JP2000075484A - Photosensitive resin composition, photosensitive element, photosensitive laminated body and production of flexible printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an alkali developable photosensitive resin compsn. excellent in sensitivity and photosetting property, capable of efficiently forming a pattern by photolithography and excellent also in electric corrosion resistance by incorporating a specified resin, a photopolymerizable compd., a photopolymn. initiator and a specified blocked isocyanate as essential components. SOLUTION: The photosensitive resin compsn. contains a resin having amido bonds, oxyalkylene groups and carboxyl groups, a photopolymerizable compd. having an ethylenically unsatd. group, a photopolymn. initiator and a clocked isocyanate of the formula as essential components. In the formula, each of R1-R3 is 1-12C alkylene or 6-14C arylene and each of R4-R6 is a residue obtd. when an isocyanate reacts with a compd. having active hydrogen. Thus, the alkali development is available.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a photosensitive resin composition, a photosensitive element, a photosensitive laminate, and a method for producing a flexible printed board.

[0002]

2. Description of the Related Art Conventionally, to protect an outer layer circuit of a flexible printed circuit board in which an outer layer circuit is protected, a coverlay which is formed by punching a polyimide film with a die and thermocompression bonding or a cover coat which screen-prints a polyimide resin ink is used. However, in the former case, there is a limit in miniaturization of the punched pattern, so that it cannot be applied to a solder dam between QFP pads with a narrow pitch, and there is also a limit in positional accuracy at the time of bonding, so that there is a large displacement. Since the circuit design in consideration of the degree is required, there is a problem that the FPC cannot be increased in density and reduced in size. In the case of the latter, there is a problem that pattern printing is similarly limited due to screen printing, and workability is poor.

As a method for solving these problems, a photosensitive resin composition comprising various polyamic acids (polyimide precursors), a photocrosslinking agent containing an ethylenically unsaturated group and a photopolymerization initiator is formed on a flexible printed board. A method of forming a coverlay having a fine pattern by exposure, development, and heating is disclosed in JP-A-64-2037 and JP-A-64-2037.
No. 484893, JP-A-5-158237,
It has been proposed in Japanese Patent Application Laid-Open No. 6-298935. However, a sufficient thickness required for the coverlay cannot be ensured from the viewpoint of light transmittance, and a step of heating at a high temperature of 250 ° C. or more is required in order to finally close the polyamic acid to form a polyimide skeleton. Oxidization, deterioration of the adhesive layer, and warpage of the substrate.

A coverlay having a two-layer structure of thermoplastic polyimide and non-thermoplastic polyimide is formed on a flexible printed board by thermocompression bonding, and a resist pattern is formed thereon by screen printing, and the coverlay is patterned by alkali etching. Japanese Patent Application Laid-Open No. 5-183260 discloses a method for laminating a two-layer film of a polyamic acid (polyimide precursor) layer and a photosensitive resin layer on a flexible printed board. First, the photosensitive resin layer is exposed and developed. Japanese Patent Application Laid-Open No. 5-254064 proposes a method in which a photosensitive resin layer is used as an etching resist after a pattern is formed, and then a polyamic acid layer is patterned by alkali etching. However, in the former method, there is a problem in that pattern miniaturization is limited due to screen printing, workability is poor, and there is a problem that the cost is high due to a two-layer structure polyimide film. There is a problem in workability, such as the necessity, two development processes of the photosensitive resin layer and the polyamic acid layer, and finally 250 ° C. or more to finally close the polyamic acid to form a polyimide skeleton. A step of heating at a high temperature is required, and there are problems such as oxidation of the copper circuit, deterioration of the adhesive layer, and warpage of the substrate.

As a developing solution, an inorganic alkaline aqueous solution which does not use a solvent is preferable from the viewpoint of cost and environmental hygiene. However, a developing solution which can be used with the above resin materials is a solvent or a solvent and an alkali. The semi-solvent system, which is a mixture of aqueous solutions, was mostly used.

On the other hand, a method of manufacturing a flexible printed board using an acrylic resin-based photosensitive film as a coverlay, which has been mainly used in the field of printed wiring boards, has been disclosed in Japanese Patent Laid-Open No.
No. 6498, Japanese Patent Application Laid-Open No. 59-230014, and the like. According to this method, a coverlay can be easily formed by the same process as a dry film type permanent mask resist used in the field of a conventional printed wiring board, and it is inexpensive. The compatibility between flexibility and solvent resistance is not sufficient. Japanese Patent Laid-Open Publication No. 6-33 discloses a photosensitive film comprising a combination of an acrylic resin and a specific urethane monomer.
Although proposed in Japanese Patent No. 2171, solvent resistance and electrical reliability are not sufficient. Further, none of the acrylic resin-based photosensitive films has sufficient flame retardancy. Further, at present, a coverlay having satisfactory electric corrosion resistance and cleaning agent resistance while satisfying the folding resistance as a coverlay has not yet been realized.

[0007]

The inventions according to claims 1 and 2 can be alkali-developed, have excellent sensitivity and photocurability, can form a pattern efficiently by photolithography, and have a cured product having folding resistance. The present invention provides a photosensitive resin composition having excellent solder heat resistance, cleaning agent resistance, adhesion and flame retardancy, excellent workability of coating on a film, and excellent electric corrosion resistance. The invention described in claim 3 provides the effect of the invention described in claim 1 or 2, and provides a photosensitive resin composition having more excellent folding resistance and solder heat resistance. The invention according to claim 4 is excellent in sensitivity and photocurability, can form a pattern efficiently by photolithography, and has folding resistance, solder heat resistance, cleaning agent resistance, adhesion, flame retardancy and electrolytic corrosion resistance. The present invention provides a photosensitive element which is excellent in handling, and excellent in workability and workability of lamination on a substrate.

[0008] The invention according to claim 5 is excellent in sensitivity and photocurability, can form a pattern efficiently by photolithography, and has folding resistance, solder heat resistance, cleaning agent resistance, flame retardancy and electrolytic corrosion resistance. Excellent in handling,
An object of the present invention is to provide a photosensitive laminate excellent in workability of manufacturing a flexible printed board. The invention according to claim 6 is extremely excellent in sensitivity and photocurability, can form a pattern efficiently by photolithography, and has folding resistance, solder heat resistance, cleaning agent resistance, adhesion, flame retardancy and electric resistance. An object of the present invention is to provide a photosensitive laminate excellent in food properties, extremely excellent in handleability, and excellent in workability of manufacturing a flexible printed board.

The invention according to claim 7 is excellent in folding resistance, solder heat resistance, cleaning agent resistance, flame retardancy and electric corrosion resistance.
An object of the present invention is to provide a method of manufacturing a flexible printed circuit board capable of manufacturing a flexible printed circuit board excellent in high-density mounting and electrical reliability with good workability and yield. Claim 8
The invention described above provides the effect of the invention described in claim 7 and provides a method for manufacturing a flexible printed board having more excellent solder heat resistance.

[0010]

The present invention comprises (A) a resin having an amide bond, an oxyalkylene group and a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated group, and (C) a photopolymerization initiator. Agent (D) General Formula (I)

Embedded image (Wherein, R ¹ , R ² and R ³ each independently represent a group having 1 to 1 carbon atoms)
2 represents an alkylene group or an arylene group having 6 to 14 carbon atoms, and R ⁴ , R ⁵ and R ⁶ each independently represent a residue obtained when a compound having an active hydrogen is reacted with an isocyanate). A photosensitive resin composition containing the blocked isocyanate as an essential component.

The present invention also relates to a compound (A) comprising (a) a dicarboxylic acid having an oxyalkylene group, (b) a diisocyanate or a diamine, (c) a compound having two or more epoxy groups in one molecule, and (D) The photosensitive resin composition is a resin obtained by reacting a polycarboxylic acid monoanhydride as an essential reaction component.

In the present invention, the resin (A) preferably has a resin content of 20 to 95.
Parts by weight, (B) 5 to 80 parts by weight of the photopolymerizable compound (provided that the total amount of the components (A) and (B) is 100 parts by weight), and (C) 0.01 to 20 parts by weight of the photopolymerization initiator. Parts (based on 100 parts by weight of the total of components (A) and (B)) and (D) 1 to 50 blocked isocyanates.
Parts by weight (the total amount of the components (A) and (B) is 100
(Based on the weight of the photosensitive resin composition).

[0013] The present invention also relates to a photosensitive element having a layer of the photosensitive resin composition and a support film supporting the layer. The present invention also relates to a photosensitive laminate having a layer of the photosensitive resin composition on a surface of a substrate for a flexible printed board. The present invention also relates to a photosensitive laminate having a substrate for a flexible printed board on one surface of the photosensitive resin composition layer and a support film on the other surface. The present invention also provides a flexible printed board, wherein a pattern of a photosensitive resin composition is formed on the surface of a substrate for a flexible printed board by irradiating the photosensitive laminate imagewise with active light and developing the photosensitive laminate. A method for producing the same. Further, the present invention relates to a method for producing the flexible printed board, comprising a step of irradiating active light after development and a step of post-heating.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The photosensitive resin composition of the present invention comprises
(A) a resin having an amide bond, an oxyalkylene group and a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated group, (C) a photopolymerization initiator, and (D) a compound represented by the general formula (I). The blocked isocyanate to be used is an essential component.

In the photosensitive resin composition of the present invention, (A)
The amide bond in the component can be introduced by reacting a dicarboxylic acid having an oxyalkylene group with a diisocyanate or a diamine, and the amide oligomer obtained by this reaction is combined with a compound having two or more epoxy groups in one molecule. When reacted, a compound having a hydroxyl group generated by the reaction between the carboxyl group and the epoxy group of the amide oligomer is obtained. The carboxyl group in the component (A) can be introduced by reacting the compound having a hydroxyl group with a polycarboxylic acid monoanhydride.

