JP2011095731A - Photosensitive composition, photosensitive laminate, method for forming permanent pattern, and printed board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a photosensitive composition having high thermal cycle test resistance, high storage stability, and a smooth-shape inner surface when a via is formed; a photosensitive laminate using the photosensitive composition; a method for forming a permanent pattern; and a printed board. <P>SOLUTION: The photosensitive composition contains at least a binder, a polymerizable compound, and a filler. The binder has an acid group and ethylenically unsaturated bond in a side chain, and has any of a bisphenol A type skeleton and a bisphenol F type skeleton. The filler is spherical silica surface-treated with a silane coupling agent. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a photosensitive composition, a photosensitive laminate, a method for forming a permanent pattern, and a printed board suitable as a solder resist material.

  Conventionally, when forming a permanent pattern such as a solder resist, a method of forming a photosensitive layer by forming a coating film by drying a liquid photosensitive composition using a screen printing method or a spray printing method, on a support A method of forming a photosensitive layer by applying a photosensitive composition to a photosensitive film by drying and forming a photosensitive film using a vacuum laminator or a roll laminator has been used. As a method of forming a permanent pattern such as a solder resist, for example, a photosensitive layer is formed by the above-described method on a substrate such as a copper-clad laminate on which a permanent pattern is formed, and the photosensitive layer in the laminate is formed. A method of forming a permanent pattern by performing exposure, developing the photosensitive layer after the exposure to form a pattern, and then performing a curing process or the like is known.

  The formation of the permanent pattern is also applied to a package substrate interposed between a semiconductor chip and a printed board. In recent years, the package substrate has been required to have higher density, and it is considered that the wiring pitch is narrowed and the solder resist layer is made thinner. For this reason, repeated cold shock resistance (thermal cycle test resistance, TCT resistance) is strongly demanded. In addition, a reduction in the diameter of the via is also required, and the smoothness of the tapered shape is required from the viewpoint of mountability. Furthermore, the photosensitive composition needs to be excellent in storage stability from the viewpoint of convenience.

So far, it contains an acid-modified vinyl group-containing epoxy resin, a photopolymerization initiator, a diluent, a curing agent, an acrylic resin having a specific molecular weight, and a photosensitivity containing silica that has been surface-treated. Resin compositions have been proposed (see, for example, Patent Document 1). According to this proposal, it is said that a high-performance cured film excellent in exposure latitude, development latitude and the like can be obtained. Although details of the shape of the silica used in this proposal are not described, usually, in solder resist applications, silica obtained by crushing quartz is used, and the proposed silica is not spherical. it is conceivable that.
In addition, the photosensitive composition includes a binder, a polymerizable compound, a photopolymerization initiator, a thermal crosslinking agent, and an inorganic pigment, the photopolymerization initiator includes an oxime derivative, and the inorganic pigment is surface-treated with a silane coupling agent. A composition has been proposed (see, for example, Patent Document 2). According to this proposal, sensitivity, developability, and adhesion are good, and a high-definition permanent pattern can be efficiently formed.

  However, none of the techniques of the above-mentioned prior art documents have sufficient performance for various characteristics such as thermal cycle test resistance, storage stability, and smooth inner wall shape when vias are formed. However, the present situation is that further improvement and development are desired.

JP 2007-256943 A JP 2008-102486 A

  This invention is made | formed in view of this present condition, and makes it a subject to solve the said various problems in the past and to achieve the following objectives. That is, the present invention relates to a photosensitive composition having excellent thermal cycle test resistance and storage stability, and having a smooth inner wall shape when a via is formed, and a photosensitive laminate using the photosensitive composition. An object is to provide a body, a method for forming a permanent pattern, and a printed circuit board.

  As a result of intensive studies by the present inventors in order to solve the above problems, the binder has an acidic group and an ethylenically unsaturated bond in the side chain, and the bisphenol A skeleton and the bisphenol F skeleton It has been found that the above problem can be effectively solved by using any of the above and the filler is spherical silica surface-treated with a silane coupling agent.

The present invention is based on the above findings by the present inventors, and means for solving the above problems are as follows. That is,
<1> includes at least a binder, a polymerizable compound, and a filler,
The binder is a polymer compound having an acidic group and an ethylenically unsaturated bond in a side chain, and having any of a bisphenol A skeleton and a bisphenol F skeleton,
The photosensitive composition is characterized in that the filler is spherical silica surface-treated with a silane coupling agent.
<2> Said <1 which surface-treats a silica with the silane coupling agent which has at least 1 sort (s) of functional group selected from an alkoxy silyl group, a chloro silyl group, and an acetoxy silyl group, and a (meth) acryloyl group > Is a photosensitive composition.
<3> The photosensitive composition according to any one of <1> to <2>, further including a thermal crosslinking agent.
<4> In the above <3>, the thermal crosslinking agent is at least one selected from an epoxy resin, an oxetane resin, a bismaleimide resin, a cyanate resin, a benzocyclobutene resin, a bisallylnadiimide resin, and a benzoxazine resin. It is the photosensitive composition of description.
<5> The photosensitive composition according to any one of <1> to <4>, further including an elastomer.
<6> The photosensitive composition according to <5>, wherein the elastomer is a polyester elastomer.
<7> A photosensitive laminate comprising a photosensitive layer containing the photosensitive composition according to any one of <1> to <6> on a substrate.
<8> A method for forming a permanent pattern, comprising at least exposing a photosensitive layer formed of the photosensitive composition according to any one of <1> to <6>.
<9> A printed circuit board wherein a permanent pattern is formed by the method for forming a permanent pattern according to <8>.

  According to the present invention, a photosensitive composition which can solve various problems in the past, has excellent thermal cycle test resistance and storage stability, and has a smooth inner wall shape when a via is formed, the photosensitive composition The photosensitive laminated body using a thing, a permanent pattern formation method, and a printed circuit board can be provided.

(Photosensitive composition)
The photosensitive composition of the present invention contains at least a binder, a polymerizable compound, and a filler, and contains a thermal crosslinking agent, an elastomer, a photopolymerization initiator, and, if necessary, other components.

<Binder>
The binder is a polymer compound having an acidic group and an ethylenically unsaturated bond in a side chain, and having either a bisphenol A skeleton or a bisphenol F skeleton.
The polymer compound, for example, reacts a polyfunctional epoxy compound having either a bisphenol A skeleton or a bisphenol F skeleton with an unsaturated group-containing monocarboxylic acid, and further adds a polybasic acid anhydride. It can be obtained by a method.

-Multifunctional epoxy compound-
The polyfunctional epoxy compound is not particularly limited as long as it has either a bisphenol A skeleton or a bisphenol F skeleton, and can be appropriately selected according to the purpose.
Examples of the polyfunctional epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, epoxy resin derived from bisphenol A type phenol novolac, epoxy resin derived from bisphenol F type phenol novolac, and the like. It is represented by the following general formulas (A1) to (A3). These may be used individually by 1 type and may use 2 or more types together.

In the general formula (A1), R ¹ represents a hydrogen atom or a glycidyl group, and n1 represents 0 or an integer of 1 or more. A plurality of R ¹ may be the same or different. R ² represents a methyl group in the case of bisphenol A type, and represents a hydrogen atom in the case of bisphenol F type.
There is no restriction | limiting in particular as said n1, Although it can select suitably according to the objective, 0-10 are preferable and 0-3 are especially preferable.

In the general formula (A2), R ³ represents a hydrogen atom or a glycidyl group, and n2 represents 0 or an integer of 1 or more. A plurality of R ³ may be the same or different. R ⁴ represents a methyl group in the case of bisphenol A type, and represents a hydrogen atom in the case of bisphenol F type.
There is no restriction | limiting in particular as said n2, Although it can select suitably according to the objective, 0-10 are preferable and 0-3 are especially preferable.

In the general formula (A3), n3 represents 0 or an integer of 1 or more, R ⁵ represents a methyl group in the case of the bisphenol A type, and represents a hydrogen atom in the case of the bisphenol F type.
There is no restriction | limiting in particular as said n3, Although it can select suitably according to the objective, 0-10 are preferable and 0-3 are especially preferable.

  Among these, the polyfunctional epoxy compound represented by the general formula (A1) is particularly preferable in terms of TCT resistance.

