JP6835128B2 - Protective film for photoresist - Google Patents

Description

The present invention relates to a protective film for a photoresist, and provides, for example, a release film preferably used as a protective film for a photoresist used at the time of manufacturing a printed wiring board or the like.

Conventionally, polyester films typified by polyethylene terephthalate and polyethylene naphthalate have excellent mechanical strength, dimensional stability, flatness, heat resistance, chemical resistance, optical characteristics, etc., and are excellent in cost performance. , Used for various purposes.

One example of the use of a polyester film is a photoresist film used in the manufacture of printed wiring boards. The photoresist film has, for example, a three-layer structure of a carrier film / photoresist / protective film, and conventionally, a polyethylene film has been used as the protective film. The photoresist film is manufactured by drying the photoresist layer applied on the carrier film and then laminating the protective film on the photoresist layer. However, since the photoresist layer is flexible when laminating the protective film, the surface shape of the protective film. Is transferred to the photoresist layer.

In recent years, the density of printed wiring boards has been required to be increased due to the miniaturization of electronic devices, and there is an urgent need to further thin the conductor pattern formed on the surface of the insulating substrate. The polyethylene film, which is a protective film, has many irregularities due to thickness runout and fish eyes, which are transferred to the photoresist layer and the surface of the photoresist layer becomes uneven, causing poor adhesion of the photoresist layer to the insulating substrate, and the conductor pattern. It leads to defects. Therefore, the polyethylene film, which is a protective film, is one of the factors that hinder the high density of the printed wiring board.

Polyethylene film is molded by melt extrusion, but due to its high melt viscosity, it is extremely difficult to filter it with a high-performance filter during extrusion, and the problem of fish eyes and the like being present in the molded sheet is inevitable. Further, it is difficult to obtain a uniform thickness by the inflation method, which is a general film forming method for polyethylene films, and the problem of thickness runout is unavoidable. Therefore, it has become difficult to meet the demand for higher density of printed wiring boards by using a polyethylene film as a protective film.

A method of using a polyester film as a protective film as an alternative to the polyethylene film (Patent Document 1) has also been proposed. In order to ensure the releasability of the photoresist layer, the releasability is imparted by the releasable layer. However, since the releasability by the release layer is not sufficient, a copolymerization component such as a long-chain aliphatic dicarboxylic acid and / or a polyolefin is blended in the base film to impart flexibility, and the flexibility is comparable to that of a polyethylene film. Needed to be given to the polyester film. However, since a special raw material is used for the base film, there is a problem that the cost of the film is increased.

As a method of imparting releasability to a polyester film, a method of applying and laminating a silicone composition typified by polydimethylsiloxane on the surface of the polyester film has also been proposed (Patent Document 2). However, the silicone-based release film has a problem that the silicone component is transferred to the photoresist layer, and the adhesive force is lowered when the protective film is peeled off and then attached to the insulating substrate, causing defects. From these viewpoints, a polyester film having excellent mold releasability with respect to the photoresist layer is required.

Japanese Unexamined Patent Publication No. 6-297565 Japanese Unexamined Patent Publication No. 2009-143091

The present invention relates to a protective film for a photoresist, and provides, for example, a release film preferably used as a protective film for a photoresist used at the time of manufacturing a printed wiring board or the like.

As a result of diligent studies in view of the above circumstances, the present inventors have found that the above-mentioned problems can be easily solved by using a protective film having a specific configuration, and have completed the present invention.

That is, the gist of the present invention is that the polyester film contains a compound having a release layer on at least one side of the polyester film, and the release layer has a linear or branched alkyl group having 6 or more carbon atoms. It exists in a protective film for a photoresist, which is characterized in that the polyester used is formed by using a titanium compound or a germanium compound as a polymerization catalyst.

According to the protective film of the present invention, as a protective film for a photoresist, a release film having excellent releasability to a photoresist layer can be provided, and its industrial value is high.

The polyester film constituting the protective film in the present invention may have a single-layer structure or a multi-layer structure, and has four or more layers as long as the gist of the present invention is not exceeded in addition to the two-layer and three-layer structure. It may be multi-layered and is not particularly limited.

The polyester used in the present invention may be a homopolyester or a copolymerized polyester. When it is made of homopolyester, it is preferably obtained by polycondensing an aromatic dicarboxylic acid and an aliphatic glycol. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid, and examples of the aliphatic glycol include ethylene glycol, diethylene glycol and 1,4-cyclohexanedimethanol. Examples of typical polyesters include polyethylene terephthalate and the like. On the other hand, examples of the dicarboxylic acid component of the copolymerized polyester include isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, sebacic acid, and oxycarboxylic acid (for example, p-oxybenzoic acid). One or more of them may be mentioned, and examples of the glycol component include one or more of ethylene glycol, diethylene glycol, propylene glycol, butanediol, 4-cyclohexanedimethanol, neopentyl glycol and the like.

From the viewpoint of producing a film that can withstand various processing conditions, it is preferable that the film has high mechanical strength and heat resistance (dimensional stability due to heating), and for that purpose, it is preferable that the amount of the copolymerized polyester component is small. Specifically, the proportion of the monomer forming the copolymerized polyester in the polyester film is preferably in the range of 10 mol% or less, more preferably 5 mol% or less, and more preferably produced as a by-product during homopolyester polymerization. It is a degree that contains 3 mol% or less of a diether component. A more preferable form of polyester is, in consideration of mechanical strength and heat resistance, a film formed from polyethylene terephthalate or polyethylene naphthalate, which is polymerized from terephthalic acid and ethylene glycol, more preferably among the above compounds. A film formed from polyethylene terephthalate is more preferable in consideration of ease of use and handleability as a surface protective film.

The polyester polymerization catalyst is not particularly limited, and conventionally known compounds can be used. Examples thereof include antimony compounds, titanium compounds, germanium compounds, manganese compounds, aluminum compounds, magnesium compounds and calcium compounds. Among these, titanium compounds and germanium compounds have high catalytic activity, can be polymerized in a small amount, and the amount of metal remaining in the film is small, so that the brightness of the film is high and the inspection is performed through the film. It is preferable from the viewpoint of visibility. Further, since the germanium compound is expensive, it is more preferable to use a titanium compound.

It is preferable to add particles to the polyester layer of the film of the present invention mainly for the purpose of imparting slipperiness and preventing scratches in each step. When there are no particles or there are few particles, the transparency of the film is high and the film is good, but the slipperiness may be insufficient, so that the film tends to be easily scratched.

When the particles are blended, the type of the particles to be blended is not particularly limited as long as the particles can impart slipperiness, and specific examples thereof include, for example, silica, calcium carbonate, magnesium carbonate, and barium carbonate. , Calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, titanium oxide and other inorganic particles, acrylic resin, styrene resin, urea resin, phenol resin, epoxy resin, benzoguanamine resin and other organic particles. Further, during the polyester manufacturing process, precipitated particles in which a part of a metal compound such as a catalyst is precipitated and finely dispersed can also be used.

When the polyester film contains particles, it is preferable to have a three-layer structure from the viewpoint of ensuring transparency without reducing slipperiness, and further, considering the ease of production, the three-layer structure is used. Is more preferable, and the configuration in which the particles are contained in the outermost layer is optimal.

On the other hand, the shape of the particles to be used is not particularly limited, and any of spherical, lumpy, rod-shaped, flat-shaped and the like may be used. Further, the hardness, specific gravity, color and the like are not particularly limited. Two or more kinds of these series of particles may be used in combination, if necessary.

The average particle size of the particles used is preferably in the range of 5 μm or less, more preferably 0.1 to 3 μm. If the average particle size exceeds 5 μm, the surface roughness of the film may become too coarse, which may affect the surface shape of the molded surface to be transferred.

Further, the particle content in the polyester layer is preferably in the range of 5% by weight or less, more preferably 0.0003 to 3% by weight. If the particle content exceeds 5% by weight, the transparency of the film may be insufficient.