In the present invention, for example, (a) a dicarboxylic acid having an oxyalkylene group is reacted with (b) a diisocyanate or a diamine to obtain an amide oligomer, and then (c) two amide oligomers per molecule are used. The above-mentioned compound having an epoxy group is reacted to obtain a compound having a hydroxyl group, and then a polyamide resin obtained by reacting the compound having a hydroxyl group with (d) a polyvalent carboxylic acid monoanhydride is used as a component (A). Can be used.

The (a) dicarboxylic acid having an oxyalkylene group is not particularly limited. For example, (1)
Polyoxyalkylenediamine (the alkylene group has 2 to 6 carbon atoms) [for example, trade name: Jeffamine D-230, D-400, D-2 manufactured by Huntsman Corporation]
000, D-4000 (the alkylene group is an isopropylene group), ED-600, ED-900, ED20
01 (the above alkylene group is an ethylene group and an isopropylene group), EDR-148 (the alkylene group is an ethylene group), α, ω- (3-aminopropyl) -polyethylene glycol manufactured by Koei Chemical Industry Co., Ltd.) And a dicarboxylic acid, and a reaction equivalent ratio (carboxyl group of dicarboxylic acid / amino group of polyoxyalkylenediamine) exceeds 1 to obtain polyoxyalkylenediamide dicarboxylic acid, (2) polyoxyalkylenediamine and tricarboxylic acid Acid monoanhydride [for example, trimellitic anhydride, tricarballylic anhydride, ricinoleic acid dehydrated adduct of maleic anhydride, sorbic acid adduct of maleic anhydride, etc.] with a reaction equivalent ratio (tricarboxylic acid Acid anhydride group of monoanhydride / amino group of polyoxyalkylenediamine) (3) polyoxyalkylenediamine and tetracarboxylic dianhydride [for example, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, s-biphenyltetracarboxylic dianhydride] Anhydrous,
Diphenylsulfonetetracarboxylic dianhydride, methylcyclohexenetetracarboxylic dianhydride, ethylene glycol bisanhydrotrimellitate, etc.) in the reaction equivalent ratio (amino group of polyoxyalkylenediamine / acid of tetracarboxylic dianhydride) The above tricarboxylic acid monoanhydride is reacted with the polyoxyalkylene imide diamine obtained by reacting under conditions where the anhydride group exceeds 1 (an acid anhydride group of tricarboxylic acid monoanhydride / polyoxyalkylene imide diamine). (4) polyoxyalkylene polyimide dicarboxylic acid obtained by reacting amino group) under the condition of 1, and (4) a reaction equivalent ratio of polyoxyalkylene diol (alkylene group having 2 to 14 carbon atoms) and dicarboxylic acid (dicarboxylic acid Of carboxyl group / polyoxyalkylene diol Polyoxyalkylene esters dicarboxylic acid group) is obtained by reacting under conditions of greater than 1, (5) polyoxyethylene diglycolic acid (e.g., Kawaken Fine Chemicals Co., Ltd. trade name PEO acid # 4
00, # 1000, # 4000, etc.).

The dicarboxylic acids in the above (1) and (4) include, for example, aliphatic dicarboxylic acids (succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, dodecane diacid, eicosan diacid) Acid, dimer acid, 1,4-cyclohexanedicarboxylic acid, etc.),
Aromatic dicarboxylic acids (isophthalic acid, terephthalic acid, phthalic acid, 1,5-naphthalenedicarboxylic acid, 4,4'-
Diphenyl ether dicarboxylic acid, 4,4'-diphenyl sulfone dicarboxylic acid, 4,4'-benzophenone dicarboxylic acid, etc.).

Among these, (1) polyoxyalkylene amide dicarboxylic acid, (2) polyoxyalkylene diimide dicarboxylic acid, and (3) polyoxy resin in terms of balance between hydrophilicity and heat resistance of the obtained polyamide resin. Alkylene polyimide carboxylic acids are preferred. These (a) dicarboxylic acids having an oxyalkylene group are used alone or in combination of two or more.

(A) The number of oxyalkylene groups in the dicarboxylic acid having an oxyalkylene group may be one or continuous, and in any case, the total molecular weight of all oxyalkylene groups is as follows: 20
It is preferably from 0 to 10,000, more preferably from 500 to 5,000, and particularly preferably from 1,000 to 3,000. If the molecular weight is less than 200, the hydrophilicity and flexibility of the component (A) obtained tend to decrease, and if it exceeds 10,000, the heat resistance of the component (A) obtained tends to decrease.

Either diisocyanate or diamine (b) may be used, but diisocyanate is preferred from the viewpoint of easy production of component (A). As the diisocyanate, for example, an aromatic diisocyanate (4,
4'-diphenylmethane diisocyanate, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate, p-phenylene diisocyanate, 4,4'-diphenyl ether diisocyanate,
m-xylylene diisocyanate, m-tetramethyl xylylene diisocyanate, etc., aliphatic diisocyanates (hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4
-Trimethylhexamethylene diisocyanate, lysine diisocyanate, etc.), alicyclic diisocyanate (isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate (hydrogenated 4,4'-diphenylmethane diisocyanate), transcyclohexane-
1,4-diisocyanate, hydrogenated m-xylylene diisocyanate, etc.), heterocyclic diisocyanate (3,9
-Bis (3-isocyanatopropyl) -2,4,8,
10-tetraspiro [5,5] undecane, etc.). These are used alone or in combination of two or more.

Examples of the diamine include p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine, 4,4'- (or 3,4'-, 3,3'-, 2,4 '-, 2,2'-) diaminodiphenylmethane, 4,4 '-(or 3,4'
-, 3,3 '-, 2,4'-, 2,2 '-) diaminodiphenyl ether, 4,4'- (or 3,4'-, 3,
3'-, 2,4'-, 2,2'-) diaminodiphenylsulfone, 4,4'- (or 3,4'-, 3,3'-,
2,4 '-, 2,2'-) diaminodiphenyl sulfide, 4,4'-benzophenone diamine, 3,3'-benzophenone diamine, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 4,4'-diaminobenzanilide and the like. These are used alone or in combination of two or more. Aromatic diisocyanates are preferred from the viewpoint of heat resistance of the obtained polyamide resin.

The compound (c) having two or more epoxy groups in one molecule is not particularly limited, and examples thereof include bifunctional aromatic glycidyl ethers (bisphenol A epoxy resin, tetrabromobisphenol A epoxy resin, Bisphenol F epoxy resin, bisphenol AD epoxy resin, naphthalene epoxy resin, biphenyl epoxy resin, tetramethylbiphenyl epoxy resin, etc., polyfunctional aromatic glycidyl ether (phenol novolak epoxy resin, cresol novolak epoxy resin, Dicyclopentadiene-phenol type epoxy resin, tetraphenylolethane type epoxy resin, etc.), bifunctional aliphatic glycidyl ether (polyethylene glycol type epoxy resin, polypropylene glycol type epoxy resin) Fat, neopentyl glycol type epoxy resin, dibromo neopentyl glycol type epoxy resin, hexanediol type epoxy resin, etc.), bifunctional alicyclic glycidyl ether (hydrogenated bisphenol A type epoxy resin, etc.), polyfunctional aliphatic glycidyl ether (Trimethylolpropane type epoxy resin, sorbitol type epoxy resin, glycerin type epoxy resin, etc.), bifunctional aromatic glycidyl ester (phthalic acid diglycidyl ester, etc.), bifunctional alicyclic glycidyl ester (tetrahydrophthalic acid diglycidyl ester, Hexahydrophthalic acid diglycidyl ester, etc.), bifunctional aromatic glycidylamine (N, N-diglycidylaniline, N, N-diglycidyltrifluoromethylaniline, etc.), polyfunctional aromatic glycidylamine (N, N, N , N'- tetraglycidyl-4,4'-diaminodiphenylmethane, 1,
3-bis (N, N-glycidylaminomethyl) cyclohexane, N, N, O-triglycidyl-p-aminophenol, etc., bifunctional alicyclic epoxy resin (alicyclic diepoxy acetal, alicyclic diepoxy) Adipate, alicyclic diepoxy carboxylate, vinylcyclohexene dioxide, etc.) bifunctional heterocyclic epoxy resin (diglycidyl hydantoin, etc.),
Examples include a polyfunctional heterocyclic epoxy resin (such as triglycidyl isocyanurate) and a bifunctional or polyfunctional silicon-containing epoxy resin (such as an organopolysiloxane type epoxy resin).

Of these, bifunctional epoxy resins are preferred in terms of easy control of the reaction for producing the hydrophilic polyamide resin, and among the bifunctional epoxy resins, the heat resistance of the resulting hydrophilic polyamide resin is preferred. In view of the above, bifunctional aromatic glycidyl ether is more preferable, and among them, bisphenol A type is preferable in terms of availability, low cost, and the like. Bisphenol F in terms of improvement
Type epoxy resins are particularly preferred. These are used alone or in combination of two or more.

The above (d) polyhydric carboxylic acid monoanhydride is not particularly restricted but includes, for example, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride and hexahydrophthalic anhydride. Anhydride, methyl hexahydrophthalic anhydride, nadic anhydride, methyl nadic anhydride, methyl 2-substituted butenyltetrahydrophthalic anhydride, itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenyl succinic anhydride Anhydride, maleic anhydride, maleic anhydride adduct of methylcyclopentadiene, alkylated endoalkylenetetrahydrophthalic anhydride, phthalic anhydride, chlorendic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride , Tricarballylic anhydride, maleic anhydride Linoleic acid dehydration product adduct,
Sorbic acid adduct of maleic anhydride, trimellitic anhydride and the like, among which, among others, reactivity, reaction yield,
Tetrahydrophthalic anhydride is preferred in terms of low cost and the like. These are used alone or in combination of two or more.