  There is no restriction | limiting in particular as a manufacturing method of the polyfunctional epoxy compound represented by the said general formula (A1)-(A3), It can manufacture by a well-known method.

-Monocarboxylic acid containing unsaturated group-
There is no restriction | limiting in particular as said unsaturated group containing monocarboxylic acid, According to the objective, it can select suitably, For example, a dimer of acrylic acid, acrylic acid, methacrylic acid, (beta) -furfuryl acrylic acid, (beta) -Styryl acrylic acid, cinnamic acid, crotonic acid, α-cyanocinnamic acid, hydroxyl group-containing acrylate, half-ester compound which is a reaction product of saturated or unsaturated dibasic acid anhydride, unsaturated group-containing monoglycidyl ether The half ester compound etc. which are reaction products with a saturated or unsaturated dibasic acid anhydride are mentioned. These half ester compounds are obtained by reacting a hydroxyl group-containing acrylate or unsaturated group-containing monoglycidyl ether with a saturated or unsaturated dibasic acid anhydride in an equimolar ratio. The unsaturated group-containing monocarboxylic acid may be used alone or in combination of two or more.

  Examples of the hydroxyl group-containing acrylate and unsaturated group-containing monoglycidyl ether used in the synthesis of the half ester compound which is an example of the unsaturated group-containing monocarboxylic acid include hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxy Propyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol pentaacrylate, penta Erythritol pentamethacrylate Glycidyl acrylate and glycidyl methacrylate and the like.

  Examples of the saturated or unsaturated dibasic acid anhydride used for the synthesis of the half ester compound include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydro Examples thereof include phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride and the like.

  The ratio of both in the reaction of the polyfunctional epoxy compound and the unsaturated group-containing monocarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose, but the epoxy group of the polyfunctional epoxy compound The unsaturated group-containing monocarboxylic acid is preferably reacted at a ratio of 0.6 equivalent to 1.10 equivalent with respect to 1 equivalent, and reacted at a ratio of 0.75 equivalent to 1.05 equivalent. Is more preferable, and the reaction is particularly preferably performed at a ratio of 0.9 equivalent to 1.0 equivalent.

  The polyfunctional epoxy compound and the unsaturated group-containing monocarboxylic acid can be dissolved and reacted in an organic solvent. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, Glycol ethers such as propylene glycol monoethyl ether, dipropylene glycol diethyl ether and triethylene glycol monoethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate and carbitol acetate, and aliphatic hydrocarbons such as octane and decane And petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha and solvent naphtha.

Furthermore, it is preferable to use a catalyst for promoting the reaction between the polyfunctional epoxy compound and the unsaturated group-containing monocarboxylic acid. Examples of the catalyst include triethylamine, benzylmethylamine, methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, and the like.
It is preferable that the usage-amount of a catalyst is 0.1 mass part-10 mass parts with respect to a total of 100 mass parts of the said polyfunctional epoxy compound and the said unsaturated group containing monocarboxylic acid.

  Moreover, it is preferable to use a polymerization inhibitor for the purpose of preventing polymerization during the reaction. Examples of the polymerization inhibitor include hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol and the like. It is preferable that the usage-amount of the said polymerization inhibitor is 0.01 mass part-1 mass part with respect to a total of 100 mass parts of the said polyfunctional epoxy compound and the said unsaturated group containing monocarboxylic acid.

  Moreover, it is preferable that the reaction temperature at the time of making the said polyfunctional epoxy compound and the said unsaturated group containing monocarboxylic acid react is 60 to 150 degreeC, and it is more preferable that it is 80 to 120 degreeC.

  Furthermore, the unsaturated group-containing monocarboxylic acid may be a polybasic acid anhydride such as trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, biphenyltetracarboxylic anhydride, phenylglycine, if necessary. , Monocarboxylic acid compounds such as hydroxyacetic acid, and phenolic compounds such as p-hydroxyphenethyl alcohol.

  The binder can be obtained by reacting a polybasic acid anhydride with a reaction product of the polyfunctional epoxy compound and the unsaturated group-containing monocarboxylic acid.

-Polybasic acid anhydride-
The polybasic acid anhydride is not particularly limited and may be appropriately selected depending on the intended purpose.For example, succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, Examples thereof include ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride and the like.

  In the reaction between the polyfunctional epoxy compound, the unsaturated product-containing monocarboxylic acid, and the polybasic acid anhydride, the polybasic acid is used with respect to 1 equivalent of the hydroxyl group in the reaction product. By reacting the anhydride with 0.1 equivalent to 1.0 equivalent, the acid value of the obtained binder can be adjusted.

  The acid value of the binder is preferably 30 mgKOH / g to 150 mgKOH / g, and more preferably 50 mgKOH / g to 120 mgKOH / g. When the acid value is less than 30 mgKOH / g, the solubility of the photosensitive resin composition in a dilute alkaline solution tends to be reduced, and when it exceeds 150 mgKOH / g, the electrical properties of the cured film tend to be reduced. .

  The reaction temperature in the reaction between the polyfunctional epoxy compound, the reaction product of the unsaturated group-containing monocarboxylic acid, and the polybasic acid anhydride is preferably 60 ° C to 120 ° C.

  5 mass%-80 mass% are preferable, and, as for content in the said photosensitive composition solid content of the said binder, 30 mass%-60 mass% are more preferable. When the content is 5% by mass or less, the exposure sensitivity is low, and the processing time becomes long, which causes a problem. On the other hand, if it is 80 mass% or more, TCT tolerance will fall large and will become a problem.

<Filler>
The filler is spherical silica surface-treated with a silane coupling agent. By using spherical silica surface-treated with the silane coupling agent, the thermal cycle test resistance and storage stability of the photosensitive composition are improved, and the shape of the inner wall surface when a via is formed is made smooth. Can do.

The spherical shape is not a needle shape, a columnar shape, or an indefinite shape, but may be rounded, and includes a true spherical shape.
It can be confirmed that the filler is spherical by observing with a scanning electron microscope (SEM).

There is no restriction | limiting in particular as a volume average particle diameter of the primary particle of the said filler, Although it can select suitably according to the objective, 0.05 micrometer-3 micrometers are preferable and 0.1 micrometer-1 micrometer are more preferable. If the volume average particle size of the primary particles of the filler is less than 0.05 μm, thixotropy is developed, and the workability may be greatly reduced. If the volume average particle size is greater than 3 μm, the maximum particle size may be increased. . On the other hand, if the volume average particle size of the primary particles of the filler is within the more preferable range, it is advantageous because foreign matters and defects of the cured film can be prevented.
The volume average particle size of the primary particles of the filler can be measured by a dynamic light scattering particle size distribution measuring device.

-Surface treatment-
There is no restriction | limiting in particular as said surface treatment, Although it can select suitably according to the objective, The process which coat | covers a silica with a silane coupling agent is preferable.
There is no restriction | limiting in particular as a process which coat | covers a silica with the said silane coupling agent, Although it can select suitably according to the objective, A methacryl silane process, an amino silane process, and an epoxy silane process are preferable, A methacryl silane process, an amino silane process Is more preferable, and epoxysilane treatment is particularly preferable.

--Silane coupling agent--
The silane coupling agent is not particularly limited and may be appropriately selected depending on the intended purpose. However, at least one functional group selected from an alkoxysilyl group, a chlorosilyl group, and an acetoxysilyl group (hereinafter, “ "Also referred to as" first functional group ") and at least one functional group selected from a (meth) acryloyl group, an amino group and an epoxy group (hereinafter also referred to as" second functional group "). The second functional group is more preferably a (meth) acryloyl group or an amino group, and the second functional group is particularly preferably a (meth) acryloyl group. When the second functional group is a (meth) acryloyl group, it is advantageous in terms of storage stability and TCT resistance.

  Further, as described in JP-B-7-68256, the first functional group is at least one selected from an alkoxysilyl group, a chlorosilyl group, and an acetoxysilyl group, and the second functional group is an imidazole group or an alkyl group. Those having at least one selected from an imidazole group and a vinylimidazole group can also be preferably used.

