvent resistance,
Since solvent resistance correlates with molecular weight, it is generally necessary to use a high molecular weight water-soluble polymer (that is, a highly viscous water-soluble polymer aqueous solution), resulting in poor stability of the aqueous solution over time or high concentration coating. There is a problem that the work becomes difficult and the workability is poor. Further, the adhesion between the undercoating agent and the silicone resin is also an important factor, but some water-soluble polymers have inferior adhesion. Therefore, a water-soluble polymer having a good balance of coatability and adhesion is Not yet obtained.

[0004]

DISCLOSURE OF THE INVENTION The present invention is suitable for an easily recoverable release paper, and even when a solvent type silicone resin is coated on a backing paper, the silicone resin does not penetrate into the paper layer, and It is an object of the present invention to provide an undercoat agent for release paper, which is excellent in adhesiveness to silicone resin and coatability.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor has found that a specific reactive emulsifying agent is used and vinyl is used in an aqueous solution containing polyvinyl alcohol. The inventors have found that the use of a novel aqueous resin obtained by emulsion-polymerizing a monomer can provide an undercoating agent for release paper that can solve the above problems, and completed the present invention.

That is, according to the present invention, a reactive emulsifier having two or more carbon-carbon double bonds in a molecule is used as an emulsifier, and a radical-polymerizable monofunctional compound is used in an aqueous solution containing polyvinyl alcohol. An undercoat agent for release paper, which contains an aqueous resin obtained by emulsion polymerization of a vinyl monomer as a main component, and a reactivity having one or more carbon-carbon double bonds in the molecule as an emulsifier. An aqueous solution obtained by emulsion-polymerizing a radically polymerizable monofunctional vinyl monomer and a polyfunctional vinyl monomer in an aqueous solution containing polyvinyl alcohol using an emulsifier, The present invention relates to an undercoat agent for release paper.

The constitution of the aqueous resin which is the main component of the undercoat agent for release paper of the present invention will be described below.

The polyvinyl alcohol used in the production of the aqueous resin of the present invention is not particularly limited as long as it is water-soluble, but usually, the degree of polymerization is about 200 to 2500, and the degree of saponification is 75% to 100%. Saponified or fully saponified is preferred. Further, a modified polyvinyl alcohol having a functional group such as a carboxyl group, an acetoacetyl group, an acetal group or the like can be used as well. Further, since polyvinyl alcohol affects the solvent resistance of the obtained undercoat agent, the amount used is appropriately determined in consideration of these properties. That is, the amount of polyvinyl alcohol used is usually about 5 to 900 parts by weight, preferably 40 to 250 parts by weight, based on 100 parts by weight of the total amount of vinyl monomers. If it is less than 5 parts by weight, the solvent resistance of the obtained undercoating agent becomes poor, and if it exceeds 900 parts by weight, the stability of the aqueous resin solution as an undercoating agent for release paper obtained at the time becomes poor, which is not preferable.

As the radically polymerizable monofunctional vinyl monomer of the present invention, it is preferable to use (meth) acrylic acid alkyl ester and / or styrene compound. The (meth) acrylic acid alkyl ester preferably has an alkyl group having 1 to 18 carbon atoms, and examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, ( Examples thereof include iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and stearyl (meth) acrylate. Examples of styrene compounds include styrene, α-methylstyrene, vinyltoluene and the like. These monofunctional vinyl monomers may be used either individually or in combination of two or more. Among them, since they do not cause side reactions during radical polymerization, they are used as methacrylic acid alkyl ester and / or styrene. Compounds of the type are preferred.

