WO2019244452A1 - Adhesive composition containing acrylonitrile butadiene rubber copolymerized polyamide imide resin - Google Patents

Abstract

The present invention provides an adhesive composition which has improved solder heat resistance after moisture absorption, excellent flowability and excellent B-stage adhesive film provisional bondability, while exhibiting adhesiveness, insulation reliability, flame retardancy and B-stage adhesive film embrittlement resistance. An adhesive composition which contains (A1) a polyamide imide resin that does not contain an acrylonitrile butadiene rubber, (A2) an acrylonitrile butadiene rubber copolymerized polyamide imide resin, and (B) an epoxy resin that has two or more epoxy groups in each molecule, and which forms a homogeneous phase. With respect to this adhesive composition, (i) the A1/A2 mass ratio in the composition is from 0.1 to 1.0 (inclusive), (ii) the (A1 + A2)/B mass ratio in the composition is from 0.9 to 3.6 (inclusive), and (iii) the component (A2) is a resin which comprises, as copolymerization components, (a) a polycarboxylic acid derivative having an acid anhydride group, (b) an isocyanate compound or an amine compound, and (c) an acrylonitrile-butadiene rubber having carboxyl groups at both ends, and which is configured such that if constituent units derived from all acid components of the component (A2) is taken as 100 mol%, the ratio of the constituent unit derived from the acid component (a) is 90-99 mol%, and the ratio of the constituent unit derived from the acid component (c) is 1-5 mol%.

Description

Adhesive composition containing acrylonitrile butadiene rubber copolymerized polyamideimide resin

The present invention relates to an adhesive composition containing an acrylonitrile-butadiene rubber copolymerized polyamide-imide resin, and more particularly, to an adhesive composition having excellent adhesiveness, heat resistance, insulation, flexibility, flame retardancy, fluidity, and coverlay. The present invention relates to an adhesive composition suitable for a film, an adhesive film, a three-layer copper-clad laminate, and the like.

フ レ キ シ ブ ル Generally, flexible printed wiring boards (hereinafter also referred to as FPCs) are applied to wiring board materials and mounting substrate materials of electronic devices that require flexibility and small space. For example, a device mounting board for a display device used for a liquid crystal display device, a plasma display, an organic EL display, and the like, a relay cable between boards for a smartphone, a tablet device terminal, a digital camera, a portable game machine, and the like, an operation switch section board Widely used for.

In recent years, as electronic devices have become smaller, thinner, and more sophisticated, electronic circuits have become more highly integrated. In addition to making FPCs smaller and thinner, a single-layer FPC is laminated with an interlayer adhesive. There is a growing demand for a multilayer FPC. Therefore, a higher degree of adhesiveness, insulation reliability, humidifying solder heat resistance, and the like are required for a coverlay (hereinafter, also referred to as CL) of an FPC and an adhesive used between layers.

(4) As a measure for improving the humidifying solder heat resistance, generally, it is considered that the polarity of the resin is reduced to reduce the water absorption of the resin composition. However, when the resin polarity is reduced, the adhesiveness to a circuit material (copper foil) is reduced, so that there is a problem that it is difficult to achieve these characteristics at the same time.

By the way, the adhesive used for the FPC is obtained by applying a liquid resin composition on a release film, evaporating the solvent, winding the B-stage adhesive film into a roll, and then releasing the release film. It is used by temporarily attaching it to a circuit material such as a copper foil or a polyimide film and thermocompression bonding.

Therefore, in the winding step of the B-stage adhesive film, flexibility is required to prevent the adhesive film from cracking. In addition, when the B-stage adhesive film is temporarily attached to the circuit material, by providing the B-stage adhesive film with a temporary attaching property, roll-to-roll FPC production becomes possible, and productivity is greatly increased. Can be improved. Furthermore, in the thermocompression bonding step, it is required that the amount of the adhesive flowing out from the CL end is small.

As a resin used for the CL and the interlayer insulating layer, a solvent-soluble ring-closed polyimide resin having excellent heat resistance, insulation properties and chemical resistance has been proposed. However, in general, since a high boiling point solvent such as N-methyl-2-pyrrolidone is used as a solvent for a wholly aromatic polyimide resin varnish polymerized from only an aromatic monomer, drying / curing A high-temperature and long-time curing step of 200 ° C. or more is required, and there has been a problem that electronic components are thermally degraded.