  The silane coupling agent is not particularly limited. For example, γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl)- γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, JP 7- [Alpha]-[[3- (trimethoxysilyl) propoxy] methyl] -imidazol-1-ethanol, 2-ethyl-4-methyl- [alpha]-[[3- (trimethoxysilyl) propoxy] described in Japanese Patent No. 68256 Methyl] -imidazole-1-ethanol, 4-vinyl-α-[[3- ( Trimethoxy silyl) propoxy] methyl] - imidazole-1-ethanol, 2-ethyl-4-methyl-imidazo trimethoxysilane, and salts thereof, intramolecular condensates, such intermolecular condensates are preferably exemplified. These may be used individually by 1 type and may be used in combination of 2 or more types.

The surface treatment of the spherical silica with the silane coupling agent may be performed only on the spherical silica in advance (this case is hereinafter also referred to as “pretreatment”), or other components in the photosensitive composition. You may carry out together with a part or all of.
There is no restriction | limiting in particular as the method of performing the said pretreatment, For example, methods, such as a dry method, the aqueous solution method, the organic-solvent method, a spray method, are mentioned. The temperature at which the pretreatment is performed is not particularly limited, but is preferably from room temperature to 200 ° C.
It is also preferable to add a catalyst during the pretreatment. There is no restriction | limiting in particular as this catalyst, For example, an acid, a base, a metal compound, an organometallic compound etc. are mentioned.

  The amount of the silane coupling agent to be added in the pretreatment is not particularly limited, but is preferably in the range of 0.01 to 50 parts by weight with respect to 100 parts by weight of spherical silica, and 0.05 parts by weight. The range of part-50 mass parts is more preferable. When the addition amount is less than 0.01 parts by mass, the surface treatment may not be sufficient, and the desired effect may not be obtained. When the addition amount exceeds 50 parts by mass, spherical silica tends to aggregate and be handled. May decrease.

  In the silane coupling agent, the first functional group reacts with the substrate surface, the spherical silica surface, and the active group of the binder, and the second functional group further includes a carboxyl group and an ethylenically unsaturated group of the binder. Therefore, it has the effect of improving the adhesion between the substrate and the photosensitive layer. On the other hand, since the silane coupling agent is highly reactive, when it is added to the photosensitive composition, the second functional group mainly reacts or deactivates during storage due to the diffusion action, Shelf life and pot life may be shortened.

  However, as described above, if the spherical silica pretreated with a silane coupling agent is used, the diffusion effect is suppressed, so that the shelf life and pot life problems are greatly improved. It is also possible to do. Furthermore, when pre-treating spherical silica, conditions such as stirring conditions, temperature conditions, and use of a catalyst can be freely selected, so that the silane coupling agent is compared with the case of adding without pre-treatment. The reaction rate between the first functional group and the active group in the spherical silica can be remarkably increased. Therefore, very good results can be obtained particularly in severe required characteristics such as electroless gold plating, electroless solder plating, and moisture resistance load test. Moreover, the amount of the silane coupling agent used can be reduced by performing the pretreatment, and the shelf life and pot life can be further improved.

Examples of spherical silica that can be used in the present invention and that can be treated with a silane coupling agent include, for example, Electrochemical Industry: FB, SFP series, Tatsumori: 1-FX, Toa Gosei: HSP series, Fuso Chemical Industries: SP Series, Admatechs: Admafine series.
There is no restriction | limiting in particular as content in the said photosensitive composition solid content of the said filler, Although it can select suitably according to the objective, 1 mass%-60 mass% are preferable. When the addition amount is less than 1% by mass, the linear expansion coefficient may not be sufficiently reduced. When the addition amount exceeds 60% by mass, when the cured film is formed on the surface of the photosensitive layer, The film quality becomes fragile, and when a wiring is formed using a permanent pattern, the function of the wiring as a protective film may be impaired.

<Polymerizable compound>
There is no restriction | limiting in particular as said polymeric compound, Although it can select suitably according to the objective, For example, the compound which has one or more ethylenically unsaturated bonds is preferable.

  Examples of the ethylenically unsaturated bond include (meth) acryloyl groups, (meth) acrylamide groups, styryl groups, vinyl groups such as vinyl esters and vinyl ethers; and allyl groups such as allyl ethers and allyl esters.

  The compound having one or more ethylenically unsaturated bonds is not particularly limited and may be appropriately selected depending on the intended purpose. For example, at least one selected from monomers having a (meth) acryl group is Preferably mentioned.

  There is no restriction | limiting in particular as a monomer which has the said (meth) acryl group, According to the objective, it can select suitably, For example, polyethyleneglycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meth) ) Monofunctional acrylates and monofunctional methacrylates such as acrylates; polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, trimethylolpropane diacrylate, neopentylglycol di (Meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, dipentaerythritol penta (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, tri (acryloyloxyethyl) isocyanurate, tri (acryloyloxyethyl) cyanurate, glycerin Poly (functional) alcohols such as tri (meth) acrylate, trimethylolpropane, glycerin, bisphenol, etc., which are subjected to addition reaction with ethylene oxide and propylene oxide, and converted to (meth) acrylate, Japanese Patent Publication No. 48-41708, Japanese Patent Publication No. 50- Urethane acrylates described in JP-A-6034, JP-A-51-37193, etc .; JP-A-48-64183, JP-B-49-43191, JP-B-52-30 Polyester acrylates described in each publication of such 90 No.; and epoxy resin and (meth) polyfunctional acrylates or methacrylates such as epoxy acrylates which are reaction products of acrylic acid. Among these, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and dipentaerythritol penta (meth) acrylate are particularly preferable.

  There is no restriction | limiting in particular as content in the said photosensitive composition solid content of the said polymeric compound, Although it can select suitably according to the objective, 5 mass%-50 mass% are preferable, and 10 mass%- 40 mass% is more preferable. When the content is 5% by mass or more, developability and exposure sensitivity are good, and when the content is 50% by mass or less, the adhesiveness of the photosensitive layer can be prevented from becoming too strong.

<Thermal crosslinking agent>
The thermal cross-linking agent is not particularly limited, and may be appropriately selected within a range that does not adversely affect developability in order to improve the film strength after curing of the photosensitive layer formed using the photosensitive resin composition. You can choose. As the thermal crosslinking agent, at least one selected from an epoxy resin, an oxetane resin, a bismaleimide resin, a cyanate resin, a benzocyclobutene resin, a bisallylnadiimide resin, and a benzoxazine resin is used for workability and a cured product. It is preferable in terms of heat resistance.

  Examples of the epoxy resin include an epoxy resin having at least two oxirane groups in one molecule and an epoxy resin having at least two epoxy groups having an alkyl group at the β-position in one molecule.

