JPWO2011062137A1 - Urethane-modified polyimide flame retardant resin composition - Google Patents

Abstract

Non-nitrogen solvent solubility and varnish stability, low temperature drying / curability, low warpage, flexibility, printability, flame resistance, heat resistance, chemical resistance, electrical properties, workability and economy An excellent urethane-modified polyimide flame retardant resin composition is provided. The urethane-modified polyimide flame retardant resin composition of the present invention comprises (A) (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) a diol compound, and (c) a fat. A urethane-modified polyimide-based resin having a urethane bond produced using an aromatic polyamine residue derivative and / or an aromatic polyamine residue derivative as an essential component, (B) an epoxy resin having two or more epoxy groups per molecule, ( C) an inorganic or organic filler, and (D) a non-halogen flame retardant, wherein (D) the non-halogen flame retardant is a component having a weight loss rate of 50% to 90% at 350 ° C. in an air atmosphere (D -1) and 0% or more and 20% or less of component (D-2) are contained as essential components.

Description

  The present invention relates to a urethane-modified polyimide resin composition having excellent heat resistance and flexibility and suitable for a coating method such as a printing press, a dispenser or a spin coater. The urethane-modified polyimide resin composition of the present invention is useful for a solder resist layer, a surface protective layer, an interlayer insulating layer, or an adhesive layer of a flexible printed wiring board of an electronic component.

  Currently, flexible printed wiring boards are electronic device parts that require flexibility and small space, for example, device mounting boards for display devices such as liquid crystal displays and plasma displays, and boards for mobile phones, digital cameras, portable game machines, etc. Widely used for relay cables, operation switch board, etc.

  By the way, since a solder resist layer, a surface protective layer, an interlayer insulating layer or an adhesive layer, which are constituent elements of a flexible printed wiring board, are often applied and printed in a solution form, as a material thereof, a solvent-soluble ring-closing type A composition comprising a polyimide resin has been proposed.

  However, conventionally, as a solvent for varnishing a polyimide resin, a high-boiling nitrogen polar solvent such as N-methyl-2-pyrrolidone has been used. Therefore, there is a problem that the electronic member is thermally deteriorated. In addition, if the varnish is applied to the substrate and then left for a long period of time, ink, whitening of the coating film and voids may occur due to moisture absorption of the high-boiling nitrogen-based solvent, which makes it difficult to set the working conditions. . Furthermore, since polyimide resins are generally hard with a high elastic modulus, when laminated on a substrate such as a film or a copper foil, warping or the like occurs due to a difference in elastic modulus, which causes a problem in the subsequent process. In addition, the cured film lacks flexibility and has a problem of poor flexibility.

  On the other hand, in many cases, electronic components are required to have flame retardancy. However, heavy metal compounds such as decabrom ether, which has been used as a conventional flame retardant, and heavy metal compounds such as antimony trioxide have been increasingly regulated. ing. Polyimide resin itself has relatively high flame retardancy, but when high flame retardancy such as UL standard is required, phosphorus compounds, nitrogen compounds, hydrated metal compounds (aluminum hydroxide, magnesium hydroxide) ) And other non-halogen flame retardants are used. However, these flame retardants are not sufficiently flame retardant compared to halogen-based ones, and phosphorus-based flame retardants represented by phosphoric acid esters have inferior hydrolysis resistance and heat resistance.

  For example, a polysiloxane-modified polyimide resin has been proposed as a polyimide resin that is soluble in a non-nitrogen solvent and imparts low warpage and flexibility by making the resin flexible and low elastic modulus. (See Patent Documents 1 and 2).

  These polysiloxane-modified polyimide resins use a diamine having an expensive dimethylsiloxane bond as a starting material in order to reduce the elastic modulus, and have a problem inferior in economic efficiency. In addition, as the polysiloxane copolymerization amount increases, there is a problem that adhesion, solvent resistance, and chemical resistance decrease.

  In order to improve these defects, for example, compositions using polycarbonate-modified polyimide resins have been proposed (see Patent Documents 3 to 5).

  These polycarbonate-modified polyimide resins have improved defects derived from polysiloxane and have good printability. However, in the composition obtained from this resin, a polyimide resin polycarbonate is used to reduce warpage. It was necessary to increase the amount of modification, and the heat resistance tended to decrease. Moreover, varnish stability was low and the varnish sometimes solidified within a few days during storage. Furthermore, in general, when a low elastic modulus component is introduced in order to obtain low warpage, the flame retardancy often decreases in contradiction. The coating film obtained from the composition proposed here could not obtain sufficient flame retardancy.

  As a polyimide-based resin composition that is soluble in non-nitrogen solvents, has low warpage and flexibility by making the resin flexible and low elastic modulus, and satisfies the flame retardance standards according to UL standards For example, a composition in which a hydrated metal compound is added to a polycarbonate-modified polyimide resin has been proposed (see Patent Documents 6 to 8).

  These polycarbonate-modified polyimide resin compositions have low warpage, flexibility and flame retardancy, but when introducing a low elastic modulus component to reduce warpage, the heat resistance and flame retardancy are contradictory. Often decreases.

  The proposed composition is intended for tape carrier package (TAB, COF) applications using relatively thick polyimide film substrates, and flexible printed wiring using thin polyimide film substrates of 1 mil (25 μm) or less. For a substrate (FPC) application, sufficient flame retardancy was not obtained. Moreover, when a thin polyimide film base material was used, the low warpage was not sufficient.

  On the other hand, Patent Document 9 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 an isophorone residue. A polyimide resin having an essential component as a component is proposed. Patent Document 10 discloses a polyimide resin containing a polyether as a copolymer component, trimellitic acid as an acid component, and cyclohexanedicarboxylic acid, and a composition comprising the same. Proposed.

  Although these polyimide resins are expected to be excellent in solubility in non-nitrogen solvents, they have not been satisfactory in terms of low warpage, solder heat resistance and printability at the same time as flexible printed wiring board applications. In addition, if any of the polyimide resins is a non-nitrogen reaction solvent, the varnish stability is low, the resin is likely to precipitate over time, and for the purpose of use, it is further re-precipitated to a highly soluble low-boiling solvent. The total replacement of was performed, and it was inferior in economic efficiency. Furthermore, since these proposed compositions mainly consist of alicyclic components, sufficient flame retardancy cannot be obtained.

  Patent Document 11 proposes a composition using a polyimide resin containing a polyalkylene oxide adduct of bisphenol A. Although this polyimide resin composition is excellent in heat resistance, it is not soluble in non-nitrogen solvents, it cannot be said that it has low warpage and flexibility, and flame retardancy was not obtained. .

  Patent Document 12 proposes a polyimide composition in which a hydrated metal compound, a phosphorus compound, or a nitrogen compound as a non-halogen flame retardant is used as a filler in a polysiloxane-modified polyimide resin. This polyimide-based resin composition is expected to satisfy the flame retardance standards according to UL standards in addition to properties such as solder heat resistance and printability for flexible printed circuit board applications. There was a problem due to copolymerization of siloxane compounds. Moreover, like patent documents 7-8, there existed a problem that elastic modulus became high and low curvature property and flexibility fell, when a hydration metal compound with a low flame-retardant effect was contained in large quantities.

  Patent Document 13 proposes a siloxane diamine-modified polyimide resin composition using a special monomer in order to improve the above drawbacks. This polyimide-based resin composition does not contain an inorganic flame retardant, and is expected not to impair the low warpage. However, since an expensive monomer is used, it is inferior in economic efficiency and has adhesiveness caused by a siloxane compound. There was a problem.

  Patent Document 14 proposes a polyurethane resin composition and a polyimide resin composition using a dialkyl phosphinate metal salt as a non-halogen flame retardant. This polyurethane-based resin composition is expected to satisfy the standards of flame retardancy according to UL standards in addition to properties such as solder heat resistance and printability for flexible printed circuit board applications. Since they are not compatible with each other and are blended in a large amount as a filler, flexibility and low warpage are not always sufficient.

  In order to improve these defects, for example, a composition in which a phosphazene that is a non-halogen flame retardant and dissolves in a polyimide resin is blended with a polyimide resin has been proposed (see Patent Documents 15 to 17). These polyimide-based resin compositions are expected to satisfy not only properties such as solder heat resistance and printability, but also flame retardancy and low warpage for flexible printed wiring boards. In order to exhibit a high degree of flame retardancy alone, a large amount of addition is required, and there is a problem that the flame retardant bleeds.

  As described above, in the conventional techniques so far, (1) non-nitrogen solvent solubility and varnish stability, (2) low temperature drying / curing property, (3) low warpage, (4) flexibility, (5 A polyimide-based resin composition applicable as a solder resist layer, a surface protective layer, an interlayer insulating layer or an adhesive layer satisfying simultaneously (i) printability and (6) flame retardancy has not been obtained.

JP 7-304950 A JP-A-8-333455 JP 2001-302895 A JP 2003-138015 A JP 2007-84652 A JP 2008-133418 A JP 2009-96915 A JP 2009-185200 A JP 2003-289594 A JP-A-9-328550 JP 11-293218 A WO 2005-116152 JP 2009-275076 A JP 2007-270137 A JP-A-2005-47995 JP 2002-235001 A JP 2008-297388 A

  The present invention was devised in order to solve the above-mentioned problems of the prior art, and its purpose is (1) non-nitrogen solvent solubility and varnish stability, (2) low temperature drying / curing property, (3) Low warpage, (4) Flexibility, (5) Printability, (6) Excellent flame retardancy, suppresses bleed out of flame retardant, heat resistance, chemical resistance, electrical properties, workability and An object of the present invention is to provide a urethane-modified polyimide-based flame retardant resin composition excellent in economy and an electronic component obtained by using the composition.