The (meth) acrylic acid alkyl ester and / or the styrene compound are various anionic monofunctional vinyl monomers, cationic monofunctional vinyl monomers, and nonionic monofunctional vinyl monomers other than the above. It can be used in combination with a monomer. As the anionic monofunctional vinyl monomer, acrylic acid, methacrylic acid, monocarboxylic acid such as crotonic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid,
Dicarboxylic acids such as muconic acid, vinyl sulfonic acids, styrene sulfonic acids, organic sulfonic acids such as 2-acrylamido-2-methylpropane sulfonic acid, phosphoric acid vinyl monomers such as 2- (meth) acryloyloxyethyl acid phosphate, and Examples thereof include sodium salts and potassium salts of these various organic acids. Dimethylaminoethyl (meth) as a cationic monofunctional vinyl monomer
Acrylic, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, diethylaminopropyl (meth) acrylamide and other vinyl monomers having a tertiary amino group or their inorganic or organic acids such as hydrochloric acid, sulfuric acid and acetic acid. salts,
Alternatively, a vinyl monomer containing a quaternary ammonium salt obtained by the reaction of the tertiary amino group-containing vinyl monomer with a quaternizing agent such as methyl chloride, benzyl chloride, dimethylsulfate, epichlorohydrin, etc. may be mentioned. Nonionic monofunctional vinyl monomers include (meth) acrylamide, (meth) acrylonitrile,
Hydroxy group-containing (meth) acrylates such as vinyl acetate, methyl vinyl ether, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, glycidyl (Meth) acrylate, N-methylol (meth) acrylamide, urethane acrylates,
Typical examples thereof include phosphoric acid ester vinyl monomers such as diphenyl-2 (meth) acryloyloxyphosphate.

Further, in the present invention, in addition to the monofunctional vinyl monomer exemplified above, a polyfunctional vinyl monomer can be used. For example, as the bifunctional vinyl monomer, di (meth) acrylates such as ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate and triethylene glycol di (meth) acrylate, methylenebis (meth) acrylamide, ethylenebis (Meth) acrylamide,
Bis (meth) acrylamides such as hexamethylene bis (meth) acrylamide, divinyl esters such as divinyl adipate and divinyl sebacate, allyl methacrylate, diallyl amine, diallyl dimethyl ammonium, diallyl phthalate, diallyl chlorendate,
Examples include divinylbenzene. Further, as the trifunctional monomer, 1,3,5-triacryloylhexahydro-S-triazine, triallyl isocyanurate,
Triallylamine, triallyl trimellitate, N, N
Examples of the tetrafunctional vinyl monomer include tetramethylolmethane tetraacrylate, tetraallylpyromellitate, N, N,
N ', N'-tetraallyl-1,4-diaminobutane,
Examples thereof include tetraallylamine salt and tetraallyloxyethane.

When a polyfunctional vinyl monomer is used, its amount is about 5 parts by weight or less, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the total of the monofunctional vinyl monomers. is there. When the amount of the polyfunctional vinyl monomer exceeds 5 parts by weight, aggregation occurs and it becomes difficult to obtain a high-concentration aqueous resin solution, which is not preferable.

When only the monofunctional vinyl monomer is used in the production of the aqueous resin of the present invention, the emulsion polymerization is carried out in the presence of a reactive emulsifier having two or more carbon-carbon double bonds in the molecule. It is indispensable to do.

The reactive emulsifier having a carbon-carbon double bond in the molecule is not particularly limited and various reactive emulsifiers can be appropriately selected and used. Examples of the carbon-carbon double bond include functional groups such as (meth) allyl group, 1-propenyl group, 2-methyl-1-propenyl group, vinyl group, isopropenyl group, and (meth) acryloyl group. To be Specifically, a sulfosuccinate ester salt of polyoxyethylene alkyl ether having at least two functional groups in the molecule, a sulfuric acid ester salt of polyoxyethylene alkyl ether having at least two functional groups in the molecule, and the functional group Examples thereof include sulfosuccinic acid ester salts of polyoxyethylene alkylphenyl ethers having at least two in the molecule and sulfuric acid ester salts of polyoxyethylene alkylphenyl ethers having at least two of the above functional groups in the molecule. Furthermore, an acidic phosphoric acid (meth) acrylate dispersant having at least two functional groups in the molecule, and an oligoester (meth) having at least two functional groups in the molecule
Examples thereof include phosphoric acid esters of acrylates or alkali salts thereof, and oligoester poly (meth) acrylates of polyalkylene glycol derivatives having a hydrophilic alkylene oxide group having at least two functional groups in the molecule. These commercial products include (trade name KAYAMER PM-2, manufactured by Nippon Kayaku Co., Ltd.), (trade name New Frontier A-229).
E, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., (trade name: New Frontier N-250Z, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and the like are typical examples. Among these, reactive emulsifiers having a (meth) acryloyl group as a carbon-carbon double bond are preferable.