  Examples of the epoxy resin having at least two oxirane groups in one molecule include, for example, a bixylenol type or biphenol type epoxy resin (“YX4000 Japan Epoxy Resin” etc.) or a mixture thereof, a complex having an isocyanurate skeleton, etc. Cyclic epoxy resin (“TEPIC; manufactured by Nissan Chemical Industries, Ltd.”, “Araldite PT810; manufactured by Ciba Specialty Chemicals”, etc.), bisphenol A type epoxy resin, novolac type epoxy resin, bisphenol F type epoxy resin, hydrogenated Bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, halogenated epoxy resin (for example, low brominated epoxy resin, high halogenated epoxy resin) Brominated phenol novolac type epoxy resin, etc.), allyl group-containing bisphenol A type epoxy resin, trisphenol methane type epoxy resin, diphenyldimethanol type epoxy resin, phenol biphenylene type epoxy resin, dicyclopentadiene type epoxy resin ("HP-7200"). , HP-7200H; manufactured by Dainippon Ink Chemical Co., Ltd., etc.), glycidylamine type epoxy resins (diaminodiphenylmethane type epoxy resins, diglycidylaniline, triglycidylaminophenol, etc.), glycidyl ester type epoxy resins (diphthalic acid diphthalate) Glycidyl ester, adipic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, dimer acid diglycidyl ester, etc.), hydantoin type epoxy resin, alicyclic epoxy resin (3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, bis (3,4-epoxycyclohexylmethyl) adipate, “GT-300, GT-400, ZEHPE3150; manufactured by Daicel Chemical Industries, Ltd.” ), Imide type alicyclic epoxy resin, bisphenol A novolac type epoxy resin, tetraphenylolethane type epoxy resin, glycidyl phthalate resin, tetraglycidyl xylenoyl ethane resin, naphthalene group-containing epoxy resin (naphthol aralkyl type epoxy resin) , Naphthol novolac type epoxy resin, tetrafunctional naphthalene type epoxy resin, commercially available products are “ESN-190, ESN-360; manufactured by Nippon Steel Chemical Co., Ltd.”, “HP-4032, EXA-4750, EXA-470. 0; manufactured by Dainippon Ink & Chemicals, Inc.), a reaction product of a polyphenol compound obtained by addition reaction of a phenol compound with a diolefin compound such as divinylbenzene or dicyclopentadiene, and epichlorohydrin, 4-vinylcyclohexene- 1-oxide ring-opening polymer epoxidized with peracetic acid or the like, linear phosphorus-containing epoxy resin, cyclic phosphorus-containing epoxy resin, α-methylstilbene-type liquid crystal epoxy resin, dibenzoyloxybenzene Type liquid crystal epoxy resin, azophenyl type liquid crystal epoxy resin, azomethine phenyl type liquid crystal epoxy resin, binaphthyl type liquid crystal epoxy resin, azine type epoxy resin, glycidyl methacrylate copolymer epoxy resin (“CP-50S, CP-50M; NOF Corporation) `` Made in company '' etc. , Copolymerized epoxy resins of cyclohexylmaleimide and glycidyl methacrylate, bis (glycidyloxyphenyl) fluorene epoxy resin, bis the like (glycidyloxyphenyl) adamantane type epoxy resins, is not limited thereto. These epoxy resins may be used individually by 1 type, and may use 2 or more types together.

In addition to the epoxy resin having at least two oxirane groups in one molecule, an epoxy resin containing at least two epoxy groups having an alkyl group at the β-position can be used, and the β-position is an alkyl group. Particularly preferred is a compound containing an epoxy group substituted with a (specifically, a β-alkyl-substituted glycidyl group or the like).
In the epoxy resin containing at least an epoxy group having an alkyl group at the β-position, all of two or more epoxy groups contained in one molecule may be β-alkyl-substituted glycidyl groups, and at least one epoxy group May be a β-alkyl-substituted glycidyl group.

Examples of the oxetane resin include oxetane resins having at least two oxetanyl groups in one molecule.
Specifically, for example, bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, 1,4-bis [(3-methyl- 3-Oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) In addition to polyfunctional oxetanes such as methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate or oligomers or copolymers thereof, compounds having an oxetane group; Novolac resin, poly (p-hydroxystyrene), cardo type bisphenol , Calixarenes, calixresorcinarenes, and ether compounds such as silsesquioxane and other hydroxyl group-containing resins. In addition to these, an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate A polymer etc. are also mentioned.

  Examples of the bismaleimide resin include 4,4′-diphenylmethane bismaleimide, bis- (3-ethyl-5-methyl-4-maleimidophenyl) methane, and 2,2′-bis- [4- (4-maleimide). Phenoxy) phenyl] propane, and the like.

  Examples of the cyanate resin include bis A type cyanate resin, bis F type cyanate resin, cresol novolac type cyanate resin, phenol novolac type cyanate resin, and the like.

  In addition, examples of the high heat resistant material include benzocyclobutene (BCB), bisallyl nadiimide (BANI), and benzoxazine.

<Elastomer>
The photosensitive composition preferably includes an elastomer.
By containing the elastomer, it is possible to further improve the adhesion with the conductor layer of the printed wiring board when the photosensitive resin composition is used for the solder resist, and the heat resistance of the cured film, thermal shock resistance, Flexibility and toughness can be further improved.

  There is no restriction | limiting in particular as said elastomer, According to the objective, it can select suitably, For example, a styrene elastomer, an olefin elastomer, a urethane elastomer, a polyester elastomer, a polyamide elastomer, an acrylic elastomer, a silicone elastomer Etc. These elastomers are composed of a hard segment component and a soft segment component. In general, the former contributes to heat resistance and strength, and the latter contributes to flexibility and toughness. Among these, polyester elastomers are advantageous in terms of compatibility with other materials.

  Examples of the styrenic elastomer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, and the like. As a component constituting the styrene-based elastomer, styrene derivatives such as α-methylstyrene, 3-methylstyrene, 4-propylstyrene, and 4-cyclohexylstyrene can be used in addition to styrene. Specifically, Tufprene, Solprene T, Asaprene T, Tuftec (Asahi Kasei Kogyo Co., Ltd.), Elastomer AR (Aron Kasei Co., Ltd.), Clayton G, Super Reflex (October, Shell Japan Co., Ltd.), JSR- TR, TSR-SIS, Dynalon (manufactured by Nippon Synthetic Rubber Co., Ltd.), Denka STR (manufactured by Denki Kagaku Co., Ltd.), Quintac (manufactured by Nippon Zeon Co.), TPE-SB series (manufactured by Sumitomo Chemical Co., Ltd.) Examples include Lavalon (manufactured by Mitsubishi Chemical Corporation), Septon, Hybler (manufactured by Kuraray Co., Ltd.), Sumiflex (manufactured by Sumitomo Bakelite Co., Ltd.), Rheostomer, Actimer (manufactured by Riken Vinyl Industry Co., Ltd.)

  The olefin elastomer is a copolymer of an α-olefin having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-pentene, for example, an ethylene-propylene copolymer ( EPR), ethylene-propylene-diene copolymer (EPDM) and the like. The olefin-based elastomer includes dicyclopentadiene, 1,4-hexadiene, cyclooctanediene, methylene norbornene, ethylidene norbornene, butadiene, isoprene, and the like. Examples include coalesced and epoxidized polybutadiene. Examples of the olefin-based elastomer include carboxy-modified NBR obtained by copolymerizing butadiene-acrylonitrile copolymer with methacrylic acid. Further, as the olefin elastomer, ethylene-α-olefin copolymer rubber, ethylene-α-olefin-nonconjugated diene copolymer rubber, propylene-α-olefin copolymer rubber, butene-α-olefin copolymer Rubber etc. are mentioned.

  Specific examples of the olefin elastomer include Miralasta (Mitsui Petrochemical), EXACT (Exxon Chemical), ENGAGE (Dow Chemical), hydrogenated styrene-butadiene rubber “DYNABON HSBR” (Nippon Synthetic Rubber) ), Butadiene-acrylonitrile copolymer “NBR series” (manufactured by Nippon Synthetic Rubber Co., Ltd.), “XER series” of both terminal carboxyl group-modified butadiene-acrylonitrile copolymers having a crosslinking point (manufactured by Nippon Synthetic Rubber Co., Ltd.), polybutadiene And BF-1000 (manufactured by Nippon Soda Co., Ltd.) of epoxidized polybudadiene partially epoxidized.

  The urethane elastomer is composed of structural units of a hard segment composed of a low molecular (short chain) diol and a diisocyanate and a soft segment composed of a high molecular (long chain) diol and a diisocyanate. Examples of the polymer (long chain) diol include polypropylene glycol, polytetramethylene oxide, poly (1,4-butylene adipate), poly (ethylene-1,4-butylene adipate), polycaprolactone, and poly (1,6-hexene). Xylene carbonate), poly (1,6-hexylene-neopentylene adipate) and the like. The number average molecular weight of the polymer (long chain) diol is preferably 500 to 10,000. Examples of the low molecular (short chain) diol include ethylene glycol, propylene glycol, 1,4-butanediol, and bisphenol A. The number average molecular weight of the short-chain diol is preferably 48 to 500. Specific examples of the urethane elastomer include PANDEX T-2185, T-2983N (manufactured by Dainippon Ink & Chemicals, Inc.), sylactolan E790, and the like.

