JP2008101123A - Modified polyimide resin composition, paste composed thereof and electronic device produced therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a modified polyimide resin composition, a paste made of the composition and an electronic device having a solder resist layer, a surface-protection layer, an interlayer insulation layer or an adhesive layer obtained from the composition. <P>SOLUTION: The modified polyimide resin comprises: component (A) a modified polyimide resin obtained by using (a) a trivalent and/or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) a polyol expressed by general formula (1) and (c) an alicyclic polyamine residue derivative as essential components and reacting the components in an organic solvent selected from an ether solvent, an ester solvent, a ketone solvent and an aromatic hydrocarbon solvent; and component (B) an epoxy resin having ≥2 epoxy groups in one molecule, and is produced without using a solvent substitution treatment after the reaction and is essentially free from organic solvents except for the above solvents. The invention further provides a paste composed of the resin composition and an electronic device produced by using the same. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a modified polyimide resin composition having excellent heat resistance, flexibility and sufficient colorless transparency and suitable for a coating method such as a printing press, a dispenser or a spin coater, a paste comprising the same, and a solder obtained therefrom The present invention relates to an electronic component having a resist layer, a surface protective layer, an interlayer insulating layer, or an adhesive layer.

  Currently, flexible printed wiring boards are required for electronic equipment components that require flexibility and small space, for example, between device mounting boards for display devices such as liquid crystal displays and plasma displays, and boards such as mobile phones, digital cameras, and portable game machines. Widely used for relay cables, operation switch board, etc. On the other hand, with the development of foldable paper displays and the like, there is an increasing need for a transparent film substrate to replace the current glass substrate. Therefore, flexible printed wiring boards are considered to be applied to transparent film substrates. For such applications, all-aromatic polyimides currently used in flexible printed wiring boards (trade name Kaneka Corporation) Manufactured by Apical etc. are not applicable because they are colored yellowish brown. Therefore, various colorless and transparent polyimide resins that can be used for such applications have been proposed.

  On the other hand, in order to use a polyimide resin as a solder resist layer, a surface protective layer, an interlayer insulating layer, or an adhesive layer, a solvent solubility is required, and therefore a composition comprising a solvent-soluble ring-closing polyimide resin has been proposed. . However, conventionally, a high boiling nitrogen-based polar solvent such as N-methyl-2-pyrrolidone has been used as a solvent for varnishing, and therefore high temperature curing of 200 ° C. or higher is required at the time of drying / curing. There was a problem that the thermal degradation of the. In addition, when the varnish is applied to the substrate and then left standing for a long time, there is a problem that ink, whitening of the coating film, and voids are generated due to moisture absorption of the high boiling point nitrogen-based solvent, and the working conditions become complicated.

  Furthermore, since the polyimide resin is generally hard with a high elastic modulus, there is a problem when it is laminated on a substrate such as a film or a copper foil because warpage or the like is generated due to a difference in elastic modulus. In addition, the cured film lacks flexibility and has a problem of poor flexibility.

Examples of polyimide resins that are soluble in non-nitrogen solvents and have low warpage and flexibility by making the resin flexible and have a low elastic modulus include, for example, Patent Document 1, Patent Document 2, and the like. A resin is disclosed.
These polysiloxane-modified polyimide resins use a diamine having an expensive dimethylsiloxane bond as a starting material for reducing the elastic modulus, and are inferior in economic efficiency. In addition, as the amount of polysiloxane copolymerized increases, there is a problem that adhesion, solvent resistance, and chemical resistance decrease.

  In order to improve these defects, for example, Patent Document 3 discloses a paste using a polycarbonate-modified polyimide resin.

  The polycarbonate-modified polyimide resin disclosed here has improved defects derived from polysiloxane and has good printability, but the paste obtained from this resin is still suitable for applications such as transparent substrates. Applicable colorless transparency cannot be obtained.

  As a polyimide resin that is soluble in a non-nitrogen solvent and has a transparent resin, in Patent Document 4, Patent Document 5, and Patent Document 6, the light transmittance at a wavelength of 500 nm with a dry film thickness of 30 μm is 75% or more. A polyimide resin composition and its varnish are disclosed. (Patent Document 7) discloses a polyimide resin having a light transmittance of 81% or more at 400 nm when a film having a thickness of 25 μm is formed. The polyimide resin disclosed here is colorless and transparent and excellent in solubility in a non-nitrogen solvent, but has a high elastic modulus, so that warpage in the case of a laminate is large and poor in flexibility. Furthermore, no mention is made of solder heat resistance and printability.

On the other hand, Patent Document 8 contains at least one component selected from the group consisting of polyether, polyester, polyacrylonitrile-butadiene copolymer, polycarbonate diol and dimer acid as a copolymer component, and has an isophorone residue. A polyimide resin having a monomer as an essential component is disclosed. Although the polyimide resin disclosed herein is expected to be colorless and transparent and excellent in solubility in non-nitrogen solvents, as a transparent film substrate intended for the present invention, warpage, solder heat resistance and printing It does not satisfy aptitude at the same time. Further, if the reaction solvent is used as it is, the stability of the varnish is low, and the resin is likely to precipitate with time, and for the purpose of use, total substitution with a low-boiling solvent having higher solubility is performed, resulting in poor economic efficiency.
JP 7-304950 A JP-A-8-333455 Japanese Patent Laid-Open No. 11-12500 Japanese Patent Laid-Open No. 8-113646 JP-A-8-283356 JP 2002-275263 A JP 2003-238707 A JP 2003-289594 A

  As can be seen from these examples, in the conventional techniques so far, (1) colorless transparency (2) non-nitrogen solvent solubility (3) low temperature drying / curing property (4) low warpage (5) flexibility (6 ) A polyimide resin composition applicable as a solder resist layer, a surface protective layer, an interlayer insulating layer or an adhesive layer for a transparent substrate that satisfies printability has not been obtained. The present invention eliminates the above-mentioned problems of the prior art, and (1) colorless and transparent (2) non-nitrogen solvent solubility (3) low temperature drying / curability (4) low warpage (5) flexibility ( 6) Modified polyimide resin composition with excellent printability, heat resistance, chemical resistance, electrical properties, workability and economy, paste comprising the same and solder resist layer, surface protective layer, interlayer insulating layer obtained therefrom It is an object to provide an electronic component having an adhesive layer.