The reaction equivalent ratio of (a) a dicarboxylic acid having an oxyalkylene group to (b) a diisocyanate or a diamine (a carboxyl group in (a) / an isocyanate group or amino group in (b)) is 1.03 to 2. It is preferably 1.05 to 1.7, more preferably 1.1 to 1.7.
5 is particularly preferred. When the reaction equivalent ratio is less than 1.03, the resulting amide oligomer is likely to have both ends having no carboxyl group, which makes it difficult to react with the next compound (c) having two or more epoxy groups in one molecule. When the reaction equivalent ratio exceeds 2, the (a) dicarboxylic acid having an oxyalkylene group tends to remain as an unreacted substance, and the heat resistance of the finally obtained component (A) tends to decrease. is there.

The reaction between the components (a) and (b) can be carried out in an organic solvent. The organic solvent is not particularly limited, and examples thereof include lactones (γ-butyrolactone, γ-
Caprolactone), carbonates (ethylene carbonate, propylene carbonate, etc.), ketones (methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), esters (ethyl acetate, n-butyl acetate, etc.), glymes (diglyme, triglyme, tetraglyme) ), Hydrocarbons (toluene, xylene, cyclohexane, etc.), amides (N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, etc.), ureas (N, N-dimethyl) Ethylene urea, N, N-dimethylpropylene urea, tetramethyl urea, etc.), sulfones (sulfolane, etc.) and the like. Among them, lactones are mainly used.
(A) It is preferable in that the composition containing the resin as the component (A) is excellent in low-temperature drying property when the composition is heated to form a film.

The amount of the organic solvent used depends on the amount of component (a) and (b)
The amount is preferably from 30 to 2,000 parts by weight, more preferably from 50 to 1,000 parts by weight, particularly preferably from 70 to 400 parts by weight, based on 100 parts by weight of the total amount of the components. If the amount of the organic solvent used is less than 30 parts by weight, the solubility is poor, and the reaction system tends to become non-uniform or highly viscous. The reaction tends to be difficult to complete. These organic solvents are used alone or in combination of two or more.

The reaction temperature of the component (a) and the component (b) is 1
The temperature is preferably from 00 to 300 ° C, more preferably from 150 to 270 ° C, and particularly preferably from 170 to 250 ° C. When the reaction temperature is lower than 100 ° C., the reaction does not easily proceed and the reaction tends to be difficult to be completed.

When the amide oligomer is obtained by reacting the components (a) and (b), a part of the dicarboxylic acid having an oxyalkylene group (a) is converted into a dicarboxylic acid containing no (a ') oxyalkylene group. Can be replaced.
The (a ') dicarboxylic acid containing no oxyalkylene group is not particularly limited, and the compounds exemplified as the dicarboxylic acids in the above (1) and (4) can be used. The dicarboxylic acid having a carbonate diol bond can be synthesized by reacting polycarbonate diol and dicarboxylic acid under the condition that the equivalent ratio (carboxyl group of dicarboxylic acid / hydroxyl group of polycarbonate diol) exceeds 1.

When (a ') a dicarboxylic acid containing no oxyalkylene group is used, the amount of the dicarboxylic acid to be used is 5 to 90 parts with respect to 100 weight of the total of the components (a) and (a').
Parts by weight are preferred, 10 to 70 parts by weight are more preferred,
Particularly preferred is 20 to 50 parts by weight. When the use amount of the component (a ') exceeds 90 parts by weight, the hydrophilicity of the obtained component (A) decreases, and when used as a binder component of the photosensitive resin composition, the content of the photosensitive resin composition is reduced. The alkali developability tends to decrease, and the flexibility tends to decrease. These (a ') dicarboxylic acids containing no oxyalkylene group can be used alone or in combination of two or more.

In the step (c) of reacting two or more epoxy groups in one molecule with an amide oligomer obtained by reacting the components (a) and (b) to obtain a compound having a hydroxyl group, (C) The reaction equivalent ratio of the compound having two or more epoxy groups in one molecule (epoxy group of (c) / carboxyl group of amide oligomer) is 0.5.
To 3, preferably 1.1 to 2.5, more preferably 1.
2 to 2.0 is particularly preferred. When the reaction equivalent ratio is less than 0.5, it is difficult to increase the molecular weight, and the final product (A) is obtained.
The heat resistance and flexibility of the component resin tend to decrease, and when the reaction equivalent ratio exceeds 3, gelation and the like due to side reactions tend to occur, the reaction tends to be difficult to control, and the bridge density decreases. And the flexibility of the resin (A) tends to decrease.

The reaction between the amide oligomer and the component (c) in the step of obtaining the compound having a hydroxyl group can be carried out in an organic solvent subsequent to the step of obtaining the amide oligomer. The organic solvent is not particularly limited, and for example, the organic solvent used in the step of obtaining the amide oligomer described above can be used as it is. In the step of obtaining the amide oligomer, when a lactone is used as a main component, amides, especially low boiling points, are used in view of the solubility and low-temperature drying property of the finally obtained component (A) resin. Is preferably used in combination with N, N-dimethylformamide.

The amount of the organic solvent used is 30 to 20 parts by weight based on 100 parts by weight of the total amount of the amide oligomer and the component (c).
00 parts by weight is preferable, 50 to 1000 parts by weight is more preferable, and 70 to 400 parts by weight is particularly preferable. If the amount of the organic solvent used is less than 30 parts by weight, the solubility is poor, and the reaction system tends to be non-uniform or highly viscous,
When the amount of the organic solvent exceeds 2000 parts by weight, the reaction does not easily proceed, and the reaction tends to be difficult to complete. These organic solvents are used alone or in combination of two or more.

The reaction temperature between the amide oligomer and the component (c) in the step of obtaining the compound having a hydroxyl group is 50 to 25.
0 ° C. is preferable, 100 to 200 ° C. is more preferable, and 1 ° C.
20-180 ° C is particularly preferred. The reaction temperature is 50 ° C
When the reaction temperature is less than 250 ° C., gelation or the like due to a side reaction tends to occur and the reaction tends to be difficult to control.

The compound having a hydroxyl group may have an epoxy group at the terminal. In this case, after obtaining the compound having the hydroxyl group, the compound having the hydroxyl group is removed in order to eliminate the epoxy group of the compound having the hydroxyl group. Can be reacted with a monocarboxylic acid. The monocarboxylic acid is not particularly limited, and includes, for example, a photopolymerizable unsaturated group-containing aliphatic monocarboxylic acid (methacrylic acid, acrylic acid, etc.),
Examples include aliphatic monocarboxylic acids (such as formic acid, acetic acid, propionic acid, butyric acid, and hexanoic acid) and aromatic monocarboxylic acids (such as benzoic acid and diphenylacetic acid). Among these, a photopolymerizable unsaturated group-containing aliphatic monocarboxylic acid is preferred because it can impart photocurability to the finally obtained resin of the component (A). These monocarboxylic acids can be used alone or in combination of two or more.

When a monocarboxylic acid is reacted with a compound having a hydroxyl group, the reaction equivalent ratio of the compound having a hydroxyl group to the monocarboxylic acid (carboxyl group of the monocarboxylic acid / epoxy group in the compound having the hydroxyl group) is 0.5. To 5, preferably 0.8 to 2, more preferably 1 to 1.2. If the reaction equivalent ratio is less than 0.5, unreacted epoxy groups remain, and the storage stability of the resin of component (A) tends to decrease. If the reaction equivalent ratio exceeds 5, unreacted monocarboxylic acid Tend to remain in large quantities and increase skin irritation.

In the step (d) of reacting the compound having a hydroxyl group with the polyhydric carboxylic acid monoanhydride to obtain a polyamide resin, the reaction equivalent ratio of the compound having a hydroxyl group and (d) the polyhydric carboxylic acid monoanhydride is used. ((D) the acid anhydride group / hydroxyl group of the compound having a hydroxyl group) is 0.1 to 1.5.
Is preferably, more preferably 0.3 to 1,
It is particularly preferred to be 0.6 to 0.9. When the reaction equivalent ratio is less than 0.1, the obtained polyamide resin has poor solubility in an aqueous alkali solution, and when used as a polymer component of the photosensitive resin composition, the alkali developability of the photosensitive resin composition is reduced. When the reaction equivalent ratio exceeds 1.5, a large amount of the polyhydric carboxylic acid monoanhydride (d) tends to remain as an unreacted substance, and the storage stability of the polyamide resin tends to decrease.

The reaction between the compound having a hydroxyl group and the component (d) can be carried out in an organic solvent subsequent to the step of obtaining the compound having a hydroxyl group. The organic solvent is not particularly limited, and for example, the organic solvent used in the step of obtaining the amide oligomer described above can be used as it is. In the step of obtaining a compound having a hydroxyl group, when a mixed solvent composed of a lactone and an amide is mainly used, it is not necessary to use an additional organic solvent.

The amount of the organic solvent used is 30 to 2 parts by weight based on 100 parts by weight of the total of the compound having a hydroxyl group and the component (d).
000 parts by weight is preferred, 50 to 1000 parts by weight is more preferred, and 70 to 400 parts by weight is particularly preferred. If the amount of the organic solvent used is less than 30 parts by weight, the solubility is poor,
The reaction system tends to be non-uniform or highly viscous. If the amount of the organic solvent exceeds 2000 parts by weight, the reaction does not easily proceed and the reaction tends to be difficult to complete. These organic solvents are used alone or in combination of two or more.

The reaction temperature between the compound having a hydroxyl group and the component (d) is preferably from 40 to 250 ° C, more preferably from 60 to 200 ° C, particularly preferably from 80 to 180 ° C. If the reaction temperature is lower than 40 ° C., the reaction does not easily proceed and the reaction tends to be difficult to complete. If the reaction temperature exceeds 250 ° C., gelation or the like due to side reactions tends to occur, and the reaction tends to be difficult to control.

