JP2017181609A - Photoresist protection film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a release polyester film that can be suitably used as a photoresist protection film; particularly, causes no trouble and is very suitable when employed as a photoresist protection film widely used in producing printed wiring boards and others.SOLUTION: A photoresist protection film has a release layer on at least one side of a polyester film, the release layer containing a long-chain alkyl group-containing compound.SELECTED DRAWING: None

Description

  The present invention relates to a protective film for a photoresist, and provides a release film that is suitably used as a protective film for a photoresist that is used, for example, when a printed wiring board is manufactured.

  Conventionally, polyester films represented by polyethylene terephthalate and polyethylene naphthalate have excellent mechanical properties, dimensional stability, flatness, heat resistance, chemical resistance, optical properties, etc., and cost performance. It is used for various purposes.

One example of an application using a polyester film is a film for a photoresist used in the production of a printed wiring board. The photoresist film has, for example, a three-layer structure of carrier film / photoresist / protective film, and a polyethylene film has been conventionally used as the protective film. Photoresist film is manufactured by drying the photoresist layer coated on the carrier film and then laminating the protective film on the photoresist layer, but since the photoresist layer is flexible when the protective film is laminated, the surface shape of the protective film Is transferred to the photoresist layer.

  In recent years, the density of printed wiring boards has been demanded due to the miniaturization of electronic devices, and there is an urgent need for further thinning of the conductor pattern formed on the surface of the insulating substrate. Polyethylene film, which is a protective film, has many irregularities due to thickness fluctuations and fish eyes, which are transferred to the photoresist layer, resulting in irregularities on the surface of the photoresist layer, causing poor adhesion of the photoresist layer to the insulating substrate, and Leads to defects. Therefore, the polyethylene film which is a protective film contributes to the hindrance to increasing the density of the printed wiring board.

  A polyethylene film is formed by melt extrusion. However, since the melt viscosity is high, it is extremely difficult to filter with a high-performance filter during extrusion, and the problem that fish eyes and the like are present in the formed sheet is unavoidable. Furthermore, it is difficult to obtain a uniform thickness by the inflation method, which is a general method for forming a polyethylene film, and the problem of thickness fluctuation is unavoidable. Therefore, it has become difficult to meet the demand for higher density printed wiring boards using a polyethylene film as a protective film.

  A method of using a polyester film as a protective film as an alternative to a polyethylene film (Patent Document 1) has also been proposed. In order to secure the releasability with respect to the photoresist layer, the releasability is imparted by the release layer. However, since the release property of the release layer is not sufficient, the base film is blended with a copolymer component such as a long-chain aliphatic dicarboxylic acid and / or polyolefin to give flexibility, and is as flexible as a polyethylene film. 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 for 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 (Patent Document 2) has also been proposed. However, the silicone-based release film has a problem in that when the silicone component is transferred to the photoresist layer and the protective film is peeled off and then bonded to the insulating substrate, the adhesive force is reduced and a defect is caused. From these viewpoints, a polyester film having excellent releasability with respect to a photoresist layer is required.

JP-A-6-297565 JP 2009-143091 A

  The present invention relates to a protective film for a photoresist, and provides a release film that is suitably used as a protective film for a photoresist that is used, for example, when a printed wiring board is manufactured.

  As a result of intensive studies in view of the above circumstances, the present inventors have found that the above-described 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 resides in a protective film for a photoresist having a release layer on at least one surface of a polyester film, and the release layer contains a long-chain alkyl group-containing compound.

  According to the protective film of the present invention, as a protective film for a photoresist, a release film having excellent release properties with respect 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 multilayer structure, and may have four or more layers as long as the gist of the present invention is not exceeded other than the two-layer or three-layer structure. It may be a multilayer and is not particularly limited.

  The polyester used in the present invention may be a homopolyester or a copolyester. In the case of a homopolyester, those obtained by polycondensation of an aromatic dicarboxylic acid and an aliphatic glycol are preferred. 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. Typical polyester includes polyethylene terephthalate and the like. On the other hand, the dicarboxylic acid component of the copolyester includes isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, sebacic acid, oxycarboxylic acid (for example, p-oxybenzoic acid, etc.), etc. 1 type or 2 types or more are mentioned, As a glycol component, 1 type or 2 types or more, such as ethylene glycol, diethylene glycol, propylene glycol, butanediol, 4-cyclohexane dimethanol, neopentyl glycol, is mentioned.

  From the viewpoint of forming a film that can withstand various processing conditions, it is preferable that the mechanical strength and heat resistance (dimensional stability by heating) are high, and for that purpose, it is preferable that the copolymer polyester component is small. Specifically, the proportion of the monomer forming the copolyester 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 grade which contains the diether component of 3 mol% or less which is a grade which will carry out. In view of mechanical strength and heat resistance, a more preferable form of polyester is more preferably a film formed from polyethylene terephthalate or polyethylene naphthalate, which is polymerized from terephthalic acid and ethylene glycol, among the above compounds. In consideration of ease of handling and handling properties as a surface protective film, a film formed from polyethylene terephthalate is more preferable.

