TWI688616B - Protective film for dry film photoresist and photosensitive resin laminate - Google Patents

Abstract

As a protective film for dry film photoresist, there is provided a protective film having good release properties, antistatic properties, adhesion, and winding characteristics, and a photosensitive resin laminate in which the protective film is laminated.

On one side of the polyester film, there is a coating layer formed by a coating liquid containing a compound containing a long-chain alkyl group and an antistatic agent and acrylic resin or polyvinyl alcohol, the surface of the coating layer A dry film resist protective film having a maximum protrusion height (Rt) of 0.1 to 1.0 μm, and a photosensitive resin laminate having a structure in which the protective film is laminated on the surface of the photosensitive resin layer formed on the base film.

Description

Protective film for dry film photoresist and photosensitive resin laminate

The present invention relates to a protective film constituting a photosensitive resin laminate used in a step of manufacturing a dry film photoresist (hereinafter sometimes simply referred to as DFR) of a semiconductor printed circuit board and the like, and a photosensitive resin laminate.

Conventionally, the photosensitive resin laminate system used in the dry film photoresist (DFR) step has a laminate structure of base film/photosensitive resin layer/protective film.

The DFR step generally consists of peeling off the protective film composed of the aforementioned laminate, laminating the photosensitive resin on the copper foil substrate, placing a pattern mask on the base film, and exposing the photosensitive resin layer from the base film side by The manufacturing process of peeling off the base film for development and forming a circuit on the substrate.

In this way, a pattern mask is placed on the base film, and by exposure with ultraviolet rays or the like, in order to draw a circuit image, moderate light transmittance and smoothness in the base film become necessary. Therefore, as the base film, a polyester film with good UV transparency, excellent transparency, and good surface smoothness is used.

On the other hand, as the protective film, a polyethylene film is generally used. The film protects the photosensitive resin layer, while the base film/photosensitive resin layer/protection When the laminate composed of the protective film is rolled into a roll shape, the base film and the photosensitive resin layer are adhered (or adhered) between the back surface of the base film and the photosensitive resin composition layer, which also has a so-called block prevent. Therefore, the protective film must have a moderate release property.

When the peeling force of the protective film is too strong, a winding deviation or the like occurs when the laminate is rolled into a roll shape, which causes damage to the photosensitive resin layer. On the other hand, when the peeling force of the protective film is too weak, the peeling of the protective film from the photosensitive resin layer is likely to occur when the protective film does not need to be peeled off originally.

After the protective film is peeled off, it can no longer be used and must be disposed of. Patent documents 1 to 3 disclose the function of providing a protective film to the base film, without using a laminate of the protective film.

Patent Documents 1 and 2 disclose that on one side of a base film constituting a base film, a layer method of extruding medium-density polyethylene is laminated at a thickness of 15 μm, and a release layer is provided on the other side of the base film. A method of providing a photosensitive resin composition layer on one side.

However, the thickness of the release layer composed of medium-density polyethylene is increased, the amount of polyethylene consumed is increased and the cost is high, the laminate roll also becomes larger and heavier, and the operability is reduced, and the subsequent workability is also reduced.

In addition, Patent Documents 1 to 3 disclose that on one side of a base film constituting a base film, a polyethyleneimine alkyl modified body dissolved in an organic solvent is applied to a thickness of 0.1 μm, and a release layer is provided A method of providing a photosensitive resin composition layer on the other surface of the base film. However, in addition to the peel strength being too high, the stripping layer is also insufficiently stable against the peel strength of temperature changes.

In recent years, along with the further miniaturization of electronic devices, a higher density of printed wiring boards has been required, and further thinning of conductor patterns formed on the surface of insulating substrates has become an urgent need.

Therefore, as a protective film, fluctuations in the thickness of the polyethylene film or a large amount of fish eyes have become one of the main factors that make it difficult to further increase the density of printed wiring boards.

That is, dry film photoresist, after drying the photoresist layer coated on the base film, although the protective film is laminated on the photoresist layer to produce, but when the protective film is laminated, the light When the photoresist is soft and there are irregularities on the surface of the protective film due to fish eyes, this is transferred to the photoresist layer to make the surface of the photoresist layer uneven, causing photoresist to the insulating substrate ( The poor adhesion of the photoresist layer results in a defect in the conductor pattern.

In addition, although the polyethylene film is formed by melt extrusion, it is extremely difficult to filter with a high-performance filter during extrusion due to its high melt viscosity. The problem of fisheyes in the formed sheet is inevitable and completely It is very difficult to remove fish eyes.

Furthermore, it is difficult to obtain a uniform thickness in the general film forming method of polyethylene film, that is, the inflation method. Even if the thickness is oscillating, there is an unavoidable situation.

Accordingly, it is difficult to use polyethylene as a protective film in response to the demand for higher density of printed wiring boards.

On the other hand, Patent Document 4 describes that a polyester film for dry film photoresist using a polyester film is used as a substitute for a polyethylene film. However, for In order to ensure the mold release, if the polyester film is obtained with the same flexibility as the polyethylene film, the mold release agent is applied to give the mold release, and the long-chain aliphatic dicarboxylic acid and other copolymerization components are blended and/ Or polyolefin to give flexibility. The film described in the above-mentioned publication has insufficient release properties due to the coating layer, so the base film must be given flexibility.

Furthermore, the protective film is liable to generate static electricity due to contact friction or peeling during the processing step or use of the product, and it is easy to attach dust or small garbage. Therefore, there is a risk of contamination or foreign matter mixing in the step. Therefore, a method of applying a layered antistatic agent on the surface of a polyester film (patent document 5), etc. has been proposed for the purpose of aversion to mixing of foreign materials or charging.

Prior technical literature Patent Literature

Patent Document 1: Japanese Patent No. 2882953

Patent Document 2: Japanese Patent No. 3920094

Patent Document 3: Japanese Patent Laid-Open No. 2003-191424

Patent Document 4: Japanese Patent Laid-Open No. 6-297565

Patent Literature 5: Japanese Patent Laid-Open No. 7-26223

The present invention has been completed in view of the above-mentioned facts, and this problem has been solved as a protective film for dry film photoresist, which provides a protective film with good release properties, antistatic properties, adhesion, and winding characteristics, and lamination of the protection Membrane Photosensitive resin laminate.

In view of the above-mentioned conditions, the present inventors have made intensive studies and found that a protective film composed of a specific structure can easily solve the above-mentioned problems, and finally completed the present invention.

That is, the gist of the present invention is a protective film for dry film photoresist, which is characterized in that it is composed of a compound containing a long-chain alkyl group and an antistatic agent, and acrylic resin or polyethylene on one side of the polyester film. A coating layer formed by an alcohol coating liquid, and the maximum protrusion height (Rt) of the surface of the coating layer is 0.1 to 1.0 μm, and a photosensitive resin laminate having a photosensitive layer formed on a base film The protective resin layer is laminated on the surface of the protective resin layer.

The protective film for dry film photoresist of the present invention (hereinafter simply referred to as "protective film") is the release property of the protective film, the antistatic property of the protective film, the adhesion to the copper foil of the photosensitive resin layer, as a photosensitive The winding properties of the resin layer laminate are good, and its industrial value is high.

30‧‧‧Photosensitive resin laminate

11‧‧‧Polyester film

12‧‧‧Coated layer

20‧‧‧Protection film

13‧‧‧Photosensitive resin layer

14‧‧‧ Base film

[Fig. 1] A schematic cross-sectional view showing a photosensitive resin laminate of the present invention.

The polyester film constituting the protective film of the present invention may have a single-layer structure or a laminated structure. For example, in addition to the two-layer and three-layer structures, as long as it does not exceed the gist of the present invention, it may be a multilayer of four or more layers, not Specially limited.

The polyester used in the polyester film may be a homopolyester or a copolymerized polyester. In the case of a homopolyester, it is preferably obtained by polycondensation of an aromatic dicarboxylic acid and an aliphatic diol. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalene dicarboxylic acid. Examples of the aliphatic diols include ethylene glycol, diethylene glycol, and 1,4-cyclohexanedimethanol. Wait. As a representative polyester, polyethylene terephthalate (PET) and the like are exemplified. On the other hand, examples of the dicarboxylic acid component of the copolymerized polyester include isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalene dicarboxylic acid, adipic acid, sebacic acid, and oxy One or more types of carboxylic acids (for example, P-oxybenzoic acid, etc.), and examples of the diol component include ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, and 1,4-cyclohexanedimethanol. , Neopentyl glycol, etc. one or more. In any case, the so-called polyester in the present invention refers to a polymer of polyethylene terephthalate and the like which is usually 60 mol% or more, preferably 80 mol% or more in ethylene terephthalate units ester.

