JP2003195486A - Photosensitive composition, cured product of the same and printed wiring board using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition to form a cured film having flexibility and satisfying both of the performance relating to the formation of a photosensitive coating film such as photosensitivity, developing properties and shelf life and the performance as an insulating protective coating film such as heat resistance, hardness and dimensional stability. <P>SOLUTION: The photosensitive composition comprises a compound (A) having an ethylenic unsaturated group, an epoxy resin (B), a photopolymerization initiator (C) and an interlayer compound (D) having at least one kind of a heat polymerization catalyst which is selected from the group consisting of amines, quaternary ammonium salts, acid anhydrides, polyamides, nitrogen- containing heterocyclic compounds and organic metal compounds and which is inserted into an inorganic layered compound. Since the composition contains the heat polymerization catalyst as the interlayer compound (D), the composition has excellent shelf life. Since the inorganic layered compound is dispersed in a nano order, the cured film shows excellent heat resistance and dimensional stability even when a large amount of the epoxy resin (B) is not used. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive composition used for an insulating protective coating for printed wiring boards and the like, and a cured product thereof.

[0002]

2. Description of the Related Art A protective film made of polyimide or polyester is widely used as an insulating protective film for wiring boards. When this protective film is provided on the wiring board, first, an adhesive is applied to one surface of the protective film.
Then, when this protective film is provided on the wiring board, only the portion corresponding to the terminal connection is punched by a method such as punching, the protective film is manually placed on the wiring board while being aligned, and the hot plate is pressed. Use under high temperature and high pressure to bond.

Polyimide, polyester, etc. are suitable for wiring protection because they have a certain degree of flexibility. However, in order to lead the wiring terminals on the wiring board, it is necessary to punch out the film and make holes in advance. Therefore, in recent years, an insulating protective film made of a photosensitive composition that does not require such mechanical processing has been developed.

As such a composition, for example, JP-A-57-55914 contains urethane di (meth) acrylate, a linear polymer compound having a specific glass transition temperature, and a sensitizer. A photosensitive resin composition for a dry film is disclosed. However, when a dry film made of this composition was used for a high-density printed wiring board, solder heat resistance and adhesion to the substrate were insufficient.

On the other hand, a photosensitive composition containing an epoxy resin has been investigated. For example, JP-A-49-10733
Japanese Patent Laid-Open Publication No. 1989-242242, a photosensitive composition comprising an unsaturated compound containing two terminal ethylene groups, a polymerization initiator, a compound containing at least two epoxy groups, and a compound containing at least two carboxyl groups. Is disclosed. Further, JP-A-61-272 discloses that a reaction product of a novolac type epoxy compound and an unsaturated monocarboxylic acid, a diisocyanate and a poly (meth) acrylate containing one hydroxyl group in one molecule. There is disclosed a composition containing an active energy ray-curable resin obtained by reacting with the reaction product of (1), and further containing a photopolymerization initiator, an organic solvent, and an epoxy resin.

However, since the photosensitive composition disclosed in JP-A-49-10733 is based on an acrylic linear polymer compound containing a (meth) acrylic group, it has low heat resistance and solvent resistance. . If the proportion of the epoxy resin is increased to solve such a drawback, the photocurability (photosensitivity) is lowered, and the resistance of the exposed portion to the developing solution is likely to be lowered. As a result, you can not develop for a long time,
In some cases, undeveloped areas may be left undeveloped. Also,
Regarding the composition disclosed in JP-A No. 61-272,
Increasing the proportion of epoxy resin causes similar problems.

Further, JP-A-61-243869 discloses a photosensitive resin obtained by reacting a reaction product of a novolac type epoxy compound and an unsaturated monocarboxylic acid with a saturated or unsaturated polybasic acid anhydride. And a composition further containing a photopolymerization initiator, a diluent and an epoxy resin. Since an alkaline aqueous solution is used for the development of this composition, if the ratio of the epoxy resin which is not soluble in the alkaline aqueous solution is increased, the photosensitivity is also lowered and the same problem as described above occurs. As described above, a composition having excellent properties such as solder heat resistance, adhesion to a substrate, and hardness, and also excellent photosensitivity has not been found.

On the other hand, when the photosensitive composition is used as an insulating protective film for a printed wiring board, it has excellent shelf life in addition to heat resistance, adhesion to a board, hardness, photosensitivity and the like. It is also required to be present. Further, the shrinkage during curing is small, and even when it is used for a thin wiring board such as a flexible printed wiring board (hereinafter, referred to as “FPC board”), the shrinkage during curing of the insulating protective film causes the FPC board to shrink. It is also desired that the phenomenon in which the warp is bent (hereinafter referred to as “warpage deformation”) does not occur and that the flexibility is excellent. As such a composition, Japanese Patent Publication No. 7-17737 discloses a photosensitive prepolymer having an ethylenically unsaturated bond, a photopolymerization initiator, a vinyl monomer as a diluent and an organic solvent, and a solid hardly soluble epoxy. Compositions based on resins are disclosed.

[0009]

However, the composition disclosed in Japanese Patent Publication No. 7-17737 has excellent flexibility, heat resistance, and shelf life, but has a large shrinkage ratio upon curing and a large warpage deformation. There was a problem. Also,
Conventionally, the photosensitive composition is made into a two-component type composed of a photo-curing component and a thermo-curing component, or a dry film is stored at a low temperature (4 ° C. or less) to take a measure to make the shelf life as long as possible. However, it was not at a satisfactory level. That is, photosensitivity and developability,
We have not found a material that has excellent shelf life, heat resistance, hardness, low warpage, etc. and that does not warp even when used for thin wiring boards such as FPC boards. It was

The present invention has been made in view of such circumstances, and has a performance related to the formation of a photosensitive coating such as photosensitivity, developability and shelf life, and an insulating protective coating such as heat resistance, hardness and dimensional stability. As well as the performance as
Moreover, it is an object to provide a photosensitive composition capable of forming a cured film having low warpage.

[0011]

The photosensitive composition of the present invention comprises a compound (A) having an ethylenically unsaturated group, an epoxy resin (B), a photopolymerization initiator (C), and an inorganic layered compound. And an intercalation compound (D) in which at least one thermal polymerization catalyst selected from the group consisting of amine, quaternary ammonium salt, acid anhydride, polyamide, nitrogen-containing heterocyclic compound, and organometallic compound is inserted. It is characterized by In addition, the method for curing the photosensitive composition of the present invention is such that the photosensitive composition is applied onto a substrate in a thickness of 10 to 100 μm and then dried in a temperature range of 60 ° C. to 100 ° C. for 5 minutes to 30 minutes. It is characterized in that it is heat-cured after exposure and development. The photosensitive dry film of the present invention is characterized by having a photosensitive layer formed from the above-mentioned photosensitive composition on a support. The method for producing the photosensitive dry film of the present invention is
The method is characterized by comprising a photosensitive layer forming step of coating the photosensitive composition on a support and drying. The insulating protective film of the present invention is characterized by comprising the above-mentioned photosensitive composition. The printed wiring board of the present invention is characterized by having the insulating protective film. The method for producing a printed wiring board of the present invention comprises a bonding step of bonding the photosensitive layer of the photosensitive dry film and the substrate, an exposure step of exposing the photosensitive layer, a developing step after the exposure step, and a photosensitive layer. And a heat-curing step of heat-curing.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The photosensitive composition of the present invention contains a compound (A) having an ethylenically unsaturated group as a photocurable component. The compound (A) having an ethylenically unsaturated group is not particularly limited, but at least one of an epoxy (meth) acrylate compound (A1) having a carboxyl group and a urethane (meth) acrylate compound (A2) having a carboxyl group. It is preferable to contain a seed. Epoxy (meth) acrylate compound (A1) having a carboxyl group
Has an action of improving the hardness and heat resistance of the cured film made of the photosensitive composition, and the urethane (meth) acrylate compound (A2) having a carboxyl group has an action of improving the flexibility of the cured film. Have.

