JP2002229201A - Photosensitive composition, its cured body and printed wiring board using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive composition having fair appearance and flexibility, excellent in photosensitivity and developability and also having good performances such as heat resistance, electric insulating property and adhesion to a wiring substrate. SOLUTION: The photosensitive composition contains a photo-curable component containing a urethane(meth)acrylate compound (A) having a carboxyl group and a compound (B) having an ethylenically unsaturated group and other than the compound (A), a thermosetting resin (C), a photopolymerization initiator (D) and a thermopolymerization catalyst (E). The compound (A) preferably has a number average molecular weight of 1,000-40,000 and 5-150 mgKOH/g acid value. Since the photosensitive composition is excellent particularly in flexibility, curl is not caused even when used on a thin wiring substrate and the composition is optimum for use on an FPC substrate.

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 film for a printed wiring board, a cured product thereof, a curing method, and uses of the photosensitive composition.

[0002]

2. Description of the Related Art A protective film made of polyimide or polyester is widely used as an insulating protective film for a wiring board. When providing this protective film on a 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 perforated by a method such as punching, and the protective film is manually positioned on the wiring board while being overlapped. Using high temperature and high pressure bonding.

[0003] Polyimide, polyester, and the like have a certain degree of flexibility and are suitable for wiring protection. However, in order to lead the wiring terminals on the wiring board, it is necessary to punch the film in advance and make holes. Therefore, when the wiring becomes complicated, it becomes difficult to align the film with the wiring on the substrate. In addition, the cost of equipment such as a hot plate press is high, and an adhesive must be used, which increases the cost. In addition, there is a problem that smear is generated at the time of punching, and that the adhesive oozes out at the time of pressing.

In addition, even if a protective film having excellent heat resistance and electrical insulation is used as an insulating protective film in such a method, as long as the wiring board and the protective film are bonded via an adhesive, In some cases, the performance of the adhesive affected the insulating protective film, and the heat resistance and electrical insulation of the insulating protective film were sometimes reduced.

Therefore, recently, a method of forming an insulating protective film on a wiring board by a printing method using coverlay ink (hereinafter, referred to as “coverlay ink method”) has been studied. As an example of coverlay ink, see JP-A-5
JP-A-5-145717 discloses a composition comprising an epoxy (meth) acrylate resin and a melamine resin. In addition, Japanese Patent Publication No. 50-4395, Japanese Patent Publication No. 53
No. 10636 discloses an acrylic resin composition such as sulfomethylene acrylate and ethylene phosphate acrylate. Also, JP-A-63-22117
Japanese Patent Application Laid-Open No. 2-256515 discloses a composition containing polyaminobismaleimide and an epoxy resin as main components, and JP-A-1-121364 discloses a composition mainly containing polyimide. , Polyparabanic acid, and an epoxy resin-based composition are disclosed.

[0006]

However, the insulating protective film obtained by the coverlay ink method has insufficient flexibility, heat resistance, and electrical insulation, and has poor adhesion to a wiring board. Often poor. Therefore, when used for a thin wiring board such as a flexible printed wiring board (hereinafter, referred to as an “FPC board”), a difference in the coefficient of thermal expansion between the wiring board and the insulating protective coating and a curing shrinkage at the time of manufacturing the insulating protective coating cause In addition, there is a problem that the FPC board is warped (hereinafter, referred to as "curl").

For example, a coating comprising the composition disclosed in Japanese Patent Application Laid-Open No. 55-145717 has a drawback that it has poor flexibility. Further, the coatings composed of the compositions disclosed in JP-B-50-4395 and JP-B-53-10636 had extremely poor heat resistance. Further, the compositions disclosed in JP-A-63-221172, JP-A-1-121364, and JP-A-1-256515 all have a large shrinkage ratio during curing, and therefore, such When a coverlay ink film is formed on an FPC substrate using the composition or when the substrate on which the film is formed is subjected to high heat, remarkable curling occurs. In other words, it has a beautiful appearance, flexibility, excellent light sensitivity and developability, and also satisfies the performance such as heat resistance, electrical insulation, and adhesion to the wiring board. Even when used, no material that does not cause curl has been found.

[0008] The present invention has been made in view of such circumstances, and relates to the performance relating to the formation of a photosensitive film such as photosensitivity and developability, and the insulation protection such as heat resistance, electrical insulation, and adhesion to a wiring board. It is an object of the present invention to provide a photosensitive composition which can simultaneously satisfy the performance as a coating, has flexibility, and can form a cured film having good appearance.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies to improve the above-mentioned problems, and as a result, have found that a urethane (meth) acrylate compound (A) having a carboxyl group.
And a compound (B) having an ethylenically unsaturated group excluding (A), a thermosetting resin (C), and a photopolymerization initiator (D)
And a photopolymerization catalyst (E), the photosensitive composition simultaneously satisfies the above-mentioned performances, and when used as a coating material for a wiring board such as an FPC board, an insulating protective film having extremely excellent properties which has never been obtained before. And completed the present invention.

That is, the photosensitive composition of the present invention comprises a photocurable component containing a urethane (meth) acrylate compound (A) having a carboxyl group and a compound (B) having an ethylenically unsaturated group other than (A). And thermosetting resin (C)
And a photopolymerization initiator (D) and a thermal polymerization catalyst (E). The ink of the present invention is characterized by containing the photosensitive composition, an organic solvent, and a colorant. In addition, the method for curing a photosensitive composition of the present invention includes the step of coating the photosensitive composition or the ink on a substrate with a thickness of 10 to 100 μm.
After coating at a thickness of 5
After drying for 5 to 30 minutes to a thickness of 5 to 70 μm, exposure and development are followed by thermosetting. The photosensitive dry film of the present invention is characterized by having a photosensitive layer formed from the above photosensitive composition on a support.
The method for producing a photosensitive dry film of the present invention is characterized by comprising a photosensitive layer forming step of applying and drying the photosensitive composition on a support. The insulating protective film of the present invention is characterized by comprising the above photosensitive composition. A printed wiring board according to the present invention includes the above-mentioned insulating protective film. The method of manufacturing a printed wiring board according to the present invention includes: a laminating step of laminating the photosensitive layer of the photosensitive dry film to the substrate; an exposing step of exposing the photosensitive layer; a developing step after the exposing step; Is characterized by having a thermosetting step of thermosetting.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The photosensitive composition of the present invention contains a photocurable component containing a urethane (meth) acrylate compound (A) having a carboxyl group and a compound (B) having an ethylenically unsaturated group other than (A). The urethane (meth) acrylate compound (A) having a carboxyl group includes 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). Is a compound containing as a structural unit. In this compound (A), both terminals are composed of a unit derived from (meth) acrylate (a) having a hydroxyl group, and between both terminals, a unit derived from polyol (b) and a polyisocyanate ( c) derived units. The repeating unit connected by the urethane bond has a structure in which a carboxyl group exists.