The method of adding the particles to the polyester layer is not particularly limited, and a conventionally known method can be adopted. For example, it can be added at any stage in the production of the polyester constituting each layer, but it is preferably added after the esterification or transesterification reaction is completed.

The polyester film in the present invention contains, if necessary, a conventionally known antioxidant, antistatic agent, heat stabilizer, ultraviolet absorber, lubricant, dye, pigment, etc., in addition to the above-mentioned particles. Can be done.

The thickness of the polyester film in the present invention is not particularly limited as long as it can be formed as a film, but is preferably 1 to 300 μm, more preferably 1 to 300 μm, from the viewpoints of mechanical strength, handleability, productivity and the like. Is preferably in the range of 5 to 100 μm, more preferably 8 to 50 μm.

As a film-forming method for the film of the present invention, a generally known film-forming method can be adopted, and there is no particular limitation. For example, in the case of producing a biaxially stretched polyester film, first, the polyester raw material described above is melt-extruded from a die using an extruder, and the molten sheet is cooled and solidified with a cooling roll to obtain an unstretched sheet. In this case, in order to improve the flatness of the sheet, it is preferable to improve the adhesion between the sheet and the rotary cooling drum, and the electrostatic application adhesion method and the liquid coating adhesion method are preferably adopted.

Next, the obtained unstretched sheet is stretched in one direction by a roll or tenter type stretching machine. The stretching temperature is usually 70 to 120 ° C., preferably 80 to 110 ° C., and the stretching ratio is usually 2.5 to 7 times, preferably 3.0 to 6 times. Then, in the direction orthogonal to the stretching direction of the first stage, stretching is usually performed at 70 to 170 ° C. and a stretching ratio is usually 2.5 to 7 times, preferably 3.0 to 6 times. A method of obtaining a biaxially oriented film by subsequently performing heat treatment at a temperature of 180 to 270 ° C. under tension or relaxation within 30% can be mentioned. In the above stretching, a method of stretching in one direction in two or more steps can also be adopted. In that case, it is preferable to finally set the stretching ratios in the two directions within the above ranges.

Further, in the present invention, the simultaneous biaxial stretching method can be adopted for producing the polyester film constituting the protective film. The simultaneous biaxial stretching method is a method of simultaneously stretching and orienting the unstretched sheet in the mechanical direction and the width direction while the temperature is controlled at 70 to 120 ° C., preferably 80 to 110 ° C., and the stretching ratio is Is 4 to 50 times, preferably 7 to 35 times, and more preferably 10 to 25 times in area magnification. Then, the heat treatment is subsequently performed at a temperature of 170 to 270 ° C. under tension or relaxation within 30% to obtain a stretch-oriented film. As for the simultaneous biaxial stretching apparatus that employs the above-mentioned stretching method, conventionally known stretching methods such as a screw method, a pantograph method, and a linear drive method can be adopted.

Next, the formation of the release layer constituting the protective film in the present invention will be described. Regarding the release layer, the film surface may be treated during the film forming process of the polyester film, which may be provided by in-line coating, or an offline coating which is applied outside the system on the once produced film may be adopted. More preferably, it is formed by in-line coating.

The in-line coating is a method of coating in the process of manufacturing a polyester film, and specifically, a method of coating at an arbitrary stage from melt extrusion of polyester to heat fixing and winding after stretching. Usually, it is coated on any of an unstretched sheet obtained by melting and quenching, a stretched uniaxially stretched film, a biaxially stretched film before heat fixing, and a film after heat fixing and before winding.

Although not limited to the following, for example, in sequential biaxial stretching, a method of coating a uniaxially stretched film stretched in the longitudinal direction (longitudinal direction) and then stretching in the lateral direction is particularly excellent. According to this method, since film formation and release layer formation can be performed at the same time, there is an advantage in manufacturing cost, and in order to perform stretching after coating, the thickness of the release layer is changed by the stretching ratio. Also, thin film coating can be performed more easily than offline coating. Further, by providing the release layer on the film before stretching, the release layer can be stretched together with the base film, whereby the release layer can be firmly adhered to the base film. Further, in the production of a biaxially stretched polyester film, the film can be restrained in the vertical and horizontal directions by stretching while gripping the end of the film with a clip or the like, and in the heat fixing step, a flat surface without wrinkles or the like. High temperature can be applied while maintaining the sex. Therefore, since the heat treatment applied after coating can be set to a high temperature which cannot be achieved by other methods, the film-forming property of the release layer is improved, and the release layer and the base film are more firmly adhered to each other. It is possible to prevent the release component from migrating to the photoresist layer. Further, a strong release layer can be formed, and the performance and durability of the release layer can be improved. Therefore, as a method for forming a release layer on at least one side of the polyester film, a production method in which a coating liquid containing a release component is applied to the polyester film and then stretched in at least one direction is preferable.

In the present invention, it is an essential requirement that the polyester film has a release layer on at least one side, and the release layer contains a long-chain alkyl group-containing compound.

The release layer in the present invention is provided, for example, to impart releasability that can be suitably used for peeling the protective film from the photoresist layer when used as a protective film for a photoresist.

As a result of various studies, the present inventors maintained the releasability to the photoresist layer by incorporating a long-chain alkyl group-containing compound into the release layer, and after peeling off the polyester film, the photoresist. It was found that there is no migration of silicone to the layer and it is possible to maintain the adhesion of the photoresist layer to the insulating substrate.

The long-chain alkyl group-containing compound contained in the release layer of the protective film of the present invention is used to improve the release property of the polyester film.

The long-chain alkyl compound is a compound having a linear or branched alkyl group having usually 6 or more carbon atoms, preferably 8 or more carbon atoms, and more preferably 12 or more carbon atoms. Examples of the alkyl group include a hexyl group, an octyl group, a decyl group, a lauryl group, an octadecyl group, a behenyl group and the like. Examples of the compound having an alkyl group include various long-chain alkyl group-containing polymer compounds, long-chain alkyl group-containing amine compounds, long-chain alkyl group-containing ether compounds, and long-chain alkyl group-containing quaternary ammonium salts. .. Considering heat resistance and stain resistance, a polymer compound is preferable. Further, from the viewpoint of effectively obtaining releasability, a polymer compound having a long-chain alkyl group in the side chain is more preferable.

The polymer compound having a long-chain alkyl group in the side chain can be obtained by reacting a polymer having a reactive group with a compound having an alkyl group capable of reacting with the reactive group. Examples of the reactive group include a hydroxyl group, an amino group, a carboxyl group, an acid anhydride and the like.
Examples of the compound having these reactive groups include polyvinyl alcohol, polyethyleneimine, polyethyleneamine, a reactive group-containing polyester resin, and a reactive group-containing poly (meth) acrylic resin. Among these, polyvinyl alcohol is preferable in consideration of releasability and ease of handling.

The compounds having an alkyl group capable of reacting with the above-mentioned reactive groups include, for example, long-chain alkyl group-containing isocyanates such as hexyl isocyanate, octyl isocyanate, decyl isocyanate, lauryl isocyanate, octadecyl isocyanate, and behenyl isocyanate, hexyl chloride, and octyl chloride. , Desicyl chloride, lauryl chloride, octadecyl chloride, behenyl chloride and the like, long-chain alkyl group-containing acid chlorides, long-chain alkyl group-containing amines, long-chain alkyl group-containing alcohols and the like. Among these, long-chain alkyl group-containing isocyanates are preferable, and octadecyl isocyanates are particularly preferable, in consideration of releasability and ease of handling.

Further, the polymer compound having a long-chain alkyl group in the side chain can also be obtained by copolymerizing a polymer of a long-chain alkyl (meth) acrylate or a long-chain alkyl (meth) acrylate with another vinyl group-containing monomer. .. Examples of the long-chain alkyl (meth) acrylate include hexyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, octadecyl (meth) acrylate, and behenyl (meth) acrylate. Be done.