In the photosensitive composition of the present invention, by adjusting the epoxy (meth) acrylate compound (A1) having a carboxyl group and the urethane (meth) acrylate compound (A2) having a carboxyl group at an arbitrary ratio, The hardness, heat resistance, flexibility, low warpage, etc. of the cured film can be arbitrarily controlled. For example, when forming a cured film having higher flexibility, a urethane (meth) acrylate compound (A2) having a carboxyl group is used, and an epoxy (meth) acrylate compound (A1) having a carboxyl group is used. You don't have to. In order to improve the flexibility, hardness, and heat resistance of the cured film, a carboxyl group-containing epoxy (meth) acrylate compound (A1) and a carboxyl group-containing urethane (meth) are used.
The ratio with the acrylate compound (A2) is 9: 1 to 1: 9.
(Mass ratio) is preferable.

Compound (A) having an ethylenically unsaturated group
Include these compounds (A1) and / or (A2)
Further, it is preferable to use at least one selected from the group consisting of a (meth) acrylate compound (A3) having a hydroxyl group, a glycidyl (meth) acrylate compound (A4) and a urethane acrylate (A5) in combination. When used together, the viscosity of the photosensitive composition,
It becomes easier to adjust physical properties such as photosensitivity and developability of the photosensitive composition. These are preferably contained in the range of 60% by mass or less in the compound (A) having an ethylenically unsaturated group. The range is more preferably 40% by mass or less.

Epoxy (meta) having carboxyl group
The acrylate compound (A1) can be obtained, for example, by reacting an epoxy compound with (meth) acrylic acid and an acid anhydride. The epoxy compound used here is not particularly limited, but includes a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a bisphenol S type epoxy compound, a phenol novolac type epoxy compound, a cresol novolac type epoxy compound, or Epoxy compounds such as aliphatic epoxy compounds may be mentioned. As the acid anhydride, maleic anhydride, succinic anhydride, itaconic anhydride,
Dibasic acid such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, chlorendic anhydride, methyltetrahydrophthalic anhydride Aromatic polyhydric carboxylic acid anhydrides such as acid anhydrides, trimellitic anhydride, pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, 5- (2,5-dioxotetrahydrofuryl) -3-methyl- 3-cyclohexene-1,2-
Dicarboxylic acid anhydride, endobicyclo- [2,2,1]
-Hept-5-ene-2,3-dicarboxylic acid anhydride and the like.

The solid acid value of the epoxy (meth) acrylate compound (A1) having a carboxyl group is
It is preferably 10 mgKOH / g or more and 160 mgKOH / g or less, and preferably 45 to 160 mgKOH.
/ G, more preferably 50-140 mg KOH / g
Is. Here, the solid content acid value is the net acid value of the epoxy (meth) acrylate compound (A1) having a carboxyl group. When the epoxy (meth) acrylate compound (A1) having such a solid content acid value is used, the balance between the alkali solubility of the photosensitive composition and the alkali resistance of the cured film can be improved. Solid content acid value 10 mg
When it is less than KOH / g, the alkali solubility is deteriorated and the developability is deteriorated. On the other hand, if it is too large, the characteristics as a resist such as the alkali resistance of the cured film and the electrical characteristics may deteriorate depending on the constituent components of the photosensitive composition.

Urethane (meth) having a carboxyl group
As an example of the acrylate compound (A2), a compound containing a unit derived from a (meth) acrylate (a) having a hydroxyl group, a unit derived from a polyol (b), and a unit derived from a polyisocyanate (c) as constituent units. Is mentioned. In this compound, both ends are composed of a unit derived from (meth) acrylate (a) having a hydroxyl group, and a unit derived from a polyol (b) and a polyisocyanate (c) which are linked by a urethane bond between the both ends. And units. And, some of the repeating units linked by the urethane bond have a structure in which a carboxyl group is present.

That is, the urethane (meth) acrylate compound (A2) having a carboxyl group is-(ORb
O-CONHRcNHCO) n- [In the formula, ORbO represents a dehydrogenation residue of the polyol (b), and Rc represents a deisocyanate residue of the polyisocyanate (c). ] Is represented.
The urethane (meth) acrylate compound (A2) having a carboxyl group includes at least a hydroxyl group-containing (meth) acrylate (a) and a polyol (b).
And a polyisocyanate (c) are reacted with each other, but it is necessary to use a compound having a carboxyl group in at least one of the polyol (b) and the polyisocyanate (c). Is. Preferably, the polyol (b) having a carboxyl group is used. Thus, by using a compound having a carboxyl group as the polyol (b) and / or the polyisocyanate (c), a urethane (meth) acrylate compound (A2) having a carboxyl group in Rb or Rc is produced. it can. In the above formula, n
Is preferably about 1 to 200, more preferably 2 to 30. When n is in such a range, the flexibility of the cured film made of the photosensitive composition is more excellent. When two or more kinds of at least one of the polyol (b) and the polyisocyanate (c) are used, the repeating unit represents a plurality of kinds, but the regularity of the plurality of units is completely random or block. , Localization, etc. can be appropriately selected according to the purpose.

Examples of the (meth) acrylate (a) having a hydroxyl group used here include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and each of the above (meth) acrylates. Caprolactone or alkylene oxide adduct, glycerin mono (meth) acrylate, glycerin di (meth) acrylate, glycidyl methacrylate-acrylic acid adduct, trimethylolpropane mono (meth) acrylate, trimethylol di (meth) acrylate, pentaerythritol tri- (Meth) acrylate, dipentaerythritol penta (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, trimethylolpropane-alkylene oxide addition - di (meth) acrylate. These (meth) acrylates (a) having a hydroxyl group can be used alone or in combination of two or more. Among these, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate are preferable, and 2-hydroxyethyl (meth) acrylate is preferable.
Acrylate is more preferred. When 2-hydroxyethyl (meth) acrylate is used, the urethane (meth) acrylate compound (A2) having a carboxyl group can be easily synthesized.

The polyol (b) is a compound which, together with the polyisocyanate (c), constitutes a repeating unit of the urethane (meth) acrylate compound (A) having a carboxyl group. As the polyol (b), a polymer polyol (b1) and / or a dihydroxyl compound (b2) can be used.

The polymer polyol (b used here
1) Polyether diol such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyester polyol obtained from ester of polyhydric alcohol and polybasic acid, polycarbonate diol such as hexamethylene carbonate, pentamethylene carbonate, etc. , Polycaprolactone diol, polybutyrolactone diol, and other polylactone-based diols. When the polymer polyol (b1) having a carboxyl group is used, for example, when the polymer polyol (b1) is synthesized,
A compound obtained by allowing a carboxyl group to remain by coexisting with a tribasic or more polybasic acid such as (anhydrous) trimellitic acid can be used. The polymer polyol (b1) can be used alone or in combination of two or more. The number average molecular weight of these polymer polyols (b1) is 200 to 20.
It is preferable to use the compound of No. 00 because the cured film made of the photosensitive composition has more excellent flexibility.

As the dihydroxyl compound (b2),
A branched or linear compound having two alcoholic hydroxyl groups can be used, but it is particularly preferable to use a dihydroxy aliphatic carboxylic acid having a carboxyl group. Examples of such a dihydroxyl compound (b2) include dimethylolpropionic acid and dimethylolbutanoic acid. By using a dihydroxy aliphatic carboxylic acid having a carboxyl group, the carboxyl group can be easily present in the urethane (meth) acrylate compound (A2). The dihydroxyl compound (b2) can be used alone or in combination of two or more, and may be used together with the polymer polyol (b1). Moreover, when using together the polymer polyol (b1) which has a carboxyl group, or when using what has a carboxyl group as the polyisocyanate (c) mentioned later, ethylene glycol, diethylene glycol, propylene glycol, 1,4- Butanediol, 1,3-butanediol, 1,5-pentanediol, neopentyl glycol, 3-methyl-1,
5-pentanediol, 1,6-hexanediol,
A dihydroxyl compound (b2) having no carboxyl group such as 1,4-cyclohexanedimethanol or hydroquinone may be used.

Specific examples of the polyisocyanate (c) used in the present invention include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and diphenyl. Methylene diisocyanate, (o, m,
Or p) -xylene diisocyanate, methylenebis (cyclohexyl isocyanate), trimethylhexamethylene diisocyanate, cyclohexane-1,3-
Dimethylene diisocyanate, cyclohexane-1,4
-Dimethylate diisocyanates and diisocyanates such as 1,5-naphthalene diisocyanate. These polyisocyanates can be used alone or in combination of two or more.