（式［Ｉ］及び式［ＩＩ］中、Ｒ^１及びＲ^２は互いに同じであっても異なってもよく、線状又は分岐状のＣ_１〜Ｃ_１０のアルキル及び／又はシクロアルキル及び／又はアリール及び／又はアラルキルであり、Ｒ^１及びＲ^２は互いに結合して隣接するリン原子とともに環を形成しても良い。Ｒ^３は線状又は分岐状のＣ_１〜Ｃ_１０のアルキレン、Ｃ_６〜Ｃ_１０のシクロアルキレン、Ｃ_６〜Ｃ_１０のアリーレン、Ｃ_６〜Ｃ_１０のアルキルアリーレン又はＣ_６〜Ｃ_１０のアリールアルキレンであり、Ｍは、Ｍｇ、Ｃａ、Ａｌ、Ｓｂ、Ｓｎ、Ｇｅ、Ｔｉ、Ｚｎ、Ｆｅ、Ｚｒ、Ｃｅ、Ｂｉ、Ｓｒ、Ｍｎ、Ｌｉ、Ｎａ、Ｋ又はプロトン化した窒素塩基からなる群の少なくとも１種から選択されるカチオンであり、ｍは１〜４の整数であり、ｎは１〜４の整数であり、ｘは１〜４の整数である。）
（７）（Ｄ−２）成分が、２５℃、１０１３．２５ｈＰａの条件下で液体であるフェノキシホスファゼン化合物を含むことを特徴とする（１）から（６）のいずれか一項に記載のウレタン変性ポリイミド系難燃樹脂組成物。
（８）（ｂ）ジオール化合物が、（ｂ−１）ポリオキシアルキレングリコール、及び／又は（ｂ−２）下記一般式［ＩＩＩ］で表されるビスフェノールのポリアルキレンオキサイド付加体を含むことを特徴とする（１）から（７）のいずれか一項に記載のウレタン変性ポリイミド系難燃樹脂組成物。

（式［ＩＩＩ］中、Ｒ_１はＣ_１〜Ｃ_２０のアルキレン基であり、Ｒ_２及びＲ_３は互いに同じであっても異なってもよく、水素またはＣ_１〜Ｃ_４のアルキル基を表し、ｍは１以上の整数であり、ｎは１以上の整数である。）
（９）（Ｅ）硬化促進剤をさらに含有することを特徴とする（１）から（８）のいずれか一項に記載のウレタン変性ポリイミド系難燃樹脂組成物。
（１０）（Ｆ）イオンキャッチャーをさらに含有することを特徴とする（１）から（９）のいずれか一項に記載のウレタン変性ポリイミド系難燃樹脂組成物。
（１１）（Ａ）ウレタン変性ポリイミド系樹脂が、エーテル系溶媒、エステル系溶媒、ケトン系溶媒、及び芳香族炭化水素系溶媒からなる群から選ばれる少なくとも１種の有機溶媒中で反応させて得られるものであることを特徴とする（１）から（１０）のいずれか一項に記載のウレタン変性ポリイミド系難燃樹脂組成物。
（１２）揺変度で１．１以上のチクソトロピー性を有することを特徴とする（１）から（１１）のいずれか一項に記載のウレタン変性ポリイミド系難燃樹脂組成物。
（１３）ソルダーレジスト層、表面保護層、層間絶縁層又は接着剤層を有する電子部品であって、前記層が（１）から（１２）のいずれか一項に記載のウレタン変性ポリイミド系難燃樹脂組成物を乾燥硬化して得られるものであることを特徴とする電子部品。As a result of diligent research to achieve the above object, the present inventors finally completed the present invention. That is, the present invention comprises the following configurations (1) to (12).
(1) (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) a diol compound, and (c) an aliphatic polyamine residue derivative and / or an aromatic polyamine residue derivative A urethane-modified polyimide resin having a urethane bond produced as an essential component,
(B) an epoxy resin having two or more epoxy groups per molecule;
(C) inorganic or organic filler, and (D) non-halogen flame retardant,
A urethane-modified polyimide flame retardant resin composition containing
(D) Two components of a non-halogen flame retardant: a component (D-1) having a weight loss rate of 50% to 90% at 350 ° C. in an air atmosphere and a component (D-2) having a component weight of 0% to 20%. A urethane-modified polyimide-based flame retardant resin composition characterized by comprising
(2) The weight reduction rate of the component (D-1) is 60% or more and 85% or less, and the weight reduction rate of the component (D-2) is 0% or more and 15% or less (1) The urethane-modified polyimide flame retardant resin composition described in 1.
(3) The urethane-modified polyimide system according to (1) or (2), wherein the (D) non-halogen flame retardant contains a phosphorus-based flame retardant that is compatible with the (A) urethane-modified polyimide resin. Flame retardant resin composition.
(4) The component (D-1) contains a 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide derivative, and the component (D-2) contains a phenoxyphosphazene compound (1 ) To (3), a urethane-modified polyimide flame retardant resin composition.
(5) The urethane-modified polyimide flame retardant resin composition according to any one of (1) to (3), wherein the (D) non-halogen flame retardant contains a filler-type non-halogen flame retardant.
(6) The phosphinic acid in which the component (D-1) contains a 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide derivative and the component (D-2) is represented by the following general formula [I] Metal salt, diphosphinic acid metal salt represented by the following general formula [II], reaction product of cyanamide derivative having at least one amino group and phosphoric acid, or cyanamide derivative having at least one amino group and cyanuric acid, The urethane-modified polyimide flame retardant resin composition according to any one of (1) to (3) or (5), which comprises a reaction product of

(In Formula [I] and Formula [II], R ¹ and R ² may be the same or different from each other, and linear or branched C ₁ -C ₁₀ alkyl and / or cycloalkyl and / or Aryl and / or aralkyl, R ¹ and R ² may be bonded to each other to form a ring with an adjacent phosphorus atom, R ³ is a linear or branched C _{1 to} C ₁₀ alkylene, C ₆ arylene _{cycloalkylene,} C 6 _{-C 10} of -C _10, aryl alkylene alkylarylene or _C 6 _{-C 10} in _C 6 _{~C 10,} M is, Mg, Ca, Al, Sb , Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K or a cation selected from at least one of the group consisting of protonated nitrogen bases, m is an integer of 1 to 4 Yes, Is an integer from 1 to 4, x is an integer of 1 to 4.)
(7) The urethane according to any one of (1) to (6), wherein the component (D-2) comprises a phenoxyphosphazene compound that is liquid under conditions of 25 ° C. and 101.25 hPa. Modified polyimide flame retardant resin composition.
(8) The (b) diol compound includes (b-1) polyoxyalkylene glycol and / or (b-2) a polyalkylene oxide adduct of bisphenol represented by the following general formula [III]. The urethane-modified polyimide flame retardant resin composition according to any one of (1) to (7).

(In the formula [III], R ₁ is a C _{1 to} C ₂₀ alkylene group, and R ₂ and R ₃ may be the same or different from each other, and represent hydrogen or a C _{1 to} C ₄ alkyl group. , M is an integer of 1 or more, and n is an integer of 1 or more.)
(9) The urethane-modified polyimide flame retardant resin composition according to any one of (1) to (8), further comprising (E) a curing accelerator.
(10) The urethane-modified polyimide flame retardant resin composition according to any one of (1) to (9), further comprising (F) an ion catcher.
(11) (A) A urethane-modified polyimide resin is obtained by reaction in at least one organic solvent selected from the group consisting of ether solvents, ester solvents, ketone solvents, and aromatic hydrocarbon solvents. The urethane-modified polyimide flame-retardant resin composition according to any one of (1) to (10), wherein
(12) The urethane-modified polyimide flame-retardant resin composition according to any one of (1) to (11), wherein the urethane-modified polyimide flame-retardant resin composition according to any one of (1) to (11) has a thixotropic property of 1.1 or more in terms of degree of change.
(13) An electronic component having a solder resist layer, a surface protective layer, an interlayer insulating layer or an adhesive layer, wherein the layer is the urethane-modified polyimide flame retardant according to any one of (1) to (12) An electronic component obtained by drying and curing a resin composition.

  According to the present invention, (1) non-nitrogen solvent solubility and varnish stability, (2) low temperature drying / curing properties, (3) low warpage, and (4) bending, which have been difficult to satisfy at the same time. (5) Urethane-modified polyimide flame retardant with excellent (5) printability, (6) excellent flame retardancy, suppresses bleed out of flame retardant, and is excellent in heat resistance, chemical resistance, electrical properties, workability and economy A resin composition can be provided. Therefore, the urethane-modified polyimide flame retardant resin composition of the present invention is useful as a film forming material for overcoat inks for various electronic parts such as flexible printed wiring boards, solder resist inks, interlayer insulating films, and paints. It can be used in a wide range of electronic equipment as coating agents, adhesives, etc.

The present invention will be described in detail below.
The urethane-modified polyimide flame retardant resin composition of the present invention is
(A) (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) a diol compound, (c) an aliphatic polyamine residue derivative and / or an aromatic polyamine residue derivative A urethane-modified polyimide resin having a urethane bond produced as an essential component;
(B) an epoxy resin having two or more epoxy groups per molecule;
(C) inorganic or organic filler, and (D) non-halogen flame retardant,
Containing
(D) The non-halogen flame retardant is composed of two components: a component (D-1) having a weight loss of 50% to 90% at 350 ° C. in an air atmosphere and a component (D-2) having a component weight of 0% to 20%. Is contained as an essential component.

  The (a) trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group constituting the component (A) generally reacts with an isocyanate component or an amine component to form a polyimide resin. As the polycarboxylic acid derivative, any of aromatic, aliphatic and alicyclic can be used.

  The copolymerization amount of the component (a) is preferably 30 mol% or more and 90 mol% or less, and 35 mol% or more and 85 mol% or less, in a molar ratio with respect to 100 mol% of all polyamine residue derivatives to be reacted. Is more preferable. If the copolymerization amount is less than the above range, flame retardancy, mechanical properties and heat resistance cannot be obtained. If the copolymerization amount is more than the above range, the component (b) described later cannot be copolymerized in a sufficient amount. And solubility in non-nitrogen solvents may be reduced.

  Examples of aromatic polycarboxylic acid derivatives include trimellitic anhydride, pyromellitic dianhydride, ethylene glycol bisanhydro trimellitate, propylene glycol bisan hydrotrimellitate, 1,4-butanediol bisan. Alkylene glycol bisanhydro trimellitates such as hydrotrimellitate, hexamethylene glycol bisanhydro trimellitate, polyethylene glycol bisan hydrotrimellitate, polypropylene glycol bisan hydrotrimellitate, hydroquinone bisan hydrotrimellitate , Hydroquinone bisethylene oxide adduct dianhydrotrimellitate, 4,4'-biphenylenebisanhydrotrimellitate, 3,3 ', 4,4'-benzophenone tetracarboxylic Dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid Dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylsulfonetetracarboxylic Acid 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- Carboxyphenoxy) phenyl] propane dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis [4- (2,3- or 3,4-dicarboxyphenoxy) phenyl] propane Dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldisiloxane dianhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 2,2-bis (4-hydroxyphenyl) propanedibenzoate-3,3 ', 4,4'-tetracarboxylic dianhydride, 2,3,3 ′, 4-biphenyltetracarboxylic dianhydride and the like.

  Examples of the aliphatic or alicyclic polycarboxylic acid derivatives include butane-1,2,3,4-tetracarboxylic dianhydride and pentane-1,2,4,5-tetracarboxylic dianhydride. , Cyclobutanetetracarboxylic 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 acid bis Anhydride, 1-propyl Hexane-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] dioctane-2,3,5,6-tetracarboxylic acid Anhydride, 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, solubility, cost, etc., polycarboxylic acid derivatives are pyromellitic dianhydride, trimellitic anhydride, ethylene glycol bisanhydro trimellitate, 3, 3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 2,2-bis [4- (2,3- or 3, 4-dicarboxyphenoxy) phenyl] propane dianhydride is preferred, and trimellitic anhydride and ethylene glycol bisanhydro trimellitate are more preferred.

