TWI771439B - Laminated structure, dry film and flexible printed wiring board - Google Patents

Abstract

An object of the present invention is to provide a laminate structure, a dry film, and a cured product having flexibility as a protective film, which has high flexibility, particularly excellent crack resistance against excessive folding. printed wiring board. The solution is a laminated structure comprising a resin layer (A) and a resin layer (B) laminated on a flexible printed wiring board via the resin layer (A). The resin layer (B) is composed of a photosensitive thermosetting resin composition containing an alkali-soluble resin, a photopolymerization initiator, a thermally reactive compound, and a block copolymer, and the resin layer (A) is composed of a It consists of an alkali-developing resin composition of an alkali-soluble resin and a heat-reactive compound.

Description

Laminated structure, dry film and flexible printed wiring board

The present invention relates to a laminate structure, a dry film, and a flexible printed wiring board (hereinafter, also simply referred to as a "wiring board") useful as an insulating film for a flexible printed wiring board.

In recent years, due to the miniaturization and thinning of electronic apparatuses promoted by the popularization of smart phones and tablet terminals, it becomes necessary to reduce the space of circuit boards. Therefore, the use of flexible printed wiring boards that can be bent and accommodated is gradually expanding, and flexible printed wiring boards are required to have higher reliability than ever.

On the other hand, polyimide, which has excellent mechanical properties such as heat resistance and flexibility, is widely used at the bent portion (bending portion) as an insulating film for securing the insulating reliability of the flexible printed wiring board. A mixed-loading process using a photosensitive resin composition capable of microfabrication, which is excellent in electrical insulation and flux heat resistance, as a coating layer for the base (for example, refer to Patent Documents 1 and 2) in the mounting part (non-bending part) .

That is, the coating layer based on polyimide is not suitable for fine wiring because it must be processed by stamping from a die. Therefore, it is necessary to partially use an alkali-imageable photosensitive resin composition (solder resist) that can achieve processing by photolithography in the chip mounting portion that requires fine wiring. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 62-263692 [Patent Document 2] Japanese Patent Laid-Open No. 63-110224

[The problem to be solved by the invention]

Therefore, in the manufacturing process of the conventional flexible printed wiring board, a mixed process of attaching a cladding layer and forming a solder resist has to be used, so there are problems of poor cost and workability.

On the other hand, the application of the insulating film as a solder resist or the insulating film as a cladding layer as a solder resist and a cladding layer of a flexible printed wiring board has been reviewed so far. Materials that can fully meet the performance requirements of both the solder resist and the cladding layer have not yet been put into practical use.

Specifically, in order to reduce the space required for circuit boards, when a flexible printed wiring board is housed in a machine, the flexible printed wiring board on which the components are mounted is folded and stored by bending it. . Therefore, the flexible printed wiring board and its insulating film become loaded in the folded state, but on this side, the actual situation is still not enough to meet the requirements of both the solder resist and the coating layer. performance material. Here, folding means bending the upper surface of the flexible printed wiring board by 180°. Therefore, flexible printed wiring boards are required to have higher flexibility than hitherto, especially insulating films suitable for solder resists and coating layers that have excellent crack resistance even if they are folded excessively.

Therefore, the main object of the present invention is to provide a laminated structure which satisfies the required properties of both the solder resist and the coating layer, and has the high flexibility as hitherto, in particular, excellent crack resistance even if it is over-folded. Another object of the present invention is to provide an insulating film for a flexible printed wiring board, especially a laminate structure suitable for a process of integrally forming a bent portion (curved portion) and a mounting portion (non-curved portion), a dry A film, and a flexible printed wiring board having a cured product thereof as a protective film, for example, a cladding layer or a solder resist. [means to solve the problem]

The inventors of the present invention have completed the present invention as a result of earnest studies in order to solve the above-mentioned problems. That is, the laminated structure of the present invention is characterized by having: a resin layer (A), and a resin layer (B) laminated on a flexible printed wiring board via the resin layer (A); the aforementioned resin The layer (B) is composed of a photosensitive thermosetting resin composition containing an alkali-soluble resin, a photopolymerization initiator, a thermally reactive compound, and a block copolymer, and the resin layer (A) is composed of a It consists of an alkali-soluble resin and an alkali-developing resin composition of a thermally reactive compound.

In the laminate structure of the present invention, the block copolymer preferably has a structure represented by the following formula (I), and the mass average molecular weight (Mw) of the block copolymer is preferably 20,000 to 400,000. X-Y-X (I) (In formula (I), X is a polymer unit whose glass transition temperature Tg is above 0°C, which may be the same or different, and Y is a polymer unit whose glass transition temperature Tg is less than 0°C .)

Moreover, in the laminated structure of this invention, it is preferable to already contain a photobase generator as a photopolymerization initiator of the said resin layer (B). Furthermore, in the laminate structure of the present invention, the resin layer (A) is preferably composed of an alkali-developing resin composition that does not contain a photopolymerization initiator.

The laminated structure of the present invention can be used for at least any one of the curved portion and the non-curved portion of a flexible printed wiring board, and can also be used for a coating layer and a solder resist of a flexible printed wiring board. and at least any one of the interlayer insulating materials.

Furthermore, the dry film of the present invention is characterized by being supported or protected by the film on at least one side of the laminate structure of the present invention.

Further, the flexible printed wiring board of the present invention is characterized by having an insulating film using the laminate structure of the present invention.

Here, the flexible printed wiring board of the present invention may have a layer in which the above-mentioned laminated structure of the present invention is formed on the flexible printed wiring board, patterned by light irradiation, and once in a developing solution An insulating film formed by a pattern. Moreover, instead of using the laminate structure of the present invention, the resin layer (A) and the resin layer (B) may be sequentially formed on the flexible printed wiring board, and then patterned by light irradiation, An insulating film formed by forming a pattern in a developing solution at one time. Furthermore, in the present invention, "pattern" refers to a pattern-shaped cured product, that is, an insulating film. [Effect of invention]

According to the present invention, it is possible to provide a laminate structure which satisfies the required performance of both the solder resist and the coating layer, and has high flexibility as compared to the past, and in particular, has excellent crack resistance even if it is folded excessively. In addition, it becomes possible to realize an insulating film suitable for a flexible printed wiring board, especially a laminate structure, a dry film, and a one-shot forming process of a bent portion (curved portion) and a mounting portion (non-curved portion), and , with its hardened product as a protective film, for example, a flexible printed wiring board of a cladding layer or a solder resist.

Hereinafter, embodiments of the present invention will be described in detail. (Laminated Structure) The laminated structure of the present invention has a resin layer (A) and a resin layer (B) laminated on a flexible printed wiring board via the resin layer (A). Here, in the laminate structure of the present invention, the resin layer (A) and the resin layer (B) substantially function as an adhesive layer and a protective layer, respectively. The laminated structure of the present invention has a resin layer (B) composed of a photosensitivity comprising an alkali-soluble resin, a photopolymerization initiator, a thermally reactive compound and a block copolymer (also referred to as "BCP"). It consists of a thermosetting resin composition, and at the same time, the resin layer (A) is a characteristic point which consists of an alkali-developing resin composition consisting of an alkali-soluble resin and a heat-reactive compound.

In the present invention, in the laminated structure formed by laminating two resin layers, the resin layer (B) on the upper layer side contains the block copolymer, so that the high bending can be achieved in a well-balanced manner. properties, especially excellent crack resistance to over-folding, and excellent heat resistance.

Furthermore, the laminate structure of the present invention can be a flexible printed wiring board in which a copper circuit has been formed on a flexible substrate, and has a resin layer (A) and a resin layer (B) in this order, and the upper layer side The resin layer (B) is composed of a photosensitive thermosetting resin composition that can be patterned by light irradiation, and even if the resin layer (A) on the lower side does not contain a photopolymerization initiator, the resin layer ( B) and the resin layer (A) can also be patterned at one time by developing.

The reason for this is that the resin layer (A) on the printed wiring board side does not contain a photopolymerization initiator. Generally speaking, the resin layer (A) cannot be patterned as a single layer, but in the present invention In the laminated structure, the active species such as radicals generated from the photopolymerization initiator contained in the resin layer (B) above it diffuses to the resin layer (A) immediately below during exposure, Therefore, it becomes possible to pattern both layers at the same time.