In the polyester layer, it is preferable to blend particles with the main purpose of imparting slipperiness. The type of the particles to be blended is not particularly limited as long as the particles can impart slidability. Specific examples include silicon dioxide, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, and phosphoric acid. Particles of magnesium, clay, alumina, titanium oxide, etc. In addition, heat-resistant organic particles described in Japanese Patent Laid-Open No. 59-5216, Japanese Patent Laid-Open No. 59-217755, etc. can be used. Examples of other heat-resistant organic particles include thermosetting urea resin, thermosetting phenol resin, thermosetting epoxy resin, and benzoguanamine resin. Furthermore, in the polyester production step, precipitated particles that precipitate and finely disperse a part of a metal compound such as a catalyst may also be used.

On the other hand, the shape of the particles used is not particularly limited, and any of spherical, block, rod, and flat shapes can be used. In addition, the hardness, specific gravity, color, etc. are not particularly limited. These series of particles can be used in combination of two or more types if necessary.

In addition, the average particle diameter of the particles used is usually 0.01 to 3 μm, preferably 0.01 to 1 μm. If the average particle size is less than 0.01 μm, the particles may easily aggregate and the dispersibility is insufficient. On the other hand, if the average particle size exceeds 3 μm, the surface roughness of the film becomes too coarse. Layers, etc. have problems.

Furthermore, the content of particles in the polyester layer is usually 0.001 to 5% by weight, preferably 0.005 to 3% by weight. When the particle content is less than 0.001% by weight, the slipperiness of the film may be insufficient. On the other hand, when the content exceeds 5% by weight, the transparency of the film may be insufficient.

The method of adding particles to the polyester layer is not particularly limited, and a conventionally known method can be used. For example, although it can be added at any stage of manufacturing the polyester constituting each layer, it is preferably the stage of esterification, Alternatively, the polycondensation reaction can be carried out after the transesterification reaction is completed.

In addition, by using a kneading extruder with a vent, a method of mixing a slurry of particles dispersed in ethylene glycol, water, or the like with polyester raw materials, or using a kneading extruder, mixing the dried particles and polyester The method of raw materials is carried out.

In addition, in addition to the above-mentioned particles, conventionally known antioxidants, antistatic agents, heat stabilizers, lubricants, dyes, pigments, etc. may be added to the polyester film if necessary.

The thickness of the polyester film is usually 9 to 25 μm, preferably 9 to 20 μm in order to improve the operability during use. When the film thickness is less than 9 μm, the film strength may be insufficient and the operability may be reduced. On the other hand, when it exceeds 25 μm, a protective film is used, and when it becomes a photosensitive resin laminate, the thickness of the protective film is too thick, which may reduce workability.

Next, although the production examples of the polyester film are specifically described, they are not limited to those of the following production examples.

First, using the polyester raw material described above, the molten sheet extruded from the die is cooled and solidified by a cooling roll, and a method of obtaining an unstretched sheet is preferred. In this case, in order to improve the flatness of the sheet, it is necessary to improve the adhesion between the sheet and the rotating cooling roller, and it is preferable to use the electrostatic addition adhesion method and/or the liquid coating adhesion method. Next, the resulting unstretched sheet is stretched in the biaxial direction. In this case, first, the aforementioned unstretched sheet is stretched in a single direction by a roll or tenter stretching machine. Stretching temperature is usually 70~120℃, preferably 80~110℃, stretching ratio It is usually 2.5 to 7 times, preferably 3.0 to 6 times. Secondly, the stretching temperature perpendicular to the stretching direction of the first stage is usually 70 to 170°C, and the stretching ratio is usually 3.0 to 7 times, preferably 3.5 to 6 times, and more preferably 5.0 to 6 times. Then, heat treatment is performed at a temperature of 180 to 270°C under tension or within 30% of relaxation to obtain a biaxially oriented film. In the above-mentioned stretching, a method of stretching in one direction in two or more stages may also be used. In this case, it is preferable that the final stretch ratio in the two directions be carried out so as to fall within the above range.

In addition, regarding the production of the polyester film, the simultaneous biaxial stretching method may also be used. Simultaneous biaxial stretching method is a method in which the aforementioned unstretched sheet is controlled at a temperature of usually 70 to 120°C, preferably 80 to 110°C, and stretched in the machine direction and the width direction to align it, As the stretching magnification, the area magnification is usually 4 to 50 times, preferably 7 to 35 times, and more preferably 10 to 25 times. Then, heat treatment is performed at a temperature of 170 to 250° C. under tension or within 30% of relaxation to obtain a stretch alignment film. Regarding the simultaneous biaxial stretching device using the above-mentioned stretching method, a spiral method, a pantograph method, a linear driving method, etc., which are known from the past, can be used.

Furthermore, in the above-mentioned stretching step of the polyester film, the surface of the film can be treated, which is a so-called coating stretching method (inline coating). When the coating layer is provided on the polyester film by the coating and stretching method, it can be coated simultaneously with the stretching, and at the same time, the thickness of the coating layer can be thinned according to the stretching ratio, and a suitable film can be manufactured as Polyester film.

In the present invention, it will have Compound, antistatic agent, and coating layer formed with a coating solution of acrylic resin or polyvinyl alcohol are required.

In order to impart release properties and antistatic properties to the coating film at the same time, when using a release agent and an antistatic agent together, the transparency may deteriorate everywhere. As a result of various studies conducted by the present inventors, it has been found that by adding at least one of acrylic resin or polyvinyl alcohol, transparency is improved, and for the first time, a film with higher adaptability than a protective film or the like is made.

As a protective film, the coating layer is provided to improve the appropriate film release performance and to impart antistatic properties.

The long-chain alkyl group-containing compound used in the formation of the coating layer is used to improve the film release property.

The long-chain alkyl compound refers to a compound having a linear or branched alkyl group having a carbon number of usually 6 or more, preferably 8 or more, and more preferably 12 or more. Examples of the alkyl group include hexyl, octyl, decyl, lauryl, octadecyl, and behenyl. Examples of the compound having an alkyl group include various long-chain alkyl-containing polymer compounds, long-chain alkyl-containing amine compounds, long-chain alkyl-containing ether compounds, and long-chain alkyl-containing quaternary ammonium salts. Wait. In consideration of heat resistance and pollution, a polymer compound is preferred. In addition, from the viewpoint of effectively obtaining mold release properties, 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 refers to a polymer obtained by reacting a polymer having a reactive group with a compound having an alkyl group that can react with the reactive group. As said reactive group, a hydroxyl group, an amine group, a carboxyl group, an acid anhydride, etc. are mentioned, for example.

Examples of compounds having such reactive groups include polyvinyl alcohol, polyethyleneimine, polyvinylamine, reactive group-containing polyester resins, and reactive group-containing poly(meth)acrylic resins. Among these, polyvinyl alcohol is preferred when considering mold release properties or ease of handling.

Examples of the compound having an alkyl group that can react with the above-mentioned reactive group include hexyl isocyanate, octyl isocyanate, decyl isocyanate, lauryl isocyanate, octadecyl isocyanate, and behenyl isocyanate. Acid chlorides containing long-chain alkyl groups such as long-chain alkyl isocyanates, hexyl chloride, octyl chloride, decyl chloride, lauryl chloride, octadecyl chloride, behenyl chloride, etc. Compounds, amines containing long-chain alkyls, alcohols containing long-chain alkyls, etc. Among these, when considering the mold release property or ease of handling, an isocyanate containing a long-chain alkyl group is preferred, and octadecyl isocyanate is particularly preferred.

In addition, a polymer compound having a long-chain alkyl group in the side chain can be easily obtained by a long-chain alkyl (meth)acrylate polymer or a long-chain alkyl (meth)acrylate and other vinyl-containing monomers. Obtained by copolymerization. Examples of the long-chain alkyl (meth)acrylate include hexyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, Octadecyl (meth)acrylate, behenyl (meth)acrylate, etc.

In addition, in the present invention, in order to improve the release property of the film, although it is necessary to use a compound containing a long-chain alkyl group, in addition to this, a plurality of conventionally known mold release agents may be used in combination. Examples of conventionally known mold release agents include waxes, fluorine compounds, and silicone compounds.

Examples of the antistatic agent used in the formation of the coating layer include ionic conductive high molecular compounds such as compounds containing ammonium groups, polyether compounds, sulfonic acid compounds, and betaine compounds, or polyacetylene and polyphenylene , Polyaniline, polypyrrole, polyisothiindene, polythiophene and other π electron conjugated polymer compounds. These are used to impart antistatic properties to the film. Among these, ion-conductive polymer compounds are preferred, and compounds containing ammonium groups are particularly preferred.

