JP5494341B2 - Thermosetting resin composition, cured product thereof and interlayer adhesive film for printed wiring board - Google Patents

Description

  The present invention is excellent in dimensional stability of a cured product, excellent in low-temperature meltability at the time of semi-curing (B-stage formation), and has good flexibility and is difficult to curl when formed into a film at the time of B-stage formation. The present invention relates to a thermosetting polyimide resin composition in which a film is obtained and the viscosity change with time is small, a cured product of the composition, and an interlayer adhesive film for a printed wiring board obtained using the composition.

  In recent years, there has been an increasing demand for thinner, lighter and higher mounting density semiconductor components, and the wiring density of circuit boards is expected to increase further in the future. As means for improving the wiring density, for example, a three-dimensional circuit is formed by stacking wiring boards. In the future, the number of laminated layers is expected to reach 10 layers or more. As the number of laminated layers increases, the generation of circuit strain stress due to the difference in thermal expansion between the insulating layer and the copper foil has been regarded as a problem. Has been demanded.

  However, on the other hand, a low linear expansion resin generally has poor melt processability, and there is a problem that a curable composition using this resin is not suitable for a circuit board lamination process. For this reason, the appearance of a resin that achieves both low thermal expansion and melt processability is particularly strongly desired in the industry.

  Polyamideimide resin having a glass transition temperature of 330 ° C. preferably as a resin composition from which a cured product having excellent mechanical strength, adhesion strength to adherend, film formability, heat resistance, and pressure resistance is obtained in addition to melt processability (Toyobo Co., Ltd. Viromax HR16NN), diphenylethane bismaleimide (KAI Kasei Co., Ltd. BMI-70), and an allylphenol resin (Showa Kasei Kogyo Co., Ltd. MEH-8000H) are disclosed. (For example, refer to Patent Document 1). However, since the resin composition uses a thermoplastic high molecular weight polyamideimide resin, the low-temperature melting property is poor, and the compatibility with the maleimide compound is poor, so that phase separation occurs when the coating film is cured. There is a problem that a uniform coating film is difficult to obtain and there is a residual solvent in the B stage because a high boiling point solvent such as NMP is used. As an effect of this, there is a problem that the B-stage coating film swells and peels when it is hot-pressed on the substrate. Further, since the allylphenol resin is used in the resin composition, the cured coating film is brittle and inferior in flexibility.

  Further, a resin composition containing a siloxane-modified polyimide, 2,2-bis (4-hydroxy-3-allylphenyl) propane, and diphenylethane bismaleimide as a resin composition for obtaining a cured product having excellent adhesion to an adherend A composition is disclosed. However, the resin composition also has a linear expansion coefficient increased due to the siloxane skeleton introduced in the imide resin, resulting in deterioration of dimensional stability and adhesion to various substrates such as metals, plastics, and inorganic materials. There's a problem.

JP 2004-168894 A (page 10) JP 2000-223805 (page 18)

  The problems of the present invention are that the present invention is excellent in dimensional stability of a cured product, excellent in low-temperature meltability during semi-curing (B-stage), and has good flexibility when formed into a B-stage film. Provides a thermosetting polyimide resin composition having a low viscosity change over time, a cured product of the composition, and an interlayer adhesive film for a printed wiring board obtained using the composition There is to do.

  As a result of intensive studies, the present inventors have found that a resin composition containing a thermosetting polyimide resin and a maleimide compound has a biphenyl skeleton directly linked to a five-membered cyclic imide skeleton as a thermosetting polyimide resin, and has a weight average molecular weight ( Using a polyimide resin having a Mw) of 3,000 to 150,000, an aromatic ring as a maleimide compound, and a polymaleimide compound having a molecular weight of 200 to 1,000, the cured product has a low coefficient of linear expansion. A cured product with excellent dimensional stability can be obtained, a cured product obtained by making a B-stage has excellent low-temperature meltability, a film with excellent flexibility when formed into a film, and a curl-resistant film can be obtained, viscosity As a result, the present invention was completed.

  That is, the present invention includes a thermosetting polyimide resin (A) having a biphenyl skeleton directly connected to a nitrogen atom in a five-membered cyclic imide skeleton and having a weight average molecular weight (Mw) of 3,000 to 150,000, A thermosetting polyimide resin composition comprising an aromatic ring and a polymaleimide compound (B) having a molecular weight of 200 to 1,000 is provided.

  The present invention also provides a cured product obtained by curing the thermosetting polyimide resin composition.

  Furthermore, the present invention provides an interlayer adhesive film for a printed wiring board comprising a layer formed of the thermosetting polyimide resin composition on a carrier film.

  Although the thermosetting polyimide resin composition of the present invention is excellent in low-temperature meltability after being B-staged, the cured product has a low coefficient of linear expansion and excellent dimensional stability. Moreover, the film obtained by making into B-stage is excellent in a flexibility, and is hard to curl. Moreover, the viscosity is less likely to change with time and is easy to handle. It can be used in various fields by utilizing these performances. Specifically, engine peripheral parts, sliding parts, HDD sliding parts, voice coils, electromagnetic coils, coating agents for various films, insulation coatings for electric wires, heat resistance such as cooking devices, insulation Applications requiring coating properties: Fiber-reinforced composite materials such as carbon fiber prepregs, printed wiring boards, semiconductor insulating materials, coverlays, surface protection layers such as solder resists, build-up materials, prepreg resins, flexible displays Insulating materials, organic TFT insulating layers, buffer coatings, low-k semiconductor coatings, polymer waveguides, semiconductor sealants, adhesives such as underfill, etc .; solar cells, lithium batteries, capacitors, electricity Insulating layers such as double layer capacitors, electrode binders, various energy industrial materials such as separators; -Endless belts such as transfer belts and fixing belts for printers and copiers or coating agents, conductive films, binders for heat dissipation films, alignment films for color filters, overcoat films, etc. Especially for insulating layers such as multilayer printed wiring boards It can be suitably used for solder resist. Also, by using the interlayer adhesive film for printed wiring boards of the present invention, an insulating layer having a low coefficient of linear expansion of the cured product can be obtained while being melted at a low temperature at the time of crimping with a copper foil. It is suitably used as an adhesive film for forming an insulating layer.

  The thermosetting polyimide resin (A) has a weight average molecular weight (Mw) of 3,000 to 150,000. If the weight average molecular weight (Mw) is less than 3,000, the flexibility of the B-staged cured product deteriorates, which is not preferable. When the weight average molecular weight (Mw) is larger than 150,000, the melt viscosity increases, it becomes impossible to melt, and the low-temperature meltability of the B-staged cured product is unfavorable. The weight average molecular weight (Mw) is preferably 5,000 to 50,000.

In the present invention, the weight average molecular weight (Mw) was measured using a gel permeation chromatograph (GPC) under the following conditions.
Measuring device: Tosoh Corporation HLC-8320GPC, UV8320
Column: Super AWM-H × 2 manufactured by Tosoh Corporation Detector: RI (differential refractometer) and UV (254 nm)
Data processing: Tosoh Corporation EcoSEC-WorkStation
Measurement conditions: Column temperature 40 ° C
Solvent DMF
Flow rate 0.35 ml / min Standard: Calibration curve prepared with polystyrene standard sample Sample: 0.2% by weight DMF solution in terms of resin solid content filtered through a microfilter (injection volume: 10 μl)

  The thermosetting polyimide resin (A) has a biphenyl skeleton that is directly linked to the imide skeleton. The inventor believes that a cured product obtained by curing the thermosetting polyimide resin composition of the present invention having such a structure is excellent in dimensional stability.

  The biphenyl skeleton has good compatibility with the aromatic ring of the maleimide compound (B) described later. Therefore, the thermosetting imide resin composition of the present invention provides a cured product having excellent dimensional stability. Furthermore, the inventor believes that the low-molecular-weight maleimide compound (B) enters the rigid and hard-to-move thermosetting polyimide resin (A) and is excellent in the low-temperature meltability of the B-staged cured product.

  When the content of the biphenyl skeleton in the thermosetting polyimide resin (A) is 20 to 45% by mass, a cured product having excellent dimensional stability is obtained, and the low-temperature meltability of the B-staged cured product is also excellent. To 25 to 40% by mass, more preferably 25 to 35% by mass.

  The content of the biphenyl structure is such that the molecular weight is 152 when the biphenyl structure is bonded to the polyimide resin main chain and the molecular weight is 150 when the biphenyl structure is bonded at 4 positions. It can be calculated from the ratio of the biphenyl structure to the weight.

  Further, the logarithmic viscosity of the thermosetting polyimide resin (A) is 0.1 to 0.9 dl / g, and a cured product with sufficient strength can be obtained, and low-temperature melting when B-stage is achieved. This is preferable because a thermosetting imide resin composition having excellent properties can be obtained. The logarithmic viscosity of the thermosetting polyimide resin (A) is preferably 0.2 to 0.8 dl / g, and more preferably 0.3 to 0.7 dl / g.