As a result of intensive studies in order to solve the above problems, the present inventors have finally completed the present invention. That is, this invention consists of the following structures.
(1) As component (A), (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) a polyol represented by the following general formula (1), (c) fat A modified polyimide resin obtained by reacting in an organic solvent selected from an ether solvent, an ester solvent, a ketone solvent and an aromatic hydrocarbon solvent, with the cyclic polyamine residue derivative as an essential component,
(B) As an ingredient, an epoxy resin having two or more epoxy groups per molecule,
A modified polyimide resin composition characterized in that it contains no organic solvent other than those mentioned above, and does not undergo solvent substitution after the reaction.

［式中、ｍ，ｎはそれぞれ独立に１〜４０の整数であり、Ｒは炭素数１〜２２のアルキレン基又はアリーレン基を示す］

[Wherein, m and n are each independently an integer of 1 to 40, and R represents an alkylene group or an arylene group having 1 to 22 carbon atoms]

(2) The light transmittance at 400 nm is 65% or more in a film shape having a thickness of 20 μm obtained by drying and curing the solvent, the elongation at break at 25 ° C. is 70% or more, and the tensile elastic modulus is 1.2 GPa or less. The modified polyimide resin composition according to the above (1).

(3) The modified polyimide resin composition according to (1), further containing an inorganic or organic filler as component (C) and having thixotropy of 1.3 or more in terms of the degree of change.

(4) A paste comprising the modified polyimide resin composition according to (2) or (3).

(5) An electronic component having a solder resist layer, a surface protective layer, an interlayer insulating layer, or an adhesive layer obtained by drying and curing the modified polyimide resin composition or paste according to any one of claims 1 to 4.

  According to the present invention, (1) colorless transparency (2) non-nitrogen solvent solubility (3) low temperature drying / curability (4) low warpage (5) flexibility (6) ) Modified polyimide resin composition with excellent printability and excellent heat resistance, chemical resistance, electrical properties, workability and economy, paste composed thereof and solder resist layer, surface protective layer, interlayer insulating layer obtained therefrom Since an electronic component having an adhesive layer can be provided, it is important to contribute to the industry.

The present invention will be described in detail below.
The modified polyimide resin composition of the present invention and the paste comprising the same are a modified polyimide resin as component (A), an epoxy resin having two or more epoxy groups per molecule as component (B), or a component (C). As an inorganic or organic filler.

<Modified polyimide resin (A) component>
The modified polyimide resin of component (A) used in the present invention is a method of producing from a polycarboxylic acid component having an acid anhydride group and an isocyanate component (isocyanate method), or a polycarboxylic acid component having an acid anhydride group It is produced by a known method such as a method (direct method) in which an amine is reacted to form an amic acid, followed by ring closure. Industrially, the isocyanate method is advantageous.

  As the component (a) constituting the modified polyimide resin used in the present invention, a trivalent or tetravalent polycarboxylic acid having an acid anhydride group that generally reacts with an isocyanate component or an amine component to form a polyimide resin. Derivatives are used. Examples of aromatic polycarboxylic acid derivatives include trimellitic anhydride, pyromellitic dianhydride, ethylene glycol bisanhydro trimellitate, propylene glycol bisanhydro trimellitate, 1,4-butanediol bisanhydro. Alkylene glycol bisanhydro trimellitate such as trimellitate, hexamethylene glycol bisanhydro trimellitate, polyethylene glycol bisanhydro trimellitate, polypropylene glycol bisanhydro trimellitate, 3,3 ', 4,4 '-Benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5 8-Naphthalenetetracarboxylic dianhydride 2,3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylsulfone tetracarboxylic dianhydride , M-terphenyl-3,3 ', 4,4'-tetracarboxylic dianhydride, 4,4'-oxydiphthalic dianhydride, 1,1,1,3,3,3-hexafluoro- 2,2-bis (2,3- or 3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3- or 3,4-dicarboxyphenyl) propane dianhydride, 2, 2-bis [4- (2,3- or 3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis [4- (2,3- or 3,4-dicarboxyphenoxy) phenyl] propane Examples thereof include dianhydrides and 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldisiloxane dianhydride.

  Examples of the aliphatic or alicyclic polycarboxylic acid derivatives include butane-1,2,3,4-tetracarboxylic dianhydride, pentane-1,2,4,5-tetracarboxylic dianhydride, and cyclobutane. Tetracarboxylic dianhydride, hexahydropyromellitic dianhydride, cyclohex-1-ene-2,3,5,6-tetracarboxylic dianhydride, 3-ethylcyclohex-1-ene-3- ( 1,2), 5,6-tetracarboxylic dianhydride, 1-methyl-3-ethylcyclohexane-3- (1,2), 5,6-tetracarboxylic dianhydride, 1-methyl-3- Ethylcyclohex-1-ene-3- (1,2), 5,6-tetracarboxylic dianhydride, 1-ethylcyclohexane-1- (1,2), 3,4-tetracarboxylic dianhydride 1-propylcyclohe Sun-1- (2,3), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane-1- (2,3), 3- (2,3) -tetracarboxylic dianhydride , Dicyclohexyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic dianhydride, 1-propylcyclohexane -1- (2,3), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane-1- (2,3), 3- (2,3) -tetracarboxylic dianhydride , Dicyclohexyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2.2 .2] Octane-2,3,5,6-tetracarboxylic dianhydride , Bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, hexahydroterephthalic trimellitic anhydride, and the like.

  These trivalent or tetravalent polycarboxylic acid derivatives may be used alone or in combination of two or more. In view of heat resistance, transparency, adhesion, cost, etc., pyromellitic dianhydride and trimellitic anhydride are preferable, and trimellitic anhydride is more preferable.