The urethane (meth) acrylate compound (A2) having a carboxyl group used in the present invention preferably has a number average molecular weight of 1,000 to 40,000 and a solid content acid value of 5 to 150 mgKOH / g. Here, the number average molecular weight is a polystyrene equivalent value measured by gel permeation chromatography. If the number average molecular weight of the urethane (meth) acrylate compound (A2) having a carboxyl group is less than 1000, the elongation and strength of the cured film made of the photosensitive composition may be impaired, and if it exceeds 40,000, the film becomes hard but flexible. There is a risk that it will deteriorate the sex. In addition, the solid content acid value is 5 mgKOH / g
If it is less than 150 mgKOH / g, the alkali solubility of the photosensitive composition may be deteriorated. If it exceeds 150 mgKOH / g, the cured film may have poor alkali resistance and electric characteristics. The solid acid value is the net acid value of the urethane (meth) acrylate compound (A2) having a carboxyl group.

Urethane (meth) having a carboxyl group
The acrylate compound (A2) is obtained by (1) a method in which the (meth) acrylate (a) having a hydroxyl group, the polyol (b), and the polyisocyanate (c) are collectively mixed and reacted, and (2) the polyol (b). ) And polyisocyanate (c) to produce a urethane isocyanate prepolymer containing one or more isocyanate groups per molecule, and then the urethane isocyanate prepolymer and a hydroxyl group (meth) Method of reacting acrylate (a), (3) Urethane isocyanate containing one or more isocyanate groups per molecule by reacting (meth) acrylate (a) having a hydroxyl group with polyisocyanate (c) A method of reacting the prepolymer with the polyol (b) after producing the nato prepolymer It can be produced, and the like.

Epoxy (meth) having a carboxyl group
As the (meth) acrylate compound (A3) having a hydroxyl group, which is used in combination with at least one kind of the acrylate compound (A1) or the urethane (meth) acrylate compound (A2) having a carboxyl group, 2-hydroxyethyl (meth) acrylate, Examples thereof include hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, ω-hydroxyhexanoyloxyethyl (meth) acrylate, and 2-hydroxy-3-phenoxypropyl acrylate. Moreover, you may use together a glycidyl (meth) acrylate compound (A4) and urethane acrylate (A5).

Compound (A) having an ethylenically unsaturated group
In addition, a low molecular weight (meth) acrylate or the like can be used. As low molecular weight (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate
Acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-
Butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, etc. Alkyl (meth) acrylate of cyclohexyl (meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, etc. Acrylate; benzyl (meth) acrylate, phenyl (meth) acrylate, phenyl carbitol (meth)
Acrylate, nonylphenyl (meth) acrylate,
Aromatic (meth) acrylates such as nonylphenyl carbitol (meth) acrylate and nonylphenoxy (meth) acrylate; 2-dimethylaminoethyl (meth)
Acrylate, 2-diethylaminoethyl (meth) acrylate, 2-tert-butylaminoethyl (meth)
(Meth) acrylate having amino group such as acrylate; methacryloxyethyl phosphate, bis-methacryloxyethyl phosphate, methacrylooxyethyl phenyl acid phosphate (phenyl P)
Methacrylates having phosphorus atoms such as ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol Di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,4-
Butanediol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, bis-glycidyl (meth) acrylate, etc. Diacrylates; polyacrylates such as trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate;
Bisphenol S ethylene oxide 4 mol modified diacrylate, bisphenol A ethylene oxide 4 mol modified diacrylate, fatty acid modified pentaerythritol diacrylate, trimethylol propane 3 mol modified triacrylate, trimethylol propane 6 mol modified triacrylate Polyacrylates having an isocyanuric acid skeleton such as bis (acryloyloxyethyl) monohydroxyethyl isocyanurate, tris (acryloyloxyethyl) isocyanurate, and ε-caprolactone modified tris (acryloyloxyethyl) isocyanurate; α, ω-diacryloyl- (bisethylene glycol) -phthalate, α,
Polyester acrylates such as ω-tetraacryloyl- (bistrimethylolpropane) -tetrahydrophthalate; allyl (meth) acrylate; polycaprolactone (meth) acrylate; (meth) acryloyloxyethyl phthalate; (meth) acryloyloxyethyl succinate; phenoxyethyl Acrylate etc. are mentioned. Further, N-vinyl compounds such as N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, epoxy acrylate and the like can also be used.

The epoxy resin (B) used in the photosensitive composition of the present invention is contained in the photosensitive composition as a thermosetting component, and is a bisphenol A type epoxy resin,
Hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, N-glycidyl type epoxy resin, bisphenol A
Novolak type epoxy resin, chelate type epoxy resin, glyoxal type epoxy resin, amino group containing epoxy resin, rubber modified epoxy resin, dicyclopentadiene phenolic type epoxy resin, silicone modified epoxy resin, ε-caprolactone modified epoxy resin, etc. Examples thereof include epoxy compounds having two or more epoxy groups. Further, in order to impart flame retardancy, it is also possible to use one in which an atom such as halogen such as chlorine and bromine or an atom such as phosphorus is introduced into the structure in a bonded state that is not easily decomposed by heat or water. Further, a bisphenol S type epoxy resin, a diglycidyl phthalate resin, a heterocyclic epoxy resin, a bixylenol type epoxy resin, a biphenyl type epoxy resin, a tetraglycidyl xylenoyl ethane resin or the like may be used. These epoxy resins are
One kind or a combination of two or more kinds can be used.

The photosensitive composition of the present invention may be a heterogeneous system containing a dispersed phase composed of an epoxy resin (B). Specifically, there is a state in which a solid or semi-solid type epoxy resin (B) is recognized in the photosensitive composition before curing, and the epoxy resin (B) is contained in the photosensitive composition. It is in a state of non-uniform mixing. For example, it is also included that the entire photosensitive composition before curing is not uniformly transparent and at least a part thereof is opaque. As described above, when the photosensitive composition before curing is a heterogeneous system containing a dispersed phase composed of the epoxy resin (B), the shelf life of the photosensitive composition may be long.

In the photosensitive composition of the present invention, the compounding amount of the epoxy resin (B) which is a thermosetting component is 1 with respect to 100 parts by mass of the compound (A) having an ethylenically unsaturated group.
0 to 150 parts by mass is preferable, and more preferably 20 to 5 parts.
It is 0 part by mass. When the blending amount of the epoxy resin (B) is less than 10 parts by mass, the solder heat resistance of the cured film made of the photosensitive composition may be insufficient. On the other hand, when it exceeds 150 parts by mass, the amount of shrinkage of the cured film increases, and when the cured film is used as the insulating protective film of the FPC substrate, warp deformation tends to increase.

As the photopolymerization initiator (C) used in the present invention, benzophenone, benzoylbenzoic acid, 4-phenylbenzophenone, hydroxybenzophenone,
Benzophenones such as 4,4′-bis (diethylamino) benzophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, benzoin alkyl ethers such as benzoin isobutyl ether, 4-phenoxydichloroacetophenone, 2- Hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, 1- [4- (2-hydroxyethoxy) phenyl]- 2-hydroxy di-
2-methyl-1-propan-1-one, 1-hydroxy-cyclohexyl-phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-diethoxy-1,2-diphenylethane On, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1,4-t-butyl-dichloroacetophenone, 4-t-butyl-trichloroacetophenone, diethoxyacetophenone, 2- Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,1-phenyl-1,2-propanedione-
Acetophenones such as 2- (o-ethoxyarbonyl) oxime, thioxanthenes such as thioxanthene, 2-chlorothioxanthene, 2-methylthioxanthene and 2,4-dimethylthioxanthene, alkyls such as ethylanthraquinone and butylanthraquinone Examples thereof include anthraquinones and acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide. These can be used alone or as a mixture of two or more kinds.

