KR102372561B1 - Photosensitive thermosetting resin composition and flexible printed circuit board - Google Patents

Abstract

The present invention provides a photosensitive thermosetting resin composition that is excellent in reliability such as impact resistance and flexibility, processing precision, and workability, and is suitable for the batch formation process of an insulating film of a flexible printed wiring board, especially a bent part (bent part) and a mounting part (non-bend part) intended to provide A photosensitive thermosetting resin composition comprising (A) a polyimide resin having an imide ring and a carboxyl group, (B) a resin having a phenolic hydroxyl group, (C) a photobase generator, and (D) a thermosetting component .

Description

A photosensitive thermosetting resin composition and a flexible printed wiring board TECHNICAL FIELD

The present invention relates to a photosensitive thermosetting resin composition and a flexible printed wiring board, and more particularly, photosensitivity that can be developed with alkali, has excellent heat resistance and flexibility, and is easy to manage temperature and time during heat curing after light irradiation It is related with the flexible printed wiring board provided with the hardened|cured material of a thermosetting resin composition and the said photosensitive thermosetting resin composition.

In recent years, the spread of smart phones or tablet terminals and improvement in performance are rapidly progressing. Information device terminals represented by these have high consumer demands for miniaturization and thinness, and in order to meet the demands, high density and space saving of circuit boards inside products are required. Therefore, the use of the flexible printed wiring board which can bend storage and can raise the freedom degree of circuit arrangement is expanding, and it is calculated|required that the reliability with respect to a flexible printed wiring board is also higher than before.

Currently, as an insulating film for securing insulation reliability of a flexible printed wiring board, a polyimide-based coverlay is used for the bent portion (bent portion), and a mixed process using a photosensitive resin composition is widely used for the mounting portion (non-bend portion). has been adopted (see Patent Documents 1 and 2). Polyimide is excellent in mechanical properties, such as heat resistance and flexibility, and on the other hand, the photosensitive resin composition used for the mounting part is excellent in electrical insulation, solder heat resistance, etc., and has the characteristic that microfabrication is possible.

Conventional polyimide-based coverlays are unsuitable for fine wiring because they require processing by die punching. Therefore, using together the photosensitive resin composition (solder resist) of the alkali development type in which the process by photolithography is possible is performed for the chip mounting part which requires fine wiring partially. In the manufacture of a flexible printed wiring board, when such a resin composition is partially used, two processes are passed: a process of bonding a coverlay and a process of forming a solder resist, so that the cost and workability are lowered. there was.

Japanese Patent Laid-Open No. 62-263692 Japanese Patent Laid-Open No. 63-110224

Therefore, conventionally, examination of the insulating film of the flexible printed wiring board which does not depend on a mixed process is made|formed. For example, although applying the photosensitive resin composition for soldering resists as a coverlay of a flexible printed wiring board is examined, with the resin composition for soldering resists, reliability, such as impact resistance and flexibility as a coverlay, is inadequate. In the resin composition for soldering resists, since curing shrinkage by acrylic photopolymerization was also accompanied, there existed a subject also in dimensional stability, such as the curvature of a flexible printed wiring board.

Also, as a photosensitive polyimide capable of achieving both alkali solubility and mechanical properties, a method of thermal ring closure after patterning using a polyimide precursor has been proposed, but there is a problem in workability such as requiring high-temperature treatment.

Therefore, an object of the present invention is to provide excellent reliability, processing precision, and workability such as impact resistance and flexibility, and photosensitivity suitable for the process of forming an insulating film of a flexible printed circuit board, particularly a bent portion (bent portion) and a mounting portion (non-bend portion). To provide a thermosetting resin composition.

As a result of earnest examination in order to solve the said subject, the present inventors discovered that the resin composition containing the polyimide resin which has a carboxyl group, a photobase generator, and a thermosetting component can solve the said subject.

That is, the photobase generator is activated by light irradiation, and the generated base is used as a catalyst, and the polyimide resin having a carboxyl group and the thermosetting component are subjected to an addition reaction by heating, so that only the unexposed portion is removed with an alkaline solution. found that it was possible. Thereby, while microfabrication by alkali development becomes possible, it is expectable to obtain the hardened|cured material excellent in reliability.

On the other hand, in the heat curing reaction after light irradiation, if the width of the heating temperature and heating time can be widened, the present inventors have found the following as a result of further studies from the viewpoint of providing a resin composition excellent in workability The present invention has been completed. That is, a photosensitive thermosetting resin composition comprising a polyimide resin having an imide ring, a carboxyl group and a phenolic hydroxyl group, or a photosensitive thermosetting resin composition comprising a polyimide resin having an imide ring and a carboxyl group and a resin having a phenolic hydroxyl group By setting it as this, in addition to the said characteristic, the photosensitive thermosetting resin composition excellent in workability|operativity can be obtained.

The present invention is the following [1] to [8].

[1] Photosensitive thermosetting comprising (A) a polyimide resin having an imide ring and a carboxyl group, (B) a resin having a phenolic hydroxyl group, (C) a photobase generator, and (D) a thermosetting component resin composition.

[2] The photosensitive thermosetting resin composition of [1], wherein the resin (B) further has an imide ring.

[3] The photosensitive thermosetting resin composition of [2], wherein the resin (B) further has a carboxyl group.

[4] A photosensitive thermosetting resin composition comprising (E) a polyimide resin having an imide ring, a phenolic hydroxyl group and a carboxyl group, (C) a photobase generator, and (D) a thermosetting component.

[5] The photosensitive thermosetting resin composition according to any one of [1] to [4], wherein the thermosetting component (D) is a cyclic ether compound.

[6] The photosensitive thermosetting resin composition according to any one of [1] to [5], wherein the resin composition is for a flexible printed wiring board.

[7] A dry film comprising a resin layer comprising the photosensitive thermosetting resin composition according to any one of [1] to [6].

[8] A printed wiring board comprising a cured product formed using the photosensitive thermosetting resin composition according to any one of [1] to [6], or the dry film according to [7].

According to the present invention, a photosensitive thermosetting resin composition that can be developed with alkali, has excellent heat resistance and flexibility, and is easy to manage temperature and time during heat curing after light irradiation, and water containing the photosensitive thermosetting resin composition It becomes possible to provide the dry film which has a paper layer, and the flexible printed wiring board provided with the hardened|cured material of the said photosensitive thermosetting resin composition. The photosensitive thermosetting resin composition of this invention is suitable for the insulating film of a flexible printed wiring board, especially the batch formation process of a bent part (bend|bend part) and a mounting part (non-bend|bend part).