  In the modified polyimide resin used in the present invention, aliphatic, alicyclic, and aromatic polycarboxylic acids may be further copolymerized as necessary as long as the target performance is not impaired. Examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedioic acid, dodecanedioic acid, eicosanedioic acid, 2-methylsuccinic acid, 2-methyladipic acid, 3 -Methyladipic acid, 3-methylpentanedicarboxylic acid, 2-methyloctanedicarboxylic acid, 3,8-dimethyldecanedicarboxylic acid, 3,7-dimethyldecanedicarboxylic acid, 9,12-dimethyleicosane diacid, fumaric acid, Examples of the alicyclic dicarboxylic acid such as maleic acid, dimer acid, hydrogenated dimer acid, etc. include 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4,4′- Examples of aromatic dicarboxylic acids such as dicyclohexyl dicarboxylic acid include isophthalic acid, Refutaru acid, orthophthalic acid, naphthalenedicarboxylic acid, oxydibenzoic acid, stilbene dicarboxylic acid and the like. These dicarboxylic acids may be used alone or in combination of two or more. Considering heat resistance, transparency, adhesion, cost, etc., 1,4-cyclohexanedicarboxylic acid and dimer acid are preferable, and 1,4-cyclohexanedicarboxylic acid is more preferable. In the present invention, the copolymerization amount of cyclohexanedicarboxylic acid is preferably 15 mol% or more. When the copolymerization amount of cyclohexanedicarboxylic acid is less than 15 mol%, the coloring becomes large and may not be used for optical applications.

  The polycaprolactone diol of the component (b) represented by the general formula (1) constituting the modified polyimide resin used in the present invention has flexibility, low warpage, solubility, etc. to the polyimide resin. Copolymerized as a flexible component to be applied. By copolymerizing these, the elastic modulus of the resin is lowered, and the solubility (varnish) stability in a non-nitrogen solvent used as a polymerization solvent is increased.

  For example, what is marketed as Daicel Chemical Industries, Ltd. brand name PLACEL is mentioned. A number average molecular weight of 300-5000 is used. If the molecular weight is less than 300, flexibility and low warpage are insufficient, and if it exceeds 5000, the modification reaction may not proceed.

  The copolymerization amount of the component (b) is preferably 20% by weight or more and 65% by weight or less, more preferably 30% by weight or more and 50% by weight or less, based on the modified polyimide resin. . If it is less than 30% by weight, the elastic modulus does not sufficiently decrease, and warpage occurs when laminated, and the solubility in non-nitrogen solvents decreases, so that the resin precipitates within 5 months at 30 ° C to 30 ° C. There is a risk of coming. This is particularly remarkable when γ-butyrolactone or cyclohexanone preferably used in the present invention is used as a solvent. On the other hand, if it exceeds 65% by weight, mechanical properties and heat resistance may be deteriorated.

  In the present invention, in addition to the polycaprolactone diols, other flexible components may be copolymerized as necessary as long as the target performance is not impaired. For example, aliphatic / aromatic polyester diols (trade name VYLON220 manufactured by Toyobo Co., Ltd.), aliphatic / aromatic polycarbonate diols (trade name PLACEL-CD220 manufactured by Daicel Chemical Industries, Ltd.), carboxy-modified Examples include acrylonitrile butadiene rubbers (manufactured by Ube Industries, trade name Hycar CTBN 1300 × 13), polysiloxane derivatives such as polydimethylsiloxane diol, polymethylphenylsiloxane diol, and carboxy-modified polydimethylsiloxanes.

  As the (c) component alicyclic polyamine residue derivative constituting the modified polyimide resin used in the present invention, polyisocyanates include, for example, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, transcyclohexane-1,4. -Diisocyanate, hydrogenated m-xylylene diisocyanate, etc. are mentioned. Considering heat resistance, transparency, adhesion, cost, etc., isophorone diisocyanate and 4,4′-dicyclohexylmethane diisocyanate are preferable.

  In addition, in the modified polyimide resin used in the present invention, in addition to the alicyclic polyisocyanate, a polyisocyanate that gives an aromatic or aliphatic polyamine residue may be used as long as the desired performance is not impaired. It may be copolymerized. As aromatic polyisocyanates, for example, diphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- or 5,2'- or 5,3 '-Or 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- or 5, 2'- or 5,3'- or 6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4 , 3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-3 , 3'-Diisocyanate Diphenylmethane-3,4'-diisocyanate, diphenylether-4,4'-diisocyanate, benzophenone-4,4'-diisocyanate, diphenylsulfone-4,4'-diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6 -Diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, naphthalene-2,6-diisocyanate, 4,4 '-[2,2bis (4-phenoxyphenyl) propane] diisocyanate, 3,3' or 2, 2'-dimethylbiphenyl-4,4'-diisocyanate, 3,3'- or 2,2'-diethylbiphenyl-4,4'-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 3, , 3'-diethoxy Phenyl-4,4'-diisocyanate.

  Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate. The copolymerization amount of these aromatic and aliphatic polyisocyanates is usually preferably 20 mol% or less, more preferably 10 mol% or less, based on the total isocyanate amount. When it exceeds 20 mol%, transparency and heat resistance are often impaired.

  Further, a polyisocyanate having 3 or more functional groups may be used, and a polyisocyanate stabilized with a blocking agent necessary for avoiding a change with time may be used. Examples of the blocking agent include alcohol, phenol and oxime, but there is no particular limitation. These polyisocyanates may be used alone or in combination of two or more. When the polymerization is carried out with an excess of isocyanate, the isocyanate group at the end of the resin can be blocked with a blocking agent such as alcohols, lactams or oximes after completion of the polymerization.

  When the modified polyimide resin used in the present invention is produced by a direct method, as the alicyclic polyamine residue derivative of component (c), polyamines include, for example, isophorone diamine, 1,4-transcyclohexane diamine, 4, Examples include 4'-diaminodicyclohexylmethane, hydrogenated m-xylylenediamine and the like. These polyamines may be used alone or in combination of two or more. Moreover, you may copolymerize aromatic and aliphatic diamine as needed in the range which does not impair the target performance.

  In the case of the isocyanate method, the (a) component trivalent or tetravalent polycarboxylic acid derivative having an acid anhydride group, the (b) component polycaprolactone diol represented by the general formula (1), and the (c) component The amount of the polyisocyanate that gives the polyamine residue is such that the number of acid anhydride groups, the number of carboxylic acid groups, and the ratio of the number of hydroxyl groups to the number of isocyanate groups are: isocyanate group number / acid anhydride group number + carboxylic acid group number + hydroxyl group number = 0.80. It is preferable to be 1.20. If it is less than 0.8 or exceeds 1.20, it will be difficult to increase the molecular weight of the modified polyimide resin, and the heat resistance may be lowered or the coating film may be brittle.

  The polymerization reaction of the modified polyimide resin used in the present invention is generated free in the presence of an organic solvent selected from an ether solvent, an ester solvent, a ketone solvent and an aromatic hydrocarbon solvent, for example, in the isocyanate method. It is carried out by heat condensation while removing the coming carbon dioxide gas from the reaction system.