Further, the reactive emulsifier having two or more carbon-carbon double bonds in the molecule has one carbon-carbon double bond.
It may be a mixture containing reactive emulsifiers. However, the reactive emulsifier having one carbon-carbon double bond is preferably about 60% by weight or less based on the total amount of the reactive emulsifiers.

Reactive emulsifiers having one carbon-carbon double bond are disclosed in JP-A-63-23725, JP-A-63-240931 and JP-A-62-104802.
Or those listed in the official gazette (brand name KAYAMER PM
-1, Nippon Kayaku Co., Ltd., (brand name SE-10N, Asahi Denka Kogyo KK), (Brand name NE-10, Asahi Denka Kogyo KK), (Brand name NE-20) , Asahi Denka Co., Ltd.
Manufactured), (trade name NE-30, manufactured by Asahi Denka Kogyo Co., Ltd.),
(Brand name New Frontier N-117E, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), (Brand name Aqualon RN-20, made by Dai-ichi Kogyo Seiyaku Co., Ltd.), (Brand name Aqualon HS-10, Dai-ichi Kogyo Seiyaku ( Co., Ltd.), (trade name: Eminor JS-2,
Representative examples thereof include commercial products such as Sanyo Kasei Co., Ltd., (trade name: Latemur S-120, manufactured by Kao Corporation), (trade name: Latemur S-180, manufactured by Kao Corporation).
The carbon-carbon double bond of the reactive emulsifier having one carbon-carbon double bond also preferably has a (meth) acryloyl group.

When a monofunctional vinyl monomer and a polyfunctional vinyl monomer are used in the production of the aqueous resin of the present invention, a reaction having one or more carbon-carbon double bonds in the molecule. It is essential to carry out emulsion polymerization in the presence of a strong emulsifier. Examples of such reactive emulsifiers include the same reactive emulsifiers having two or more carbon-carbon double bonds and the reactive emulsifiers having one carbon-carbon double bond.

The reactive emulsifier may be used in combination with a known anionic emulsifier or nonionic emulsifier to the extent that it does not adversely affect the performance of the undercoat agent for release paper comprising the novel aqueous resin of the present invention. Good. Examples of the anionic emulsifier include long-chain sodium α-olefin sulfonate, alkyldiphenyloxyethylene alkylaryl ether sulfate ester salt and the like, and examples of the nonionic emulsifier include polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene block polymer, Examples thereof include polyoxyethylene alkyl phenyl ether.

The amount of the reactive emulsifier used is usually 1 to 30 with respect to 100 parts by weight of the total amount of the monofunctional vinyl monomers, or when using the polyfunctional vinyl monomers, the total amount thereof. Parts by weight, preferably 3 to 1
5 parts by weight is preferable. If it is less than 1 part by weight, aggregates are generated during the polymerization, which is not preferable. If it exceeds 30 parts by weight, the solvent resistance of the undercoating agent for release paper may be poor, or the polymerization stability may be poor and gelation may occur with the progress of polymerization, which is not preferable.