[Resin layer (A)] (Alkali-developing resin composition) The alkali-developing resin composition constituting the resin layer (A) may contain one or more functional groups among phenolic hydroxyl groups and carboxyl groups and can The composition of an alkali-soluble resin developed with an alkali solution and a heat-reactive compound is sufficient. Preferably, for example, a resin composition containing a compound having a phenolic hydroxyl group, a compound having a carboxyl group, and a compound having a phenolic hydroxyl group and a carboxyl group can be used, and a well-known and conventional one can be used.

For example, a resin composition containing a carboxyl group-containing resin or a carboxyl group-containing photosensitive resin, a compound having an ethylenically unsaturated bond, and a thermally reactive compound, which has been conventionally used as a solder resist composition, can be mentioned.

Here, as the carboxyl group-containing resin or the carboxyl group-containing photosensitive resin, and the compound having an ethylenically unsaturated bond, a known and conventional compound can be used. In addition, as the thermally reactive compound, the same as the thermally reactive compound used in the resin layer (B), a known and conventional compound having a functional group such as a cyclic (thio)ether group that can be hardened and reacted by heat can be used.

Such a resin layer (A) may or may not contain a photopolymerization initiator, and examples of the photopolymerization initiator used when the photopolymerization initiator is included include those used in the resin layer (B). The photopolymerization initiator is the same.

Furthermore, in the present invention, the resin layer (B) must contain a block copolymer, but the resin layer (A) may be made to the extent that the effect of the present invention, that is, the required performance of both the solder resist and the coating layer, is not affected. ) contains block copolymers. As the block copolymer in this case, the same block copolymer as that used for the resin layer (B) can be used. The compounding amount of the block copolymer in the resin layer (A) is preferably 15 parts by mass or less, preferably 3 parts by mass or less, particularly preferably the resin layer (A), relative to 100 parts by mass of the alkali-soluble resin. ) does not contain the block copolymer, but only the resin layer (B) contains the block copolymer. If the compounding quantity of a block copolymer is 15 mass parts or less, it will not affect the developing property, bendability, crack resistance, and heat resistance.

[Resin layer (B)] (Photosensitive thermosetting resin composition) The photosensitive thermosetting resin composition constituting the resin layer (B) contains an alkali-soluble resin, a photopolymerization initiator, and a thermally reactive compound, and block copolymers.

(Alkali-Soluble Resin) As the alkali-soluble resin, known and conventional ones similar to those used for the above-mentioned resin layer (A) can be used, and those having an imide structure which are more excellent in properties such as bending resistance and heat resistance can be suitably used. Carboxyl group-containing resin of at least any one of amide structures. Examples of the carboxyl group-containing resin having at least one of an imide structure and an imide structure include (1) a carboxyl group-containing resin having an imide structure and an imide structure, and (2) a carboxyl group-containing resin having an imide structure. However, carboxyl-containing resins that do not have an amide structure, and (3) carboxyl-containing resins that have an amide structure but do not have an amide structure; these resins can be used alone or as a mixture of two or more. In the present invention, among the carboxyl group-containing resins having at least one of an imide structure and an imide structure, it is preferable to use a carboxyl group-containing resin having an imide structure and an imide structure. Furthermore, the carboxyl group-containing resin having at least one of an imide structure and an imide structure may further have a phenolic hydroxyl group.

(1) Carboxyl group-containing resin with imide structure and imide structure The carboxyl group-containing resin with imide structure and imide structure is preferably a polyimide resin. Diamine of amine, after reacting with acid anhydride (a1) containing at least 3 carboxyl groups and 2 anhydrous acid anhydrides among them to obtain imide compound, and making imide compound containing obtained imide compound and diisocyanate compound The reaction raw materials are obtained from the reaction. As will be described later, it is preferable that the above-mentioned reaction raw material contains, in addition to the above-mentioned imide compound and diisocyanate compound, an acid anhydride (a2) having at least three carboxyl groups and two of these anhydrides.

Here, the diamine used for the synthesis of the above-mentioned polyamide imide resin contains at least a carboxyl group-containing diamine, and a diamine having an ether bond is preferably used together. Examples of the carboxyl group-containing diamine include diaminobenzoic acids such as 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, and 3,4-diaminobenzoic acid, 3,5-diaminobenzoic acid, and the like. Aminophenoxybenzoic acids such as 5-bis(3-aminophenoxy)benzoic acid, 3,5-bis(4-aminophenoxy)benzoic acid, 3,3'-methylenebis (6-aminobenzoic acid), carboxybiphenyl compounds such as 3,3'-diamino-4,4'-dicarboxybiphenyl, 3,3'-diamino-4,4'-diphenyl Carboxydiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane and other carboxydiphenylalkanes, 3,3'-diamino-4,4'-diphenylmethane Carboxydiphenyl ether compounds such as carboxydiphenyl ether and the like can be used alone or in combination as appropriate.

In addition, as the diamine having an ether bond, for example, polyoxyethylene diamine or polyoxypropylene diamine can be mentioned, and other examples include polyoxyalkylene groups including oxyalkylene groups having different carbon chain numbers. Diamine etc. The molecular weight of the diamine with ether bond is preferably 200-3,000, preferably 400-2,000. Examples of polyoxyalkylene diamines include polyoxyethylene diamines such as Jeffamine ED-600, ED-900, ED-2003, EDR-148, and HK-511 manufactured by Huntsman, USA, or Jeffamine D -230, D-400, D-2000, D-4000, etc. polyoxypropylene diamine, or Jeffamine XTJ-542, XTJ533, XTJ536, etc. with polytetramethylene ethylene oxide, etc. Moreover, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane can also be used as a diamine which has an ether bond.

As such a diamine, diamines other than these may be used in combination. As other diamines that can be used in combination, general-purpose aliphatic diamines, aromatic diamines, or the like can be used alone or in suitable combination. Specifically, as other diamines, for example, p-phenylene diamine (PPD), 1,3-diaminobenzene, 2,4-toluenediamine, diamine having one benzene nucleus, Diaminodiphenyl ethers such as 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, etc., 4 ,4'-Diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl Benzene, 1,3-bis(3-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,3-bis[2-(4-aminophenyl)isopropyl] phenyl]benzene, 1,4-bis[2-(3-aminophenyl)isopropyl]benzene, 3,3'-bis(3-aminophenoxy)biphenyl, 3,3'-bis (4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, bis[ 3-(3-Aminophenoxy)phenyl]ether, bis[3-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl] Aromatic diamines such as ethers, 3,3'-diamino-4,4'-dihydroxydiphenyl ethylene, 1,2-diaminoethane, 1,3-diaminopropane, 1, Fatty acids such as 4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, etc. family of diamines.

The acid anhydride (a1) used in the synthesis of the above-mentioned polyamide imide resin includes an acid anhydride having at least 3 carboxyl groups and 2 of which are anhydrous. Examples of the acid anhydride include those having at least one of an aromatic ring and an aliphatic ring, and those having an aromatic ring include, for example, anhydrous trimellitic acid (trimellitic anhydride) (benzene- 1,2,4-Tricarboxylic acid 1,2-anhydrate, TMA), 4,4'-oxydiphthalic anhydride, etc. As those having an aliphatic ring, for example, hydrogenated trimellitic anhydride (cyclohexane Alkane-1,2,4-tricarboxylic acid-1,2-anhydrate, H-TMA), etc. These acid anhydrides may be used alone or in combination of two or more. In addition, carboxylic dianhydride may be used in combination. Examples of the carboxylic dianhydride include pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, and tetracarboxylic anhydride.

As the diisocyanate compound used in the synthesis of the above-mentioned polyimide resin, for example, aromatic diisocyanates and their isomers or polymers, aliphatic diisocyanates, alicyclic diisocyanates and their isocyanides can be used. Diisocyanates such as structures, or other commonly used diisocyanates, but are not limited to these. In addition, these diisocyanate compounds may be used alone or in combination.

As described above, the polyamide imide resin can be obtained by reacting the reaction raw materials containing an imide compound and a diisocyanate compound, and the acid anhydride used for obtaining an imide compound can also be contained as The same anhydride (a2). As this acid anhydride (a2), the same thing as said acid anhydride (a1) can be used, and a different thing can also be used. The content of the acid anhydride (a2) in the reaction raw material at this time is not particularly limited.