Further, in the present invention, in order to improve the releasability of the film, it is essential to use a long-chain alkyl group-containing compound, but in addition to this, a plurality of conventionally known releasable agents may be used in combination. Examples of conventionally known release agents include waxes, fluorine compounds, silicone compounds and the like. However, it is desirable that the release layer of the present invention is formed of a non-silicone compound release agent from the viewpoint that the adhesion of the silicone component to the photoresist layer may reduce the adhesion to the insulating substrate. .. "Formed with a release agent of a non-silicone compound" means that the silicone compound content of the release layer is preferably 10% by weight or less, more preferably 5% by weight or less, still more preferably 1% by weight or less, particularly preferably. Is 0.5% by weight or less, and most preferably, it means that it is not intentionally contained. Even if the silicone compound is not actively used, there is a possibility that contamination derived from foreign substances and stains adhering to the film manufacturing process line and equipment may be mixed.

The silicone compound is a compound having a silicone structure in the molecule, and examples thereof include silicone emulsion, acrylic graft silicone, silicone graft acrylic, amino-modified silicone, perfluoroalkyl-modified silicone, and alkyl-modified silicone.

In forming the release layer of the film of the present invention, it is preferable to contain a cross-linking agent in order to improve the strength of the release layer, the adhesion to the substrate, and the heat resistance.

Examples of the cross-linking agent used in the present invention include melamine compounds, isocyanate compounds, oxazoline compounds, epoxy compounds, carbodiimide compounds and the like. Among these cross-linking agents, it is preferable to use a melamine compound or an isocyanate compound from the viewpoint of good coating film strength. Further, a melamine compound is preferable from the viewpoint of excellent releasability of the release layer. Further, an isocyanate compound is particularly preferable from the viewpoint that the release layer has excellent heat resistance and has little effect on the release property even when a heat treatment is applied during processing.
In addition, two or more of these cross-linking agents may be used in combination.

A melamine compound is a compound having a melamine skeleton in the compound, for example, an alkylolated melamine derivative, a compound obtained by reacting an alcoholylated melamine derivative with an alcohol to partially or completely etherify, and these. A mixture can be used. Examples of alkylolization include methylolation, ethylolation, isopropyrolization, n-butyrolization, and isobutyrolization. Among these, methylolation is preferable from the viewpoint of reactivity. Further, as the alcohol used for etherification, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, isobutanol and the like are preferably used. From the viewpoint of improving the strength of the coating film and improving the adhesion between the release layer and the base material, it is preferable that the alkylolated melamine derivative is partially etherified, and the alkylol is etherified with methyl alcohol. Is more preferable. Therefore, a more preferable form is partially etherified melamine having a methylol group and a methoxymethyl group. The etherified alkylol group is preferably 0.5 to 5 equivalents, more preferably 0.7 to 3 equivalents, relative to the non-etherified alkylol group. Further, the melamine compound may be either a monomer or a multimer of a dimer or more, or a mixture thereof may be used. Further, a melamine that is copolymerized with urea or the like can be used, or a catalyst can be used to increase the reactivity of the melamine compound.

The isocyanate-based compound is a compound having an isocyanate derivative structure represented by blocked isocyanate having a structure in which the isocyanate group of the isocyanate compound which is a precursor is protected by a blocking agent. Examples of the isocyanate include an aliphatic isocyanate compound, an alicyclic isocyanate compound, and an aromatic isocyanate compound. These isocyanate compounds are more preferably compounds having a plurality of isocyanate groups, that is, polyisocyanate compounds, from the viewpoint that they can react more highly and the heat resistance of the release layer can be improved. Further, when an aqueous coating liquid is used, it is more preferably blocked isocyanate.

Examples of the aliphatic polyisocyanate compound are derived from aliphatic diisocyanates such as tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethyl-1,6-diisocyanatohexane, and lysine diisocyanate. Polyisocyanate compounds, lysocyanate triisocyanates, 4-isocyanatomethyl-1,8-octamethylene diisocyanate, bis (2-isocyanatoethyl) 2-isocyanatoglutarate, compounds derived from these isocyanate compounds, etc. be able to. Among them, hexamethylene diisocyanate is preferable because of its easy industrial availability.

Examples of the alicyclic polyisocyanate compound include isophorone diisocyanate (, 1,3-bis (isocyanatomethyl) -cyclohexane, 4,4'-dicyclohexylmethanediisocyanate, norbornene diisocyanate, hydrogenated xylylene diisocyanate, or these isocyanates. Examples thereof include compounds derived from compounds. Among them, isophorone diisocyanate is preferable from the viewpoint of weather resistance and easy industrial availability.

Examples of the aromatic polyisocyanate compound are 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, or derived from these isocyanate compounds. Compounds and the like can be mentioned.

Among these polyisocyanate compounds, aliphatic polyisocyanate compounds and alicyclic polyisocyanate compounds are preferable because they have excellent weather resistance. Further, among the aliphatic polyisocyanate compounds, the aliphatic polyisocyanate compound derived from the aliphatic diisocyanate is preferable. Among them, hexamethylene diisocyanate is particularly preferable. Further, these isocyanate compounds may be used alone or in combination of two or more.

The blocked polyisocyanate compound can be synthesized by reacting the isocyanate group of the polyisocyanate compound with a blocking agent.

Examples of the blocking agent include active methylene, oxime, pyrazole, alcohol, alkylphenol, phenol, mercaptan, acid amide, acid imide, imidazole, urea, amine, imine, and heavy. Examples thereof include a sulfite blocking agent. Among these, an active methylene-based blocking agent is preferable from the viewpoint that the peeling characteristics after heating are not likely to change. In addition, two or more of these blocking agents may be used in combination.

Examples of the active methylene blocking agent include isobutanoyl acetate, n-propanoyl acetate, n-butanoyl acetate, n-pentanoyl acetate, n-hexanoyl acetate, 2-ethylheptanoyl acetate, malonic acid ester, and the like. Examples thereof include acetoacetic acid ester and acetylacetone. Among them, isobutanoyl acetate, n-propanoyl acetate, n-butanoyl acetate, n-pentanoyl acetate, n-hexanoyl acetate, 2-, in terms of excellent low-temperature curability and storage stability in the presence of water. Ethylheptanoyl acetate is preferred, more preferably isobutanoyl acetate, n-propanoyl acetate, n-pentanoyl acetate, and even more preferably isobutanoyl acetate. More specifically, examples of the isobutanoyl acetate include methyl isobutanoyl acetate, ethyl isobutanoyl acetate, n-propyl isobutanoyl acetate, isopropyl isobutanoyl acetate, n-butyl isobutanoyl acetate, isobutyl isobutanoyl acetate, t-butyl isobutanoyl acetate, and isobutanoyl acetate. Examples thereof include n-pentyl, n-hexyl isobutanoyl acetate, 2-ethylhexyl isobutanoyl acetate, phenyl isobutanoyl acetate and benzyl isobutanoyl acetate. Among them, methyl isobutanoyl acetate and ethyl isobutanoyl acetate are preferable. Examples of the n-propanoyl acetate include methyl n-propanoyl acetate, ethyl n-propanoyl acetate, isopropyl n-propanoyl acetate, n-butyl n-propanoyl acetate, t-butyl n-propanoyl acetate and the like. Among them, methyl n-propanoyl acetate and ethyl n-propanoyl acetate are preferable. Examples of the n-pentanoyl acetate include methyl n-pentanoyl acetate, ethyl n-pentanoyl acetate, isopropyl n-pentanoyl acetate, n-butyl n-pentanoyl acetate, t-butyl n-pentanoyl acetate and the like. Among them, methyl n-pentanoyl acetate and ethyl n-pentanoyl acetate are preferable.

In the active methylene block isocyanate compound used in the film of the present invention, the active methylene block agent shown above can be used alone, or two or more of them can be used in combination. As the active methylene-based blocking agent to be used in combination, dimethyl malonate and diethyl malonate are preferable because they have excellent low-temperature curability and excellent heat resistance of the formed release layer.