After obtaining the compound having a hydroxyl group and / or obtaining the polyamide resin, the compound having a hydroxyl group and / or the polyamide resin contains a photopolymerizable unsaturated group for the purpose of imparting photocurability to the polyamide resin. The aliphatic monoisocyanate can be reacted, and the product obtained in this manner can be used as the component (A).

The photopolymerizable unsaturated group-containing aliphatic monoisocyanate is not particularly limited, and includes, for example, 2-isocyanateethyl methacrylate, methacryloyl isocyanate and the like. These may be used alone or in combination of two or more. be able to.

When a photopolymerizable unsaturated group-containing aliphatic monoisocyanate is used, the reaction equivalent ratio of the hydroxyl group-containing compound and / or the polyamide resin to the photopolymerizable unsaturated group-containing aliphatic monoisocyanate (photopolymerizable unsaturated group) The isocyanate group of the containing aliphatic monoisocyanate / the compound having a hydroxyl group and / or the hydroxyl group of the polyamide resin)
0.05 to 1.5 is preferable, 0.1 to 1 is more preferable, and 0.1 to 0.4 is particularly preferable. When the reaction equivalent ratio is less than 0.05, photocurability is low, and when used as a polymer component of the photosensitive resin composition, the sensitivity of the photosensitive resin composition tends to decrease. If it exceeds 0.5, the photopolymerizable unsaturated group-containing aliphatic monoisocyanate tends to remain as an unreacted product, and storage stability tends to decrease. In each of the above-mentioned reactions, a known reaction catalyst suitable for the reaction is used, if necessary.

The resin as the component (A) obtained as described above has, for example, a chemical structure represented by the following general formula (II).

Embedded image (Wherein R ⁷ is a residue remaining after removing two carboxyl groups from a dicarboxylic acid having an oxyalkylene group)
R ⁸ represents a diamine residue or a diisocyanate residue; R ⁹ represents a divalent residue remaining after removing two epoxy groups from a compound having two or more epoxy groups in one molecule. R ¹⁰ represents a hydrogen atom,

Embedded image (Where R ¹¹ represents a residue of a polycarboxylic acid monoanhydride) or

Embedded image (However, R ¹² represents an alkylene group having 1 to 6 carbon atoms or a single bond, R ¹³ represents a hydrogen atom or a methyl group), and n and m each independently represent an integer of 1 to 100 )

The chemical structure represented by the general formula (II) shows the chemical structure of the portion excluding the terminal of the resin, but when the terminal is considered, the chemical structure is as follows.

[0047]

Embedded image (Wherein, the definitions of R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , m and n are the same as in the general formula (II))

The resin represented by the general formula (II-1) has epoxy groups at both ends and has a general formula (II-2)
Is a resin having an epoxy group at one terminal and a carboxyl group at the other terminal, and the resin represented by the general formula (II-3) has a carboxyl group at both terminals. The terminal epoxy groups of these resins may be modified by reacting a part or all of them with a monocarboxylic acid such as methacrylic acid, acrylic acid, acetic acid or propionic acid. Usually, the resin to be produced is a mixture containing these resins, but from the viewpoint of heat resistance, pot life, etc., the resin represented by (II-1) or the epoxy group at the terminal of the resin has a monocarboxylic acid. It is preferable that the resin modified by the reaction with an acid is contained in an amount of 20% by weight or more, and this can be performed by adjusting the use ratio of each component used in the production of the resin.

The weight average molecular weight of the component (A) (measured by GPC, lithium bromide monohydrate and phosphoric acid were used as buffers so that the concentrations were 0.03 mol / l and 0.06 mol / l, respectively). Prepared dimethylformamide (D
(Calculated as a polystyrene equivalent value from a calibration curve prepared using standard polystyrene using an eluent of an equal volume mixed solvent of MF) and tetrahydrofuran (THF).
However, from the viewpoints of tack, solder heat resistance, solvent resistance, folding resistance, adhesion, coating workability, etc.
0, preferably 20,000 to 200,00.
0, more preferably 30,000-100,
Particularly preferred is 000.

The photopolymerizable unsaturated compound having an ethylenically unsaturated group used as the component (B) in the photosensitive resin composition of the present invention is not particularly limited, and known compounds can be used. Acrylate or methacrylate of alcohol (diethylene glycol dimethacrylate,
Tetraethylene glycol diacrylate, hexapropylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, 1,6-hexanediol diacrylate,
1,9-nonanediol diacrylate, dipentaerythritol pentaacrylate, trimethylolpropane trimethacrylate, etc., epoxy acrylate compounds (2,2-bis (4-methacryloxypentaethoxyphenyl) propane, 2,2-bis (4 -Acryloxypentaethoxyphenyl) propane, bisphenol A, an acrylic acid or methacrylic acid adduct of an epichlorohydrin epoxy resin, an acrylate or methacrylate having a benzene ring in the molecule (phthalic anhydride-
Low-molecular unsaturated polyesters such as a condensate of neopentyl glycol-acrylic acid in a molar ratio of 1: 2: 2, etc.), adduct of trimethylolpropane triglycidyl ether with acrylic acid or methacrylic acid, trimethylhexamethylene diisocyanate and 2 A urethane acrylate compound or a urethane methacrylate compound obtained by reacting a monohydric alcohol with an acrylic acid monoester or a methacrylic acid monoester, methoxypolyethylene glycol acrylate, methoxypolyethylene glycol methacrylate, methoxypolypropylene glycol acrylate,
Methoxy polypropylene glycol methacrylate, phenoxy polyethylene glycol acrylate, phenoxy polyethylene glycol methacrylate, phenoxy polypropylene glycol acrylate, phenoxy polypropylene glycol methacrylate, nonylphenoxy polyethylene glycol acrylate, nonylphenoxy polyethylene glycol methacrylate, nonylphenoxy polypropylene glycol acrylate,
Nonylphenoxy polypropylene glycol methacrylate and the like can be mentioned.

In terms of folding resistance and electrical reliability as a coverlay, bisphenol A polyoxyethylene dimethacrylate, tetrafunctional phthalic anhydride adduct of hexafunctional bisphenol F epoxy acrylate, and bifunctional bisphenol F epoxy acrylate Tetrahydrophthalic anhydride adduct is preferred. These compounds can be used alone or in combination of two or more.

Further, a carboxyl group-containing epoxy (meth) acrylate compound represented by the following general formula (III) can also be used.

[0053]

Embedded image (Wherein, R ¹⁴ , R ¹⁵ and R ¹⁶ each independently represent a hydrogen atom or a methyl group, and R ¹⁷ and R ¹⁸ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a halogen atom. And a plurality of R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different, and R ¹⁹ is maleic acid;
Monovalent groups remaining after removing one carboxyl group from tetrahydrophthalic anhydride, succinic acid or

Embedded image (However, R ¹⁶ is a hydrogen atom or a methyl group, R ²⁰
Represents a monovalent group remaining after removing one carboxyl group from maleic acid, tetrahydrophthalic anhydride, and succinic acid), and m is an integer of 1 to 100)

Examples of such carboxyl group-containing epoxy (meth) acrylate compounds include hexafunctional bisphenol F type epoxy acrylate anhydride adducts (trade name: ZFR-1201, manufactured by Nippon Kayaku Co., Ltd.), Functional bisphenol F type epoxy acrylate anhydride adducts (trade name: ZFR-1211 manufactured by Nippon Kayaku Co., Ltd.) and the like.

The photopolymerization initiator used as the component (C) in the photosensitive resin composition of the present invention is not particularly limited, and known photopolymerization initiators can be used. Bis (dimethylamino) benzophenone (Michler's ketone), 4,4'-bis (diethylamino) benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl)- Butanone-
1,2-ethylanthraquinone, phenanthrenequinone, etc.), benzoin ether (benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, etc.), benzoin (methyl benzoin, ethyl benzoin, etc.), benzyl derivative (benzyl dimethyl ketal, etc.), 2, 4,5-triarylimidazole dimer (2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl)-
4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-phenylimidazole dimer, 2- (o-methoxyphenyl)-
4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer, -(2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer and the like, and acridine derivatives (9-phenylacridine,
1,7-bis (9,9'-acridinyl) heptane and the like), N-phenylglycine and the like. These are used alone or in combination of two or more.

The blocked isocyanate represented by the general formula (I) used as the component (D) in the photosensitive resin composition of the present invention is obtained by reacting a compound having an active hydrogen (blocking agent) with a polyisocyanate compound. It is a stable compound at room temperature.

In the general formula (I), R ¹ , R ² and R ³
Examples of the alkylene group having 1 to 12 carbon atoms include a methylene group, an ethylene group, a propylene group, an isopropylene group, a butylene group, an isobutylene group, a t-butylene group, a pentylene group, a neopentylene group, a hexylene group,
Examples include a heptylene group, an octylene group, a 2-ethylhexylene group, a nonylene group, a decylene group, an undecylene group, and a dodecylene group. Further, the alkylene group having 1 to 12 carbon atoms may contain an alicyclic ring, and may be substituted with a halogen atom such as fluorine, chlorine, bromine and iodine. Further, carbon atoms in R ^1, R ² and R ³ having 6 to 14
Examples of the arylene group include a phenylene group, a tolylene group,
Examples include a naphthylene group and a diethylnaphthylene group.
Further, the arylene group having 6 to 14 carbon atoms may be substituted with a halogen atom such as fluorine, chlorine, bromine and iodine. Examples of the compound having an active hydrogen (blocking agent) include oximes such as dimethyl oxime, diethyl oxime and methyl ethyl oxime, β-diketones such as acetylacetone and benzoylacetone, phenols, alkanols, and ε-caprolactam. Can be

As the blocked isocyanate represented by the general formula (I), Sumidur BL3175 (in the general formula (I), R ¹ , R ² and R ³ are all hexylene groups,
A compound in which R ⁴ , R ⁵ and R ⁶ are groups obtained by removing a hydrogen atom from a hydroxyl group of methyl ethyl oxime; a compound having active hydrogen (blocking agent is methyl ethyl oxime); Sumidur CTstable (general formula (I) And R ¹ ,
Compounds in which R ² and R ³ are all tolylene groups, and R ⁴ , R ⁵ and R ⁶ are groups in which a hydrogen atom has been removed from a hydroxyl group of phenols; compounds having active hydrogen (blocking agents) are phenols); Joule TPLS-270
4 (in the formula (I), R ¹ , R ² and R ³ are groups in which two isocyanate groups are removed from isophorone diisocyanate, and R ⁴ , R ⁵ and R ⁶ are groups in which a hydrogen atom is removed from ε-caprolactam) A compound having active hydrogen (blocking agent is ε-caprolactam) (all manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name) and the like are commercially available.