As described above, the polyamide imide resin described above, in the viewpoint of improving alkali solubility and developing property, is especially based on the use of carboxyl-containing diamine and diamine with ether bond, and alicyclic trimellitic acid. That is, H-TMA is preferable. In addition, for the same reason, it is also preferable to use an aliphatic diisocyanate compound in the second-stage reaction of such a polyamide imide resin. Thereby, by effectively introducing an aliphatic chain or an alicyclic structure into the structure, it becomes possible to improve the alkali solubility without significantly lowering the characteristics.

Further, as the carboxyl group-containing resin having an imide structure and an imide structure, a polyimide imide resin having a structure represented by the following general formula (1) and a structure represented by the following general formula (2) can be used. .

Here, X ₁ is the residue of an aliphatic diamine (a) derived from a dimer acid having 24 to 48 carbon atoms. X ₂ is the residue of the aromatic diamine (b) having a carboxyl group. Y is each independently a cyclohexane ring or an aromatic ring.

Specifically, as a polyimide imide resin having such a structure, one represented by the following general formula (3) can be mentioned.

In the above general formula (3), X is each independently a diamine residue, Y is each independently an aromatic ring or a cyclohexane ring, and Z is a residue of a diisocyanate compound. n is a natural number.

(2) Carboxyl group-containing resin having an imide structure but not having an imide structure Carboxyl group-containing resin having an imide structure but not having an imide structure is not particularly limited as long as it is a resin having a carboxyl group and an imide ring. For the synthesis of the carboxyl group-containing resin having an imide structure but not having an imide structure, a known conventional method of introducing an imide ring into the carboxyl group-containing resin can be used. For example, the resin obtained by making a carboxylic anhydride component, and an amine component and/or an isocyanate component react can be mentioned. The imidization may be thermal imidization, chemical imidization, or a combination of these may be used for production.

Here, as the carboxylic acid anhydride component, for example, tetracarboxylic anhydride, tricarboxylic acid anhydride, etc. can be mentioned, but it is not limited to these acid anhydrides, as long as it is a compound having an acid anhydride group and a carboxyl group that react with an amine group or an isocyanate group , and its derivatives can also be used. In addition, these carboxylic anhydride components may be used alone or in combination.

As the tetracarboxylic acid anhydride, for example, pyromellitic dianhydride, 3-fluoromellitic dianhydride, 3,6-difluoromellitic dianhydride, 3,6-bis(trifluoromethyl dianhydride) may be mentioned. ) pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 4,4 '-Oxydiphthalic acid dianhydride, 2,2'-difluoro-3,3',4,4'-biphenyltetracarboxylic dianhydride, 5,5'-difluoro-3,3',4 ,4'-biphenyltetracarboxylic dianhydride, 6,6'-difluoro-3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',5,5', 6,6'-hexafluoro-3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2'-bis(trifluoromethyl)-3,3',4,4'- Biphenyltetracarboxylic dianhydride, 5,5'-bis(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, 6,6'-bis(trifluoromethyl) Methyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',5,5'-tetra(trifluoromethyl)-3,3',4,4' - Biphenyltetracarboxylic dianhydride, 2,2',6,6'-tetra(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, 5,5 ',6,6'-4(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, and 2,2',5,5',6,6'- Lu(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3,3",4,4 "-Terphenyltetracarboxylic dianhydride, 3,3'",4,4'"-Tetraphenyltetracarboxylic dianhydride, 3,3"",4,4""-p-pentylphenyl Tetracarboxylic dianhydride, methylene-4,4'-diphthalic dianhydride, 1,1-ethynylene-4,4'-diphthalic dianhydride, 2,2-propylene-4, 4'-diphthalic dianhydride, 1,2-ethylidene-4,4'-diphthalic dianhydride, 1,3-trimethylene-4,4'-diphthalic dianhydride, 1,4 -Tetramethylene-4,4'-diphthalic acid dianhydride, 1,5-pentamethylene-4,4'-diphthalic acid dianhydride, 2,2-bis(3,4-dicarboxybenzene base)-1,1,1,3,3,3-hexafluoropropane dianhydride, difluoromethylene-4,4'-diphthalic acid dianhydride, 1,1,2,2-tetrafluoro-1 ,2-Ethylene-4,4'-diphthalic acid dianhydride, 1,1,2,2,3,3-hexafluoro-1,3-trimethylene-4,4'-diphthalic acid bis Anhydride, 1,1,2,2,3,3,4,4-Octafluoro-1,4-tetramethylene-4,4'-diphthalic acid dianhydride, 1,1,2,2,3 ,3,4,4,5,5-Decafluoro-1,5-pentamethylene-4,4'-diphthalic acid dianhydride, thio-4,4'-diphthalic acid dianhydride, sulfonic acid dianhydride Base-4,4'-diphthalic dianhydride, 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethylsiloxane dianhydride, 1,3- Bis(3,4-dicarboxyphenyl)phthalic anhydride, 1,4-bis(3,4-dicarboxyphenyl)phthalic anhydride, 1,3- Bis(3,4-dicarboxyphenoxy)phthalic anhydride, 1,4-bis(3,4-dicarboxyphenoxy)phthalic anhydride, 1,3-bis[2-(3,4-bis Carboxyphenyl)-2-propyl]phthalic anhydride, 1,4-bis[2-(3,4-dicarboxyphenyl)-2-propyl]phthalic anhydride, bis[3-(3,4 -Dicarboxyphenoxy)phenyl]methane dianhydride, bis[4-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, 2,2-bis[3-(3,4-bis[4-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride Carboxyphenoxy)phenyl]propanedianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propanedianhydride, 2,2-bis[3-(3,4 -Dicarboxyphenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl ] Propane dianhydride, bis(3,4-dicarboxyphenoxy)dimethylsilane dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)-1,1,3,3-tetra Methyldisiloxane dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 1,2,5,6-naphthalene tetracarboxylic dianhydride, 3,4,9,10-perylene tetracarboxylic acid Acid dianhydride, 2,3,6,7-anthracene tetracarboxylic dianhydride, 1,2,7,8-phenanthrene tetracarboxylic dianhydride, 1,2,3,4-butane tetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexane-1,2,3,4-tetracarboxylic dianhydride, cyclohexane-1, 2,4,5-tetracarboxylic dianhydride, 3,3',4,4'-biscyclohexyltetracarboxylic dianhydride, carbonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid ) dianhydride, methylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,2-ethylidene-4,4'-bis(cyclohexane-1 , 2-dicarboxylic acid) dianhydride, 1,1-ethynylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 2,2-propylene-4, 4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-propylene-4,4'-bis( Cyclohexane-1,2-dicarboxylic acid) dianhydride, oxy-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, thio-4,4'-bis( Cyclohexane-1,2-dicarboxylic acid) dianhydride, sulfonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 3,3'-difluorooxy -4,4'-diphthalic acid dianhydride, 5,5'-difluorooxy-4,4'-diphthalic acid dianhydride, 6,6'-difluorooxy-4,4'-diphthalein Acid dianhydride, 3,3',5,5',6,6'-hexafluorooxy-4,4'-diphthalic acid dianhydride, 3,3'-bis(trifluoromethyl)oxy- 4,4'-Diphthalic dianhydride, 5,5'-bis(trifluoromethyl)oxy-4,4'-diphthalic dianhydride, 6,6'-bis(trifluoromethyl)oxy base-4,4'-diphthalic dianhydride, 3,3',5,5'-tetra(trifluoromethyl)oxy-4,4'-diphthalic dianhydride, 3,3',6 ,6'-4(trifluoromethyl)oxy-4,4'-diphthalic acid dianhydride, 5 ,5',6,6'-4(trifluoromethyl)oxy-4,4'-diphthalic acid dianhydride, 3,3',5,5',6,6'-lu(trifluoromethyl) base)oxy-4,4'-diphthalic dianhydride, 3,3'-difluorosulfonyl-4,4'-diphthalic dianhydride, 5,5'-difluorosulfonyl-4 ,4'-diphthalic acid dianhydride, 6,6'-difluorosulfonyl-4,4'-diphthalic acid dianhydride, 3,3',5,5',6,6'-hexafluorosulfonic acid Acyl-4,4'-diphthalic dianhydride, 3,3'-bis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride, 5,5'-bis(trifluoromethyl) Methyl)sulfonyl-4,4'-diphthalic dianhydride, 6,6'-bis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride, 3,3', 5,5'-4(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride, 3,3',6,6'-4(trifluoromethyl)sulfonyl-4, 4'-diphthalic acid dianhydride, 5,5',6,6'-tetra(trifluoromethyl)sulfonyl-4,4'-diphthalic acid dianhydride, 3,3',5,5' ,6,6'-Lu(trifluoromethyl)sulfonyl-4,4'-diphthalic acid dianhydride, 3,3'-difluoro-2,2-perfluoropropylene-4,4' -Diphthalic dianhydride, 5,5'-difluoro-2,2-perfluoropropylene-4,4'-diphthalic dianhydride, 6,6'-difluoro-2,2-perfluoro Propylene-4,4'-diphthalic acid dianhydride, 3,3',5,5',6,6'-hexafluoro-2,2-perfluoropropylene-4,4'-diphthalide Acid dianhydride, 3,3'-bis(trifluoromethyl)-2,2-perfluoropropylene-4,4'-diphthalic acid dianhydride, 5,5'-bis(trifluoromethyl) -2,2-Perfluoropropylene-4,4'-diphthalic acid dianhydride, 6,6'-difluoro-2,2-perfluoropropylene-4,4'-diphthalic acid dianhydride , 3,3',5,5'-4(trifluoromethyl)-2,2-perfluoropropylene-4,4'-diphthalic dianhydride, 3,3',6,6'- 4(trifluoromethyl)-2,2-perfluoropropylene-4,4'-diphthalic dianhydride, 5,5',6,6'-4(trifluoromethyl)-2,2 -Perfluoropropylene-4,4'-diphthalic acid dianhydride, 3,3',5,5',6,6'-lu(trifluoromethyl)-2,2-perfluoropropylene -4,4'-Diphthalic dianhydride, 9-phenyl-9-(trifluoromethyl)xanthene-2,3,6,7-tetracarboxylic dianhydride, 9,9-bis(trifluoromethyl) Methyl)xanthene-2,3,6,7-tetracarboxylic dianhydride, bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 9, 9-bis[4-(3,4-dicarboxy)phenyl]indium dianhydride, 9,9-bis[4-(2,3-dicarboxy)phenyl]indium anhydride, ethylene glycol bis-triphenylene Triformate dianhydride, 1,2-(ethylidene)bis(trimellitic acid anhydride), 1,3-(trimethylene)bis(trimellitic acid anhydride), 1,4-(tetramellitic acid anhydride) Methylene)bis(trimellitic anhydride), 1,5-(pentamethylene)bis(trimellitic anhydride), 1,6-(hexamethylene Methyl)bis(trimellitic anhydride), 1,7-(heptamethylene)bis(trimellitic anhydride), 1,8-(octamethylene)bis(trimellitic acid) anhydride), 1,9-(nonamethylene)bis(trimellitic anhydride), 1,10-(decamethylene)bis(trimellitic anhydride), 1,12-(dodecyl anhydride) Methylene)bis(trimellitic anhydride), 1,16-(hexamethylene)bis(trimellitic anhydride), 1,18-(octadecylidene)bis(triphenylene) Triformic anhydride) etc. As a tricarboxylic acid anhydride, a trimellitic acid anhydride, a nuclear hydrogenated trimellitic acid anhydride, etc. are mentioned, for example.