  There is no restriction | limiting in particular as a polymerization catalyst of polyester, A conventionally well-known compound can be used, For example, an antimony compound, a titanium compound, a germanium compound, a manganese compound, an aluminum compound, a magnesium compound, a calcium compound etc. are mentioned. Among these, titanium compounds and germanium compounds have high catalytic activity and can be polymerized in a small amount, and since the amount of metal remaining in the film is small, the brightness of the film is high and inspection is performed through the film. It is preferable from the viewpoint of visibility. Furthermore, since a germanium compound is expensive, it is more preferable to use a titanium compound.

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

  When blending the particles, the kind of the particles to be blended is not particularly limited as long as it is a particle capable of imparting slipperiness, and specific examples include, for example, silica, calcium carbonate, magnesium carbonate, barium carbonate. Inorganic particles such as calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, and titanium oxide, and organic particles such as acrylic resin, styrene resin, urea resin, phenol resin, epoxy resin, and benzoguanamine resin. In addition, it is also possible to use precipitated particles in which a part of a metal compound such as a catalyst is precipitated and finely dispersed during the polyester production process.

  In the case where particles are contained in the polyester film, the structure is preferably three or more layers from the viewpoint of ensuring transparency without deteriorating the slipperiness, and further considering the ease of production, it is a three-layer structure. Is more preferable, and the structure containing the particles 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 a spherical shape, a block shape, a rod shape, a flat shape, and the like may be used. Moreover, there is no restriction | limiting in particular also about the hardness, specific gravity, a color, etc. These series of particles may be used in combination of two or more as required.

  Moreover, the average particle diameter of the particle | grains to be used becomes like this. Preferably it is 5 micrometers or less, More preferably, it is the range of 0.1-3 micrometers. When the average particle diameter exceeds 5 μm, the surface roughness of the film becomes too rough, which may affect the surface shape of the molding surface to be transferred.

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

  The method for adding 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 for producing the polyester constituting each layer, but it is preferably added after completion of esterification or transesterification.

  In addition, the polyester film in the present invention contains conventionally known antioxidants, antistatic agents, heat stabilizers, ultraviolet absorbers, lubricants, dyes, pigments and the like as necessary in addition to the above-mentioned particles. Can do.

  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 from the viewpoint of mechanical strength, handling properties, and productivity. Is preferably in the range of 5 to 100 μm, more preferably 8 to 50 μm.

  As a film forming method of the film of the present invention, a generally known film forming method can be adopted, and there is no particular limitation. For example, when producing a biaxially stretched polyester film, the polyester raw material described above is first 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 an electrostatic application adhesion method or a liquid application adhesion method is preferably employed.

  Next, the obtained unstretched sheet is stretched in one direction by a roll or a 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. Next, the film is stretched in the direction perpendicular to the first-stage stretching direction at usually 70 to 170 ° C. and the stretching ratio is usually 2.5 to 7 times, preferably 3.0 to 6 times. Subsequently, a method of obtaining a biaxially oriented film by performing heat treatment at a temperature of 180 to 270 ° C. under tension or under relaxation within 30% is mentioned. In the above-described stretching, a method in which stretching in one direction is performed in two or more stages can be employed. In that case, it is preferable to carry out so that the draw ratios in the two directions finally fall within the above ranges.

  In the present invention, the simultaneous biaxial stretching method can be adopted for the production of the polyester film constituting the protective film. The simultaneous biaxial stretching method is a method in which the above-mentioned unstretched sheet is usually stretched and oriented in the machine direction and the width direction at a temperature controlled normally at 70 to 120 ° C., preferably 80 to 110 ° C. Is 4 to 50 times, preferably 7 to 35 times, and more preferably 10 to 25 times in terms of area magnification. Subsequently, heat treatment is performed at a temperature of 170 to 270 ° C. under tension or relaxation within 30% to obtain a stretched oriented film. With respect to the simultaneous biaxial stretching apparatus that employs the above-described stretching method, a conventionally known stretching method such as a screw method, a pantograph method, or a linear driving method can be employed.

  Next, formation of the release layer constituting the protective film in the present invention will be described. Regarding the release layer, it may be provided by in-line coating which treats the film surface during the process of forming the polyester film, or 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.

  In-line coating is a method of coating within the process of manufacturing a polyester film, and specifically, a method of coating at any stage from melt extrusion of a polyester to heat setting after stretching and winding up. 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 setting, and a film after heat setting and before winding.

  Although not limited to the following, for example, in sequential biaxial stretching, a method of stretching in the transverse direction after coating a uniaxially stretched film stretched in the longitudinal direction (longitudinal direction) is particularly excellent. According to such a method, film formation and mold release layer formation can be performed at the same time, so there is an advantage in manufacturing cost. In addition, in order to perform stretching after coating, the thickness of the mold release layer can be changed depending on the stretch ratio. The thin film coating can be performed more easily than the offline coating. Further, by providing a 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. Furthermore, in the production of a biaxially stretched polyester film, the film can be restrained in the longitudinal and lateral directions by stretching while gripping the film end with a clip, etc. High temperature can be applied while maintaining the properties. Therefore, since the heat treatment performed after coating can be performed at a high temperature that 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 adhered more firmly. And the migration of the release component to the photoresist layer can be prevented. Furthermore, it can be set as a firm release layer, and the performance and durability of the release layer can be improved. Therefore, as a method for forming the release layer on at least one side of the polyester film, a production method in which a coating solution 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 surface, and the release layer contains a long-chain alkyl group-containing compound.