As the photopolymerization initiator (C), 2,
2,2-Trichloro- [1-4 '-(1,1-dimethylethyl) phenyl] ethanone, 2,2-dichloro-1-
4 '-(phenoxyphenyl) ethanone, α, α, α-
Tribromomethylphenyl sulfone, 2,4,6-tris (trichloromethyl) triazine, 2,4-trichloromethyl- (4'-methoxystyryl) -6-triazine, 2,4-trichloromethyl- (pipronyl) -6
-Triazine, 2,4-trichloromethyl- (4'-methoxynaphthyl) -6-triazine, 2 [2 '(5''
-Methylfuryl) ethylidene-4,6-bis (trichloromethyl) -S-triazine, 2 (2'-furyl) ethylidene] -4,6-bis (trichloromethyl) -S-triazine and other photoacid generators are also included. Can be used. Further, if necessary, a photosensitizer can be used in combination.

Of these photopolymerization initiators (C), benzophenones, acetophenones, and acylphosphine oxides are preferable, and specific examples include 4,
4'-bis (diethylamino) benzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2,4,6-trimethylbenzoyldiphenylphosphine oxide can be mentioned. The compounding amount of these photopolymerization initiators (C) is such that the compound (A) 10 having an ethylenically unsaturated group as a photocuring component is used.
0.1 to 20 parts by mass is preferable with respect to 0 parts by mass,
0.2 to 10 parts by mass is more preferable. When the blending amount of the photopolymerization initiator (C) is less than 0.1 part by mass, curing of the photosensitive composition may be insufficient.

The photosensitive composition of the present invention further contains an intercalation compound (D) in which a thermal polymerization catalyst is inserted into an inorganic layered compound. Here, the intercalation compound (D) is an inorganic layered compound, that is, a layered clay mineral such as a layered silicate that is a cation-exchangeable layered compound, a hydrotalcite compound that is an anion-exchanged layered compound, or a derivative thereof. Between layers such as compounds, a thermal polymerization catalyst is inserted, which will be described in detail later, for example, by substituting all or part of the anions and cations of these inorganic layered compounds with the thermal polymerization catalyst. Is what you get.
By using layered clay minerals such as layered silicates that are cation-exchangeable layered compounds, hydrotalcites that are anion-exchanged layered compounds, and compounds derived from these, thermal polymerization between these layers is relatively easy. A catalyst can be inserted, which is preferable. In addition, as the intercalation compound (D), titanate, niobium oxide, graphite or the like having a thermal polymerization catalyst inserted between the layers can be used.

Examples of the layered silicate include smectite clay minerals such as montmorillonite, saponite, beidellite, hectorite, nontronite and stevensite; vermiculites such as trioctahedral vermiculite and dioctahedral vermiculite;
Examples include mica such as mascobite, phlogobite, biotite, lepidrite, baragonite, teniolite, and tetrasilicon mica.

Further, in the present invention, "hydrotal
"Sites" means hydrotalcite and the same crystals
It is a generic term for hydrotalcites having a structure,
These are included. That is, hydrotarsai
Is originally a natural mineral, Mg₆Al₂(OH) ₁₆CO
₃・ 4-5H₂Although it is the name given to O,
It has the same crystal structure and has the following formulas (i) and (ii)
Many minerals shown in were discovered and synthesized. At present
Is usually M²⁺Is Mg and M³⁺Is A
The compound with l is called hydrotalcite,
The compounds represented by the following formulas (i) and (ii) are high
They are called dorotalcites.

[M ²⁺ _1-x M ³⁺ _x (OH) ₂ ] ^{x +} [anion] ^x -... (i) [M ³⁺ ₂ (OH) ₆ M ¹⁺ _x ] ^{y +} [anion] ^{y -} ··· (ii) where, 0.1 ≦ x ≦ 0.4,0 <y <2, M 1+ is L
i, Na, K, Rb, at least one monovalent metal represented by Cs, M ²⁺ is Mg, Ca, Mn, Fe,
At least one divalent metal typified by Co, Ni, Cu, Zn, etc., and M ³⁺ is at least one trivalent metal typified by Al, Fe, Cr, In, [anion].
^x- and [anion] ^x- are hydrated anions or organic anions existing between crystal layers.

The structural units of these hydrotalcites are composed of a positively charged basic layer and an intermediate layer having an anion for neutralizing the positive potential and water of crystallization. It is known that these hydrotalcites show almost similar properties except that they have different structural destruction temperatures. Regarding these compounds, "Smectite Study Group Bulletin" Smectite "" (Vol. 6, No. 1)
No. 12-26, May 1996). As specific examples of hydrotalcites,
Examples include Stigite, Pyro-aurite, Levesite, Tacovite, Onesite, and Iowite.

In the case of hydrotalcites having a hydrated anion between crystal layers, in the above formulas (i) and (ii),
[Anion] ^x- and [anion] ^y- are [A ^n- _{x / n} · mH
₂ O] ^{x −} and [A ⁿ⁻ _{x / n} · mH ₂ O] ^{y −} are hydrated anions. Therefore, the general formula of the hydrotalcite compound having a hydrated anion between the crystal layers is represented by the following formulas (iii) and (iv). Here, A ⁿ⁻ is Cl ⁻ , Br ⁻ , CO ₃ ²⁻ , NO ₃ ²⁻ , SO ₄
^2- , Fe (CN) ₆ ^4- , and at least one of n-valent ion-exchange anions represented by tartrate ions.

[M ²⁺ _1-x M ³⁺ _x (OH) ₂ ] ^{x +} [A ^n- _{x / n} · mH ₂ O] ^x -... (iii) [M ³⁺ ₂ (OH) ₆ M ¹⁺ _x ] ^{y +} [A ^n- _{x / n} · mH ₂ O] ^{y -...} (iv) where 0.1 ≦ x ≦ 0.4, 0 <y <2, and m is an integer of 1 or more. , N is an integer of 1 to 4. M ¹⁺ , M ²⁺ , M ³⁺
Has the same meaning as in formulas (i) and (ii).

In the case of hydrotalcites having an organic anion between crystal layers, the organic anion is not particularly limited, but amino acids, sulfur-containing compounds, nitrogen-containing heterocyclic compounds and their salt compounds are preferable. Specifically, leucine, cystine, phenylalanine, tyrosine, aspartic acid, glutamic acid, lysine, 6-aminohexylcarboxylic acid, 12-aminolaurylcarboxylic acid,
N, N-dimethyl-6-aminohexylcarboxylic acid, N
-N-dodecyl-N, N-dimethyl 10-aminodecylcarboxylic acid, dimethyl-N-12 aminolaurylcarboxylic acid and other amino acid derivatives, 2-chlorobenzthiazole, thioacetic acid, methyldithiocarbamic acid,
Sulfur-containing compounds such as dimethyldithianoalbamate and salts thereof, 2-mercaptothiazoline, 2,5-dimercapto-1,3,4thiadiazole, 1-carboxymethyl-5-mercapto 1H-tetrazole, 2,
Examples thereof include nitrogen-containing heterocyclic compounds such as 4,6-trimercapto-s-triazine and salt compounds thereof.

The hydrotalcites having an organic anion between these crystal layers do not exist in nature and can be obtained by treating the hydrotalcites with an organic solvent containing a predetermined organic anion. In this way, hydrotalcites having an organic anion are preliminarily synthesized between the crystal layers, and then a thermal polymerization catalyst is inserted between the layers to obtain the intercalation compound (D). Here, when the thermal polymerization catalyst is inserted after the organic anion is present in advance between the crystal layers, the affinity between the hydrotalcites and the thermal polymerization catalyst is increased due to the presence of the organic anion, and the thermal polymerization catalyst is easily provided between the crystal layers. Can be inserted, which is preferable.

The thermal polymerization catalyst inserted into the inorganic layered compound has a function of thermally curing the epoxy resin (B), and includes amines, quaternary ammonium salts, cycloaliphatic acid anhydrides, and aliphatic acid anhydrides. And acid anhydrides such as aromatic acid anhydrides,
At least one selected from the group consisting of polyamides, imidazoles, nitrogen-containing heterocyclic compounds such as triazine compounds, and organometallic compounds is used.

Examples of amines include aliphatic and aromatic primary, secondary and tertiary amines. Examples of aliphatic amines are polymethylenediamine, polyetherdiamine, diethylenetriamine, triethylenetriamine,
Tetraethylenepentamine, triethylenetetramine,
Dimethylaminopropylamine, Mensendiamine, Aminoethylethanolamine, Bis (hexamethylene)
Triamine, 1,3,6-trisaminomethylhexane, tributylamine, 1,4-diazabicyclo [2,2]
2,2] octane, 1,8-diazabicyclo [5,4,4]
0] Undecen-7-ene and the like. Examples of aromatic amines include metaphenylenediamine, diaminodiphenylmethane, diaminodiphonylmethane, diaminodiphenylsulfone, benzyldimethyldiamine and the like.