Examples of the oxime-based blocking agent include formaldehyde, acetaldehyde, acetone oxime, methyl ethyl keto oxime, cyclohexanone oxime and the like.

Examples of the pyrazole-based blocking agent include pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole and the like. Examples of the alcohol-based blocking agent include methanol, ethanol, 2-propanol, n-butanol, sec-butanol, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol and the like. Be done.

Examples of the alkylphenol-based blocking agent include monoalkylphenols such as n-propylphenol, isopropylphenol, n-butylphenol, sec-butylphenol, t-butylphenol, n-hexylphenol, 2-ethylhexylphenol, n-octylphenol, and n-nonylphenol. Kind, di-n-propylphenol, diisopropylphenol, isopropylcresol, di-n-butylphenol, di-t-butylphenol, di-sec-butylphenol, di-n-octylphenol, di-2-ethylhexylphenol, di-n- Examples thereof include dialkylphenols such as nonylphenol.

Examples of the phenolic blocking agent include phenol, cresol, ethylphenol, styrenated phenol, hydroxybenzoic acid ester and the like.

Examples of the mercaptan-based blocking agent include butyl mercaptan and dodecyl mercaptan.

Examples of the acid amide-based blocking agent include acetanilide, acetate amide, ε-caprolactam, δ-valerolactam, γ-butyrolactam and the like.

Examples of the acid imide-based blocking agent include succinate imide and maleate imide.

Examples of the imidazole-based blocking agent include imidazole, 2-methylimidazole and the like.

Examples of the urea-based blocking agent include urea, thiourea, ethylene urea and the like.

Examples of the amine-based blocking agent include diphenylamine, aniline, carbazole, din-propylamine, diisopropylamine, isopropylethylamine and the like. Examples of the imine-based blocking agent include ethyleneimine and polyethyleneimine.

The blocked isocyanate compound used in the film of the present invention preferably contains a hydrophilic moiety in order to enhance the compoundability in the water-based paint, and as a method for adding the hydrophilic moiety to the blocked isocyanate compound, for example, a precursor. Examples thereof include a method of reacting an isocyanate group of an isocyanate compound with a hydrophilic compound having active hydrogen.

Examples of the hydrophilic compound having active hydrogen used in the blocked isocyanate compound used in the film of the present invention include polyethylene glycol-based compounds, carboxylic acid-containing compounds, sulfonic acid-containing compounds, amine-containing compounds and the like. These hydrophilic compounds may be used alone or in combination of two or more.

Examples of polyethylene glycol-based compounds include monoalkoxypolyethylene glycol, polyethylene glycol, polyoxypropylene polyoxyethylene copolymer diol, and polyoxypropylene polyoxyethylene block polymer diol. Among them, monomethoxypolyethylene glycol and mono Monoalkoxypolyethylene glycols such as ethoxypolyethylene glycol are preferred.

Examples of the carboxylic acid group-containing compound include monohydroxycarboxylic acid, dihydroxycarboxylic acid, and derivatives thereof. Among the carboxylic acid group-containing compounds, monohydroxycarboxylic acid or dihydroxycarboxylic acid is preferable, and monohydroxycarboxylic acid is more preferable.

Specific examples of the carboxylic acid-containing compound include hydroxypivalic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, or polycaprolactone diols and polyether polyols using these as initiators. Derivatives and salts thereof.

Examples of the sulfonic acid group-containing compound include aminoethyl sulfonic acid, ethylenediamino-propyl-β-ethyl sulfonic acid, 1,3-propylene diamine-β-ethyl sulfonic acid, and N, N-bis (2-hydroxyethyl) -2. -Aminoethane sulfonic acids, and salts thereof.

Examples of the amine-containing compound include a hydroxyl group-containing amino compound. Specific examples thereof include dimethylethanolamine and diethylethanolamine.

The cross-linking agent used in the present invention is designed to react in the drying process and the film forming process to improve the performance of the release layer. It can be inferred that unreacted products of these cross-linking agents, compounds after the reaction, or mixtures thereof are present in the completed release layer.

For the formation of the release layer of the film of the present invention, various polymers can be used in combination in order to improve the coating appearance, transparency, and control the release property.

Specific examples of the polymer include polyester resin, acrylic resin, urethane resin, polyvinyl (polyvinyl alcohol, vinyl chloride vinyl acetate copolymer, etc.), polyalkylene glycol, polyalkyleneimine, methyl cellulose, hydroxycellulose, starches and the like. .. Among these, polyester resin, urethane resin, and acrylic resin are preferable, and polyester resin is more preferable, in that the releasability can be easily controlled.

Examples of the polyester resin include those composed of the following polyvalent carboxylic acids and polyvalent hydroxy compounds as main constituents. That is, as the polyvalent carboxylic acid, terephthalic acid, isophthalic acid, orthophthalic acid, phthalic acid, 4,4'-diphenyldicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid and 2,6 -Naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2-potassium sulfoterephthalic acid, 5-sodiumsulfoisophthalic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, glutal Acids, succinic acid, trimellitic acid, trimesic acid, pyromellitic acid, trimellitic anhydride, phthalic anhydride, p-hydroxybenzoic acid, monopotassium trimellitic acid and ester-forming derivatives thereof can be used. As polyvalent hydroxy compounds, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 2 -Methyl-1,5-pentanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, p-xylyleneglycol, bisphenol A-ethyleneglycol adduct, diethyleneglycol, triethyleneglycol , Polyethylene glycol, Polypropylene glycol, Polytetramethylene glycol, Polytetramethylene oxide glycol, Dimethylolpropionic acid, Glycerin, Trimethylolpropane, Sodium dimethylolethylsulfonate, Dimethylpropion Potassium acid or the like can be used. One or more of each of these compounds may be appropriately selected, and a polyester resin may be synthesized by a conventional polycondensation reaction.

The urethane resin is a polymer compound having a urethane bond in the molecule. Urethane resins are usually made by the reaction of polyol and isocyanate. Examples of the polyol include polycarbonate polyols, polyester polyols, polyether polyols, polyolefin polyols, and acrylic polyols, and these compounds may be used alone or in a plurality of types.

Polycarbonate polyols are obtained from polyhydric alcohols and carbonate compounds by a dealcohol reaction. Examples of polyhydric alcohols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentane. Diol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decane Examples thereof include diols, neopentyl glycol, 3-methyl-1,5-pentanediol, and 3,3-dimethylol heptane. Examples of the carbonate compound include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate and the like, and examples of the polycarbonate-based polyols obtained from these reactions include poly (1,6-hexylene) carbonate and poly (3-). Methyl-1,5-pentylene) carbonate and the like can be mentioned.

Polypolypolyols include polyvalent carboxylic acids (malonic acid, succinic acid, glutaric acid, adipic acid, pimeric acid, suberic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid, etc.) or their acid anhydrides. Products and polyhydric alcohols (ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 2-Methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-methyl-2,4-pentanediol , 2-Methyl-2-propyl-1,3-propanediol, 1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2 , 5-Diol-2,5-hexanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-butyl-2 -Hexyl-1,3-propanediol, cyclohexanediol, bishydroxymethylcyclohexane, dimethanolbenzene, bishydroxyethoxybenzene, alkyldialkanolamine, lactonediol, etc.) can be mentioned.

Examples of the polyether polyols include polyethylene glycol, polypropylene glycol, polyethylene propylene glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol and the like.

Examples of the polyisocyanate compound used to obtain a urethane resin include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylenedi isocyanate, naphthalene diisocyanate, and trizine diisocyanate, α, α, α', and α'. − Aromatic diisocyanates such as tetramethylxylylene diisocyanate, methylene diisocyanates, propylene diisocyanates, lysine diisocyanates, trimethylhexamethylene diisocyanates, aliphatic diisocyanates such as hexamethylene diisocyanates, cyclohexane diisocyanates, methylcyclohexane diisocyanates, isophorone diisocyanates, dicyclohexyls. Examples thereof include alicyclic diisocyanates such as methane diisocyanate and isopropyridene dicyclohexyl diisocyanate. These may be used alone or in combination of two or more.