That is, the urethane (meth) acrylate compound (A) having a carboxyl group is-(ORbO
-OCNHRcNHCO) n- wherein ORbO represents a dehydrogenated residue of polyol (b), and Rc represents a deisocyanate residue of polyisocyanate (c). ] Is represented.
The urethane (meth) acrylate compound (A) having a carboxyl group has at least a (meth) acrylate (a) having a hydroxyl group, a polyol (b),
It can be produced by reacting polyisocyanate (c). Here, it is necessary to use a compound having a carboxyl group for at least one of polyol (b) and polyisocyanate (c). .
Preferably, a polyol (b) having a carboxyl group
Use By using a compound having a carboxyl group as the polyol (b) and / or the polyisocyanate (c), a urethane (meth) acrylate compound (A) having a carboxyl group in Rb or Rc can be 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 at least one of the polyol (b) and the polyisocyanate (c) is used in two or more types, the repeating unit represents a plurality of types, but the regularity of the plurality of units is completely random, and the regularity of the plurality of units is block. , Localization and the like can be appropriately selected according to the purpose.

Examples of the (meth) acrylate (a) having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and caprolactone or oxidized (meth) acrylate of each of the above (meth) acrylates. Alkylene 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 adduct-di (meth) acrylate and the like can be mentioned. 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 preferred, and 2-hydroxyethyl (meth) acrylate is more preferred. 2-hydroxyethyl (meth)
Use of an acrylate makes it easier to synthesize a urethane (meth) acrylate compound (A) having a carboxyl group.

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

The polymer polyol (b1) used in the present invention includes polyether diols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol; polyester polyols obtained from esters of polyhydric alcohols and polybasic acids; Polylactone diols such as polycarbonate diols, polycaprolactone diols and polybutyrolactone diols containing units derived from methylene carbonate, pentamethylene carbonate and the like as constituent units are exemplified. When the polymer polyol (b1) having a carboxyl group is used, for example, a tribasic or higher polybasic acid such as trimellitic acid (anhydride) is allowed to coexist during the synthesis of the polymer polyol (b1), and the carboxyl group remains. Compounds synthesized as described above can be used. The polymer polyol (b1) can be used alone or in combination of two or more. Also,
As these polymer polyols (b1), those having a number average molecular weight of from 200 to 2,000 are preferred because the flexibility of the cured film made of the photosensitive composition is more excellent. Of these polymer polyols (b1), the use of polycarbonate diol is preferred because the cured film made of the photosensitive composition has high heat resistance and excellent pressure cooker resistance. Furthermore, when the structural unit of the polymer polyol (b1) is not only a single structural unit but also a plurality of structural units, the cured film made of the photosensitive composition has more excellent flexibility, so that it is more excellent. preferable. Examples of the polymer polyol (b1) having a plurality of structural units include polyether diols containing units derived from ethylene glycol and propylene glycol as structural units, and units derived from hexamethylene carbonate and pentamethylene carbonate. And the like.

As the dihydroxyl compound (b2),
Although a branched or linear compound having two alcoholic hydroxyl groups can be used, 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 (A). 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). Further, when a polymer polyol having a carboxyl group (b1) is used in combination, or when a polyisocyanate (c) described later is used having a carboxyl group, 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, 1,
Dihydroxyl compounds having no carboxyl group such as 4-cyclohexanedimethanol and hydroquinone (b
2) may be used.

The polyisocyanate (c) used in the present invention is specifically exemplified by 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, diphenyl Methylene diisocyanate, (o, m,
Or p) -xylene diisocyanate, methylene bis (cyclohexyl isocyanate), trimethylhexamethylene diisocyanate, cyclohexane-1,3-
Dimethylene diisocyanate, cyclohexane-1,4
Diisocyanates such as dimethylene diisocyanate and 1,5-naphthalenedi isocyanate. These polyisocyanates can be used alone or in combination of two or more. Further, a polyisocyanate (c) having a carboxyl group can be used.

The urethane (meth) acrylate compound (A) having a carboxyl group used in the present invention has a number average molecular weight of 1,000 to 40,000 and an acid value of 5-1.
Those having a concentration of 50 mgKOH / g are preferred. Here, the number average molecular weight is a value in terms of polystyrene measured by gel permeation chromatography. Further, the number average molecular weight is more preferably 8,000 to 30,000, and the acid value is 30 to 120 mgKOH / g. If the number average molecular weight of the urethane (meth) acrylate compound (A) having a carboxyl group is less than 1,000, the elongation and strength of a cured film made of the photosensitive composition may be impaired.
If it exceeds 0000, it may be hard and may have reduced flexibility. If the acid value is less than 5 mgKOH / g, the alkali solubility of the photosensitive composition may be deteriorated.
If it exceeds mgKOH / g, the alkali resistance and electric properties of the cured film may be deteriorated. The acid value of the urethane (meth) acrylate compound (A) having a carboxyl group is 5
１５０150 mg KOH is preferable, but in this range, if the acid value is increased, the developability is improved, but the flexibility tends to decrease, and if the acid value is decreased, the flexibility increases. In addition, there is a tendency that developability is reduced and development residue is apt to occur. Therefore, by using a urethane (meth) acrylate compound (A) having at least two different carboxyl groups having different acid values in combination, a photosensitive composition having excellent flexibility and good developability can be obtained. It has been found that it can be easily obtained. In particular, a urethane (meth) acrylate compound having a carboxyl group having an acid value of 5 mgKOH / g or more and less than 60 mgKOH / g, and an acid value of 60 mgKOH / g or more and 150 mgKO
Urethane (meth) having a carboxyl group of H / g or less
It is preferable to select at least one or more acrylate compounds. Further, when used in combination, the acid content is 5 mgKOH / g or more and 60 mgKOH / g or more.
/ G is preferably an excess, more specifically, an acid value of 5 mgK in 100 parts by mass of a urethane (meth) acrylate compound (A) having a carboxyl group.
OH / g or more and less than 60 mgKOH / g: acid value is 60 m
gKOH / g or more and 150 mgKOH / g or less = 60 to
The mass ratio is more preferably 90:40 to 10.

Urethane (meth) having a carboxyl group
The acrylate compound (A) is prepared by (1) a method in which (meth) acrylate (a) having a hydroxyl group, a polyol (b), and a polyisocyanate (c) are mixed and reacted at a time, and (2) a polyol (b) ) Is reacted with 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-containing (meth) A method of reacting an acrylate (a), (3) reacting a (meth) acrylate (a) having a hydroxyl group with a polyisocyanate (c), and a urethane isocyanate containing one or more isocyanate groups per molecule. Method for reacting a prepolymer with a polyol (b) after producing a nate prepolymer It can be prepared by etc..