BRIEF DESCRIPTION OF THE DRAWINGS It is a process diagram which shows typically an example of the manufacturing method of the flexible printed wiring board of this invention.

The first photosensitive thermosetting resin composition of the present invention comprises (A) a polyimide resin having an imide ring and a carboxyl group, (B) a resin having a phenolic hydroxyl group, (C) a photobase generator, and (D) a thermosetting component. It is characterized by including. The second photosensitive thermosetting resin composition of the present invention comprises (E) a polyimide resin having an imide ring, a phenolic hydroxyl group and a carboxyl group, (C) a photobase generator, and (D) a thermosetting component. will be.

In either case, by using a base generated from a photobase generator as a catalyst, the polyimide resin having a carboxyl group and a thermosetting component are subjected to an addition reaction by heating after exposure, and the unexposed portion is removed with an alkaline solution. It is common in that it is a resin composition which makes this possible. Moreover, any photosensitive thermosetting resin composition also has a phenolic hydroxyl group in a system.

As will be described later, when a phenolic hydroxyl group is present, compared to the case in which it does not exist, the time until alkali resistance is achieved by addition reaction under the same heating temperature in the heat curing reaction after exposure (at the time of the PEB process below) can be long In addition, it is possible to widen the selection range of the heating temperature during the heat curing reaction (in the PEB process below). From these points, workability and handleability of the resin composition are improved. Generation|occurrence|production of the so-called cloudiness from which an unexposed part becomes alkali tolerance can also be suppressed.

The photosensitive thermosetting resin composition of this invention is suitable for the resin insulating layer of a flexible printed wiring board, for example, a coverlay, and a soldering resist.

When forming the resin insulating layer of a flexible printed wiring board using the photosensitive thermosetting resin composition of this invention, a suitable manufacturing method becomes as follows. That is, on a flexible printed wiring board, a step of forming a resin layer containing the photosensitive thermosetting resin composition of the present invention, a step of irradiating the resin layer with light in a pattern shape, a step of heating the resin layer (Post Exposure Bake; also referred to as PEB) ), and alkali-developing the resin layer to form a resin insulating layer having a pattern. If necessary, after alkali development, light irradiation or heat curing (post-curing) is further performed to completely harden the resin composition, and a highly reliable resin insulating layer is obtained.

As described above, in the photosensitive thermosetting resin composition of the present invention, suitably, a carboxyl group and a thermosetting component are addition-reacted by heat treatment after selective light irradiation, whereby negative pattern formation by alkali development becomes possible.

Since the obtained cured product is excellent in heat resistance and flexibility and can be fine-processed by alkali development, it is not necessary to partially use an alkali-developable photosensitive resin composition with respect to polyimide, and the bent part of a flexible printed wiring board It can be used for either (bending part) and mounting part (non-bending part), and it is suitable for the batch formation process of a bent part (bending part) and a mounting part (non-bending part).

The first photosensitive thermosetting resin composition of the present invention comprises (A) a polyimide resin having an imide ring and a carboxyl group, (B) a resin having a phenolic hydroxyl group, (C) a photobase generator, and (D) a thermosetting component. It is characterized by including. Resin which has phenolic hydroxyl group other than polyimide resin which has an imide ring and a carboxyl group is included. It is preferable that resin which has this phenolic hydroxyl group also has an imide ring so that it may mention later, and it may have a carboxyl group. Hereinafter, each component will be described in detail.

[(A) Polyimide resin having an imide ring and a carboxyl group]

In this invention, (A) polyimide resin which has an imide ring and a carboxyl group is resin which has a carboxyl group and an imide ring.

(A) It is preferable that polyimide resin which is a component has a partial structure represented by following formula (1) as an imide ring. In formula (1), it is preferable that R contains an aromatic ring.

It is more preferable that the partial structure represented by said Formula (1) is a thing represented by following formula (2) or (3).

The position of the carboxyl group is not particularly limited. A carboxyl group may exist as a substituent of the said imide ring or a group bonding with it, and a carboxyl group may be introduce|transduced into a polyimide resin by synthesis|combining using what has a carboxyl group as an amine component or an isocyanate component.

(A) A well-known and usual method can be used for synthesis|combination of the polyimide resin which is a component. For example, resin obtained by making a carboxylic anhydride component, an amine component, and/or an isocyanate component react is mentioned. Imidization may be performed by thermal imidization, chemical imidization may be performed, and these may be used together and it may manufacture.

Examples of the carboxylic acid anhydride component include tetracarboxylic anhydride and tricarboxylic acid anhydride. can be used including In addition, these carboxylic acid anhydride components may be used individually by 1 type, and may be used in combination of 2 or more type.