Next, the method for producing the aqueous resin of the present invention will be described. The novel aqueous resin production method of the present invention may be carried out by a known emulsion polymerization method. For example, the polyvinyl alcohol and water are charged into a predetermined reaction vessel and dissolved while heating, then the reactive emulsifier and the vinyl monomer are charged, and after emulsification, a radical polymerization initiator is added, and the method is heated under stirring. You can follow. In addition,
The dropping method of the vinyl monomer may be either a batch dropping method or a divided dropping method. The solid content concentration of the reaction system is usually about 10 to 50% by weight, preferably 15 to 30% by weight.
Is.

The pH during polymerization is usually in the range of about 3-9. The reaction temperature may be in the temperature range for activating the polymerization catalyst, and is usually about 40 to 90 ° C, preferably 50 to 80 ° C, and the reaction time is usually 30 minutes to 2
Time is good.

Examples of the radical polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, hydrogen peroxide, water-soluble radical polymerization initiators such as aqueous azo initiators, and the above-mentioned persulfates. Examples thereof include redox-based polymerization initiators in the form of a combination with a reducing agent such as sodium hydrogen sulfite and sodium thiosulfate. Usually, the amount of the initiator used is 0.0 with respect to the total amount of the vinyl monomers.
It is about 5 to 5% by weight, preferably 0.1 to 3% by weight.

During the reaction, a transition metal ion may be added as a polymerization accelerator. Examples of the transition metal ion include copper ion, and the transition metal ion concentration in the reaction system is usually 1.0 × 10 ^{−8 to} 1.0 × 10 ⁻³ mol / mol.
It is recommended to use it so that it is about 1 liter.

In this way, the average particle size is usually 10 to 10.
An aqueous resin solution containing fine particles of about 300 nm is obtained. When the aqueous resin solution is used as an undercoat agent for release paper, the nonvolatile content is usually 10 to 30.
Viscosity is about 100-1000 at 25% by weight (25 ° C)
It is better to adjust to.

When applying the undercoating agent for release paper of the present invention to a mount, a usual coating method using a wire bar, a blade coater, an air knife coater, a roll coater or the like may be adopted. Further, the drying may be performed using a known drying device such as an oven and a drum dryer, and may further be subjected to a calendering treatment and adjusted so as to have a desired smoothness.

[0026]

EFFECTS OF THE INVENTION According to the present invention, even when a release agent (for example, a toluene solution of a silicone resin) is applied to a backing paper, the release agent is not absorbed in the paper layer and the coating property is excellent. Moreover, it is possible to provide an undercoat agent for release paper, which has excellent adhesion to silicone resin. Furthermore, the release paper obtained by using the undercoating agent for release paper is easy to collect and can contribute to resource saving and environmental problems.

[0027]

EXAMPLES The present invention will be described more specifically below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In addition,% in each example is based on weight unless otherwise specified.

Example 1 In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen gas inlet tube, a monomer dropping funnel and a thermometer, 50 g of completely saponified polyvinyl alcohol (hereinafter referred to as PVA110) having a degree of polymerization of 1100 and 500 g of water. Was charged, and the mixture was stirred with heating to dissolve it into an aqueous solution. This aqueous solution at 40 ° C
After cooling to room temperature, an aqueous solution of copper sulfate was added so that the concentration in the system would be 2.5 × 10 ⁻⁶ mol / liter. Then, an oligoester-based reactive emulsifier having two or more carbon-carbon double bonds in the molecule (trade name: New Frontier A-229)
6.5 g of E, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. was charged and 25% aqueous ammonia was added to adjust the pH to 5 and dissolve.
Then, 50 g of a mixed monomer consisting of butyl methacrylate, cyclohexyl methacrylate, and glycidyl methacrylate (weight mixing ratio was 59: 39: 2 in order) was added and emulsified at a constant speed (250 ± 10 rpm). The temperature is raised under a nitrogen stream, and a redox type initiator (concentration in the system: 6.0 × 10 ⁻³ mol / liter) consisting of equimolar amounts of potassium persulfate and sodium thiosulfate is added at 60 ° C. to start polymerization. It was The reaction was carried out for 60 minutes so that the polymerization temperature did not exceed 80 ° C. to obtain an aqueous resin solution containing transparent fine particles.
The non-volatile content of the obtained aqueous resin solution is 15.1%, pH
The viscosity at 4.2 and 25 ° C. was 450 cps.