Furthermore, since the wholly aromatic polyimide resin generally has a high glass transition temperature, the embedding property when the adhesive is thermocompression-bonded to a substrate such as a polyimide film or a copper foil is deteriorated, and the adhesive strength is reduced. There was a problem.

On the other hand, polysiloxane-modified polyimide-based resins have been disclosed in order to solve the problem of the decrease in adhesiveness (for example, see Patent Documents 1 and 2).

Regarding improvement in solvent solubility in a low boiling point solvent, a method of copolymerizing acrylonitrile butadiene having a reactive functional group in a wholly aromatic polyamideimide resin having excellent solvent solubility has been proposed (for example, Patent Document 3).

However, the polysiloxane-modified polyimide-based resins described in Patent Literatures 1 and 2 use an expensive diamine having a dimethylsiloxane bond as a starting material, and are inferior in economic efficiency. Further, there is a problem that the adhesiveness decreases with an increase in the amount of polysiloxane copolymerized. Further, in the polyamide-imide resin described in Patent Document 3, it is necessary to increase the copolymerization amount of acrylonitrile butadiene, and as a result, there is a concern that insulation reliability may be reduced.

JP-A-7-304950 JP-A-8-333455 JP 2003-289594 A

The present invention has been made in view of the problems of the related art, and has the same objects as those of the related art (1) adhesiveness, (2) insulation reliability, (3) flame retardancy, and (4). Provide an adhesive composition having (5) improved humidification solder heat resistance, (6) excellent run-out properties, and (7) excellent B-stage adhesive film temporary tackiness while having B-stage adhesive film embrittlement resistance. In particular, it is to provide an adhesive composition suitable for use in an electronic component having an interlayer insulating layer or an adhesive layer.

The present inventors have conducted intensive studies to achieve the above object, and as a result, the adhesive composition which forms a uniform phase while containing a specific component as an essential component at a specific ratio has been described above. The present inventors have found that they also have the property of 7), and have completed the present invention.

That is, the present invention has the following configurations (1) to (6).
(1) (A1) a polyamideimide resin containing no acrylonitrile butadiene rubber;
(A2) an acrylonitrile butadiene rubber copolymerized polyamide-imide resin; and (B) an epoxy resin having two or more epoxy groups per molecule as an essential component to form a uniform phase, and the following (i) to (i) An adhesive composition satisfying the condition of iii):
(I) the mass ratio of A1 / A2 in the composition is from 0.1 to 1.0;
(Ii) the mass ratio of (A1 + A2) / B in the composition is 0.9 or more and 3.6 or less;
(Iii) When (A2) is a resin containing the following components (a), (b) and (c) as copolymer components, and the structural unit derived from all the acid components of (A2) is 100 mol%. The proportions of the constituent units derived from the respective acid components are (a) 90 to 99 mol% and (c) 1 to 5 mol%:
(A) a polycarboxylic acid derivative having an acid anhydride group;
(B) an isocyanate compound or an amine compound;
(C) acrylonitrile-butadiene rubber having carboxyl groups at both ends.
(2) The polycarboxylic acid derivative of the component (a) has a valence of 3 and / or 4, and the weight average molecular weight of the component (c) is 500 to 5000, and the ratio of the acrylonitrile moiety is 10 to 50 mass%. % Of the adhesive composition according to (1).
(3) The adhesive according to (2), wherein (a) is a polycarboxylic acid derivative having an aromatic ring, and (b) is a diisocyanate compound having an aromatic ring or a diamine compound having an aromatic ring. Composition.
(4) The adhesive according to any one of (1) to (3), wherein, when thermally cured at 170 ° C. for 3 hours, the molecular weight (Mc) between crosslinking points determined by the following formula is 2,000 or less. Composition:
Molecular weight between crosslink points (Mc) = 3ρRT × 1,000,000 / E ′
Here, R = 8.31 [Jmol ⁻¹ K ⁻¹ ], E ′ and T are determined by dynamic viscoelasticity measurement, and ρ is determined by specific gravity measurement.
(5) The adhesive composition according to any one of (1) to (4), further comprising a phosphorus-based flame retardant (C).
(6) The adhesive composition according to any one of (1) to (5), wherein a value obtained by the following equation is 1.5 or more and 7.0 or less:
Mixing ratio of epoxy resin solids (parts by mass) to adhesive solids (parts by mass) × epoxy equivalent [eq / t] / ｛adhesive solids (parts by mass) of polyamideimide resin (A1) solids (parts by mass) ) × acid value of polyamide-imide resin (A1) [eq / t] + NBR copolymer Mixing ratio of polyamide-imide resin (A2) solids (parts by mass) to adhesive solids (parts by mass) × NBR copolymerization Acid value [eq / t] of polyamide-imide resin (A2) + mixing ratio of solid content of compound having phenolic hydroxyl group to adhesive solid content (parts by mass) × phenolic hydroxyl value [eq / t]｝