  Examples of the solvent include ether solvents such as diethylene glycol dimethyl ether (diglyme), diethylene glycol diethyl ether (ethyl diglyme), triethylene glycol dimethyl ether (triglyme), and triethylene glycol diethyl ether (ethyl triglyme). Examples of ketone solvents such as methyl isobutyl ketone, cyclopentanone, cyclohexanone, isophorone, and the like, and aromatic hydrocarbon solvents such as toluene, xylene, and solvesso. These may be used alone or in combination of two or more.

  When producing the modified polyimide resin used in the present invention, it is preferable to select and use a solvent that dissolves the resin to be formed. After polymerization, a suitable solvent for the composition and paste should be used as it is. Further preferred. In this case, complicated operations such as solvent replacement are eliminated, and it becomes possible to manufacture at low cost. The boiling point is preferably 140 ° C or higher and 230 ° C or lower. When the temperature is lower than 140 ° C., the solvent may be volatilized during the polymerization reaction. In addition, when screen printing is performed, for example, the solvent volatilization may quickly cause clogging. When it exceeds 230 ° C., it becomes difficult to impart low temperature drying / curing properties. Γ-butyrolactone and cyclohexanone are preferred for relatively high volatility, imparting low temperature drying / curing properties, excellent varnish stability, and conducting the reaction in a homogeneous system efficiently.

  The amount of solvent used is preferably 0.8 to 5.0 times (weight ratio) of the modified polyimide resin to be produced. If it is less than 0.8 times, the viscosity at the time of synthesis is too high, and the synthesis tends to be difficult due to the inability to stir. If it exceeds 5.0 times, the reaction rate tends to decrease.

  In the case of the isocyanate method, the reaction temperature is preferably 70 to 210 ° C, more preferably 100 to 190 ° C, and particularly preferably 120 to 180 ° C. If it is less than 80 ° C., the reaction time becomes too long, and if it exceeds 210 ° C., a three-dimensional reaction occurs during the reaction and gelation tends to occur. The reaction time can be appropriately selected depending on the scale of the batch and the reaction conditions employed.

  In the case of the isocyanate method, amines such as triethylamine, lutidine, picoline, undecene, triethylenediamine, lithium methylate, sodium methylate, sodium ethylate, potassium butoxide, potassium fluoride, sodium fluoride are used to accelerate the reaction. The reaction may be carried out in the presence of a catalyst such as an alkali metal such as alkali metal, an alkaline earth metal compound, a metal such as titanium, cobalt, tin, or zinc, or a metalloid compound. Those having an alkali metal or halogen in the molecule, such as potassium fluoride and sodium methylate, are preferred because of high catalytic activity.

  As a manufacturing method of the modified polyimide resin used in the present invention, in the case of the isocyanate method, for example, (1) (a) component, (b) component and (c) component are used at a time and reacted for modification. (2) After obtaining a modified imide oligomer having an isocyanate group at the terminal by reacting the component (a) and / or the component (b) with an excessive amount of the component (c), a) a method of adding a component and / or (b) component and reacting to obtain a modified polyimide resin; (3) reacting an excess amount of the component (a) and / or component (b) with the component (c); And a modified imide oligomer having a carboxylic acid group and / or an acid anhydride group and / or a hydroxyl group at the terminal is synthesized, and then a component (c) is added and reacted to obtain a modified polyimide resin.

  The logarithmic viscosity of the modified polyimide resin used in the present invention is preferably from 0.1 dl / g to 2.0 dl / g, and more preferably from 0.2 dl / g to 1.8 dl / g. When the logarithmic viscosity is 0.1 dl / g or less, the heat resistance may be lowered or the coating film may be brittle. In addition, the tackiness of the paste is strong and the separation of the plate is poor. On the other hand, at 2.0 dl / g or more, it becomes difficult to dissolve in a solvent, and it tends to become insoluble during polymerization. In addition, the viscosity of the varnish becomes high and handling becomes difficult, and the adhesion to the base material decreases. Furthermore, the nonvolatile content concentration of the paste cannot be increased, and it becomes difficult to form a thick film.

  The glass transition temperature of the modified polyimide resin used in the present invention is preferably 80 ° C. or higher. More preferably, it is 130 degreeC or more, Most preferably, it is 180 degreeC or more. If it is 80 ° C. or lower, the heat resistance is insufficient when used in optical applications, and the resin may be blocked. Although an upper limit is not specifically limited, 400 degreeC or less is preferable from a solvent solubility viewpoint.

<Epoxy resin (B) component>
Examples of the epoxy resin of component (B) used in the present invention include bisphenol A type epoxy resins such as trade name Epicoat 828 and 1001 manufactured by Yuka Shell Epoxy Co., Ltd., and trade name ST manufactured by Tohto Kasei Co., Ltd. -Hydrogenated bisphenol A type epoxy resins such as 2004 and 2007, trade name YDF-170 manufactured by Toto Kasei Co., Ltd., bisphenol F type epoxy resins such as 2004, product names YDB-400 and 600 manufactured by Toto Kasei Co., Ltd. Brominated bisphenol A type epoxy resins such as Equat Shell Epoxy Co., Ltd., Epicoat 152, 154, Nippon Kayaku Co., Ltd., trade name EPPN-201, BREN, Dow Chemical Co., Ltd., trade name DEN Phenolic novolac type epoxy resin such as -438, trade name YDCN-702, 703 manufactured by Toto Kasei Co., Ltd., trade name EOCN manufactured by Nippon Kayaku Co., Ltd. 125S, 103S, 104S, etc. o-cresol novolac type epoxy resins, Todo Kasei Co., Ltd. trade name YD-171 etc., flexible epoxy resin, Yuka Shell Epoxy Co., Ltd. trade name Epon 1031S, Ciba Trade names Araldite 0163 manufactured by Specialty Chemicals Co., Ltd., trade names Denacol EX-611, EX-614, EX-622, EX-512, EX-521, EX-521, EX- manufactured by Nagase Chemtech Co., Ltd. 411, EX-321 polyfunctional epoxy resin, Yuka Shell Epoxy Co., Ltd. trade name Epicoat 604, Toto Kasei Co., Ltd. trade name YH-434, Mitsubishi Gas Chemical Co., Ltd. trade name TETRAD -X, TETRAD-C, Nippon Kayaku Co., Ltd. trade name GAN, Sumitomo Chemical Co., Ltd. trade name ELM-120, and other amine type epoxy resins, Heterocyclic epoxy resins such as the product name Araldite PT810 manufactured by Peachty Chemicals, Inc., the product names Celoxide 2021, EHPE3150 manufactured by Daicel Chemical Industries, Ltd., ERL4234 manufactured by UCC, etc., Dainippon Bisphenol S type epoxy resin such as Epiklon EXA-1514 manufactured by Ink Chemical Industry Co., Ltd., Triglycidyl isocyanurate such as TEPIC manufactured by Nissan Chemical Industry Co., Ltd., trade name YX manufactured by Yuka Shell Epoxy Co., Ltd. Bisphenol-type epoxy resins such as -4000 and bisphenol-type epoxy resins such as YL-6056 manufactured by Yuka Shell Epoxy Co., Ltd., and the like may be used alone or in combination of two or more. Absent.