The π-conjugated conductive polymer, for example, a coating layer formed of polythiophene or a coating solution containing polyaniline, is generally not suitable for optical applications requiring transparency due to strong coloration. In addition, π-conjugated conductive polymer coatings are generally more expensive than ion conductive coatings. From the viewpoint of manufacturing cost, ion conductive antistatic agents are suitable.

The compound containing an ammonium group refers to a compound having an ammonium group in the molecule, preferably a polymer compound having an ammonium group. For example, a polymer containing an ammonium group and a monomer having an unsaturated double bond as components can be used.

As a specific example of the polymer, for example, a polymer having a constituent element represented by the following formula (1) or the following formula (2) as a repeating unit can be cited. These homopolymers or copolymers, and further, copolymerizing other plural components may also be used. From the viewpoint of improving the compatibility with other materials or the transparency of the obtained coating film, a polymer having the constituent element represented by the following formula (1) as a repeating unit is preferable. Moreover, from the viewpoint of the height of the antistatic performance obtained or the heat resistance, it is preferable to express the following formula (2) The constituent element is a polymer that has repeating units.

In the above formula (1), R ² is -O- or -NH-, R ³ is an alkylene group, or other structure that can form the structure of formula (1), R ¹ , R ⁴ , R ⁵ , R ⁶ are respectively It is a hydrogen atom, an alkyl group, a phenyl group, etc. These alkyl groups and phenyl groups may be substituted with the groups shown below. Substitutable groups such as hydroxy, amide, ester, alkoxy, phenoxy, naphthoxy, thioalkoxy, thiophenoxy, cycloalkyl, trialkylammonium alkyl, cyano , Halogen, etc.

In the above formula (2), R ¹ and R ² are independently a hydrogen atom, an alkyl group, a phenyl group, etc., and these alkyl groups and phenyl groups may be substituted with the groups shown below. Substitutable groups such as hydroxy, amide, ester, alkoxy, phenoxy, naphthoxy, thioalkoxy, thiophenoxy, cycloalkyl, trialkylammonium alkyl, cyano , Halogen, etc. Furthermore, R ¹ and R ² may be chemically bonded, and examples include -(CH ₂ ) _m -(m=integer of 2 to 5), -CH(CH ₃ )CH(CH ₃ )-, -CH= CH-CH=CH-, -CH=CH-CH=N-, -CH=CH-N=C-, -CH ₂ OCH ₂ -, -(CH ₂ ) ₂ O(CH ₂ ) ₂ -, etc.

When the constituent element represented by the above formula (1) is used as a polymer in a repeating unit, from the viewpoint of improving the compatibility with other materials, improving the transparency of the obtained coating film, or further improving the release property , Preferably copolymerized with other repeating units. Other repeating units include, for example, alkyl acrylate such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate Alkyl methacrylates such as esters.

When the constituent element represented by the above formula (2) is used as a polymer having repeating units, it is preferable to copolymerize with other repeating units from the viewpoint of suppressing the decrease in release property. Other repeating units include, for example, the above-mentioned acrylamide such as alkyl acrylate or methacrylate, n-methylol acrylamide.

In addition, from the viewpoint of further improving antistatic performance, a homopolymer having the constituent element represented by the above formula (2) as a repeating unit is preferred.

X- in the above formulas (1) and (2) can be appropriately selected within a range that does not impair the gist of the present invention. For example, halogen ion, sulfonate, Phosphate, nitrate, alkylsulfonate, carboxylate, etc.

The polymer having the constituent elements represented by the above formula (1) is preferably excellent in transparency of the obtained coating layer. However, in the coating stretching method, the heat resistance may be deteriorated. In the coating stretching method, X- is not preferable to halogen.

The component represented by the above formula (2) or the compound having another ammonium salt group in the polymer skeleton is preferably excellent in heat resistance.

Moreover, copolymerizing the constituent elements represented by the above formulas (1) to (2) and the polymer containing (meth)acrylate of polyethylene glycol, the structure becomes soft, and when coating is stretched, excellent uniformity is obtained The coating layer is preferred.

Or even if the (meth)acrylate polymer containing polyethylene glycol is contained in the coating liquid and applied, the coating layer with excellent uniformity can be obtained in the same way

Examples of the polyethylene glycol-containing (meth)acrylate specifically include polyethylene glycol monoacrylate, polypropylene glycol monoacrylate, and polyethylene glycol diacrylate (preferably polyethylene diacrylate). (The degree of polymerization of the alcohol unit is in the range of 4 to 14), polypropylene glycol diacrylate, polytetramethylene glycol diacrylate, poly(ethylene glycol-tetramethylene glycol) diacrylate, poly(propylene glycol -Tetramethylene glycol) diacrylate, polyethylene glycol-polypropylene glycol-polyethylene glycol diacrylate, polypropylene glycol-polybutylene glycol monomethacrylate, methoxypolyethylene glycol monomethyl Acrylate, methoxypolyethylene glycol monoacrylate, octoxy polyethylene glycol-polypropylene glycol monomethacrylate, octoxy polyethylene glycol-polypropylene glycol monoacrylate, lauryl oxypolyacrylate Ethylene glycol monomethacrylate, lauryl oxypolyethylene glycol monoacrylate, Stearyloxy polyethylene glycol monomethacrylate, stearyl polyethylene glycol monoacrylate, allyloxy polyethylene glycol monomethacrylate, allyloxy polyethylene glycol monoacrylate Ester and other polymers as starting materials.

In addition, the number average molecular weight of the compound containing an ammonium group is usually 1,000 to 500,000, preferably 2,000 to 350,000, and more preferably 5,000 to 200,000. When the molecular weight is less than 1,000, the strength of the coating film may be weakened or the heat resistance stability may be deteriorated. In addition, when the molecular weight exceeds 500,000, the viscosity of the coating liquid may be increased, or the handleability or coating property may be deteriorated.

Although at least one of acrylic resin and polyvinyl alcohol is used for forming the coating layer, this is used to improve the transparency of the film.

The acrylic resin is a polymer composed of polymerizable monomers having carbon-carbon double bonds represented by monomers of acrylic and methacrylic systems. These can be either homopolymers or copolymers. In addition, copolymers of these polymers and other polymers (such as polyester and polyurethane) are also included. Examples are block copolymers and graft copolymers. Alternatively, it also includes a polymer obtained by polymerizing a polymerizable monomer having a carbon-carbon double bond in a polyester solution or polyester dispersion liquid (as the case may be, a mixture of polymers). Similarly, it also includes a polymer obtained by polymerizing a polymerizable monomer having a carbon-carbon double bond in a polyurethane solution or a polyurethane dispersion (as the case may be, a mixture of polymers). Similarly, it also includes a polymer obtained by polymerizing another polymer solution or a polymerizable monomer having a carbon-carbon double bond in the dispersion liquid (as the case may be, a polymer mixture). In addition, it may contain a hydroxyl group or an amine group. From suppression due to coating film From the viewpoint of deterioration in transparency, it is preferable to contain a hydroxyl group.

The polymerizable monomer having the above-mentioned carbon-carbon double bond is not particularly limited, but particularly as a representative compound, for example, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, and horse Various carboxyl-containing monomers of lysic acid and citraconic acid, and salts of these; such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyrate (Meth)acrylate, monobutyl hydroxyfumarate, monobutyl hydroxyitaconic acid esters containing various hydroxyl-containing monomers; such as methyl (meth) acrylate, ethyl (meth) Various (meth)acrylates of acrylate, propyl (meth)acrylate, butyl (meth)acrylate, lauryl (meth)acrylate; such as (meth)acrylamide, diacetone Various nitrogen-containing compounds such as acrylamide, N-methylolacrylamide or (meth)acrylonitrile; such as various styrene derivatives of styrene, α-methylstyrene, divinylbenzene, vinyltoluene 1. Various vinyl esters of vinyl propionate; various polymerizable monomers containing silicon such as γ-methacryloxypropyltrimethoxysilane, ethylene trimethoxysilane, etc.; vinyl monomers containing phosphorus Classes; various halogenated ethylenes such as chlorinated ethylene and vinylidene chloride; various conjugated dienes such as butadiene.

When the acrylic resin contains hydroxyl groups, the hydroxyl value of the acrylic resin is usually 2 to 100 mgKOH/g, preferably 5 to 50 mgKOH/g. When the hydroxyl value is within the above range, the coating appearance and transparency are improved.