The compound (B) having an ethylenically unsaturated group contained in the photocurable component in the photosensitive composition is other than the urethane (meth) acrylate compound (A) having a carboxyl group. It is used for the purpose of adjusting the viscosity of an object or adjusting physical properties such as heat resistance and flexibility when a photosensitive composition is cured.
Preferably, (meth) acrylic acid esters are used. Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, ter
t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) Alkyl (meth) acrylates such as acrylates; alicyclic (such as cyclohexyl (meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and dicyclopentenyloxyethyl (meth) acrylate (Meth) acrylate; benzyl (meth) acrylate, phenyl (meth) acrylate, phenylcarbitol (meth)
Acrylate, nonylphenyl (meth) acrylate,
Aromatic (meth) acrylates such as nonylphenyl carbitol (meth) acrylate and nonylphenoxy (meth) acrylate; 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate,
Having a hydroxyl group such as hydroxybutyl (meth) acrylate, butanediol mono (meth) acrylate, glycerol (meth) acrylate, phenoxyhydroxypropyl (meth) acrylate, polyethylene glycol (meth) acrylate, or glycerol di (meth) acrylate ( (Meth) acrylate; 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, 2-tert-
(Meth) acrylate having an amino group such as butylaminoethyl (meth) acrylate; methacrylate having a phosphorus atom such as methacryloxyethyl phosphate, bis-methacryloxyethyl phosphate, methacryloxyethyl phenyl acid phosphate (phenyl P) 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, Propylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,4-butanediol di (meth)
Diacrylates such as acrylate, 1,3-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and bisglycidyl (meth) acrylate; trimethylolpropane Polyacrylates such as tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate; bisphenol S ethylene oxide 4 mol modified diacrylate, bisphenol A
Bis (acryloyloxyethyl); modified polyol polyacrylates such as ethylene oxide 4 mol modified diacrylate, fatty acid modified pentaerythritol diacrylate, trimethylolpropane propylene oxide 3 mol modified triacrylate, and trimethylolpropane propylene oxide 6 mol modified triacrylate; ) Polyacrylates having an isocyanuric acid skeleton, such as monohydroxyethyl isocyanurate, tris (acryloyloxyethyl) isocyanurate, and ε-caprolactone-modified tris (acryloyloxyethyl) isocyanurate; α, ω-diacryloyl- (bisethylene glycol) -Phthalate, α, ω-tetraacryloyl-
Polyester acrylates such as (bistrimethylolpropane) -tetrahydrophthalate; glycidyl (meth) acrylate; allyl (meth) acrylate;
Hydroxyhexanoyloxyethyl (meth) acrylate; polycaprolactone (meth) acrylate; (meth) acryloyloxyethyl phthalate; (meth) acryloyloxyethyl succinate; 2-hydroxy-3-phenoxypropyl acrylate; phenoxyethyl acrylate, and the like. Can be

Further, N-vinyl compounds such as N-vinylpyrrolidone, N-vinylformamide and N-vinylacetamide, polyester acrylates, urethane acrylates, epoxy acrylates and the like are also compounds (B) having an ethylenically unsaturated group. It can be suitably used.
Among these, preferred are (meth) acrylate, glycidyl (meth) acrylate and urethane acrylate having a hydroxyl group. As the (meth) acrylate having a hydroxyl group, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (Meth) acrylate, hydroxybutyl (meth)
Acrylate and urethane acrylate. In addition, those having three or more ethylenically unsaturated groups are preferable because of increased heat resistance.

Urethane (meth) having a carboxyl group
The mixing ratio of the acrylate compound (A) and the compound (B) having an ethylenically unsaturated group other than (A) is 9 by mass.
5: 5 to 50:50, preferably 90:10 to 60: 4
0, more preferably 85:15 to 70:30.
When the blending amount of the component (A) exceeds 95% by mass, the solder heat resistance of the cured film made of the photosensitive composition may decrease. When the blending amount of the component (A) is less than 50% by mass, the photosensitivity may be reduced. The alkali solubility of the composition tends to decrease.

Further, as the photo-curing component of the photosensitive composition, an epoxy (meth) acrylate compound (F) having a carboxyl group may be further used, if necessary. The epoxy (meth) acrylate compound (F) having a carboxyl group is obtained by reacting an epoxy compound with (meth) acrylic acid and an acid anhydride. The epoxy compound used here is not particularly limited, but a bisphenol A epoxy compound, a bisphenol F epoxy compound, a bisphenol S epoxy compound, a phenol novolak epoxy compound, a cresol novolak epoxy compound, or An epoxy compound such as an aliphatic epoxy compound may be used. Examples of the acid anhydride include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, endmethylenetetrahydrophthalic anhydride, and methylend anhydride. Dibasic acid anhydrides such as methylenetetrahydrophthalic acid, chlorendic anhydride, and methyltetrahydrophthalic anhydride; and aromatic polycarboxylic anhydrides such as trimellitic anhydride, pyromellitic anhydride, and benzophenonetetracarboxylic dianhydride , 5-
(2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride,
Endobicyclo- [2,2,1] -hept-5-ene-
2,3-dicarboxylic anhydride and the like.

The epoxy (meth) acrylate compound (F) having a carboxyl group has an acid value of 10 mg.
KOH / g or more, preferably 45 KOH / g or more.
~ 160 mgKOH / g, more preferably 50 ~ 1
40 mgKOH / g. When the epoxy (meth) acrylate compound (F) having such an 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. Acid value is 10mgKO
If it is less than H / g, the alkali solubility will be poor, and if it is too large, depending on the constituents of the photosensitive composition, the properties of the cured film, such as alkali resistance and electrical properties, may be reduced. When the epoxy (meth) acrylate compound (F) having a carboxyl group is used, the epoxy (meth) acrylate compound (F) having a carboxyl group should be used in an amount of 100 parts by mass or less based on 100 parts by mass of the urethane (meth) acrylate compound (A) having a carboxyl group. Is preferred.

The thermosetting resin (C) used in the present invention
Is a thermosetting resin contained in the photosensitive composition as a thermosetting component. As the thermosetting resin (C), a thermosetting resin which is itself cured by heat, or a thermosetting resin which reacts with a carboxyl group of (A) by heat. Good. Specifically, an epoxy resin, a phenol resin, a silicone resin, a melamine derivative (eg, hexamethoxymelamine, hexabutoxylated melamine, condensed hexamethoxymelamine, etc.), a urea compound (eg, dimethylol urea, etc.), bisphenol A
Series compounds (eg, tetramethylol / bisphenol A), oxazoline compounds, oxetane compounds, and the like. These thermosetting resins can be used alone or in combination of two or more. Of these, epoxy resins are preferred. Specific examples of the epoxy resin include bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolak type epoxy resin, and phenol. Novolak epoxy resin, cresol novolak epoxy resin, N-glycidyl epoxy resin, bisphenol A novolak epoxy resin, chelate epoxy resin, glyoxal epoxy resin, amino group-containing epoxy resin, rubber-modified epoxy resin, dicyclopentadiene Epoxy compounds having two or more epoxy groups in one molecule, such as a phenolic epoxy resin, a silicone-modified epoxy resin, and an ε-caprolactone-modified epoxy resin. Further, in order to impart flame retardancy, a structure in which atoms such as halogen such as chlorine and bromine and phosphorus such as phosphorus are introduced into the structure in a bonded state that is not easily decomposed by heat or water may be used. 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 xylenoylethane resin and the like may be used. These epoxy resins can be used alone or in combination of two or more.