  The release layer in the present invention is provided, for example, for imparting a release property 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 investigations, the inventors of the present invention have incorporated a long-chain alkyl group-containing compound into the release layer to maintain the release property with respect to the photoresist layer, and after removing the polyester film, the photoresist It has been found that there is no silicone migration in 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 for improving 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, preferably 8 or more, more preferably 12 or more carbon atoms. Examples of the alkyl group include hexyl group, octyl group, decyl group, lauryl group, octadecyl group, and behenyl group. 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. . In view of heat resistance and contamination, 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, and an acid anhydride.
Examples of the compound having such a reactive group 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 view of releasability and ease of handling.

  Examples of the compound having an alkyl group capable of reacting with the reactive group 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. Long chain alkyl group-containing acid chlorides such as decyl chloride, lauryl chloride, octadecyl chloride, and behenyl chloride, long chain alkyl group-containing amines, and long chain alkyl group-containing alcohols. Among these, long chain alkyl group-containing isocyanates are preferable, and octadecyl isocyanate is particularly preferable in consideration of releasability and ease of handling.

  In addition, a polymer compound having a long-chain alkyl group in the side chain can also be obtained by copolymerization of a long-chain alkyl (meth) acrylate polymer or a long-chain alkyl (meth) acrylate and 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. It is done.

  In the present invention, it is essential to use a long-chain alkyl group-containing compound in order to improve the mold releasability of the film, but a plurality of conventionally known release agents may be used in combination. Examples of conventionally known release agents include waxes, fluorine compounds, and silicone compounds. However, it is desirable that the release layer of the present invention is formed of a release agent of a non-silicone compound from the viewpoint that the silicone component may be transferred to the photoresist layer, which 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, even more preferably 1% by weight or less, and particularly preferably Means 0.5% by weight or less, and most preferably means not intentionally contained. Even if the silicone compound is not actively used, there is a possibility that contaminants derived from foreign substances, etc., and dirt adhering to the film manufacturing process line and apparatus 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 crosslinking agent in order to improve the strength of the release layer, the adhesion to the substrate, and the heat resistance.

  Examples of the crosslinking agent used in the present invention include melamine compounds, isocyanate compounds, oxazoline compounds, epoxy compounds, carbodiimide compounds, and the like. Among these crosslinking agents, it is preferable to use a melamine compound or an isocyanate compound from the viewpoint that the coating film strength is good. Furthermore, a melamine compound is preferable from the viewpoint of excellent release properties of the release layer. In addition, an isocyanate compound is particularly preferable from the viewpoint of excellent heat resistance of the release layer and little influence on the release property even when heat treatment is applied during processing. Moreover, these crosslinking agents may use 2 or more types together.

  The melamine compound is a compound having a melamine skeleton in the compound. For example, an alkylolized melamine derivative, a compound partially or completely etherified by reacting an alcohol with an alkylolated melamine derivative, and these Mixtures can be used. Examples of the alkylolation include methylolation, ethylolation, isopropylolation, n-butyroylation, and isobutyrololization. Among these, methylolation is preferable from the viewpoint of reactivity. Moreover, as alcohol used for etherification, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, isobutanol, etc. are used suitably. From the viewpoint of improving the coating film strength and improving the adhesion between the release layer and the substrate, it is preferably an alkylolated melamine derivative partially etherified, and is an alkylol etherified with methyl alcohol. It is more preferable. Therefore, a more preferable form is a 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. Moreover, as a melamine compound, either a monomer or a multimer more than a dimer may be sufficient, or a mixture thereof may be used. Further, a product obtained by co-condensing urea or the like with a part of melamine can be used, and a catalyst can be used to increase the reactivity of the melamine compound.

  The isocyanate compound is a compound having an isocyanate derivative structure represented by a blocked isocyanate having a structure in which an isocyanate group of an isocyanate compound as a precursor is protected with a blocking agent. Examples of the isocyanate include aliphatic isocyanate compounds, alicyclic isocyanate compounds, and aromatic isocyanate compounds. These isocyanate compounds are more preferably compounds having a plurality of isocyanate groups, that is, polyisocyanate compounds, from the viewpoint that they can be reacted to a higher degree and can improve the heat resistance of the release layer. Further, when an aqueous coating solution is used, it is more preferably a 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, lysine triisocyanate, 4-isocyanatomethyl-1,8-octamethylene diisocyanate, bis (2-isocyanatoethyl) 2-isocyanatoglutarate, or compounds derived from these isocyanate compounds be able to. Of these, hexamethylene diisocyanate is preferred because of its industrial availability.

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

  Examples of the aromatic polyisocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, or these isocyanate compounds. A compound etc. can be mentioned.

  Among these polyisocyanate compounds, aliphatic polyisocyanate compounds and alicyclic polyisocyanate compounds are preferable because of excellent weather resistance. Furthermore, among aliphatic polyisocyanate compounds, aliphatic polyisocyanate compounds derived from aliphatic diisocyanates are preferred. Among these, hexamethylene diisocyanate is particularly preferable. Moreover, these isocyanate compounds may be used independently and may use 2 or more types together.