The so-called polyvinyl alcohol is a compound having a polyvinyl alcohol moiety, for example, it also includes partial acetalization or butyraldehyde relative to polyvinyl alcohol In order to convert it into a compound, conventionally known polyvinyl alcohol can be used. Although the degree of polymerization of polyvinyl alcohol is not particularly limited, it is usually 100 or more, preferably 300 to 40,000. When the degree of polymerization is less than 100, the water resistance of the coating layer may be reduced. Although the degree of saponification of polyvinyl alcohol is not particularly limited, it is usually 70 mol% or more, preferably 70-99.9 mol%, more preferably 80-97 mol%, and particularly preferably 86-95 mol. % Range.

In the formation of the coating layer, various polymers or crosslinking agents other than acrylic resin or polyvinyl alcohol may be used in combination.

Specific examples of the polymer include polyester resin, urethane resin, polyalkylene glycol, polyalkylene imine, methyl cellulose, hydroxy cellulose, starch, and the like.

The polyester resin includes, for example, those composed of the following polycarboxylic acids and polyhydroxy compounds as main constituents. That is, as the polycarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, phthalic acid, 4,4′-diphenyl dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid and 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, 2-potassium sulfoterephthalic acid, 5 -Sodium sulfoisophthalic acid, adipic acid, azelaic acid, sebacic acid, dodecane dicarboxylic acid, glutaric acid, succinic acid, trimellitic acid, trimesic acid, pyromellitic acid, Trimellitic anhydride, phthalic anhydride, p-hydroxybenzoic acid, monopotassium trimellitate, and ester-forming derivatives of these, etc. As the polyhydroxy compound, ethylene glycol and 1,2-propanediol can be used , 1,3-propanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 2-methyl-1,5-pentanediol, neopentyl glycol, 1 ,4- Cyclohexane dimethanol, p-stubble glycol, bisphenol A-ethylene glycol adduct, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly Oxidized tetramethylene glycol, dimethylolpropionic acid, glycerin, trimethylolpropane, sodium dimethylolethanesulfonate, potassium dimethylolpropionate, etc. From these compounds, one or more can be appropriately selected, and the polyester resin can be synthesized by a conventional condensation polymerization reaction.

The urethane resin refers to a polymer compound having an urethane bond in the molecule. Urethane resins are usually made by the reaction of polyols and isocyanates. Examples of the polyol include polycarbonate polyols, polyester polyols, polyether polyols, polyolefin polyols, and acrylic polyols. These compounds may be used alone or in plural.

Polycarbonate polyols are obtained from polyols and carbonate compounds by dealcoholization. Examples of the polyhydric alcohols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5. -Pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,7-heptanediol, 1,8-octanediol, 1, 9-nonanediol, 1,10-decanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, etc. Examples of the carbonate compound include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, and ethyl carbonate. Examples of the polycarbonate-based polyols obtained by these reactions include poly(1 , 6-hexyl) carbonate, poly(3-methyl-1,5-pentyl) carbonate, etc.

Examples of polyester polyols include polycarboxylic acids (malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid). Acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid, etc.) or their anhydrides and polyols (ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, triethylene glycol Propylene glycol, butylene glycol, 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 Alcohol, 2-butyl-2-hexyl-1,3-propanediol, cyclohexanediol, bishydroxymethylcyclohexane, dimethanolbenzene, bishydroxyethoxybenzene, alkyl dialkanolamine, Those obtained by the reaction of lactonediol, etc.).

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

Examples of the polyisocyanate compound used to obtain the urethane resin include methylenediphenyl diisocyanate, stubble diisocyanate, methylene diphenyl diisocyanate, phenylenediisocyanate, and naphthalene diisocyanate. , Aromatic diisocyanates such as Tolidine diisocyanate, α,α,α',α'-Tetramethyl stubble diisocyanate and other aliphatic diisocyanates with methylene diisocyanate, methylene diisocyanate , Aliphatic diisocyanate such as propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, Isophorone diisocyanate, dicyclohexylmethane diisocyanate, diisopropylidene di Cyclohexyl diisocyanate, alicyclic diisocyanate, etc. These can be used alone or in combination.

When synthesizing the urethane resin, a chain extender can be used. As the chain extender, if it has two or more reactive groups that react with isocyanate groups, it is not particularly limited. A chain extender with hydroxyl or amine groups.

Examples of the chain extender having two hydroxyl groups include aliphatic diols such as ethylene glycol, propylene glycol, and butylene glycol, aromatic diols such as diols, and dihydroxyethoxybenzene, and neopentyl glycol. Glycols such as hydroxypivalate are called ester diols. In addition, examples of the chain extender having two amine groups include aromatic diamines such as tolylene diamine, stubble diamine, and diphenylmethane diamine, ethyl diamine, and propylene diamine. Diamine, hexanediamine, 2,2-dimethyl-1,3-propanediamine, 2-methyl-1,5-pentanediamine, trimethylhexanediamine, 2-butane Aliphatic diamines such as yl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1 -Amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, diisopropylidenecyclohexyl-4,4'-diamine, 1,4 -Alicyclic diamines such as diaminocyclohexane and 1,3-bisaminomethylcyclohexane.

Although the urethane resin may use a solvent as a medium, it is preferred to use water as a medium. There are forced emulsification type in which urethane resin is dispersed or dissolved in water, emulsifier is used, self-emulsification type or water-soluble type introduced into hydrophilic urethane resin. Especially the self-emulsifying type in which ion groups are introduced into the structure of the urethane resin for ion polymerization, the storage stability of the liquid or the resistance of the coating layer obtained It is preferable because it has excellent water-based and transparency. In addition, as the introduced ionic group, various kinds such as carboxyl group, sulfonic acid, phosphoric acid, phosphonic acid, and fourth-order ammonium salt can be mentioned, but a carboxyl group is preferred. As a method for introducing a carboxyl group into the urethane resin, various methods can be used in each stage of the polymerization reaction. For example, there is a method of using a resin having a carboxyl group as a copolymerization component during synthesis of a prepolymer, or a method of using a component having a carboxyl group as one of components such as polyol, polyisocyanate, and chain extender. In particular, a method of using a carboxyl group-containing diol and introducing a desired amount of carboxyl group by the addition amount of this component is preferred. For example, for the diol used in the polymerization of urethane resin, dimethylolpropionic acid, dimethylolbutanoic acid, bis-(2-hydroxyethyl)propionic acid, bis-(2-hydroxyl) can be copolymerized Ethyl) butyric acid and so on. In addition, the carboxyl group is preferably in the form of a neutralized salt such as ammonia, amine, alkali metals, inorganic bases and the like. Particularly preferred are ammonia, trimethylamine, and triethylamine. In this polyurethane resin, in the drying step after coating, the carboxyl group excluding the neutralizing agent can be used as the crosslinking reaction point by other crosslinking agents. Thereby, in addition to being excellent in the stability of the state of the solution before coating, it becomes possible to further improve the durability, solvent resistance, water resistance, block resistance, etc. of the resulting coating layer.

Specific examples of the crosslinking agent include melamine compounds, oxazoline compounds, epoxy compounds, isocyanate-based compounds, carbodiimide-based compounds, and silane coupling compounds. Among these cross-linking agents, from the viewpoint of the high cross-linking density, it is particularly preferable to use a melamine compound. In addition, two or more of these crosslinking agents can be used in combination.

The so-called melamine compound is a compound having a melamine skeleton in the compound, for example, it can be used for hydroxyalkylation of melamine derivatives Biological, hydroxyalkylated melamine derivatives react alcohols to partially or fully etherify compounds, and mixtures of these. As the alcohol used for etherification, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, isobutanol and the like are suitably used. As the melamine compound, either a monomer or a polymer of dimer or more may be used, or a mixture of these may be used. Furthermore, co-condensed urea and the like can be used for a part of melamine. In order to improve the reactivity of the melamine compound, a catalyst can also be used.