  Among these epoxy resins, phenol novolac type epoxy resins having more than two epoxy groups in one molecule, o-cresol novolac type epoxy resins, and amine type epoxy resins have solvent resistance, chemical resistance, and moisture resistance. It is preferable in terms of improvement.

  The amount of the (B) component epoxy resin used in the present invention is preferably 1 to 50 parts by weight, more preferably 2 to 40 parts by weight, especially 100 parts by weight of the modified polyimide resin (A). Preferably it is 3-30 mass parts. When the amount of the epoxy resin is less than 1 part by mass, solder heat resistance, solvent resistance, chemical resistance, and moisture resistance tend to decrease. When the amount exceeds 50 parts by mass, mechanical properties, heat resistance, varnish stability and The compatibility with the modified polyimide resin tends to decrease.

  The epoxy resin of component (B) used in the present invention may further contain an epoxy compound having only one epoxy group in one molecule as a diluent.

  As an addition method of the epoxy resin, it may be added after dissolving the epoxy resin added in advance in the same solvent as the solvent contained in the modified polyimide resin, or may be added directly to the modified polyimide resin. .

In order to further improve the properties such as adhesion, chemical resistance and heat resistance, an epoxy resin curing agent may be used in combination. Specific examples of such epoxy resin curing agents, for example, Shikoku Chemicals _{Corp., 2MZ, 2E4MZ, C 11 Z} , C 17 Z, 2PZ, 1B2MZ, 2MZ-CN, 2E4MZ-CN, C 11 Z -CN, 2PZ-CN, 2PHZ- CN, 2MZ-CNS, 2E4MZ-CNS, 2PZ-CNS, 2MZ-AZINE, 2E4MZ-AZINE, C 11 Z -AZINE, 2MA-OK, 2P4MHZ, 2PHZ, imidazole derivatives such 2P4BHZ , Guanamines such as acetoguanamine and benzoguanamine, polyaminos such as diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, melamine and polybasic hydrazides, organic acid salts thereof and / Or d Xiaduct, amine complex of boron trifluoride, triazine derivatives such as ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4-diamino-6-xylyl-S-triazine, trimethylamine, triethanol Amine, N, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) melamine, 2,4,6-tris (dimethylaminophenol), tetramethylguanidine, m- Tertiary amines such as aminophenol, polyvinylphenol, polyvinylphenol bromide, organic phosphines such as tributylphosphine, triphenylphosphine, tris-2-cyanoethylphosphine, tri-n-butyl (2,5-dihydroxyphenyl) phosphonium The Quaternary phosphonium salts such as romide, hexadecyltributylphosphonium chloride, quaternary ammonium salts such as benzyltrimethylammonium chloride, phenyltributylammonium chloride, the polycarboxylic acid anhydride, diphenyliodonium tetrafluoroboroate, triphenylsulfonium hexafluoroantimony Photocationic polymerization catalysts such as Nate, 2,4,6-triphenylthiopyrylium hexafluorophosphate, Irgacure 261 (manufactured by Ciba Specialty Chemicals), Optoma-SP-170 (manufactured by ADEKA) , Styrene-maleic anhydride resin, equimolar reaction product of phenyl isocyanate and dimethylamine, and organic polymethylene such as tolylene diisocyanate and isophorone diisocyanate. Such as equimolar reaction product of cyanate and dimethylamine, it is like hardeners or curing accelerators such conventionally known, may be used in combination singly, or two or more kinds.

  The amount of the epoxy resin curing agent used is preferably 0 to 10 parts by weight, more preferably 0 to 5 parts by weight, based on 100 parts by weight of the epoxy compound.

<Inorganic or organic fine particle (C) component>
To the modified polyimide resin composition of the present invention, an inorganic or organic filler is added as the component (C) in order to improve the workability during coating and printing and the film properties before and after film formation.

The inorganic or organic filler used in the present invention is not particularly limited as long as it can be dispersed in the above-described modified polyimide resin to form a paste and can impart thixotropic properties to the paste. Examples of such inorganic fillers include silica (SiO ₂ ), alumina (Al ₂ O ₃ ), titania (TiO ₂ ), tantalum oxide (Ta ₂ O ₅ ), zirconia (ZrO ₂ ), and silicon nitride (Si ₃ ). N ₄ ), barium titanate (BaO · TiO ₂ ), barium carbonate (BaCO ₃ ), lead titanate (PbO · TiO ₂ ), lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT), gallium oxide (Ga ₂ O _3), spinel _{(MgO · Al 2 O 3)} , mullite _{(3Al 2 O 3 · 2SiO 2} ), cordierite _{(2MgO · 2Al 2 O 3 ·} 5SiO 2), talc (3MgO · 4SiO ₂ · H ₂ O), aluminum titanate _{(TiO 2 -Al 2 O 3)} , yttria-containing zirconia _{(Y 2 O 3 -ZrO 2)} , silicate barium (BaO · 8S O _2), boron nitride (BN), calcium carbonate (CaCO _3), calcium sulfate (CaSO _4), zinc oxide (ZnO), magnesium titanate (MgO · TiO _2), barium sulfate (BaSO _4), organic bentonite, Carbon (C) or the like can be used, and these may be used alone or in combination of two or more.

  From the viewpoint of imparting color tone, transparency, and thixotropy of the obtained paste, silica fine particles (trade name Aerogel manufactured by Nippon Aerosil Co., Ltd.) are preferable.

  The inorganic filler used in the present invention preferably has an average particle size of 50 μm or less and a maximum particle size of 100 μm or less. When the average particle diameter exceeds 50 μm, it becomes difficult to obtain a paste having sufficient thixotropy, and when the maximum particle diameter exceeds 100 μm, the appearance and adhesion of the coating film tend to be insufficient.