  The polyester elastomer is obtained by polycondensation of a dicarboxylic acid or a derivative thereof and a diol compound or a derivative thereof. Specific examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid, and aromatic dicarboxylic acids in which hydrogen atoms of these aromatic rings are substituted with a methyl group, an ethyl group, a phenyl group, and the like, Examples thereof include aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid and dodecanedicarboxylic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. These compounds can be used alone or in combination of two or more. Specific examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 1,4-cyclohexanediol; Examples include alicyclic diol, bisphenol A, bis- (4-hydroxyphenyl) -methane, bis- (4-hydroxy-3-methylphenyl) -propane, resorcin and the like. These compounds can be used alone or in combination of two or more. In addition, a multiblock copolymer having an aromatic polyester (for example, polybutylene terephthalate) portion as a hard segment component and an aliphatic polyester (for example, polytetramethylene glycol) portion as a soft segment component can be used. Polyester elastomers are available in various grades depending on the types and ratios of hard segments and soft segments, and the difference in molecular weight. Specific examples of polyester elastomers include Hytrel (Du Pont-Toray), Perprene (Toyobo), Espel (Hitachi Chemical Industries), and the like.

  The polyamide-based elastomer is composed of a hard segment made of polyamide and a soft segment made of polyether or polyester, and is roughly divided into two types: a polyether block amide type and a polyether ester block amide type. Is done. Examples of the polyamide include polyamide 6, polyamide 11, and polyamide 12. Examples of the polyether include polyoxyethylene, polyoxypropylene, polytetramethylene glycol and the like. Specific examples of polyamide-based elastomers include UBE polyamide elastomer (manufactured by Ube Industries), Daiamide (manufactured by Daicel Huls), PEBAX (manufactured by Toray Industries, Inc.), Grilon ELY (manufactured by MMS Japan), and Novamid (manufactured by Mitsubishi Chemical Corporation). ), Glase (Dainippon Ink Chemical Co., Ltd.) and the like.

  The acrylic elastomer is an acrylic ester such as ethyl acrylate, butyl acrylate, methoxyethyl acrylate or ethoxyethyl acrylate, a monomer having an epoxy group such as glycidyl methacrylate or allyl glycidyl ether, and / or vinyl such as acrylonitrile or ethylene. It is obtained by copolymerizing with a monomer. Examples of the acrylic elastomer include acrylonitrile-butyl acrylate copolymer, acrylonitrile-butyl acrylate-ethyl acrylate copolymer, acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer, and the like.

  The silicone elastomer is mainly composed of organopolysiloxane, and is classified into polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. Further, a part of organopolysiloxane modified with a vinyl group, an alkoxy group or the like may be used. Specific examples of the silicone elastomer include KE series (manufactured by Shin-Etsu Chemical Co., Ltd.), SE series, CY series, SH series (above, manufactured by Toray Dow Corning Silicone).

  In addition to the above-mentioned elastomer, a rubber-modified epoxy resin can be used. The rubber-modified epoxy resin is, for example, a part or all of the epoxy groups such as the above-mentioned bisphenol F type epoxy resin, bisphenol A type epoxy resin, salicylaldehyde type epoxy resin, phenol novolac type epoxy resin, or cresol novolak type epoxy resin. Is obtained by modification with carboxylic acid-modified butadiene-acrylonitrile rubber, terminal amino-modified silicone rubber or the like.

  Among the elastomers, from the viewpoint of shear adhesion and thermal shock resistance, both end carboxyl group-modified butadiene-acrylonitrile copolymer, Esper having a hydroxyl group which is a polyester elastomer (Espel 1612, 1620, manufactured by Hitachi Chemical Co., Ltd.), Epoxidized polybutadiene is preferred.

  There is no restriction | limiting in particular as content in the said photosensitive composition solid content of the said elastomer, Although it can select suitably according to the objective, 0.5 mass%-30 mass% are preferable, and 1 mass%- 10 mass% is more preferable and 3 mass%-8 mass% are especially preferable. When the content is within a preferable range, it is advantageous in that the shear adhesiveness and the thermal shock resistance can be further improved.

<Photopolymerization initiator>
The photopolymerization initiator is not particularly limited as long as it has the ability to initiate the polymerization of the polymerizable compound, and can be appropriately selected according to the purpose. Those having photosensitivity are preferable, and may be an activator that generates an active radical by generating some action with a photoexcited sensitizer, and is an initiator that initiates cationic polymerization according to the type of monomer. May be.
The photopolymerization initiator preferably contains at least one component having a molecular extinction coefficient of at least about 50 within a wavelength range of about 300 nm to 800 nm. The wavelength is more preferably 330 nm to 500 nm.
As the photopolymerization initiator, a neutral photopolymerization initiator is used. Moreover, the other photoinitiator may be included as needed.

  The neutral photopolymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably a compound having at least an aromatic group, such as (bis) acylphosphine oxide or an ester thereof. More preferred are acetophenone compounds, benzophenone compounds, benzoin ether compounds, ketal derivative compounds, and thioxanthone compounds. Two or more neutral photopolymerization initiators may be used in combination.

  Examples of the photopolymerization initiator include (bis) acylphosphine oxide or esters thereof, acetophenone compounds, benzophenone compounds, benzoin ether compounds, ketal derivative compounds, thioxanthone compounds, oxime derivatives, organic peroxides, thiols, and the like. Compounds, and the like. Among these, from the viewpoints of the sensitivity and storage stability of the photosensitive layer and the adhesion between the photosensitive layer and the printed wiring board forming substrate, oxime derivatives, (bis) acylphosphine oxide or esters thereof, acetophenone compounds, benzophenone Compounds, benzoin ether compounds, ketal derivative compounds, and thioxanthone compounds are preferred.

Examples of the (bis) acylphosphine oxide include 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylphosphinic acid methyl ester, 2,6 -Dichlorobenzoylphenylphosphine oxide, 2,6-dimethylmethyoxybenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, bis (2,4,6-trimethyl) And benzoyl) -phenylphosphine oxide.
Examples of the acetophenone compounds include acetophenone, methoxyacetophenone, 1-phenyl-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 4-diphenoxydichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one and the like.
Examples of the benzophenone compounds include benzophenone, 4-phenylbenzophenone, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, 3,3′-dimethyl-4-methoxybenzophenone, and diphenoxybenzophenone.
Examples of the benzoin ether compounds include benzoin ethyl ether and benzoin propyl ether.
Examples of the ketal derivative compound include benzyldimethyl ketal.
Examples of the thioxanthone compound include 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, isopropylthioxanthone, and the like.

The said photoinitiator may be used individually by 1 type, and may use 2 or more types together.
The content of the photopolymerization initiator in the solid content of the photosensitive composition is preferably 0.01% by mass to 30% by mass, more preferably 0.1% by mass to 20% by mass, and 0.1% by mass to 15% by mass is particularly preferred.

<Other ingredients>
The other components are not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include a thermosetting accelerator, a thermal polymerization inhibitor, a plasticizer, and a colorant (color pigment or dye). Furthermore, adhesion promoters to the substrate surface and other auxiliary agents (for example, conductive particles, fillers, antifoaming agents, flame retardants, leveling agents, peeling accelerators, antioxidants, perfumes, surface tension modifiers. , Chain transfer agent, etc.) may be used in combination.
By appropriately containing these components, properties such as the stability, photographic properties, and film properties of the intended photosensitive film can be adjusted.
The thermal polymerization inhibitor is described in detail, for example, in paragraphs [0101] to [0102] of JP-A-2008-250074.
The thermosetting accelerator is described in detail in paragraph [0093] of JP-A-2008-250074, for example.
The plasticizer is described in detail, for example, in paragraphs [0103] to [0104] of JP-A-2008-250074.
The colorant is described in detail, for example, in paragraphs [0105] to [0106] of JP-A-2008-250074.
The adhesion promoter is described in detail, for example, in paragraphs [0107] to [0109] of JP-A-2008-250074.

  Hereinafter, a specific example of the present invention will be described taking a case where a photosensitive film is used as an example. The present invention can be used in the form of a liquid register other than the photosensitive film.

(Photosensitive film)
The photosensitive film of the present invention comprises at least a support and a photosensitive layer comprising the photosensitive composition of the present invention on the support, and further comprises other layers as necessary.

-Support-
The support is not particularly limited and may be appropriately selected depending on the intended purpose. However, it is preferable that the photosensitive layer is peelable and has good light transmittance, and further has a smooth surface. Is more preferable.