The photosensitive composition of the present invention is preferably a heterogeneous system containing a phase composed of an epoxy resin. Specifically, in the photosensitive composition before curing, such as a state where a solid or semi-solid epoxy resin is recognized, the epoxy resin is mixed unevenly in the photosensitive composition. It is in the state that it is. Further, the particle size is preferably such that it does not hinder screen printing. For example, this includes that the entire photosensitive composition before curing is not uniformly transparent and at least a part is opaque. in this way,
It is preferable that the photosensitive composition before curing is a heterogeneous system containing a phase composed of an epoxy resin, because the pot life of the photosensitive composition becomes long. Preferred epoxy resins include:
Bisphenol S type epoxy resin, diglycidyl phthalate resin, heterocyclic epoxy resin, bixylenol type epoxy resin, biphenyl type epoxy resin and tetraglycidyl xylenoyl ethane resin, and the phase composed of these epoxy resins is photosensitive It is preferable that the photosensitive composition contained in the composition before curing is in a heterogeneous system. As described above, as the epoxy resin in which the photosensitive composition before curing becomes a heterogeneous system, it is easy to form a heterogeneous system that is a crystal having a distinct melting point, and further, a cured product having high heat resistance is obtained. In that
Biphenyl type epoxy resins are more preferred.

In the photosensitive composition of the present invention, the blending amount of the thermosetting resin (C) is preferably from 10 to 150 parts by mass based on 100 parts by mass of the photocurable component in total.
More preferably, it is 10 to 50 parts by mass. If the amount of the thermosetting resin (C) is less than 10 parts by mass, the cured film made of the photosensitive composition may have insufficient solder heat resistance. On the other hand, when the amount exceeds 150 parts by mass, the amount of shrinkage of the cured film increases, and when the cured film is used as an insulating protective film of an FPC board, warpage (curl) tends to increase.

The photopolymerization initiator (D) used in the present invention includes benzophenone, benzoylbenzoic acid, 4-phenylbenzophenone, hydroxybenzophenone,
Benzophenones such as 4,4'-bis (diethylamino) benzophenone, benzoin alkyl ethers such as benzoin, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether and benzoin isobutyl ether, 4-phenoxydichloroacetophenone, 4-t-butyl- Dichloroacetophenone, 4-t-butyl-trichloroacetophenone, diethoxyacetophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-
Acetophenones such as 1; thioxanthenes such as thioxanthene, 2-chlorothioxanthene, 2-methylthioxanthene and 2,4-dimethylthioxanthene; alkylanthraquinones such as ethylanthraquinone and butylanthraquinone; and 2,4,6- Acylphosphine oxides such as trimethylbenzoyldiphenylphosphine oxide; benzyldimethylketals such as 2,2-dimethoxy-1,2-diphenylethan-1-one;
-Methyl-1- [4- (methylthio) phenyl] -2-
Morpholinopropan-1-one, 2-benzyl-2-
Dimethylamino-1- (4-morpholinophenyl)-
Α-aminoketones such as butanone-1, 2-hydroxy-2-methyl-1-phenyl-propan-1-one,
1- [4- (2-hydroxyethoxy) phenyl] -2
Α-hydroxy ketones such as -hydroxy-2-methyl-propan-1-one; and 9,10-phenanthrenequinone. These can be used alone or as a mixture of two or more. Further, a photosensitizer can be used in combination as needed.

Among these photopolymerization initiators (D),
Benzophenones, acetophenones, acylphosphine oxides, α-aminoketones, α-hydroxyketones are preferred, and 4,4′-bis (diethylamino) benzophenone, 2-benzyl-2-dimethylamino-1- (4 -Morpholinophenyl) -butanone-
1,2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-one (4-morpholinophenyl) -butanone-1,1-hydroxy-cyclohexyl-phenyl ketone is preferred because of its high wavelength absorption efficiency and high activity.

The mixing amount of these photopolymerization initiators (D) is
Photocurable urethane (meth) acrylate compound (A) having a carboxyl group, compound (B) having an ethylenically unsaturated group other than (A), and epoxy compound having a carboxyl group optionally blended For a total of 100 parts by mass with the (meth) acrylate compound (F),
0.1 to 20 parts by mass is preferable, and 0.2 to 10 parts by mass is more preferable. When the compounding amount of the photopolymerization initiator (D) is less than 0.1 part by mass, the curing of the photosensitive composition may be insufficient.

The thermal polymerization catalyst (E) used in the present invention comprises:
It exhibits an effect of thermally curing the thermosetting resin (C), and includes amines, amine salts such as chlorides of the amines, quaternary ammonium salts, cyclic aliphatic acid anhydrides, and aliphatic acid anhydrides. Acid anhydrides such as aromatic acid anhydrides; nitrogen-containing heterocyclic compounds such as polyamides, imidazoles and triazine compounds; and organometallic compounds. These can be used alone or in combination of two or more.

Examples of the amines include aliphatic and aromatic primary, secondary and tertiary amines. Examples of aliphatic amines include polymethylene diamine, polyether diamine, diethylene triamine, triethylene triamine,
Tetraethylenepentamine, triethylenetetramine,
Dimethylaminopropylamine, mensendiamine, aminoethylethanolamine, bis (hexamethylene)
Triamine, 1,3,6-trisaminomethylhexane, tributylamine, 1,4-diazabicyclo [2,
2,2] octane, 1,8-diazabicyclo [5,4,
0] undecen-7-ene and the like. Examples of the aromatic amine include metaphenylenediamine, diaminodiphenylmethane, diaminodiphonylmethane, diaminodiphenylsulfone, and the like.

Examples of the acid anhydrides include aromatic acids such as phthalic anhydride, trimellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bis (anhydrotrimellitate) and glycerol tris (anhydrotrimellitate). Examples thereof include anhydride, maleic anhydride, succinic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, polyadipic anhydride, chlorendic anhydride, and tetrabromophthalic anhydride.

Examples of the polyamides include polyaminoamides having primary and secondary amino groups obtained by subjecting polyamines such as diethylenetriamine and triethylenetetraamine to condensation reaction with dimer acid.

As the imidazoles, specifically, imidazole, 2-ethyl-4-methylimidazole, N
-Benzyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate,
2-methylimidazolium isocyanate and the like.

The triazine compound is a compound having a 6-membered ring containing three nitrogen atoms, and examples thereof include a melamine compound, a cyanuric acid compound and a melamine cyanurate compound. Specifically, examples of the melamine compound include melamine, N-ethylene melamine, N, N ′, N ″ -triphenylmelamine and the like. Examples of the cyanuric acid compound include cyanuric acid, isocyanuric acid, trimethyl cyanurate, trismethyl isocyanurate, triethyl cyanurate, trisethyl isocyanurate, tri (n-propyl) cyanurate, tris (n-propyl) isocyanurate, and diethyl cyanurate. , N,
N'-diethyl isocyanurate, methyl cyanurate, methyl isocyanurate and the like can be mentioned. Examples of the melamine cyanurate compound include an equimolar reaction product of the melamine compound and the 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, zinc 2-ethylhexanoate, 1,3-diketone metal complex salts such as nickel acetylacetonate and zinc acetylacetonate, titanium tetrabutoxide, zirconium Metal alkoxides such as tetrabutoxide and aluminum butoxide are exemplified.

The amount of the heat polymerization catalyst (E) used is 0.5 to 20 parts by mass, preferably 1 to 10 parts by mass, per 100 parts by mass of the thermosetting resin (C). If the amount of the thermal polymerization catalyst (E) is less than 0.5 parts by mass, the curing reaction does not proceed sufficiently, and the heat resistance decreases. Further, since curing at a high temperature for a long time is required, it may cause a reduction in work efficiency. If the amount is more than 20 parts by mass, it reacts with a carboxyl group in the photosensitive composition, gelation easily occurs, and problems such as a decrease in storage stability may occur.