The so-called oxazoline compound is a compound having an oxazoline group in the molecule, especially a polymer containing an oxazoline group, which can be added by a monomer containing an addition-polymerizable oxazoline group alone or Polymerization with other monomers. The monomer containing an addition-polymerizable oxazoline group includes 2-ethylene-2-oxazoline, 2-ethylene-4-methyl-2-oxazoline, 2-ethylene-5-methyl-2 -Oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline One or more of these may be used as a mixture. Among these, 2-isopropenyl-2-oxazoline is also easy to obtain industrially, so it is suitable. Other monomers are not limited as long as they are copolymerizable with monomers containing an addition-polymerizable oxazoline group, and examples include alkyl (meth)acrylates (as alkyl groups there are methyl and ethyl , N-propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl, cyclohexyl), etc. (meth)acrylates; acrylic acid, methacrylic acid, Iraq Unsaturated carboxylic acids such as carboxylic acid, maleic acid, fumaric acid, crotonic acid, styrene sulfonic acid and its salts (sodium salt, potassium salt, ammonium salt, tertiary amine salt, etc.); acrylonitrile, methyl Unsaturated nitriles such as acrylonitrile; (meth)acrylamide, N-alkyl (meth)acrylamide, N,N-dialkyl (meth)acrylamide, (as alkyl, Unsaturated amides such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl, cyclohexyl, etc.); vinyl acetate Vinyl esters such as esters and vinyl propionate; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; α-olefins such as ethylidene and propylidene; chlorinated ethylene, vinylidene chloride, etc. Of halogen-containing α,β-unsaturated monomers; styrene, α-methylstyrene, etc. α,β-unsaturated aromatic monomers, etc., one or more of these can be used body.

The epoxy compound is a compound having an epoxy group in the molecule, and examples thereof include condensation products of epichlorohydrin with ethylene glycol, polyethylene glycol, glycerin, polyglycerin, and bisphenol A, etc., with hydroxyl groups or amine groups. , Polyepoxy compounds, diepoxy compounds, monoepoxy compounds, glycidyl amine compounds, etc. Examples of the polyepoxy compound include sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, neopentyl alcohol polyglycidyl ether, and diglycerin polyglycidyl ether. , Triglycidyl ginseng (2-hydroxyethyl) isocyanate, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, as the diepoxy compound, for example, neopentyl di Alcohol diglycidyl ether, 1,6-hexanediol diglycidyl ether, resorcinol diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether Propyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, examples of monoepoxy compounds include allyl glycidylpropylene Ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, as the glycidyl amine compound, N,N,N',N'-tetraglycidyl-m- Stubble diamine, 1,3-bis(N,N-diepoxypropylamino) cyclohexane, etc.

Still, the cross-linking agent is used in the drying process, or the film making process, It is designed to increase the performance of the coating layer by making it react. In the finished coating layer, it can be presumed that there are unreacted materials, reacted compounds, or a mixture of these crosslinking agents.

In addition, the particles may be used in combination for the purpose of improving the blockability or slipperiness of the coating layer in the formation of the coating layer within a range that does not impair the gist of the present invention.

Furthermore, defoaming agents, coating improvers, tackifiers, organic lubricants, ultraviolet absorbers, antioxidants, and antioxidants may be used in combination in the formation of the coating layer if necessary, without impairing the gist of the present invention. Foams, dyes, pigments, etc.

As a ratio of all non-volatile components in the coating liquid forming the coating layer, the compound containing a long-chain alkyl group is usually 8 to 70% by weight, preferably 10 to 60% by weight, and more preferably 15 to 50 Weight% range. When it is less than 8% by weight, there is a possibility that sufficient release properties may not be obtained, and when it is more than 70% by weight, there are possibilities that antistatic properties or transparency may not be obtained due to few other components .

As the ratio of the total non-volatile components in the coating liquid forming the coating layer, the antistatic agent is usually 10 to 70% by weight, preferably 15 to 60% by weight, and more preferably 20 to 50% by weight. . If it is less than 10% by weight, there is a possibility that sufficient antistatic performance will not be obtained. If it is more than 70% by weight, there will be no possibility of releasing or transparency due to the small amount of other components .

As a ratio of all non-volatile components in the coating liquid forming the coating layer, acrylic resin or polyvinyl alcohol is usually 3 to 70 weight %, preferably 5 to 60% by weight, more preferably 10 to 50% by weight. When it deviates from the above range, there may be a case where sufficient transparency is not obtained, or an antistatic property or film release property is not obtained.

The crosslinking agent is usually 6 to 70% by weight, preferably 10 to 70% by weight, and more preferably 20 to 70% by weight as a ratio of all nonvolatile components in the coating liquid forming the coating layer. . When it is less than 6% by weight, the roughness of the surface of the photosensitive resin layer after protection peeling is increased, and there is a possibility that sufficient adhesion to the copper foil of the substrate cannot be sufficiently obtained. When it is more than 70% by weight, There is a possibility that sufficient release properties cannot be obtained.

When the coating layer is provided by on-line coating, it is preferable to apply one of the above-mentioned series of compounds as an aqueous solution or dispersion, and apply the coating solution with the solid concentration adjusted to a target of about 0.1 to 50% by weight. The essentials on the polyester film are used to make the protective film. In addition, the coating liquid may contain a small amount of organic solvent for the purpose of improving the dispersibility of water, improving the film-forming property, etc., without impairing the gist of the present invention. Only one type of organic solvent may be used, or two or more types may be used appropriately.

The thickness of the coating layer (after drying) is usually 0.005 to 1 μm, preferably 0.01 to 0.2 μm, more preferably 0.02 to 0.1 μm, and particularly preferably 0.02 to 0.04 μm. When the thickness of the coating exceeds 1 μm, the appearance or transparency may be deteriorated. When the thickness of the coating is less than 0.005 μm, sufficient release properties or antistatic properties may not be obtained.

As a method of forming the coating layer, for example, gravure coating, reverse roll coating, die coating, air knife coating, blade coating, rod coating, rod coating, curtain coating can be used , Knife coating, transfer roller coating Conventionally known coating methods such as cloth, extrusion coating, impregnating coating, kiss coating, spray coating, calendar coating, and extrusion coating.

The drying and curing conditions when forming the coating layer are not particularly limited. For example, when the coating layer is provided by off-line coating, it is usually 80 to 200°C for 3 to 40 seconds, preferably 100 to 180°C. It is better to conduct heat treatment for the next 3 to 40 seconds.

On the other hand, when the coating layer is provided by in-line coating, it is generally preferable to perform heat treatment with a target of 70 to 270° C. for 3 to 200 seconds.

In addition, regardless of offline coating or online coating, if necessary, active energy rays such as heat treatment and ultraviolet irradiation may be used in combination. The polyester film constituting the laminated polyester film of the present invention may be previously subjected to surface treatments such as corona treatment and plasma treatment.

The maximum protrusion height (Rt) of the surface of the coating layer of the protective film of the present invention must be 0.1 to 1.0 μm. When the Rt is less than 0.1 μm, the protective film is wound into a roll, or when the protective film and the base film coated with the photosensitive resin layer are laminated into a roll, wrinkles are generated, or it is difficult to eliminate At the same time, when the film is wound at high speed, the film is accompanied by air, which causes the end face of the roller to shift. On the other hand, when Rt exceeds 1.0 μm, trapped air is generated between the protective film and the photoresist, and the photoresist tends to harden due to the reaction between oxygen and the photoresist. The surface shape is transferred to increase the roughness of the surface of the photosensitive resin layer after peeling, which results in poor adhesion to the copper foil of the substrate and leads to circuit defects.

For the peeling force of the adhesive tape of the protective film of the present invention It is usually 2000 mN/cm or less, preferably 1700 mN/cm or less, and more preferably 1200 mN/cm or less. When the peeling force is higher than 2000 mN/cm, there may be cases where the photoresist layer in contact with the coating layer cannot be smoothly peeled off.

The surface resistance value of the protective film of the present invention is usually 5×10 ¹² Ω or less, preferably 5×10 ¹¹ Ω or less, more preferably 1×10 ¹¹ Ω or less, and particularly preferably 1×10 ¹⁰ Ω or less.

The film haze value of the protective film of the present invention is usually 1 to 7%, preferably 2 to 7%, and more preferably 3 to 7%. In the case where the film fog value is less than 1%, there may be a case where a defective part that does not need to be detected is detected, causing a decrease in the yield. On the other hand, if it exceeds 7%, the transparency is lowered, and resistance may occur during the inspection step accompanying the optical evaluation.

In addition, the polyester film constituting the protective film may be previously subjected to surface treatments such as corona treatment and plasma treatment.

Next, the photosensitive resin layer constituting the laminate of the present invention will be described below.

As the photosensitive resin layer constituting the photosensitive resin laminate of the present invention, a conventional photoresist layer can be used. Generally, as a photoresist layer for DFR, a negative type photoresist is widely used, and it is mainly composed of a thermoplastic resin and a photosensitive material dissolved or swelled in a developing solution. In the DFR step, a circuit (image) is formed by developing only the exposed part, and the unexposed part is dissolved and removed by a developing solution as a feature.