In the present invention, the logarithmic viscosity of the thermosetting polyimide resin (A) was determined under the following conditions.
A polyimide resin was dissolved in N-methyl-2-pyrrolidone so that the resin concentration was 0.5 g / dl to obtain a resin solution. The solution viscosity of the resin solution and the solvent viscosity (viscosity of N-methyl-2-pyrrolidone) were measured at 30 ° C. with an Ubbelohde type viscosity tube, and the obtained measured values were obtained by applying the following formulas. .

Logarithmic viscosity (dl / g) = [ln (V1 / V2)] / V3
In the above formula, V1 represents the solution viscosity measured with an Ubbelohde type viscosity tube, and V2 represents the solvent viscosity measured with an Ubbelohde type viscosity tube. Here, V1 and V2 were determined from the time required for the resin solution and the solvent (N-methyl-2-pyrrolidone) to pass through the capillary of the viscosity tube. V3 is the polymer concentration (g / dl).

  As a thermosetting polyimide resin (A), the polyimide resin etc. which have the following structures can be illustrated, for example.

(In the formula, R ₁ represents a hydrogen atom, an alkyl group which may be substituted with a halogen atom such as a fluorine atom, etc., and (a1) and (a2) may both exist, The structure is always present in the resin.)

  Examples of the polyimide resin having the structures (a1) and (a2) include a polyimide resin having the following structure.

  The thermosetting polyimide resin (A) can be easily obtained by, for example, a method of reacting a polyisocyanate having a biphenyl skeleton with an acid anhydride. As such a method, for example, a polyisocyanate compound (a1) having a biphenyl skeleton and / or an acid anhydride (a2) having a biphenyl skeleton and, if necessary, a polyisocyanate compound (a3) other than (a1), A method of reacting an acid anhydride (a4) other than (a2) may be mentioned.

  Here, instead of the polyisocyanate compound (a1) and the polyisocyanate compound (a3), a polyamine compound having a main structure in each compound is used to react with the acid anhydride (a2) or acid anhydride (a4). It is also possible to obtain a similar imide resin.

  Examples of the polyisocyanate compound (a1) having a biphenyl skeleton include 4,4′-diisocyanate-3,3′-dimethyl-1,1′-biphenyl and 4,4′-diisocyanate-3,3′-diethyl. -1,1'-biphenyl, 4,4'-diisocyanate-2,2'-dimethyl-1,1'-biphenyl, 4,4'-diisocyanate-2,2'-diethyl-1,1'-biphenyl, Examples include 4,4′-diisocyanate-3,3′-ditrifluoromethyl-1,1′-biphenyl, 4,4′-diisocyanate-2,2′-ditrifluoromethyl-1,1′-biphenyl, and the like.

  Examples of the acid anhydride (a2) having the biphenyl skeleton include biphenyl-3,3 ′, 4,4′-tetracarboxylic acid, biphenyl-2,3,3 ′, 4′-tetracarboxylic acid, and these Monoanhydrides, dianhydrides, and the like. These can be used alone or as a mixture of two or more.

  Examples of the polyisocyanate compound (a3) other than (a1) include aromatic polyisocyanates and aliphatic polyisocyanates other than (a1).

  Examples of the aromatic polyisocyanate other than (a1) include p-phenylene diisocyanate, m-phenylene diisocyanate, p-xylene diisocyanate, m-xylene diisocyanate, 2,4-tolylene diisocyanate, and 2,6-tolylene diisocyanate. 4,4'-diphenylmethane diisocyanate, 3,3'-dimethyldiphenyl-4,4'-diisocyanate, 3,3'-diethyldiphenyl-4,4'-diisocyanate, m-xylene diisocyanate, p-xylene diisocyanate, , 3-bis (α, α-dimethylisocyanatomethyl) benzene, tetramethylxylylene diisocyanate, diphenylene ether-4,4′-diisocyanate and naphthalene diisocyanate.

  Examples of the aliphatic polyisocyanate compound include hexamethylene diisocyanate, lysine diisocyanate, trimethylhexamethylenemethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, hydrogenated xylene diisocyanate, and norbornene diisocyanate.

  As the polyisocyanate compound, an isocyanate prepolymer obtained by reacting the polyisocyanate compound and various polyol components in advance with an excess of isocyanate groups may be used, or modification such as burette formation, isocyanurate conversion, carbodiimidization, and uretdione conversion may be performed. It is also possible to use it.

  The thermosetting polyimide resin (A) is preferably a thermosetting polyimide resin obtained by reacting a polyisocyanate having a biphenyl skeleton with an acid anhydride. In particular, the polyisocyanate having the biphenyl skeleton is a tolidine diisocyanate. Alternatively, thermosetting polyimide resin (A) synthesized from polyisocyanate derived from tolidine diisocyanate is preferable.

  The thermosetting polyimide resin (A) may have a branched structure in order to improve solvent solubility and compatibility with other resins. As the branching method, as the polyisocyanate compound, for example, a tri- or higher functional polyisocyanate compound having an isocyanurate ring that is an isocyanurate body such as the diisocyanate compound, a burette body, an adduct body, an allohanate body of the diisocyanate, or Polymethylene polyphenyl polyisocyanate (crude MDI) or the like may be used.

  Examples of the acid anhydride (a4) other than (a2) include aromatic tricarboxylic acid anhydrides, alicyclic tricarboxylic acid anhydrides other than (a2), and tetracarboxylic acid anhydrides other than (a2). . Examples of aromatic tricarboxylic acid anhydrides other than (a2) include trimellitic anhydride and naphthalene-1,2,4-tricarboxylic acid anhydride.

  Examples of the alicyclic tricarboxylic acid anhydride include cyclohexane-1,3,4-tricarboxylic acid anhydride-3,4-anhydride, cyclohexane-1,3,5-tricarboxylic acid anhydride-3,5-anhydride, And cyclohexane-1,2,3-tricarboxylic acid anhydride-2,3-anhydride.

  Examples of tetracarboxylic acid anhydrides other than (a2) include pyromellitic dianhydride, benzophenone-3,3 ', 4,4'-tetracarboxylic dianhydride, diphenyl ether-3,3', 4. , 4'-tetracarboxylic dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, naphthalene-2,3,6,7-tetracarboxylic dianhydride, naphthalene-1,2 , 4,5-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 4, 8-Dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8- Tetracarboxylic dianhydride, , 7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene- 1,3,9,10-tetracarboxylic dianhydride, berylene-3,4,9,10-tetracarboxylic dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3 , 4-dicarboxyphenyl) methane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,3-bis (3,4-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) sulfone Anhydride Bis (3,4-carboxyphenyl) ether dianhydride,

Ethylene glycol bisanhydro trimellitate, propylene glycol bis anhydro trimellitate, butanediol bis anhydro trimellitate, hexamethylene glycol bis anhydro trimellitate, polyethylene glycol bis anhydro trimellitate, polypropylene lenglycol bis Anhydro trimellitate, other alkylene glycol bisan hydroxy trimellitate, etc. are mentioned.

  The thermosetting polyimide (A) is further preferable because a polyimide resin having a benzophenone structure further exhibits heat resistance and low linear expansion. A polyimide resin having a benzophenone structure can be obtained, for example, by using benzophenone tetracarboxylic acid anhydride as an essential component in the production method.

  The content of the benzophenone structure is preferably from 1 to 30% by mass based on the mass of the polyimide resin, since a cured product having excellent heat resistance is obtained, and more preferably from 5 to 20% by mass is excellent in synthetic stability.

  The content of the benzophenone structure can be calculated from the ratio of the benzophenone structure to the total weight of the polyimide resin, with the molecular weight of the benzophenone structure having 4 bonding points to the polyimide resin main chain being 178.

  Further, the thermosetting polyimide (A) is preferable because a polyimide resin having a tolylene structure is more likely to exhibit melt adhesion and low linear expansion. The polyimide resin having a tolylene structure can be obtained, for example, by using toluene diisocyanate as an essential component in the production method.

  The content of the tolylene structure can be calculated from the proportion of the tolylene structure in the total weight of the polyimide resin, with the molecular weight of the tolylene structure of the polyimide resin main chain being 150.

  The content of the tolylene structure in the polyimide resin is preferably 1 to 20% by mass because it is excellent in synthesis stability, and 2 to 14% by weight is more preferable because it is excellent in low linear expansion and synthesis stability.

  In the said manufacturing method, a polyisocyanate compound and the compound which has an acid anhydride group react. The ratio (ma) / (mb) of the number of moles of isocyanate groups in the polyisocyanate compound (ma) and the total number of moles of non-hydroxyl groups and carboxyl groups in the compound having an acid anhydride group (mb) is expressed as the molecular weight. A ratio of 0.7 to 1.2 is preferable, and a ratio of 0.8 to 1.2 is more preferable because a polyimide resin from which a large polyimide resin can be easily obtained and a cured product having excellent mechanical properties is obtained. Moreover, since it is easy to obtain the polyimide resin which is excellent in storage stability, the (ma) / (mb) is more preferably in the range of 0.9 to 1.1. In addition, when using together carboxylic anhydrides, such as trimellitic anhydride, said (mb) is the total number of moles of a hydroxyl-free group and a carboxyl group in all the carboxylic anhydrides.

  In the case of producing in a one-step reaction in the production method, for example, a reaction vessel is charged with a polyisocyanate compound and a compound having an acid anhydride group, and the reaction is allowed to proceed while decarboxylation by heating while stirring. .