  The block 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, heavy Examples thereof include a sulfite blocking agent. Among these, an active methylene blocking agent is preferable from the viewpoint that the peeling characteristics after heating are particularly difficult to change. Moreover, these blocking agents may use 2 or more types together.

  Examples of the active methylene-based blocking agent include isobutanoyl acetate, n-propanoyl acetate, n-butanoyl acetate, n-pentanoyl acetate, n-hexanoyl acetate, 2-ethylheptanoyl acetate, malonate, Examples thereof include acetoacetic acid esters and acetylacetone. Among them, isobutanoyl acetate, n-propanoyl acetate, n-butanoyl acetate, n-pentanoyl acetate, n-hexanoyl acetate, 2- Ethylheptanoyl acetate is preferable, more preferably isobutanoyl acetate, n-propanoyl acetate, n-pentanoyl acetate, and still more preferably isobutanoyl acetate. More specifically, examples of 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 include n-pentyl, n-hexyl isobutanoyl acetate, 2-ethylhexyl isobutanoyl acetate, phenyl isobutanoyl acetate, and benzyl isobutanoyl acetate. Of these, methyl isobutanoyl acetate and ethyl isobutanoyl acetate are preferred. Examples of n-propanoyl acetate include n-propanoyl methyl acetate, n-propanoyl ethyl acetate, n-propanoyl acetate isopropyl, n-propanoyl acetate n-butyl, n-propanoyl acetate t-butyl and the like. Among these, n-propanoyl methyl acetate and n-propanoyl ethyl acetate are preferable. Examples of n-pentanoyl acetate include n-pentanoyl methyl acetate, n-pentanoyl ethyl acetate, n-pentanoyl acetate isopropyl, n-pentanoyl acetate n-butyl, and n-pentanoyl acetate t-butyl. Among these, n-pentanoyl methyl acetate and n-pentanoyl ethyl acetate are preferable.

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

  Examples of the oxime blocking agent include formaldehyde oxime, acetoald oxime, acetone oxime, methyl ethyl ketoxime, and cyclohexanone oxime.

  Examples of the pyrazole-based blocking agent include pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole and the like. Examples of the alcohol blocking agent include methanol, ethanol, 2-propanol, n-butanol, sec-butanol, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol and the like. It is 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. Di-n-propylphenol, diisopropylphenol, isopropylcresol, di-n-butylphenol, di-t-butylphenol, di-sec-butylphenol, di-n-octylphenol, di-2-ethylhexylphenol, di-n- And 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 block agent include butyl mercaptan and dodecyl mercaptan.

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

  Examples of the acid imide blocking agent include succinimide and maleic imide.

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

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

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

  The blocked isocyanate compound used in the film of the present invention preferably contains a hydrophilic part in order to enhance the compoundability in water-based paints. As a method for adding a hydrophilic part to the blocked isocyanate compound, for example, a precursor is used. The method of making the isocyanate group of an isocyanate compound and the hydrophilic compound which has active hydrogen react is mentioned.

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

  Examples of the polyethylene glycol compound include monoalkoxy polyethylene glycol, polyethylene glycol, polyoxypropylene polyoxyethylene copolymer diol, polyoxypropylene polyoxyethylene block polymer diol, and the like. Monoalkoxy polyethylene glycols such as ethoxy polyethylene 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, for example, hydroxypivalic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, or polycaprolactone diol or polyether polyol using these as initiators. Derivatives, and salts thereof.

  Examples of the sulfonic acid group-containing compound include aminoethylsulfonic acid, ethylenediamino-propyl-β-ethylsulfonic acid, 1,3-propylenediamine-β-ethylsulfonic acid, N, N-bis (2-hydroxyethyl) -2. -Aminoethanesulfonic acid, and salts thereof.

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

  In addition, the crosslinking agent used for this invention is used by the design which makes it react in a drying process or a film forming process, and improves the performance of a mold release layer. It can be inferred that unreacted products of these crosslinking agents, compounds after the reaction, or mixtures thereof exist in the completed release layer.

  In 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 and transparency and to 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, methylcellulose, hydroxycellulose, starches and the like. . Among these, polyester resin, urethane resin, and acrylic resin are preferable, and polyester resin is more preferable in that it is easy to control releasability.

  The polyester resin includes, for example, those composed of the following polyvalent carboxylic acid and polyvalent hydroxy compound as main constituent components. 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-sodium sulfoisophthalic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, glutar Acid, succinic acid, trimellitic acid, trimesic acid, pyromellitic acid, trimellitic anhydride, phthalic anhydride, p-hydroxybenzoic acid, trimellitic acid monopotassium salt and ester-forming derivatives thereof can be used. As the polyvalent hydroxy compound, ethylene Recall, 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-xylylene glycol, bisphenol A-ethylene glycol adduct, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol Polytetramethylene glycol, polytetramethylene oxide glycol, dimethylolpropionic acid, glycerin, trimethylolpropane, sodium dimethylolethylsulfonate, potassium dimethylolpropionate, and the like can be used. One or more compounds may be appropriately selected from these compounds, 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. Usually, urethane resin is prepared by reaction of polyol and isocyanate. Examples of the polyol include polycarbonate polyols, polyester polyols, polyether polyols, polyolefin polyols, and acrylic polyols. These compounds may be used alone or in combination.