Examples of the thermoplastic resin include phenol resin, cresol resin, polyvinyl phenol resin, polyacrylic resin, and polyethylcarbamate. Ester resin, polyester resin, polyamide resin, epoxy resin, etc. In addition, it may contain styrene-butadiene block copolymer resin, styrene-isoprene copolymer resin, styrene-butadiene block copolymer resin, acrylonitrile-butadiene block copolymer resin , Styrene-isoprene block copolymer resin, methyl methacrylate-butadiene block copolymer resin, polybutadiene, polyisoprene, natural rubber, etc. These thermoplastic resins can be used alone or as a mixture of two or more.

In addition, as the photosensitive material, a compound having a photopolymerizable group or a photoreactive group is used. As a specific example, an ethylenically unsaturated monomer, an ethylenically unsaturated prepolymer, etc. are illustrated.

Specific examples of the ethylenically unsaturated monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, and 1,3. -Aromatic vinyl monomers such as dimethylstyrene, chlorostyrene, vinylnaphthalene, vinylanthracene, divinylbenzene, trivinylbenzene, etc.; ethylenically unsaturated nitrile monomers such as acrylonitrile, methacrylonitrile; acrylic acid Methyl ester, ethyl acrylate, propyl acrylate, n-pentyl acrylate, isoamyl acrylate, hexyl acrylate, ethylhexyl acrylate, octyl acrylate, glycidyl acrylate, methyl methacrylate, methyl Ethyl acrylate, propyl methacrylate, n-pentyl methacrylate, isoamyl methacrylate, hexyl methacrylate, ethyl hexyl methacrylate, octyl methacrylate, hydroxyethyl acrylate, Hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl methacrylate, ethylene glycol diacrylate, trimethylolpropane triacrylate, 1,4-butanediol Diacrylate, 1,4-butanediol dimethacrylate, propylene glycol diacrylate Ester, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol diacrylate, 1,9-nonanediol dimethacrylate, Methoxyethylene glycol acrylate, methoxypropylene glycol methacrylate, methoxyethylene glycol methacrylate, methoxypropylene glycol acrylate, diethyl maleate, dimethyl itaconate, Ethylene unsaturated carboxylate monomers such as dioctyl fumarate; ethylenically unsaturated epoxy propyl ethers such as allyl epoxypropyl ether; ethylenically unsaturated monomers such as acrylic acid and methacrylic acid Carboxylic acids; ethylenically unsaturated polycarboxylic acids such as maleic acid, fumaric acid, citraconic acid, and itaconic acid; ethylenically unsaturated polycarboxylic acids such as monoethyl maleate and monomethyl acid Some of the esterified compounds; Ethyl acrylate phosphate, Trimethylene acrylate phosphate, Ethyl acrylate phosphate, Tetramethylene acrylate phosphate, Ethyl acrylate phosphate, Ditrimethylene phosphate acrylate, Ditetramethylene phosphate acrylate Ester, diethylene glycol acrylate phosphate, triethylene glycol acrylate phosphate, polyethylene glycol acrylate phosphate, bis diethylene glycol acrylate phosphate, bis triethylene glycol acrylate phosphate, bis polyethylene glycol phosphate Acrylic acid esters, methacrylic acid esters, etc. corresponding to ethylenically unsaturated monomers containing phosphate ester groups, etc.

On the other hand, as the ethylenically unsaturated prepolymer, for polyester, polyurethane, polyether, epoxy resin, acrylic resin, etc., ethylene having a reactive group such as a carboxyl group, a hydroxyl group, an isocyanate group, etc. is used As for the unsaturated compounds, those introduced with ethylenically unsaturated groups are used. Examples of such ethylenically unsaturated prepolymers include unsaturated polyesters, unsaturated polyurethanes, unsaturated polyethers, unsaturated epoxy resins, and unsaturated acrylic resins.

The content of the photosensitive material is usually 5 to 100 parts by mass relative to 100 parts by mass of the thermoplastic resin. In addition, the photosensitive resin layer may contain a photopolymerization initiator, a plasticizer, a storage stabilizer, a surfactant, a coloring agent, etc. within a range that does not impair the gist of the present invention.

Examples of the photopolymerization initiator include α-diketones such as diethyl acetyl and benzyl; acetoin and benzoin, such as benzoin and pivaloin nindione (Pivaloin); benzoin methyl ether and benzoin ethyl ether Benzoin ethers such as benzoin isopropyl ether; polynuclear quinones such as anthraquinone and 1,4-naphthoquinone; benzophenone such as methyl-o-benzoyl benzoate; 2,2- Dimethoxy-2-phenylacetophenone and other phenyl ketones. The content of the photopolymerization initiator is usually 0.1 to 10 parts by mass relative to 100 parts by mass of the total amount of the thermoplastic resin and the photosensitive material.

In order to ensure the flexibility of the photosensitive resin layer obtained, a plasticizer may be used together. The plasticizer is not particularly limited as long as it is uniformly compatible with other components forming the photosensitive resin layer and exhibits a plasticizing effect. As specific examples of the plasticizer, for example, glycerin, polyethylene glycol, besylate, tosylate, N-ethyltoluenesulfonamide, N-methyltoluenesulfonamide, p-hydroxybenzyl Hydrocarbon oils such as acid esters, various olefin-based oligomers, ethylene-based oligomers, diene-based oligomers, naphthenic oil, paraffin oil, etc.

Examples of storage stabilizers include dihydroquinone, pyrogallol, p-methoxyphenol, t-butylcatechol, 2,6-di-t-butyl-p-cresol, and 2,2 -Phenols such as di-t-butyl-p-cresol; quinones such as benzoquinone, p-toluone, p-quinone (Xyloquinone); amines such as phenyl-α-naphthylamine, etc. .

As surfactant, anionic surfactant can be used Agents, nonionic surfactants, cationic surfactants, homosexual surfactants. Among these, from the viewpoint of compatibility and water development effect, nonionic surfactants and anionic surfactants are preferred, and anionic surfactants are particularly preferred.

Regarding the method of manufacturing the photosensitive resin layer, for example, after dissolving each component constituting the aforementioned photosensitive resin composition in water or an organic solvent, and thoroughly mixing into a homogeneous solution, a conventionally known coating method can be applied on the surface of the base film For example, the reverse coating method, gravure coating method, rod coating method, bar coating method, die coating method, etc. can be used for coating, drying, and then forming the thickness on the base film (After drying) It is a method of 1~1000μm photosensitive resin layer.

In addition, a solvent in which the material for forming the photosensitive resin layer is distilled in advance may be heated and pressed on the base film by a nip roll or the like, and a photosensitive resin layer may be formed on the base film.

Furthermore, a method in which the components constituting the photosensitive resin composition are sufficiently mixed with a kneader, a Banbury mixer, or the like can be stamped and formed on the base film to form a photosensitive resin layer, and other methods such as casting and extrusion Methods for forming a photosensitive resin layer such as molding are conventionally known methods.

Examples

Hereinafter, although the present invention will be further described in detail by examples, the present invention is not limited to the following examples as long as the gist is not exceeded. The measurement method used in the present invention is as follows.

(1) Determination of inherent viscosity (dI/g) of polyester:

Remove 1 g of polyester that is incompatible with other polymer components and pigments on a polyester scale, add 100 ml of a mixed solvent of phenol/tetrachloroethane = 50/50 (weight ratio) to dissolve, and measure at 30°C.

(2) Measurement of average particle size (d50: μm):

A centrifugal sedimentation type particle size distribution measuring device (Model SA-CP3 manufactured by Shimadzu Corporation) was used, and the measured value of 50% of the total (weight basis) of the equivalent spherical distribution was used as the average particle size.

(3) Determination of the film haze value of the protective film:

Based on the protective film JIS-K-7136, the film haze value was measured with a haze value meter "HM-150" manufactured by Murakami Color Technology Research Institute Co., Ltd.

(4) Maximum protrusion height (Rt) of protective film:

The surface roughness tester (SE-3F) manufactured by Kosaka Research Institute Co., Ltd. was used as follows.

That is, take the part with a reference length of 2.5 mm from the film profile curve in the direction of its centerline, and when the average line is held by the 2 straight lines parallel to the maximum and minimum values, the interval between these 2 straight lines is in the profile curve The direction of the vertical magnification is measured, and the value is expressed in micrometer (μm) units as the maximum protrusion height (Rt) of the selected part. The maximum protrusion height is obtained from the surface of the sample film by 10 cross-section curves, and selected from these cross-section curves The average value of the maximum height of the part.

(5) Peeling force evaluation of release film:

The adhesive tape ("No. 31B" manufactured by Nitto Denko Corporation) on the surface of the sample film was pressed back and forth once on a 2kg rubber roller, and the peeling force after 1 hour of standing at room temperature was measured. The peeling force is 180° peeling at a drawing speed of 300 mm/min using Shimadzu Corporation's "Ezgraph".