Examples of the quaternary ammonium salt include tetrabutylammonium ion, tetrahexylammonium ion, dihexyldimethylammonium ion, dioctyldimethylammonium ion, hexatrimethylammonium ion, octatrimethylammonium ion, dodecyltrimethylammonium ion, hexadecyltrimethylammonium ion. , Stearyl trimethyl ammonium ion, docosenyl trimethyl ammonium ion, cetyl trimethyl ammonium ion,
Cetyltriethylammonium ion, hexadecylammonium ion, tetradecyldimethylbenzylammonium ion, stearyldimethylbenzylammonium ion, dioleyldimethylammonium ion,
N-methyldiethanol lauryl ammonium ion,
Examples thereof include quaternary ammonium salts provided with dipropanol monomethyllauryl ammonium ion, dimethylmonoethanol lauryl ammonium ion, polyoxyethylene dodecylmonomethylammonium ion, and alkylaminopropylamine quaternary compounds.

As the acid anhydride, phthalic anhydride, trimellitic anhydride, benzophenonetetracarboxylic acid anhydride,
Aromatic acid anhydrides such as ethylene glycol bis (anhydro trimellitate) and glycerol tris (anhydro trimellitate), maleic anhydride, succinic anhydride, methyl nadic acid anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride , Polyadipic anhydride, chlorendic anhydride, tetrabromophthalic anhydride and the like. Examples of polyamides include polyaminoamides having primary and secondary amino groups, which are obtained by subjecting dimer acid to a condensation reaction of polyamines such as diethylenetriamine and triethylenetetraamine.

Specific examples of the imidazoles include imidazole, 2-ethyl-4-methylimidazole, N
-Benzyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate,
2-Methylimidazolium / isocyanurate and the like can be mentioned.

The triazine compound is a compound having a 6-membered ring containing 3 nitrogen atoms, and examples thereof include a melamine compound, a cyanuric acid compound and a cyanuric acid melamine compound. Specific examples of the melamine compound include melamine, N-ethylenemelamine, N, N ′, N ″ -triphenylmelamine and the like. Examples of the cyanuric acid compound include cyanuric acid, isocyanuric acid, trimethylcyanurate, trismethylisocyanurate, triethylcyanurate, trisethylisocyanurate, tri (n-propyl) cyanurate, tris (n-propyl) isocyanurate, diethylcyanurate. , N,
N'-diethyl isocyanurate, methyl cyanurate, methyl isocyanurate, etc. are mentioned. Examples of the melamine cyanurate compound include equimolar reaction products of a melamine compound and a cyanuric acid compound.

As the organic metal compound, an organic acid metal salt,
Examples thereof include 1,3-diketone metal complex salts and metal alkoxides. Specifically, organic acid metal salts such as dibutyltin dilaurate, dibutyltin maleate and zinc 2-ethylhexanoate, 1,3-diketone metal complex salts such as nickel acetylacetonate and zinc acetylacetonate, titanium tetrabutoxide and zirconium. Examples thereof include metal alkoxides such as tetrabutoxide and aluminum butoxide.

In the present invention, the above-exemplified inorganic layered compound and the thermal polymerization catalyst are appropriately mixed, stirred, and optionally heat-treated so that the thermal polymerization catalyst is inserted between the layers of the inorganic layered compound. It can be used as an intercalation compound (D), but in particular, as a layered silicate or hydrotalcite such as smectite clay mineral, vermiculite or mica is used as an inorganic layered compound, metal ions existing between the layers An intercalation compound (D) obtained by ion exchange with ions derived from a thermal polymerization catalyst is preferable. As the thermal polymerization catalyst used in this case, amines, quaternary ammonium salts, imidazoles, and triazine compounds are particularly preferable because they can easily generate cations and exchange with the metal ions between the layers of the layered silicate.

For ion exchange, first, the layered silicate or hydrotalcite is dispersed in water or alcohol, and then a thermal polymerization catalyst is added to this suspension and stirred,
Ions between the layers of the layered silicate or hydrotalcite are replaced with cations or anions derived from the thermal polymerization catalyst. Then, washing and filtration are repeated to remove the free thermal polymerization catalyst and drying, whereby the intercalation compound (D) having the thermal polymerization catalyst inserted between the layers can be produced. Also,
When the affinity between the layered silicate or hydrotalcite used and the thermal polymerization catalyst is low, other organic cations having a high affinity with the layered silicate, as described in the explanation of hydrotalcites, for example. Alternatively, an ion between the ionic layers is replaced with an ion such as an organic anion to once prepare an intercalation compound having a high affinity with the thermal polymerization catalyst, and then the thermal polymerization catalyst is further inserted into this intercalation compound to form a desired intercalation layer. A thermal polymerization catalyst may be present.

The content of the thermal polymerization catalyst in the intercalation compound (D) is preferably 5 to 50% by mass, more preferably 10 to 30% by mass. If it is less than 5% by mass, heat resistance may be deteriorated due to insufficient curing,
When it exceeds 50% by mass, the storage capacity between the layers is exceeded, so that excellent shelf life may not be exhibited.

Such an intercalation compound (D) is dispersed in the photosensitive composition of the present invention in a state where a thermal polymerization catalyst is held between the layers of the inorganic stratiform compound. Therefore, in this photosensitive composition, free contact between the epoxy resin (B) and the thermal polymerization catalyst is suppressed, and the curing of the epoxy resin (B) due to the action of the thermal polymerization catalyst is suppressed. Therefore, by blending and dispersing the thermal polymerization catalyst in the form of the intercalation compound (D) in the photosensitive composition, the shelf life of the photosensitive composition can be improved, and the thermal composition of the photosensitive composition can be improved. It is possible to suppress the progress of curing during storage or transportation. When the photosensitive composition is heated to cure it, a thermosetting reaction starts in the vicinity of the interlayer thermal polymerization catalyst of the intercalation compound (D). Then, as the thermosetting reaction proceeds, the distance between the bottom surfaces of the intercalation compound (D) is 2.5 to
It becomes large up to about 3.0 nm, and each layer begins to peel. As a result, each layer in the photosensitive composition is in a state of being finely dispersed at a nanometer level, that is, a so-called nano-dispersed state. The nano-dispersed layered compound improves not only the heat resistance of the cured product of the photosensitive composition but also the dimensional stability. Therefore, when a cured film is formed using this photosensitive composition, the shrinkage amount at the time of curing is reduced, and warp deformation is suppressed even when this is used for an insulating protective film of an FPC substrate. The photosensitive composition containing the interlayer composition (D) having a thermal polymerization catalyst between the layers as described above has excellent shelf life, and also has excellent heat resistance and dimensional stability of the cured film, and is used as an insulating protective film. Will be suitable for.

The intercalation compound (D) is 1 to 20% by mass in the photosensitive composition excluding components such as organic solvents that volatilize after coating.
It is preferably contained, and more preferably 2 to 10% by mass. If it is less than 1% by mass, the thermosetting property becomes insufficient, and the heat resistance of the insulating protective film may become insufficient.
When it exceeds 0% by mass, the amount of the inorganic layered compound increases, so that the flexibility may deteriorate.

The photosensitive composition of the present invention can be produced by mixing the above-mentioned components by a conventional method. The mixing method is not particularly limited, and some components may be mixed and then the remaining components may be mixed, or all the components may be mixed at once. Further, an organic solvent may be added to the photosensitive composition, if necessary, in order to adjust the viscosity. By adjusting the viscosity in this way, it becomes easy to apply or print on an object by roller coating, spin coating, screen coating, curtain coating, or the like. Examples of the organic solvent include ketone solvents such as ethyl methyl ketone, methyl isobutyl ketone and cyclohexanone; ester solvents such as ethyl acetoacetate, γ-butyrolactone and butyl acetate; butanol;
Alcohol-based solvents such as benzyl alcohol; Cellosolve-based, carbitol-based and their ester and ether derivative solvents; N, N-dimethylformamide, N, N
-Amide solvents such as dimethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone; dimethyl sulfoxide; phenol solvents such as phenol and cresol; nitro compound solvents; toluene, xylene, hexamethylbenzene, cumene Aromatic solvents; aromatic solvents such as tetralin, decalin, dipentene and other hydrocarbons, alicyclic solvents, and the like. One kind or a combination of two or more kinds can be used.