A chain extender may be used when synthesizing the urethane resin, and the chain extender is not particularly limited as long as it has two or more active groups that react with the isocyanate group, and is generally a hydroxyl group. Alternatively, a chain extender having two amino groups can be mainly used.

Examples of the chain extender having two hydroxyl groups include aliphatic glycols such as ethylene glycol, propylene glycol and butanediol, aromatic glycols such as xylylene glycol and bishydroxyethoxybenzene, and esters such as neopentyl glycol hydroxypivalate. Examples of glycols such as glycols can be mentioned. Examples of the chain extender having two amino groups include aromatic diamines such as tolylene diamine, xylylene diamine, and diphenylmethanediamine, ethylenediamine, propylenediamine, hexanediamine, 2,2-dimethyl-1,3-. Propanediamine, 2-methyl-1,5-pentanediamine, trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10- Aliphatic diamines such as decanediamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, isopropylidenecyclohexyl-4,4'-diamine, 1,4-diaminocyclohexane, 1, Examples thereof include alicyclic diamines such as 3-bisaminomethylcyclohexane.

The urethane resin may use a solvent as a medium, but is preferably water as a medium. To disperse or dissolve the urethane resin in water, there are a forced emulsification type using an emulsifier, a self-emulsification type in which a hydrophilic group is introduced into the urethane resin, a water-soluble type, and the like. In particular, a self-emulsifying type in which an ionic group is introduced into the structure of a urethane resin to form an ionomer is preferable because it is excellent in storage stability of the liquid, water resistance of the obtained coating layer, and transparency. Examples of the ionic group to be introduced include various types such as a carboxyl group, a sulfonic acid, a phosphoric acid, a phosphonic acid, and a quaternary ammonium salt, and a carboxyl group is preferable. As a method for introducing a carboxyl group into the urethane resin, various methods can be taken in each stage of the polymerization reaction. For example, there are a method of using a resin having a carboxyl group as a copolymerization component and a method of using a component having a carboxyl group as one component of a polyol, a polyisocyanate, a chain extender, etc. at the time of prepolymer synthesis. In particular, a method of using a carboxyl group-containing diol and introducing a desired amount of carboxyl groups according to the amount of this component charged is preferable. For example, copolymerizing dimethylolpropionic acid, dimethylolbutanoic acid, bis- (2-hydroxyethyl) propionic acid, bis- (2-hydroxyethyl) butanoic acid, etc. with the diol used for polymerizing the urethane resin. Can be done. Further, this carboxyl group is preferably in the form of a salt neutralized with ammonia, amines, alkali metals, inorganic alkalis and the like. Particularly preferred are ammonia, trimethylamine and triethylamine. In such a polyurethane resin, the carboxyl group from which the neutralizing agent has been removed in the drying step after coating can be used as a cross-linking reaction point by another cross-linking agent. As a result, the stability of the liquid before coating is excellent, and the durability, solvent resistance, water resistance, blocking resistance, etc. of the obtained release layer can be further improved.

The acrylic resin is a polymer composed of a polymerizable monomer containing an acrylic-based or methacrylic-based monomer. These may be homopolymers or copolymers, and may be copolymers with polymerizable monomers other than acrylic and methacrylic monomers. Also included are copolymers of these polymers with other polymers (eg polyester, polyurethane, etc.). For example, block copolymers and graft copolymers. Alternatively, a polymer (possibly a mixture of polymers) obtained by polymerizing a polymerizable monomer in a polyester solution or a polyester dispersion is also included. Similarly, a polymer (in some cases, a mixture of polymers) obtained by polymerizing a polymerizable monomer in a polyurethane solution or a polyurethane dispersion is also included. Similarly, a polymer (in some cases, a polymer mixture) obtained by polymerizing a polymerizable monomer in another polymer solution or dispersion is also included. Further, it is also possible to contain a hydroxyl group and an amino group in order to further improve the adhesion to the base material.

The polymerizable monomer is not particularly limited, but typical compounds include various carboxyl groups such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, and citraconic acid. Monomers and salts thereof; such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, monobutylhydroquilfumarate, monobutylhydroxyitaconate. Various hydroxyl group-containing monomers; Various (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and lauryl (meth) acrylate; Various nitrogen-containing compounds such as meta) acrylamide, diacetone acrylamide, N-methylol acrylamide or (meth) acrylonitrile; various styrene derivatives such as styrene, α-methylstyrene, divinylbenzene, vinyltoluene, vinyl propionate. Various vinyl esters such as; various silicon-containing polymerizable monomers such as γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, etc .; phosphorus-containing vinyl-based monomers; various types such as vinyl chloride, billidene chloride. Vinyl halides; various conjugated dienes such as butadiene can be mentioned.

As a ratio of the release layer constituting the protective film in the present invention to all non-volatile components, the long-chain alkyl group-containing compound is usually in the range of 3% by weight or more, preferably in the range of 5 to 95% by weight, more preferably 10 to 10% by weight. It is in the range of 90% by weight. If it is less than 3% by weight, sufficient mold release performance may not be obtained.

When a cross-linking agent is used in combination with the release layer, and when a melamine compound is used as the cross-linking agent, the ratio of the long-chain alkyl group-containing compound to the total non-volatile components of the release layer is preferably in the range of 10 to 95% by weight. The range of 20 to 90% by weight is more preferable, and the range of 30 to 85% by weight is particularly preferable.

When an isocyanate compound is used as the cross-linking agent, the ratio of the long-chain alkyl group-containing compound to the total non-volatile components of the release layer is preferably in the range of 5 to 95% by weight, more preferably in the range of 15 to 93% by weight. The range of 25 to 90% by weight is particularly preferable.

When a cross-linking agent is used in combination with the release layer constituting the protective film in the present invention, the ratio of the cross-linking agent to the total non-volatile components of the release layer is preferably in the range of 97% by weight or less, more preferably 5 to 95% by weight. %, More preferably 10 to 90% by weight. By using it in the above range, it is possible to improve the heat resistance of the release layer, and it is possible to maintain sufficient releasability even after the heat treatment.

When a melamine compound is used as the cross-linking agent, the ratio of the melamine compound to the total non-volatile components of the release layer is preferably in the range of 5 to 90% by weight, more preferably in the range of 10 to 80% by weight, and 15 to 70% by weight. The% range is particularly preferred.

When an isocyanate compound is used as the cross-linking agent, the ratio of the isocyanate compound to the total non-volatile components of the release layer is preferably in the range of 5 to 95% by weight, more preferably in the range of 7 to 85% by weight, and 10 to 10% by weight. The range of 75% by weight is particularly preferable.

The releasability of the releasable layer of the present invention depends on the type of material of the photoresist layer, but when expressed as a peeling force against an acrylic adhesive tape, for example, it is preferably 1000 mN / cm or less, more preferably 500 mN / cm or less. More preferably, it is 200 mN / cm or less, and particularly preferably 170 mN / cm or less. The lower limit of the peeling force is preferably 10 mN / cm.

The peeling force of the release layer of the present invention after heat treatment on the acrylic adhesive tape depends on the value of the peeling force before heating, but the peeling force after heating at 100 ° C. for 1 hour is preferably 1700 mN /. It is cm or less, more preferably 1100 mN / cm or less, still more preferably 850 mN / cm or less, and particularly preferably 750 mN / cm or less. Within the above range, the adhesive layer can be successfully peeled off even if heat treatment is applied. The lower limit of the peeling force after the heat treatment is preferably 10 mN / cm.

The release layer in the present invention is characterized in that it is laminated on at least one side of the polyester film, but a functional layer different from the release layer may be provided on the other side of the polyester film. The functional layer is not particularly limited, and examples thereof include an antistatic layer, an antifouling layer, and an antiblocking layer. Among these, when a polyester film is used as a protective film, it is preferably a layer containing an antistatic agent for the purpose of suppressing static electricity generated when the film is peeled off.