  The support is preferably made of synthetic resin and transparent, for example, polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyethylene, cellulose triacetate, cellulose diacetate, poly (meth) acrylic acid alkyl ester, poly ( (Meth) acrylic acid ester copolymer, polyvinyl chloride, polyvinyl alcohol, polycarbonate, polystyrene, cellophane, polyvinylidene chloride copolymer, polyamide, polyimide, vinyl chloride / vinyl acetate copolymer, polytetrafluoroethylene, polytrifluoro Various plastic films, such as ethylene, a cellulose film, and a nylon film, are mentioned, Among these, polyethylene terephthalate is particularly preferable. These may be used alone or in combination of two or more.

  There is no restriction | limiting in particular in the thickness of the said support body, Although it can select suitably according to the objective, For example, 2 micrometers-150 micrometers are preferable, 5 micrometers-100 micrometers are more preferable, 8 micrometers-50 micrometers are especially preferable.

  There is no restriction | limiting in particular as a shape of the said support body, Although it can select suitably according to the objective, A long shape is preferable. There is no restriction | limiting in particular in the length of the said elongate support body, For example, the thing of the length of 10m-20,000m is mentioned.

-Photosensitive layer-
If the said photosensitive layer is a layer which consists of photosensitive compositions, there will be no restriction | limiting in particular, According to the objective, it can select suitably.
Further, the number of laminated photosensitive layers is not particularly limited and may be appropriately selected depending on the purpose. For example, it may be one layer or two or more layers.

  As a method for forming the photosensitive layer, a photosensitive composition solution is prepared by dissolving, emulsifying or dispersing the photosensitive composition of the present invention in water or a solvent on the support, and the solution is directly applied. The method of laminating | stacking by apply | coating and drying is mentioned.

  There is no restriction | limiting in particular as a solvent of the said photosensitive composition solution, According to the objective, it can select suitably, For example, methanol, ethanol, normal-propanol, isopropanol, normal-butanol, secondary butanol, normal-hexanol etc. Alcohols; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diisobutyl ketone, and the like ketones; ethyl acetate, butyl acetate, acetic acid-normal-amyl, methyl sulfate, ethyl propionate, dimethyl phthalate, ethyl benzoate, and methoxy Esters such as propyl acetate; aromatic hydrocarbons such as toluene, xylene, benzene, ethylbenzene; carbon tetrachloride, trichloroethylene, chloroform, 1,1,1-trichloroethane, methylene chloride Halogenated hydrocarbons such as monochlorobenzene; ethers such as tetrahydrofuran, diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 1-methoxy-2-propanol; dimethylformamide, dimethylacetamide, dimethylsulfoxide, sulfolane, etc. Is mentioned. These may be used alone or in combination of two or more. Moreover, you may add a well-known surfactant.

The application method is not particularly limited and may be appropriately selected depending on the intended purpose. For example, using a spin coater, slit spin coater, roll coater, die coater, curtain coater, etc. The method of apply | coating is mentioned.
The drying conditions vary depending on each component, the type of solvent, the use ratio, and the like, but are usually about 60 seconds to 110 ° C. for about 30 seconds to 15 minutes.

  There is no restriction | limiting in particular as thickness of the said photosensitive layer, Although it can select suitably according to the objective, For example, 1 micrometer-100 micrometers are preferable, 2 micrometers-50 micrometers are more preferable, and 4 micrometers-30 micrometers are especially preferable.

<Other layers>
The other layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a protective film, a thermoplastic resin layer, a barrier layer, a release layer, an adhesive layer, a light absorbing layer, a surface protective layer, etc. Layer. The said photosensitive film may have these layers individually by 1 type, and may have 2 or more types.

<< Protective film >>
The photosensitive film may form a protective film on the photosensitive layer.
Examples of the protective film include those used for the support, paper, paper laminated with polyethylene, polypropylene, and the like. Among these, polyethylene film and polypropylene film are preferable.
There is no restriction | limiting in particular in the thickness of the said protective film, Although it can select suitably according to the objective, For example, 5 micrometers-100 micrometers are preferable, 8 micrometers-50 micrometers are more preferable, 10 micrometers-30 micrometers are especially preferable.
Examples of the combination of the support and the protective film (support / protective film) include polyethylene terephthalate / polypropylene, polyethylene terephthalate / polyethylene, polyvinyl chloride / cellophane, polyimide / polypropylene, polyethylene terephthalate / polyethylene terephthalate, and the like. . Moreover, interlayer adhesion can be adjusted by surface-treating at least one of the support and the protective film. The surface treatment of the support may be performed in order to increase the adhesive force with the photosensitive layer. For example, coating of a primer layer, corona discharge treatment, flame treatment, ultraviolet irradiation treatment, high frequency irradiation treatment, glow treatment Examples thereof include a discharge irradiation process, an active plasma irradiation process, and a laser beam irradiation process.

Moreover, 0.3-1.4 are preferable and the static friction coefficient of the said support body and the said protective film has more preferable 0.5-1.2.
If the static friction coefficient is 0.3 or more, it is possible to prevent the occurrence of winding misalignment when it is made into a roll shape due to excessive slip, and if it is 1.4 or less, it can be wound into a good roll shape. .

  For example, the photosensitive film is preferably wound around a cylindrical core, wound into a long roll, and stored. There is no restriction | limiting in particular in the length of the said elongate photosensitive film, For example, it can select suitably from the range of 10m-20,000m. Further, slitting may be performed so that the user can easily use, and a long body in the range of 100 m to 1,000 m may be formed into a roll. In this case, it is preferable that the support is wound up so as to be the outermost side. Moreover, you may slit the said roll-shaped photosensitive film in a sheet form. From the viewpoint of protecting the end face and preventing edge fusion during storage, it is preferable to install a separator (especially moisture-proof and desiccant-containing) on the end face, and use a low moisture-permeable material for packaging. It is preferable.

  The protective film may be surface-treated in order to adjust the adhesion between the protective film and the photosensitive layer. In the surface treatment, for example, an undercoat layer made of a polymer such as polyorganosiloxane, fluorinated polyolefin, polyfluoroethylene, or polyvinyl alcohol is formed on the surface of the protective film. The undercoat layer can be formed by applying the polymer coating solution to the surface of the protective film and then drying at 30 ° C. to 150 ° C. for 1 to 30 minutes. As for the temperature in the case of the said drying, 50 to 120 degreeC is especially preferable.

(Photosensitive laminate)
The photosensitive laminate includes at least a base and a photosensitive layer provided on the base, and is formed by stacking other layers appropriately selected according to the purpose.
The photosensitive layer is transferred from the photosensitive film produced by the manufacturing method described above, and has the same configuration as described above.

<Substrate>
The substrate is a substrate to be processed on which a photosensitive layer is formed, or a member to be transferred onto which at least the photosensitive layer of the photosensitive film of the present invention is transferred. For example, it can be arbitrarily selected from those having high surface smoothness to those having a rough surface. A plate-like substrate is preferable, and a so-called substrate is used. Specific examples include known printed wiring board manufacturing substrates (printed substrates), glass plates (soda glass plates, etc.), synthetic resin films, paper, metal plates, and the like.

<Method for producing photosensitive laminate>
Examples of the method for producing the photosensitive laminate include a method in which at least the photosensitive layer in the photosensitive film of the present invention is transferred and laminated while performing at least one of heating and pressing.

In the method for producing a photosensitive laminate, the photosensitive film of the present invention is laminated on the surface of the substrate while at least one of heating and pressing. In addition, when the said photosensitive film has the said protective film, it is preferable to peel this protective film and to laminate | stack so that the said photosensitive layer may overlap with the said base | substrate.
There is no restriction | limiting in particular in the said heating temperature, According to the objective, it can select suitably, For example, 15 to 180 degreeC is preferable and 60 to 140 degreeC is more preferable.
There is no restriction | limiting in particular in the pressure of the said pressurization, According to the objective, it can select suitably, For example, 0.1 MPa-1.0 MPa are preferable and 0.2 MPa-0.8 MPa are more preferable.

  There is no restriction | limiting in particular as an apparatus which performs at least any one of the said heating, According to the objective, it can select suitably, For example, Laminator (For example, Taisei Laminator Co., Ltd. product, VP-II, Nichigo Morton Co., Ltd. product, VP130) is preferable.