The amount of the organic solvent used is such that the viscosity of the photosensitive composition is 500 to 500,000 mPa · s [B type viscometer (Bro
okfield Viscometer) at 25 ℃. ] It is preferable to adjust so that. More preferably 1,000 to 5
It is 0,000 mPa · s. With such a viscosity, it is more suitable for application and printing on an object and is easy to use. The amount of the organic solvent used to obtain such a viscosity is 1.5 times or less the mass of the solid content other than the organic solvent. If it exceeds 1.5 times by mass, the solid content concentration will be low, and when printing this photosensitive composition on a substrate or the like, a sufficient film thickness cannot be obtained by one printing, and multiple printing is required. There are cases.

A flow control agent may be further added to the photosensitive composition of the present invention in order to control the flowability. The fluidity adjusting agent is preferable because it can appropriately adjust the fluidity of the photosensitive composition, for example, when the photosensitive composition is applied to an object by roller coating, spin coating, screen coating, curtain coating, or the like. Examples of flow regulators include inorganic and organic fillers, waxes, surfactants and the like. Specific examples of the inorganic filler include talc,
Barium sulfate, barium titanate, silica, alumina,
Examples thereof include clay, magnesium carbonate, calcium carbonate, aluminum hydroxide and silicate compounds. Specific examples of the organic filler include silicone resin, silicone rubber, and fluorine resin. Specific examples of the wax include polyamide wax and oxidized polyethylene wax. Specific examples of the surfactant include silicone oil,
Examples include higher fatty acid esters and amides. These fluidity modifiers may be used alone or in combination of two or more. Further, among these, when an inorganic filler is used, not only the fluidity of the photosensitive composition,
It is preferable because properties such as adhesion and hardness can be improved.

If necessary, the photosensitive composition may include a colorant, a thermal polymerization inhibitor, a thickener, a defoaming agent, a leveling agent,
Additives such as adhesion promoters can be added. Examples of the colorant include phthalocyanine blue, phthalocyanine green, iodin green, disazo yellow, crystal violet, titanium oxide, carbon black and naphthalene black. Examples of the thermal polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol, phenothiazine and the like. As a thickener,
Examples thereof include layered silicates such as hectorite, montmorillonite, saponite, hydelite, stevensite, tetrasilicon mica, and teniolite, and intercalation compounds obtained by treating them with an organic cation, silica and organized silica. The defoaming agent is used to eliminate bubbles generated during printing, coating and curing, and specific examples thereof include acrylic and silicone type surfactants. The leveling agent is
It is used to eliminate the irregularities on the surface of the film that occur during printing and coating, and specific examples thereof include acrylic and silicone surfactants. Examples of the adhesion-imparting agent include imidazole-based, thiazole-based, triazole-based and silane coupling agents. In addition, as other additives, for example, an ultraviolet protective agent, a plasticizer, etc. for storage stability,
It can be added within a range that does not impair the gist of the present invention.

The photosensitive composition of the present invention is applied on a substrate or the like in an appropriate thickness, heat-treated and dried, and then exposed,
A cured product can be obtained by developing and thermosetting to cure. The photosensitive composition of the present invention can be used in various applications, but has heat resistance, hardness, dimensional stability, flexibility, and can form a cured film that is unlikely to warp,
It is suitable for use as an insulating protective film for printed wiring boards, and particularly suitable for insulating protective films for FPC boards. In the case of forming an insulating protective film, the photosensitive composition is applied on the substrate on which the circuit is formed in a thickness of 10 μm to 100 μm, and then, in a temperature range of 60 ° C. to 100 ° C.
Heat treatment for about 30 minutes to dry, then expose through a negative mask having a desired exposure pattern, remove the unexposed portion with a developer and develop, 100 ° C to 180 ° C
In this temperature range, a method of heat curing for about 20 to 60 minutes may be used. In addition, the photosensitive composition of the present invention,
For example, it may be used as an insulating resin layer between layers of a multilayer printed wiring board.

As the active light used for the exposure, active light generated from a known active light source, for example, carbon arc, mercury vapor arc, xenon arc or the like is used. Since the sensitivity of the photopolymerization initiator (C) contained in the photosensitive layer is usually the maximum in the ultraviolet region, in that case, it is preferable that the active light source emits ultraviolet light effectively. Of course, those in which the photopolymerization initiator (C) is sensitive to visible light, for example,
In the case of 9,10-phenanthrenequinone or the like, visible light is used as the active light, and a photographic flood light bulb, a sun lamp, or the like is used as the light source in addition to the active light source. The developer can be selected according to the type of the compound (A) having an ethylenically unsaturated group to be used. For example, when a compound having a carboxyl group is used, potassium hydroxide, sodium hydroxide, An alkaline aqueous solution of sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, amines or the like can be used.

The photosensitive composition of the present invention can also be used in the photosensitive layer of a photosensitive dry film. The photosensitive dry film has a photosensitive layer made of a photosensitive composition on a support made of a polymer film or the like. Examples of the polymer film used for the support include, for example, polyethylene terephthalate, polyester resins such as aliphatic polyester, polypropylene, and films made of polyolefin resin such as low-density polyethylene. A film made of polyethylene is preferred. Further, since these polymer films need to be removed from the photosensitive layer later, it is preferable that they can be easily removed from the photosensitive layer. The thickness of these polymer films is usually 5-100.
μm, preferably 10 to 30 μm.

The photosensitive dry film can be produced by a photosensitive layer forming step of coating a photosensitive composition on a support and drying it. Further, by providing a cover film on the formed photosensitive layer, a support, a photosensitive layer, and a cover film are sequentially laminated, and a photosensitive dry film having films on both surfaces of the photosensitive layer can also be manufactured. The cover film is peeled off when using a photosensitive dry film,
By providing the cover film on the photosensitive layer before use, the photosensitive layer can be protected and the photosensitive dry film has excellent shelf life. As the cover film, the same one as the polymer film used for the support described above can be used, and the cover film and the support may be the same material or different materials, and also have a thickness. It may be the same or different.

To form an insulating protective film on a printed wiring board using a photosensitive dry film, first,
A bonding step of bonding the photosensitive layer of the photosensitive dry film and the substrate is performed. Here, when the photosensitive dry film provided with the cover film is used, the cover film is peeled off to expose the photosensitive layer, and then the substrate is brought into contact with the substrate. Then, the photosensitive layer and the substrate are 40 to 40 apart by a pressure roller or the like.
A photosensitive layer is laminated on the substrate by thermocompression bonding at about 120 ° C. Then, the support is peeled off from the photosensitive layer. Then, an exposure step of exposing the photosensitive layer through a negative mask having a desired exposure pattern, a developing step of removing an unexposed portion with a developing solution and developing, and a thermosetting step of thermally curing the photosensitive layer are performed. Thus, it is possible to manufacture a printed wiring board having an insulating protective coating on the surface of the board. An insulating resin layer may be formed between the layers of the multilayer printed wiring board by using such a photosensitive dry film. As the actinic light and the developing solution used for the exposure, those mentioned above can be similarly used.

Such a photosensitive composition simultaneously satisfies the properties relating to the formation of a photosensitive film such as photosensitivity, developability and shelf life, and the properties as an insulating protective film such as heat resistance, hardness and dimensional stability. It is possible to form a cured film having flexibility. In particular, an interlayer compound in which at least one thermal polymerization catalyst selected from the group consisting of amine, quaternary ammonium salt, acid anhydride, polyamide, nitrogen-containing heterocyclic compound, and organometallic compound is inserted into the inorganic layered compound (D ), It is particularly excellent in shelf life.
In addition, since the inorganic layered compound is nano-dispersed, a cured film having excellent heat resistance and dimensional stability can be formed without using a large amount of epoxy resin (B). Such a photosensitive composition is most suitable for use as an insulating protective film for thin wiring boards such as FPC boards.