  The reaction temperature can be in the range of 50 ° C. to 250 ° C., and is preferably performed at a temperature of 70 ° C. to 180 ° C. in terms of reaction rate and prevention of side reactions.

  The reaction is preferable because the stability of the resulting polyimide resin is improved when the reaction is performed until almost all isocyanate groups have reacted. Moreover, you may make it react by adding an alcohol and a phenol compound with respect to the isocyanate group which remains a little.

  When producing the thermosetting polyimide resin (A), it is preferable to use an organic solvent because a uniform reaction can proceed. Here, the organic solvent may be present after being present in the system in advance or may be introduced in the middle. In order to maintain an appropriate reaction rate, the proportion of the organic solvent in the system is preferably 98% by mass or less of the reaction system, more preferably 10 to 90% by mass, and more preferably 40 to 90% by mass. % Is more preferable. As such an organic solvent, since a compound containing an isocyanate group is used as a raw material component, an aprotic polar organic solvent having no active proton such as a hydroxyl group or an amino group is preferable.

  As the aprotic polar organic solvent, for example, polar organic solvents such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, sulfolane, and γ-butyrolactone can be used. In addition to the above solvents, ether solvents, ester solvents, ketone solvents, petroleum solvents and the like may be used as long as they are soluble. Various solvents may be mixed and used.

  In particular, use of dimethylacetamide is preferred from the viewpoint of reducing the amount of residual solvent when the coating film is dried and cured, and the solubility of the polyimide resin.

  Examples of ether solvents that can be used in the method for producing a polyimide resin used in the present invention include ethylene glycol dialkyl ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and ethylene glycol dibutyl ether; diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Polyethylene glycol dialkyl ethers such as diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, and triethylene glycol dibutyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, etc. Polyethylene glycol monoalkyl ether acetates such as diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether acetate, triethylene glycol monobutyl ether acetate Alkyl ether acetates;

Propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dibutyl ether; dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol dibutyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, tripropylene glycol Polypropylene glycol dialkyl ethers such as propylene glycol dibutyl ether; propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate; Polypropylene glycol monoalkyl ether acetate such as triglycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monobutyl ether acetate, tripropylene glycol monomethyl ether acetate, tripropylene glycol monoethyl ether acetate, tripropylene glycol monobutyl ether acetate Dialkyl ethers of copolymerized polyether glycols such as low molecular weight ethylene-propylene copolymers; monoacetate monoalkyl ethers of copolymerized polyether glycols; alkyl esters of copolymerized polyether glycols; Examples include ether glycol monoalkyl esters and monoalkyl ethers. It is.

  Examples of the ester solvent include ethyl acetate and butyl acetate. Examples of the ketone solvent include acetone, methyl ethyl ketone, and cyclohexanone. In addition, as the petroleum solvent, it is also possible to use toluene, xylene, other high-boiling aromatic solvents, and aliphatic and alicyclic solvents such as hexane and cyclohexane.

  Whether the thermosetting polyimide resin (A) is dissolved in an organic solvent is determined by adding the polyimide resin concentration of the present invention to 10% by mass in an organic solvent and allowing to stand at 25 ° C. for 7 days. This can be done by visually observing the appearance.

  The thermosetting polyimide resin (A) may be a polyimide resin having a linear structure or a polyimide resin having a branched structure. Further, the copolymer component may have a polyester-modified polyesterimide or urethane-modified polyurethaneimide structure.

  The polyimide resin (A) in the present invention needs to be a thermosetting type, and examples of the resin terminal structure include structures such as carboxylic acid, carboxylic acid anhydride, isocyanate group, and amine group. Can be mentioned. As the terminal structure, the structure of the carboxylic acid or its anhydride is preferable because the stability of the polyimide resin itself of the present invention and the stability after blending with an organic solvent or another resin are good. When the terminal structure is a structure of carboxylic acid or its anhydride, the acid value is 5 to 200 in terms of solid content acid value, the thermoplasticity is not strong, the crosslinkability is good, and it is difficult to separate when the composition is cured. It is preferable from the viewpoint that the cured product is not easily brittle and the storage stability of the composition is good, more preferably 10 to 100, still more preferably 10 to 50.

  The thermosetting polyimide resin (A) is preferably a polyimide resin that does not have an alkylene structure that causes a reduction in dimensional stability.

  The polymaleimide compound (B) used in the present invention has an aromatic ring. As described above, by having an aromatic ring, the compatibility with the biphenyl skeleton of the thermosetting polyimide resin (A) is improved, the melting temperature and the viscosity of the composition are lowered, and when they are further cured by reaction, mutual Due to the effects of stacking and the like, the thermosetting imide resin composition of the present invention can provide a cured product having excellent dimensional stability, and it is considered that the B-staged cured product has excellent low-temperature meltability.

  The polymaleimide compound (B) has a molecular weight of 200 to 1,000. By using the polymaleimide compound (B) having a molecular weight within this range, the melt viscosity of the resin composition of the present invention is reduced, the stability in solution is improved, the curling property of the B-stage film is prevented, the flexibility is ensured, etc. The effect is obtained. The molecular weight is preferably 250 to 600, more preferably 260 to 400.

  As the polymaleimide compound (B), for example, a compound represented by the following formula can be preferably used.

  (A2) represents a divalent organic group having an aromatic ring.

  Examples of the compound represented by the formula (a2) include the following compounds.

[Wherein, R ₃ represents a single bond or methylene, R ₄ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, respectively, and n is an integer of 0 to 4. ]

  Examples of the compound represented by the formula (b2-1) include the compounds shown below.

  Among the polymaleimide compounds (B), phenylenebisbisphenol is obtained because a thermosetting polyimide resin composition having a low melt viscosity of a B-staged cured product and excellent dimensional stability of a completely cured product is obtained. Maleimide or methylphenylene bismaleimide is preferred.

  As the usage-amount of a polymaleimide compound (B), the melt viscosity of the hardened | cured material in which 5-200 mass parts B-staged with respect to 100 mass parts of polyimide resins (A) falls, and the hardened | cured material fully cured is used. It is preferable because a thermosetting polyimide resin composition having excellent dimensional stability is obtained, and 10 to 100 parts by mass is more preferable because the mechanical properties of the obtained cured product become tough.

  The thermosetting polyimide resin composition of the present invention is preferable because it contains a cured product having good toughness and good adhesion to a substrate and an interlayer adhesive film for printed wiring boards by containing (C) an epoxy resin. . The epoxy resin (C) preferably has two or more epoxy groups in the molecule. Examples of such epoxy resins include bisphenol type epoxy resins such as bisphenol A type epoxy resins, bisphenol S type epoxy resins, and bisphenol F type epoxy resins; biphenyl type epoxy resins; naphthalene type epoxy resins; phenol novolac epoxy resins and cresol novolac types. Epoxy resins, novolak type epoxy resins such as bisphenol type novolacs; epoxidized products of various dicyclopentadiene modified phenolic resins obtained by reacting dicyclopentadiene with various phenols; epoxy resins having a fluorene skeleton; 10- (2,5 -Dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide and the like, and a phosphorus-containing epoxy resin; neopentyl glycol di Aliphatic epoxy resins such as ricidyl ether and 1,6-hexanediol diglycidyl ether; 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, bis- (3,4-epoxycyclohexyl) adipate, etc. And alicyclic epoxy resins; and heterocycle-containing epoxy resins such as triglycidyl isocyanurate. Among them, at least one epoxy resin selected from the group consisting of bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, and naphthalene type epoxy resin is obtained. It is preferable because the composition is excellent in meltability at low temperature while being expanded.

  By using at least one epoxy resin selected from the group consisting of bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, and naphthalene type epoxy resin, the cured product has low linear expansion. And, the excellent meltability at low temperature is that the polyimide resin (A) has a biphenyl structure and the epoxy resin has a bisphenol A structure, a bisphenol F structure, a biphenyl structure, and a naphthalene structure, The inventors speculate that the epoxy resin prevents aggregation of the polyimide resin at the time of melting, and at the same time, the epoxy resin interacts closely after curing to form a dense cured state.

  Moreover, as a molecular weight of such an epoxy resin (C), the range of 300-1,000 is preferable at the surface of coexistence of a meltability and adhesiveness, and also the fall of a linear expansion coefficient, and the range of 300-500 is more preferable.

  The content of the epoxy resin (C) is 5 to 200% by mass with respect to 100 parts by mass of the polyimide resin (A), and the cured product has low linear expansion, and is a thermosetting type excellent in meltability at low temperatures. The resin composition is preferably obtained, more preferably 10 to 150% by mass, and still more preferably 10 to 100% by mass.

  Moreover, since the viscosity of an epoxy resin (C) becomes a composition excellent in low temperature meltability, the epoxy resin whose viscosity in 150 degreeC is 12 Pa * s or less is preferable, and the epoxy resin of 10 Pa * s or less is more preferable.