Polycarbonate polyols are obtained from a polyhydric alcohol and a carbonate compound by a dealcoholization reaction. Examples of the polyhydric alcohols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 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 Diol, neopentyl glycol, 3-methyl-1,5-pentanediol, 3,3-dimethylol heptane and the like can be mentioned. Examples of the carbonate compound include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, and ethylene carbonate. Examples of polycarbonate polyols obtained from these reactions include poly (1,6-hexylene) carbonate, poly (3- And methyl-1,5-pentylene) carbonate.

  Polyester polyols include polycarboxylic acids (malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid, etc.) or their acid anhydrides. Product and polyhydric alcohol (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-dimethyl-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, cyclohexane Diol, bishydroxymethylcyclohexane, dimethanolbenzene, bishydroxyethoxybenzene, alkyl dialkanolamine, lactone diol, etc.).

  Examples of 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 for obtaining the urethane resin include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, and tolidine diisocyanate, α, α, α ′, α ′. -Aliphatic diisocyanates having aromatic rings such as tetramethylxylylene diisocyanate, aliphatic diisocyanates such as methylene diisocyanate, propylene diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, dicyclohexyl Methanzi Cyanate, alicyclic diisocyanates such as isopropylidene dicyclohexyl diisocyanates. These may be used alone or in combination.

  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 an isocyanate 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. And glycols such as glycols. Examples of the chain extender having two amino groups include aromatic diamines such as tolylenediamine, xylylenediamine, 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 decane diamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, isopropylidenecyclohexyl-4,4′-diamine, 1,4-diaminocyclohexane, 1, 3-Bisaminomethylcyclohexa And alicyclic diamines such as

  The urethane resin may use a solvent as a medium, but preferably uses water as a medium. In order 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, and a water-soluble type. In particular, the self-emulsification type in which an ionic group is introduced into the structure of the urethane resin to form an ionomer is preferable because of excellent storage stability of the liquid and water resistance and transparency of the resulting coating layer. Examples of the ionic group to be introduced include various groups such as a carboxyl group, sulfonic acid, phosphoric acid, phosphonic acid, quaternary ammonium salt, and the like, and a carboxyl group is preferable. As a method for introducing a carboxyl group into a urethane resin, various methods can be taken in each stage of the polymerization reaction. For example, there are a method of using a carboxyl group-containing resin as a copolymer component during prepolymer synthesis, and a method of using a component having a carboxyl group as one component such as polyol, polyisocyanate, and chain extender. In particular, a method in which a desired amount of carboxyl groups is introduced using a carboxyl group-containing diol depending on the amount of this component charged is preferred. For example, dimethylolpropionic acid, dimethylolbutanoic acid, bis- (2-hydroxyethyl) propionic acid, bis- (2-hydroxyethyl) butanoic acid and the like are copolymerized with a diol used for polymerization of a urethane resin. Can do. The carboxyl group is preferably in the form of a salt neutralized with ammonia, amine, alkali metal, inorganic alkali or the like. Particularly preferred are ammonia, trimethylamine and triethylamine. In such a polyurethane resin, a carboxyl group from which the neutralizing agent has been removed in the drying step after coating can be used as a crosslinking reaction point by another crosslinking agent. Thereby, it is possible to further improve the durability, solvent resistance, water resistance, blocking resistance, and the like of the obtained release layer, as well as excellent stability in a liquid state before coating.

  The acrylic resin is a polymer composed of a polymerizable monomer including acrylic and methacrylic monomers. These may be either homopolymers or copolymers, and copolymers with polymerizable monomers other than acrylic and methacrylic monomers. Moreover, the copolymer of these polymers and other polymers (for example, polyester, polyurethane, etc.) is also included. For example, a block copolymer or a graft copolymer. 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 obtained by polymerizing a polymerizable monomer in a polyurethane solution or a polyurethane dispersion (sometimes a mixture of polymers) 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. Moreover, in order to improve adhesiveness with a base material more, it is also possible to contain a hydroxyl group and an amino group.

  The polymerizable monomer is not particularly limited, but particularly representative compounds include, for example, 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, monobutyl hydroxyl fumarate, monobutyl hydroxy itaconate Various hydroxyl group-containing monomers; various (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate; (Meth) acrylamide, Various nitrogen-containing compounds such as acetone acrylamide, N-methylol acrylamide or (meth) acrylonitrile; various styrene derivatives such as styrene, α-methylstyrene, divinylbenzene, vinyltoluene, and various vinyls such as vinyl propionate Esters; various silicon-containing polymerizable monomers such as γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, etc .; phosphorus-containing vinyl monomers; various vinyl halides such as vinyl chloride and biridene chloride Various conjugated dienes such as butadiene.

  As a ratio with respect to all the non-volatile components of the release layer constituting the protective film in the present invention, 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, and more preferably in the range of 10 to 10%. It is in the range of 90% by weight. If the amount is less than 3% by weight, sufficient release performance may not be obtained.

  When a crosslinking agent is used in combination with the release layer, when a melamine compound is used as the crosslinking agent, the ratio of the long-chain alkyl group-containing compound to the total nonvolatile 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 crosslinking agent, the ratio of the long-chain alkyl group-containing compound is preferably from 5 to 95% by weight, more preferably from 15 to 93% by weight, as a ratio to the total nonvolatile components of the release layer. A range of 25 to 90% by weight is particularly preferred.