(6) Evaluation of the surface resistance of the protective film:

The surface resistance value was measured using a high-resistance measuring device made by Japan Hewlett Packard Co., Ltd.: HP4339B and measuring electrode: HP16008B, and the sample was humidified in a measuring environment at 23° C. and 50% RH for 30 minutes.

(7)Removability of protective film (practical characteristics substitute evaluation):

The coating liquid consisting of the following photosensitive resin composition was applied to a polyester film (made by Mitsubishi Resin, trade name Diafoil: R310 type, 16 μm thick) as a base film, and 100° C. in a hot air circulation furnace, After heat treatment for 10 minutes, a photosensitive resin layer with a thickness (after drying) of 1.5 μm was formed. Next, each protective film obtained in Examples and Comparative Examples was laminated so as to contact the coating layer of the protective film on the surface of the photosensitive resin layer to obtain a roll-shaped photosensitive film with a film width of 1000 mm and a winding length of 2000 m. Resin laminate.

(Photosensitive resin layer composition)

Photosensitive resin methyl methacrylate/methacrylic acid/2-ethylhexyl acrylic acid) 45 parts

6 parts of photopolymerization initiator (Irgacure907: manufactured by Ciba Specialty Chemicals)

Hardener (hexamethoxymethyl melamine) 5 parts

5 parts of coloring agent (methyl violet)

Solvent (methyl ethyl ketone) 70 parts

Solvent (propylene glycol monomethyl ether) 25 parts

，以拉伸試驗機從感光性樹脂層合體剝離保護膜，觀察脫膜性或感光性樹脂層表面之表面狀態，使用下述判定基準進行判定。 Using the obtained photosensitive resin laminate, cut into 15mm in advance

Then, the protective film was peeled off from the photosensitive resin laminate with a tensile tester, the release property or the surface state of the surface of the photosensitive resin layer was observed, and the judgment was performed using the following criteria.

(Judgment criteria)

A: When the protective film is peeled off, it does not cause scratches on the surface of the photosensitive resin layer (a level with no problem in practical use)

B: When the protective film is peeled off, it is peeled off carefully, but it does not scratch the photosensitive resin layer (practically, it may be a problematic level)

C: Peeling is not smooth, causing scratches on the surface of the photosensitive resin layer (a practically problematic level)

(8) Adhesion to photosensitive resin copper foil (substitute evaluation of practical characteristics):

From the photosensitive resin laminate, the protective film was peeled off, and the exposed surface of the photosensitive resin layer and a copper foil with a thickness of 70 μm were laminated. The processing conditions at this time are judged by the following judgment criteria.

(Judgment criteria)

A: When the photosensitive resin layer is laminated on the copper foil, the adhesiveness is excellent, and the photosensitive resin layer does not peel off easily (a level that has no problem in practical use)

B: When laminating the photosensitive resin layer on the copper foil, the adhesion deteriorates and the photosensitive resin layer is easily peeled off (a level that is practically problematic)

(9) Evaluation of the antistatic property of the protective film (substitute evaluation of the practical characteristics of the gray test):

Under the measurement conditions of 23°C and 50% RH, on a cotton cloth stipulated in JIS080 (additional white cloth for dyeing fastness test), use two hands to hold a protective film sample of 200mm×30mm, rub the coating surface of the friction film 20 times back and forth, Charge the protective film. Next, the tobacco ash was brought close to the film coating surface, and the distance (in mm) at which the particles of the ash adhered to the surface of the protective film was measured, and the determination was made based on the following determination criteria.

(Judgment criteria)

A: Distance less than 0mm and less than 10mm (good antistatic property)

B: Distance less than 10mm and less than 20mm (antistatic property: ordinary)

C: The distance exceeds 20mm (poor antistatic property)

(10) Winding characteristics of photosensitive resin laminate (substitute evaluation of practical characteristics):

With respect to each photosensitive resin laminate used in the evaluation of the aforementioned (7), the winding characteristics were determined by the following determination criteria.

(Judgment criteria)

A: The winding of the photosensitive resin layer is tight or the winding is displaced, and there is almost no wrinkle of the roller

(Practically no problem level)

B: Only a part of the photosensitive resin layer is tightly wound or the roller is wrinkled (the level of the case where it is practically a problem)

C: There is tight winding of the photosensitive resin layer or wrinkle of the roller (practically problematic level)

(11) Overall evaluation (substitute evaluation of practical characteristics):

Using the photosensitive resin laminates produced in Examples and Comparative Examples, the evaluation items for the release properties of the protective film, the adhesion to the copper foil of the photosensitive resin, and the winding characteristics of the photosensitive resin laminate, The overall evaluation is conducted by the following judgment criteria.

"Judgment Criteria"

A: The release property of the protective film, the adhesion to the copper foil of the photosensitive resin, and the winding properties of the photosensitive resin laminate are all A (there is no problematic level in practice)

B: At least one of the release properties of the protective film, the adhesiveness to the copper foil of the photosensitive resin, and the winding properties of the photosensitive resin laminate is B (a level that is a problem in practice)

C: At least one of the release property of the protective film, the adhesiveness to the copper foil of the photosensitive resin, and the winding property of the photosensitive resin laminate is C (a practically problematic level)

The polyesters used in the examples and comparative examples were prepared as follows.

<Manufacturing method of polyester (A)>

Using 100 parts by weight of dimethyl terephthalate and 60 parts by weight of ethylene glycol as starting materials, 0.09 parts by weight of magnesium acetate and tetrahydrate was taken into the reactor as a catalyst, and the reaction start temperature was set at 150°C. While distilling off methanol, the reaction temperature was slowly increased, and after 3 hours, it became 230°C. After 4 hours, the transesterification reaction was substantially completed. After adding 0.04 part by weight of ethyl acid phosphate to this reaction mixture, 0.04 part by weight of antimony trioxide was added to carry out the condensation polymerization reaction for 4 hours. That is, the temperature is gradually increased from 230°C to 280°C. On the other hand, the pressure gradually decreases from normal pressure, and eventually becomes 0.3 mmHg. After the reaction started, the reaction was stopped at a time equivalent to the limit viscosity of 0.63 by changing the stirring power of the reaction tank, and the polymer was spit out under nitrogen pressure. The ultimate viscosity of the obtained polyester (A) was 0.63.

<Manufacturing method of polyester (B)>

In the manufacturing method of polyester (A), add 0.04 weight of ethyl acid phosphate After parts, add 0.2 parts by weight of silica particles with an average particle diameter of 2 μm, and 0.04 parts by weight of antimony trioxide. Use the method of manufacturing polyester (A) except that the polycondensation reaction is stopped at a time equivalent to the limit viscosity of 0.65. The polyester (B) was obtained by the same method. The polyester (B) obtained had an ultimate viscosity of 0.65.

<Manufacturing method of polyester (C)>

In the production method of polyester (B), in addition to replacing 0.2 parts by weight of silica particles with an average particle diameter of 2 μm, and adding 0.5 parts by weight of silica particles with an average particle diameter of 0.9 μm, the others are used with polyester (B ) Is produced in the same way as polyester (C). The polyester (C) obtained had an ultimate viscosity of 0.65.

<Manufacturing method of polyester (D)>

In the manufacturing method of polyester (B), in addition to replacing 0.2 parts by weight of silica particles with an average particle diameter of 2 μm, and adding 0.7 parts by weight of silica particles with an average particle diameter of 2 μm, the others are used as polyester (B) The polyester (D) was obtained by the same method as the manufacturing method. The polyester (D) obtained had a limiting viscosity of 0.65.

<Manufacturing method of polyester (E)>

In the manufacturing method of polyester (B), in addition to replacing 0.2 parts by weight of silica particles with an average particle diameter of 2 μm, and adding 0.5 parts by weight of silica particles with an average particle diameter of 0.2 μm, the others are used with polyester (B ) Is produced in the same way as polyester (E). The resulting polyester (E) ultimate viscosity is 0.65.

<Manufacturing method of polyester (F)>

In the manufacturing method of polyester (B), in addition to replacing 0.2 parts by weight of silica particles with an average particle diameter of 2 μm, and 1.5 parts by weight of silica particles with an average particle diameter of 3.5 μm, other materials are used as polyester (B). ) Is produced in the same way as the polyester (F). The resulting polyester (F) has an ultimate viscosity of 0.65.

Examples of compounds constituting the coating layer are as follows.