As the amine component, diamines such as aliphatic diamines or aromatic diamines, polyvalent amines such as aliphatic polyetheramines, diamines having carboxylic acids, diamines having phenolic hydroxyl groups, etc. can be used, but not are restricted to these amines. In addition, these amine components can be used individually or in combination.

As the diamine, for example, p-phenylene diamine (PPD), 1,3-diaminobenzene, 2,4-toluenediamine, 2,5-toluenediamine, and 2,6-toluene can be mentioned. Diamines with one benzene nucleus such as diamines, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether Diaminodiphenyl ethers, 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diaminobiphenyl Methyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4 '-Diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, bis(4-aminophenyl)sulfide, 4 ,4'-Diaminobenzidine, 3,3'-dichlorobenzidine, 3,3'-dimethylbenzidine (o-tolidine), 2,2'-dimethylbenzidine (m-bitoluidine), 3,3'-dimethoxybenzidine, 2,2'-dimethoxybenzidine, 3,3'-diaminodiphenyl ether, 3,4'- Diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4 ,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl Di, 3,3'-diaminobenzophenone, 3,3'-diamino-4,4'-dichlorobenzophenone, 3,3'-diamino-4,4'- Dimethoxybenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 2, 2-bis(3-aminophenyl)propane, 2,2-bis(4-aminophenyl)propane, 2,2-bis(3-aminophenyl)-1,1,1,3, 3,3-hexafluoropropane, 2,2-bis(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 3,3'-diaminodiphenylene Diphenylene, 3,4'-diaminodiphenylene, 4,4'-diaminodiphenylene, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane Diamine with 2 benzene cores, 1,3-bis(3-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(3-aminophenyl)benzene phenyl)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy) Benzene, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)-4-trifluoromethylbenzene, 3,3'-diamino- 4-(4-phenyl)phenoxybenzophenone, 3,3'-diamino-4,4'-bis(4-phenylphenoxy)benzophenone, 1,3-bis (3-aminophenyl sulfide)benzene, 1,3-bis(4-aminophenylsulfide)benzene, 1,4-bis(4-aminophenylsulfide)benzene, 1,3- Bis(3-aminophenylbenzene)benzene, 1,3-bis(4-aminobenzene) phenyl)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis[2-(4-aminophenyl)isopropyl]benzene, 1,4-bis[2 -(3-aminophenyl)isopropyl]benzene, 1,4-bis[2-(4-aminophenyl)isopropyl]benzene and other diamines with three benzene nuclei, 3,3' -Bis(3-aminophenoxy)biphenyl, 3,3'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, bis[3-(3-aminophenoxy)phenyl]ether, bis[3-(4-aminophenoxy)benzene base] ether, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl]ether, bis[3-(3-aminobenzene] oxy)phenyl]ketone, bis[3-(4-aminophenoxy)phenyl]ketone, bis[4-(3-aminophenoxy)phenyl]ketone, bis[4-(4 -aminophenoxy)phenyl]ketone, bis[3-(3-aminophenoxy)phenyl]sulfide, bis[3-(4-aminophenoxy)phenyl]sulfide, bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-(4-aminophenoxy)phenyl]sulfide, bis[3-(3-aminophenoxy) ) phenyl] bismuth, bis[3-(4-aminophenoxy)phenyl] bis[4-(3-aminophenoxy)phenyl] bis[4-(4-amine) bis[3-(3-aminophenoxy)phenyl]methane, bis[3-(4-aminophenoxy)phenyl]methane, bis[4- (3-aminophenoxy)phenyl]methane, bis[4-(4-aminophenoxy)phenyl]methane, 2,2-bis[3-(3-aminophenoxy)benzene phenyl] propane, 2,2-bis[3-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2, 2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3 ,3-hexafluoropropane, 2,2-bis[3-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 2,2-bis[ 4-(3-Aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl] ]-1,1,1,3,3,3-Hexafluoropropane etc. 4-benzene nucleus Diamine etc. Aromatic diamine, 1,2-diaminoethane, 1,3-diamino Propane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane Alkane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,2-diamine Aliphatic diamines such as cyclohexane and the like include polyvalent amines of ethylene glycol and/or propylene glycol as the aliphatic polyether amine.

Examples of the amine having a carboxyl group include diaminobenzoic acids such as 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, and 3,4-diaminobenzoic acid, 3,5-diaminobenzoic acid, and the like. -Aminophenoxybenzoic acids such as bis(3-aminophenoxy)benzoic acid, 3,5-bis(4-aminophenoxy)benzoic acid, 3,3'-diamino-4 ,4'-dicarboxybiphenyl, 4,4'-diamino-3,3'-dicarboxybiphenyl, 4,4'-diamino-2,2'-dicarboxybiphenyl, 4,4 '-Diamino-2,2',5,5'-tetracarboxybiphenyl and other carboxybiphenyl compounds, 3,3'-diamino-4,4'-dicarboxydiphenylmethane , 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 2,2-bis[3-amino-4-carboxyphenyl]propane, 2,2-bis[4-amine yl-3-carboxyphenyl]propane, 2,2-bis[3-amino-4-carboxyphenyl]hexafluoropropane, 4,4'-diamino-2,2',5,5'- Carboxydiphenylalkanes such as carboxydiphenylmethane such as tetracarboxydiphenylmethane, 3,3'-diamino-4,4'-dicarboxydiphenyl ether, 4,4'-diamine Base-3,3'-dicarboxydiphenyl ether, 4,4'-diamino-2,2'-dicarboxydiphenyl ether, 4,4'-diamino-2,2',5 Carboxydiphenyl ether compounds such as ,5'-tetracarboxydiphenyl ether, 3,3'-diamino-4,4'-dicarboxydiphenyl ether, 4,4'-diamino-3 ,3'-Dicarboxydiphenylene, 4,4'-Diamino-2,2'-dicarboxydiphenylene, 4,4'-Diamino-2,2',5,5' -Diphenylene compounds such as tetracarboxydiphenylene and bis[(carboxyphenyl)benzene such as 2,2-bis[4-(4-amino-3-carboxyphenoxy)phenyl]propane yl]alkane compounds, bis[(carboxyphenoxy)phenyl]thiane compounds such as 2,2-bis[4-(4-amino-3-carboxyphenoxy)phenyl]thiazide, and the like.