  Boron compounds such as boric acid and / or boric acid esters can be used in combination with the thermosetting polyimide resin composition of the present invention. Examples of such compounds include boric acid; trialkyl such as trimethyl borate, triethyl borate, tributyl borate, tri-n-octyl borate, tri (triethylene glycol methyl ether) borate ester, tricyclohexyl borate, and trimenthyl borate. Linear aliphatic borate esters typified by borate esters; aromatic borate esters such as tri-o-cresyl borate, tri-m-cresyl borate, tri-p-cresyl borate, triphenyl borate, tri Boric acid esters containing two or more boron atoms such as (1,3-butanediol) biborate, tri (2-methyl-2,4-pentanediol) biborate, trioctylene glycol diborate, etc. and containing a cyclic structure ; Polyvinyl alcohol borate ester Xylene glycol anhydrous boric acid to.

  Furthermore, phosphorus compounds such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide can also be added to the thermosetting polyimide resin composition of the present invention.

  When a compound other than the epoxy resin (C) is added to the thermosetting polyimide resin composition of the present invention, a thermosetting resin composition having excellent storage stability is obtained, and a cured coating film having excellent dimensional stability is obtained. Since it is obtained, boric acid and a linear aliphatic borate ester are preferable. Among the linear aliphatic borate esters, trialkyl borate esters having 4 to 20 carbon atoms are preferable, and tributyl borate (tributyl borate) is particularly preferable.

  Other thermosetting resin components can be further added to the thermosetting polyimide resin composition of the present invention. Specifically, a phenol compound, an isocyanate compound, a silicate, an alkoxysilane compound, a melamine resin, etc. are mentioned, for example.

  Preferred examples of the phenol compound include, for example, bisphenol compounds having two or more phenolic hydroxyl groups in one molecule such as bisphenol A, bisphenol F, and bisphenol S; hydroquinone, 4,4′-biphenol, 3,3′- 1 phenolic hydroxyl group such as dimethyl-4,4′biphenol, 3,3 ′, 5,5′-tetramethylbiphenol, 2,4-naphthalenediol, 2,5-naphthalenediol, 2,6-naphthalenediol A compound having two or more in the molecule, a phenol compound containing a phosphorus atom such as 10- (2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide; a phenol novolac resin; Cresol novolac resin, t-butylphenol Borac resin, dicyclopentagencresol novolak resin, dicyclopentagen phenol novolak resin, xylylene-modified phenol novolak resin, naphthol novolak resin, trisphenol novolak resin, tetrakisphenol novolak resin, bisphenol A novolak resin, poly-p-vinylphenol Examples thereof include novolak type phenol resins such as resins, aminotriazine novolak type phenol resins, and phenol aralkyl resins. These phenol resins can be used alone or in combination of two or more. Among them, cured products from which 10- (2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide and aminotriazine novolac-type phenol resins are obtained have high heat resistance, flame resistance, and low linear expansion. However, it is preferable because the composition has excellent meltability at low temperatures.

  Examples of the isocyanate compound include aromatic isocyanate compounds, aliphatic isocyanate compounds, and alicyclic isocyanate compounds. Preferably, a polyisocyanate compound having two or more isocyanate groups in one molecule is preferable. A blocked isocyanate compound can also be used.

  Examples of the alkylalkoxysilane include alkyltrialkoxysilane and dialkyldialkoxysilane.

  Examples of the alkyltrialkoxysilane include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, ethyltributoxysilane, Examples thereof include phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, and phenyltributoxysilane.

  Examples of the dialkyl dialkoxysilane include dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldipropoxysilane, diethyldibutoxysilane, and diphenyldimethoxy. Silane, diphenyldiethoxysilane, diphenyldipropoxysilane, diphenyldibutoxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, methylethyldipropoxysilane, methylethyldibutoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane , Methylphenyldipropoxysilane, methylphenyldibutoxysilane, trimethylmethoxysilane, trimethyl ether Kishishiran, triethyl silane, triethyl silane, triphenyl methoxy silane, triphenyl ethoxy silane, and the like.

  Moreover, the condensate of alkyl alkoxysilane can also be used, for example, the condensate of the above-mentioned alkyl trialkoxysilane, the condensate of dialkyl dialkoxysilane, etc. are mentioned.

  As the melamine resin, for example, an alkoxylated melamine resin obtained by reacting a part or all of a methylol product obtained by reaction of a triazine ring-containing amino compound such as melamine or benzoguanamine with formaldehyde is used with an alcohol compound. be able to. As the alcohol compound used here, a lower alcohol having about 1 to 4 carbon atoms can be used. Specifically, a methoxymethylolated melamine resin, a butylated methylolated melamine resin, or the like can be used. The molecular structure may be completely alkoxylated, a methylol group may remain, or an imino group may remain.

  This alkoxylated melamine resin, in the thermosetting resin composition of the present invention, has the effect of preventing precipitation with time when boric acid and / or boric acid esters are added in addition to the improvement of heat resistance and physical properties as a crosslinking component. Yes, it improves the stability as a thermosetting resin composition.

  As the resin structure of the alkoxylated melamine resin, the methoxymethylolated melamine resin is preferable because of compatibility with the polyimide resin and good curability at the time of curing, and more preferably, a methoxymethylol having a methoxylation rate of 80% or more. A melamine resin is more preferable.

  The resin structure may be a polynuclear body by self-condensation. The degree of polymerization at this time is preferably about 1 to 5 in terms of compatibility and stability, and more preferably about 1.2 to 3.

  As the number average molecular weight of the alkoxylated melamine resin, those having a molecular weight of 100 to 10,000 can be used. Preferably, 300 to 2000 is preferable in terms of compatibility with the polyimide resin and curability at the time of curing, and more preferably 400 to 1000.

  As the alkoxylated melamine resin, even if melamine, benzoguanamine, formalin and alcohol are simultaneously charged and reacted, melamine or benzoguanamine and formalin are reacted in advance to obtain a methylolated melamine compound and then alkoxylated with the alcohol compound. May be.

  Specific examples of commercially available alkoxylated melamine resins include, for example, product Cymel 300, 301, 303, and 305 manufactured by Nippon Cytec Industries, as methoxymethylolated melamine resins. Examples of the methylol group-containing methoxymethylolated melamine resin include product Cymel 370 and 771 manufactured by Nippon Cytec Industries. Examples of the imino group-containing methoxylated melamine resin include commercial Cymel 325, 327, 701, 703, and 712 manufactured by Mitsui Cytec Co., Ltd. Examples of the methoxylated butoxylated melamine resin include product Cymel 232, 235, 236, 238, 266, 267, 285 manufactured by Nippon Cytec Industries. Examples of the butoxylated melamine resin include product Uban 20SE60 manufactured by Nippon Cytec Industries.

  Furthermore, the thermosetting polyimide resin composition of the present invention includes polyester resins, phenoxy resins, PPS resins, PPE resins, polyarylene resins and other binder resins, phenol resins, melamine resins, alkoxysilane curing agents, polybasic acid anhydrides, cyanates. Curing agents such as compounds or reactive compounds, melamine, dicyandiamide, guanamine and derivatives thereof, imidazoles, amines, phenols having one hydroxyl group, organic phosphines, phosphonium salts, quaternary ammonium salts, photocationic catalysts, etc. Anti-foaming material, leveling agent, slip agent, wetting improver, anti-settling agent, flame retardant, antioxidant, UV absorber, etc. can be added as a curing catalyst, curing accelerator, filler, and other additives. is there.

  The thermosetting polyimide resin composition of the present invention is preferably a composition in which the cured product has a linear expansion coefficient of 50 ppm / ° C. or less when the composition is cured.

  In addition, various fillers, organic pigments, inorganic pigments, extender pigments, rust inhibitors and the like can be added to the thermosetting polyimide resin composition of the present invention as necessary. These may be used alone or in combination of two or more.

  Examples of the filler include barium sulfate, barium titanate, silicon oxide powder, finely divided silicon oxide, silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, mica, and alumina. Is mentioned.

  As the filler, those having various particle sizes can be used, and can be added to such an extent that the physical properties of the present resin and its composition are not impaired. Such an appropriate amount is in the range of about 5 to 80% by mass, and preferably used after being uniformly dispersed. As a dispersion method, it is possible to carry out dispersion by a known roll, bead mill, high-speed dispersion or the like, and the surface of the particles may be modified in advance with a dispersion treatment agent.

  Examples of the organic pigment include azo pigments; copper phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green, and quinacridone pigments.

  Examples of the inorganic pigment include chromates such as chrome lead, zinc chromate and molybdate orange; ferrocyanides such as bitumen, titanium oxide, zinc white, bengara, iron oxide; metal oxides such as chromium carbide green, Cadmium yellow, cadmium red; metal sulfides such as mercury sulfide; selenides; sulfates such as lead sulfate; silicates such as ultramarine; carbonates, cobalt biored; phosphates such as manganese purple; aluminum powder, zinc dust Metal powders such as brass powder, magnesium powder, iron powder, copper powder and nickel powder; carbon black and the like.

  In addition, any of other coloring, rust prevention, and extender pigments can be used. These may be used alone or in combination of two or more.

  The cured product of the present invention is obtained by curing the thermosetting polyimide resin composition of the present invention. Specifically, for example, the thermosetting polyimide resin composition of the present invention includes a cured product that is cured by heating at 100 to 300 ° C. after coating on a substrate.