(Example of compound) ‧Release agent (long-chain alkyl compound): (IA)

In a 4-neck flask, 200 parts of xylene and 600 parts of octadecyl isocyanate were added and heated with stirring. From the time point at which xylene was refluxed, 100 parts of polyvinyl alcohol with an average degree of polymerization of 500 and a degree of saponification of 88 mole% were added little by little at intervals of about 2 hours every 10 minutes. After the addition of polyvinyl alcohol was completed, reflux was further performed for 2 hours to complete the reaction. After cooling the reaction mixture to about 80°C several times and adding it to methanol, the reaction product precipitated as a white precipitate. The precipitate was filtered out, 140 parts of xylene was added, and after heating to completely dissolve, methanol was added to make After the precipitation operation, the precipitate was washed with methanol, dried and pulverized.

‧Antistatic agent: IIA

Combine the structural unit of the following formula 3-1 with the structural unit of the following formula 3-2 Polymer compound copolymerized at a weight ratio of 95/5, with a number average molecular weight of 30,000

‧Antistatic agent: IIB

Copolymerized structural unit of formula 3-1, high molecular compound with number average molecular weight of 30,000

‧Antistatic agent: IIC

The counter ion is 2-(trimethylamino) ethyl methacrylate of methyl sulfonate/methacrylic acetate/butyl methacrylate/monoacrylate containing polyethylene glycol at a weight ratio of 75/12/15/30 copolymer. The number average molecular weight is 40,000.

‧Antistatic agent: IID

It is composed of the structural unit of the following formula 4, and the antistatic agent with a number average molecular weight of 50000

‧Acrylic resin: Aqueous dispersion of acrylic resin polymerized with the following composition (IIIA)

Ethyl acrylate/n-butyl acrylate/methyl methacrylate/N-methylol acrylamide/acrylic acid=65/21/10/2/2 (wt%) emulsified polymer (emulsifier: anionic Surfactant). The hydroxyl value is 11mgKOH/g.

‧Acrylic resin: Aqueous dispersion of acrylic resin polymerized with the following composition (IIIB)

Ethyl acrylate/methacrylate/2-hydroxyethyl methacrylate/N-methylol acrylamide/acrylic acid=65/28/3/2/2 (wt%) emulsified polymer (emulsion Agent: anionic surfactant). The hydroxyl value is 24mgKOH/g.

‧Polyvinyl alcohol: (IIIC)

Polyvinyl alcohol with a saponification degree of 88 mole% and a polymerization degree of 500

‧ Hexamethoxyhydroxymethyl melamine: (IV) Example 1:

As the raw material of the outermost layer (surface layer), the mixed raw materials of polyester (A) and (B) mixed in the proportions of 5 wt% and 95 wt%, respectively, and only the polyester (A) as the raw material of the intermediate layer are supplied to Two extruders were melted at 285°C, and then on a cooling roll set at 40°C, two types of three layers (surface layer/intermediate layer/surface layer=2:8:2 discharge rate) were used for total Extrusion was allowed to cool and solidify to obtain an unstretched sheet. Next, using the difference in roller peripheral speeds, the film was stretched 3.4 times in the longitudinal direction at a film temperature of 85°C. On one side of this longitudinally stretched film, the coating liquid 1 shown in Table 1 below was applied to a tenter. , Stretched 4.1 times at 110°C in the horizontal direction, and heat-treated at 230°C for 10 seconds, then relaxed 2% in the horizontal direction to obtain a protective film with a thickness of 12 μm having a coating thickness of 0.03 μm (after drying) .

Examples 2-18:

In Example 1, except that the composition of the coating agent was changed to the composition of the coating agent shown in Table 1, it was manufactured in the same manner as in Example 1 to obtain a protective film.

Example 19:

In Example 1, except that the blending of the raw materials of the surface layer of the polyester film constituting the protective film was changed to 5 wt% and 95 wt% of polyester (A) and (C), respectively, the other 1 was produced in the same way to obtain a protective film.

Example 20:

In Example 1, except that the raw material blend of the surface layer of the polyester film constituting the protective film was changed to polyester esters (A) and (D) at a ratio of 5% by weight and 95% by weight, respectively, the other Example 1 was produced in the same manner to obtain a protective film.

Example 21:

In Example 1, except that the composition of the coating agent was changed to the composition of the coating agent shown in Table 1, it was manufactured in the same manner as in Example 1 to obtain a protective film.

Comparative example 1:

In Example 1, except that the coating layer was not provided, it was manufactured in the same manner as in Example 1 to obtain a polyester film. The evaluation of the completed laminated polyester film was as shown in Table 2 and it was degraded in release properties or antistatic properties.

Comparative examples 2~3:

In Example 1, except that the composition of the coating agent was changed to the composition of the coating agent shown in Table 1, the others were produced in the same manner as in Example 1 to obtain Protective film.

Comparative Example 4:

In Example 1, except that the raw material blend of the surface layer of the polyester film constituting the protective film was changed to polyester (A) and (E) at a ratio of 5% by weight and 95% by weight, respectively, the same as Example 1 The same process is carried out to obtain a protective film.

Comparative Example 5:

In Example 1, except that the raw material blend of the surface layer of the polyester film constituting the protective film was changed to polyester (A) and (F) at a ratio of 5% by weight and 95% by weight, respectively, the same as Example 1 The same process is carried out to obtain a protective film.

Comparative Example 6:

In Example 1, except that the composition of the coating agent was changed to the composition of the coating agent shown in Table 1, it was manufactured in the same manner as in Example 1 to obtain a protective film.

The characteristics of the protective films obtained in the above examples and comparative examples are shown in Tables 1 to 2 below.

Industrial availability

The protective film of the present invention can be suitably used as a protective film for dry film photoresist.

Claims (6)

A protective film for dry film photoresist, characterized in that it has a coating layer formed by a coating liquid on one side of a polyester film, the coating liquid containing a compound containing a long-chain alkyl group, a cross-linking agent and Electrostatic agent, with acrylic resin or polyvinyl alcohol, the maximum protrusion height (Rt) of the surface of the coating layer is 0.1 to 1.0 μm, wherein, as the ratio of all non-volatile components in the coating liquid, it contains long-chain alkanes The base compound is 15 to 70% by weight, the crosslinking agent is 6 to 70% by weight, the antistatic agent is 10 to 70% by weight, and the acrylic resin or polyvinyl alcohol is 3 to 70% by weight. For example, the protective film for dry film photoresist of claim 1, wherein the haze value of the film is 2 to 7%. The protective film for dry film photoresist according to claim 1, wherein the compound containing a long-chain alkyl group is a polymer compound having a long-chain alkyl group in the side chain. The protective film for dry film photoresist according to any one of claims 1 to 3, wherein the antistatic agent is a polymer having a constituent element represented by the following formula (1) as a repeating unit;

In formula (1), R ² is -O- or -NH-, R ³ is an alkylene group, or other structure that can form the structure of formula (1); R ¹ , R ⁴ , R ⁵ , and R ⁶ are respectively It is selected from hydrogen atom, alkyl group and phenyl group, and these alkyl groups and phenyl groups can be substituted by the groups shown below. The substitutable groups are hydroxyl group, amide group, ester group, alkoxy group and phenoxy group , Naphthoxy, thioalkoxy, thiophenoxy, cycloalkyl, trialkylammonium alkyl, cyano and halogen; X ^- is selected from halogen ion, sulfonate, phosphate, nitrate, alkyl Sulfonate and carboxylate. The protective film for dry film photoresist according to any one of claims 1 to 3, wherein the antistatic agent is a polymer having a constituent element represented by the following formula (2) as a repeating unit;

In formula (2), R ¹ and R ² are each independently selected from a hydrogen atom, an alkyl group, and a phenyl group, and these alkyl groups and phenyl groups may be substituted with the groups shown below, and the substituted groups are hydroxyl groups, Acylamino, ester, alkoxy, phenoxy, naphthoxy, thioalkoxy, thiophenoxy, cycloalkyl, trialkylammonium alkyl, cyano and halogen; and, R ¹ and R ² can also be chemically bonded, and the bonding part is selected from -(CH ₂ ) _m -(m=integer of 2~5), -CH(CH ₃ )CH(CH ₃ )-, -CH=CH- CH=CH-, -CH=CH-CH=N-, -CH=CH-N=C-, -CH ₂ OCH ₂ -, and -(CH ₂ ) ₂ O(CH ₂ ) ₂ -; X ^- is It is selected from halogen ion, sulfonate, phosphate, nitrate, alkylsulfonate and carboxylate. A photosensitive resin laminate characterized by having a base film The structure of the protective film as described in any one of claims 1 to 5 is laminated on the surface of the formed photosensitive resin layer.

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