  When a crosslinking agent is used in combination with the release layer constituting the protective film in the present invention, the crosslinking agent is preferably in the range of 97% by weight or less, more preferably 5 to 95% by weight as a ratio to the total nonvolatile components of the release layer. %, More preferably in the range of 10 to 90% by weight. By using in the above range, the heat resistance of the release layer can be improved, and sufficient release properties can be maintained even after heat treatment.

  When a melamine compound is used as the crosslinking agent, the ratio of the melamine compound to the total nonvolatile components of the release layer is preferably 5 to 90% by weight, more preferably 10 to 80% by weight, and 15 to 70% by weight. % Range is particularly preferred.

  When using an isocyanate compound for the crosslinking agent, the isocyanate compound is preferably in the range of 5 to 95% by weight, more preferably in the range of 7 to 85% by weight, as a ratio to the total nonvolatile components of the release layer. A range of 75% by weight is particularly preferred.

  The releasability of the release layer of the present invention depends on the type of material of the photoresist layer, but when expressed as a peel force for 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 peel strength of the release layer of the present invention after the heat treatment on the acrylic adhesive tape depends on the value of the peel strength before heating, but the peel strength after heating at 100 ° C. for 1 hour is preferably 1700 mN / cm or less, more preferably 1100 mN / cm or less, further preferably 850 mN / cm or less, and particularly preferably 750 mN / cm or less. By setting it within the above range, it is possible to peel the adhesive layer well even when heat treatment is applied. Moreover, 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, a layer containing an antistatic agent is preferable 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 0.001-1 μm, more preferably 0.005-0.5 μm, and still more preferably 0.01-0.2 μm. Range. When the film thickness exceeds 1 μm, the appearance of the coating film may be deteriorated and the coating film may be insufficiently cured. When the film thickness is less than 0.001 μm, sufficient releasability may not be obtained. .

  As long as the gist of the present invention is not impaired, particles may be used in combination with the formation of the release layer of the film of the present invention for the purpose of improving blocking properties and slipping properties.

  Furthermore, as long as it does not impair the gist of the present invention, the release layer is formed as necessary with an antifoaming agent, a coating improver, a thickener, an organic lubricant, an antistatic agent, an ultraviolet absorber, and an antioxidant. Agents, foaming agents, dyes, pigments and the like can be used in combination.

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

  When the release layer is provided by in-line coating, the above-described series of compounds is applied as an aqueous solution or water dispersion, and a coating solution adjusted to a solid content concentration of about 0.1 to 50% by weight is applied onto the polyester film. It is preferable to produce a protective film in the manner described above. Moreover, in the range which does not impair the main point of this invention, a small amount of organic solvents may be contained in the coating liquid for the purpose of improving dispersibility in water, improving film-forming properties, and the like. Only one type of organic solvent may be used, or two or more types may be used as appropriate.

  Examples of the method for forming the release layer of the present invention include gravure coating, reverse roll coating, die coating, air doctor coating, blade coating, rod coating, bar coating, curtain coating, knife coating, transfer roll coating, squeeze coating, 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 off-line coating, usually at 80 to 200 ° C. for 3 to 40 seconds, preferably 100. The heat treatment is preferably performed at ˜180 ° C. for 3 to 40 seconds as a guide.

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

  Further, irrespective of off-line coating or in-line coating, heat treatment and active energy ray irradiation such as ultraviolet irradiation may be used in combination as required. The polyester film constituting the protective film in the present invention may be subjected to surface treatment such as corona treatment or 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 pressure laminating on the photoresist layer.

Examples of the carrier film include a polyester film and a polypropylene film, among which a polyester film is particularly preferable. As a polyester film, the thing similar to the content as described in the polyester film of the protective film of this invention is mentioned.

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. Although it does not specifically limit as a monomer which has a polymerizable unsaturated group, A monomer which has one polymerizable unsaturated group, a monomer which has two polymerizable unsaturated groups, a polymerizable unsaturated group The monomer which has 3 or more is mentioned, These are used individually or in combination suitably.

  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 (meta). ) Acrylate, butyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 3-chloro-2 -Hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl acid phosphate, phthalic acid derivative half (meth) acrylate, N-methylol (meth) acrylamide and the like.

  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. Glycol di (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, phthalate Examples include acid diglycidyl ester di (meth) acrylate and hydroxypivalic acid-modified neopentyl glycol di (meth) acrylate. Among these, ethylene oxide-modified bisphenol A type di (meth) acrylate and ethylene oxide / propylene oxide modified bisphenol A type di (meth) acrylate are 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, dipentaerythritol penta ( And (meth) acrylate, tri (meth) acryloyloxyethoxytrimethylolpropane, glycerin polyglycidyl ether poly (meth) acrylate, and the like.

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

  As the monomer having a polymerizable unsaturated group, those having two polymerizable unsaturated groups and having a weight average molecular weight of 1500 or less, preferably 300 to 1200 are preferable, and in particular, ethylene oxide-modified bisphenol A 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, resulting in a decrease in resolving power and a decrease in fine line adhesion.