[0065]

The present invention will be described in more detail with reference to the following examples. As the compound (A) having an ethylenically unsaturated group, the following <EA> (epoxy (meth) acrylate compound having a carboxyl group) in Production Example 1 and the following <PUA-1 to 2> in Production Examples 2 to 3 ( Urethane (meth) acrylate compound having a carboxyl group)
In Production Examples 4 and 5 were the intercalation compounds 1 and 2
Was synthesized. [Production Example 1] <EA> Epoxy equivalent is 178, and the average per molecule is 3.
A reaction product obtained by reacting 1 equivalent of a phenol novolac type epoxy resin having 6 phenol nucleus residues and an epoxy group together with 0.95 equivalent of acrylic acid was added with hexahydrophthalic anhydride. 0.78 equivalents were reacted by a conventional method using diethylene glycol diacrylate as a solvent. This product was a viscous liquid containing 35 parts by mass of diethylene glycol diacrylate and had an acid value of solid content of 72.8 mgKOH / g. Viscosity (25
C.) was 10,000 mPa.s.

[Production Example 2] <PUA-1> Polycaprolactam diol (manufactured by Daicel Chemical Industries, Ltd.)
Manufactured by PLACCEL 208, molecular weight 830) 249 g
(= 0.3 mol), as a dihydroxyl compound having a carboxyl group, dimethylolpropionic acid 40.
2 g (= 0.3 mol), isophorone diisocyanate as polyisocyanate 155.4 g (= 0.7 mo)
1) was weighed and heated to 50 ° C. Further, 150 mg of di-n-dibutyltin dilaurate was added and heated to 80 ° C. Furthermore, p-methoxyphenol and di-t-
After adding 90 mg each of butylhydroxytoluene,
2 as a (meth) acrylate having a hydroxyl group
-Hydroxyethyl acrylate 24.4 g (= 0.2
1 mol) was added. Stirring is continued at 80 ° C., and the absorption spectrum of the isocyanate group (22
After confirming that 80 cm ^-1 ) had disappeared, the reaction was terminated and urethane acrylate was obtained. Carbitol acetate was used as the solvent during the synthesis. Thus, a viscous liquid urethane acrylate (PUA-1) having a solid content acid value of 36 mgKOH / g and a solid content concentration of 60 mass% was obtained. The number average molecular weight of this product is 10
000 and viscosity (25 ° C.) were 19000 mPa · s.

[Production Example 3] <PUA-2> Polytetramethylene glycol (PTG-850SN manufactured by Hodogaya Chemical Co., Ltd., molecular weight 8) was used as the polymer polyol.
50) 85, 0 g (= 0.1 mol), dimethylolpropionic acid 93.8 g (= 0.7 mol) as a dihydroxyl compound having a carboxyl group, and isophorone diisocyanate 19 as a polyisocyanate compound
A urethane acrylate was produced in the same manner as in Production Example 2 except that 9.8 g (= 0.9 mol) and 24.4 g (= 0.21 mol) of 2-hydroxyethyl acrylate were used as the (meth) acrylate having a hydroxyl group. <PUA-2> was obtained. The obtained urethane acrylate <PUA-2> had a mass average molecular weight of 8000, a solid content concentration of 50 mass%, a solid content acid value of 90 mgKOH / g, and a viscosity (25 ° C) of 11,000 mPa · s.

[Production Example 4] <Intercalation compound 1> Synthetic saponite (Kunimine Industries Co., Ltd.) was added to 4 L of distilled water.
"Smecton SA", ion exchange capacity CEC; 70me
(q / 100g) 200g was added and mixed to fully swell. This dispersion is heated to 60 ° C.
1.0 equivalent of the melamine hydrochloride aqueous solution was added to the CEC of the synthetic saponite. Then, it was sufficiently stirred to carry out an ion exchange reaction. The suspension is filtered and washed,
Filtration was repeated, dried and pulverized to obtain a fine powder of intercalation compound 2. Using this intercalation compound 1, Cu-Kα ray,
As a result of powder X-ray diffraction measurement at kV and 30 mA, the bottom distance of the obtained intercalation compound 1 was 1.3 nm, and the amount of melamine between layers obtained by thermogravimetric (TG) measurement was 12% by mass. .

[Production Example 5] <Intercalation compound 2> 200 g of synthetic tetrasilicon mica (“Somasif ME-100” manufactured by Coop Chemical Co., ion exchange capacity CEC; 107 meq / 100 g) was previously dispersed in 4 L of distilled water. Then, dodecyl (2-hydroxyethyl) methylammonium chloride ("Esoguard C / 12" manufactured by Lion Akzo Co., Ltd.) was added thereto in an amount of 1.5 equivalents relative to CEC, and sufficiently stirred to carry out an ion exchange reaction. The suspension was filtered, washed and filtered repeatedly, dried and pulverized to obtain an intercalation compound.
As a result of powder X-ray diffraction measurement using Cu-Kα ray at 40 kV and 30 mA, the bottom surface interval was 1.9 nm, and T
The amount of inter-layer dodecyl (2-hydroxyethyl) methylammonium chloride determined by G measurement was 21% by mass. Then, a 20% by mass suspension of this intercalation compound in ethyl acetate and a 20% by mass solution of benzyldimethylamine (BDMA) in ethyl acetate were mixed at a mass ratio of 3: 2. After mixing, removing the solvent, and pulverizing, a fine powder of intercalation compound 2 was obtained. This intercalation compound 2
Powder X with Cu-Kα ray at 40 kV and 30 mA.
As a result of line diffraction measurement, the bottom distance of the obtained intercalation compound 2 was 2.3 nm, and the dodecyl (2
The total amount of -hydroxyethyl) methylammonium chloride and BDMA was 29% by mass in the intercalation compound 2.

[Examples 1 to 4 and Comparative Examples 1 and 2] Photosensitive compositions were prepared by mixing the components in the mixing ratios shown in Table 1. As the compound (A) having an ethylenically unsaturated group, <EA> and <PU produced in the above Production Examples 1 to 3 are used.
A-1 to 2>, urethane acrylate, EB1290
K (manufactured by Daicel Chemical Industries, Ltd.) was used. As the epoxy resin (B), novolac type epoxy resin E
PPN502H (manufactured by Nippon Kayaku Co., Ltd.) and biphenyl type epoxy resin YL6121H (manufactured by Chapan Epoxy Resins Co., Ltd.) were used. As the photopolymerization initiator (C),
2,4,6-Trimethylbenzoyldiphenylphosphine oxide TPO (manufactured by BASF), 4,4′-bis (diethylamino) benzophenone EAB-F (manufactured by Hodogaya Chemical Co., Ltd.), aminoacetophenone system
Irgacure 369 (manufactured by Ciba Specialty Chemicals Co., Ltd.) was used. As the intercalation compound (D), <intercalation compounds 1 to 1 produced in the above Production Examples 4 and 5 were used.
2> was used. Melamine was used as an anti-copper agent.

[0071]

[Table 1] The numerical value in Table 1 shows solid content mass (g).

[Test Example 1] (Preparation of laminate test piece) Each of the photosensitive compositions prepared in Examples 1 to 4 and Comparative Examples 1 and 2 was dried on a substrate for evaluation so that the film thickness after drying was about 30 μm
Was applied by screen printing with a 150 mesh polyester plate. The applied photosensitive composition is 70
The laminate was dried at 30 ° C. for 30 minutes to prepare a laminate test piece. The final film thickness of the photosensitive layer was 30 ± 2 μm. The following (1) and (2) were used as the evaluation substrates. (1) A printed circuit board [UPICELL (registered trademark) N] made of a polyimide film (thickness: 50 μm) having a copper foil (thickness: 35 μm) laminated on one side was washed with a 1% sulfuric acid aqueous solution, washed with water, and then dried with an air stream. What I did. (2) 25 μm polyimide film [Kapton (registered trademark) 100H, manufactured by Toray DuPont Co., Ltd.]