Example 2 In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen gas introduction tube, a monomer dropping funnel and a thermometer, 50 g of partially saponified polyvinyl alcohol (hereinafter referred to as PVA210) having a degree of polymerization of 1100 and 500 g of water. Was charged, and the mixture was stirred with heating to dissolve it into an aqueous solution. This aqueous solution at 40 ° C
After cooling to room temperature, an aqueous solution of copper sulfate was added so that the concentration in the system would be 2.5 × 10 ⁻⁵ mol / liter. Then, an oligoester-based reactive emulsifier having two or more carbon-carbon double bonds in the molecule (trade name: New Frontier A-229)
5 g of E, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. was charged and 25% aqueous ammonia was added to adjust the pH to 5 and dissolve. Next, 50 g of a mixed monomer composed of ethyl methacrylate, styrene, and 2-hydroxyethyl acrylate (mixing ratio by weight: 57: 37: 6) was added at a constant rate (250 ± 1).
It was emulsified at 0 rpm. 60 ° C by raising the temperature under a nitrogen stream
Then, potassium persulfate and sodium thiosulfate were added so that the concentration in the system would be 2.5 × 10 ⁻³ mol / liter to initiate polymerization. 60 so that the polymerization temperature does not exceed 80 ℃
A partial reaction was carried out to obtain an aqueous resin solution containing transparent fine particles. The nonvolatile content of the obtained aqueous resin solution was 15.1%, p
The viscosity at H4.2 and 25 ° C was 250 cps.

Example 3 In Example 1, the reactive emulsifier was traded under the trade name Aqualon H.
S-10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., a sulfate ester reactive emulsifier having one carbon-carbon double bond in the molecule)
3.0 g of phosphoric acid-based emulsifier (trade name: H-3051, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 1.0
transparency was performed in the same manner as in Example 1 except that 2 g of ethyl hexyl methacrylate, methyl methacrylate, acrylonitrile (the mixing ratio by weight was 55: 45: 5) and 0.25 g of divinylbenzene were used as mixed monomers. An aqueous resin solution containing fine particles was obtained. The nonvolatile content of the obtained aqueous resin solution is 15.1%, pH 4.8, 25
The viscosity at ° C was 430 cps.

Comparative Example 1 A reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen gas inlet tube, a monomer dropping funnel and a thermometer was charged with ion-exchanged water 10
0 g of a copper sulfate aqueous solution was added so that the concentration in the system would be 2.5 × 10 ⁻⁵ mol / liter. Then, 20 g of an oligoester-based reactive emulsifier having two or more carbon-carbon double bonds in the molecule (trade name New Frontier A-229E, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was charged and 25% concentration of ammonia water was added. In addition, the pH was adjusted to 4 and dissolved. Then, 40 g of a mixed monomer consisting of butyl methacrylate, cyclohexyl methacrylate, and glycidyl methacrylate (weight mixing ratio is 59: 39: 2 in order) was added at a constant rate (25
It was emulsified at 0 ± 10 rpm. A redox type initiator (concentration in the system: 6.0 x
10 ⁻³ mol / liter) was added to initiate polymerization. Then, polymerization was carried out while continuously dropping 260 g of the mixed monomer. The heat generated by the polymerization heat is controlled by adjusting the dropping rate of the monomer and cooling by blowing air.
The reaction was carried out for 60 minutes so that the temperature did not exceed 0 ° C. to obtain an aqueous resin solution containing transparent fine particles. The resulting aqueous resin solution had a nonvolatile content of 42.5%, a pH of 3.2, and a viscosity at 25 ° C. of 250 cps.