Examples of the tetracarboxylic anhydride include pyromellitic dianhydride, 3-fluoropyromellitic dianhydride, 3,6-difluoropyromellitic dianhydride, and 3,6-bis(trifluoromethyl). ) pyromellitic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 4,4'- oxydiphthalic 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(tri Fluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',5,5'-tetrakis(trifluoromethyl)-3,3',4, 4'-biphenyltetracarboxylic dianhydride, 2,2',6,6'-tetrakis(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, 5,5′,6,6′-tetrakis(trifluoromethyl)-3,3′,4,4′-biphenyltetracarboxylic dianhydride, and 2,2′,5,5′,6 ,6'-hexakis(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3, 3",4,"-Terphenyltetracarboxylic dianhydride, 3,3'",4,4'"-Quarterphenyltetracarboxylic dianhydride, 3,3"",4,4""-quinqui Phenyltetracarboxylic dianhydride, methylene-4,4'-diphthalic dianhydride, 1,1-ethynylidene-4,4'-diphthalic dianhydride, 2,2-propylidene-4,4'- Diphthalic dianhydride, 1,2-ethylene-4,4'-diphthalic dianhydride, 1,3-trimethylene-4,4'-diphthalic dianhydride, 1,4-tetramethylene-4,4'- Diphthalic dianhydride, 1,5-pentamethylene-4,4'-diphthalic dianhydride, 2 ,2-bis(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride, difluoromethylene-4,4'-diphthalic dianhydride, 1, 1,2,2-tetrafluoro-1,2-ethylene-4,4'-diphthalic dianhydride, 1,1,2,2,3,3-hexafluoro-1,3-trimethylene-4 ,4'-diphthalic dianhydride, 1,1,2,2,3,3,4,4-octafluoro-1,4-tetramethylene-4,4'-diphthalic dianhydride, 1,1, 2,2,3,3,4,4,5,5-decafluoro-1,5-pentamethylene-4,4'-diphthalic dianhydride, thio-4,4'-diphthalic dianhydride, alcohol Ponyl-4,4'-diphthalic dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethylsiloxane dianhydride, 1,3-bis (3,4 -dicarboxyphenyl)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenyl)benzene dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4- Bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,3-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, 1,4-bis[2-( 3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, bis[3-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, bis[4-(3,4-dicarboxyphenoxy) )phenyl]methane dianhydride, 2,2-bis[3-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl ]propane dianhydride, 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-tetramethyldisiloxane dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 3, 4,9,10-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride, 1, 2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cycle Lobutanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexane-1,2,3,4-tetracarboxylic dianhydride, cyclohexane-1,2,4,5-tetracarboxyl Acid dianhydride, 3,3',4,4'-bicyclohexyltetracarboxylic dianhydride, carbonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, methylene -4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,2-ethylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride , 1,1-ethynylidene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 2,2-propylidene-4,4'-bis(cyclohexane-1, 2-dicarboxylic acid) dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-propylidene-4,4'-bis(cyclohexane-1,2-dicarboxyl 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 dianhydride, 5, 5'-difluorooxy-4,4'-diphthalic dianhydride, 6,6'-difluorooxy-4,4'-diphthalic dianhydride, 3,3',5,5',6, 6'-hexafluorooxy-4,4'-diphthalic dianhydride, 3,3'-bis(trifluoromethyl)oxy-4,4'-diphthalic dianhydride, 5,5'-bis(tri Fluoromethyl)oxy-4,4'-diphthalic dianhydride, 6,6'-bis(trifluoromethyl)oxy-4,4'-diphthalic dianhydride, 3,3',5,5'- tetrakis(trifluoromethyl)oxy-4,4'-diphthalic dianhydride, 3,3',6,6'-tetrakis(trifluoromethyl)oxy-4,4'-diphthalic dianhydride; 5,5',6,6'-tetrakis(trifluoromethyl)oxy-4,4'-diphthalic dianhydride, 3,3',5,5',6,6'-hexakis(trifluoro Romethyl)oxy-4,4'-diphthalic dianhydride, 3,3'-difluorosulfonyl-4,4'-diphthalic dianhydride, 5,5'-difluorosulfonyl-4,4 '-diphthalic dianhydride, 6,6'-difluorosulfonyl-4,4'-diphthalic dianhydride, 3,3' ,5,5',6,6'-hexafluorosulfonyl-4,4'-diphthalic dianhydride, 3,3'-bis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride Water, 5,5'-bis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride, 6,6'-bis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride Water, 3,3',5,5'-tetrakis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride, 3,3',6,6'-tetrakis(trifluoromethyl ) sulfonyl-4,4'-diphthalic dianhydride, 5,5',6,6'-tetrakis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride, 3,3', 5,5',6,6'-hexakis(trifluoromethyl)sulfonyl-4,4'-diphthalic dianhydride, 3,3'-difluoro-2,2-perfluoropropylidene- 4,4'-diphthalic dianhydride, 5,5'-difluoro-2,2-perfluoropropylidene-4,4'-diphthalic dianhydride, 6,6'-difluoro-2, 2-perfluoropropylidene-4,4'-diphthalic dianhydride, 3,3',5,5',6,6'-hexafluoro-2,2-perfluoropropylidene-4,4 '-diphthalic dianhydride, 3,3'-bis(trifluoromethyl)-2,2-perfluoropropylidene-4,4'-diphthalic dianhydride, 5,5'-bis(trifluoro methyl)-2,2-perfluoropropylidene-4,4'-diphthalic dianhydride, 6,6'-difluoro-2,2-perfluoropropylidene-4,4'-diphthalic dianhydride Water, 3,3',5,5'-tetrakis(trifluoromethyl)-2,2-perfluoropropylidene-4,4'-diphthalic dianhydride, 3,3',6,6' -tetrakis(trifluoromethyl)-2,2-perfluoropropylidene-4,4'-diphthalic dianhydride, 5,5',6,6'-tetrakis(trifluoromethyl)-2 ,2-Perfluoropropylidene-4,4'-diphthalic dianhydride, 3,3',5,5',6,6'-hexakis(trifluoromethyl)-2,2-perfluoro Propylene-4,4'-diphthalic dianhydride, 9-phenyl-9-(trifluoromethyl)xanthene-2,3,6,7-tetracarboxylic dianhydride, 9,9-bis(tri Fluoromethyl) xanthene-2,3,6,7-tetracarboxylic dianhydride, bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracar carboxylic acid dianhydride, 9,9-bis[4-(3,4-dicarboxy)phenyl]fluorene dianhydride, 9,9-bis[4-(2,3-dicarboxy)phenyl]fluorene dianhydride Water, ethylene glycol bistrimellitate dianhydride, 1,2-(ethylene)bis(trimellitate anhydride), 1,3-(trimethylene)bis(trimellitate anhydride), 1,4-(tetramethylene) Bis(trimellitate anhydride), 1,5-(pentamethylene)bis(trimellitate anhydride), 1,6-(hexamethylene)bis(trimellitate anhydride), 1,7-(heptamethylene)bis( trimellitate anhydride), 1,8-(octamethylene)bis(trimellitate anhydride), 1,9-(nonamethylene)bis(trimellitate anhydride), 1,10-(decamethylene)bis(trimelli tate anhydride), 1,12-(dodecamethylene)bis(trimellitate anhydride), 1,16-(hexadecamethylene)bis(trimellitate anhydride), 1,18-(octadecamethylene)bis(tri melitate anhydride) and the like.

As tricarboxylic acid anhydride, trimellitic acid anhydride, nuclear hydrogenated trimellitic acid anhydride, etc. are mentioned, for example.

As an amine component, although diamines, such as an aliphatic diamine and aromatic diamine, polyhydric amines, such as an aliphatic polyetheramine, can be used, It is not limited to these amines. In addition, these amine components can also be used individually or in combination.