As the isocyanate component, diisocyanates such as aromatic diisocyanates and their isomers or polymers, aliphatic diisocyanates, alicyclic diisocyanates and their isomers, etc., or other general-purpose diisocyanates can be used. , but not limited to those isocyanates. In addition, these isocyanate components can be used individually or in combination.

As the diisocyanate, for example, 4,4'-diphenylmethane diisocyanate, tolyl diisocyanate, naphthalene diisocyanate, diphenyl diisocyanate, biphenyl diisocyanate, diphenyl diisocyanate , Aromatic diisocyanates such as diphenyl ether diisocyanate and their isomers, polymers, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate and other aliphatic diisocyanates , or alicyclic diisocyanates and isomers obtained by hydrogenating the aforementioned aromatic diisocyanates, or other commonly used diisocyanates.

(3) Carboxyl group-containing resin having an amide structure but not having an amide structure Carboxyl group-containing resin having an amide structure but not having an amide structure is not particularly limited as long as it is a resin having a carboxyl group and an amide bond.

As explained above, the acid value of the carboxyl group-containing resin suitably used as the alkali-soluble resin of the present invention is preferably 20-200 mgKOH/g, preferably 60-150 mgKOH/g, in order to correspond to the photolithography step. When the acid value is 20 mgKOH/g or more, the solubility in alkalis increases, and the developability becomes good, and since the degree of crosslinking with the thermosetting component after light irradiation becomes high, sufficient contrast in development can be obtained. On the other hand, when the acid value is 200 mgKOH/g or less, it becomes easier to draw a correct pattern, and in particular, the so-called thermal blurring in the PEB (POST EXPOSURE BAKE) step after light irradiation, which will be described later, can be suppressed, and the process tolerance can be improved. get bigger.

In addition, when the molecular weight of such a carboxyl group-containing resin is considered, the mass average molecular weight Mw is preferably 100,000 or less, preferably 1,000 to 100,000, and more preferably 2,000 to 50,000. When this molecular weight is 100,000 or less, the alkali solubility of an unexposed part increases and developability improves. On the other hand, when the molecular weight is 1,000 or more, sufficient development resistance and curing properties can be obtained in the exposed part after exposure and PEB.

(Photopolymerization Initiator) As the photopolymerization initiator used in the resin layer (B), a well-known and customary one can be used, and especially when used in the PEB step after light irradiation, which will be described later, it is suitable to also have a photobase generated The function of the photopolymerization initiator. Furthermore, in this PEB step, a photopolymerization initiator and a photobase generator may be used in combination.

A photopolymerization initiator that also functions as a photobase generator is a compound that changes its molecular structure by irradiation with light such as ultraviolet rays or visible light, or generates energy by molecular cleavage. The function will be described later. One or more basic substances as catalysts for the polymerization reaction of thermally reactive compounds. As a basic substance, a secondary amine and a tertiary amine are mentioned, for example. As such a photopolymerization initiator which also functions as a photobase generator, for example, an α-aminoacetophenone compound, an oxime ester compound, or an amide oxyimino group, N-methyl amide compound can be mentioned. Compounds of substituents such as alkylated aromatic amine groups, N-arylated aromatic amine groups, nitrobenzyl carbamate groups, alkoxybenzyl carbamate groups, etc. Among them, oxime ester compounds and α-aminoacetophenone compounds are also preferred, and oxime ester compounds are preferred. As the α-aminoacetophenone compound, those having two or more nitrogen atoms are particularly preferred.

The α-aminoacetophenone compound should just be a basic substance (amine) which has a benzoin ether bond in the molecule, and is cleaved in the molecule when irradiated with light to achieve the effect of a hardening catalyst.

As the oxime ester compound, any compound can be used as long as it is a compound that generates a basic substance by light irradiation.

Such a photopolymerization initiator system may be used individually by 1 type, and may be used in combination of 2 or more types. The compounding amount of the photopolymerization initiator in the resin composition is preferably 0.1 to 40 parts by mass, more preferably 0.3 to 15 parts by mass, relative to 100 parts by mass of the alkali-soluble resin. In the case of 0.1 part by mass or more, the contrast of the development resistance of the light-irradiated part/unirradiated part can be obtained favorably. Moreover, when it is 40 mass parts or less, the hardened|cured material characteristic improves.

(Thermal Reactive Compound) As the thermally reactive compound, a known conventional compound having a functional group such as a cyclic (thio)ether group that can be hardened and reacted by heat, for example, an epoxy compound and the like can be used. As said epoxy compound, for example, bisphenol A type epoxy resin, brominated epoxy resin, novolac type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, glycidyl epoxy resin can be mentioned. Amine type epoxy resin, hydantoin type epoxy resin, alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, biphenol type or biphenol type epoxy resin or mixtures thereof; Bisphenol S type epoxy resin, bisphenol A novolac type epoxy resin, tetraphenol ethane type epoxy resin, heterocyclic epoxy resin, diglycidyl phthalate resin, tetra epoxy resin Propylxylyl ethane resin, epoxy resin containing naphthyl group, epoxy resin with dicyclopentadiene skeleton, glycidyl methacrylate copolymer epoxy resin, cyclohexylmalein Copolymerized epoxy resin of imine and glycidyl methacrylate, CTBN modified epoxy resin, etc.

As the compounding amount of the above-mentioned thermally reactive compound, the equivalent ratio to the alkali-soluble resin (alkali-soluble groups such as carboxyl groups: thermally reactive groups such as epoxy groups) is preferably 1:0.1 to 1:10. By setting such a mixing ratio in the range, development becomes favorable, and a fine pattern can be easily formed. The above-mentioned equivalent ratio is preferably 1:0.2~1:5.

(Block Copolymer) In order to balance the flexibility of achieving the above-mentioned flexibility, especially excellent crack resistance against excessive folding, and excellent heat resistance, the block copolymer is used in the resin layer constituting the laminated structure of the present invention. The most characteristic ingredient in (B). As this block copolymer, it generally refers to a copolymer in which two or more types of polymer units with different properties are linked by covalent bonds to form a long-chain molecular structure. In the present invention, as the block copolymer, well-known and conventional ones can be used, and X-Y-type or X-Y-X-type block copolymers are preferable, and X-Y-X-type block copolymers are more preferable. X in the X-Y-X type block copolymer may be the same or different.

In addition, in the X-Y type or X-Y-X type block copolymer, X is preferably a polymer unit whose glass transition temperature Tg is 0°C or higher. Preferably, X is a polymer unit having a glass transition temperature Tg of 50°C or higher. In addition, Y is preferably a polymer unit whose glass transition temperature Tg is less than 0°C, preferably a polymer unit whose glass transition temperature Tg is -20°C or less. The glass transition temperature Tg can be measured by differential scanning calorimetry (DSC).

The block copolymer is preferably solid at 20-30°C. In this case, it is only necessary to be solid within this range, and it may be solid at a temperature outside this range. By being solid in the above-mentioned temperature range, it becomes one with excellent viscosity after dry film formation or after being applied to a substrate and temporarily dried.

In addition, among the X-Y-X type block copolymers, X is preferably one with high compatibility with the thermally reactive compound, and Y is preferably one with low compatibility with the thermally reactive compound. Therefore, it is considered that by making the blocks at both ends compatible with the matrix and the block in the center incompatible with the block copolymer in the matrix, it is considered that a specific structure can be easily developed in the matrix.