Comparative Example 2 A reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen gas inlet tube, a monomer dropping funnel and a thermometer was charged with ion-exchanged water 25.
0 g, dialkyl sulfosuccinic acid ester soda salt (trade name Neocor P, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., nonvolatile content 7
6.5% (5%) was charged and dissolved. 80 ° C under nitrogen stream
The temperature is raised to 100, and a mixed monomer consisting of butyl methacrylate, cyclohexyl methacrylate and glycidyl methacrylate (weight mixing ratio is 59: 39: 2 in order) 100
g and an aqueous potassium persulfate solution were continuously added dropwise to carry out polymerization. The reaction was carried out for 90 minutes so that the polymerization temperature did not exceed 80 ° C. to obtain an aqueous resin solution. The resulting aqueous resin solution had a nonvolatile content of 25.5%, a pH of 5.2, and a viscosity at 25 ° C. of 50 cps.

(Performance Evaluation) The aqueous resin solutions obtained in Examples 1 to 3 and Comparative Examples 1 and 2, and a polymerization degree of 1700.
Completely saponified polyvinyl alcohol (hereinafter PVA117
Is prepared at the coating concentration shown in Table 1, and then applied and dried on PPC paper so that the solid content adhesion amount becomes 5 g / m ^2, and further calendered (50 Kg / c).
m) was applied. Using this as a sample, a performance test was conducted according to the following method. The results are shown in Table 1.

(Smoothness) The smoothness was measured by an Oken type air permeability smoothness tester.

(Solvent resistance) Toluene in which a dye was dissolved was applied to the coated surface with a paintbrush, and the presence or absence of strikethrough was observed. ◯: No strikethrough. △: There are strikethroughs in places. X: Many strikethroughs.

(Silicone adhesion) A silicone resin (KS776A manufactured by Shin-Etsu Chemical Co., Ltd.) diluted with toluene to a concentration of 5% was mixed with 1% of a curing catalyst (CAT-PL-8 manufactured by Shin-Etsu Chemical Co., Ltd.) (KS766A). (Based on the solid content) and coated so that the solid content is 1 g / m ² , then first dried at 70 ° C. for 30 seconds, then 14
It was dried and cured at 0 ° C. for 1 minute. After that, 20 ℃, humidity 6
After leaving for 1 day under each condition of 5% (condition 1), 60 ° C. and humidity 90% (condition 2), the coated surface was rubbed with a finger and the peeled state of the silicone was observed. ◯: Does not peel. X: Completely peeled.

[0037]

[Table 1]

Although PVA117 had a coating concentration of 7.5%, which is half of that in Example, unevenness occurred during coating. For Comparative Example 1, when a silicone resin was applied,
Due to strike-through, the adhesion test could not be performed.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location D21H 19/20 27/00 7199-3B D21H 5/00 B

Claims (4)

[Claims] 1. A radically polymerizable monofunctional vinyl monomer is emulsified in an aqueous solution containing polyvinyl alcohol using a reactive emulsifier having two or more carbon-carbon double bonds in the molecule as an emulsifier. An undercoating agent for release paper, which contains an aqueous resin obtained by polymerization as a main component. 2. A radically polymerizable monofunctional vinyl monomer and a polyfunctional monomer in an aqueous solution containing polyvinyl alcohol, wherein a reactive emulsifier having at least one carbon-carbon double bond in a molecule is used as the emulsifier. An undercoat agent for release paper, which contains an aqueous resin obtained by emulsion polymerization of a functional vinyl monomer as a main component. 3. The undercoat agent for release paper according to claim 1, wherein the monofunctional vinyl monomer is a (meth) acrylic acid alkyl ester and / or a styrene compound. 4. The undercoat agent for release paper according to claim 1, wherein the amount of polyvinyl alcohol used is 5 to 900 parts by weight based on 100 parts by weight of the total amount of vinyl monomers.