  The (b) diol compound constituting the component (A) is copolymerized as a flexible component that imparts flexibility, low warpage, solubility and the like to the polyimide resin. By copolymerizing the component (b), the elastic modulus of the resin decreases, and the solubility (varnish) stability in the non-nitrogen solvent used as the polymerization solvent increases.

  The amount of copolymerization of component (b) is preferably 10 mol% or more and 70 mol% or less, and 15 mol% or more and 65 mol% or less in terms of a molar ratio to 100 mol% of all polyamine residue derivatives to be reacted. Is more preferable. If the amount of copolymerization is more than the above range, flame retardancy, mechanical properties and heat resistance cannot be obtained, and if it is less than the above range, low warpage and solubility in non-nitrogen solvents may be reduced.

  The molecular weight of the component (b) is preferably a number average molecular weight of 500 or more and 3000 or less, and more preferably 800 or more and 2000 or less. When the molecular weight is less than the above range, the heat resistance, flexibility and low warpage are insufficient, and when it exceeds the above range, the modification reaction does not proceed and the solubility may be lowered.

  Examples of the diol compound include polyalkylene glycol, polyoxyalkylene glycol, polyalkylene oxide adduct of bisphenol, aliphatic / aromatic polyester diols, aliphatic / aromatic polycarbonate diols, polycaprolactone diols, and polybutadiene polyols. , Hydrogenated polybutadiene polyols, hydrogenated polyisoprene polyol, polydimethylsiloxane diol, polymethylphenylsiloxane diol, and the like. Preferred are polyoxyalkylene glycols, polyalkylene oxide adducts of bisphenol, aliphatic / aromatic polyester diols, and aliphatic / aromatic polycarbonate diols, and more preferred are polyoxyalkylene glycols ((b- 1) Component), a polyalkylene oxide adduct of bisphenol represented by the general formula [III] (component (b-2)). Other diol compounds include bisphenols such as bisphenol A and bisphenol F, but these are not preferred because the urethane bond dissociates during heating.

  Aliphatic / aromatic polyester diols include those obtained by dehydration condensation of dicarboxylic acid and diol or transesterification of lower alcohol ester of dicarboxylic acid with diol, and ring-opening polymerization of lactone compounds using diol as an initiator. Or obtained by a condensation reaction between a diol and a hydroxyalkanoic acid.

  Specific examples of the dicarboxylic acid component include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, brassylic acid, tetradecanedioic acid, eicosanedioic acid, and 2-methylsuccinic acid. Acid, 2-methyladipic acid, 3-methyladipic acid, 3-methylpentanedicarboxylic acid, 2-methyloctanedicarboxylic acid, 3,8-dimethyldecanedicarboxylic acid, 3,7-dimethyldecanedicarboxylic acid, dimer acid, water Dimer acids, alkenyl succinic acids such as octenyl succinic acid, dodecenyl succinic acid, octadecenyl succinic acid, aliphatic dicarboxylic acids such as fumaric acid, maleic acid, itaconic acid and their ester-forming derivatives, terephthalic acid, isophthalic acid , Orthophthalic acid, 1,4-naphthalenedicarbo Fatty acids such as acids, aromatic dicarboxylic acids such as 2,6-naphthalenedicarboxylic acid and ester-forming derivatives thereof, 1,4-cyclohexanedicarboxylic acid, tetrahydrophthalic acid, hexahydroisophthalic acid, 1,2-cyclohexene dicarboxylic acid Examples thereof include cyclic dicarboxylic acids and ester-forming derivatives thereof.

  Specific examples of the diol component include ethylene glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, and 1,5-pentane. Diol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, trimethylpentanediol, 2-ethyl-1,3-hexanediol, 1,8-octanediol, 2 -Methyl-1,8-octanediol, 1,9-nonanediol, 2,4-diethyl-1,5-pentanediol, 1,10-decanediol, 2,2-diethyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, diethylene glycol, triethylene glycol Aliphatic diols such as eicosan diol and neopentyl glycol hydroxypivalate, alicyclic diols such as 1,4-cyclohexanedimethanol and tricyclodecane dimethanol, ethylene oxide adducts or propylene oxide addition of bisphenol A or bisphenol S Aromatic ring-containing diols such as products, dimer acid reduced products, and the like.

  Specific examples of the hydroxyalkanoic acid component include 3-hydroxybutanoic acid, 4-hydroxypentanoic acid, and 5-hydroxyhexanoic acid.

  Examples of the lactone include γ-valerolactone, δ-valerolactone, ε-caprolactone, α-methyl-β-propiolactone, β-methyl-β-propiolactone, 3-n-propyl-δ-valerolactone, 6 , 6-dimethyl-δ-valerolactone, glycolide, lactide and the like.

  Aliphatic / aromatic polycarbonate diols obtained by transesterification of diol and carbonate compound, obtained by ring-opening polymerization of cyclic carbonate compound, or obtained by reaction of diol and chloroformate or phosgene It is.

  As the aliphatic / aromatic polycarbonate diols, 50 mol% or more of the alkylene chain contained is preferably an alkylene group having 6 or more carbon atoms, and 90 mol% or more is an alkylene group having 6 or more carbon atoms. Further preferred. Most preferably, it is a polycarbonate diol in which 50 mol% or more of the alkylene chain contained is an alkylene group having 8 or more carbon atoms.

  The aliphatic / aromatic polycarbonate diols are preferably polycarbonate diols having a plurality of types of alkylene groups in the skeleton from the viewpoint of crystallization inhibition and solubility of the resulting urethane-modified polyimide resin. Similarly, a polycarbonate diol having an alkylene group containing a side chain is preferred.

  Examples of (b-1) polyoxyalkylene glycol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly (neopentyl glycol / tetramethylene glycol), and the like.

  The copolymerization amount of the component (b-1) is preferably such that the mass of the polyurethane composed of the component (b-1) and the polyamine residue derivative is 5% by mass or more and 70% by mass or less of the urethane-modified polyimide resin. More preferably, it is 10 mass% or more and 40 mass% or less. If the copolymerization amount is less than the above range, the elastic modulus does not sufficiently decrease, warping occurs when laminated, and solubility in a non-nitrogen solvent decreases. May be deposited. This tendency is particularly remarkable when γ-butyrolactone, glymes, and cyclohexanone that are preferably used in the present invention are used as a solvent. On the other hand, when the above range is exceeded, flame retardancy, mechanical properties, and heat resistance may deteriorate.

  (B-2) The polyalkylene oxide adduct of bisphenol is represented by the following general formula [III], and imparts non-nitrogen solvent solubility and flexibility to the modified polyimide resin. Examples of the polyalkylene oxide include polyethylene oxide, polypropylene oxide, and polytetramethylene oxide. Preferably, those having a number average molecular weight of 200 or more and 2000 or less are used. Specific examples include a polyethylene oxide adduct of bisphenol A and a polypropylene oxide adduct of bisphenol A.

（式［ＩＩＩ］中、Ｒ_１はＣ_１〜Ｃ_２０のアルキレン基、Ｒ_２及びＲ_３は水素または炭Ｃ_１〜Ｃ_４のアルキル基を表し、互いに同じであっても異なってもよく、ｍは１以上の整数であり、ｎは１以上の整数である。）

(In the formula [III], R ₁ represents a C ₁ -C ₂₀ alkylene group, R ₂ and R ₃ represent hydrogen or a carbon C ₁ -C ₄ alkyl group, and may be the same or different from each other; m is an integer of 1 or more, and n is an integer of 1 or more.)

  The copolymerization amount of the component (b-2) is preferably such that the mass of the polyurethane composed of the component (b-2) and the polyamine residue derivative is 10% by mass or more and 75% by mass or less of the urethane-modified polyimide resin. More preferably, it is 20 mass% or more and 70 mass% or less. If the copolymerization amount is less than the above range, the solubility in a non-nitrogen solvent decreases, so that the resin may be precipitated within one month at 5 to 30 ° C. This tendency is particularly remarkable when γ-butyrolactone, glymes, and cyclohexanone that are preferably used in the present invention are used as a solvent. On the other hand, when the above range is exceeded, flame retardancy, mechanical properties, and heat resistance may deteriorate.

  As the (c) aliphatic polyamine residue derivative constituting the component (A), aliphatic polyisocyanate and aliphatic polyamine are used. Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate. Hexamethylene diisocyanate is preferred. Examples of the aliphatic polyamine include hexamethylene diamine, 2,2,4-trimethylhexamethylene diamine, and lysine diamine. Hexamethylenediamine is preferred.

  As the (c) aromatic polyamine residue derivative constituting the component (A), aromatic polyisocyanate and aromatic polyamine are used. Aromatic polyisocyanates include, 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 2,2'- 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, diphenyl ether-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'-Diethoxybi Eniru-4,4'-diisocyanate, and the like. In view of heat resistance, adhesion, solubility, cost, etc., aromatic polyisocyanates are diphenylmethane-4,4′-diisocyanate, tolylene-2,4-diisocyanate, m-xylylene diisocyanate, 3,3 ′. Alternatively, 2,2′-dimethylbiphenyl-4,4′-diisocyanate is preferable, and diphenylmethane-4,4′-diisocyanate and tolylene-2,4-diisocyanate are more preferable.

  Examples of aromatic polyamines include diphenylmethane-2,4'-diamine, 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'-diamine, 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'-diamine, 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'-diamine, diphenylmethane-4,4'-diamine, diphenylmethane-3 , 3'-diamine, diphenylmethane-3,4'-diamine, diphenyl ether -4,4'-diamine, benzophenone-4,4'-diamine, diphenylsulfone-4,4'-diamine, tolylene-2,4-diamine, tolylene-2,6-diamine, m-xylylenediamine, p Xylylenediamine, naphthalene-2,6-diamine, 4,4 '-[2,2bis (4-phenoxyphenyl) propane] diamine, 3,3' or 2,2'-dimethylbiphenyl-4,4 ' -Diamine, 3,3'- or 2,2'-diethylbiphenyl-4,4'-diamine, 3,3'-dimethoxybiphenyl-4,4'-diamine, 3,3'-diethoxybiphenyl-4, 4'-diamine etc. are mentioned. In view of heat resistance, adhesion, solubility, cost, etc., the aromatic polyamine is diphenylmethane-4,4′-diamine, tolylene-2,4-diamine, m-xylylenediamine, 3,3 ′ or 2,2'-dimethylbiphenyl-4,4'-diamine is preferred, and diphenylmethane-4,4'-diamine and tolylene-2,4-diamine are more preferred.

  (C) The aliphatic polyamine residue derivative and / or the aromatic polyamine residue derivative may be used alone or in combination of two or more. The ratio of the aliphatic polyamine residue derivative and / or the aromatic polyamine residue derivative is not particularly limited, and is appropriately set within the range where the solubility and low warpage are not impaired in consideration of the amount of the diol compound (b). I do not care.