  The photosensitive film and the photosensitive laminate of the present invention have a uniform film thickness and an extremely low occurrence rate of planar defects such as pinholes and repellency, so that they have excellent insulation reliability and high-definition permanent patterns (protection) Film, interlayer insulating film, solder resist pattern, etc.) can be formed efficiently. Therefore, it can be widely used for forming a high-definition permanent pattern in the field of electronic materials, and can be suitably used particularly for forming a permanent pattern on a printed circuit board.

(Permanent pattern forming method)
The permanent pattern forming method of the present invention includes at least an exposure step, and further includes other steps such as a development step appropriately selected as necessary.

<Exposure process>
The said exposure process is a process of exposing with respect to the photosensitive layer in the photosensitive laminated body of this invention. The photosensitive laminate of the present invention is as described above.

  The exposure target is not particularly limited as long as it is a photosensitive layer in the photosensitive laminate, and can be appropriately selected according to the purpose. For example, as described above, a photosensitive film is formed on a substrate. It is preferably performed on a laminate formed by laminating while performing at least one of heating and pressurization.

  There is no restriction | limiting in particular as said exposure, According to the objective, it can select suitably, Digital exposure, analog exposure, etc. are mentioned, Among these, digital exposure is preferable.

<Other processes>
There is no restriction | limiting in particular as said other process, According to the objective, it can select suitably, For example, the surface treatment process of a base material, a development process, a hardening process process, a post exposure process etc. are mentioned.

<< Development process >>
The development is performed by removing an unexposed portion of the photosensitive layer.
There is no restriction | limiting in particular as the removal method of the said unhardened area | region, According to the objective, it can select suitably, For example, the method etc. which remove using a developing solution are mentioned.

  There is no restriction | limiting in particular as said developing solution, Although it can select suitably according to the objective, For example, alkaline aqueous solution, an aqueous developing solution, an organic solvent etc. are mentioned, Among these, weakly alkaline aqueous solution is preferable. Examples of the basic component of the weak alkaline aqueous solution include lithium hydroxide, sodium hydroxide, potassium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, lithium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium phosphate, phosphorus Examples include potassium acid, sodium pyrophosphate, potassium pyrophosphate, and borax.

The pH of the weak alkaline aqueous solution is, for example, preferably 8-12, more preferably 9-11. As said weak alkaline aqueous solution, 0.1 mass%-5 mass% sodium carbonate aqueous solution or potassium carbonate aqueous solution etc. are mentioned, for example.
The temperature of the developer can be appropriately selected according to the developability of the photosensitive layer, and is preferably about 25 ° C. to 40 ° C., for example.

  The developer includes a surfactant, an antifoaming agent, an organic base (for example, ethylenediamine, ethanolamine, tetramethylammonium hydroxide, diethylenetriamine, triethylenepentamine, morpholine, triethanolamine, etc.) and development. Therefore, it may be used in combination with an organic solvent (for example, alcohols, ketones, esters, ethers, amides, lactones, etc.). The developer may be an aqueous developer obtained by mixing water or an aqueous alkali solution and an organic solvent, or may be an organic solvent alone.

<< Curing treatment process >>
The curing treatment step is a step of performing a curing treatment on the photosensitive layer in the formed pattern after the development step is performed.
There is no restriction | limiting in particular as said hardening process, Although it can select suitably according to the objective, For example, a whole surface exposure process, a whole surface heat processing, etc. are mentioned suitably.

Examples of the entire surface exposure processing method include a method of exposing the entire surface of the laminate on which the permanent pattern is formed after the development. The entire surface exposure accelerates the curing of the resin in the photosensitive composition forming the photosensitive layer, and the surface of the permanent pattern is cured.
There is no restriction | limiting in particular as an apparatus which performs the said whole surface exposure, Although it can select suitably according to the objective, For example, UV exposure machines, such as an ultrahigh pressure mercury lamp, are mentioned suitably.

Examples of the entire surface heat treatment method include a method of heating the entire surface of the laminate on which the permanent pattern is formed after the development. By heating the entire surface, the film strength of the surface of the permanent pattern is increased.
The heating temperature in the entire surface heating is preferably 120 ° C to 250 ° C, more preferably 120 ° C to 200 ° C. When the heating temperature is 120 ° C. or higher, the film strength is improved by heat treatment, and when the heating temperature is 250 ° C. or lower, the resin in the photosensitive composition is decomposed to prevent the film quality from being weak and brittle.
The heating time in the entire surface heating is preferably 10 minutes to 120 minutes, more preferably 15 minutes to 60 minutes.
There is no restriction | limiting in particular as an apparatus which performs the said whole surface heating, According to the objective, it can select suitably from well-known apparatuses, For example, a dry oven, a hot plate, IR heater etc. are mentioned.

When the permanent pattern forming method is a permanent pattern forming method for forming at least one of a protective film, an interlayer insulating film, and a solder resist pattern, the permanent pattern is formed on the printed wiring board by the permanent pattern forming method. Further, soldering can be performed as follows.
That is, by the development, a hardened layer that is the permanent pattern is formed, and the metal layer is exposed on the surface of the printed wiring board. Gold plating is performed on the portion of the metal layer exposed on the surface of the printed wiring board, and then soldering is performed. Then, a semiconductor or a component is mounted on the soldered portion. At this time, the permanent pattern by the hardened layer exhibits a function as a protective film, an insulating film (interlayer insulating film), or a solder resist, and prevents external impact and conduction between adjacent electrodes.

(Printed board)
The printed circuit board of the present invention comprises at least a substrate and a permanent pattern formed by the permanent pattern forming method, and further has other configurations appropriately selected as necessary.
There is no restriction | limiting in particular as another structure, According to the objective, it can select suitably, For example, the buildup board | substrate etc. in which the insulating layer was further provided between the base material and the said permanent pattern are mentioned.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

Example 1
-Production of photosensitive film-
On a 16 μm thick polyethylene terephthalate film (16FB50, manufactured by Toray Industries, Inc.) as a support, a photosensitive composition solution having the following composition was applied and dried, and a 30 μm thick photosensitive film was formed on the support. A layer was formed. On the photosensitive layer, as a protective layer, a polypropylene film having a thickness of 20 μm (manufactured by Oji Specialty Paper Co., Ltd., Alphan E-200) was laminated to produce a photosensitive film.

-Composition of photosensitive composition solution-
Binder (ZAR-2039H, manufactured by Nippon Kayaku Co., Ltd., solid content concentration 60%; bisphenol A type epoxy acrylate) 35.6 parts by mass Polymerizable compound (DPHA, manufactured by Nippon Kayaku Co., Ltd.) -2.57 parts by mass-Thermal crosslinking agent (Epototo YDF-170, manufactured by Tohto Kasei Co., Ltd., bisphenol F type epoxy resin) ... 3.95 parts by mass-Melamine ... 1.38 parts by mass-Irgacure 907 (manufactured by Ciba Specialty Chemicals) ... 0.97 parts by mass-DETX-S (Nippon Kayaku Co., Ltd.) ... 0.009 parts by mass-Filler 1 (SC-2500-SMJ; spherical silica; methacryl Silane treatment 1%; volume average particle size of primary particles 0.5 μm; manufactured by Admatechs Co., Ltd. 24.78 parts by mass Elastomer (Esper 1620, Japan) 9.48 parts by mass-Phthalocyanine blue ... 0.15 parts by mass-30% by weight methyl ethyl ketone solution of MegaFuck F-780F (manufactured by Dainippon Ink & Chemicals, Inc.) 0.15 parts by mass Normal propyl acetate (solvent) 32.90 parts by mass

-Lamination on substrate-
The substrate was prepared by subjecting a surface of a copper clad laminate (no through hole, copper thickness: 12 μm) to chemical polishing. A vacuum laminator (manufactured by Nichigo Morton Co., Ltd., VP130) was used on the copper-clad laminate while peeling off the protective film from the photosensitive film so that the photosensitive layer of the photosensitive film was in contact with the copper-clad laminate. Thus, a laminate in which the copper-clad laminate, the photosensitive layer, and the polyethylene terephthalate film (support) were laminated in this order was prepared.
The pressure bonding conditions were a vacuum drawing time of 40 seconds, a pressure bonding temperature of 70 ° C., a pressure bonding pressure of 0.2 MPa, and a pressure application time of 10 seconds.