Examples of the diamine include one benzene nucleus such as p-phenylenediamine (PPD), 1,3-diaminobenzene, 2,4-toluenediamine, 2,5-toluenediamine, and 2,6-toluenediamine. diaminodiphenyl ethers such as diamine, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, and 3,4'-diaminodiphenyl ether, 4,4'-diamino Diphenylmethane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl) -4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodi Phenylmethane, bis(4-aminophenyl)sulfide, 4,4'-diaminobenzanilide, 3,3'-dichlorobenzidine, 3,3'-dimethylbenzidine (o-tolidine), 2,2'- Dimethylbenzidine (m-tolidine), 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' -diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 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'-diaminodiphenyl Benzene nucleus 2 such as sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide, and 3,3'-dicarboxy-4,4'-diaminodiphenylmethane Diamine, 1,3-bis(3-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(3-aminophenyl)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'-di(4-phenylphenoxy)benzophenone, 1,3-bis(3- Aminophenylsulfide)benzene, 1,3-bis(4-aminophenylsulfide)benzene, 1,4-bis(4-aminophenylsulfide)benzene, 1,3-bis(3-aminophenylsulfone)benzene , 1,3-bis(4-aminophenylsulfone)benzene, 1,4-bis(4-aminophenylsulfone)benzene, 1,3-bis[2-(4-aminophenyl)isopropyl]benzene, 1, Diamines having three benzene nuclei, such as 4-bis[2-(3-aminophenyl)isopropyl]benzene, 1,4-bis[2-(4-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] Ether, bis[4-(4-aminophenoxy)phenyl]ether, bis[3-(3-aminophenoxy)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) cy)phenyl]sulfone, bis[3-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone , 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)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- Aromatic diamines such as diamines having four benzene nuclei such as hexafluoropropane and 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane , 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1 ,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,2-diaminocyclohexane Aliphatic diamines, such as these, are mentioned, As an aliphatic polyetheramine, ethylene glycol and/or a polyhydric amine of a propylene glycol system, etc. are mentioned. Moreover, you can also use the amine which has a carboxyl group as follows. 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-bis(3-aminophenoxy)benzoic acid; Aminophenoxybenzoic acids such as 3,5-bis(4-aminophenoxy)benzoic acid, 3,3'-diamino-4,4'-dicarboxybiphenyl, 4,4'-diamino-3,3 Carboxylic acid such as '-dicarboxybiphenyl, 4,4'-diamino-2,2'-dicarboxybiphenyl, 4,4'-diamino-2,2',5,5'-tetracarboxybiphenyl Biphenyl 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-amino-3-carboxyphenyl]propane, 2,2-bis[3-amino-4-carboxyphenyl]hexafluoropropane, 4,4 Carboxydiphenyl alkanes such as carboxydiphenylmethane such as '-diamino-2,2',5,5'-tetracarboxydiphenylmethane, 3,3'-diamino-4,4'-dicarboxydi Phenyl ether, 4,4'-diamino-3,3'-dicarboxydiphenyl ether, 4,4'-diamino-2,2'-dicarboxydiphenyl ether, 4,4'-diamino-2 Carboxydiphenyl ether compounds such as 2',5,5'-tetracarboxydiphenyl ether, 3,3'-diamino-4,4'-dicarboxydiphenylsulfone, 4,4'-diamino-3 ,3'-dicarboxydiphenylsulfone, 4,4'-diamino-2,2'-dicarboxydiphenylsulfone, 4,4'-diamino-2,2',5,5'-tetracarboxydi Diphenylsulfone compounds such as phenylsulfone, bis[(carboxyphenyl)phenyl]alkane compounds such as 2,2-bis[4-(4-amino-3-carboxyphenoxy)phenyl]propane, 2,2-bis Bis[(carboxyphenoxy)phenyl]sulfone compounds, such as [4-(4-amino-3-carboxyphenoxy)phenyl]sulfone, etc. are mentioned.

As the isocyanate component, diisocyanates such as aromatic diisocyanate, isomers and multimers thereof, aliphatic diisocyanates, alicyclic diisocyanates and isomers thereof, and other general-purpose diisocyanates can be used, but it is not limited to these isocyanates. . In addition, these isocyanate components can also be used individually or in combination.

As diisocyanate, for example, 4,4'- diphenylmethane diisocyanate, tolylene diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, biphenyl diisocyanate, diphenyl sulfone diisocyanate, diphenyl ether diisocyanate, etc. aliphatic diisocyanates such as aromatic diisocyanate and its isomers, multimers, hexamethylene diisocyanate, isophorone diisocyanate and dicyclohexylmethane diisocyanate, or alicyclic diisocyanates and isomers obtained by hydrogenating the aromatic diisocyanate; or other general-purpose diisocyanates.

(A) The polyimide resin as component may have an amide bond. The amide bond obtained by making isocyanate and carboxylic acid react may be sufficient as this, and it may be based on reaction other than that. In addition, it may have other bonds including addition and condensation.

(A) For the synthesis of the polyimide resin as component, known and usual alkali-soluble polymers, oligomers, and monomers having a carboxyl group and/or an acid anhydride group may be used. For example, these known and usual alkali-soluble resins are used alone. , or a resin obtained by reacting with the amine/isocyanate in combination with the carboxylic acid anhydride component.

(A) In order to respond to an alkali image development process, it is preferable that the acid value is 20-200 mgKOH/g, and, as for the polyimide resin which is component (A), it is preferable that it is 60-150 mgKOH/g more suitably. When this acid value is 20 mgKOH/g or more, solubility with respect to alkali increases, developability becomes favorable, Furthermore, since the degree of crosslinking with the thermosetting component after light irradiation becomes high, sufficient image development contrast can be obtained. Moreover, when this acid value is 200 mgKOH/g or less, so-called thermal clouding in the PEB process after light irradiation mentioned later can be suppressed, and a process margin becomes large.

Moreover, when developability and cured coating-film characteristic are considered, 1,000-100,000 are preferable and, as for the molecular weight of the polyimide resin which is (A) component, 2,000-50,000 are still more preferable.

When this molecular weight is 1,000 or more, sufficient develop resistance and hardening property can be obtained after exposure and PEB. Moreover, when molecular weight is 100,000 or less, alkali solubility increases and developability improves.

[(B) Resin having a phenolic hydroxyl group]

(B) The resin having a phenolic hydroxyl group is not particularly limited as long as it has a phenolic hydroxyl group in the main chain or a side chain, that is, a hydroxyl group bonded to a benzene ring. A phenolic hydroxyl group may also react with a thermosetting component like a carboxyl group.

Preferably, it is a compound which has two or more phenolic hydroxyl groups in 1 molecule.