The photosensitive composition of the present invention can be produced by mixing the above-mentioned components by a usual method. The method of mixing is not particularly limited, and some components may be mixed before the remaining components are mixed, or all components may be mixed at once. Further, an organic solvent may be added to the photosensitive composition as needed for viscosity adjustment or the like. By adjusting the viscosity in this way, it becomes easy to apply or print on the target 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; alcohol solvents such as butanol and benzyl alcohol; carbitol acetate; Solvents for cellosolves such as methyl cellosolve acetate, carbitols and their esters and ether derivatives; N, N-dimethylformamide, N, N
Amide solvents such as dimethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone; dimethylsulfoxide; phenol solvents such as phenol and cresol; nitro compound solvents; toluene, xylene, hexamethylbenzene, cumene Aromatic solvents such as aromatic and alicyclic solvents composed of hydrocarbons such as tetralin, decalin and dipentene. One type or a combination of two or more types 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 ° C. ] Is preferably adjusted. More preferably, 1,000 to 5
It is 00,000 mPa · s. With such a viscosity, it is more suitable for application or printing on an object, and is easy to use. The preferable amount of the organic solvent used for obtaining such a viscosity is 1.5 times by mass or less of the solid content other than the organic solvent. If it exceeds 1.5 times by mass, the solid content concentration becomes low, and when printing this photosensitive composition on a substrate or the like, a sufficient film thickness cannot be obtained by one printing, and many printings are required. There are cases. Further, a coloring agent may be further added to such a photosensitive composition to be used as an ink. Examples of the coloring agent include phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, and naphthalene black. Even when used as an ink, its viscosity is 500-500,
000 mPa · s [B-type viscometer (Brookfield Viscomete
Measured at 25 ° C in r). ] Is preferable.

A flow regulator can be further added to the photosensitive composition of the present invention in order to adjust the fluidity. The fluidity adjusting agent is preferable because the fluidity of the photosensitive composition can be appropriately adjusted, for example, when the photosensitive composition is applied to an object by roller coating, spin coating, screen coating, curtain coating, or the like. Flow regulators include, for example, inorganic and organic fillers, waxes, surfactants, and the like. Specific examples of the inorganic filler include talc,
Barium sulfate, barium titanate, silica, alumina,
Examples 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 surfactants include silicone oil,
Examples include higher fatty acid esters and amides. These fluidity modifiers can be used alone or in combination of two or more. In addition, among these, when the inorganic filler is used, not only the flowability of the photosensitive composition,
This is preferable because characteristics such as adhesion and hardness can be improved.

If necessary, additives such as a thermal polymerization inhibitor, a thickener, an antifoaming agent, a leveling agent, and an adhesion-imparting agent can be added to the photosensitive composition. Examples of the thermal polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol, and phenothiazine. As a thickener,
Asbestos, Olben, Benton, Montmorillonite and the like can be mentioned. The defoaming agent is used to eliminate bubbles generated during printing, coating and curing, and specific examples include surfactants such as acrylics and silicones. The leveling agent is used to eliminate irregularities on the film surface generated during printing and coating, and specific examples include an acrylic-based, silicon-based, and other surfactants. As the adhesion promoter,
Examples thereof include imidazole, thiazole, triazole, and silane coupling agents. Further, as other additives, for example, an ultraviolet ray inhibitor, a plasticizer and the like for storage stability can be added as long as the gist of the present invention is not impaired.

The photosensitive composition of the present invention is applied on a substrate or the like at an appropriate thickness, heat-treated and dried.
A cured product can be obtained by curing by development and thermal curing. The photosensitive composition of the present invention can be used for various applications. In particular, the photosensitive composition is excellent in photosensitivity, developability, and adhesion to a substrate when cured into a thin film, insulation, heat resistance, and warpage. Since it is excellent in deformability, flexibility, and appearance, it is suitable for use as an insulating protective film on a printed wiring board. When forming an insulating protective film, a photosensitive composition or ink is applied on a substrate on which a circuit is formed by 10 μm to 100 μm.
m, heat-treated in a temperature range of 60 ° C to 100 ° C for about 5 to 30 minutes, and dried,
m, and then exposed through a negative mask on which a desired exposure pattern has been formed, unexposed portions are removed with a developing solution and developed, and at a temperature range of 100 ° C to 180 ° C, 10 to 40 ° C.
For example, a method of curing by heat-curing for about a minute may be used. This photosensitive composition is particularly excellent in flexibility when it is made into a cured product, and is excellent in flexibility. Therefore, the photosensitive composition is particularly suitable for use as an insulating protective film of an FPC board, has less curl, and has excellent handleability. FPC board. Further, 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 exposure, a known active light source, for example, active light generated from a carbon arc, a mercury vapor arc, a xenon arc, or the like is used. The sensitivity of the photopolymerization initiator (D) contained in the photosensitive layer is usually maximum in the ultraviolet region, and in that case, the active light source preferably emits ultraviolet light effectively. Of course, those in which the photopolymerization initiator (D) 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 bulb, a sun lamp, or the like is used as the light source in addition to the active light source. Further, as the developer, an aqueous alkali solution such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, and amines can be used.

Further, the photosensitive composition of the present invention can be used for a photosensitive layer of a photosensitive dry film. The photosensitive dry film has a photosensitive layer composed of a photosensitive composition on a support composed of a polymer film or the like. The thickness of the photosensitive layer is preferably from 10 to 70 μm. Examples of the polymer film used for the support include polyethylene terephthalate, polyester resins such as aliphatic polyesters, polypropylene, and films made of polyolefin resins such as low-density polyethylene. Films made of polyethylene are preferred. In addition, since these polymer films need to be removed from the photosensitive layer later, it is preferable that these polymer films can be easily removed from the photosensitive layer. The thickness of these polymer films is usually 5 to 100 μm, preferably 10 to 30 μm.

The photosensitive dry film can be produced by a photosensitive layer forming step in which a photosensitive composition is coated on a support and dried. 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 be manufactured. The cover film is peeled off when using the photosensitive dry film,
By providing the cover film on the photosensitive layer before use, the photosensitive layer can be protected and a photosensitive dry film having excellent pot life can be obtained. As the cover film, those similar to the polymer film used for the support described above can be used, and the cover film and the support may be the same or different materials, and also have a thickness. They may be the same or different.

In order 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 to the substrate is performed. Here, when a photosensitive dry film provided with a cover film is used, the cover film is peeled off to expose the photosensitive layer, and then contact the substrate. Then, the photosensitive layer and the substrate are pressed with a pressure roller or the like for 40 to 40 hours.
The photosensitive layer is laminated on the substrate by thermocompression bonding at about 120 ° C. Then, an exposure step of exposing the photosensitive layer through a negative mask provided with a desired exposure pattern, a step of removing the support from the photosensitive layer, a development step of removing an unexposed portion with a developing solution and developing, By performing a thermosetting step of thermosetting the layer, a printed wiring board having an insulating protective film provided on the surface of the substrate can be manufactured. Further, using such a photosensitive dry film, an insulating resin layer may be formed between layers of the multilayer printed wiring board. It should be noted that the above-mentioned ones can be similarly used as the active light and the developer used for the exposure.