  (A) In the urethane-modified polyimide resin, in addition to the aliphatic polyamine residue derivative and the aromatic polyamine residue derivative, the alicyclic may be further added as necessary as long as the low warpage, heat resistance, and flame retardancy are not impaired. A group polyamine residue derivative may be copolymerized. Specifically, as the alicyclic polyamine residue derivative, for example, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, transcyclohexane-1,4-diisocyanate, hydrogenated m-xylylene diisocyanate, norbornylene diisocyanate And alicyclic polyisocyanates such as In view of heat resistance, adhesion, solubility, cost, etc., isophorone diisocyanate and 4,4′-dicyclohexylmethane diisocyanate are preferable.

  Furthermore, trifunctional or higher functional polyamine residue derivatives may be used, and those stabilized with a blocking agent necessary to avoid changes over time may be used. When the trifunctional or higher functional polyamine residue derivative is a trifunctional or higher functional polyisocyanate, examples of the blocking agent include alcohol, phenol, and oxime, but there is no particular limitation. These trifunctional or higher functional 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.

  In the component (A), aliphatic, alicyclic, and aromatic dicarboxylic 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, Maleic acid, dimer acid, hydrogenated dimer acid and the like can be mentioned. Examples of the alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4, 4'-dicyclohexyldicarboxylic acid and the like, and as aromatic dicarboxylic acid, Example, if isophthalic acid, terephthalic 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. In view of heat resistance, adhesion, solubility, cost, etc., the dicarboxylic acids are preferably sebacic acid, 1,4-cyclohexanedicarboxylic acid, dimer acid, and isophthalic acid.

  (A) A urethane-modified polyimide resin is a method of producing by decarboxylation from a polycarboxylic acid component having an acid anhydride group and an isocyanate component (isocyanate method), or reacting a polycarboxylic acid component having an acid anhydride group with an amine. It is produced by a known method such as a method (direct method) of ring-closing after making it into an amic acid. Industrially, an isocyanate method capable of urethane modification is advantageous.

  (A) In the case of producing a urethane-modified polyimide resin by an isocyanate method, (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group as a component and a diol compound as a component (b) The amount is preferably such that the number of isocyanate groups / (number of acid anhydride groups + number of carboxylic acid groups + number of hydroxyl groups) = 0.80 to 1.20. If it is out of the above range, it will be difficult to increase the molecular weight of the urethane-modified polyimide resin, heat resistance and flexibility may be lowered, and the coating film may be brittle.

  (A) The polymerization reaction of the urethane-modified polyimide resin is preferably carried out in the presence of at least one organic solvent selected from ether solvents, ester solvents, ketone solvents, and aromatic hydrocarbon solvents, for example, isocyanate. In the method, carbon dioxide gas that is liberated and generated is removed from the reaction system by heat condensation.

  Examples of ether solvents include glymes 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 the solvent include γ-butyrolactone, propylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate (butyl cellosolve acetate), ethylene glycol monoethyl ether acetate, ethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate (ethyl carbitol acetate). ), Diethylene glycol mono Examples include ketyl acetate, 3-methoxybutyl acetate, dipropylene glycol methyl ether acetate, propylene glycol diacetate, methyl benzoate, and ethyl benzoate. Examples of ketone solvents include methyl isobutyl ketone, cyclopentanone, cyclohexanone, Examples of the aromatic hydrocarbon solvent include toluene, xylene, and solvesso. These may be used alone or in combination of two or more.

  (A) In order to produce a varnish of a urethane-modified polyimide resin, it is preferable to select and use a solvent that dissolves the urethane-modified polyimide resin to be produced so that the varnish can be used as it is after polymerization. In this case, complicated operations such as solvent replacement are eliminated, and it becomes possible to manufacture at low cost. The boiling point of the solvent is preferably 140 ° C. or higher and 230 ° C. or lower. If the temperature is lower than 140 ° C., the solvent may be volatilized during the polymerization reaction. For example, when screen printing is performed, the solvent may volatilize quickly and the plate may be clogged. When it exceeds 230 ° C., it becomes difficult to impart low temperature drying / curing properties. In order to carry out the reaction in a homogeneous system with relatively high volatility, low temperature drying / curing property, excellent varnish stability and efficient, γ-butyrolactone, cyclohexanone, diglyme, triglyme, ethyl carbitol Acetate is preferred.

  The amount of the solvent used is preferably 0.8 to 5.0 times (mass ratio) of the urethane-modified polyimide resin to be generated, and more preferably 0.9 to 2.0 times. If the amount used is less than the above range, the viscosity at the time of synthesis is too high, and the synthesis tends to be difficult due to the inability to stir.

  (A) As a manufacturing method of a urethane-modified polyimide resin, in the case of the isocyanate method, for example, (1) (a) component, (b) component, and (c) component are used at once and reacted together. , A method for obtaining a urethane-modified polyimide resin, (2) (a) component and / or (b) component and an excess amount of (c) component were reacted to synthesize a urethane-modified oligomer having an isocyanate group at the terminal. Then, (a) component and / or (b) component is added and reacted to obtain a urethane-modified polyimide resin, (3) excess (a) component and / or (b) component, and (c) ) After reacting the component to synthesize a urethane-modified oligomer having a carboxylic acid group and / or an acid anhydride group and / or a hydroxyl group at the terminal, the component (c) is added and reacted to obtain a urethane-modified polyimide resin. Direction And the like.

  In the case of the isocyanate method, the reaction temperature is preferably 60 to 200 ° C, more preferably 100 to 180 ° C. When the reaction temperature is less than the above range, the reaction time becomes too long, and when it exceeds the above range, the monomer component may be decomposed during the reaction. In addition, a three-dimensional reaction occurs and gelation is likely to occur. The reaction temperature may be performed in multiple stages. The reaction time can be appropriately selected depending on the scale of the batch, the reaction conditions employed, particularly the reaction concentration.

  In the case of the isocyanate method, triethylamine, lutidine, picoline, undecene, triethylenediamine (1,4-diazabicyclo [2.2.2] octane), DBU (1,8-diazabicyclo [5.4.0] are used to accelerate the reaction. ] -7-undecene) and the like, lithium methylate, sodium methylate, sodium ethylate, alkali metal such as potassium butoxide, potassium fluoride, sodium fluoride, alkaline earth metal compound or titanium, cobalt, You may carry out in presence of catalysts, such as metals, such as tin, zinc, and aluminum, and a metalloid compound.

  (A) The logarithmic viscosity of the urethane-modified polyimide resin 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 less than the above range, 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, if it is larger than the above range, it will be difficult to dissolve in the solvent and it will be insoluble during the polymerization. Moreover, the viscosity of a varnish becomes high and handling becomes difficult or adhesiveness with a base material falls. Furthermore, the nonvolatile content concentration of the paste cannot be increased, and it becomes difficult to form a thick film. By appropriately adjusting the polymerization conditions such as the monomer ratio and the polymerization temperature, a urethane-modified polyimide resin having a logarithmic viscosity in this range can be obtained.

  (A) The glass transition temperature of the urethane-modified polyimide resin is preferably 20 ° C. or higher, more preferably 60 ° C. or higher. If it is less than the said temperature, heat resistance may run short and there exists a possibility that resin may block. Although an upper limit is not specifically limited, 300 degrees C or less is preferable from a solvent solubility viewpoint. By appropriately adjusting the polymerization conditions such as the monomer ratio, a urethane-modified polyimide resin having a glass transition temperature in this range can be obtained.

  The urethane-modified polyimide-based flame retardant resin composition of the present invention is (B) by curing two or more urethane-modified polyimide-based resins for the purpose of improving film properties after film formation. An epoxy resin having an epoxy group is contained.

  Examples of the component (B) epoxy resin include bisphenol A type epoxy resins, hydrogenated bisphenol A type epoxy resins, bisphenol F type epoxy resins, brominated bisphenol A type epoxy resins, phenol novolac type epoxy resins, and o-cresol novolac. Type epoxy resin, flexible epoxy resin, epoxidized polybutadiene, polyfunctional epoxy resin, amine type epoxy resin, heterocycle-containing epoxy resin, alicyclic epoxy resin, bisphenol S type epoxy resin, triglycidyl isocyanurate, bixylenol type An epoxy resin, a bisphenol-type epoxy resin, a naphthalene-type epoxy resin, a dicyclopentadiene-type epoxy resin, a phosphorus-containing epoxy resin, and the like may be mentioned, and these may be used alone or in combination of two or more.

  Among these epoxy resins, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin having more than two epoxy groups in one molecule, o-cresol novolac type epoxy resin, amine type epoxy resin are It is a non-halogen type, and is preferred in terms of compatibility with the urethane-modified polyimide resin of component (A), solvent resistance, chemical resistance, and moisture resistance.

  (B) As for the usage-amount of an epoxy resin, 1-50 mass parts is preferable with respect to 100 mass parts of urethane-modified polyimide resin, 2-40 mass parts is still more preferable, and 3-30 mass parts is especially preferable. If the amount of the epoxy resin is less than the above range, solder heat resistance, solvent resistance, chemical resistance, and moisture resistance tend to decrease. If the amount exceeds the above range, low warpage, mechanical properties, heat resistance, varnish stability And compatibility with urethane-modified polyimide resin tends to decrease.

  The total usage amount of the component (B) added to the component (A) is preferably 40 to 90% by mass when the entire nonvolatile content of the urethane-modified polyimide resin composition is 100% by mass. More preferably, it is 45-80 mass%.

  (B) The epoxy resin may further contain an epoxy compound having only one epoxy group in one molecule as a diluent.

  (B) 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 that contained in the urethane-modified polyimide resin, or directly to the urethane-modified polyimide resin. It may be added.

  In the present invention, in addition to the epoxy resin, a known and commonly used curing system such as polyisocyanate, cyanate ester, oxetane, and acrylate may be used in combination.

  The urethane-modified polyimide flame retardant resin composition of the present invention contains (C) an inorganic or organic filler in order to improve the workability during coating and printing and the film properties after film formation.

(C) The inorganic or organic filler is not particularly limited as long as it can be dispersed in the urethane-modified polyimide resin and can impart thixotropic properties. 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 ), barium oxalate (BaO · 8SiO 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) and the like can be used, and these may be used alone or in combination of two or more. From the viewpoint of imparting the color tone, transparency, mechanical properties, and thixotropy of the obtained paste, silica fine particles are preferred.

  As the inorganic filler, those having an average particle size of 50 μm or less and a maximum particle size of 100 μm or less are preferable, an average particle size of 20 μm or less is more preferable, and an average particle size of 10 μm or less is most preferable. The average particle diameter (median diameter) referred to here is determined on a volume basis using a laser diffraction / scattering particle size distribution measuring apparatus. When the average particle diameter exceeds 50 μm, it becomes difficult to obtain a composition having sufficient thixotropy, and the flexibility of the resulting coating film decreases. When the maximum particle diameter exceeds 100 μm, the appearance and adhesion of the coating film tend to be insufficient.

  Any organic filler may be used as long as it can be dispersed in the above-described urethane-modified polyimide resin solution to impart thixotropic properties, and examples thereof include polyimide resin particles, benzoguanamine resin particles, and epoxy resin particles.