Regarding the protective film in the present invention, the film thickness of the release layer provided on the polyester film is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm, and further preferably 0.01 to 0.2 μm. Is the range of. If the film thickness exceeds 1 μm, the appearance of the coating film may deteriorate or the coating film may not be sufficiently cured. If the film thickness is less than 0.001 μm, sufficient releasability may not be obtained. ..

Particles can also be used in combination with the formation of the release layer of the film of the present invention for the purpose of improving blocking property and slipperiness, as long as the gist of the present invention is not impaired.

Further, as long as the gist of the present invention is not impaired, a defoaming agent, a coatability improver, a thickener, an organic lubricant, an antistatic agent, an ultraviolet absorber, and an antioxidant are required for forming the release layer. It is also possible to use agents, foaming agents, dyes, pigments and the like in combination.

The analysis of the components of the release layer can be performed by, for example, analysis of TOF-SIMS, ESCA, fluorescent X-rays and the like.

When a release layer is provided by in-line coating, a coating liquid having a solid content concentration of about 0.1 to 50% by weight is applied onto a polyester film using the above series of compounds as an aqueous solution or an aqueous dispersion. It is preferable to manufacture the protective film in the same manner. Further, a small amount of an organic solvent may be contained in the coating liquid for the purpose of improving dispersibility in water, improving film-forming property, etc., as long as the gist of the present invention is not impaired. Only one kind of organic solvent may be used, and two or more kinds may be used as appropriate.

Examples of the method for forming the release layer of the present invention include a gravure coat, a reverse roll coat, a die coat, an air doctor coat, a blade coat, a rod coat, a bar coat, a curtain coat, a knife coat, a transfer roll coat, and a squeeze coat. Conventionally known coating methods such as impregnation coating, kiss coating, spray coating, calendar coating, and extrusion coating can be used.

In the present invention, regarding the drying and curing conditions when forming the release layer on the polyester film, for example, when the release layer is provided by offline coating, it is usually at 80 to 200 ° C. for 3 to 40 seconds, preferably 100. It is preferable to perform heat treatment at ~ 180 ° C. for 3 to 40 seconds as a guide.

On the other hand, when the release layer is provided by in-line coating, it is usually preferable to perform heat treatment at 70 to 270 ° C. for 3 to 200 seconds as a guide.

Further, regardless of the offline coating or the in-line coating, heat treatment and active energy ray irradiation such as ultraviolet irradiation may be used in combination as needed. The polyester film constituting the protective film in the present invention may be subjected to surface treatment such as corona treatment and plasma treatment in advance.

The protective film of the present invention can be attached to the photoresist surface of a photoresist film and used as a protective film for a photoresist layer. The photoresist film has a structure in which a photoresist layer containing a photosensitive resin composition is formed on a carrier film. The protective film is used by pressurizing and laminating on the photoresist layer.

Examples of the carrier film include a polyester film and a polypropylene film, and among them, a polyester film is particularly preferable. Examples of the polyester film include the same contents as described in the polyester film of the protective film of the present invention.

The photoresist layer is a layer containing a photosensitive resin composition. The photosensitive resin composition is a composition containing a monomer having a polymerizable unsaturated group, a polymer, a photopolymerization initiator and the like. The monomer having a polymerizable unsaturated group is not particularly limited, but a monomer having one polymerizable unsaturated group, a monomer having two polymerizable unsaturated groups, and a polymerizable unsaturated group may be used. Examples thereof include monomers having three or more, and these are used alone or in combination as appropriate.

Examples of the monomer having one polymerizable unsaturated group include methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, propyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate. ) Acrylate, butyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropylphthalate, 3-chloro-2 Examples thereof include -hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl acid phosphate, half (meth) acrylate of a phthalic acid derivative, and N-methylol (meth) acrylamide.

Examples of the monomer having two polymerizable unsaturated groups include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and propylene. Glycoldi (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide-modified bisphenol A type di (meth) acrylate, propylene oxide-modified bisphenol A type Di (meth) acrylate, ethylene oxide / propylene oxide modified bisphenol A type di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol Diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, propylene glycol diglycidyl di (meth) acrylate, diglycidyl phthalate di (meth) acrylate, hydroxypivalic acid-modified neopentyl glycol di (meth) ) Acrylate and the like can be mentioned. Of these, ethylene oxide-modified bisphenol A-type di (meth) acrylate and ethylene oxide / propylene oxide-modified bisphenol A-type di (meth) acrylate are particularly preferably used.

Examples of the monomer having three or more polymerizable unsaturated groups include trimethylolpropane tri (meth) acrylate, trimethylolpropane tripropoxy (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (dipentaerythritol penta). Examples thereof include meth) acrylate, tri (meth) acryloyloxyethoxytrimethylolpropane, and glycerin polyglycidyl ether poly (meth) acrylate.

In addition to the above, an epoxy (meth) acrylate compound, a urethane (meth) acrylate compound, a phosphorus element-containing polymerizable compound, or the like may be included.

As the monomer having a polymerizable unsaturated group, a monomer having two polymerizable unsaturated groups and having a weight average molecular weight of 1500 or less, preferably 300 to 1200 is preferable, and among them, ethylene oxide-modified bisphenol A is particularly preferable. Type di (meth) acrylate and ethylene oxide / propylene oxide modified bisphenol A type di (meth) acrylate are preferably used. If the weight average molecular weight exceeds 1,500, the distance between crosslinks becomes long and sufficient curing cannot be obtained, which is not preferable because it causes a decrease in resolution and a decrease in fine line adhesion.

The polymer contained in the photosensitive resin composition is not particularly limited, and examples thereof include a polymer composed of an acrylic-based or methacrylic-based polymerizable monomer. Either a homopolymer or a copolymer, or a copolymer with a polymerizable monomer other than an acrylic or methacrylic monomer may be used. As the polymerizable monomer, carboxyl group-containing monomers such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid, or their anhydrides, half esters, methyl (meth) acrylates, and ethyl (meth) acrylates. , Propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, hydroxyethyl ( Examples thereof include (meth) acrylates such as meta) acrylates, hydroxypropyl (meth) acrylates and glycidyl (meth) acrylates, acrylamides, methacrylicamides, acrylonitriles, methacrylonitriles, styrenes, α-methylstyrenes, vinyl acetates and alkylvinyl ethers. ..

The weight average molecular weight of the above polymer is preferably in the range of 5,000 to 250,000, more preferably 10,000 to 200,000. If the weight average molecular weight is less than 5,000, the resin may become too soft and the resin may seep out when processed into a roll form as a photoresist film, and if it exceeds 250,000, the resolution may decrease.

The glass transition temperature (Tg) of the polymer is preferably in the range of 30 to 150 ° C. If the glass transition temperature is less than 30 ° C., the resin may become too soft and the resin may seep out when processed into a roll form as a photoresist film. If the temperature exceeds 150 ° C., the resin is used as a photoresist film. There is a possibility that the ability to follow the unevenness of the substrate surface will decrease.