When such a photosensitive composition is used, it has a beautiful appearance and flexibility, is excellent in photosensitivity and developability, and has properties such as heat resistance, electrical insulation, and adhesion to a wiring board. A satisfactory cured film can be formed. This cured film is particularly excellent in flexibility, electrical insulation, and appearance. Therefore, even when used for a thin wiring board such as an FPC board, curling does not occur, and a flexible insulating protective film excellent in electrical performance and handleability can be formed.

[0049]

The present invention will be described in more detail with reference to the following examples. In the following Production Examples 1 to 6, the following <PUA-1 to 6> were synthesized as the urethane (meth) acrylate compound component (A) having a carboxyl group. [Production Example 1] <PUA-1> In a reaction vessel equipped with a stirrer, a thermometer, and a condenser,
Polycaprolactone diol as a polymer polyol (PLACCEL21 manufactured by Daicel Chemical Industries, Ltd.)
2, molecular weight 1250), 3750 g (= 3 mol), dimethylolpropionic acid as a dihydroxyl compound having a carboxyl group, 402 g (= 3 mol), isophorone diisocyanate 15 as a polyisocyanate
54 g (= 7 mol) and 2-hydroxyethyl acrylate as a (meth) acrylate having a hydroxyl group, 238 g (= 2.05 mol), and 1.0 g each of p-methoxyphenol and di-t-butyl-hydroxytoluene I put it in. 60 ° C with stirring
Until heated and stopped, 1.6 g of dibutyltin dilaurate
Was added. When the temperature in the reaction vessel began to decrease, the reaction vessel was heated again, stirring was continued at 80 ° C., and the absorption spectrum of the isocyanate group (2280 cm-
After confirming that 1) had disappeared, the reaction was terminated, and a urethane acrylate compound as a viscous liquid was obtained. The resulting urethane acrylate has an average molecular weight of 25,000 and an acid value of 4
It was 0 mgKOH / g.

[Production Example 2] <PUA-2> 2490 g (= 3 mol) of polycaprolactone diol (PLACCEL208, molecular weight: 830, manufactured by Daicel Chemical Industries, Ltd.) as a polymer polyol, and 402 g of dimethyllol propionic acid as a dihydroxyl compound having a carboxyl group ( = 3 mol) and 1554 g of isophorone diisocyanate as polyisocyanate (= 7 m
ol) and 238 g of 2-hydroxyethyl acrylate as a (meth) acrylate having a hydroxyl group.
Production Example 1 except that each (= 2.05 mol) was used.
<PUA-1>. The average molecular weight of the obtained urethane acrylate was 22,000, and the acid value was 47 mgKOH / g.

[Production Example 3] <PUA-3> Polytetramethylene glycol (PTG-850SN manufactured by Hodogaya Chemical Industry Co., Ltd., molecular weight 8) was used as the polymer polyol.
50) 850 g (= 1 mol), 938 g (= 7 mol) of dimethylolpropionic acid as a dihydroxyl compound having a carboxyl group, and 1998 g (= 9 mol) of isophorone diisocyanate as a polyisocyanate
Was introduced. Heat to 60 ° C with stirring and stop,
1.4 g of dibutyltin dilaurate were added. When the temperature inside the reaction vessel starts to decrease, heat again to 80 ° C.
The stirring was continued while maintaining the temperature at 5 to 85 ° C., and when the concentration of the remaining NCO reached the theoretical value, the reaction was stopped to synthesize a urethane oligomer. Further, 0.9 g each of p-methoxyphenol and di-t-butyl-hydroxytoluene
Then, 238 g (= 2.05 mol) of 2-hydroxyethyl acrylate was added as a (meth) acrylate having a hydroxyl group, and the reaction was restarted. The reaction was terminated after confirming that the absorption spectrum of the isocyanate group (2280 cm ^-1 ) had disappeared by an infrared absorption spectrum, and a urethane acrylate compound as a viscous liquid was obtained. The average molecular weight of the obtained urethane acrylate was 1,6000, and the acid value was 90 mgKOH / g.

Production Example 4 <PUA-4> 148 g of dimethylolbutanoic acid (1.0 m
ol) and 352 g of ε-caprolactone (3.09 mo)
l), and as a catalyst, stannous chloride 5 ppm
The reaction was carried out at 120 ° C. under a nitrogen atmosphere. When the amount of residual ε-caprolactone became 0.5% or less, the reaction was stopped to obtain a polymer polyol. The number average molecular weight of the obtained polymer polyol is 500, and the acid value is 1
It was 10 mgKOH / g. As the polymer polyol, 500 g of the above-mentioned polymer polyol (= 1.0 mo)
l), 444 g (= 2.0 mol) of isophorone diisocyanate as a polyisocyanate and 232 g (= 2.0 mol) of 2-hydroxyethyl acrylate as a (meth) acrylate having a hydroxyl group were used, and 200 ppm of dibutyltin laurate was used. Except having used, it synthesize | combined similarly to <PUA-1> of manufacture example 1. The number average molecular weight of the obtained urethane acrylate was 1,200, and the acid value was 47 mgKOH / g.

Production Example 5 <PUA-5> 2550 g (= 3 mol) of polytetramethylene glycol (PTMG-850, molecular weight 850, manufactured by Hodogaya Chemical Industry Co., Ltd.) as a polymer polyol, and dihydroxyl compound having a carboxyl group as a dihydroxyl compound 670 g (= 5 mol) of methylolpropionic acid, 1776 g (= 8 m) of isophorone diisocyanate as a polyisocyanate
ol) and 238 g of 2-hydroxyethyl acrylate as a (meth) acrylate having a hydroxyl group.
(= 2.05 mol), except that each was used in the same manner as in <PUA-1> of Production Example 1. The number average molecular weight of the obtained urethane acrylate was 22,000, and the acid value was 46 mgKOH / g.

Production Example 6 <PUA-6> As a polymer polyol, a polycarbonate diol containing a unit derived from hexamethylene carbonate and pentamethylene carbonate at a ratio of 1: 1 (molecular weight: 80
0) 800 g (= 1 mol), 938 g (= 7 mol) of dimethylolpropionic acid as a dihydroxyl compound having a carboxyl group, 1998 g (= 9 mol) of isophorone diisocyanate as a polyisocyanate and 2 as a (meth) acrylate having a hydroxyl group 238 g of hydroxyethyl acrylate (= 2.
05 PU) of Production Example 1 except that
-1>. The number average molecular weight of the obtained urethane acrylate is 16,000, and the acid value is 90 mg.
KOH / g.