(A) in the photosensitive resin composition of the present invention
The amount of the components is such that the total amount of the components (A) and (B) is 1
As 00 parts by weight, it is preferably 20 to 95 parts by weight, more preferably 30 to 90 parts by weight, and 4 parts by weight.
It is particularly preferred that the amount be 0 to 90 parts by weight. If the amount is less than 20 parts by weight, the film formability of the photosensitive element tends to decrease. When a cover lay is formed by thermocompression bonding on the surface on which is formed, circuit coverage and solder heat resistance tend to decrease.

(B) in the photosensitive resin composition of the present invention
The amount of the components is such that the total amount of the components (A) and (B) is 1
The amount of 00 parts by weight is preferably from 5 to 80 parts by weight, more preferably from 10 to 70 parts by weight. If the compounding amount is less than 5 parts by weight, the sensitivity as a photosensitive resin composition is low, and the circuit coverage is reduced when the photosensitive element is formed into a coverlay by thermocompression bonding to a surface of a flexible printed board on which wiring is formed. When the content exceeds 80 parts by weight, the photosensitive element tends to exude from the side due to the flow of the photosensitive layer when formed into a photosensitive element, and storage stability tends to decrease.

(C) in the photosensitive resin composition of the present invention
The blending amount of the components is 10% in total of the components (A) and (B).
It is preferably 0.01 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, based on 0 parts by weight. If the amount is less than 0.01 part by weight, it is difficult to obtain sufficient sensitivity. If the amount is more than 20 parts by weight, light absorption on the exposed surface of the photosensitive resin composition increases and photocuring inside is insufficient. Tend to be.

(D) in the photosensitive resin composition of the present invention
The blending amount of the components is 10% in total of the components (A) and (B).
The amount is preferably 1 to 50 parts by weight, more preferably 1 to 40 parts by weight, based on 0 parts by weight. If the amount is less than 1 part by weight, sufficient detergent resistance tends not to be obtained, and if it exceeds 50 parts by weight, the sensitivity of the photosensitive resin composition tends to decrease.

The photosensitive resin composition of the present invention may further contain (E) a hydroxyl group-containing phosphorus compound as a flame retardant. (E) The hydroxyl group-containing phosphorus compound is not particularly limited and a known compound can be used, and examples thereof include the following compounds. These are used alone or in combination of two or more.

[0064]

Embedded image

When the component (E) is added to the photosensitive resin composition of the present invention, the amount of the component (E) is 1 to 100 parts by weight of the total amount of the components (A) and (B). It is preferably 50 parts by weight or less, more preferably 10 to 40 parts by weight. If the amount is less than 1 part by weight,
There is a tendency that sufficient flame retardancy cannot be obtained, and if it exceeds 50 parts by weight, the sensitivity of the photosensitive resin composition tends to decrease.

In addition to the component (E), other flame retardants such as FG-700 manufactured by Teijin Chemicals Ltd.
0, FG-7500, FG-8100, FG-360
0, FG-3200, FG-3100, FG-300
0, FG-2000, product name TAIC-6 manufactured by Nippon Kasei
B, etc., halogenated phosphoric acid esters such as CR-380, CR-509, CR-900 manufactured by Daihachi Chemical Industry Co., Ltd., Fosflex 580, manufactured by Akzo Kashima Co., Ltd. Flex 112, Fosflex 574, product name CR7 manufactured by Daihachi Chemical Industry Co., Ltd.
33S, CR741, CR747, PX200, PX2
A flame retardant such as an aromatic phosphate ester compound such as 01 or PX202 can also be used. Also, antimony trioxide, antimony pentoxide, barium borate, Showa Denko
A flame-retardant aid such as aluminum hydroxide such as Heidilite H42-STV (trade name) manufactured by Co., Ltd. can also be added.

When other flame retardants are used, the amount is from 1 to 50 parts by weight based on 100 parts by weight of the total of the components (A), (B), (C) and (D). Is preferred. When the flame retardant aid is used, the compounding amounts are as follows: component (A), component (B), component (C) and component (D).
The amount is preferably 1 to 80 parts by weight based on 100 parts by weight of the total amount of the components. If the amount is less than 1 part by weight, the effect of improving flame retardancy tends to be small, and if it exceeds 80 parts by weight, photocurability, heat resistance, solvent resistance, and the like tend to decrease.

Further, polyvinylpyrrolidone may be added to the photosensitive resin composition of the present invention for the purpose of reducing tack and edge phasing. Examples of such polyvinylpyrrolidone include polyvinylpyrrolidone K120, K90, K30 and the like manufactured by ISP. The weight average molecular weight of polyvinylpyrrolidone is 1
It is preferably from 000 to 3,000,000.

When polyvinylpyrrolidone is used, the amount of component (A), component (B), component (C) and component (D)
The amount is preferably 1 to 20 parts by weight based on 100 parts by weight of the total amount of the components. If the amount is less than 1 part by weight, the effect of reducing tack and edge phasing tends to be small, and if it exceeds 20 parts by weight, heat resistance tends to decrease.

Further, a plasticizer may be added to the photosensitive resin composition of the present invention. The plasticizer used is not particularly limited and includes, for example, p-toluenesulfonamide,
Toluenesulfone-N-ethylamide, p-toluenesulfone-N-cyclohexylamide, phthalic acid di (2-
Ethylhexyl), dibutyl phthalate, dinonyl phthalate, di (2-ethylhexyl) adipate, dibutyl adipate, di (2-ethylhexyl) sebacate, dibutyl sebacate, tributyl acetylcitrate, azelaic acid (2-ethylhexyl), Dibutyl azelate, triphenyl phosphate, tricresyl phosphate, diethylene glycol monolate, epoxy fatty acid ester,
Examples include methoxychlorinated methyl stearate, tri (2-ethylhexyl) trimellitate, and trialkyl trimellitate. Among them, p is preferable in terms of compatibility with the resist shape, the resin (A) component, polyvinylpyrrolidone, and the like.
-Toluenesulfonamide is preferred.

When a plasticizer is used, the compounding amount is (A)
Component 1, total amount of component (B), component (C) and component (D) 1
Preferably, the amount is 1 to 20 parts by weight based on 00 parts by weight. If the amount is less than 1 part by weight, the effect of imparting flexibility tends to be small, and if it exceeds 20 parts by weight, heat resistance tends to decrease.

It is preferable to add a thermal crosslinking agent to the photosensitive resin composition of the present invention from the viewpoint of improving solvent resistance and the like.
Examples of the thermal crosslinking agent include a melamine compound and a bismaleimide compound. As the melamine compound, melamine manufactured by American Cyanamid Co., Ltd. or Mitsui Cytec Co., Ltd., for example, Cymel (registered trademark) 300, 301, 303, 350, 370, 38
0, 1116 and 1130, Cymel (registered trademark) 11
Benzoguanamines such as 23 and 1125, the glycoluril resins Cymel® 1170, 1171 and 1172, and urea-based resin Beetle® 60, 65 and 80.

Further, as the bismaleimide compound,
2,2-bis (p-maleimidylphenoxyphenyl)
And propane (trade name: BBMI, manufactured by Hitachi Chemical Co., Ltd.). Further, in order to accelerate the thermosetting reaction of the bismaleimide compound, a peroxide (for example, Perhexa B25 (2,5-dimethyl-2,5-di-t-
A reaction catalyst such as -butylperoxyhexene-3)) may be used in combination.

When using a thermal crosslinking agent, the compounding amount is as follows:
The amount is preferably 1 to 30 parts by weight based on 100 parts by weight of the total of the components (A), (B), (C) and (D). If the amount is less than 1 part by weight, the effect of improving solvent resistance tends to be small, and if it exceeds 30 parts by weight, photocurability, thermal stability, and the like tend to decrease.

The photosensitive resin composition of the present invention may contain a dye, a color former, a pigment, a stabilizer, an adhesion-imparting agent, and the like, if necessary. Preferred dyes include monoazo dyes such as Malachite Green, Victoria Pure Blue, and UV blue 236 manufactured by Mitsui Chemicals, Inc. Preferred adhesion promoters include 3
-Mercapto-1H-1,2,4-triazole, 2-
Amino-1,3,4-thiazole-5-thiol, 1H
-Tetrazole, and 5,5'-bis-1H-tetrazole. These amounts are (A)
Component 1, total amount of component (B), component (C) and component (D) 1
It is preferably 0.5 to 5 parts by weight with respect to 00 parts by weight.

The photosensitive resin composition of the present invention comprises the above (A)
A solvent capable of dissolving the components, (B), (C) and (D), for example, toluene, acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl cellosolve,
A uniform solution can be obtained by dissolving and mixing in ethyl cellosolve, γ-butyl lactone, N-methylpyrrolidone, dimethylformamide, tetramethyl sulfone, diethylene glycol dimethyl ether, chloroform, methylene chloride, methyl alcohol, ethyl alcohol, etc. .

The photosensitive resin composition of the present invention is prepared as a liquid coating composition by screen printing, flow coating, roller coating, slot coating, spin coating, curtain coating, spray coating, dipping as a liquid coating composition as described above. It can be applied on a substrate or a support using a general method including coating. At this time, the viscosity of the liquid coating composition can be adjusted by using a solvent, a thickener, a filler, and the like as necessary so as to satisfy the requirements of each application method. After coating on a substrate or a support, the liquid coating layer is dried to remove the solvent.