  (C) The amount of the inorganic or organic filler used is preferably 0.5 to 25% by mass when the entire nonvolatile content of the urethane-modified polyimide resin composition 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 0.5% by mass, the printability tends to be lowered, and if it exceeds 25% by mass, the mechanical properties such as the flexibility of the coating film and the transparency tend to be lowered. .

  Since the urethane-modified polyimide flame retardant resin composition of the present invention has flame retardancy, it contains (D) a non-halogen flame retardant. (D) The non-halogen flame retardant is composed of two components: a component (D-1) having a weight loss rate of 50% or more and 90% or less at 350 ° C. in an air atmosphere and a component (D-2) having a proportion of 0% or more and 20% or less. Is contained as an essential component. The weight reduction rate of the component (D-1) is preferably 60% to 85%, and the weight reduction rate of the component (D-2) is preferably 0% to 15%.

  Specifically, the weight reduction rate is determined by heating from room temperature to 100 ° C. at a heating rate of 10 ° C./min and holding for 30 minutes in an air atmosphere by TGA (thermogravimetric analysis), and then at a heating rate of 10 ° C. / The weight reduction rate from 150 ° C. to 350 ° C. when heated on an aluminum pan to 600 ° C. per minute. Thus, by blending a flame retardant having a large weight reduction rate and a flame retardant having a small weight reduction rate as a non-halogen flame retardant, high flame retardancy can be achieved with an extremely small addition amount. The reason for this is that a flame retardant with a weight reduction rate higher than that of urethane-modified polyimide resin volatilizes to create a nonflammable atmosphere, and forms char on the surface to suppress the generation of resin decomposition gas, and the weight reduction rate is low. This is presumably because the reaction between the flame retardant and the resin and the formation of the surface heat insulating structure are combined to obtain an efficient flame retardancy. And as a result, the influence which a flame retardant has on other characteristics, such as the heat resistance of a coating film consisting of a urethane-modified polyimide-type flame retardant resin composition, flexibility, and bleed out (juicing), can be suppressed.

  Although it does not specifically limit as such (D) non-halogen flame retardant, It is preferable to contain the phosphorus flame retardant which is compatible with (A) urethane-modified polyimide resin. By acting as a plasticizer for the urethane-modified polyimide resin, the low warpage of the coating film can be improved.

  In the present invention, the phosphorus-based flame retardant that is compatible with the urethane-modified polyimide resin is, for example, a lower Tg of the blended composition than the Tg (glass transition temperature) of the urethane-modified polyimide meter resin alone. The behavior can be grasped by, for example, the change of the calorimetric displacement position of DSC (Differential Scanning Calorimetry) and the peak position of the loss tangent in DMA (Dynamic Viscoelasticity Measurement).

  Furthermore, as such (D) non-halogen flame retardant, it is preferable to include a urethane-modified polyimide resin and a filler-type non-halogen flame retardant that is incompatible with the solvent. By blending a filler-type flame retardant, the heat resistance of the coating film, particularly physical heat resistance such as blocking during heating, and the bleed-out of the flame retardant can be improved.

  Examples of the filler-type non-halogen flame retardant include a phosphinic acid metal salt represented by the following general formula [I], a diphosphinic acid metal salt represented by the following general formula [II], and a cyanamide derivative having at least one amino group. And a reaction product of a cyanamide derivative having at least one amino group and cyanuric acid.

（式［Ｉ］及び式［ＩＩ］中、Ｒ^１及びＲ^２は互いに同じであっても異なってもよく、線状又は分岐状のＣ_１〜Ｃ_１０のアルキル及び／又はシクロアルキル及び／又はアリール及び／又はアラルキルであり、Ｒ^１及びＲ^２は互いに結合して隣接するリン原子とともに環を形成しても良い。Ｒ^３は線状又は分岐状のＣ_１〜Ｃ_１０のアルキレン、Ｃ_６〜Ｃ_１０のシクロアルキレン、Ｃ_６〜Ｃ_１０のアリーレン、Ｃ_６〜Ｃ_１０のアルキルアリーレン又はＣ_６〜Ｃ_１０のアリールアルキレンであり、Ｍは、Ｍｇ、Ｃａ、Ａｌ、Ｓｂ、Ｓｎ、Ｇｅ、Ｔｉ、Ｚｎ、Ｆｅ、Ｚｒ、Ｃｅ、Ｂｉ、Ｓｒ、Ｍｎ、Ｌｉ、Ｎａ、Ｋ又はプロトン化した窒素塩基からなる群の少なくとも１種から選択されるカチオンであり、ｍは１〜４の整数であり、ｎは１〜４の整数であり、ｘは１〜４の整数である。）In addition, (D) the non-halogen flame retardant is 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide from the viewpoint of flame retardancy, hydrolysis resistance, heat resistance and surface bleed out suppression. Derivatives, phenoxyphosphazene compounds, phosphinic acid metal salts represented by the following general formula [I], diphosphinic acid metal salts represented by the following general formula [II], cyanamide derivatives having at least one amino group and phosphoric acids The reaction product is preferably a reaction product of a cyanamide derivative having at least one amino group and cyanuric acid, and the component (D-1) is a 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide derivative. (D-2) component is a phenoxyphosphazene compound, a phosphinic acid metal salt represented by the following general formula [I], A diphosphinic acid metal salt represented by [II], a reaction product of a cyanamide derivative having at least one amino group and phosphoric acid, a reaction product of a cyanamide derivative having at least one amino group and cyanuric acid Is more preferable.

(In Formula [I] and Formula [II], R ¹ and R ² may be the same or different from each other, and linear or branched C ₁ -C ₁₀ alkyl and / or cycloalkyl and / or Aryl and / or aralkyl, R ¹ and R ² may be bonded to each other to form a ring with an adjacent phosphorus atom, R ³ is a linear or branched C _{1 to} C ₁₀ alkylene, C ₆ arylene _{cycloalkylene,} C 6 _{-C 10} of -C _10, aryl alkylene alkylarylene or _C 6 _{-C 10} in _C 6 _{~C 10,} M is, Mg, Ca, Al, Sb , Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K or a cation selected from at least one of the group consisting of protonated nitrogen bases, m is an integer of 1 to 4 Yes, Is an integer from 1 to 4, x is an integer of 1 to 4.)

  As the 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide derivative, for example, HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) from Sanko Co., Ltd., HCA-HQ (10- (2,5-dihydroxyphenyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), SANKO-BCA (10-benzyl-9,10-dihydro-) 9-oxa-10-phosphaphenanthrene-10-oxide), 10- (2,5-dihydroxy-6-methylphenyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (2,5-dihydroxy-2-naphthyl) -9,10-dihydro-9-oxa-10-phosphafe Trento-10-oxide, 2- (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-10-yl) methylsuccinic acid bis (2-hydroxyethyl) ester, 10-methyl-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-phenyl-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, ethyl (3- (9,10 -Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-10-yl) methyl) -2,5-pyrrolidinedione and the like.

  Of these 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide derivatives, those compatible with (A) urethane-modified polyimide resins are preferred, and SANKO-BCA (10-benzyl-9,10 -Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is more preferred. HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), HCA-HQ (10- (2,5-dihydroxyphenyl) -9,10-dihydro-9-oxa-10- Phosphaphenanthrene-10-oxide) has reactivity with epoxy resins, but tends to bleed on the surface, to be incompatible with urethane-modified polyimide resins, and insoluble in non-nitrogen solvents. For this reason, it is appropriately selected in consideration of performance such as low warpage.

  Examples of the phenoxyphosphazene compound include cyclic phenoxyphosphazenes such as trade names SPE-100 and SPB-100L manufactured by Otsuka Chemical Co., Ltd., and cyclic cyanophenoxyphosphazenes such as trade names FP-300 manufactured by Fushimi Pharmaceutical Co., Ltd. Cyclic hydroxyphenoxyphosphazenes such as trade name SPH-100 manufactured by Otsuka Chemical Co., Ltd., chain phenoxyphosphazenes, cross-linked phenoxyphosphazenes, and the like can be mentioned. Since chain phosphazenes have substituents at the molecular ends, they are generally cyclic. The phosphorus content is reduced compared to phosphazene. Accordingly, in the present invention, cyclic phosphazenes are preferable, and cyclic trimers and / or tetrameric phosphazenes are more preferable. When a reactive phosphazene having a functional group that reacts with a urethane-modified polyimide resin such as SPH-100 is used, it is incorporated into a curing system, and therefore, it does not cause bleeding on the surface, which is preferable.

  In addition, when using non-reactive phosphazene that does not have a functional group that reacts with urethane-modified polyimide resin, the crystalline one may bleed on the surface over time or may be affected by hydrolysis under severe conditions. Phosphazene, which is a liquid under conditions of 25 ° C. and 1013.25 hPa, such as SPB-100L, is preferably used, because free phosphorus may be eluted in response to the degradation and the insulating properties may be degraded by decomposition products. Is preferred.

  Examples of phosphinic acid metal salts include Al dimethylphosphinic acid Al, methylethylphosphinic acid Al, diethylphosphinic acid Al, and other dialkylphosphinic acid Al salts, phenylphosphinic acid Al, diphenylphosphinic acid Al, and other arylphosphinic acid Al salts, methyl Alkyl aryl phosphinic acid Al salt such as phenylphosphinic acid Al, 1-hydroxy-1H-phosphorane-1-oxide Al salt, 2-carboxy-1-hydroxy-1H-phosphorane-1-oxide Al salt Examples include Al salts of alkylenephosphinic acid that may be used, Zn salts corresponding to these Al salts, Ca salts, and other metals.

  Specific examples of the diphosphinic acid salt include alkane bis (phosphinic acid) Al salt such as ethane-1,2-bis (phosphinic acid) Al salt, ethane-1,2-bis (methylphosphinic acid) Al salt, and the like. Examples include alkanebis (alkylphosphinic acid) Al salts, Zn salts corresponding to these Al salts, Ca salts, and other metal salts.

That is, in the general formula [I] and the general formula [II], R ¹ and R ² may be the same or different, and may be a linear or branched C _{1 to} C ₁₀ alkyl group and And / or a cycloalkyl group and / or an aryl group and / or an aralkyl group, particularly preferably the same or different, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group. , Tert-butyl group, n-pentyl group or phenyl group.

The ring formed by combining R ¹ and R ² together with the adjacent phosphorus atom is a heterocycle having the phosphorus atom as a hetero atom constituting the ring, and is usually a 4-20 membered heterocycle, preferably a 5-16 member. A heterocycle is mentioned. The heterocyclic ring having a phosphorus atom may be a bicyclo ring or may have a substituent.