Examples of the compound having two or more phenolic hydroxyl groups in one molecule include catechol, resorcinol, hydroquinone, dihydroxytoluene, naphthalenediol, t-butylcatechol, t-butylhydroquinone, pyrogallol, phloroglucinol, Bisphenol A, bisphenol F, bisphenol S, biphenol, bixylenol, novolak type phenol resin, novolak type alkylphenol resin, bisphenol A novolak resin, dicyclopentadiene type phenol resin, Xylok type phenol resins, terpene-modified phenol resins, polyvinyl phenols, condensates of phenols and aromatic aldehydes having phenolic hydroxyl groups, and condensates of 1-naphthol or 2-naphthols and aromatic aldehydes, but are limited to these it is not going to be These phenolic hydroxyl group containing compounds can be used individually or in mixture of 2 or more types.

(B) As resin which is a component, it is preferable to have an imide ring. Examples of the imide ring include those similar to those described above. As resin which has an imide ring and a phenolic hydroxyl group, the polyimide resin synthesize|combined using the diamine which has a phenolic hydroxyl group with respect to the above carboxylic acid anhydride is preferable, for example. Examples of the diamine having a phenolic hydroxyl group include diaminophenols such as 2,4-diaminophenol, 3,3'-diamino-4,4'-dihydroxybiphenyl, and 4,4'-dia Mino-3,3'-dihydroxybiphenyl, 4,4'-diamino-2,2'-dihydroxybiphenyl, 4,4'-diamino-2,2',5,5'- Hydroxybiphenyl compounds such as tetrahydroxybiphenyl, 3,3'-diamino-4,4'-dihydroxydiphenylmethane, 4,4'-diamino-3,3'-dihydroxy Cydiphenylmethane, 4,4'-diamino-2,2'-dihydroxydiphenylmethane, 2,2-bis[3-amino-4-hydroxyphenyl]propane, 2,2-bis[4- Amino-3-hydroxyphenyl]propane, 2,2-bis[3-amino-4-hydroxyphenyl]hexafluoropropane, 4,4'-diamino-2,2',5,5'-tetra Hydroxydiphenyl alkanes such as hydroxydiphenylmethane such as hydroxydiphenylmethane, 3,3'-diamino-4,4'-dihydroxydiphenyl ether, 4,4'-diamino-3 ,3'-dihydroxydiphenyl ether, 4,4'-diamino-2,2'-dihydroxydiphenyl ether, 4,4'-diamino-2,2',5,5'-tetra Hydroxydiphenyl ether compounds such as hydroxydiphenyl ether, 3,3'-diamino-4,4'-dihydroxydiphenylsulfone, 4,4'-diamino-3,3'-dihydroxy Cydiphenylsulfone, 4,4'-diamino-2,2'-dihydroxydiphenylsulfone, 4,4'-diamino-2,2',5,5'-tetrahydroxydiphenylsulfone, etc. Bis[(hydroxyphenyl)phenyl]alkane compounds such as diphenylsulfone compound, 2,2-bis[4-(4-amino-3-hydroxyphenoxy)phenyl]propane, 4,4'-bis( Bis(hydroxyphenoxy)biphenyl compounds such as 4-amino-3-hydroxyphenoxy)biphenyl, 2,2-bis[4-(4-amino-3-hydroxyphenoxy)phenyl]sulfone Bis[(hydroxyphenoxy)phenyl]sulfone compounds such as 4,4'-diamino-3,3'-dihydroxydiphenylmethane, 4,4'-diamino-2,2'-dihydroxy Carboxydiphenyl alkanes such as hydroxydiphenylmethane, 4,4'-diamino-2,2'-dihydroxydiphenylmethane, 4,4'-bis(4-amino-3-hydroxyphenoxy) Bis(hydroxyphenoxy)biphenyl compounds such as biphenyl, 1,3-bis(3-amino-4-hi and bis(hydroxyphenoxy)benzene compounds such as hydroxyphenoxy)benzene and 1,3-bis(4-amino-3-hydroxyphenoxy)benzene.

The molecular weight of the resin having a phenolic hydroxyl group is preferably 1,000 to 100,000, more preferably 2,000 to 50,000, in consideration of developability, develop resistance, and cured coating film properties after exposure and PEB.

[(C) Photobase Generator]

(C) The photobase generator can function as a catalyst for addition reaction between a polyimide resin having a carboxyl group and a thermosetting component by changing the molecular structure or cleaving the molecule by irradiation with light such as ultraviolet or visible light. A compound that produces one or more basic substances in As a basic substance, a secondary amine and a tertiary amine are mentioned, for example.

As the photobase generator, for example, α-aminoacetophenone compound, oxime ester compound, acyloxyimino group, N-formylated aromatic amino group, N-acylated aromatic amino group, nitrobenzylcarbamate group, alkoxybenzyl The compound etc. which have substituents, such as a carbamate group, are mentioned. Especially, an oxime ester compound and (alpha)-aminoacetophenone compound are preferable. As the α-aminoacetophenone compound, it is particularly preferable to have two or more nitrogen atoms.

As other photobase generators, WPBG-018 (trade name: 9-anthrylmethylN,N'-diethylcarbamate), WPBG-027 (trade name: (E)-1-[3-(2-hyde) Roxyphenyl)-2-propenoyl]piperidine), WPBG-082 (trade name: guanidinium 2-(3-benzoylphenyl)propionate), WPBG-140 (trade name: 1-(anthraquinone-2) -yl) ethyl imidazole carboxylate), etc. can also be used.

The α-aminoacetophenone compound has a benzoin ether bond in the molecule, and when irradiated with light, cleavage occurs in the molecule to form a basic substance (amine) that exhibits a curing catalytic action. Specific examples of the α-aminoacetophenone compound include (4-morpholinobenzoyl)-1-benzyl-1-dimethylaminopropane (Irgacure 369, trade name, manufactured by BASF Japan) and 4-(methylthio). Benzoyl)-1-methyl-1-morpholinoethane (Irgacure 907, trade name, manufactured by BASF Japan), 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4- A commercially available compound such as (4-morpholinyl)phenyl]-1-butanone (Irgacure 379, trade name, manufactured by BASF Japan) or a solution thereof can be used.

As an oxime ester compound, if it is a compound which produces|generates a basic substance by light irradiation, any can be used. As a commercial item, as such an oxime ester compound, CGI-325 by BASF Japan, Irgacure OXE01, Irgacure OXE02, N-1919 by Adeka Corporation, NCI-831, etc. are mentioned. Moreover, the compound of Unexamined-Japanese-Patent No. 4344400 which has two oxime ester groups in a molecule|numerator can also be used suitably.