[Examples 1 to 7, Comparative Examples 1 and 2] The urethane (meth) acrylate compound (A) having a carboxyl group was produced in the above Production Examples 1 to 6 at the compounding ratio (parts by mass) shown in Table 1. <PUA-1 to 6>, a compound (B) having an ethylenically unsaturated group, and a thermosetting resin (C)
, A photopolymerization initiator (D) and a thermal polymerization catalyst (E) were mixed to prepare a photosensitive composition. Examples of the compound (B) having an ethylenically unsaturated group include urethane acrylate,
EB1290K (manufactured by Daicel Chemical Industries Ltd.) and U
F8001 (manufactured by Kyoeisha Chemical Co., Ltd.) was used. As the thermosetting resin (C), bisphenol A type epoxy resin EPICON860 (manufactured by Dainippon Ink and Chemicals, Inc.), biphenyl type epoxy resin YL6121H (manufactured by Yuka Shell Epoxy Co., Ltd.) and cresol novolak type epoxy resin EPICON N660 ( Dainippon Ink and Chemicals, Inc.) was used. As the photopolymerization initiator (D), 2,4,6-trimethylbenzoylphenylphosphine oxide TPO (manufactured by BASF),
4,4'-bis (diethylamino) benzophenone E
AB-F (manufactured by Hodogaya Chemical Co., Ltd.) and aminoacetophenone-based Irgacure 184 (manufactured by Ciba Specialty Chemicals) were used. Melamine PC-1 (manufactured by Nissan Chemical Industries, Ltd.) was used as the thermal polymerization catalyst (E).

[0056]

[Table 1]

[Test Example 1] (Preparation of laminate test piece) Carbitol acetate was added to each of the photosensitive compositions prepared in Examples 1 to 7 and Comparative Examples 1 and 2, and the viscosity was set to 2,0.
The material having a thickness of 00 mPa · s was applied on a substrate for evaluation by screen printing using a 150-mesh polyester plate so that the film thickness after drying was about 30 μm. The applied photosensitive composition was dried at 70 ° C. for 30 minutes to prepare a laminate test piece. The final thickness of the photosensitive layer was 30 ± 2 μm. As the evaluation substrate, the following (1) and (2)
It was used. (1) A printed circuit board (UPISEL (registered trademark) N, manufactured by Ube Industries, Ltd.) composed of a polyimide film (thickness: 50 μm) in which copper foil (thickness: 35 μm) is laminated on one side is washed with a 1% sulfuric acid aqueous solution and washed with water After that, it was dried in a stream of air. (2) 25 μm polyimide film [Kapton (registered trademark) C, manufactured by Toray DuPont Co., Ltd.]

[Exposure, development and heat curing of laminate test pieces] Each of the laminate test pieces obtained above was exposed to an exposure machine having a metal halide lamp [manufactured by Oak Co., Ltd.] HMW-680GW.
Exposure was performed at 500 mJ / cm ² using. Next, 30 ° C
By spraying a 1% by mass aqueous solution of sodium carbonate for 60 seconds, unexposed portions are removed and developed.
A heat treatment for 30 minutes is performed, and a copper-clad laminate (using the evaluation substrate (1)) and a polyimide laminate (the evaluation substrate (2)
Used). In addition, light sensitivity, developability 1 and developability 2
At the time of preparing the evaluation sample, the sample was exposed as a negative pattern using a 21-step Stofa tablet. When preparing a sample for evaluation of solder heat resistance, a 1 cm × 1 cm square and 2 c
A copper foil having a length of 1 mm / 1 mm (line / space) with a length of m remained. Among the PCT resistances, regarding the electrical insulation, IPC (Institut) is used as a negative pattern.
te for Interconnecting and Packaging Electronic Ci
rcuit) standard IPC-C was used. No negative pattern was used when preparing other evaluation samples. Physical property evaluation was performed as follows. Table 2 shows the results. In each of the following evaluations, "flexibility" and "warpage change"
About the polyimide laminate,
Of the T properties, those having a layer (thickness of 30 μm) made of each of the photosensitive compositions of Examples 1 to 7 and Comparative Examples 1 and 2 were provided on a commercially available substrate for electrical insulation. Other evaluations were made on the copper-clad laminate.

[Evaluation Items] Photosensitivity The photosensitivity of the photosensitive composition was evaluated by measuring the number of steps of a step tablet of the photocured film formed on the obtained copper-clad laminate. The light sensitivity is indicated by the number of steps of the step tablet. The higher the number of steps of the step tablet, the higher the light sensitivity. Developability 1 At the time of photosensitivity evaluation, the state of the coating film after developing for 1 minute at a temperature of 30 ° C. and a spray pressure of 2 kg / cm ² using a 1% by mass aqueous solution of sodium carbonate as a developing solution during development is visually observed. Judged. The abbreviations in Table 2 indicate the following. ：: What could be developed △: Some development residue ×: Development residue ・ Developability 2 At the time of development, a 0.5% by mass aqueous solution of sodium carbonate was used as a developing solution at a temperature of 30 ° C. and a spray pressure of 2 kg / cm ² . The state of the coating film after developing for 1 minute under the conditions was visually determined.
The abbreviations in Table 2 indicate the following. ：: What could be developed △: There is some development residue ×: There is development residue ・ Adhesion According to JIS D-0202, a cross cut is made on the copper-clad laminate in a gobang pattern, and then a peeling test using cellophane tape. The state of subsequent peeling was visually determined. ◎: 100/100 with no change observed ○: 100/100 with slight peeling of the wire △: 50/100 to 90/100 ×: 0/100 to 50/100 ・ Flexibility The polyimide laminate was bent at 180 degrees with the cured film composed of the photosensitive layer inside, and the presence or absence of whitening of the cured film was examined. ：: No whitening of the cured film. X: The cured film was whitened. -Warp change A polyimide laminate (30 mm x 30 mm) is used as a test piece, one vertex of the test piece is pressed on a flat surface, and the distance between the vertex at a position diagonal to the vertex and the flat surface is measured. Was measured as the amount of warpage.・ Solder heat resistance In accordance with the test method of JIS C-6481, the copper-clad laminate was floated in a solder bath at 260 ° C. for 10 seconds, and then “swelling” and adhesion of the cured film were comprehensively evaluated. . ◎: no change observed ○: slight change Δ: less than 10% of cured film peeled ×: cured film completely peeled ・ PCT resistance (pressure) Cooker resistance) A container (haft HAST TPC manufactured by Tabai Co., Ltd.) in which a copper-clad laminate is kept at 121 ° C., 2 atm, and 100% relative humidity.
-412-MD) for 100 hours,
Changes in copper foil and insulation resistance test were evaluated. 1) Change in appearance In Table 2, abbreviations indicate the following. ：: No floating, peeling or surface whitening was observed on the cured film composed of the photosensitive layer. Δ: floating, peeling, and whitening of the surface are observed on a part of the cured film composed of the photosensitive layer. X: Floating, peeling, and whitening of the surface are observed on the entire surface of the cured film composed of the photosensitive layer. 2) Changes in copper foil In Table 2, abbreviations indicate the following. ：: No discoloration is observed in the copper foil part. ×: Discoloration is observed in the copper foil part. 3) Electric Insulating Property Each photosensitive composition layer of Examples 1 to 7 and Comparative Examples 1 and 2 was provided on IPC-C (comb pattern) of a commercially available substrate (IPC standard), and according to JIS C5012. 100V
After applying a DC voltage and maintaining the voltage for 1 minute, the insulation resistance value was measured with an electric insulation meter while the voltage was applied.