  Although it does not specifically limit as a polymer contained in the photosensitive resin composition, The polymer which consists of an acryl-type and a methacryl-type polymerizable monomer is mentioned. Either a homopolymer or a copolymer, or a copolymer with a polymerizable monomer other than an acrylic or methacrylic monomer may be used. Examples of polymerizable monomers include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid, or anhydrides and half esters thereof, methyl (meth) acrylate, and ethyl (meth) acrylate. , Propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, hydroxyethyl ( (Meth) acrylates such as (meth) acrylate, hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, acrylamide, methacrylamide, acrylonitrile, methacrylonitrile Styrene, alpha-methyl styrene, vinyl acetate, alkyl vinyl ether.

The weight average molecular weight of the above polymer is preferably 5,000 to 250,000, more preferably 10,000 to 200,000. When the weight average molecular weight is less than 5,000, the resin becomes too soft and the resin may bleed out when processed into a roll form as a photoresist film. When the weight average molecular weight 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. When the glass transition temperature is less than 30 ° C., the resin becomes so soft that the resin may bleed out when processed into a roll form as a photoresist film. When the glass transition temperature exceeds 150 ° C., it is used as a photoresist film. There is a possibility that the followability to the unevenness of the substrate surface at the time is lowered.

  A conventionally well-known thing is used as a photoinitiator 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 Benzophenone derivatives such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzoin isobutyl ether and other benzoin derivatives, anthraquinone, naphthoquinone and other quinone derivatives, 2-chlorothioxanthone, 2 -Thioxanthone derivatives such as methylthioxanthone and 2,4-diethylthioxanthone, dichloroacetophenone, 2,2-diethoxyacetophenone, 2,2-di Acetophenone derivatives such as rolo-4-phenoxyacetophenone, phenylglyoxylate, α-hydroxyisobutylphenone, dibenzoparone, 1- (4-isopropylphenyl) -2-hydroxy-2-methyl-1-propanone, 2-methyl- Propanone derivatives such as [4- (methylthio) phenyl] -2-morpholino-1-propanone, sulfone derivatives such as tribromophenylsulfone and 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) -1,3,5-triazine, etc. Triazine derivatives, acridine derivatives such as acridine and 9-phenylacridine, 2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,2'-biimidazole, 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 Cyphenyl) -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. Hexaarylbiimidazole derivatives such as tautomers covalently bonded at 1,2'-, 1,4'-, 2,4'-, etc. disclosed in Japanese Patent Publication No. 45-37377, etc. , Benzoylbenzoic acid, methyl benzoylbenzoate, benzyl Phenyl disulfide, benzyl dimethyl ketal, 2-methyl-1- [4- (methylthio) phenyl] -2-morifornopropan-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-propan-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-to Methylbenzoyl-diphenyl-phosphine oxide, bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium, etc. can give. 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.

  Other photosensitive resin compositions include amino resins such as melamine and thermal crosslinking agents such as isocyanate compounds, crystal violet, malachite green, malachite green lake, brilliant green, patent blue, methyl violet, Victoria blue, rose aniline. , Coloring dyes such as parafuchsin and ethylene violet, adhesion promoter, plasticizer, antioxidant, thermal polymerization inhibitor, solvent, surface tension modifier, stabilizer, chain transfer agent, antifoaming agent, flame retardant, etc. Additives can be added.

  In the case of preparing a photoresist film by providing a photosensitive resin composition on a carrier film, a method in which an organic solvent is mixed with the photosensitive resin composition so as to have a predetermined concentration is used. 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 coated on one side of a carrier film by a method such as a roll coater method or a bar coater method, and is usually 50 to 130 ° C. or in an oven where the temperature is gradually increased. A photoresist film is produced by drying to form a photoresist layer and covering with a protective film.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded. The measurement method and evaluation method used in the present invention are as follows.

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

(2) Measurement of average particle diameter (d50) The average particle diameter d50 is the average particle diameter 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. It was.

(3) Method for measuring film thickness of 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 “No. 31B” base material thickness 25 μm) was applied to the surface of the release layer of the polyester film provided with the release layer with a 2 kg rubber roller. The peel force after reciprocating was measured after standing at room temperature for 1 hour. For 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 peel strength after heating of release film Adhesive tape (Nitto Denko “No. 31B” base material thickness 25 μm) is applied to a 2 kg rubber roller on the release layer surface of a polyester film provided with a release layer. After one reciprocating pressure bonding, it was heated in an oven at 100 ° C. for 1 hour. Thereafter, the peel force after standing at room temperature for 1 hour was measured. For 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 photoresist layer As a carrier film, the polyester film described in Comparative Example 1 having a thickness of 16 μm was used. After drying, a 40 μm photoresist layer is formed, and the protective film of the present invention is placed thereon so that the release layer and the photoresist layer face each other, and then the photoresist film covered with the protective film by pressing is applied. Created. Then, the protective film was peeled off and the peelability was evaluated. Smooth peeling, no transfer to resist protective film, no scratch on resist surface, peeling is not smooth, peeling from resist is impossible, scratching resist surface What was done was made into x.