As the polymer unit X, polymethacrylate (PMMA), polystyrene (PS), etc. are preferred, and as the polymer unit Y, polyn-butyl (meth)acrylate (PBA), Polybutadiene (PB) and the like are preferred. In addition, a portion of the polymer unit X, represented by a styrene unit, a hydroxyl group-containing unit, a carboxyl group-containing unit, an epoxy group-containing unit, an N-substituted acrylamide unit, etc., is introduced into a portion of the polymer unit X, which is excellent in compatibility with alkali-soluble resins. When the sex unit is used, it becomes more able to improve the compatibility. It is particularly preferable to introduce an epoxy group-containing unit to a part of the polymer unit X. Among the above, the polymer unit X is also made of polystyrene, polyglycidyl methacrylate, or N-substituted polyacrylamide, polymethyl (meth)acrylate or its carboxylic acid denatured product or hydrophilic group. Denatures are preferred. Moreover, as Y series, poly-n-butyl (meth)acrylate, polybutadiene, etc. are preferable. X and Y may each be constituted by one kind of polymer unit, or may be constituted by a polymer unit obtained from two or more kinds of components.

As a method for producing a block copolymer, for example, the methods described in JP 2005-515281 A and JP 2007-516326 A can be mentioned.

As a commercial item of the X-Y-X type block copolymer, for example, an acryl-based triblock copolymer produced by using living polymerization manufactured by Arkema can be mentioned. As this specific example, X-Y-X type block copolymers (for example, M51, M52, M53, M22) represented by polymethacrylate-polybutylacrylate-polymethmethacrylate can be mentioned. etc.), and X-Y-X type block copolymers (eg, SM4032XM10, etc.) denatured by carboxylic acid, or X-Y-X type block copolymers (eg, M52N, M22N, M65N, etc.) denatured by hydrophilic groups.

In addition, the mass average molecular weight (Mw) of the block copolymer is usually 20,000 to 400,000, preferably in the range of 30,000 to 300,000. The molecular weight distribution (Mw/Mn) is preferably 3 or less.

When the mass average molecular weight is 20,000 or more, the composition has mechanical properties such as softness and elasticity, and the adhesiveness does not become too high, the effect of improving the bending and crack resistance becomes good, and the viscosity also becomes good. On the other hand, when the mass average molecular weight is 400,000 or less, the viscosity of the composition does not become high, and the printability and the developability are less likely to decrease.

A block copolymer may be used individually by 1 type, and may be used in combination of 2 or more types. The blending amount of the block copolymer is preferably 1 to 60 parts by mass, preferably 2 to 50 parts by mass, and particularly preferably 3 to 40 parts by mass relative to 100 parts by mass of the alkali-soluble resin. When the compounding amount of the block copolymer is 1 part by mass or more, the flexibility and heat resistance are improved, and when it is 60 parts by mass or less, the balance of the flexibility and heat resistance becomes favorable.

In the resin composition used for the resin layer (A) and the resin layer (B) described above, the following components can be blended as necessary.

(Polymer resin) The polymer resin is used for the purpose of improving the flexibility and dryness to the touch of the obtained cured product, and known and conventional ones other than the above-mentioned block copolymer can be blended. Examples of such polymer resins include cellulose-based, polyester-based, phenoxy resin-based polymers, polyvinylacetal-based, polyvinylbutyral-based, polyamide-based, and polyamide amides. Amine adhesive polymers, elastomers, etc. This polymer resin system may be used individually by 1 type, and may use 2 or more types together.

(Inorganic fillers) Inorganic fillers are those that can be blended in order to suppress the hardening shrinkage of the cured product and improve the properties such as adhesion and hardness. Examples of such inorganic fillers include barium sulfate, amorphous silica, molten silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, nitrogen Silicon, aluminum nitride, boron nitride, Neuburg Silicious earth, etc.

(Coloring agent) As the coloring agent, well-known and customary coloring agents such as red, blue, green, yellow, white, black, etc. can be blended, and any of pigments, dyes, and pigments can be used.

(Organic solvent) An organic solvent can be blended in order to prepare a resin composition, or to coat a substrate or a carrier film in order to adjust the viscosity. Examples of such organic solvents include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, and petroleum-based solvents. Such an organic solvent may be used individually by 1 type, and may be used as a mixture of 2 or more types.

(Other components) If necessary, components such as mercapto compounds, adhesion promoters, antioxidants, ultraviolet absorbers, etc. can also be blended. For these systems, well-known ones can be used. In addition, it can be mixed with well-known and commonly used thickeners such as micropowder silica, hydrotalcite, organic bentonite, montmorillonite, etc., such as polysiloxane-based, fluorine-based, polymer-based antifoaming agents and/or leveling agents well-known and commonly used additives such as anti-corrosion agents, silane coupling agents, and rust inhibitors.

Since the laminated structure of the present invention is excellent in flexibility, it can be used for at least any one of the curved portion and the non-curved portion of a flexible printed wiring board, and can also be used as a coating for a flexible printed wiring board. At least any one of layers, solder resists and interlayer insulating materials.

The laminate structure of the present invention having the above-described constitution is preferably used as a dry film whose at least one side is supported or protected by a film.

(Dry film) The dry film system of the present invention can be produced, for example, by the following operations. That is, first, on the carrier film (supporting film), the composition constituting the above-mentioned resin layer (B) and the composition constituting the resin layer (A) are respectively diluted with an organic solvent to adjust the viscosity to an appropriate viscosity. It coats sequentially by well-known methods, such as a comma coater. Thereafter, by drying at a temperature of usually 50 to 130° C. for 1 to 30 minutes, a dry film composed of the resin layer (B) and the resin layer (A) can be formed on the carrier film. For the purpose of preventing dust from adhering to the surface of the film, a peelable cover film (protective film) can be further laminated on the dry film. As the carrier film and the cover film, a conventionally known plastic film can be suitably used, and the cover film is preferably one with a smaller adhesive force between the resin layer and the carrier film when the cover film is peeled off. The thicknesses of the carrier film and the cover film are not particularly limited, and are generally appropriately selected within the range of 10 to 150 μm.

(Flexible Printed Wiring Board) The flexible printed wiring board of the present invention has a layer in which the laminate structure of the present invention is formed on a flexible printed wiring substrate, patterned by light irradiation, and displayed on the display. An insulating film formed by forming a pattern in an image solution at one time.

(Manufacturing method of wiring board) The manufacturing of the flexible printed wiring board using the laminated structure of the present invention can be carried out in accordance with the operation sequence shown in the step diagram of FIG. 1 . That is, the manufacturing method includes: a step (lamination step) of forming a layer of the laminate structure of the present invention on a flexible wiring substrate on which a conductor circuit has been formed; applying an active energy ray to the layer of the laminate structure A step of irradiating into a patterned shape (exposure step), and a step of forming the layer of the patterned laminate structure at one time (developing step) by subjecting the layer of the laminated structure to alkali development. Furthermore, if necessary, after alkali development, further photocuring or thermal curing (post-curing step) is performed to completely cure the layers of the laminate structure, and a highly reliable flexible printed wiring board can be obtained.

Moreover, the manufacture of the flexible printed wiring board using the laminated structure of this invention can also be performed using the operation sequence shown in the step diagram of FIG. That is, the manufacturing method includes: a step (lamination step) of forming a layer of the laminate structure of the present invention on a flexible wiring substrate on which a conductor circuit has been formed; applying an active energy ray to the layer of the laminate structure A step of irradiating into a patterned shape (exposure step), a step of heating the layer of the laminate structure (heating (PEB) step), and the layer of the laminate structure is subjected to alkali development to form a patterned The step of patterning the layers of the laminated structure (development step). In addition, if necessary, after alkali development, further photo-curing or thermal curing (post-curing step) is performed to completely cure the layers of the laminated structure, and a highly reliable flexible printed wiring board can be obtained. In particular, in the case of using a carboxyl group-containing resin having at least one of an imide structure and an imide structure in the resin layer (B), it is preferable to use the operation sequence shown in the step diagram of FIG. 2 .