  The substrate used in the method for forming the coating film can be used without any particular limitation. Examples of the substrate include plastic, metal, wood, glass, inorganic material, and composite materials thereof. There is no restriction | limiting in particular as a shape of a base material, A sheet | seat, a film-like thing, a chip | tip shape, a solid shape, etc. can be illustrated.

  The interlayer adhesive film for printed wiring boards of the present invention is characterized by having a layer formed of a thermosetting polyimide resin composition on a carrier film. Such an adhesive film can illustrate the form of the film (adhesive film) which consists of a layer (A layer) and a support body film (B layer) of the thermosetting polyimide resin composition of this invention, for example.

  The adhesive film is prepared according to various methods, for example, preparing a resin varnish obtained by dissolving the thermosetting polyimide resin composition of the present invention in an organic solvent, applying the resin varnish to a support film, and heating or blowing hot air, etc. Thus, the organic solvent can be dried to form a resin composition layer.

  The support film (B layer) serves as a support when the adhesive film is produced, and is finally peeled off or removed in the production of the printed board. Examples of the support film include polyolefins such as polyethylene and polyvinyl chloride, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”), polyesters such as polyethylene naphthalate, polycarbonate, and release paper and copper foil. The metal foil etc. can be mentioned. In addition, when using copper foil as a support body film, it can remove by etching with etching liquid, such as ferric chloride and cupric chloride. The support film may be subjected to a release treatment in addition to a mat treatment and a corona treatment, but it is more preferable that the release treatment is performed in consideration of releasability. Although the thickness of a support film is not specifically limited, Usually, it is 10-150 micrometers, Preferably it is used in 25-50 micrometers.

  Organic solvents for preparing the varnish include, for example, ketones such as acetone, methyl ethyl ketone, cyclohexanone, acetates such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, carbitol acetate, cellosolve, butyl Examples thereof include carbitols such as carbitol, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and gamma butyrolactone. Two or more organic solvents may be used in combination.

  The drying conditions are not particularly limited, but the drying is performed so that the content of the organic solvent in the resin composition is usually 5% by mass or less, preferably 3% by mass or less. The specific drying conditions vary depending on the curability of the resin composition and the amount of the organic solvent in the varnish. For example, in a varnish containing 30 to 60% by mass of an organic solvent, it is usually 3 to 13 minutes at 80 to 120 ° C. It can be dried to some extent. Those skilled in the art can appropriately set suitable drying conditions by simple experiments.

  The thickness of the resin composition layer (A layer) can usually be in the range of 5 to 500 μm. The preferred range of the thickness of the A layer varies depending on the use of the adhesive film, and when used for manufacturing a multilayer flexible circuit board by the build-up method, the thickness of the conductor layer forming the circuit is usually 5 to 70 μm. The thickness of the A layer corresponding to the layer is preferably in the range of 10 to 100 μm.

  The A layer may be protected with a protective film. By protecting with a protective film, it is possible to prevent dust and the like from being attached to the surface of the resin composition layer and scratches. The protective film is peeled off during lamination. As the protective film, the same material as the support film can be used. Although the thickness of a protective film is not specifically limited, Preferably it is the range of 1-40 micrometers.

  The adhesive film obtained using the thermosetting polyimide resin composition of the present invention can be suitably used particularly for the production of a multilayer printed board. Below, the method to manufacture a printed circuit board is demonstrated. The adhesive film obtained by using the thermosetting polyimide resin composition of the present invention can be suitably laminated on a printed board with a vacuum laminator. The printed circuit board used here is mainly a conductor layer patterned on one or both sides of a substrate such as a fiber reinforced prepreg such as an epoxy substrate or a glass epoxy substrate, a polyester substrate, a polyimide substrate, a polyamideimide substrate, or a liquid crystal polymer substrate. (Circuit) As a matter of course, a multilayer printed circuit board in which a circuit and an insulating layer are alternately formed and a circuit is formed on one side or both sides can be used for further multilayering. In addition, from the viewpoint of adhesion of the insulating layer to the circuit board, the surface of the circuit should have been previously roughened with a surface treatment agent such as hydrogen peroxide / sulfuric acid or MEC Etch Bond (MEC Co., Ltd.). preferable.

  Commercially available vacuum laminators include, for example, a vacuum applicator manufactured by Nichigo Morton, a vacuum pressurizing laminator manufactured by Meiki Seisakusho, a roll dry coater manufactured by Hitachi Techno Engineering Co., Ltd., Hitachi AIC ( A vacuum laminator manufactured by Co., Ltd. can be mentioned.

In the lamination, when the adhesive film has a protective film, the protective film is removed, and then the adhesive film is pressure-bonded to the circuit board while being pressurized and heated. The laminating conditions include pre-heating the adhesive film and the circuit board as required, laminating at a pressure of preferably 70 to 140 ° C., a pressure of pressure of preferably 1 to 11 kgf / cm ² and laminating under a reduced pressure of an air pressure of 20 mmHg or less. preferable. The laminating method may be a batch method or a continuous method using a roll.

  After laminating the adhesive film on the circuit board, it is cooled to around room temperature and the support film is peeled off. Next, the thermosetting polyimide resin composition laminated on the circuit board is cured by heating. The conditions for heat curing are usually selected in the range of 150 to 220 ° C. for 20 to 180 minutes, more preferably in the range of 160 to 200 ° C. for 30 to 120 minutes. When the support film has a release treatment or a release layer such as silicon, the support film can be peeled after the thermosetting polyimide resin composition is heat-cured or after heat-curing and punching.

  After the insulating layer, which is a cured product of the thermosetting polyimide resin composition, is formed, holes are drilled in the circuit board by drilling, laser, plasma, or a combination thereof as necessary to form via holes and through holes. It may be formed. In particular, drilling with a laser such as a carbon dioxide laser or a YAG laser is generally used.

  Next, surface treatment of the insulating layer (cured product of thermosetting polyimide resin composition) is performed. The surface treatment can employ a method used in a desmear process, and can be performed in a form that also serves as a desmear process. As a chemical used in the desmear process, an oxidizing agent is generally used. Examples of the oxidizing agent include permanganate (potassium permanganate, sodium permanganate, etc.), dichromate, ozone, hydrogen peroxide / sulfuric acid, nitric acid, and the like. Preferably, an alkaline permanganate solution (for example, potassium permanganate, sodium hydroxide aqueous solution of sodium permanganate), which is an oxidizer widely used for roughening the insulating layer in the production of multilayer printed wiring boards by the build-up method. It is preferable to carry out the treatment using A treatment with a swelling agent can also be performed before the treatment with the oxidizing agent. Further, after the treatment with an oxidizing agent, neutralization treatment with a reducing agent is usually performed.

  After the surface treatment, a conductor layer is formed by plating on the surface of the insulating layer. The conductor layer can be formed by a method combining electroless plating and electrolytic plating. Alternatively, a plating resist having a pattern opposite to that of the conductor layer can be formed, and the conductor layer can be formed only by electroless plating. After the conductor layer is formed, the peel strength of the conductor layer can be further improved and stabilized by annealing at 150 to 200 ° C. for 20 to 90 minutes.

  As a method for forming a circuit by patterning the conductor layer, for example, a subtractive method or a semi-additive method known to those skilled in the art can be used. In the case of the subtractive method, the thickness of the electroless copper plating layer is 0.1 to 3 μm, preferably 0.3 to 2 μm. An electroplating layer (panel plating layer) is formed thereon with a thickness of 3 to 35 μm, preferably 5 to 20 μm, an etching resist is formed, and etching is performed with an etching solution such as ferric chloride or cupric chloride. After forming a conductor pattern by this, a circuit board can be obtained by peeling an etching resist. In the case of the semi-additive method, after forming the electroless copper plating layer with an electroless copper plating layer thickness of 0.1 to 3 μm, preferably 0.3 to 2 μm, a pattern resist is formed, and then the electrolytic copper A circuit board can be obtained by peeling after plating.

  A film in which the support film is replaced with a heat-resistant resin layer (heat-resistant resin film), that is, a film composed of the thermosetting polyimide resin composition layer (A layer) and the heat-resistant resin layer (C layer) of the present invention is flexible. It can be used as a base film for circuit boards. A film composed of the thermosetting polyimide resin composition layer (A layer), heat resistant resin layer (C layer) and copper foil (D layer) of the present invention can be used as a base film of a flexible circuit board. In this case, the base film has a layer structure in the order of A layer, C layer, and D layer. In the base film as described above, the heat-resistant resin layer is not peeled off and constitutes a part of the flexible circuit board.

  A film in which an insulating layer (A ′ layer) made of a cured product of the thermosetting polyimide resin composition of the present invention is formed on a heat-resistant resin layer (C layer) can be used as a base film for a single-sided flexible circuit board. Moreover, it consists of a film having a layer structure in the order of A ′ layer, C layer and A ′ layer, and A ′ layer, C layer and copper foil (D layer). Similarly, a film having a layer structure can be used as a base film for a double-sided flexible circuit board.