The photosensitive resin composition of the present invention can be coated on a support and dried to obtain a photosensitive element.
As the support, a polymer film, for example, a film made of polyethylene terephthalate, polypropylene, polyethylene or the like is used, and among these, polyethylene terephthalate is preferable. Because these polymer films must later be removable from the photosensitive layer,
It must not be surface-treated or made of any material that cannot be removed. The thickness of these polymer films is usually 5 to 100 μm, preferably 10 to 30 μm. One of these polymer films may be laminated on both sides of the photosensitive layer as a support film for the photosensitive layer and the other as a protective film for the photosensitive layer. Further, the photosensitive resin composition of the present invention is coated on a support as described above and dried to form a photosensitive layer, and a flexible printed board having wiring formed on the photosensitive layer is pressed to obtain a laminate. You can also. Further, the laminate of the present invention can be wound into a roll and stored.

In producing a photoresist image using the photosensitive element of the present invention, if the above-mentioned protective film is present, after removing the protective film, the photosensitive layer is pressed against the substrate while heating. It is laminated by doing. When manufacturing a flexible printed board, the surface to be laminated is usually a flexible printed board on which wiring is formed by etching or the like, but there is no particular limitation. The thermocompression bonding of the photosensitive layer is usually performed at a temperature of 90 to 130 ° C. and a compression pressure of 3.0 × 10 ⁵ Pa. In order to further improve the followability of the photosensitive layer to the flexible printed board, 4 × 10 5 It is preferable to perform thermocompression bonding under the above conditions under reduced pressure of ³ Pa or less. When thermocompression bonding is performed under reduced pressure, it is preferable to use a vacuum laminator having a structure capable of thermocompression bonding the photosensitive layer in a vacuum chamber. Furthermore, if the photosensitive layer is heated as described above, it is not necessary to pre-heat the substrate in advance, but it is also possible to perform a pre-heat treatment on the substrate in order to further improve the followability.

Further, the flexible printed board sheet on which the photosensitive layer is laminated is passed through a process in which the roll-shaped flexible printed board sheet is continuously fed out and the photosensitive layer is continuously laminated by heating and pressing the flexible printed board sheet. The sheet can be wound into a roll.
In the step of continuously laminating the photosensitive layers, in order to further improve the followability of the photosensitive layer to the flexible printed board, it is preferable to perform heat compression under a reduced pressure of 4 × 10 ³ Pa or less using a vacuum laminator.

The thus-laminated photosensitive layer is then imagewise exposed to active light using a negative or positive film. At this time, if the polymer film present on the photosensitive layer is transparent, it may be exposed as it is,
If it is opaque, it must be removed. From the viewpoint of protection of the photosensitive layer, the polymer film is transparent, and it is preferable to expose the polymer film while leaving the polymer film remaining. Active light is a known active light source, for example,
Light generated from a carbon arc, a mercury vapor arc, a xenon arc, and others is used. As the light source, a flood light bulb for photography, a sun lamp, or the like is used in addition to the above.

The layer of the photosensitive resin composition imagewise exposed to active light can be heated after exposure to induce or promote bridging of the exposed portion. Heating after exposure is
For example, heating is performed at a temperature of 85 to 110 ° C. for 5 to 60 minutes.

After exposure, if a polymer film is present on the photosensitive layer, the polymer film is removed and then removed using a known developer such as an aqueous alkali solution or an aqueous surfactant solution, for example, by spraying or shaking. Unexposed portions are removed and developed by a known method such as dynamic immersion, brushing, and scraping.
Examples of the base of the aqueous alkali solution include alkali hydroxides such as lithium, sodium or potassium hydroxide, alkali carbonates such as lithium, sodium or potassium carbonate or bicarbonate, and alkali metals such as potassium phosphate and sodium phosphate. Phosphates, sodium pyrophosphate,
An alkali metal pyrophosphate such as potassium pyrophosphate is used, and an aqueous solution of sodium carbonate is particularly preferable.
The pH of the aqueous alkali solution used for development is preferably 9-1.
1, and the temperature is adjusted according to the developability of the photosensitive layer. A surfactant, an antifoaming agent, an organic solvent, and the like may be added to the aqueous alkali solution.

The surfactant in the aqueous surfactant solution is not particularly limited, and any of an anionic surfactant, a cationic surfactant, and a nonionic surfactant (nonionic surfactant) can be used. Examples of the anionic surfactant include sodium lauryl alcohol sulfate, sodium oleyl alcohol sulfate, sodium lauryl sulfate, ammonium lauryl sulfate, and sodium dodecylbenzenesulfonate. Examples of the cationic surfactant include stearylamine hydrochloride. Salts, lauryltrimethylammonium chloride, alkylbenzenedimethylammonium chloride, and the like. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene aryl ether, polyoxyethylene alkyl aryl ether, and polyoxyethylene derivative. , Oxyethylene / oxypropylene block copolymer, sorbitan fatty acid ester, glycerin fatty acid ester,
Examples thereof include polyoxyethylene fatty acid esters and polyoxyethylene alkylamines, and particularly preferred are nonionic surfactants such as polyoxyethylene aryl ether, polyoxyethylene alkyl aryl ether, and polyoxyethylene derivatives.

The concentration of the surfactant is 0.01 to 15% by weight.
, Preferably 0.1 to 10% by weight, particularly preferably 0.5 to 5% by weight.

Further, after development, the coverlay for the flexible printed board may be irradiated with active light from a high-pressure mercury lamp or the like for the purpose of improving solder heat resistance, chemical resistance and the like. The irradiation amount of this active light is 0.2 to 10 J /
cm ² , and heating at 60 to 180 ° C. may be performed during irradiation. After development, heating may be performed for the same purpose. Heating should be 15 ~
It is preferably performed for 90 minutes. Both the step of irradiating the active light and the step of heating may be performed. In that case, both steps can be performed in any order.

[0087]

Next, the present invention will be described by way of examples. Synthesis Example 1 [Synthesis of dicarboxylic acid having oxyalkylene group] In a flask equipped with a stirrer, a thermometer, a cooling tube, a distilling tube, and a nitrogen gas introducing tube, polyoxypropylene diamine (trade name, manufactured by Huntsman Corporation, trade name: Jeffamine) D
2,000 parts by weight, average molecular weight 2000), 2,000 parts by weight, and 384 parts by weight of trimellitic anhydride were added, and the condensed water produced as a by-product was azeotropically distilled off with toluene in the course of 1 hour under nitrogen gas aeration. The temperature was raised to 200 ° C. After keeping the temperature at the same temperature for 2 hours to complete the dehydration imidization reaction, the mixture was cooled to obtain a polyoxyalkylenediamine derivative (polyoxyalkylenediimide dicarboxylic acid).

Synthesis Example 2 [Synthesis of dicarboxylic acid having oxyalkylene group] A poly (oxyethylene oxypropylene) diamine (A) was placed in a flask equipped with a stirrer, a thermometer, a cooling tube, a distilling tube, and a nitrogen gas introducing tube. Huntsman Corporation product name, Jeffamine ED-2001, average molecular weight 200
0) 2000 parts by weight and 384 parts by weight of trimellitic anhydride were charged, and the mixture was heated to 200 ° C. over 1 hour while azeotropically distilling off by-product condensed water with toluene under nitrogen gas aeration. The temperature rose. After keeping the temperature at the same temperature for 2 hours to complete the dehydration imidization reaction, the mixture was cooled to obtain a polyoxyalkylenediimide dicarboxylic acid.

Synthesis Example 3 [Synthesis of Dicarboxylic Acid Having Oxyalkylene Group] A flask equipped with a stirrer, a thermometer, a cooling tube, a distilling tube, and a nitrogen gas introducing tube was charged with α, ω- (3-aminopropyl). −
Polyethylene glycol (trade name, manufactured by Koei Chemical Industry Co., Ltd.
PEGPA-1000, average molecular weight 1100) 1922
Parts by weight and 76 parts by weight of trimellitic anhydride were added, and the temperature was raised to 200 ° C. over 1 hour while azeotropically distilling off by-produced condensed water with toluene under nitrogen gas aeration. After keeping the temperature at the same temperature for 3 hours to complete the dehydration imidization reaction, the mixture was cooled to obtain a polyoxyalkylenediimide dicarboxylic acid.

Synthesis Example 4 [Synthesis of Component (A)] In a flask equipped with a stirrer, a thermometer, a cooling pipe and a nitrogen gas inlet pipe, 643 parts by weight of the polyoxyalkylenediimide dicarboxylic acid obtained in Synthesis Example 1 was added.
Adipic acid 49 parts by weight, sebacic acid 68 parts by weight, isophthalic acid 55 parts by weight, terephthalic acid 55 parts by weight, dimer acid 2 parts by weight, 4,4'-diphenylmethane diisocyanate 63 parts by weight, tolylene diisocyanate (2,4-
176 parts by weight of isomer / 2,6-isomer = 80/20 mol%) and 1200 parts by weight of γ-butyrolactone were charged,
The temperature was raised to 200 ° C. over 1.5 hours while venting the by-produced carbon dioxide gas out of the system under nitrogen gas ventilation.
After keeping the temperature at the same temperature for 3 hours to complete the decarboxylation amidation reaction, the solution was cooled to 130 ° C. to obtain a solution of the amide oligomer.

Next, 298 parts by weight of Epomic R140P (trade name of bisphenol A type epoxy resin, manufactured by Mitsui Petrochemical Industry Co., Ltd.) and N, N-dimethylformamide 4 were added to the solution of the amide oligomer kept at 130 ° C.
Then, the mixture was kept at the same temperature for 1.5 hours to complete the hydroxyethyl esterification reaction.
Then, a solution of a resin having a hydroxyl group was obtained.