  The organic filler used in the present invention is not limited as long as it can be dispersed in the above-described modified polyimide resin solution to form a paste and can impart thixotropic properties to the paste. Polyimide resin particles, benzoguanamine resin particles, epoxy resin Particles and the like.

  The amount of the inorganic or organic filler used in the present invention is preferably 1 to 25% by mass when the entire nonvolatile content of the modified polyimide resin paste is 100% by mass. More preferably, it is 2-15 mass%, Most preferably, it is 3-12 mass%. If the blending amount of the inorganic or organic filler is less than 1 part by mass, the printability tends to decrease, and if it exceeds 25% by mass, the mechanical properties such as the flexibility of the coating film and the transparency tend to decrease.

<Modified polyimide resin composition and paste comprising the same>
The modified polyimide resin composition of the present invention and the paste comprising the same preferably contain the above-mentioned components (A), (B), (C) and other compounding components in the above proportions, roll mill, mixer, etc. There is no particular limitation as long as it is a method that can be obtained by mixing uniformly and can obtain sufficient dispersion. Multiple kneading with three rolls is preferred.

  The modified polyimide resin composition of the present invention and the paste comprising the same preferably have a viscosity in a B-type viscometer in the range of 50 dPa · s to 1000 dPa · s at 25 ° C., and more preferably in the range of 100 dPa · s to 800 dPa · s. . When the viscosity is less than 50 dPa · s, there is a tendency for the paste to flow out after printing and the film thickness to be reduced. When the viscosity exceeds 1000 Pa · s, during printing, the transferability of the paste to the base material is reduced, causing blurring, and voids and pinholes in the printed film tend to increase.

  The throttling property (thixotropic property) is also important, and is preferably 1.3 or more, more preferably 2.0 or more in the measurement method described later. The upper limit is preferably 7.0 or less, and more preferably 6.0 or less. If the degree of change is less than 1.3, the flow of paste after printing becomes large and the film thickness tends to be reduced. If it exceeds 7.0, the paste tends not to flow.

  For the modified polyimide resin composition of the present invention and the paste comprising the same, known phthalocyanine blue, phthalocyanine green, iodin green, disazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, etc. Conventional colorants, known conventional polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol, phenothiazine, etc., known conventional thickeners such as asbestos, olben, benton, montmorillonite, silicone-based, fluorine-based, Defoaming agents such as polymers, leveling agents, imidazole-based, thiazole-based, triazole-based, organoaluminum compounds, organotitanium compounds, organosilane compounds, and other coupling agents / adhesion imparting agents, phosphoric acid esters Known and commonly used additives such as flame retardants such as stealth, melamine phosphate, phosphazene, brominated epoxy and antimony trioxide, flame retardant aids, heat stabilizers, antioxidants and lubricants can be used.

<Curing coating>
The modified polyimide resin composition of the present invention and the paste comprising the same are cured, for example, as a solder resist as follows to obtain a cured product. That is, the composition of the present invention is applied to a flexible printed wiring board with a film thickness of 10 to 160 μm by a screen printing method, a spray method, a roll coating method, an electrostatic coating method, a curtain coating method, etc. After preliminary drying at 60 to 120 ° C., the film is finally dried at 120 to 200 ° C. Drying may be in air or in an inert atmosphere.

  The modified polyimide resin composition of the present invention and the paste comprising the same are required to have a light transmittance of 65% or more at a wavelength of 400 nm of a dried and cured film having a thickness of 20 μm. Preferably it is 75% or more, More preferably, it is 80% or more. If it is less than 65%, there is no problem in using it in applications where transparency is not required, but there is a possibility that problems may arise when it is used in applications that require outstanding transparency, such as a transparent substrate intended for the present invention. is there.

  The modified polyimide resin composition of the present invention and the paste comprising the same are required to have a breaking elongation at 25 ° C. of 70% or more of a dry-cured film having a thickness of 20 μm. Preferably it is 120% or more, More preferably, it is 150% or more. If it is less than 70%, sufficient flexibility as a coating film may not be ensured.

  The modified polyimide resin composition of the present invention and the paste comprising the same are required to have a tensile elastic modulus at 25 ° C. of 1.2 GPa or less of a dried and cured film having a thickness of 20 μm. Preferably it is 1.0 GPa or less, More preferably, it is 0.8 GPa or less. If it exceeds 1.2 GPa, warping may occur when laminated.

The thus obtained modified polyimide resin composition of the present invention and the paste comprising the same are useful as a film forming material for semiconductor elements, overcoat inks for various electronic components, solder resist inks, interlayer insulating films, etc. It can also be used as a paint, a coating agent, an adhesive and the like.

  In order to describe the present invention more specifically, examples will be given below, but the present invention is not limited to the examples. In addition, the measured value described in the Example is measured by the following method.

<Logarithmic viscosity>
The modified polyimide resin was dissolved in N-methyl-2-pyrrolidone so that the polymer concentration was 0.5 g / dl, and the solution viscosity was measured with an Ubbelohde viscosity tube at 30 ° C.
The logarithmic viscosity was defined by the following formula.
(Logarithmic viscosity) = (lnηrel) / C
ln: natural logarithm,
ηrel: the viscosity ratio (−) of the solution to the pure solvent by solvent fall time measurement,
C: Solution concentration (g / dl)

<Fluctuation (thixo ratio)>
Using a Brookfield BH rotational viscometer, the measurement was performed in the following procedure. The resin composition or paste was placed in a wide-mouthed light-shielding bottle (100 ml), and the liquid temperature was adjusted to 25 ° C. ± 0.5 ° C. using a constant temperature water bath. Subsequently, after stirring 40 times over 12 to 15 seconds using a glass rod, a predetermined rotor was installed, allowed to stand for 5 minutes, and then the scale when rotated at 20 rpm for 3 minutes was read. The viscosity was calculated by multiplying this scale by the coefficient in the conversion table. Similarly, the following formula was calculated from the viscosity value measured at 25 ° C. and 2 rpm.
Deflection = viscosity (2 rpm) / viscosity (20 rpm)

<Solder heat resistance>
The obtained laminated film was conditioned at 25 ° C. and 65% for 24 hours, washed with flux at room temperature, then immersed in a solder bath at 260 ° C. for 30 seconds, and observed for appearance abnormalities such as peeling and swelling.
(Judgment) ○: No appearance abnormality △: Slight appearance abnormality ×: Overall appearance abnormality

<Flexibility>
The obtained laminated film was evaluated according to JIS-K5400. The diameter of the mandrel was 2 mm, and the presence or absence of cracks was confirmed.