  Examples of the heat-resistant resin used for the heat-resistant resin layer include a polyimide resin, an aramid resin, a polyamideimide resin, and a liquid crystal polymer. In particular, a polyimide resin and a polyamideimide resin are preferable. Moreover, on the characteristic used for a flexible circuit board, the breaking strength is 100 MPa or more, the breaking elongation is 5% or more, the thermal expansion coefficient between 20 and 150 ° C. is 40 ppm or less, and the glass transition temperature is 200 ° C. or more or the decomposition temperature is 300 ° C. It is preferable to use the above heat resistant resin.

  As the heat-resistant resin satisfying such characteristics, a heat-resistant resin that is commercially available in the form of a film can be suitably used. For example, a polyimide film “Upilex-S” manufactured by Ube Industries, Ltd., Toray DuPont Co., Ltd. ) Polyimide film "Kapton", Kaneka Chemical Co., Ltd. polyimide film "Apical", Teijin Advanced Films Ltd. "Aramika", Kuraray Co., Ltd. liquid crystal polymer film "Bexstar", Sumitomo Bakelite Co., Ltd. A polyether ether ketone film “Sumilite FS-1100C” and the like are known.

  The thickness of the heat-resistant resin layer is usually 2 to 150 μm, preferably 10 to 50 μm. As the heat-resistant resin layer (C layer), a surface-treated layer may be used. Examples of the surface treatment include dry treatment such as mat treatment, corona discharge treatment and plasma treatment, chemical treatment such as solvent treatment, acid treatment and alkali treatment, sand blast treatment and mechanical polishing treatment. In particular, from the viewpoint of adhesion to the A layer, it is preferable that plasma treatment is performed.

  A base film for a single-sided flexible circuit board comprising an insulating layer (A ′) and a heat-resistant resin layer (C) can be produced as follows. First, similarly to the adhesive film described above, a resin varnish prepared by dissolving the thermosetting polyimide resin composition of the present invention in an organic solvent is prepared, this resin varnish is applied on a heat-resistant resin film, and heating or hot air blowing is performed. To dry the organic solvent to form a thermosetting polyimide resin composition layer. Conditions such as the organic solvent and drying conditions are the same as those for the adhesive film. The thickness of the resin composition layer is preferably in the range of 5 to 15 μm.

  Next, the thermosetting polyimide resin composition layer is dried by heating to form an insulating layer of the thermosetting polyimide resin composition. The conditions for heat curing are usually selected in the range of 150 to 220 ° C. for 20 to 180 minutes, more preferably in the range of 160 to 200 ° C. for 30 to 120 minutes.

  The production of a base film of a double-sided flexible circuit board film consisting of three layers of an insulating layer (A ′ layer), a heat-resistant resin layer (C) layer and a copper foil (D layer) is made of a heat-resistant resin layer (C layer) and a copper foil. A resin composition may be formed on a copper-clad laminated film made of (D layer) and manufactured in the same manner as described above. Examples of the copper clad laminated film include a cast method two-layer CCL (Copper-clad laminate), a sputtering method two-layer CCL, a laminate method two-layer CCL, and a three-layer CCL. The thickness of the copper foil is preferably 12 μm or 18 μm.

  Commercially available two-layer CCL includes Espanex SC (manufactured by Nippon Steel Chemical Co., Ltd.), Neoprex I <CM>, Neoprex I <LM> (Mitsui Chemicals), S'PERFLEX (Sumitomo Metal Mining Co., Ltd.) Nikaflex F-50VC1 (manufactured by Nikkan Kogyo Co., Ltd.) and the like are mentioned as the commercially available three-layer CCL.

  The production of a base film for a double-sided flexible circuit board film comprising three layers of an insulating layer (A ′ layer), a heat-resistant resin layer (C layer) and an insulating layer (A ′ layer) can be carried out as follows. First, in the same manner as the adhesive film described above, a resin varnish prepared by dissolving the thermosetting polyimide resin composition of the present invention in an organic solvent is prepared, and this resin varnish is applied on a support film and heated or blown with hot air or the like. The organic solvent is dried to form a resin composition layer. Conditions such as the organic solvent and drying conditions are the same as those for the adhesive film. The thickness of the resin composition layer is preferably in the range of 5 to 15 μm.

  Next, this adhesive film is laminated on both surfaces of the heat resistant resin film. Lamination conditions are the same as described above. Moreover, if the resin composition layer is previously provided on one side of the heat-resistant film, the lamination may be only on one side. Next, the resin composition layer is cured by heating to form an insulating layer that is a layer of the resin composition. The conditions for heat curing are usually selected in the range of 150 to 220 ° C. for 20 to 180 minutes, more preferably in the range of 160 to 200 ° C. for 30 to 120 minutes.

  A method for producing a flexible circuit board from the base film for the flexible circuit board will be described. In the case of a base film composed of an A ′ layer, a C layer, and an A ′ layer, first, after heat curing, a circuit board is drilled by a method such as drilling, laser, or plasma to form a through hole for conduction on both sides. . In the case of a base film composed of an A ′ layer, a C layer, and a D layer, holes are formed by the same method to form via holes. In particular, drilling with a laser such as a carbon dioxide laser or a YAG laser is generally used.

  Next, a surface treatment of the insulating layer (resin composition layer) is performed. About surface treatment, it is the same as that of the case of the adhesive film mentioned above. After the surface treatment, a conductor layer is formed by plating on the surface of the insulating layer. The formation of the conductor layer by plating is the same as in the case of the adhesive film described above. After the conductor layer is formed, the peel strength of the conductor layer can be further improved and stabilized by annealing at 150 to 200 ° C. for 20 to 90 minutes.

  Next, the conductor layer is patterned to form a circuit to obtain a flexible circuit board. When a base film composed of an A layer, a C layer, and a D layer is used, a circuit is also formed on the copper foil that is the D layer. As a circuit formation method, for example, a subtractive method or a semi-additive method known to those skilled in the art can be used. Details are the same as in the case of the adhesive film described above.

  The single-sided or double-sided flexible circuit board obtained in this way can be produced as a multilayer flexible circuit board by using the adhesive film of the present invention, for example, as described above.

  The resin composition of the present invention is also useful as a material for forming a stress relaxation layer between a semiconductor and a substrate substrate. For example, in the same manner as described above, all or part of the uppermost insulating layer of the substrate substrate is formed by the adhesive film obtained by using the resin composition of the present invention, and the resin is connected by connecting the semiconductor. A semiconductor device in which a semiconductor and a substrate substrate are bonded via a cured product of the composition can be manufactured. In this case, the thickness of the resin composition layer of the adhesive film is appropriately selected within a range of 10 to 1000 μm. The resin composition of the present invention can form a conductor layer by plating, and a circuit pattern can also be produced by simply forming a conductor layer by plating on an insulating layer for stress relaxation provided on a substrate substrate. Is possible.

  EXAMPLES Next, an Example is shown and this invention is demonstrated further in detail. Unless otherwise specified, “part” and “%” are based on mass in the examples.

Synthesis Example 1 [Synthesis of Polyimide Resin (A)]
In a flask equipped with a stirrer, a thermometer and a condenser, 213.2 g of DMAC (dimethylacetamide), 6.28 g (0.036 mol) of TDI (tolylene diisocyanate), TODI (4,4′-diisocyanate-3,3 '-Dimethyl-1,1'-biphenyl) 38.2 g (0.143 mol), TMA (trimellitic anhydride) 29.1 g (0.151 mol), BTDA (benzophenone-3,3', 4,4) ′ -Tetracarboxylic dianhydride) and 12.2 g (0.038 mol) were added, the temperature was raised to 150 ° C. over 1 hour while paying attention to heat generation while stirring, and the reaction was carried out at this temperature for 5 hours. I let you. The reaction proceeded with the foaming of carbon dioxide, and the system became a brown transparent liquid. A polyimide resin solution (resin composition in which the polyimide resin was dissolved in DMAC) having a resin solid content of 25% with a viscosity of 2 Pa · s at 25 ° C. and a solution acid value of 16 (KOHmg / g) was obtained. This is abbreviated as polyimide resin (A1) solution. In addition, the solid content acid value of the resin calculated from the value was 64 (KOHmg / g). Moreover, it was the weight average molecular weight 10,000 as a result of the measurement of a gel permeation chromatography (GPC).

  The obtained polyimide resin (A1) solution was coated on a KBr plate, and the infrared absorption spectrum of the sample obtained by volatilizing the solvent was measured. As a result, 2270 cm-1 which is the characteristic absorption of the isocyanate group completely disappeared, and 725 cm- Characteristic absorption of the imide ring was confirmed at 1, 1780 cm <-1> and 1720 cm <-1>. The amount of carbon dioxide generated was 15.8 g (0.36 mol), which was monitored by the change in the flask content weight. From this, it is concluded that the total amount of 0.36 mol, which is the total amount of isocyanate groups, has been converted to imide bonds and amide bonds.

  Table 1 shows the blending amount of the raw material of the thermosetting polyimide resin (A1), the content of the biphenyl skeleton, the logarithmic viscosity, the weight average molecular weight and the solid content acid value.

Synthesis example 2 (same as above)
Polyimide resin (Synthesis Example 1) except that biphenyl-3,3 ′, 4,4′-tetracarboxylic anhydride (BPDA) was used instead of BTDA, using the blending ratio shown in Table 1. A solution of A2) was obtained. As in Synthesis Example 1, the biphenyl skeleton content, logarithmic viscosity, weight average molecular weight and solid content acid value are shown in Table 1.