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

The polyester used in the examples and comparative examples was prepared as follows.
<Method for producing polyester (A)>
100 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol, 30 ppm of ethyl acid phosphate with respect to the resulting polyester, and 100 ppm of magnesium acetate tetrahydrate with respect to the resulting polyester as the catalyst at 260 ° C. in a nitrogen atmosphere at 260 ° C. The reaction was allowed to proceed. Subsequently, 50 ppm of tetrabutyl titanate was added to the resulting polyester, the temperature was raised to 280 ° C. over 2 hours and 30 minutes, the pressure was reduced to 0.3 kPa in absolute pressure, and melt polycondensation was further carried out for 80 minutes. A polyester (A) having 0.63 and an amount of diethylene glycol of 2 mol% was obtained.

<Method for producing 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. in a nitrogen atmosphere at 900 ppm with respect to the produced polyester. Subsequently, 3500 ppm of orthophosphoric 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. After 85 minutes of melt polycondensation, polyester (B) having an intrinsic viscosity of 0.64 and a diethylene glycol amount of 2 mol% was obtained.

<Method for producing polyester (C)>
In the production method of polyester (A), polyester (C) is obtained using the same method as the production method of polyester (A), except that 0.3 part by weight of silica particles having an average particle diameter of 2 μm is 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 compounds: (I)
To a four-necked flask, 200 parts of xylene and 600 parts of octadecyl isocyanate were added and heated with stirring. From the time when xylene began to reflux, 100 parts of polyvinyl alcohol having an average degree of polymerization of 500 and a degree of saponification of 88 mol% was added in small portions over a period of about 2 hours. After the addition of polyvinyl alcohol, the reaction was completed by further refluxing for 2 hours. When the reaction mixture was cooled to about 80 ° C. and added to methanol, the reaction product was precipitated as a white precipitate. This precipitate was filtered off, added with 140 parts of xylene, and heated to dissolve completely. After repeating the operation of adding methanol again to precipitate several times, the precipitate was washed with methanol and dried and ground.

・ Melamine compounds: (IIA)
Partially etherified melamine in which the ratio of methylol group to methoxy group is 1: 2.2
Active methylene block polyisocyanate: (IIB)
1000 parts of block polyisocyanate hexamethylene diisocyanate synthesized by the following method was stirred at 60 ° C., and 0.1 part of tetramethylammonium caprylate was added as a catalyst. After 4 hours, 0.2 part of phosphoric acid was added to stop the reaction, and an isocyanurate type polyisocyanate composition was obtained. 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 maintained at 80 ° C. for 7 hours. Thereafter, the reaction solution temperature was kept at 60 ° C., 35.8 parts of methyl isobutanoyl acetate, 32.2 parts of diethyl malonate, and 0.88 part of 28% methanol solution of sodium methoxide were added and kept for 4 hours. Block polyisocyanate obtained by adding 58.9 parts of n-butanol and maintaining the reaction solution temperature at 80 ° C. for 2 hours, and then adding 0.86 part of 2-ethylhexyl acid phosphate.

・ Polyester resin: (IIIA)
Water 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) Aqueous dispersion of 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) Emulsion 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 / dimethylolpropanoic acid = 12/19/18/21/25/5 (mol%).

Example 1:
A mixed raw material in which polyesters (A), (B), and (C) were mixed at a ratio of 77%, 3%, and 20%, respectively, was used as a raw material for the outermost layer (surface layer), and polyesters (A) and (B) were each 97 %, 3% of the mixed raw material is used as an intermediate layer raw material, each is supplied to two extruders, melted at 285 ° C., and then on a cooling roll set at 40 ° C. Coextruded and cooled and solidified in a layer structure of layers (surface layer / intermediate layer / surface layer = 1: 6: 1 discharge amount) to obtain an unstretched sheet. Next, the film was stretched 3.4 times in the longitudinal direction at a film temperature of 85 ° C. using the difference in peripheral speed of the roll, and then the coating solution 1 shown in Table 1 below was applied to one side of the longitudinally stretched film, which was led to a tenter. After stretching 4.0 times at 100 ° C in the transverse direction and heat-treating at 230 ° C, it is relaxed by 2% in the transverse direction, and a release layer having a coating layer thickness (after drying) of 0.03 μm on one side is formed. A protective film having a thickness of 16 μm was obtained. When the obtained protective film was evaluated, the initial release property and the release property after heating were good, and the film was also good in peelability from the photoresist layer. The properties of this film are shown in Table 2 below.

Examples 2 to 23:
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 composition shown in Table 1 in Example 1. As shown in Table 2, the finished protective film had good initial releasability, releasability after heating, and good releasability from the photoresist layer.

Comparative Example 1:
In Example 1, it manufactured similarly to Example 1 except not providing a mold release layer, and obtained the protective film. When the completed protective film was evaluated, it was as shown in Table 2. It was a film having poor release properties of the release layer and inferior peelability to the photoresist layer.

Comparative Examples 2-4:
In Example 1, it manufactured like Example 1 except having changed the application agent composition of a mold release layer into the application agent composition shown in Table 1, and obtained the protective film. When the completed protective film was evaluated, it was as shown in Table 2. It was a film having poor release properties of the release layer and inferior peelability to the photoresist layer.

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

Claims (1)

A protective film for a photoresist, comprising a release layer on at least one surface of a polyester film, wherein the release layer contains a long-chain alkyl group-containing compound.