In addition, Japanese Patent Laid-Open No. 2004-359639, Japanese Patent Laid-Open No. 2005-097141, Japanese Patent Laid-Open No. 2005-220097, Japanese Patent Laid-Open No. 2006-160634, and Japanese Patent Laid-Open No. 2008-094770 The carbazole oxime ester compound of Unexamined-Japanese-Patent No. 2008-509967, Unexamined-Japanese-Patent No. 2009-040762, and Unexamined-Japanese-Patent No. 2011-80036, etc. are mentioned.

These photobase generators may be used individually by 1 type, and may be used in combination of 2 or more type. The compounding quantity of the photobase generator in the photosensitive thermosetting resin composition becomes like this. Preferably it is 0.1-40 mass parts with respect to 100 mass parts of thermosetting components, More preferably, it is 0.1-30 mass parts. When it is 0.1 mass part or more, the contrast of developability of a light irradiated part/unirradiated part can be obtained favorably. Moreover, when it is 40 mass parts or less, hardened|cured material property improves.

[(D) thermosetting component]

(D) A thermosetting component has a functional group in which addition reaction with a carboxyl group or phenolic hydroxyl group is possible by heat|fever. As a thermosetting component, the compound which has a cyclic (thio) ether group is preferable, for example, and an epoxy resin, a polyfunctional oxetane compound, etc. are mentioned.

The said epoxy resin is resin which has an epoxy group, and any well-known thing can be used. The bifunctional epoxy resin which has two epoxy groups in a molecule|numerator, the polyfunctional epoxy resin which has many epoxy groups in a molecule|numerator, etc. are mentioned. Moreover, the hydrogenated bifunctional epoxy compound may be sufficient.

Examples of the epoxy compound include bisphenol A epoxy resin, brominated epoxy resin, novolak epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, glycidylamine epoxy resin, hydantoin epoxy resin, alicyclic Formula epoxy resins, trihydroxyphenylmethane type epoxy resins, bixylenol type or biphenol type epoxy resins, or mixtures thereof; Bisphenol S type epoxy resin, bisphenol A novolak type epoxy resin, tetraphenylolethane type epoxy resin, heterocyclic epoxy resin, diglycidyl phthalate resin, tetraglycidyl xylenoyl ethane resin, naphthalene group-containing epoxy resin, dicy An epoxy resin having a chloropentadiene skeleton, a glycidyl methacrylate copolymerized epoxy resin, a copolymerized epoxy resin of cyclohexyl maleimide and glycidyl methacrylate, and a CTBN-modified epoxy resin may be mentioned.

As other liquid bifunctional epoxy resins, vinylcyclohexene diepoxide, (3',4'-epoxycyclohexylmethyl)-3,4-epoxycyclohexanecarboxylate, (3',4'-epoxy- and alicyclic epoxy resins such as 6'-methylcyclohexylmethyl)-3,4-epoxy-6-methylcyclohexanecarboxylate. These epoxy resins may be used individually by 1 type, and may use 2 or more types together.

Further, (D) as a thermosetting component, a known and usual compound such as a maleimide compound, a block isocyanate compound, an amino resin, a benzoxazine resin, a carbodiimide resin, a cyclocarbonate compound, and an episulfide resin may be blended. may be

(D) As a compounding quantity of a thermosetting component, it is preferable that an equivalent ratio (a carboxyl group: thermally reactive groups, such as an epoxy group) with the polyimide resin which is (A) component is 1:0.1 - 1:10. By setting it as the range of such a compounding ratio, developability becomes favorable and a fine pattern can be formed easily. The equivalent ratio is more preferably 1:0.2 to 1:5.

The second photosensitive thermosetting resin composition of the present invention comprises (E) a polyimide resin having an imide ring, a phenolic hydroxyl group and a carboxyl group, (C) a photobase generator, and (D) a thermosetting component. . That is, in this invention, a carboxyl group and phenolic hydroxyl group may exist on the same resin.

[(E) Polyimide resin having an imide ring, a phenolic hydroxyl group and a carboxyl group]

(E) Component is a polyimide resin which has an imide ring, a phenolic hydroxyl group, and a carboxyl group. Specifically, the polyimide resin which is the said (A) component introduce|transduced the phenolic hydroxyl group is mentioned. For example, when synthesize|combining polyimide resin, (E) component can be obtained by using the amine component and isocyanate component which have a phenolic hydroxyl group other than a carboxyl group as a raw material.

(E) The molecular weight of the polyimide resin, which is the component, preferably has a mass average molecular weight of 1,000 to 100,000, more preferably 2,000 to 50,000, in consideration of developability after exposure and PEB, develop resistance, and cured coating film properties.

(polymer resin)

A commonly known polymer resin can be mix|blended with the photosensitive thermosetting resin composition of this invention for the purpose of the improvement of the flexibility of the hardened|cured material obtained and dry to touch property. Examples of the polymer resin include cellulose-based, polyester-based, phenoxy resin-based polymers, polyvinylacetal-based, polyvinylbutyral-based, polyamide-based, polyamideimide-based binder polymers, block copolymers, and elastomers. The said polymer resin may be used individually by 1 type, and may use 2 or more types together.

(inorganic filler)

An inorganic filler can be mix|blended with the photosensitive thermosetting resin composition of this invention. An inorganic filler is used in order to suppress cure shrinkage of the hardened|cured material of the photosensitive thermosetting resin composition, and to improve characteristics, such as adhesiveness and hardness. Examples of the inorganic filler include barium sulfate, amorphous silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, silicon nitride, aluminum nitride, boron nitride, Neuburg diatomaceous earth, and the like. can The said inorganic filler may be used individually by 1 type, and may use 2 or more types together.

(coloring agent)

A coloring agent can be further mix|blended with the photosensitive thermosetting resin composition of this invention. As a coloring agent, commonly known coloring agents, such as red, blue, green, yellow, white, and black, can be used, Any of a pigment, dye, and a pigment|dye may be sufficient.

(organic solvent)

An organic solvent can be used for the photosensitive thermosetting resin composition of this invention for preparation of a resin composition, or for viscosity adjustment for apply|coating to a base material or a carrier film.

Examples of such organic solvents include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like. These organic solvents may be used individually by 1 type, and may be used as a mixture of 2 or more types.

(Other optional ingredients)

Components, such as a photopolymerizable monomer, a mercapto compound, an adhesion promoter, antioxidant, and a ultraviolet absorber, can be further mix|blended with the photosensitive thermosetting resin composition of this invention as needed. For these, a well-known thing can be used in the field|area of an electronic material. In addition, in the photosensitive thermosetting resin composition, well-known and usual thickeners such as finely divided silica, hydrotalcite, organic bentonite, and montmorillonite; Conventional additives can be blended.