Next, nitrogen gas ventilation was switched to dry air ventilation, and 58 parts by weight of methacrylic acid, 6 parts by weight of methquinone and 20 parts by weight of N, N-dimethylbenzylamine The mixture was added in parts by weight and kept at the same temperature for 1.5 hours to complete the epoxy group-capping reaction. Subsequently, while keeping the temperature at 115 ° C., 217 parts by weight of tetrahydrophthalic anhydride was added, and the mixture was kept at the same temperature for 2 hours to complete the half-esterification reaction.
After cooling to 70 ° C and keeping the temperature at 70 ° C, 25 parts by weight of 2-isocyanateethyl methacrylate was further added. Thus, a hydrophilic polyamide resin (A-1) having an acid value of 50 KOHmg / g in solid content was obtained.

Synthesis Example 5 Synthesis of Component (A) In Synthesis Example 4, the dicarboxylic acid having an oxyalkylene group obtained in Synthesis Example 1 was synthesized.
298 parts by weight of Epomic R140P and 217 parts by weight of tetrahydrophthalic anhydride are substituted for the dicarboxylic acid having an oxyalkylene group obtained in the above.
A hydrophilic polyamide-based resin (A-2) having an acid value of 36 KOHmg / g of solid content was obtained in the same manner as in Synthesis Example 4 except that 25 parts by weight of 2-isocyanateethyl methacrylate was replaced by 15 parts by weight to 0 parts by weight. Was.

Synthesis Example 6 [Synthesis of Component (A)] In a flask equipped with a stirrer, a thermometer, a cooling pipe and a nitrogen gas inlet pipe, 296 weight parts of the hydrophilic dicarboxylic acid having an oxyalkylene group obtained in Synthesis Example 3 was added. Parts, adipic acid 14 parts by weight, sebacic acid 19 parts by weight, isophthalic acid 15 parts by weight, terephthalic acid 15 parts by weight, dimer acid 1.1 parts by weight, 4,4'-diphenylmethane diisocyanate 20 parts by weight, tolylene diisocyanate (2 , 4-isomer / 2,6-isomer = 80/20 mol%) and 55 parts by weight of γ-butyrolactone were charged, and carbon dioxide gas produced as a by-product was removed from the system under nitrogen gas aeration. The temperature was raised to 200 ° C. over 1.5 hours while evacuating. After keeping the temperature at the same temperature for 3 hours to complete the decarboxylation amidation reaction, the solution was cooled to 130 ° C. to obtain a solution of the amide oligomer.

Next, 2 parts by weight of Epomic R301 (trade name, manufactured by Mitsui Petrochemical Industries, Ltd., bisphenol A type epoxy resin) and Epototo YDF-2001 (Toto Kasei) were added to a solution of the polyamide intermediate kept at 130 ° C.
(Product name, bisphenol F type epoxy resin) 28
0 parts by weight and 773 parts by weight of N, N-dimethylformamide were added, and the mixture was kept at the same temperature for 2.5 hours to complete the hydroxyethyl esterification reaction, and then cooled to 115 ° C. to obtain a resin having a hydroxyl group. A solution was obtained.

Next, nitrogen gas ventilation was switched to dry air ventilation, and 13 parts by weight of methacryl, 0.09 parts by weight of methquinone and N, N-dimethylbenzylamine were added to a solution of a resin having a hydroxyl group kept at 115 ° C. 9
The weight part was added, and the temperature was kept at the same temperature for 3 hours to complete the epoxy group sealing reaction. Subsequently, 183 parts by weight of tetrahydrophthalic anhydride was added while maintaining the temperature at 115 ° C., and the temperature was maintained at the same temperature for 1 hour to complete the half-esterification reaction. A-
3) was obtained.

Example 1 Each of the materials shown in Tables 1 and 2 was blended to prepare a solution of the photosensitive resin composition.

[0098]

[Table 1]

[0099]

[Table 2]

The solution of the photosensitive resin composition obtained was
m on a polyethylene terephthalate film having a thickness of 10 m and a hot air convection dryer at 80 to 110 ° C.
Drying for a minute removed the solvent. The dried thickness of the photosensitive resin composition layer was 50 μm. On the photosensitive resin composition layer, a polyethylene film having a thickness of 25 μm was further adhered as a protective film to obtain a photosensitive element of the present invention. Circuit embedding and photosensitive properties of the obtained photosensitive element, solder heat resistance after forming the resist, cleaning agent resistance, folding resistance, flame retardancy, storage stability and electrolytic corrosion resistance are evaluated by the following methods, The results are shown in Table 4.

(1) Circuit embedding property A flexible lithographic printed circuit board (trade name: F, manufactured by Nickan Industry Co., Ltd.) in which a 35 μm thick copper foil is laminated on a polyimide substrate
30VC125RC11) copper foil was etched according to a conventional method, and line / space (μm) = 165/165,
A continuous vacuum laminator (trade name: VLM-, manufactured by Hitachi Chemical Co., Ltd.) is formed on a flexible printed board on which three test pattern copper circuits 318/318 and 636/636 are formed.
Laminating the photosensitive element with a heat shoe temperature of 120 ° C., a laminating speed of 0.5 m / s, an air pressure of 4000 Pa or less, and a pressure of 3.0 × 10 ⁵ Pa, while peeling off the polyethylene film. did.

Subsequently, the three test pattern portions were visually observed with a stereoscopic microscope to check for the presence of bubbles or the like around the copper circuit. The three test pattern portions were cut out, and the copper circuit cross section was observed by epoxy casting. A sample was prepared, and the follow-up situation of the coverlay around the copper circuit was checked with an electron microscope to determine the circuit embedding property. The evaluation criteria are as follows. Good: No air bubbles remained, no gap around copper circuit. Bad: Air bubbles remained, or air gap around copper circuit.

(2) Photosensitive properties (alkali developability, sensitivity,
(Resolution) Flexible printed circuit board (product name: F, manufactured by Nikkan Kogyo Co., Ltd.)
The copper surface of 30VC125RC11) was polished with an abrasive brush, washed with water and dried. A continuous vacuum laminator (manufactured by Hitachi Chemical Co., Ltd.)
Using the product name VLM-1), the heat shoe temperature is 1
20 ° C, lamination speed 0.5m / s, air pressure 4000P
a Hereinafter, the photosensitive element was laminated at a pressure of 3.0 × 10 ⁵ Pa while peeling off the polyethylene film.

Next, Kodak Step Tablet No. 2 (manufactured by Eastman Kodak Co., Ltd., 21-step step tablet) was brought into close contact with the polyethylene terephthalate film of the obtained sample, and HMW manufactured by Oak Manufacturing Co., Ltd. was used.
Exposure was carried out in a predetermined amount using a -201GX type exposure machine. Further, a 1% by weight aqueous solution of sodium carbonate was spray-developed at 30 ° C. for 120 seconds as an alkali developing solution. Sensitivity.

Also, a photo tool (Kodak Step Tablet No. 2 and line / space (μm) = 30/3)
A photo tool having a negative pattern of 0 to 250/250 (resolution) and line / space (μm) = 30/400 to 250/400 (adhesion)) is adhered onto the polyethylene terephthalate film of the obtained sample. Then, exposure was carried out at an exposure amount capable of obtaining eight step tablets, and the value of the smallest resolution at which a rectangular resist shape was obtained when developed and the value of the line / space of the adhesive pattern were taken as the resolution.

(3) Solder heat resistance In the same manner as in the above (2), a test negative mask was brought into close contact with the sample of polyethylene terephthalate film obtained by laminating the photosensitive element on the flexible printed board substrate, and the number of step tablets was 8 steps. Exposure was performed at the obtained exposure amount. After leaving at room temperature for 1 hour, the polyethylene terephthalate film of the sample was peeled off, spray-developed at 30 ° C. for 120 seconds using a 1% by weight aqueous sodium carbonate solution as an alkaline developer, and dried at 80 ° C. for 10 minutes. Then, using a Toshiba UV irradiator manufactured by Toshiba Electric Materials Co., Ltd., UV irradiation at ³ J / cm ² was performed, and further, heat treatment was performed at 150 ° C. for 45 minutes to obtain a flexible printed board on which a coverlay was formed.

Next, a rosin flux MH-820 was used.
After applying V (manufactured by Tamura Kaken Co., Ltd.), it was immersed in a solder bath at 260 ° C. for 30 seconds to perform a soldering treatment. After such an operation, the occurrence of cracks in the coverlay, and the situation of lifting and peeling of the coverlay from the substrate were visually evaluated according to the following criteria. Good: No cracks, floating and peeling. Bad: Cracks, floating and peeling.

(4) Cleaning Agent Resistance A flexible printed board on which a coverlay was formed by the same operation as in (3) above was used as a substitute for Freon AK225 manufactured by Asahi Glass Co., Ltd.
After immersing in AES and boiling for 5 minutes, washing with water for 3 minutes,
The state of lifting and peeling of the coverlay from the substrate was visually evaluated according to the following criteria. Good: No floating or peeling. Bad: Floating or peeling.

(5) Folding resistance A coverlay was formed on the substrate for a flexible printed board obtained by the same operation as in the above (3), and the sample subjected to the soldering treatment was bent 180 ° by bending and bending. The state of occurrence of cracks in the coverlay was visually evaluated according to the following criteria. Good: No cracks occurred Bad: Cracks occurred

(6) Flame-retardant substrate for flexible printed board (manufactured by Nickan Industry Co., Ltd.)
The heat shoe temperature was 120 ° C. and the laminate was laminated on a polyimide substrate with an adhesive obtained by removing the copper foil of trade name F30VC125RC11) by etching using a vacuum laminator (trade name: VLM-1 type, manufactured by Hitachi Chemical Co., Ltd.). The speed is 0.5m / s, the air pressure is 4000Pa or less, and the pressure is 3.0.
The photosensitive element was laminated at a pressure of × 10 ⁵ Pa while peeling off the polyethylene film.
Exposure was performed to obtain a step. After standing at room temperature for 1 hour, the polyethylene terephthalate film of the sample was peeled off, and spray-developed at 30 ° C. for 120 seconds using a 1% by weight aqueous solution of sodium carbonate as an alkali developing solution.
Dry at 0 ° C. for 10 minutes. Then, using Toshiba Denki Co., Ltd. UV irradiation device, UV irradiation of 3J / cm ² was performed,
Further, a heat treatment was performed at 150 ° C. for 45 minutes to obtain a flexible printed board on which a coverlay was formed. The flexible printed circuit board on which the obtained coverlay was formed was evaluated for flame retardancy according to UL94 standard.