Hereinafter, each step shown in FIG. 1 or FIG. 2 will be described in detail. [Lamination step] In this step, on the flexible printed wiring substrate 1 having the conductor circuit 2, a laminated structure is formed, and the laminated structure is composed of the resin layer 3 (resin layer (A)), and The resin layer 4 (resin layer (B)) on the resin layer 3 is composed of an alkali-developing resin composition containing an alkali-soluble resin or the like, and the resin layer 4 is composed of an alkali-containing resin composition. It is composed of a photosensitive thermosetting resin composition such as a soluble resin. Here, each resin layer constituting the laminated structure can be formed by, for example, sequentially applying the resin composition constituting the resin layers 3 and 4 to the wiring substrate 1 and drying to form the resin layers 3 and 4, or, alternatively, It can be formed by a method of laminating the resin composition constituting the resin layers 3 and 4 in the form of a dry film having a two-layer structure on the wiring substrate 1 .

The coating method of applying the resin composition to the wiring substrate may be a known method such as a blade coater, a lip coater, a comma coater, or a film coater. In addition, the drying method is to use a hot air circulation type drying furnace, IR furnace, hot plate, convection oven, etc., if there is a heat source of the heating method formed by steam, a method of making the hot air in the dryer countercurrent contact, and a nozzle through a nozzle A known method such as a method of blowing onto a support.

As a method of laminating the resin composition on the wiring base material, it is preferable to perform lamination under pressure and heating using a vacuum laminator or the like. By using such a vacuum laminator, even if the surface of the wiring substrate has irregularities, the dry film is adhered to the wiring substrate, so air bubbles are not mixed in, and the buried hole property of the recessed portion on the surface of the wiring substrate is improved. . The pressure conditions are preferably about 0.1 to 2.0 MPa, and the heating conditions are preferably 40 to 120°C.

[Exposure step] This step is to activate the photopolymerization initiator contained in the resin layer 4 into a negative pattern by irradiating active energy rays, thereby curing the exposed portion. In the case of a composition using the PEB step described later, a photopolymerization initiator or a photobase generator having a function as a photobase generator is activated in a negative pattern to generate a base. As the exposure machine used in this step, a direct drawing device, an exposure machine equipped with a metal halide lamp, etc. can be used. The pattern-shaped exposure mask is a negative mask.

As the active energy ray used for exposure, it is preferable to use laser light or scattered light with a maximum wavelength in the range of 350-450 nm. By setting the maximum wavelength in this range, the photopolymerization initiator can be efficiently activated. In addition, although the exposure amount differs depending on the film thickness, etc., it is usually 100 to 1500 mJ/cm ² .

[PEB step] This step is to harden the exposed portion by heating the resin layer after exposure. By this step, a photopolymerization initiator having a function as a photobase generator is used, or an exposure step of the resin layer (B) constituted by a combination of a photopolymerization initiator and a photobase generator is used. The alkali generated in the resin layer (B) can be hardened to the deep part. The heating temperature is, for example, 80 to 140°C. The heating time is, for example, 10 to 100 minutes. Since the curing of the resin composition of the present invention is, for example, a ring-opening reaction of an epoxy resin due to a thermal reaction, distortion and curing shrinkage can be suppressed compared to the case where curing proceeds by a photoradical reaction.

[Development step] This step is to remove the unexposed portion by alkali development, and form a negative patterned insulating film, especially to form a cladding layer and a solder resist. As the developing method, a known method such as dipping can be used. Also, as the developing solution, an alkaline aqueous solution such as sodium carbonate, potassium carbonate, potassium hydroxide, amines, imidazoles such as 2-methylimidazole, aqueous tetramethylammonium hydroxide (TMAH) or the like can be used, or the etc. mixture.

[Post-curing step] After the developing step, the insulating film is completely thermally cured to obtain a highly reliable coating film. The heating temperature is, for example, 120°C to 180°C. The heating time is, for example, 5 minutes to 120 minutes. Furthermore, light irradiation may also be applied to the insulating film before or after post-curing. [Example]

Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples, but the present invention is not limited by these Examples and Comparative Examples.

<Synthesis Example 1: Synthesis Example of Polyimide Resin Solution> 3,3'-diamino-4,4' was added to a separable three-necked flask equipped with a stirrer, nitrogen introduction tube, fractionation ring, and cooling ring. - 22.4 g of dihydroxydiphenylene, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane 8.2 g, 30 g of NMP, 30 g of γ-butyrolactone, 4,4'- 27.9 g of oxydiphthalic anhydride and 3.8 g of trimellitic anhydride were stirred at room temperature for 4 hours at 100 rpm in a nitrogen atmosphere. Next, 20 g of toluene was added, and toluene and water were distilled off at a silicon bath temperature of 180° C. and 150 rpm while stirring for 4 hours to obtain a polyimide resin solution (PI-1) having a phenolic hydroxyl group and a carboxyl group. The acid value of the obtained resin (solid content) was 18 mgKOH, the Mw was 10,000, and the hydroxyl equivalent was 390.

(Examples 1 to 6 and Comparative Examples 1 to 4) According to the composition of ingredients described in Table 1 and Table 2, the materials described in Examples 1 to 6 and Comparative Examples 1 to 4 were individually mixed, and after preliminary mixing in a mixer, 3 The back-roller kneads it, and prepares the resin composition which forms each resin layer. The value in the table is the mass part of solid content unless otherwise specified.

<Formation of resin layer (A)> A flexible printed wiring substrate with a copper thickness of 18 μm formed circuit was prepared, and pretreatment was performed using CZ-8100 from MEC Corporation. Thereafter, the resin compositions constituting the respective resin layers (A) obtained in Examples 1 to 6 and Comparative Examples 1 to 4 were applied to the pre-treated flexible resin compositions so that the film thickness after drying would be 25 μm, respectively. printed wiring substrate. Then, the resin layer (A) was formed by drying at 90° C./30 minutes in a hot air circulation type drying furnace.

<Formation of the resin layer (B)> The resin compositions constituting the respective resin layers (B) obtained in Examples 1 to 6 and Comparative Examples 1 to 4 were applied to the above-mentioned resin compositions so that the film thickness after drying would be 10 μm. on the formed resin layer (A). Then, the resin layer (B) was formed by drying at 90° C./30 minutes in a hot air circulation type drying furnace.

By this operation, the uncured laminate structure composed of the resin layer (A) and the resin layer (B) described in Examples 1 to 6 and Comparative Examples 1 to 4 was formed on the flexible printed wiring substrate.

<Flexibility> (Preparation of Test Piece) For the uncured laminate structure on each flexible printed wiring substrate on which the laminate structure was formed by the above operation, first, an exposure apparatus equipped with a metal halide lamp was used. (HMW-680-GW20), full exposure at 500 mJ/cm ² through a negative mask. Then, after the PEB step was performed at 90° C. for 30 minutes, by performing development (30° C., 0.2 MPa, 1 mass % Na ₂ CO ₃ aqueous solution) for 60 seconds, and thermally hardening at 150° C.×60 minutes, it was produced. A flexible printed wiring board having a cured laminate structure formed thereon. And this flexible printed wiring board was cut|disconnected to about 15 mm x about 110 mm, and it was set as a test piece.

(MIT test) Each of the obtained test pieces was subjected to an MIT test according to JIS P8115 using an MIT folding fatigue tester D type (manufactured by Toyo Seiki Co., Ltd.) to evaluate the flexibility. Specifically, as shown in FIG. 3 , the test piece 10 is mounted on the device, and the test piece 10 is vertically mounted on the jig 11 in a state where the load F (0.5 kgf) is loaded, and the bending angle α is 135 Bending at a speed of 175cpm, and measure the number of round-trip bending (times) until it breaks. Furthermore, the test environment was 25°C. The evaluation criteria are as follows. ◎: Bending more than 200 times, no cracks appeared in the hardened coating film at the bending place. 〇: Bending 170 to 199 times, no cracks appear. △: Bending 150~169 times, and no cracks appeared. ×: The number of bending times is less than 149 times, but cracks appear.

(Reduced test) Furthermore, the bending properties of each of the obtained test pieces were evaluated when subjected to the reduced test under the excessively severe conditions shown below. Specifically, as shown in FIG. 4 , a load is applied between two flat plates 12 in a state where the conductor circuit of the test piece 10 and the forming surface X of the cured coating film are turned to the outside and are bent at 180°. G (1kg of standard copper) After 10 seconds and folding, use an optical microscope to confirm whether cracks are generated on the hardened coating part 20 at the bending place as 1 cycle, and record the number of times before cracks occur. The test environment is 25°C. The evaluation criteria are as follows. ◎: Bending more than 10 times, no cracks occurred in the hardened coating film at the bending place. 〇: Bending 6 to 9 times, no cracks were produced. △: Bending 3 to 5 times, no cracks were produced. ×: Cracks occurred when the number of bending times was 2 or less. The results of these evaluations are combined and shown in Table 1 and Table 2.