Conventionally known photopolymerization initiators are used as the photopolymerization initiator contained in the photosensitive resin composition. For example, benzophenone, P, P'-bis (dimethylamino) benzophenone, P, P'-bis (diethylamino) benzophenone, P, P'-bis (dibutylamino) benzophenone, 3,3'-dimethyl-4-methoxybenzophenone. Etc., benzoin derivatives such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzoin isobutyl ether and the like, quinone derivatives such as anthraquinone and naphthoquinone, 2-chlorothioxanthone, 2 -Thioxanthone derivatives such as methylthioxanthone and 2,4-diethylthioxanthone, acetophenone derivatives such as dichloroacetophenone, 2,2-diethoxyacetophenone, 2,2-dichloro-4-phenoxyacetophenone, phenylglycilate, α-hydroxyisobutyl Propanone derivatives such as phenone, dibenzosparone, 1- (4-isopropylphenyl) -2-hydroxy-2-methyl-1-propanol, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone. , Tribromophenylsulfone, sulfone derivatives such as tribromomethylphenylsulfone, 2,4,6- [tris (trichloromethyl)]-1,3,5-triazine, 2,4- [bis (trichloromethyl)]- 6- (4'-methoxyphenyl) -1,3,5-triazine, 2,4- [bis (trichloromethyl)]-6- (4'-methoxynaphthyl) -1,3,5-triazine, 2, 4- [bis (trichloromethyl)]-6- (piperonyl) -1,3,5-triazine, 2,4- [bis (trichloromethyl)]-6- (4'-methoxystyryl) -1,3, Triazine derivatives such as 5-triazine, aclysine and aclysine derivatives such as 9-phenylaclydin, 2,2'-bis (o-chlorophenyl) -4,5,4', 5'-tetraphenyl-1,2'-bi Imidazole, 2,2'-bis (o-chlorophenyl) -4,5,4', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-fluorophenyl) -4, 5,4', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-methoxyphenyl) -4,5,4', 5'-tetraphenyl-1,1'- Biimidazole, 2,2'-bis (p-meth) Xiphenyl) -4,5,4', 5'-tetraphenyl-1,1'-biimidazole, 2,4,2', 4'-bis [bi (p-methoxyphenyl)]-5,5'- Diphenyl-1,1'-biimidazole, 2,2'-bis (2,4-dimethoxyphenyl) -4,5,4', 5'-diphenyl-1,1'-biimidazole, 2,2'- Bis (p-methylthiophenyl) -4,5,4', 5'-diphenyl-1,1'-biimidazole, bis (2,4,5-triphenyl) -1,1'-biimidazole, etc. Hexaaryl biimidazole derivatives such as homomorphs co-linked with 1,2'-, 1,4'-, and 2,4'-disclosed in Japanese Patent Publication No. 45-373777, and others. , Benzoyl benzoic acid, Methyl benzoyl benzoate, benzyl diphenyl disulfide, benzyl dimethyl ketal, 2-methyl-1- [4- (methylthio) phenyl] -2-molyfornopropan-1-one, 2,2-dimethoxy-1 , 2-Diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy)- Phenyl] -2-Hydroxy-2-methyl-1-propane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, bis (2,4,6- Trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis (η5) Examples thereof include -2,4-cyclopentadiene-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) -phenyl) titanium. These may be used alone or in combination of two or more. Among these, 2,2-dimethoxy-1,2-diphenylethane-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 are preferable.

In addition, the photosensitive resin composition includes amino resins such as melamine, thermal cross-linking agents such as isocyanate compounds, crystal violet, malachite green, malachite green lake, brilliant green, patent blue, methyl violet, Victoria blue, and rose aniline. , Coloring dyes such as parafuxin and ethylene violet, adhesion imparting agents, plasticizers, antioxidants, thermal polymerization inhibitors, solvents, surface tension modifiers, stabilizers, chain transfer agents, defoaming agents, flame retardants, etc. Additives can be added.

When a photosensitive resin composition is provided on the carrier film to prepare a photoresist film, a method of mixing the photosensitive resin composition with an organic solvent so as to have a predetermined concentration can be mentioned. Examples of the organic solvent include acetone, methyl ethyl ketone, methanol, ethanol, isopropyl alcohol, toluene, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, ethyl acetate, butyl acetate and the like. These may be used alone or in combination of two or more. A coating solution containing a mixture of photosensitive resin compositions is uniformly applied to one side of the carrier film by a method such as a roll coater method or a bar coater method, and usually in an oven at 50 to 130 ° C. or gradually increasing in temperature. A photoresist film is produced by drying to form a photoresist layer and coating with a protective film.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded. The measurement method and evaluation method used in the present invention are as follows.

(1) Method for measuring the ultimate viscosity of polyester 1 g of polyester from which other polymer components and pigments incompatible with polyester have been removed is precisely weighed, and 100 ml of a mixed solvent of phenol / tetrachloroethane = 50/50 (weight ratio) is added. Was dissolved and measured at 30 ° C.

(2) Measurement of average particle size (d50) The average particle size d50 is the particle size with an integrated volume fraction of 50% in the equivalent spherical distribution measured using a centrifugal sedimentation type particle size distribution measuring device (SA-CP3 type) manufactured by Shimadzu Corporation. And said.

(3) Method for measuring the film thickness of the release layer The surface of the release layer _{was dyed with RuO 4} and embedded in an epoxy resin. Thereafter, the section prepared by ultramicrotomy stained with RuO _4, the cross section of the release layer TEM (Hitachi High Technologies Corporation H-7650, accelerating voltage 100 kV) was used for the measurement.

(4) Evaluation of release force of release layer Adhesive tape (Nitto Denko Corporation "No. 31B" base material thickness 25 μm) is applied to the surface of the release layer of the polyester film provided with the release layer with a 2 kg rubber roller. The peeling force was measured after reciprocating crimping and leaving at room temperature for 1 hour. As the peeling force, "Ezgraph" manufactured by Shimadzu Corporation was used, and 180 ° peeling was performed under the condition of a tensile speed of 300 mm / min.

(5) Evaluation of release force after heating of release film Adhesive tape (Nitto Denko Corporation "No. 31B" base material thickness 25 μm) is applied to a 2 kg rubber roller on the surface of the release layer of a polyester film provided with a release layer. After one round trip crimping, it was heated for 1 hr in an oven at 100 ° C. Then, the peeling force after being left at room temperature for 1 hour was measured. As the peeling force, "Ezgraph" manufactured by Shimadzu Corporation was used, and 180 ° peeling was performed under the condition of a tensile speed of 300 mm / min.

(6) Peelability from the photoresist layer Using the polyester film according to Comparative Example 1 having a thickness of 16 μm as a carrier film, a photosensitive resin composition having the following composition was applied to one side thereof, and the temperature was 110 ° C. for 3 minutes. , Dry to form a photoresist layer of 40 μm, put the protective film of the present invention on it so that the release layer and the photoresist layer face each other, and then pressurize and cover the photoresist film with the protective film. Created. Then, the protective film was peeled off and its peelability was evaluated.
If the peeling is smooth and the resist is not transferred to the protective film and the resist surface is not scratched, the peeling is not smooth, the resist cannot be peeled off, or the resist surface is scratched. What was done was marked as x.

(Composition of photosensitive resin composition)
As a monomer having a polymerizable unsaturated group, 30 parts of ethylene oxide-modified bisphenol A dimethacrylate and 10 parts of propylene glycol diglycidyl ether diacrylate, which have 17 repetitions of ethylene oxide (total number of repetition units). , Trimethylol Propane triacrylate, polymerized at a ratio of methyl methacrylate / n-butyl methacrylate / styrene / methacrylic acid = 45/15/15/25 (weight ratio) as a polymer, polymer with a weight average molecular weight of 170,000 25 parts, 25 parts of a polymer having a weight average molecular weight of 20,000 polymerized at a ratio of styrene / acrylic acid = 75/25 (weight ratio), as a photopolymerization initiator, 2,2-dimethoxy-1,2- 2 parts of diphenylethane-1-one, 0.4 parts of (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1), 75 parts of methyl ethyl ketone as a solvent, and isopropyl alcohol. A mixture of 25 parts.

The polyester used in Examples and Comparative Examples was prepared as follows.
<Manufacturing method of polyester (A)>
Ester 100 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol, 30 ppm of ethyl acid phosphate for the produced polyester, and 100 ppm of magnesium acetate / tetrahydrate as a catalyst for the produced polyester in a nitrogen atmosphere at 260 ° C. A chemical reaction was allowed. Subsequently, 50 ppm of tetrabutyl titanate was added to the produced polyester, the temperature was raised to 280 ° C. over 2 hours and 30 minutes, the pressure was reduced to an absolute pressure of 0.3 kPa, and the mixture was further polycondensed for 80 minutes to achieve the ultimate viscosity. A polyester (A) having 0.63 and a diethylene glycol content of 2 mol% was obtained.