In addition, the compounding amount of the photopolymerizable monomer is preferably 15 parts by mass or less, more preferably 10 parts by mass or less, and 0 parts by mass (not included) with respect to 100 parts by mass of the polyimide resin as component (A). desirable.

[Dry Film]

The dry film of this invention has a resin layer containing the photosensitive thermosetting resin composition of this invention, It is characterized by the above-mentioned.

In the case of dry film formation, for example, the photosensitive thermosetting resin composition of the present invention is diluted with an organic solvent, adjusted to an appropriate viscosity, and applied to a uniform thickness on a carrier film by a known method such as a comma coater. After that, it is usually dried at a temperature of 50 to 130° C. for 1 to 30 minutes to form a resin layer on the carrier film.

A plastic film is used as the carrier film. Although there is no restriction|limiting in particular about the thickness of a carrier film, Generally, it selects suitably in the range of 10-150 micrometers. After forming a resin layer on a carrier film, you may further laminate|stack the cover film which can peel on the surface of a resin layer.

[Flexible printed wiring board and manufacturing method thereof]

The flexible printed wiring board of this invention has a hardened|cured material containing the resin layer of a photosensitive thermosetting resin composition or a dry film, It is characterized by the above-mentioned.

The manufacturing method of the flexible printed wiring board of this invention includes the process of forming the resin layer containing the photosensitive thermosetting resin composition on a flexible printed wiring board, the process of irradiating light to the resin layer in pattern shape, the process of heating the resin layer, and and alkali-developing the resin layer to form at least one of a coverlay and a solder resist.

[resin layer forming process]

At this process, at least 1 layer of resin layers containing a photosensitive thermosetting resin composition are formed on a flexible printed wiring board.

A coating method and a lamination method are mentioned as a formation method of a resin layer.

In the case of the coating method, the photosensitive thermosetting resin composition is apply|coated on a flexible printed wiring board by methods, such as screen printing, and a resin layer is formed by drying.

In the case of the lamination method, first, the photosensitive thermosetting resin composition is diluted with the organic solvent, it adjusts to an appropriate viscosity, it apply|coats and dries on a carrier film, and the dry film which has a resin layer is produced. Next, after bonding so that a resin layer may contact with a flexible printed wiring board with a laminator etc., a carrier film is peeled.

Moreover, another layer can be interposed between a resin layer and a flexible printed wiring board. It is preferable that another layer contains an alkali developing type photosensitive resin composition. A well-known composition can be used as an alkali developing type photosensitive resin composition, For example, the well-known composition for coverlays or for soldering resists can be used. Thus, by setting it as the laminated structure containing other layers, the hardened|cured material further excellent in impact resistance and flexibility can be obtained.

[Light irradiation process]

At this process, the photobase generator contained in a resin layer is activated by light irradiation in a negative pattern shape, and a light irradiation part is hardened. At this process, a photobase generator is destabilized by the base which generate|occur|produced in the light irradiation part, and it can fully harden even to the deep part of a resin layer by the base multiplying chemically.

As the light irradiator, a direct drawing apparatus, a light irradiator equipped with a metal halide lamp, etc. can be used. The mask for light irradiation on the pattern is a negative type mask.

As an active energy ray used for light irradiation, it is preferable to use the laser beam or scattered light whose maximum wavelength is in the range of 350-450 nm. By making a maximum wavelength into this range, a photobase generator can be activated efficiently. Any of a gas laser and a solid-state laser may be sufficient as long as the laser beam of this range is used. In addition, although the light irradiation amount changes with film thickness etc., it can be generally 100-1500 mJ/cm<2>.

[Heating process]

At this process, a light irradiation part is hardened by heating a resin layer after light irradiation. According to this process, it can harden to a deep part with the base which generate|occur|produced in the light irradiation process. Heating temperature is 80-140 degreeC, for example. The heating time is, for example, 10 to 100 minutes.

Since curing of the photosensitive thermosetting resin composition in the present invention is, for example, a ring-opening reaction of an epoxy resin by a thermal reaction, deformation and curing shrinkage can be suppressed compared to the case where curing proceeds in a photoradical reaction. .

[Development process]

In a developing process, an unirradiated part is removed by alkali development, and the insulating film on a negative type pattern shape, especially a coverlay, and a soldering resist are formed.

As a developing method, it can depend on well-known methods, such as dipping. Moreover, as a developing solution, aqueous alkali solutions, such as potassium hydroxide, amines, tetramethylammonium hydroxide aqueous solution (TMAH), or these mixtures can be used.

In addition, after the development process, the insulating film may be further irradiated with light. Moreover, you can also heat at 150 degreeC or more, for example.

Next, an example of the method of manufacturing the flexible printed wiring board of this invention from the photosensitive thermosetting resin composition of this invention is demonstrated based on the process diagram of FIG. In addition, although the case where the resin layer has a laminated structure is shown in FIG. 1, it may be a case where only one layer is included.

In the lamination process of FIG. 1, the laminated structure containing the resin layer 3 and the resin layer 4 is formed in the flexible printed wiring base material 1 in which the copper circuit 2 was formed.

The resin layer 3 contains the photosensitive resin composition of the alkali developing type containing carboxyl group-containing resin etc.

The resin layer 4 is formed on the resin layer 3, and a polyimide resin having an imide ring and a carboxyl group, a resin having a phenolic hydroxyl group, a photobase generator and a thermosetting component, or an imide ring, a phenolic hydroxyl group, and The photosensitive thermosetting resin composition of this invention containing the polyimide resin which has a carboxyl group, a photobase generator, and a thermosetting component is included.

In the light irradiation step of FIG. 1 , the mask 5 is disposed on the resin layer 4 and light is irradiated in a negative pattern shape to activate the photobase generator contained in the photosensitive thermosetting resin composition, and the light irradiation unit It is a curing process. The heating process of FIG. 1 is a process (PEB process) of hardening a light irradiation part by heating a resin layer after a light irradiation process. The developing process of FIG. 1 is a process of forming a negative pattern layer by removing an unirradiated part by developing with alkaline aqueous solution.

In addition, the 2nd light irradiation process of FIG. 1 is a process for activating the remaining photobase generator as needed to generate a base, and a thermosetting process is a process for fully thermosetting a pattern layer, if necessary. am.