[Exposure, Development, and Heat Curing of Laminated Test Pieces] After a negative having an exposure pattern was overlaid on each laminated test piece obtained above, an exposure machine having a metal halide lamp [manufactured by Oak Co., Ltd.] 500 with HMW-680GW
It was exposed at mJ / cm ² . Next, by spraying a 1 mass% sodium carbonate aqueous solution at 30 ° C. for 60 seconds,
After removing the unexposed portion and developing, heat treatment is performed at 150 ° C. for 30 minutes to obtain a copper-clad laminate (using the evaluation substrate (1)) and a polyimide laminate (using the evaluation substrate (2)). It was
The physical properties of these materials were evaluated as follows. The results are shown in Table 2. In addition, in each of the following evaluations, the “warpage deformation” was evaluated for the polyimide laminated plate.
In each of the other evaluations, the copper-clad laminate was evaluated.

[Evaluation Items] Pencil hardness According to the JIS K-5400 test method, a pencil hardness tester was used, and a hardness of 1 kg was applied to the cured film. As the pencil, Mitsubishi High Uni (manufactured by Mitsubishi Pencil Co., Ltd.) was used. -Soldering heat resistance According to the test method of JIS C-6481, the copper-clad laminate is floated in a solder bath at 260 ° C for 10 seconds.
As a cycle, "blister" and adhesion of the cured film of the copper clad laminate after 1 cycle and 3 cycles were comprehensively evaluated for evaluation. The abbreviations in Table 2 indicate the following. ⊚: No change observed ○: Slight change Δ: Less than 10% of the cured film peeled off ×: Cured film peeled off entirely ・ Sledding deformation polyimide laminate (30 mm × (30 mm) as a test piece, one apex of the test piece was pressed on a plane, the distance between the apex and the plane at a position diagonal to the apex was measured, and the maximum value was measured as the warp deformation amount.

[Test Example 2] (Preparation of laminate test piece) Each of the photosensitive compositions prepared in Examples 1 to 4 and Comparative Examples 1 and 2 was used on a film made of polyethylene terephthalate having a thickness of 23 μm and a doctor blade was used. And apply it at 80 ℃,
After forming the photosensitive layer by drying for 20 minutes, 30μ on it
A low-density polyethylene film having a thickness of m was laminated to prepare a photosensitive dry film having a cover film. The film thickness of the photosensitive layer after drying was 30 ± 1 μm. For these, the shelf life of the photosensitive layer was evaluated by the method described below. The results are shown in Table 2. [Evaluation items] The photosensitive dry film immediately after the shelf life was manufactured and 7 in the dark at 23 ° C.
The photosensitivity and developability of the photosensitive dry film after storage for one day were evaluated and compared as follows.・ As a photosensitivity negative, a 21-step step tablet (manufactured by Hitachi Chemical Co., Ltd.) is placed on the photosensitive layer, exposed, and developed, and the number of steps of the photocured film remaining after development is measured. The sensitivity was evaluated. Regarding the photosensitivity, the higher the number of steps of the step tablet, the higher the photosensitivity. -At the time of developing photosensitivity evaluation, the state of the coating film was visually evaluated after 1 minute development using a 1% by mass sodium carbonate aqueous solution as a developing solution at a temperature of 30 ° C and a spray pressure of 2 kg / cm ² during development. did. The abbreviations in Table 2 indicate the following. ◯: What was developed Δ: There was some development residue X: There was development residue

[0076]

[Table 2]

[0077]

As described above, the photosensitive composition of the present invention comprises the compound (A) having an ethylenically unsaturated group, the epoxy resin (B), the photopolymerization initiator (C), and the inorganic layered structure. An intercalation compound (D) in which at least one thermal polymerization catalyst selected from the group consisting of amine, quaternary ammonium salt, acid anhydride, polyamide, nitrogen-containing heterocyclic compound, and organometallic compound is inserted into the compound Therefore, the performance relating to the formation of the photosensitive coating such as photosensitivity, developability and shelf life, and the performance as an insulating protective coating such as heat resistance, hardness and dimensional stability can be satisfied at the same time, and it has flexibility. A cured film can be formed. Therefore, the photosensitive composition of the present invention does not warp when used as an insulating protective coating for thin wiring boards such as FPC boards, and is optimal for use on such thin wiring boards.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Zenichi Kanamaru             96-25 Motomachi Hachioji-cho, Hachioji-shi, Tokyo F term (reference) 2H025 AA13 AB15 AC01 AD01 BC13                       BC42 BC66 BC74 BC86 CA00                       CB30 CC20                 5E314 AA25 AA27 AA32 AA42 BB02                       BB11 BB12 CC15 FF06 GG08                       GG19

Claims (20)

[Claims] 1. A compound (A) having an ethylenically unsaturated group, an epoxy resin (B), and a photopolymerization initiator (C).
And an intercalation compound in which at least one thermal polymerization catalyst selected from the group consisting of amine, quaternary ammonium salt, acid anhydride, polyamide, nitrogen-containing heterocyclic compound, and organometallic compound is inserted into the inorganic layered compound (D ) And a photosensitive composition. 2. The photosensitive composition according to claim 1, wherein the content of the intercalation compound (D) is 1 to 20 mass%. 3. The photosensitivity according to claim 1, wherein the inorganic layered compound is at least one selected from a cation-exchangeable layered compound, an anion-exchanged layered compound and a layered compound derived therefrom. Composition. 4. The photosensitive composition according to claim 3, wherein the cation-exchange layered compound is a layered silicate. 5. The photosensitive composition according to claim 3, wherein the anion-exchange layered compound is a hydrotalcite compound. 6. The compound (A) having an ethylenically unsaturated group is at least one of an epoxy (meth) acrylate compound (A1) having a carboxyl group and a urethane (meth) acrylate compound (A2) having a carboxyl group. The photosensitive composition according to any one of claims 1 to 5, further comprising: 7. The solid content acid value of the epoxy (meth) acrylate compound (A1) having a carboxyl group is 10 m.
gKOH / g or more and 160 mgKOH / g or less,
The urethane (meth) acrylate compound (A2) having a carboxyl group has a solid acid value of 5 mgKOH / g or more 1
It is 50 mgKOH / g or less, The photosensitive composition of Claim 6 characterized by the above-mentioned. 8. A group consisting of a (meth) acrylate compound (A3) having a hydroxyl group, a glycidyl (meth) acrylate compound (A4) and a urethane acrylate (A5) as the compound (A) having an ethylenically unsaturated group. The photosensitive composition according to claim 6, further comprising at least one selected from the group consisting of: 9. A heterogeneous system containing a dispersed phase comprising an epoxy resin (B), wherein the epoxy resin (B) is a bisphenol S type epoxy resin, a diglycidyl phthalate resin, a heterocyclic epoxy resin, a bixylenol type. 9. The photosensitive composition according to claim 1, which is at least one selected from the group consisting of an epoxy resin, a biphenol type epoxy resin, and a tetraglycidylxylenoylethane resin. 10. The photopolymerization initiator (C) is used in an amount of 0.1 parts by weight per 100 parts by weight of the compound (A) having an ethylenically unsaturated group.
The photosensitive composition according to any one of claims 1 to 9, which is blended in an amount of 1 to 20 parts by mass. 11. The photosensitive composition according to claim 1, which further contains an organic solvent. 12. A viscosity of 500 to 500,000 mPa.
The photosensitive composition according to claim 1, wherein the photosensitive composition is s. 13. A cured product obtained by curing the photosensitive composition according to any one of claims 1 to 12. 14. The photosensitive composition according to claim 1 is applied onto a substrate in a thickness of 10 to 100 μm, and then in a temperature range of 60 ° C. to 100 ° C. for 5 minutes to 30 minutes.
A method for curing a photosensitive composition, which comprises drying for minutes, exposing and developing, and then thermosetting. 15. A photosensitive dry film having a photosensitive layer formed of the photosensitive composition according to claim 1 on a support. 16. A method for producing a photosensitive dry film, which comprises a photosensitive layer forming step of coating the photosensitive composition according to any one of claims 1 to 12 on a support and drying it. 17. An insulating protective film comprising the photosensitive composition according to any one of claims 1 to 12. 18. A printed wiring board having the insulating protective film according to claim 17. 19. The printed wiring board according to claim 18, which is a flexible printed wiring board. 20. A bonding step of bonding the photosensitive layer of the photosensitive dry film according to claim 15 and a substrate, an exposing step of exposing the photosensitive layer, a developing step after the exposing step, and a photosensitive layer. A method of manufacturing a printed wiring board, comprising: a heat curing step of heat curing.