R ³ is a linear or branched C _{1 to} C ₁₀ alkylene group, a C _{6 to} C ₁₀ cycloalkylene group, a C _{6 to} C ₁₀ arylene group, a C _{6 to} C ₁₀ alkylarylene group, or a C _6. To C ₁₀ arylalkylene group, and preferably alkylene group is methylene group, ethylene group, n-propylene group, isopropylene group, n-butylene group, tert-butylene group, n-pentylene group, n-octylene. Group, n-dodecylene group, cycloalkylene group, cyclohexylene group, cyclohexadimethylene group, arylene group, phenylene group or naphthylene group, alkylarylene group, methylphenylene group, ethylphenylene group, tert- Butylphenylene group, methylnaphthylene group, ethylnaphthylene group, or ter Examples of the t-butylnaphthylene group and arylalkylene group include a phenylmethylene group, a phenylethylene group, a phenylpropylene group, and a phenylbutylene group.

  M is at least one selected from the group consisting of Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K, or a protonated nitrogen base. Cations selected, preferably Mg, Ca, Al, Ti, Zn ions.

  The phosphinic acid salt and the diphosphinic acid salt include a polymer or a condensate of these phosphinic acid polyvalent salts and / or diphosphinic acid polyvalent salts.

  The average particle size of the phosphinates is preferably 10 μm or less, more preferably 8 μm or less, and even more preferably 5 μm or less. When the average particle diameter exceeds 10 μm, the amount used for developing sufficient flame retardancy increases, which is economically disadvantageous. In addition, insulation reliability, flexibility, adhesion, appearance and the like are deteriorated. Specific examples of such preferred phosphinic acid salts include aluminum diethylphosphinate, which is commercially available from Clariant Japan Co., Ltd. under the trade names Exolite OP935 and OP930.

  The average particle diameter (median diameter) of the phosphinates can be determined on a volume basis using a laser diffraction / scattering particle size distribution analyzer.

A reaction product of a cyanamide derivative having at least one amino group and phosphoric acid, a reaction product of a cyanamide derivative having at least one amino group and cyanuric acid, and a cyanamide derivative having at least one amino group are amino And a group having a unit represented by —N═C═N— or —N═C (—N <) ₂ , and amino group-containing triazines (melamine, melam, melem, melon, guanamine, acetoguanamine, Amino group-containing 1,3,5-triazines such as benzoguanamine, amino group-containing 1,2,4-triazines such as 3-amino-1,2,4-triazine), amino group-containing triazoles (2, Cycyanamides such as amino group-containing 1,3,4-triazoles such as 5-diamino-1,3,4-triazole) And acyclic cyanamide derivatives such as derivatives and guanidines (guanidine, guanidine derivatives (dicyandiamide, guanylurea, etc.)), and the like. Preferred cyanamide derivatives are amino group-containing 1,3,5-triazines, guanidine or derivatives thereof, in particular melamine or melamine condensation products. These may be used alone or in combination of two or more.

  The phosphoric acid to be reacted with the cyanamide derivative is non-condensed phosphoric acid (orthophosphoric acid, metaphosphoric acid, phosphorous acid (phosphonic acid), hypophosphorous acid (phosphinic acid), etc.), inorganic phosphoric acid such as polyphosphoric acid. . Polyphosphoric acid includes condensed phosphoric acids such as pyrophosphoric acid, triphosphoric acid, and tetraphosphoric acid.

  Preferred as a reaction product of a cyanamide derivative having at least one amino group and phosphoric acid, and as a reaction product of a cyanamide derivative having at least one amino group and cyanuric acid is a condensation product of melamine, melamine or melamine Containing at least one of a condensation product and phosphoric acid reaction product, a melamine or melamine condensation product and phosphoric acid condensate reaction product, and a melamine or melamine condensation product and cyanuric acid reaction product More preferred are melamine polyphosphate, melem polyphosphate, melam polyphosphate, dimelamine pyrophosphate, melamine cyanurate, and most preferred is a longer condensation degree of 2 or more, especially 10 or more and 50 or less. Melamine polyphosphates and melamine shear with chain length Is the rate. These may be used alone or in combination of two or more.

  The average particle size of the reaction product of the cyanamide derivative having at least one amino group and phosphoric acid, the reaction product of the cyanamide derivative having at least one amino group and cyanuric acid is preferably 10 μm or less, and more preferably Is 8 μm or less, more preferably 5 μm or less. When the average particle diameter exceeds 10 μm, the amount used for developing sufficient flame retardancy increases, which is economically disadvantageous. In addition, insulation reliability, flexibility, adhesion, appearance, and the like are deteriorated. Specific examples of such a reaction product of a cyanamide derivative having at least one amino group and phosphoric acid and a reaction product of a cyanamide derivative having at least one amino group and cyanuric acid include, for example, Ciba Specialty Trade names MELAPURE 200, MC25 manufactured by Tea Chemical Co., Ltd., trade names PHOSMEL-200 manufactured by Nissan Chemical Industries, Ltd., trade names MPP-A manufactured by Sanwa Chemical Co., Ltd., trade names STIBACE MC-5F, MC-5S, MC manufactured by Sakai Chemical Industries, Ltd. -2010N etc. are mentioned.

  The phosphorus content in the urethane-modified polyimide flame retardant resin composition of the present invention is preferably 1.4 to 7.0% by mass, and the addition amount of the component (D) is adjusted so as to fall within this range. Preferably they are 1.6 mass% or more and 4.8 mass% or less, More preferably, they are 2.0 mass% or more and 4.0 mass% or less. If the phosphorus content is less than the above range, good flame retardancy cannot be obtained, and if it exceeds the above range, the mechanical properties, heat resistance, adhesion and insulation properties of the coating film may be lowered.

  The blending ratio of the component (D-1) and the component (D-2) is not particularly limited as long as the phosphorus content in the urethane-modified polyimide flame retardant resin composition and the required flame retardancy can be achieved. It is preferable to use in the range of (D-1) :( D-2) = 80: 20 to 40:60 by mass ratio. When the component (D-1) exceeds 80% by mass of the total component (D), the heat resistance of the coating film is liable to be impaired. When the component is less than 40% by mass, low warpage cannot be obtained, and (D-2) When phenoxyphosphazene is used as a component, there is a concern that bleeding out may occur.

  In the present invention, for the purpose of further improving the flame retardancy, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, triethyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, cresyl bis (2,6-xylenyl) ) Phosphate, 2-ethylhexyl phosphate, dimethyl methyl phosphate, resorcinol bis (diphenol A bis (dicresyl) phosphate, diethyl-N, N-bis (2-hydroxyethyl) aminomethyl phosphate, diethyl phosphinate, phenyl phosphinate, diphenyl Phosphinic flame retardants such as phosphinate, organic phosphine oxide, phosphoric acid amide, red phosphorus, ammonium polyphosphate, triazine, succinoguanamine, triguana , Melem, melam, tris (β-cyanoethyl) isocyanurate, acetoguanamine, guanylmelamine sulfate, melem sulfate, melam sulfate, nitrogen flame retardant, potassium diphenylsulfone-3-sulfonate, aromatic sulfonimide metal salt, Metal salt flame retardants such as alkali metal salts of polystyrene sulfonate, hydrated metal flame retardants such as aluminum hydroxide, magnesium hydroxide, dolomite, hydrotalcite, barium hydroxide, basic magnesium carbonate, zirconium hydroxide, tin oxide Flame retardant, silica, aluminum oxide, iron oxide, titanium oxide, manganese oxide, magnesium oxide, zirconium oxide, zinc oxide, molybdenum oxide, cobalt oxide, bismuth oxide, chromium oxide, tin oxide, antimony oxide, nickel oxide, copper oxide, oxidation Tungsten, ho Zinc acid, zinc metaborate, barium metaborate, zinc carbonate, magnesium carbonate, calcium carbonate, barium carbonate, zinc stannate and other inorganic flame retardants / flame retardants, silicone powder and other flame retardants / flame retardant aids, etc. Non-halogen flame retardants may be used in combination, or these may be used alone or in combination of two or more. You may set suitably in the range by which various physical properties, such as the electrical property of a film | membrane, heat resistance, and environmental suitability, are not impaired.

  The urethane-modified polyimide flame retardant resin composition of the present invention may further contain (E) a curing accelerator in order to further improve properties such as adhesion, chemical resistance, and heat resistance.

  The (E) curing accelerator is not particularly limited as long as it can accelerate the curing reaction between the urethane-modified polyimide resin, the epoxy resin, and the non-halogen flame retardant.

  (E) Specific examples of the epoxy resin curing agent include, for example, guanamines such as imidazole derivatives, acetoguanamine, benzoguanamine, diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives. , Melamine, polyamines such as polybasic hydrazides, their organic acid salts and / or epoxy adducts, amine complexes of boron trifluoride, ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4 -Triazine derivatives such as diamino-6-xylyl-S-triazine, trimethylamine, triethanolamine, N, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) Lamin, 2,4,6-tris (dimethylaminophenol), tetramethylguanidine, DBU (1,8-diazabicyclo [5,4,0] -7-undecene), DBN (1,5-diazabicyclo [4,3 , 0] -5-nonene), etc., their organic acid salts and / or tetraphenylboronate, polyvinylphenol, polyvinylphenol bromide, tributylphosphine, triphenylphosphine, tris-2-cyanoethylphosphine, etc. Organic phosphines, quaternary phosphonium salts such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide, hexadecyltributylphosphonium chloride, tetraphenylphosphonium tetraphenylboronate, benzyltrimethylammonium chloride, Quaternary ammonium salts such as nyltributylammonium chloride, the polycarboxylic acid anhydride, diphenyliodonium tetrafluoroboroate, triphenylsulfonium hexafluoroantimonate, 2,4,6-triphenylthiopyrylium hexafluorophosphate, Irgacure 261 (manufactured by Ciba Specialty Chemicals), photocationic polymerization catalyst such as Optoma-SP-170 (manufactured by ADEKA), styrene-maleic anhydride resin, equimolar reaction product of phenyl isocyanate and dimethylamine, And an equimolar reaction product of organic polyisocyanate such as tolylene diisocyanate and isophorone diisocyanate and dimethylamine. You may use these individually or in combination of 2 or more types. Preferably, it is a curing accelerator having latent curability, and examples thereof include DBU, DBN organic acid salts and / or tetraphenylboronate, and a photocationic polymerization catalyst.

  (E) As for the usage-amount of a hardening accelerator, 0.1-20 mass parts is preferable with respect to 100 mass parts of (A) urethane-modified polyimide resin. If it exceeds 20 parts by mass, the storage stability of the urethane-modified polyimide-based flame retardant resin composition and the heat resistance of the coating film are likely to be reduced, and if it is less than 0.1 parts by mass, the curability may be reduced.

  The urethane-modified polyimide flame-retardant resin composition of the present invention can contain (F) an ion catcher in order to further improve the insulation reliability under high temperature and high humidity.