Synthesis examples 3 and 7 [same as above]
A solution of thermosetting polyimide resins (A3) to (A5) and thermosetting polyimide resin (A7) was obtained in the same manner as in Synthesis Example 1 except that the mixing ratio shown in Table 1 was used. As in Synthesis Example 1, the biphenyl skeleton content, logarithmic viscosity, weight average molecular weight and solid content acid value are shown in Table 1. HCA-HQ shown in the table is 10- (2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide, and 20% of the GPC area ratio is in the resin. And the rest remained free.

  In Synthesis Examples 1 to 7, TODI is used as an isocyanate raw material having a biphenyl structure and reacted with various acid anhydrides. In Synthesis Example 2, BPDA is used as the acid anhydride raw material. In any case, the infrared spectrum absorption of the isocyanate group cannot be confirmed, and the infrared spectrum absorption of the acid anhydride group is a trace amount in any case, and it is concluded that the reaction is 90% or more. Therefore, it was concluded that the resin structure has a biphenyl skeleton directly connected to the nitrogen atom in the five-membered cyclic imide skeleton.

Synthesis Examples 8 to 13 [Synthesis of Comparative Comparison Polyimide Resin (a)]
The raw materials composition shown in Table 2 is used as a blending ratio, and these raw materials are charged into a flask at a time. The same polyimide resin for comparison (a1 to a6) is used in the same synthesis apparatus, stirring, temperature increase, and reaction time as in Synthesis Example 1. ) Was synthesized. As in Synthesis Example 1, the biphenyl skeleton content, logarithmic viscosity, weight average molecular weight and solid content acid value are shown in Table 1. Regarding Synthesis Example 10, solidification occurred during the synthesis, and the reaction was not possible during the synthesis, and was interrupted. Regarding Synthesis Example 11, turbidity occurred during the synthesis and solidified after the reaction. Therefore, logarithmic viscosity, weight average molecular weight, and solid content acid value could not be measured.

Synthesis example 14 (same as above)
In a flask equipped with a stirrer, 16.10 g (39 mmol) of 2,2-bis [4- (aminophenoxy) phenyl] propane and 1.25 g of 3,3′-dicarboxy-4,4′-diaminodiphenylmethane (5 Mmol) and 1,3-bis (aminophenoxymethyl) -1,1,3,3, -tetramethyldisiloxane (21.25 g, 56 mmol) and 3,3 ′, 4,4′-benzophenonephone tetracarboxylic acid 32.22 g (100 mmol) of dianhydride and 300 ml of N-methyl-2-pyrrolidone (NMP) were introduced at ice temperature and stirring was continued for 1 hour. Next, this solution was reacted at room temperature for 3 hours to synthesize polyamic acid. To the obtained polyamic acid, 50 ml of toluene and 1.0 g of p-toluenesulfonic acid were added and heated to 160 ° C. The imidization reaction was carried out for 3 hours while azeotroping with toluene and separating water. Toluene was distilled off, the resulting polyimide varnish was poured into methanol, and the resulting precipitate was separated, pulverized, washed, and dried to obtain a molecular weight of 18,000, Tg of 150 ° C., and a dielectric constant of 3.0. 62.5 g (93% yield) of siloxane-modified polyimide was obtained. When the infrared absorption spectrum was measured, typical imide absorption was observed at 1718 and 1783 cm ⁻¹ . This polyimide resin is abbreviated as polyimide resin (a7). The polyimide resin (a7) was dissolved in DMAC to obtain a resin solution of a polyimide resin (a7) having a solid content of 30%.

  Examples 1-11 and Comparative Examples 1-6

  The components shown in Tables 3 to 5 were mixed and mixed to prepare a uniform resin solution. The thermosetting polyimide resin compositions 1 to 11 of the present invention and the thermosetting resin for comparison were used. Compositions 1 ′ to 6 ′ were obtained. Each of the composition, the B-staged cured product, and the completely cured product was evaluated as follows. The evaluation method is shown below.

  Evaluation of the composition: solution viscosity, change in viscosity over time, paintability of the composition, film-forming property.

  Evaluation of B-staged cured product: flexibility, curl resistance, and ease of melting of the film.

  Evaluation of fully cured products: heat resistance, mechanical properties, dimensional stability,

(Evaluation of composition)
<Method for evaluating solution viscosity and change in viscosity over time>
The resin composition was allowed to stand for 2 hours after preparation, and the E-type rotational viscosity at 25 ° C. was measured and evaluated. The measurement was performed at 10 rpm and 100 rpm, and the ratio of 10 rpm / 100 rpm was evaluated as thixotropy (TI value). As the viscometer, a TV-22 type viscometer cone plate type (rotor: 3 ° × R9.7) manufactured by Toki Sangyo Co., Ltd. was used. If the TI value is high, the thixotropy is large, and the surface smoothness during coating is poor. The same measurement was performed 20 days after standing at room temperature, and this result was used as the evaluation result of the change in viscosity over time.

<Evaluation method of paintability of composition>
The resin composition was coated on a tin plate with a 0.152 mil applicator in an atmosphere at 25 ° C. The appearance of the coating was evaluated according to the following evaluation criteria.
Evaluation criteria ○: Transparent, glossy and flat surface.
Δ: The surface is uneven and not flat.
X: Phenomenon that the surface is not glossy and the surface is not flat can be confirmed.

<Method for evaluating film-forming properties>
After applying the resin composition to a 100 μm thick PET film with an applicator so that the film thickness after drying is 30 μm, the test piece obtained by drying at 100 ° C. for 10 minutes is left at 25 ° C. for 24 hours, The appearance of the coating film was evaluated according to the following evaluation criteria.
Evaluation criteria ○: No abnormalities such as cracks are observed in the coating film.
Δ: Some cracks are observed in the coating film.
X: Cracks occurred on the entire surface of the coating film.

[B-staged cured product evaluation]
<Method for evaluating flexibility of film>
After applying the resin composition to a 100 μm-thick PET film (width 10 cm, length 20 cm) with an applicator so that the film thickness after drying is 30 μm, a test piece obtained by drying at 100 ° C. for 10 minutes is prepared. After leaving at room temperature for 30 minutes, the coated surface was on the outside and the PET surface was on the inside, and the following evaluation criteria were used.

A: No bending or cracking is observed in the coated resin composition when the PET film laminate is folded with the resin surface facing outside with a metal rod having a diameter of 1 mm on the inside.
◯: No cracks or floats were observed in the resin composition applied when the PET film laminate was folded with the resin surface facing outside with a metal rod having a diameter of 3 mm inside, and returned.
Δ: No cracks or floats were observed in the resin composition applied when the PET film laminate was folded with the metal surface having a diameter of 5 mm on the inside and the resin surface facing outward.
X: Cracks, floats, etc. are observed in the resin composition applied when the PET film laminate is bent with the metal surface having a diameter of 5 mm inside and the resin surface facing outward.

<Curl resistance evaluation method>
After applying the resin composition to a 100 μm-thick PET film (width 10 cm, length 20 cm) with an applicator so that the film thickness after drying is 30 μm, a test piece obtained by drying at 100 ° C. for 10 minutes is prepared. Cut out the painted part into a 5cm square, place it on a flat horizontal plate, leave it at room temperature for 30 minutes, and evaluate it according to the following evaluation criteria with the painted surface facing outward and the PET surface facing inward. did.

(Double-circle): The edge of the sample cut out from the horizontal plate surface is flat and does not float.
(Circle): The float of the edge of the sample cut out from the horizontal plate surface is 5 mm or less.
(Triangle | delta): The float of the edge of the sample cut out from the horizontal plate surface is 10 mm or less.
X: The float of the edge of the sample cut out from the horizontal plate surface is 10 mm or more.

<Evaluation method of meltability>
The ease of melting was evaluated by transferring the B-staged composition to a copper foil under the following conditions, and then observing the state of the transferred composition film and peeling the tape.
(Create film)
The resin composition was uniformly applied on a PET film (thickness: 125 μm) with an applicator so that the thickness of the resin composition layer after drying was 25 μm, and dried at 100 ° C. for 5 minutes to form a film.

(Evaluation method)
The above film was superimposed on an electrolytic copper foil (thickness 18 μm, surface roughness: M surface Rz 7.4 μm, S surface Ra 0.21 μm) preheated to 110 ° C. so that the resin surface was in contact with copper. The resin composition was transferred to the copper surface by hot pressing at a pressure of 1 MPa for 1 minute. Thereafter, the PET film was peeled off, and the resin composition was further cured by heating at 200 ° C. for 60 minutes. The test piece was subjected to a tape peeling test according to JIS K 5400 8.5.2 (adhesive cross-cut tape method) and evaluated according to the following evaluation criteria.

A: The resin is completely transferred to the copper foil at the stage where the PET film is peeled off before the main curing, and the tape is peeled off after the main curing.
○: The resin is completely transferred to the copper foil at the stage where the PET film is peeled off before the main curing, and after the main curing, the tape is peeled off and some defects are observed.
(Triangle | delta): There exists a location where resin has not adhered to copper foil in the stage which peeled PET film before this hardening.
X: The resin did not adhere to the copper foil at all when the PET film was peeled off before the main curing.