[Test Example 2] (Preparation of laminate test piece) Methyl cellosolve acetate was added to the photosensitive compositions prepared in Examples 3 and 4 and Comparative Example 2, and the viscosity was 5,000.
The mPa · s was coated on a 23 μm polyethylene terephthalate film using a doctor blade, dried at 80 ° C. for 5 minutes to form a photosensitive layer, and then a 30 μm polyethylene film was laminated thereon. Thus, a photosensitive dry film having a cover film was produced.
The thickness of the photosensitive layer after drying was 30 ± 1 μm. The cover film of this photosensitive dry film was peeled off, and the photosensitive layer was heated to 70 ° C., while the same evaluation substrate used in Test Example 1 was heated to 60 ° C., and the photosensitive layer and the evaluation substrate were heated. And a laminator equipped with a pressure roll. These were also evaluated in the same manner as in Test Example 1. Table 2 shows the results
Shown in

[0061]

[Table 2]

[0062]

As described above, the photosensitive composition of the present invention comprises a urethane (meth) acrylate compound (A) having a carboxyl group and a compound (B) having an ethylenically unsaturated group other than (A). , A thermosetting resin (C), a photopolymerization initiator (D), and a thermopolymerization catalyst (E).
It is possible to form a cured film which is excellent in photosensitivity and developability, and further satisfies properties such as heat resistance, electric insulation, and adhesion to a wiring board. Therefore, it is suitable for use as an insulating protective film on a printed wiring board. Further, since the cured film made of the photosensitive composition of the present invention is particularly excellent in flexibility, no curling occurs even when used on a thin wiring substrate. Therefore, it is most suitable for use on an FPC board.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/004 501 G03F 7/004 501 512 512 H05K 3/28 H05K 3/28 DF term (Reference) 2H025 AA01 AA04 AA10 AA13 AA14 AA20 AB11 AB15 AC01 AD01 BC13 BC42 BC45 BC83 BC85 BC86 BC92 BC93 BJ06 CA00 CB30 CC03 CC11 CC20 DA19 FA17 FA29 4J011 PA85 PA86 PA99 SA01 SA05 SA06 SA07 SA21 SA22 SA23 SA25 SA26 SA31 SA32 SA02 SA31 SA32 SA01 AG13 AG15 AG22 AG23 AG24 AG27 BA07 BA08 BA09 BA10 BA12 BA13 BA15 BA19 BA20 BA24 BA25 BA26 BA27 4J039 AD21 AE04 BE01 BE02 BE12 EA05 5E314 AA25 AA27 AA32 BB02 CC07 CC15 DD06 DD07 FF06 GG03 GG08 GG11 GG26

Claims (27)

[Claims] 1. A photocurable component comprising a urethane (meth) acrylate compound having a carboxyl group (A) and a compound having an ethylenically unsaturated group (B) excluding (A), and a thermosetting resin (C) And a photopolymerization initiator (D) and a thermal polymerization catalyst (E). 2. The urethane (meth) acrylate compound (A) having a carboxyl group has a number average molecular weight of 10
The acid value is from 5 to 150 mg KOH.
/ G. The photosensitive composition according to claim 1, wherein 3. The urethane (meth) acrylate compound (A) having a carboxyl group has an acid value of 5 mgK.
OH / g or more, less than 60 mgKOH / g and 60 mgK
The photosensitive composition according to claim 1, comprising a urethane (meth) acrylate compound (A) having two kinds of carboxyl groups of OH / g or more and 150 mgKOH / g or less. 4. A urethane (meth) acrylate compound (A) having a carboxyl group comprises a unit derived from a (meth) acrylate (a) having a hydroxyl group, a unit derived from a polyol (b), and a polyisocyanate (c). The photosensitive composition according to any one of claims 1 to 3, wherein the photosensitive composition contains a unit derived from (1) as a constituent unit. 5. The polyol (b) is a polymer polyol (b1) and / or a dihydroxyl compound (b)
The photosensitive composition according to claim 4, wherein the polymer polyol (b1) and / or the dihydroxyl compound (b2) has a carboxyl group. 6. The photosensitive composition according to claim 5, wherein the number average molecular weight of the polymer polyol (b1) is from 200 to 2,000. 7. The polymer polyol (b1) is a polycarbonate diol.
Or the photosensitive composition according to 6. 8. The photosensitive composition according to claim 5, wherein the dihydroxyl compound (b2) is dimethylolpropionic acid and / or dimethylolbutanoic acid. 9. The compound according to claim 1, wherein the compound (B) having an ethylenically unsaturated group is a (meth) acrylate and / or glycidyl (meth) acrylate having a hydroxyl group. The photosensitive composition as described in the above. 10. The photosensitive composition according to claim 1, wherein the thermosetting resin (C) is an epoxy resin. 11. A heterogeneous system containing a phase composed of an epoxy resin, which is a bisphenol S type epoxy resin, a diglycidyl phthalate resin, a heterocyclic epoxy resin, a bixylenol type epoxy resin, a biphenyl type epoxy resin. The photosensitive composition according to claim 10, wherein the photosensitive composition is at least one selected from the group consisting of tetraglycidyl xylenoylethane resin. 12. The photosensitive composition according to claim 11, wherein the epoxy resin is a biphenyl type epoxy resin. 13. The photopolymerization initiator (D) is a photocurable component 1
The photosensitive composition according to any one of claims 1 to 12, wherein the photosensitive composition is contained in an amount of 0.1 to 20 parts by mass with respect to 00 parts by mass. 14. The thermal polymerization catalyst (E) is at least one selected from the group consisting of amines, quaternary ammonium salts, acid anhydrides, polyamides, nitrogen-containing heterocyclic compounds, and organometallic compounds. The photosensitive composition according to any one of claims 1 to 13, wherein 15. The photosensitive composition according to claim 1, further comprising an organic solvent. 16. The viscosity is 500 to 500,000 mPa.
The photosensitive composition according to any one of claims 1 to 15, wherein the composition is s. 17. A cured product obtained by curing the photosensitive composition according to claim 1. 18. An ink comprising the photosensitive composition according to claim 15 and a colorant. 19. The viscosity is 500 to 500,000 mPa.
19. The ink according to claim 18, wherein s. 20. The photosensitive composition according to any one of claims 1 to 16 or the ink according to claim 18 or 19, which is applied on a substrate to a thickness of 10 to 100 μm, and then applied at 60 to 100 ° C. After drying in a temperature range of 5 minutes to 30 minutes to a thickness of 5 to 70 μm, after exposure and development,
A method for curing a photosensitive composition, comprising thermally curing. 21. A photosensitive dry film having a photosensitive layer formed from the photosensitive composition according to claim 1 on a support. 22. The photosensitive dry film according to claim 21, wherein the support is a polyester film. 23. A method for producing a photosensitive dry film, comprising a photosensitive layer forming step of applying the photosensitive composition according to claim 1 on a support and drying it. 24. An insulating protective film comprising the photosensitive composition according to claim 1. Description: 25. A printed wiring board comprising the insulating protective film according to claim 24. 26. The printed wiring board according to claim 25, wherein the printed wiring board is a flexible printed wiring board. 27. A laminating step of laminating the photosensitive layer of the photosensitive dry film according to claim 21 or 22 and a substrate, an exposing step of exposing the photosensitive layer, a developing step after the exposing step, A method for manufacturing a printed wiring board, comprising a thermosetting step of thermosetting a layer.