  (F) As an ion catcher, the impure ions and hydrolyzable chlorine present in the order of ppm are captured in the cured coating film of the urethane-modified polyimide flame retardant resin composition to reduce the insulation failure of the flexible printed circuit board, There is no particular limitation as long as it improves the insulation reliability. For example, organic ion exchange resin, inorganic ion exchanger (zeolite, zirconium phosphate, hydrated bismuth nitrate, antimony oxide, magnesium aluminum hydrotalcite, hydroxy Apatite). You may use these individually or in combination of 2 or more types. In view of heat resistance and chemical resistance, it is preferable to use an inorganic ion exchanger. In addition, since ions to be captured include both cations and anions, either an ion exchange type inorganic ion exchanger is used, or a cation exchange type inorganic ion exchanger and an anion exchange type inorganic ion exchanger are used. It is desirable to use together.

  As the both ion exchange type inorganic ion exchangers, those of antimony-bismuth type and zirconium-bismuth type can be used. Non-antimony-bismuth-based materials are also included. As the cation exchange type inorganic ion exchanger, a zirconium-based one or an antimony-based one can be used. As the anion exchange type inorganic ion exchanger, a bismuth type or a magnesium-aluminum type can be used. Among the anion exchange type inorganic ion exchangers, those not containing heavy metals such as antimony and bismuth are more preferable because they have high ion exchange capacity and high environmental harmony.

  The compounding amount of the ion exchanger is preferably in the range of 1.0 to 15.0% by weight based on the total amount of the composition. If the blending amount of the inorganic ion exchanger is less than 1.0% by weight, the ion trapping rate may be 50% or less, and a sufficient effect due to blending of the inorganic ion exchanger may not be obtained. In addition, when the blending amount of the inorganic ion exchanger is about 15.0% by weight, the ion trapping rate becomes 80% or more, but even if the blending amount of the inorganic ion exchanger is further increased, the ion trapping rate does not increase. In addition to problems in cost, there is a possibility that problems may occur in heat resistance, chemical resistance, low warpage and flexibility. In addition, when the cation exchange type and the anion exchange type are used in combination, the ratio of the cation exchange type and the anion exchange type ion scavenger is in the range of a weight ratio of 20:80 to 60:40. It is preferable to set to.

  If necessary, the urethane-modified polyimide flame retardant resin composition of the present invention further includes a color pigment, a dye, a polymerization inhibitor, a thickener, an antifoaming agent, a leveling agent, a coupling agent / adhesion imparting agent, Known and commonly used heat stabilizers, antioxidants, lubricants, UV absorbers, light stabilizers, light-shielding agents, quenchers, metal deactivators, antistatic agents, anti-aging agents, plasticizers, compatibilizers, etc. Additives can be added.

  The urethane-modified polyimide flame retardant resin composition of the present invention includes the components (A), (B), (C), (D), (E), and (F) described above, and other blending components as necessary. And is uniformly mixed with a roll mill, a bead mill, a mixer or the like. The mixing method is not particularly limited as long as sufficient dispersion of each component can be obtained. Multiple kneading with three rolls is preferred.

  In the urethane-modified polyimide flame-retardant resin composition of the present invention, the viscosity in a B-type viscometer described later is preferably in the range of 50 dPa · s to 2000 dPa · s at 25 ° C., and further in the range of 100 dPa · s to 800 dPa · s. preferable. 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 2000 Pa · s, the transferability of the paste to the base material is reduced during printing, and there is a tendency for voids and pinholes in the printed film to increase.

  The degree of thixotropy (thixotropic property) is also important, and the urethane-modified polyimide flame retardant resin composition of the present invention preferably has a degree of throttling of 1.1 or more, more preferably 1.8 or more, in the measurement method described later. The upper limit is preferably 10.0 or less, and more preferably 9.0 or less. If the degree of change is less than 1.1, the flow of paste after printing increases and the film thickness tends to be reduced. If it exceeds 10.0, the paste tends not to flow. The degree of change can be adjusted by the amount of component (C) added as a change degree imparting agent.

  For example, the urethane-modified polyimide flame-retardant resin composition of the present invention is cured as follows as a solder resist to obtain a cured product. That is, on printed wiring boards, flexible printed wiring boards (FPC), chip-on-films (COF), etc., by screen printing, spray coating, roll coating, electrostatic coating, curtain coating, dip coating, etc. The composition of the present invention is applied with a film thickness of 5 to 80 μm, the coating film is pre-dried at 60 to 120 ° C., and then dried at 120 to 200 ° C. Drying may be in air or in an inert atmosphere.

  The urethane-modified polyimide flame-retardant resin composition of the present invention thus obtained is useful as a film forming material for semiconductor elements and overcoat inks for various electronic components, solder resist inks, interlayer insulating films, It can also be used as a paint, coating agent, adhesive or the like.

  In order to show the effect of the present invention, examples are given below, but the present invention is not limited to these examples. The characteristic values described in the examples are measured by the following method.

<Logarithmic viscosity>
The urethane-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: Viscosity ratio of solution to pure solvent (−)
C: Solution concentration (g / dl)

<350 ° C weight loss rate>
About 15 mg each of flame retardant alone and urethane-modified polyimide resin were sampled and heated from room temperature to 100 ° C. at a heating rate of 10 ° C./min in an air atmosphere (20 ml / min) and held for 30 minutes, and then the heating rate It heated on the aluminum pan to 10 degreeC / 600 to 600 degreeC, and calculated | required the weight decreasing rate in 150 to 350 degreeC.
Equipment used: Shimadzu differential thermal and thermogravimetric simultaneous measurement device DTG-60

<Continuous printability>
Based on the following criteria, resin precipitation from the paste and increase in viscosity when the urethane-modified polyimide flame-retardant resin composition was screen-printed for 30 minutes by the method described in Example 19 were evaluated.
(Judgment) ○: No fading, resin precipitation, ink viscosity increase
×: Fading, resin precipitation, ink viscosity increase

<Fluctuation>
Using a Brookfield BH rotational viscometer, the measurement was performed in the following procedure. A paste made of a urethane-modified polyimide-based flame retardant resin composition 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 viscosity measured at 25 ° C. and 2 rpm was also calculated, and the fluctuation degree was calculated from these values according to the following equation.
Deflection = viscosity (2 rpm) / viscosity (20 rpm)

<Ink pot life>
After leaving the urethane-modified polyimide flame retardant resin composition in a sealed state at 25 ° C. for 1 month, the presence or absence of resin precipitation or gelation was evaluated based on the following criteria.
(Judgment) ○: No abnormality
Δ: Precipitate present
×: solidification

<Phosphorus content>
It was measured by wet decomposition and molybdenum blue colorimetric method. A sample obtained by curing a urethane-modified polyimide flame retardant resin composition at 165 ° C. for 2 hours is weighed into an Erlenmeyer flask in an appropriate amount according to the phosphorus concentration in the sample, 3 ml of sulfuric acid, 0.5 ml of perchloric acid Then, 3.5 ml of nitric acid was added, and the mixture was gradually decomposed by heating with an electric heater over a half day. When the solution becomes clear, it is further heated to produce white sulfuric acid smoke, allowed to cool to room temperature, this decomposition solution is transferred to a 50 ml volumetric flask, 5 ml of 2% ammonium molybdate solution and 2 ml of 0.2% hydrazine sulfate solution. Was added, and the contents were mixed well with pure water. After heating for 10 minutes in a boiling water bath and coloring, heat-cool to room temperature, deaerate with ultrasound, take the solution into an absorption cell 10 mm, and control the blank test solution with a spectrophotometer (wavelength 830 nm) Then, the absorbance was measured. The phosphorus content was determined from the calibration curve prepared previously.

<Flame retardance>
Using the polyimide film having a thickness of 25 μm as a base material, the obtained laminated film having a thickness of 15 μm was evaluated for flame retardancy according to the UL94 standard. The flame retardancy is preferably VTM-2 or higher, and most preferably VTM-0, according to UL standards.

<Bleed out>
A laminated film obtained using a polyimide film as a base material was cut into 10 cm × 10 cm. A sample conditioned at 25 ° C. and 65% for 24 hours is placed in a polyethylene bag, sealed, and left in a constant temperature bath at 25 ° C. for 1 week to 1 month. Evaluation was based on the criteria.
(Judgment) ◎: No bleeding or tackiness after 3 months
○: No bleeding after 1 month
Δ: Slightly bleed and tacky after 1 month
×: Remarkable bleed and tackiness after 1 week

<Low warpage>
A laminated film obtained using a polyimide film as a base material was cut into 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 based on the following criteria.
(Judgment) ○: Less than 2 mm in height
Δ: Height less than 10 mm
X: 10 mm or more in height

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

<Insulation resistance between lines>
A comb-shaped pattern with a line spacing of 50 μm was formed on a two-layer CCL (trade name Viroflex) manufactured by Toyobo, washed with 1% sulfuric acid, and then washed with water and dried. The entire surface of the paste was printed on the circuit, and the obtained solder resist layer was heated and cured at 160 ° C. for 120 minutes. The insulation resistance between lines when a DC voltage of 100 V was applied was measured. 10 8 or more is preferable.

<Solder heat resistance>
The laminated film obtained using the copper foil as a base material was immersed in a solder bath at 260 ° C. for 30 seconds according to JIS-C6481, and the presence or absence of appearance abnormality such as peeling or swelling was evaluated based on the following criteria.
(Judgment) ○: No appearance abnormality
Δ: Slightly abnormal appearance
×: Overall appearance abnormality

<Adhesion>
According to JIS-K5600, 100 1-mm grids were made on the laminated film obtained using the copper foil as a base material, a peel test was performed with cello tape (registered trademark), and the peel state of the grids was observed. For the laminated film obtained using the polyimide film as the base material, a peel test was conducted in the same manner, and the peeled state of the grid was evaluated based on the following criteria.
(Judgment) ○: No peeling at 100/100
Δ: 70-99 / 100
X: 0-70 / 100

<Pencil hardness>
The laminated film obtained using the copper foil as a base material was evaluated according to JIS-K5400. The pencil hardness is preferably 2H or higher, and more preferably 3H or higher.

<PCT resistance>
The laminated film obtained using the polyimide film as a base material was left in an atmosphere of 121 ° C. and 2 atm for 48 hours, and the presence or absence of appearance abnormality such as peeling or dissolution was evaluated based on the following criteria.
(Judgment) ○: No appearance abnormality
Δ: Slightly abnormal appearance
×: Overall appearance abnormality

<Chemical resistance>
A laminated film obtained using a polyimide film as a base material is immersed in each solvent of 10% HCl, 10% NaOH, isopropanol, and methyl ethyl ketone for 10 seconds, and the presence or absence of appearance abnormality such as peeling or dissolution is determined based on the following criteria. evaluated.
(Judgment) ○: No appearance abnormality even when immersed in all solvents
Δ: Slightly abnormal appearance when immersed in at least one solvent
Yes
×: The appearance of the entire surface is abnormal when immersed in at least one kind of solvent.