Example

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

(Examples 1 to 7, Comparative Examples 1 and 2)

<The synthesis example of the polyimide resin solution which has an imide ring and a carboxyl group>

12.5 g of 3,5-diaminobenzoic acid, 2,2'-bis[4-(4-aminophenoxy)phenyl] 8.2 g of propane, 30 g of NMP, 30 g of γ-butyrolactone, 27.9 g of 4,4'-oxydiphthalic anhydride, and 3.8 g of trimellitic anhydride were added, and under nitrogen atmosphere, room temperature, 100 rpm for 4 hours stirred. Next, 20 g of toluene was added, and the mixture was stirred for 4 hours while distilling off toluene and water at a silicone bath temperature of 180°C and 150 rpm to obtain a polyimide resin solution (PI-1) having an imide ring and a carboxyl group.

The acid value of the obtained resin (solid content) was 85 mgKOH, and the weight average molecular weight (Mw) was 10000.

<The synthesis example of the polyimide resin solution which has an imide ring and a phenolic hydroxyl group>

22.4 g of 3,3'-diamino-4,4'-dihydroxydiphenylsulfone, 2,2'-bis[ 8.2 g of 4-(4-aminophenoxy)phenyl]propane, 30g of NMP, 30g of γ-butyrolactone, 27.9g of 4,4'-oxydiphthalic anhydride, 3.0g of phthalic anhydride, nitrogen Under atmosphere, it stirred at room temperature and 100 rpm for 4 hours. Next, 20 g of toluene was added, and the mixture was stirred for 4 hours while distilling off toluene and water at a silicone bath temperature of 180°C and 150 rpm to obtain an alkali-soluble resin solution (PI-2) having an imide ring and a phenolic hydroxyl group.

The obtained resin (solid content) had a hydroxyl equivalent of 384 and Mw was 10000.

<The synthesis example of the polyimide resin solution which has an imide ring, a phenolic hydroxyl group, and a carboxyl group>

22.4 g of 3,3'-diamino-4,4'-dihydroxydiphenylsulfone, 2,2'-bis[ 8.2 g of 4-(4-aminophenoxy)phenyl]propane, 30g of NMP, 30g of γ-butyrolactone, 27.9g of 4,4'-oxydiphthalic anhydride, and 3.8g of trimellitic anhydride were added , under a nitrogen atmosphere, at room temperature and 100 rpm, the mixture was stirred for 4 hours. Then, 20 g of toluene was added, and the mixture was stirred for 4 hours while distilling off toluene and water at a silicone bath temperature of 180° C. and 150 rpm to obtain an alkali-soluble resin solution (PI-3) having an imide ring, a phenolic hydroxyl group and a carboxyl group.

The acid value of the obtained resin (solid content) was 18 mgKOH, Mw was 10000, and the hydroxyl equivalent was 390.

<Preparation of photosensitive thermosetting resin composition>

Each of the materials of each base material was blended according to the formulation shown in Table 1 below, premixed with a stirrer, and then kneaded with a triaxial roll mill to prepare a photosensitive thermosetting resin composition. Values in the table are parts by mass unless otherwise specified.

<Formation process of resin layer>

The flexible printed wiring base material in which the circuit is formed with 18 micrometers of copper thickness was prepared, and it pre-processed using Mecsa CZ-8100. Then, the photosensitive thermosetting resin composition of Examples 1-7 and Comparative Examples 1 and 2 was coated on the flexible printed wiring board which performed the said pretreatment so that it might become a film thickness of 10 micrometers after drying by the liquid coating method. Thereafter, the resin layer was formed by drying at 80° C. for 30 minutes in a hot air circulation drying furnace. Then, it light-irradiated in the form of a negative pattern with an exposure amount of 500 mJ/cm<2> with ORC company HMW680GW (metal halide lamp, scattered light).

<Evaluation of time management width of PEB process>

The substrate having the resin layer after exposure was heat-treated at 90°C for 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, or 60 minutes, respectively. Then, the base material was immersed in 30 degreeC 1 mass % sodium carbonate aqueous solution, and image development was performed for 3 minutes, developability was evaluated, and the width (minute) of developable heating time was evaluated.

<Evaluation of developability by temperature of PEB process>

The board|substrate which has the said resin layer after exposure was heat-processed for 80 degreeC 60 minutes, 90 degreeC 30 minutes, and 100 degreeC 15 minutes. Then, the base material was immersed in 30 degreeC 1 mass % sodium carbonate aqueous solution, and image development was performed for 3 minutes, and developability was evaluated.

○ in the table: can be developed and the state of the coating film is good

※ 1: Pattern cannot be formed because the exposed part is dissolved in the developer

※ 2: Pattern cannot be formed because the unexposed part does not dissolve in the developer.

The evaluation results are shown in Table 1 below.

※ The compounding quantity in the table shows the numerical value in solid content (parts by mass).

*1: phenol novolac resin, hydroxyl equivalent 106, manufactured by Meiwa Chemicals Co., Ltd.

*2: Bisphenol A type epoxy resin, manufactured by Mitsubishi Chemical Corporation

*3: Oxime-based photopolymerization initiator, manufactured by BASF

As is clear from the evaluation results shown in Table 1, the photosensitive thermosetting resin compositions of Examples 1 to 7 had good developability even after exposure to heat treatment at any temperature of 80°C, 90°C, or 100°C. Moreover, from evaluation of the PEB time management width at 90 degreeC, compared with the comparative example, it has confirmed that the heating time after exposure can be taken long. From the above, it turns out that the photosensitive thermosetting resin composition which concerns on this invention is remarkably excellent with respect to the temperature control property of a PEB process, and time management width compared with the resin composition of Comparative Examples 1 and 2.

1: Flexible printed wiring board
2: Copper circuit
3: resin layer
4: resin layer
5: Mask

Claims (8)

(A) a polyimide resin having an imide ring and a carboxyl group;
(B) a resin having an imide ring, a phenolic hydroxyl group and a carboxyl group;
(C) a photobase generator, and
(D) thermosetting component
A photosensitive thermosetting resin composition comprising a. delete delete The photosensitive thermosetting resin composition according to claim 1, wherein the thermosetting component (D) is a cyclic ether compound. The photosensitive thermosetting resin composition according to claim 1, wherein the resin composition is for a flexible printed wiring board. It has a resin layer containing the photosensitive thermosetting resin composition of Claim 1, The dry film characterized by the above-mentioned. A printed wiring board comprising a cured product formed using a dry film having a resin layer comprising the photosensitive thermosetting resin composition according to claim 1 or the photosensitive thermosetting resin composition according to claim 1 . delete

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