(7) Storage stability A 90 m long photosensitive element wound in a roll is stored at a temperature of 23 ° C. and a humidity of 60%. Was visually evaluated according to the following criteria. Good: No exudation of the photosensitive layer even after 6 months Bad: Excess of the exudation of the photosensitive layer within 6 months

(8) Electric Corrosion Resistance A flexible printed board substrate (a product name: F3, manufactured by Nickan Industry Co., Ltd.) in which a 35 μm thick copper foil was laminated on a polyimide substrate.
0VC125RC11) was etched according to a conventional method, and the line / space (μm) = 165 / 165,3
18/318, 636/636 three test pattern IPC multi-purpose test pattern (IPC-
A substrate for a flexible printed board on which B-25) was formed was produced. The copper surface of the flexible printed board is polished with an abrasive brush, washed with water and dried, and a continuous vacuum laminator (trade name VLM-1 manufactured by Hitachi Chemical Co., Ltd.) is placed on the flexible printed board. ), The heat shoe temperature is 120 ° C., the laminating speed is 0.5 m / s,
The photosensitive elements were laminated at a pressure of 4000 Pa or less and a pressure of 3.0 × 10 ⁵ Pa while peeling off the polyethylene film.

A test negative mask was adhered onto a polyethylene terephthalate film of a photosensitive element laminated on a substrate for a flexible printed board, and the exposure was performed with an exposure amount capable of obtaining eight steps of step tablets. After leaving at room temperature for 1 hour, the polyethylene terephthalate film of the sample was peeled off, spray-developed at 30 ° C. for 120 seconds using a 1% by weight aqueous sodium carbonate solution as an alkaline developer, and dried at 80 ° C. for 10 minutes. Next, Toshiba Electric Materials
Ultraviolet irradiation of 3 J / cm ² was performed using an ultraviolet irradiation apparatus manufactured by Toshiba Corporation, and a heat treatment was performed at 150 ° C. for 45 minutes to obtain a flexible printed board on which a coverlay was formed.

A conductor is soldered to the flexible printed board on which the coverlay has been formed, and the conductor is subjected to 85 ° C. and 85% RH.
Under the condition of 100 V was applied. After a lapse of 500 hours, the sample was taken out, and the appearance of the substrate and dendrite were observed visually and with a microscope of about 100 times, respectively.

Examples 2 to 5 and Comparative Examples 1 and 2 A photosensitive element was prepared in the same manner as in Example 1 except that the materials and the amounts shown in Table 3 were used. The results were shown in Table 4.

[0116]

[Table 3]

The respective materials in Table 3 are shown below. BPE500: 2,2-bis (4-methacryloxypentaethoxy) phenylpropane TM-A: urethane acrylate compound I- synthesized from 2 mol of trimethylhexamethylene diisocyanate, 2 mol of 2-hydroxyethyl methacrylate and 1 mol of cyclohexanedimethanol 369: 2-benzyl-2-dimethylamino-1-
(4-morpholinophenyl) -butanone-1 EAB: 4,4'-bis (diethylamino) benzophenone

Embedded image BL3175: a compound of the formula (I) in which R ¹ , R ² and R ³ are all hexylene groups and R ⁴ , R ⁵ and R ⁶ are groups obtained by removing a hydrogen atom from a hydroxyl group of methyl ethyl oxime; The compound (blocking agent) having the compound is methyl ethyl oxime PVP K120: polyvinylpyrrolidone K120
SPmel) Cymel 300: Melamine compound (Mitsui Toatsu Cymel)

[0118]

[Table 4]

As is clear from Table 4, by using the photosensitive resin composition and the photosensitive element of the present invention, alkali development can be performed, and solder heat resistance, washing liquid resistance, folding resistance, and storage stability can be attained. It can be seen that a coverlay for a flexible printed board having good electric corrosion resistance and flame retardancy of V-0 (UL94 standard) can be obtained.

[0120]

The photosensitive resin compositions according to claims 1 and 2 are alkali-developable, have excellent sensitivity and photocurability, can form patterns efficiently by photolithography, and have a cured product having folding resistance. It has excellent solder heat resistance, cleaning agent resistance, adhesion and flame retardancy, excellent workability of application on a film, and excellent corrosion resistance. The photosensitive resin composition according to the third aspect has the effects of the photosensitive resin composition according to the first or second aspect, and is more excellent in folding resistance and solder heat resistance. The photosensitive element according to claim 4 is excellent in sensitivity and photocurability, can form a pattern efficiently by photolithography, and has folding resistance, solder heat resistance, cleaning agent resistance, adhesion, flame retardancy and the like. Excellent resistance to electrolytic corrosion, excellent handling, and excellent workability of lamination on a substrate.

The photosensitive laminate according to claim 5 is excellent in sensitivity and photocurability, can form a pattern efficiently by photolithography, and has folding resistance, solder heat resistance, cleaning agent resistance, and flame retardancy. Also, it is excellent in electric corrosion resistance, excellent in handleability, and excellent in workability of manufacturing a flexible printed board.
The photosensitive laminate according to claim 6 is extremely excellent in sensitivity and photocurability, can form a pattern efficiently by photolithography, and has folding resistance, solder heat resistance, cleaning agent resistance, adhesion, and flame retardancy. Excellent in heat resistance and electrolytic corrosion resistance, extremely excellent in handleability, and excellent in workability in manufacturing a flexible printed board.

The method for producing a flexible printed board according to claim 7 is excellent in bending resistance, solder heat resistance, cleaning agent resistance, flame retardancy and electric corrosion resistance, and has high density packaging and electrical reliability. Excellent flexible printed boards can be manufactured with good workability and yield. The method for manufacturing a flexible printed board according to the eighth aspect has the effect of the method for manufacturing a flexible printed board according to the seventh aspect, and is more excellent in solder heat resistance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/027 H05K 3/28 D H05K 3/28 H01L 21/30 502R (72) Inventor Tatsuko Obata Ibaraki 4-13-1, Higashicho, Hitachi City Hitachi Chemical Co., Ltd., Ibaraki Research Laboratory (72) Inventor Jin Amanokura 4-3-1, Higashimachi, Hitachi City, Ibaraki Prefecture Hitachi Chemical Co., Ltd., Ibaraki Research Laboratory (72) Invention Person Tomohiko Akahori 4-13-1, Higashicho, Hitachi City, Ibaraki Prefecture Within Ibaraki Research Laboratory, Hitachi Chemical Co., Ltd. (72) Inventor Kenji Suzuki 4-3-1-1, Higashicho, Hitachi City, Ibaraki Prefecture, Hitachi Chemical Co., Ltd. F-term (reference) 2H025 AA01 AA10 AA13 AA14 AB11 AB15 AC01 AD01 BC42 CA01 CA27 CA28 CB24 CB43 CC20 EA04 EA08 FA03 FA17 FA29 FA30 2H096 AA26 BA05 BA20 CA12 CA16 CA20 EA02 GA08 HA01 HA03 JA04 5E314 AA27 AA36 BB13 CC01 FF06 GG10 GG11 GG14 GG26

Claims (8)

[Claims] 1. A resin having an amide bond, an oxyalkylene group and a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated group, and (C) a photopolymerization initiator. ) (Wherein, R ¹ , R ² and R ³ each independently represent a group having 1 to 1 carbon atoms)
2 represents an alkylene group or an arylene group having 6 to 14 carbon atoms, and R ⁴ , R ⁵ and R ⁶ each independently represent a residue obtained when a compound having an active hydrogen is reacted with an isocyanate). A photosensitive resin composition comprising the blocked isocyanate as an essential component. 2. Component (A) is (a) a dicarboxylic acid having an oxyalkylene group, (b) a diisocyanate or diamine, (c) a compound having two or more epoxy groups in one molecule, and The photosensitive resin composition according to claim 1, which is a resin obtained by reacting a monovalent carboxylic acid monoanhydride as an essential reaction component. 3. (A) 20 to 95 parts by weight of a resin, (B)
5 to 80 parts by weight of the photopolymerizable compound (provided that the total amount of the components (A) and (B) is 100 parts by weight), and 0.01 to 20 parts by weight of the photopolymerization initiator (C). The mixing ratio of (D) 1 to 50 parts by weight of the blocked isocyanate (based on 100 parts by weight of the total of the components (A) and (B)) with respect to 100 parts by weight of the total of the components and the component (B). The photosensitive resin composition according to claim 1, wherein 4. A photosensitive element comprising a layer of the photosensitive resin composition according to claim 1, 2 or 3, and a support film supporting the layer. 5. A photosensitive laminate having a layer of the photosensitive resin composition according to claim 1, 2 or 3 on a surface of a substrate for a flexible printed board. 6. A photosensitive laminate having a substrate for a flexible printed board on one surface of a layer of the photosensitive resin composition according to claim 1, 2 or 3, and a support film on the other surface. 7. A pattern of a photosensitive resin composition is formed on a surface of a substrate for a flexible printed board by irradiating the photosensitive laminate according to claim 5 imagewise with active light and developing it. Manufacturing method of flexible printed board. 8. The method for producing a flexible printed board according to claim 7, which comprises a step of irradiating with active light after the development and a step of post-heating.