<Sleigh>
The obtained laminated film was cut out to 10 cm × 10 cm. A sample conditioned at 25 ° C. and 65% for 24 hours was placed on a horizontal glass plate in a convex state, and the average height of the four corners was evaluated.
(Judgment) ○: Less than 2 mm in height Δ: Less than 10 mm in height ×: More than 10 mm in height

<Adhesion>
According to JIS-K5400, 100 1-mm grids were made on the obtained laminated film, and a peel test was performed using cello tape (registered trademark) to observe the peeled-off state of the grids.
The same process was performed when a polyimide film having a thickness of 25 μm was used as a base material.
(Decision) ○: No peeling at 100/100 Δ: 70 to 99/100
X: 0-70 / 100

<Pencil hardness>
The obtained laminated film was evaluated according to JIS-K5400.

<Light transmittance of film>
The light transmittance in a wavelength region of 400 nm was measured with a spectrophotometer (UV-3150, manufactured by Shimadzu Corporation) (film thickness 20 μm).

<Film mechanical properties>
Using a tensile tester (Orientec RTM-100), a sample cut into a strip shape having a width of 10 mm and a length of 100 mm in the longitudinal direction (MD direction) is sandwiched and fixed by a sample fixing chuck 20 mm above and below, and a tensile speed of 20 mm / And the distance between chucks was 40 mm and the temperature was 25 ° C. and 60 RH%, and the elongation at break and tensile modulus were obtained. In addition, the measurement was performed 5 times and the average value was employ | adopted.

<Film Tg>
Using a dynamic viscoelasticity measuring device (DVA-220 manufactured by IT meter side control), a sample of 4 mm width × 21 mm length was sandwiched between 3 mm each of the sample fixing chuck, the measurement length was 15 mm, the frequency was 110 Hz, and the heating rate was 4 ° C. The maximum point of tan δ when measured under the conditions of / min was defined as the glass transition temperature (Tg).

Production Example 1
Trimellitic anhydride (hereinafter abbreviated as TMA, purity 99.9%, trimellitic acid content 0.1%) in a four-necked 2 liter separable flask equipped with a stirrer, cooling tube, nitrogen inlet tube and thermometer 92.8 g (0.483 mol), 1,4-cyclohexanedicarboxylic acid (hereinafter CHDA); 83.2 g (0.483 mol), polycaprolactone diol (trade name PLACEL, manufactured by Daicel Chemical Industries, Ltd., molecular weight 2000, 168 g (0.084 mol), isophorone diisocyanate (hereinafter IPDI); 222.3 g (1.000 mol), γ-butyrolactone (hereinafter γ-BL); 485.3 g and potassium fluoride as a catalyst (Hereinafter referred to as KF); 1.2 g (2 mol%) was charged, and the temperature was raised to 120 ° C. under a nitrogen stream, The reaction was allowed for 1.5 hours. Subsequently, after heating up to 180 degreeC and making it react for 5 hours, 306.5g of cyclohexanone (henceforth CHX) is added and diluted, and it cools to room temperature, and the pale yellow modified polyimide resin solution A-1 of non-volatile matter 38 mass% Got.

Production Example 2
Pyromellitic anhydride (hereinafter abbreviated as PMDA, purity>99.9%); 114.5 g (0.525 mol) in a four-necked 2 liter separable flask equipped with a stirrer, cooling tube, nitrogen introduction tube and thermometer , CHDA; 72.3 g (0.420 mol), PCL-2000; 210 g (0.105 mol), IPDI; 222.3 g (1.000 mol), γ-BL; 539.9 g and KF as catalyst: 1.2 g ( 2 mol%), and the temperature was raised to 120 ° C. under a nitrogen stream and allowed to react for 1.5 hours. Subsequently, after heating up to 160 degreeC and making it react for 5 hours, 341g of (gamma) -BL was added and diluted, and the light brown modified polyimide resin solution A-2 with a non volatile matter of 38 mass% was obtained by cooling to room temperature.

Production Example 3
In a four-necked 2 liter separable flask equipped with a stirrer, a condenser, a nitrogen inlet tube and a thermometer, TMA: 178.1 g (0.927 mol), PCL-2000; 206 g (0.103 mol), IPDI: 133. 4 g (0.600 mol), 4,4′-dicyclohexylmethane diisocyanate (hereinafter H-MDI); 104.9 g (0.400 mol), γ-BL; 543.2 g and sodium methylate as a catalyst; 1.1 g (2 mol) %), The temperature was raised to 120 ° C. under a nitrogen stream, and the reaction was allowed to proceed for 1.5 hours. Next, after raising the temperature to 180 ° C. and reacting for 5 hours, 343.1 g of CHX was added for dilution, and the mixture was cooled to room temperature to obtain a pale yellow modified polyimide resin solution A-3 having a nonvolatile content of 38% by mass.

Production Example 4
TMA; 98.0 g (0.510 mol), CHDA; 87.8 g (0.510 mol), IPDI; 222. In a four-necked 2 liter separable flask equipped with a stirrer, a condenser, a nitrogen inlet tube and a thermometer. 3 g (1.000 mol), γ-BL; 320.1 g and KF; 1.2 g (2 mol%) as a catalyst were charged, heated to 120 ° C. in a nitrogen stream, and reacted for 1.5 hours. Next, after raising the temperature to 180 ° C. and reacting for 5 hours, 503.0 g of N-methyl-2-pyrrolidone (hereinafter referred to as NMP) was added to dilute, and cooled to room temperature. System resin solution A-4 was obtained.

Production Example 5
In a four-necked 2 liter separable flask equipped with a stirrer, a condenser tube, a nitrogen inlet tube and a thermometer, TMA; 199.8 g (1.040 mol), MDI; 250.3 g (1.000 mol), NMP; 831. 4 g and KF as a catalyst; 1.2 g (2 mol%) were charged, heated to 120 ° C. under a nitrogen stream, and reacted for 2 hours. Next, the temperature was raised to 160 ° C. and reacted for 4 hours, and 129.3 g of NMP was added for dilution, followed by cooling to room temperature to obtain a dark brown polyimide resin solution A-5 having a nonvolatile content of 35% by mass.