Production Example 1
Trimellitic anhydride (purity 99.9%, trimellitic acid content 0.1%) 166.0 mass in a four-necked 2 liter separable flask equipped with a stirrer, cooling tube, nitrogen inlet tube and thermometer Parts, polypropylene oxide adduct of bisphenol A (trade name Newpol BP-5P, molecular weight 533, manufactured by Sanyo Chemical Industries, Ltd.) 86.3 parts by mass, polypropylene glycol (trade name, SANNICS, manufactured by Sanyo Chemical Industries, Ltd.) PPG 2000, molecular weight 2000) 108 parts by mass, 84.1 parts by mass of hexamethylene diisocyanate, 125.1 parts by mass of diphenylmethane-4,4′-diisocyanate, 493.5 parts by mass of γ-butyrolactone, and 1,8-diazabicyclo [ 5.4.0] -7-Undecene (1.5 parts by mass) was charged, and the liquid temperature was 30 under a nitrogen stream. The mixture was heated to 160 ° C. and reacted for 5 hours, and then diluted with 246.8 parts by mass of diglyme, and cooled to room temperature to obtain a dark brown urethane-modified polyimide resin solution A-1 having a nonvolatile content of 40% by mass. Obtained.

Production Examples 2-5
After polymerizing in the same manner as in Example 1 using the raw materials described in Table 1, the solution was cooled to room temperature to obtain dark brown urethane-modified polyimide resin solutions A-2 to A-5 having a nonvolatile content of 40% by mass. .

Production Example 6
Trimellitic anhydride (purity 99.9%, trimellitic acid content 0.1%) 86.3 mass in a four-necked 2 liter separable flask equipped with a stirrer, condenser, nitrogen inlet tube and thermometer Parts, ethylene glycol bisanhydro trimellitate 184.4 parts by mass, polycaprolactone diol (trade name PLACEL 220, molecular weight 2000, manufactured by Daicel Chemical Industries, Ltd.) 342.4 parts by mass, diphenylmethane-4,4′-diisocyanate 250 .3 parts by mass, 784.3 parts by mass of γ-butyrolactone, and 1.5 parts by mass of 1,8-diazabicyclo [5.4.0] -7-undecene as a catalyst were charged, and the liquid temperature was 30 ° C. under a nitrogen stream. After heating to 120 ° C and reacting for 5 hours, 392.1 parts by mass of diglyme was added to dilute, and then cooled to room temperature. To give a dark brown urethane-modified polyimide resin solution A-6 minute 40 wt%.

Production Examples 7-8
After polymerizing in the same manner as in Example 6 using the raw materials described in Table 1, the solution was cooled to room temperature to obtain dark brown urethane-modified polyimide resin solutions A-7 to A-8 having a nonvolatile content of 40% by mass. .

Example 1
Based on 48.8 parts by mass of the resin content of the urethane-modified polyimide resin solution A-1 obtained in Production Example 1, jER152 (trade name of phenol novolac epoxy resin manufactured by Japan Epoxy Resin Co., Ltd.) 7.2 mass Part was added and diluted with diglyme. Furthermore, 3.2 parts by mass of Aerosil # 300 (Nippon Aerosil Co., Ltd. hydrophilic silica fine particles) as filler, 19.1 parts by mass of SANKO-BCA (Sanko Co., Ltd.) as non-halogen flame retardant, SPE -100 (manufactured by Otsuka Chemical Co., Ltd.) 19.2 parts by mass, Ucat5002 (manufactured by Sun Apro Co., Ltd.) 0.5 parts by mass as a curing accelerator, and Floren AC-326F (Kyoeisha Chemical Co., Ltd.) as an antifoam 1.5 parts by mass), and 0.5 parts by mass of BYK-358 (by Big Chemie Co., Ltd.) as a leveling agent are added, first kneaded roughly, and then repeatedly kneaded three times using a high-speed three roll. Thus, a paste made of a urethane-modified polyimide flame retardant resin composition having a uniformly dispersed filler and thixotropic properties was obtained. When the viscosity was adjusted with diglyme, the solution viscosity was 130 poise and the throttling was 2.5. Next, the paste made of the obtained urethane-modified polyimide flame retardant 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 15 μm after drying. After drying with hot air at 80 ° C. for 10 minutes, a laminated film was obtained by heating at 150 ° 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. Similarly, it was applied to a polyimide film having a thickness of 25 μm (Akane NPI manufactured by Kaneka Corporation), dried and heated to obtain a laminated film. The details and evaluation results of the obtained composition and laminated film are shown in Table 2.

Examples 2-18
Using the raw materials described in Tables 2 and 3, a urethane-modified polyimide flame retardant resin composition and a laminated film were obtained in the same manner as in Example 1. Tables 2 and 3 show details and evaluation results of the obtained compositions and laminated films.

Example 19
Urethane modification obtained in Example 5 on a copper circuit (L / S = 50/50) obtained by a subtractive method from Toyobo 2-layer CCL (trade name Viroflex, copper foil 18 μm, base material 20 μm) A paste made of a polyimide resin composition was printed on a SUS mesh plate (Murakami Co., Ltd. 150 mesh, emulsion thickness 30 μm) at a printing speed of 5 cm / sec and dried at 80 ° C. for 6 minutes in an air atmosphere. Then, the flexible printed wiring board which gave the coverlay (coating) which consists of a urethane-modified polyimide resin composition was obtained by heat-curing for 60 minutes at 165 degreeC. The thickness of the coating was 15 μm. The obtained flexible printed wiring board was excellent in flexibility and flexibility.

Comparative Examples 1-7
A urethane-modified polyimide flame retardant resin composition and a laminated film were obtained in the same manner as in Example 1 except that the raw materials listed in Table 4 were used. Table 4 shows details and evaluation results of the obtained composition and laminated film.

  As is apparent from Tables 2 to 4, the cured coating films formed from the urethane-modified polyimide flame retardant resin compositions of Examples 1 to 18 of the present invention can be cured at low temperature, have no warp, bendable, and difficult. Excellent in flame resistance, heat resistance, chemical resistance, electrical properties, and adhesion to the substrate. On the other hand, in Comparative Examples 1 to 3 and 5 to 7, the characteristics and blending amount of the flame retardant are out of the scope of the present invention, and in Comparative Example 4, the urethane-modified polyimide resin is out of the scope of the present invention. Therefore, the cured coating film formed from these urethane-modified polyimide resin flame retardant resin compositions was inferior in each characteristic.

  The urethane-modified polyimide flame retardant resin composition of the present invention is useful as a film forming material for overcoat inks for various electronic parts such as flexible printed wiring boards, solder resist inks, interlayer insulating films, paints, and coating agents. It can be used as an adhesive in a wide range of electronic devices.

Claims (13)

(A) (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) a diol compound, and (c) an aliphatic polyamine residue derivative and / or an aromatic polyamine residue derivative A urethane-modified polyimide resin having a urethane bond produced as an essential component,
(B) an epoxy resin having two or more epoxy groups per molecule;
(C) inorganic or organic filler, and (D) non-halogen flame retardant,
A urethane-modified polyimide flame retardant resin composition containing
(D) Two components of a non-halogen flame retardant: a component (D-1) having a weight loss rate of 50% to 90% at 350 ° C. in an air atmosphere and a component (D-2) having a component weight of 0% to 20%. A urethane-modified polyimide-based flame retardant resin composition characterized by comprising The weight reduction rate of the component (D-1) is 60% or more and 85% or less, and the weight reduction rate of the component (D-2) is 0% or more and 15% or less. Urethane-modified polyimide flame retardant resin composition. The urethane-modified polyimide flame retardant resin composition according to claim 1 or 2, wherein the (D) non-halogen flame retardant contains a phosphorus flame retardant that is compatible with (A) the urethane-modified polyimide resin. . The component (D-1) contains a 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide derivative, and the component (D-2) contains a phenoxyphosphazene compound. The urethane-modified polyimide flame retardant resin composition according to any one of the above. (D) The urethane-modified polyimide flame retardant resin composition according to any one of claims 1 to 3, wherein the non-halogen flame retardant includes a filler-type non-halogen flame retardant. (D-1) a phosphinic acid metal salt in which the component includes a 9,10-dihydro-9-oxa-10-phenanthrene-10-oxide derivative, and the component (D-2) is represented by the following general formula [I]; Diphosphinic acid metal salt represented by the following general formula [II], reaction product of cyanamide derivative having at least one amino group and phosphoric acid, or reaction product of cyanamide derivative having at least one amino group and cyanuric acid The urethane-modified polyimide flame retardant resin composition according to any one of claims 1 to 3, wherein the urethane-modified polyimide flame retardant resin composition is contained.

(In Formula [I] and Formula [II], R ¹ and R ² may be the same or different from each other, and linear or branched C ₁ -C ₁₀ alkyl and / or cycloalkyl and / or Aryl and / or aralkyl, R ¹ and R ² may be bonded to each other to form a ring with an adjacent phosphorus atom, R ³ is a linear or branched C _{1 to} C ₁₀ alkylene, C ₆ arylene _{cycloalkylene,} C 6 _{-C 10} of -C _10, aryl alkylene alkylarylene or _C 6 _{-C 10} in _C 6 _{~C 10,} M is, Mg, Ca, Al, Sb , Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K or a cation selected from at least one of the group consisting of protonated nitrogen bases, m is an integer of 1 to 4 Yes, Is an integer from 1 to 4, x is an integer of 1 to 4.) The urethane-modified polyimide flame retardant according to any one of claims 1 to 6, wherein the component (D-2) contains a phenoxyphosphazene compound that is liquid under conditions of 25 ° C and 101.25 hPa. Resin composition. The (b) diol compound contains (b-1) polyoxyalkylene glycol and / or (b-2) a polyalkylene oxide adduct of bisphenol represented by the following general formula [III]. Item 8. The urethane-modified polyimide flame retardant resin composition according to any one of Items 1 to 7.

(In the formula [III], R ₁ is a C _{1 to} C ₂₀ alkylene group, and R ₂ and R ₃ may be the same or different from each other, and represent hydrogen or a C _{1 to} C ₄ alkyl group. , M is an integer of 1 or more, and n is an integer of 1 or more.) (E) The urethane-modified polyimide flame retardant resin composition according to any one of claims 1 to 8, further comprising a curing accelerator. (F) The urethane-modified polyimide flame retardant resin composition according to any one of claims 1 to 9, further comprising an ion catcher. (A) A urethane-modified polyimide resin is obtained by reacting in an at least one organic solvent selected from the group consisting of an ether solvent, an ester solvent, a ketone solvent, and an aromatic hydrocarbon solvent. The urethane-modified polyimide flame retardant resin composition according to claim 1, wherein the urethane-modified polyimide flame retardant resin composition is provided.   The urethane-modified polyimide flame-retardant resin composition according to any one of claims 1 to 11, wherein the urethane-modified polyimide flame-retardant resin composition has a thixotropic property of 1.1 or more in terms of degree of change.   It is an electronic component which has a soldering resist layer, a surface protection layer, an interlayer insulation layer, or an adhesive bond layer, The said layer dries the urethane-modified polyimide flame-retardant resin composition according to any one of claims 1 to 12. An electronic component obtained by curing.