(Example 2)
A photosensitive film and a laminate were produced in the same manner as in Example 1 except that the filler 1 used in Example 1 was replaced with the filler 2 described below.
-Filler 2-
As the filler 2, CSR-1205-CB (spherical silica; methacrylsilane treatment 2%; volume average particle size of primary particles 0.5 μm; manufactured by Tatsumori Co., Ltd.) was used.

(Example 3)
A photosensitive film and a laminate were produced in the same manner as in Example 1 except that the filler 1 used in Example 1 was replaced with the filler 3 described below.
-Filler 3-
As the filler 3, CSR-1062-CB (spherical silica; 0.6% aminosilane treatment; volume average particle size of primary particles: 0.5 μm; manufactured by Tatsumori Co., Ltd.) was used.

Example 4
A photosensitive film and a laminate were produced in the same manner as in Example 1 except that the filler 1 used in Example 1 was replaced with the filler 4 described below.
-Filler 4-
As the filler 4, SC-2500-SEJ (spherical silica; epoxysilane treatment 1%; volume average particle size of primary particles 0.5 μm; manufactured by Admatechs) was used.

(Example 5)
A photosensitive film and a laminate were produced in the same manner as in Example 1 except that the filler 1 used in Example 1 was replaced with the filler 5 described below.
-Filler 5-
As the filler 5, CSR-1061-CB (spherical silica; epoxy silane treatment 0.6%; volume average particle size of primary particles 0.5 μm; manufactured by Admatex) was used.

(Examples 6 to 10)
Example 1 except that the binder ZAR-2039H was used in Examples 1 to 5 except that the binder ZFR-1401H (manufactured by Nippon Kayaku Co., Ltd., solid content concentration 60%; bisphenol F type epoxy acrylate) was used. To 5 to produce photosensitive films and laminates of Examples 6 to 10.

(Comparative Example 1)
In Example 1, the photosensitive film and the laminated body were produced like Example 1 except having replaced the point which used the filler 1 with the following filler 6. FIG.
-Filler 6
As the filler 6, SO-C2 (spherical silica; no surface treatment; volume average particle size of primary particles: 0.5 μm; manufactured by Admatechs) was used.

(Comparative Example 2)
A photosensitive film and a laminate were produced in the same manner as in Example 1 except that the filler 1 used in Example 1 was replaced with the following filler 7.
-Filler 7-
As the filler 7, RAC-1000 (epoxysilane treatment, non-spherical silica; manufactured by Tatsumori Co., Ltd.) was used.

(Comparative Example 3)
In Example 1, the point where the binder ZAR-2039 was used was replaced with a binder PR-300 (manufactured by Showa Polymer Co., Ltd., solid content concentration 60%) having no bisphenol A type or bisphenol F type skeleton. Except for the above, a photosensitive film and a laminate were produced in the same manner as in Example 1.

  With respect to the obtained laminate and the like, thermal cycle test resistance, storage stability, and the shape of the inner wall surface when vias were formed were evaluated as follows. The results are shown in Table 1.

<Thermal cycle test resistance>
A photosensitive film was formed by vacuum laminating a photosensitive film on an FR-5 substrate having been etched with a copper foil. Thereafter, exposure / development was performed to form 27 2 mm square resist patterns (bending radius R = 0). Post exposure (1000 mJ / cm ² ) and post bake (150 ° C./1 h) were performed to prepare an evaluation substrate. The evaluation board | substrate was put into the thermal cycle machine with which a temperature cycle is performed between -65 degreeC and 150 degreeC, the number of the resist patterns which the crack generate | occur | produced at 300 cycles was measured, and the crack generation rate was computed.

<Storage stability>
The photosensitive film was stored at 40 ° C. for 2 days. The laminate was laminated on a copper clad laminate, and the shortest development time _tr was measured. The smaller the ratio r = t _r / t ₀ to the shortest development time t ₀ before storage, the better the storage stability.
The shortest development time is that the polyethylene terephthalate film (support) is peeled off from the laminate, and a 1 mass% sodium carbonate aqueous solution at 30 ° C. is applied to the entire surface of the photosensitive layer on the copper clad laminate at a pressure of 0.15 MPa. The time required from the start of spraying of the aqueous sodium carbonate solution until the photosensitive layer on the copper clad laminate was dissolved and removed was measured, and this was taken as the shortest development time.
〔Evaluation criteria〕
○: r is 1.5 or less, and the storage stability is excellent.
(Circle) (triangle | delta): r is larger than 1.5 and below 2.0, and storage stability is favorable.
Δ ×: r is larger than 2.0 and 2.5 or smaller, and the storage stability is slightly inferior.
X: r is larger than 2.5 and storage stability is inferior.

<The shape of the inner wall surface when a via is formed>
A photosensitive film was formed on the copper-clad laminate by vacuum lamination of the photosensitive film. Thereafter, exposure / development was performed to form a 100 μm round hole pattern. The shape of the wall surface of the formed round hole pattern was observed by SEM.
〔Evaluation criteria〕
○: The wall surface is not uneven.
Δ: When slight irregularities are confirmed on the wall surface.
×: When unevenness is confirmed on the wall surface.

  From the result of Table 1, Examples 1-10 have the outstanding thermal cycle test tolerance and storage stability compared with Comparative Examples 1-3, and the shape of the inner wall surface when forming a via is smooth. I understood it.

The photosensitive composition of the present invention has excellent thermal cycle test resistance and storage stability, and since the shape of the inner wall surface when a via is formed is smooth, it can be suitably used for a solder resist for a package substrate. it can.
Since the photosensitive film of the present invention uses the photosensitive composition, various patterns such as a protective film, an interlayer insulating film, and a permanent pattern such as a solder resist pattern are formed, BGA (ball grid array), CSP (chip size package). ), For forming semiconductor packages such as TCP (tape carrier package), manufacturing of liquid crystal structural members such as color filters, pillars, ribs, spacers, partition walls, holograms, micromachines, proofs, etc. In particular, it can be suitably used for forming a permanent pattern of a printed circuit board, forming a semiconductor package such as a BGA (ball grid array), a CSP (chip size package), and a TCP (tape carrier package).
Since the pattern forming method of the present invention uses the photosensitive composition, it is used for forming semiconductor packages such as BGA (ball grid array), CSP (chip size package), and TCP (tape carrier package), a protective film, and an interlayer insulating film. And suitable for forming various patterns such as permanent patterns such as solder resist patterns, manufacturing of liquid crystal structural members such as color filters, pillar materials, rib materials, spacers, partition walls, holograms, micromachines, and proofs. In particular, it can be suitably used for forming a permanent pattern of a printed circuit board, forming a semiconductor package such as BGA (ball grid array), CSP (chip size package), TCP (tape carrier package).

Claims (9)

Including at least a binder, a polymerizable compound, and a filler,
The binder is a polymer compound having an acidic group and an ethylenically unsaturated bond in a side chain, and having any of a bisphenol A skeleton and a bisphenol F skeleton,
A photosensitive composition, wherein the filler is spherical silica surface-treated with a silane coupling agent.   The surface treatment is performed by coating silica with a silane coupling agent having at least one functional group selected from an alkoxysilyl group, a chlorosilyl group, and an acetoxysilyl group, and a (meth) acryloyl group. Photosensitive composition.   Furthermore, the photosensitive composition in any one of Claim 1 to 2 containing a thermal crosslinking agent.   The photosensitivity according to claim 3, wherein the thermal crosslinking agent is at least one selected from an epoxy resin, an oxetane resin, a bismaleimide resin, a cyanate resin, a benzocyclobutene resin, a bisallylnadiimide resin, and a benzoxazine resin. Composition.   Furthermore, the photosensitive composition in any one of Claim 1 to 4 containing an elastomer.   The photosensitive composition according to claim 5, wherein the elastomer is a polyester-based elastomer.   A photosensitive laminate comprising a photosensitive layer containing the photosensitive composition according to claim 1 on a substrate.   A method for forming a permanent pattern, comprising at least exposing a photosensitive layer formed of the photosensitive composition according to claim 1.   A printed circuit board, wherein a permanent pattern is formed by the permanent pattern forming method according to claim 8.