<Manufacturing method of polyester (B)>
100 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol, and magnesium acetate tetrahydrate as a catalyst were subjected to an esterification reaction at 225 ° C. with 900 ppm in a nitrogen atmosphere. Subsequently, 3500 ppm of positive phosphoric acid was added to the produced polyester, and 70 ppm of germanium dioxide was added to the produced polyester, the temperature was raised to 280 ° C. over 2 hours and 30 minutes, and the pressure was reduced to an absolute pressure of 0.4 kPa. Polyester (B) having an ultimate viscosity of 0.64 and a diethylene glycol content of 2 mol% was obtained by melt polycondensation for 85 minutes.

<Manufacturing method of polyester (C)>
In the method for producing polyester (A), polyester (C) is obtained by using the same method as the method for producing polyester (A) except that 0.3 parts by weight of silica particles having an average particle size of 2 μm are added before melt polymerization. It was.

Examples of compounds constituting the release layer and the functional layer are as follows.
-Long chain alkyl group-containing compound: (I)
200 parts of xylene and 600 parts of octadecyl isocyanate were added to a four-necked flask and heated under stirring. From the time when xylene began to reflux, 100 parts of polyvinyl alcohol having an average degree of polymerization of 500 and a saponification degree of 88 mol% was added little by little at 10-minute intervals for about 2 hours. After the addition of polyvinyl alcohol was completed, reflux was carried out for another 2 hours to complete the reaction. When the reaction mixture was cooled to about 80 ° C. and then added to methanol, the reaction product precipitated as a white precipitate. This precipitate was filtered off, 140 parts of xylene was added, and the mixture was heated to completely dissolve it. After that, the operation of adding methanol again to precipitate was repeated several times, and then the precipitate was washed with methanol and dried and pulverized to obtain the precipitate.

・ Melamine compound: (IIA)
Partially etherified melamine with a ratio of methylol group to methoxy group of 1: 2.2
-Active methylene block polyisocyanate: (IIB)
1000 parts of blocked polyisocyanate hexamethylene diisocyanate synthesized by the following method was stirred at 60 ° C., and 0.1 part of tetramethylammonium caprilate was added as a catalyst. After 4 hours, 0.2 part of phosphoric acid was added to stop the reaction to obtain an isocyanurate-type polyisocyanate composition. 100 parts of the obtained isocyanurate-type polyisocyanate composition, 42.3 parts of methoxypolyethylene glycol having a number average molecular weight of 400, and 29.5 parts of propylene glycol monomethyl ether acetate were charged and held at 80 ° C. for 7 hours. Then, the temperature of the reaction solution was maintained at 60 ° C., 35.8 parts of methyl isobutanoyl acetate, 32.2 parts of diethyl malonate, and 0.88 parts of a 28% methanol solution of sodium methoxide were added and kept for 4 hours. Block polyisocyanate obtained by adding 58.9 parts of n-butanol, holding at a reaction solution temperature of 80 ° C. for 2 hours, and then adding 0.86 parts of 2-ethylhexyl acid phosphate.

-Polyester resin: (IIIA)
Aqueous dispersion of polyester resin copolymerized with the following composition Monomer composition: (acid component) terephthalic acid / isophthalic acid / 5-sodium sulfoisophthalic acid // (diol component) ethylene glycol / 1,4-butanediol / diethylene glycol = 56/40/4 // 70/20/10 (mol%)
-Acrylic resin: (IIIB) Acrylic resin polymerized with the following composition Ethyl acrylate / n-butyl acrylate / methyl methacrylate / N-methylol acrylamide / acrylic acid = 65/21/10/2/2 (% by weight) Emulsified polymer (emulsifier: anionic surfactant)
・ Urethane resin (IIIC)
An aqueous dispersion of a polyester urethane resin formed from isophorone diisocyanate / terephthalic acid / isophthalic acid / ethylene glycol / diethylene glycol / dimethylolpropane acid = 12/19/18/21/25/5 (mol%).

Example 1:
A mixed raw material in which polyesters (A), (B) and (C) are mixed at a ratio of 77%, 3% and 20%, respectively, is used as a raw material for the outermost layer (surface layer), and polyesters (A) and (B) are 97, respectively. Using the mixed raw material mixed at a ratio of% and 3% as the raw material for the intermediate layer, each of them was supplied to two extruders, melted at 285 ° C., and then placed on a cooling roll set at 40 ° C. An unstretched sheet was obtained by coextrusion, cooling and solidifying with a layer structure of layers (surface layer / intermediate layer / surface layer = 1: 6: 1 discharge amount).
Next, after stretching 3.4 times in the longitudinal direction at a film temperature of 85 ° C. using the difference in roll peripheral speed, the coating liquid 1 shown in Table 1 below was applied to one side of the vertically stretched film and guided to a tenter. After stretching 4.0 times at 100 ° C in the lateral direction and heat-treating at 230 ° C, it relaxes by 2% in the lateral direction, and a release layer having a coating layer thickness (after drying) of 0.03 μm is formed on one side. A protective film having a thickness of 16 μm was obtained. When the obtained protective film was evaluated, it was found that the initial releasability and the releasability after heating were good, and the releasability to the photoresist layer was also good. The characteristics of this film are shown in Table 2 below.

Examples 2-23:
In Example 1, a protective film was obtained in the same manner as in Example 1 except that the composition of the release layer was changed to the coating agent composition shown in Table 1. As shown in Table 2, the completed protective film had good initial releasability and releasability after heating, and also had good releasability to the photoresist layer.

Comparative Example 1:
In Example 1, a protective film was obtained by manufacturing in the same manner as in Example 1 except that the release layer was not provided. When the finished protective film was evaluated, it was as shown in Table 2, and it was a film in which the release property of the release layer was inferior and the release property to the photoresist layer was also inferior.

Comparative Examples 2-4:
In Example 1, a protective film was obtained in the same manner as in Example 1 except that the coating agent composition of the release layer was changed to the coating agent composition shown in Table 1. When the finished protective film was evaluated, it was as shown in Table 2, and it was a film in which the release property of the release layer was inferior and the release property to the photoresist layer was also inferior.

The photoresist protective film of the present invention can be suitably used as a photoresist protective film used, for example, when manufacturing a printed wiring board.

Claims (8)

At least one surface having a release layer without passing through the coating layer containing a non-heat-resistant particles, the releasing layer, containing a compound having a C 6 or more linear or branched alkyl groups of the polyester film The polyester used for the polyester film is formed by using a titanium compound or a germanium compound as a polymerization catalyst , and is used by adhering to a photoresist surface to protect the photoresist. photoresist protective film for. The polyester film has a release layer on at least one side, and the release layer contains a compound having a linear or branched alkyl group having 6 or more carbon atoms, and the polyester used in the polyester film is a polymerization catalyst. It is formed by using a titanium compound or a germanium compound, and has a peeling force of 1100 mN / cm or less after heating the acrylic adhesive tape of the release layer at 100 ° C. for 1 hour. A protective film for a photoresist that is used by adhering it to a photoresist surface to protect the photoresist. The protective film for a photoresist according to claim 1 or 2 , wherein the release layer is a layer formed by using a melamine compound. The protective film for a photoresist according to claim 1 or 2 , wherein the release layer is a layer formed by using a blocked isocyanate having a structure in which an isocyanate group is protected with an active methylene-based blocking agent. The active methylene blocking agent is at least one selected from isobutanoyl acetate, n-propanoyl acetate, n-butanoyl acetate, n-pentanoyl acetate, n-hexanoyl acetate and 2-ethylheptanoyl acetate. The protective film for a photoresist according to claim 4. The protective film for a photoresist according to claim 4 , wherein the active methylene-based blocking agent is two or more kinds. The protective film for a photoresist according to claim 6 , wherein at least one of the active methylene-based blocking agents is dimethyl malonate or diethyl malonate. A laminate obtained by laminating the photoresist protective film according to any one of claims 1 to 7 to the photoresist surface of the photoresist film.