Production Example 6
In a four-necked 2 liter separable flask equipped with a stirrer, a condenser tube, a nitrogen inlet tube and a thermometer, TMA; 76.4 g (0.398 mol), ethylene glycol bisanhydro trimellitate (hereinafter referred to as TMEG-200); 163.2 g (0.398 mol), PCL-2000; 448.8 g (0.224 mol), MDI; 250.3 g (1.000 mol), γ-BL; 1305.1 g and KF as catalyst: 1.2 g ( 2 mol%), and the temperature was raised to 120 ° C. under a nitrogen stream and allowed to react for 2 hours. Subsequently, after heating up to 180 degreeC and making it react for 4 hours, 310.7g of (gamma) -BL is added and diluted, The dark brown modified polyimide resin solution A-6 of 35 mass% of non volatile matters is obtained by cooling to room temperature. It was.

Example 1
To 100 parts by mass of the resin content of the modified polyimide resin solution A-1 obtained in Production Example 1, 10 parts by mass of Epicoat 152 (trade name of phenol novolac type epoxy resin manufactured by Yuka Shell Epoxy Co., Ltd.) was added. The modified polyimide resin composition of the present invention was obtained by diluting with cyclohexanone. The resulting modified polyimide resin composition was applied to a glossy surface of an electrolytic copper foil having a thickness of 18 μm so as to have a thickness of 20 μm after drying. After drying with hot air at 80 ° C. for 10 minutes, the laminate film was obtained by heating at 160 ° C. for 120 minutes in an air atmosphere. Moreover, the film was obtained by carrying out the etching removal of the copper foil of the obtained laminated | multilayer film with a ferric chloride solution. The evaluation results are shown in Table 2.

Example 2
To the non-volatile content of 80.5 parts by mass of the modified polyimide resin composition obtained in Example 1, 6.9 parts by mass of Aerogel # 300 (Nippon Aerosil Co., Ltd. hydrophilic silica fine particles) was further added. By adding Floren AC-326 (manufactured by Kyoeisha Chemical Co., Ltd.) as a foaming agent, first kneading roughly, and then repeating kneading three times using a high-speed three roll, the filler is uniformly dispersed and thixotropic properties are obtained. A paste comprising the modified polyimide resin composition of the present invention was obtained. The paste made of the obtained modified polyimide resin composition was applied to the glossy surface of an electrolytic copper foil having a thickness of 18 μm so as to have a thickness of 20 μm after drying. After drying with hot air at 80 ° C. for 10 minutes, the laminate film was obtained by heating at 160 ° C. for 120 minutes in an air atmosphere. Moreover, the film was obtained by carrying out the etching removal of the copper foil of the obtained laminated | multilayer film with a ferric chloride solution. The results are shown in Tables 1 and 2.

Example 3
In Example 2, a paste was prepared in the same manner except that the addition amount of the epoxy resin was changed. The viscosity was adjusted appropriately by adding CHX as a diluent solvent depending on the paste viscosity. The results are shown in Tables 1 and 2.

Examples 4-5
Instead of the modified polyimide resin solution A-1 used in Examples 1 and 2, pastes were prepared in the same manner using A-2 and A-3 with the formulations shown in Table 1. The viscosity was adjusted appropriately by adding CHX as a diluent solvent depending on the paste viscosity. The results are shown in Tables 1 and 2.

Comparative Example 1
In Example 1, evaluation was performed without adding an epoxy resin. The results are shown in Tables 1 and 2. In this case, sufficient solder heat resistance cannot be obtained and the coating film is softened.

Comparative Examples 2-4
Instead of the modified polyimide resin solution used in Examples 1 and 2, pastes were similarly prepared with the formulations shown in Table 1. The viscosity was adjusted appropriately by adding CHX as a diluent solvent depending on the paste viscosity. Further, in Comparative Examples 2 and 4, laminated films were prepared at a drying temperature of 250 ° C. for 60 minutes. The results are shown in Tables 1 and 2. Comparative Example 2 has good transparency, but is a resin that does not contain a flexible component, and therefore has low varnish stability and requires the addition of a nitrogen-based polar solvent. As a result, whitening of the ink occurs and high temperature drying is required. In addition, warping due to a high elastic modulus occurs, and since the elongation at break is small, the flexibility is poor. Comparative Example 3 has a high Tg and excellent heat resistance, but is colored yellow and does not provide transparency. In addition, there are the same problems as in Comparative Example 2. Since Comparative Example 4 contains a flexible component, it dissolves in a non-nitrogen solvent and is excellent in warpage and flexibility, but transparency cannot be obtained.

  The thus obtained modified polyimide resin composition of the present invention and the paste comprising the same are useful as a film forming material for semiconductor elements, overcoat inks for various electronic components, solder resist inks, interlayer insulating films, etc. Since it can be used in a wide range of electronic devices as paints, coating agents, adhesives, etc., it is a big industrial contribution. It is particularly suitable as a transparent film substrate material used for liquid crystal displays and the like.

Claims (5)

As component (A), (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) a polyol represented by the following general formula (1), (c) an alicyclic polyamine A modified polyimide resin obtained by reacting a residue derivative as an essential component in an organic solvent selected from an ether solvent, an ester solvent, a ketone solvent and an aromatic hydrocarbon solvent,
(B) As an ingredient, an epoxy resin having two or more epoxy groups per molecule,
A modified polyimide resin composition characterized in that it contains no organic solvent other than those mentioned above, and does not undergo solvent substitution after the reaction.

[Wherein, m and n are each independently an integer of 1 to 40, and R represents an alkylene group or an arylene group having 1 to 22 carbon atoms]   The film having a thickness of 20 μm obtained by drying and curing the solvent has a light transmittance of 400 nm of 65% or more, a breaking elongation at 25 ° C. of 70% or more, and a tensile elastic modulus of 1.2 GPa or less. The modified polyimide resin composition as described.   Furthermore, the modified polyimide resin composition of Claim 1 which contains an inorganic or organic filler as (C) component, and has thixotropy of 1.3 or more by the variation degree.   A paste comprising the modified polyimide resin composition according to claim 2.   An electronic component having a solder resist layer, a surface protective layer, an interlayer insulating layer, or an adhesive layer obtained by drying and curing the modified polyimide resin composition or paste according to claim 1.