[Evaluation of completely cured product]
<Evaluation method of heat resistance (evaluation by solder bath)>
(Preparation of test piece)
The resin composition is coated on a glass epoxy substrate laminated with copper so that the film thickness after curing is 30 μm, dried for 60 minutes with a 200 ° C. dryer, and then cooled to room temperature to produce a cured coating film. did.

(Evaluation method)
The cured coating film was immersed in molten solder at 260 ° C. for 30 seconds and cooled to room temperature. This solder bath immersion operation was performed three times in total, and the appearance of the cured coating film was evaluated according to the following evaluation criteria.

A: Appearance abnormality is not observed in the coating film.
○: Some abnormality such as swelling or peeling is observed in the coating film.
Δ: Abnormalities such as swelling and peeling are often observed in the coating film ×: Abnormalities such as swelling and peeling are observed on the entire surface of the coating film.

<Heat resistance evaluation method (evaluation by measurement of TG)>
(Preparation of test piece)
The resin composition was coated on a tin plate so that the film thickness after curing was 30 μm, dried for 20 minutes with a dryer at 70 ° C., cured for 1 hour at 200 ° C., cooled, and then peeled off. Was cut into a width of 5 mm and a length of 30 mm to prepare a measurement sample.

(Evaluation method)
Using a thermal analysis system TMA-SS6000 manufactured by Seiko Electronics Co., Ltd., measurement was performed by the TMA (Thermal Mechanical Analysis) method under the conditions of a sample length of 10 mm, a heating rate of 10 ° C./min, and a load of 30 mN. In addition, TG calculated | required the inflection point from the temperature-dimension change curve by TMA measurement, and made the temperature TG. It shows that it is excellent in heat resistance, so that TG is high.

<Dimensional stability evaluation method (evaluation by measurement of linear expansion coefficient)>
A test piece was prepared in the same manner as in the above <Heat resistance evaluation method (evaluation by TG measurement)>, and TMA-SS6000 was used for TMA under the conditions of a sample length of 10 mm, a heating rate of 10 ° C./min, and a load of 30 mN. It was measured by (Thermal Mechanical Analysis) method. The temperature range used for the linear expansion coefficient was determined from the sample length displacement at 20 to 200 ° C. The smaller the linear expansion coefficient, the better the dimensional stability.

<Mechanical properties evaluation method>
The mechanical properties were evaluated by conducting a tensile test of the coating film (film) and obtaining the elastic modulus, breaking strength and breaking elongation.
(Preparation of test piece)
It coated on the tinplate board | substrate so that the film thickness of the coating film which can obtain the resin composition 1 might be set to 30 micrometers. Next, this coated plate was dried with a dryer at 50 ° C. for 30 minutes, with a dryer at 100 ° C. for 30 minutes, and with a dryer at 200 ° C. for 60 minutes to form a coating film (film). After cooling to room temperature, the coating film (film) was cut into a predetermined size, isolated from the substrate, and used as a measurement sample.
<Tensile test measurement method>
Five samples for measurement were prepared and subjected to a tensile test under the following conditions to determine the elastic modulus, breaking strength, and breaking elongation. It represents that it is a coating film which is excellent in a softness | flexibility, so that the value of an elasticity modulus is low. It represents that it is a coating film which is excellent in a softness | flexibility, so that the value of breaking elongation is high. And it shows that it is a tough coating film, so that the value of breaking strength is high.
Measuring instrument: Tensilon manufactured by Toyo Baldwin, sample shape: 10 mm x 70 mm, between chucks: 20 mm
Tensile speed: 10 mm / min, measurement atmosphere: 22 ° C., 45% RH

Footnotes in Tables 1 to 6 are blended in terms of solid content.
PBM: Metaphenylene bismaleimide Molecular weight: 268
MPBM: 4-methyl-1,3-phenylenebismaleimide Molecular weight: 282
MPMBM: 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide Molecular weight: 414
DMBM: 4,4′-diphenylmethane bismaleimide Molecular weight: 358
OPBM: Phenylmethane bismaleimide oligomer Structural formula

但しｎは０から１０の混合物 平均分子量：９５０
ＢＰＡＢＭ：ビスフェノールＡジフェニルエーテルビスマレイミド 分子量：５７０
ＴＭＢＰ：テトラメチルビフェニル型エポキシ樹脂 エポキシ当量：１８７
ＢＰＡ：ビスフェノールＡ型エポキシ樹脂 エポキシ当量：
ＮＰ：ナフタレン型エポキシ樹脂 エポキシ当量：１５０
ＩＤＭＢＭ： ＤＭＢＭ（４，４’−ジフェニルメタンビスマレイミド 分子量：３５８）をイソホロンジアミンで鎖伸長させたビスマレイミドオリゴマー 平均分子量：１１５０
ＢＰＡＰ：以下の構造を有するビスフェノールＡ型ビスアリル化合物

Where n is a mixture of 0 to 10 Average molecular weight: 950
BPABM: Bisphenol A diphenyl ether bismaleimide Molecular weight: 570
TMBP: Tetramethylbiphenyl type epoxy resin Epoxy equivalent: 187
BPA: Bisphenol A type epoxy resin Epoxy equivalent:
NP: Naphthalene type epoxy resin Epoxy equivalent: 150
IDMBM: Bismaleimide oligomer obtained by chain extension of DMBM (4,4′-diphenylmethane bismaleimide molecular weight: 358) with isophoronediamine Average molecular weight: 1150
BPAP: bisphenol A type bisallyl compound having the following structure

Footnotes in Table 9 Purination: The resin composition solution loses its fluidity and becomes a soft gel.
In Comparative Examples 3 and 4, since the synthesized resin was solid, it was ground and refined by a mortar and mixed and mixed. This was further heated to 100 ° C. and melted, but it was not uniformly melted and was in a separated state.

Claims (16)

A thermosetting polyimide resin (A) having a biphenyl skeleton directly connected to a nitrogen atom in a 5-membered cyclic imide skeleton, a weight average molecular weight (Mw) of 3,000 to 150,000, and an aromatic ring; A thermosetting polyimide resin composition containing a polymaleimide compound (B) having a molecular weight of 200 to 1,000 ,
The thermosetting polyimide resin characterized in that the content of the biphenyl skeleton in the thermosetting polyimide resin (A) is 20 to 45% by mass and the logarithmic viscosity is 0.1 to 0.9 dl / g. Composition.   The thermosetting polyimide resin composition according to claim 1, wherein the thermosetting polyimide resin (A) is a polyimide resin further having a benzophenone structure. The thermosetting polyimide resin (A) further thermosetting polyimide resin composition according to claim 1 Symbol mounting a polyimide resin having a tolylene structure. The thermosetting polyimide resin composition according to any one of claims 1 to 3 , wherein the thermosetting polyimide resin (A) is a polyimide resin having no alkylene structure. The thermosetting polyimide resin composition according to any one of claims 1 to 4 , wherein the thermosetting polyimide resin (A) is a polyimide resin obtained by reacting a polyisocyanate having a biphenyl skeleton and an acid anhydride. . The thermosetting polyimide resin composition according to claim 5, wherein the polyisocyanate having a biphenyl skeleton is tolidine diisocyanate or polyisocyanate derived from tolidine diisocyanate.   The thermosetting polyimide resin composition according to claim 1, wherein the polymaleimide compound (B) is a bismaleimide compound having a molecular weight of 250 to 600. The thermosetting polyimide resin composition according to claim 7, wherein the bismaleimide compound is a compound represented by the following formula.

[Wherein (R ₂ ) represents a divalent organic group having an aromatic ring. ] The thermosetting polyimide resin composition according to claim 7, wherein the compound is a compound represented by the following formula.

[Wherein, R ₃ represents a single bond or methylene, R ₄ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, respectively, and n is an integer of 0 to 4. ]   The thermosetting polyimide resin composition according to claim 1, wherein the polymaleimide compound (B) is phenylene bismaleimide or methylphenylene bismaleimide.   The thermosetting polyimide resin composition of Claim 1 which contains 5-200 mass parts of polymaleimide compounds (B) with respect to 100 mass parts of polyimide resins (A). Furthermore, any one thermosetting polyimide resin composition according to claim 1 to 11 containing an epoxy resin (C). The epoxy resin (C) is a bisphenol A type epoxy resin, bisphenol F type epoxy resin, claim is at least one epoxy selected from the group consisting of bisphenol S type epoxy resin, biphenyl type epoxy resins and naphthalene type epoxy resin 12 The thermosetting polyimide resin composition described. The thermosetting polyimide resin composition of Claim 12 which contains 5-200 mass parts of polymaleimide compounds (B) with respect to 100 mass parts of polyimide resins (A), and contains 5-200 mass parts of epoxy resins (C). object. A cured product obtained by curing the thermosetting polyimide resin composition according to any one of claims 1 to 14 . Thermosetting polyimide layer formed by the resin composition, the printed wiring board layers adhesive film characterized by having on the carrier film according to any one of claims 1-14.