<Heat resistance> For the uncured laminate structure on each flexible printed wiring substrate on which the laminate structure was formed by the above operation, first, an exposure apparatus (HMW-680-GW20) equipped with a metal halide lamp was used. ), exposed on the copper at 500mJ/cm ² through a negative mask with an opening of about 2mm to 5mm in diameter. Then, after the PEB step was performed at 90° C. for 30 minutes, by performing development (30° C., 0.2 MPa, 1 mass % Na ₂ CO ₃ aqueous solution) for 60 seconds, and thermally hardening at 150° C.×60 minutes, it was produced. The flexible printed wiring board (test board) of the cured laminate structure has been formed.

This test substrate was coated with a rosin-based flux, and immersed in a solder tank preset at 260° C. and 280° C. to evaluate the occurrence of floating, swelling, and peeling of the cured coating film. The evaluation criteria are as follows. ◎: No floating, swelling and peeling occurred in either immersion at 260°C and 280°C. 〇: Although no floating, swelling and peeling occurred during immersion at 260°C, floating, swelling and peeling occurred during immersion at 280°C. ×: Floating and peeling occurred in either immersion at 260°C or 280°C. The evaluation results are combined in Table 1 and Table 2.

<Resolution> For the uncured laminate structure on each flexible printed wiring substrate on which the laminate structure was formed by the above operation, first, an exposure apparatus (HMW-680-GW20) equipped with a metal halide lamp was used. ), through a negative mask, pattern exposure was performed at 500 mJ/cm ² in such a way that an opening with a diameter of 200 μm would be formed. After that, after the PEB step was performed at 90°C for 30 minutes, the pattern was drawn by performing development (30°C, 0.2 MPa, 1 mass % Na ₂ CO ₃ aqueous solution) for 60 seconds, and heated at 150° C. × 60 minutes. It is hardened, and the flexible printed wiring board which forms the hardened laminated structure which has an opening is produced. The opening formed in the laminated structure of the obtained flexible printed wiring board was observed using the optical microscope adjusted to 100 times, and the resolution was evaluated. The evaluation criteria are as follows. 〇: The opening is completely formed. ×: The opening is not formed. The evaluation results are combined and shown in Table 1 and Table 2.

＊1)鹼溶解性樹脂1：　ZAR-1035：酸變性雙酚A型環氧丙烯酸酯，酸價98mgKOH／g(日本化藥(股)製) ＊2)聚醯亞胺樹脂：　PI-1：合成例1 ＊3)光硬化性單體：　BPE-500：乙氧基化雙酚A二甲基丙烯酸酯(新中村化學(股)製) ＊4)環氧樹脂：　E828：雙酚A型環氧樹脂，環氧當量190，質量平均分子量380(三菱化學(股)製) ＊5)光聚合起始劑：　IRGACURE　OXE02：肟系光聚合起始劑(BASF公司製) ＊6)嵌段共聚物1：　M52N：X-Y-X型嵌段共聚物　質量平均分子量(Mw)約100,000、阿科瑪公司製、NANOSTRENGTH(註冊商標) ＊7)嵌段共聚物2：　M65N：X-Y-X型嵌段共聚物　質量平均分子量(Mw)約100,000~300,000、阿科瑪公司製,NANOSTRENGTH(註冊商標) ＊8)鹼溶解性樹脂2：　P7-532：聚胺基甲酸酯丙烯酸酯，酸價47mgKOH／g(共榮社化學(股)製)

*1) Alkali-soluble resin 1: ZAR-1035: acid-denatured bisphenol A type epoxy acrylate, acid value 98 mgKOH/g (manufactured by Nippon Kayaku Co., Ltd.) *2) Polyimide resin: PI-1 : Synthesis example 1 *3) Photocurable monomer: BPE-500: Ethoxylated bisphenol A dimethacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) *4) Epoxy resin: E828: Bisphenol A Type epoxy resin, epoxy equivalent 190, mass average molecular weight 380 (manufactured by Mitsubishi Chemical Corporation) *5) Photopolymerization initiator: IRGACURE OXE02: Oxime-based photopolymerization initiator (manufactured by BASF Corporation) *6) Embedded Block copolymer 1: M52N: XYX type block copolymer Mass average molecular weight (Mw) about 100,000, manufactured by Arkema Corporation, NANOSTRENGTH (registered trademark) *7) Block copolymer 2: M65N: XYX type block copolymer substance Weight average molecular weight (Mw) about 100,000 to 300,000, manufactured by Arkema, NANOSTRENGTH (registered trademark) *8) Alkali-soluble resin 2: P7-532: Polyurethane acrylate, acid value 47 mgKOH/g ( Kyoeisha Chemical (stock)

From the evaluation results shown in the above table, it can be seen that in the laminate structures of the respective examples, the resin layer (B) on the upper layer side contains the block copolymer, and the flexibility, heat resistance and resolution are improved. Any one of them can achieve excellent performance. On the other hand, in Comparative Example 1 and Comparative Example 2 of the single-layer structure, the flexibility, especially the excellent crack resistance against excessive folding, was insufficient, and even in the case of the laminated structure but not containing the block copolymer. In Comparative Example 3, although good results were obtained in terms of heat resistance, the flexibility, especially the excellent crack resistance against excessive folding, was insufficient. In addition, in Comparative Example 4 in which only the resin layer (A) on the lower layer side of the laminate structure contained the block copolymer, good results were obtained in terms of heat resistance, but in terms of flexibility, it was particularly difficult for excessive folding. Excellent crack resistance and resolution are not sufficient. From the above, in the laminated structure formed by laminating two resin layers, the resin layer (B) on the upper layer side contains the block copolymer, so that the photosensitive resin composition itself can maintain the resolution, etc. It can improve the bending properties in a well-balanced manner, especially the excellent crack resistance and heat resistance against excessive folding.

1‧‧‧Flexible printed wiring substrate 2‧‧‧Conductor circuit 3‧‧‧Resin layer 4‧‧‧Resin layer 5‧‧‧Mask 10‧‧‧Test piece 11‧‧‧Clamp 12‧‧‧ Flat plate 20‧‧‧Curing coating part X‧‧‧Conductor circuit and curing coating forming surface

1 ] A step diagram schematically showing an example of the manufacturing method of the flexible printed wiring board of the present invention. [ Fig. 2 ] A step diagram schematically showing another example of the manufacturing method of the flexible printed wiring board of the present invention. [Fig. 3] A schematic explanatory diagram showing the MIT test of the Example. [Fig. 4] A schematic explanatory diagram showing the conversion test of the Example.

Claims (9)

A laminated structure comprising: a resin layer (A), and a resin layer (B) laminated on a flexible printed wiring board via the resin layer (A); wherein the resin layer ( B) is composed of a photosensitive thermosetting resin composition containing an alkali-soluble resin, a photopolymerization initiator, a thermally reactive compound, and a block copolymer, and the resin layer (A) is composed of an alkali-soluble resin composition It is composed of an alkali-developing resin composition of a reactive resin and a heat-reactive compound; the aforementioned block copolymer is of X-Y type or X-Y-X type, X is a polymer unit whose glass transition temperature Tg is above 0°C, and Y is glass transition temperature A polymer unit with Tg less than 0°C. The laminated structure of claim 1, wherein the aforementioned block copolymer is of type X-Y-X. The laminate structure according to claim 1 or 2, wherein the block copolymer has a mass average molecular weight (Mw) of 20,000 to 400,000. The laminated structure according to claim 1 or 2, wherein a photobase generator is contained as a photopolymerization initiator of the aforementioned resin layer (B). The laminate structure according to claim 1 or 2, wherein the resin layer (A) is composed of an alkali-developing resin composition that does not contain a photopolymerization initiator. The laminate structure according to claim 1 or 2, which is used in at least one of the curved portion and the non-curved portion of a flexible printed wiring board. The laminated structure according to claim 1 or 2 is used for at least any one of a coverlay, a solder resist, and an interlayer insulating material of a flexible printed wiring board. A dry film, characterized in that at least one side of the laminate structure according to any one of claims 1 to 7 is supported or protected by a film. A flexible printed wiring board characterized by having an insulating film using the laminate structure according to any one of claims 1 to 7.

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