The adhesive composition of the present invention has the same (1) adhesiveness, (2) insulation reliability, (3) flame retardancy, and (4) B-stage adhesive film embrittlement resistance as conventional products. (5) It is suitable for use in electronic parts having an interlayer insulating layer or an adhesive layer because it has excellent humidifying solder heat resistance, (6) excellent run-out properties, and (7) excellent B-stage adhesive film tackiness. it can.

Hereinafter, the adhesive composition of the present invention will be described in detail. The adhesive composition of the present invention is a resin composition that forms a homogeneous phase while containing a specific component as an essential component at a specific ratio, and is a polyamide-imide resin (A1) containing no acrylonitrile-butadiene rubber, and acrylonitrile. Butadiene rubber copolymerized polyamide-imide resin (A2), containing epoxy resin (B) having two or more epoxy groups per molecule, more preferably containing phosphorus-based flame retardant (C).

<Polyamide imide resin (A1)>
The polyamideimide resin (A1) of the present invention is not particularly limited as long as the object of the present invention can be achieved, but (a) a trivalent and / or tetravalent polycarboxylic acid derivative having an acid anhydride group, (b) It is preferable that the resin is a resin containing an isocyanate compound or an amine compound as a copolymerization component. The polyamideimide resin (A1) of the present invention is preferably a resin having a Tg of 160 ° C. or higher.

(4) The polyamide-imide resin (A1) of the present invention is a polyamide-imide resin containing no acrylonitrile-butadiene rubber, and therefore has excellent heat resistance and insulation reliability. The polyamide-imide resin (A1) is compatible with the acrylonitrile-butadiene rubber-copolymerized polyamide-imide resin (A2) described below to form a uniform phase, thereby forming an insulating reliability of the acrylonitrile-butadiene rubber-co-polymerized polyamide-imide resin (A2). Can be improved. Further, since the acid value serving as a cross-linking point with the epoxy resin (B) as a curing agent is high, the cross-linking density of the heat-cured coating film is increased, and the heat resistance of humidified solder can be improved. Further, when Tg is 160 ° C. or higher, the outflow during thermocompression bonding can be suppressed.

Furthermore, the polyamideimide resins (A1) and (A2) generate hydroxyl groups when crosslinked with the epoxy resin (B). In particular, since the polyamideimide resin (A1) has a high acid value serving as a crosslinking point with the epoxy resin (B), more hydroxyl groups are generated during thermosetting. Since the hydroxyl group improves the affinity with ACF, the polyamideimide resin (A1) can enhance ACF adhesion.

Whether the morphology of the adhesive composition is a homogeneous phase or a phase separation depends on the domain size when the pre-treated adhesive composition is observed with a JEM 2100 transmission electron microscope manufactured by JEOL under the conditions of an acceleration voltage of 200 kV. Can be determined as follows.
Homogeneous phase: adhesive composition does not contain domains of 0.1 μm or more Phase separation: adhesive composition contains domains of 0.1 μm or more

Under the condition that the weight ratio of A1 / A2 in the adhesive composition is 0.1 or more and 1.0 or less, when the adhesive composition forms a sea-island phase separation structure, the island component does not contain acrylonitrile butadiene rubber. It contains a polyamideimide resin (A1), and the sea component contains an acrylonitrile butadiene rubber copolymerized polyamideimide resin (A2). Therefore, the morphology of the adhesive composition depends on the compatibility of the polyamideimide resin (A2) containing no acrylonitrile butadiene rubber (A1) and the acrylonitrile butadiene rubber, and the mass of the acrylonitrile butadiene rubber contained in (A2) As the amount decreases or the mass ratio of A1 / A2 decreases, the compatibility between (A1) and (A2) improves, and the adhesive composition easily forms a uniform phase.

As described above, the polyamideimide resin (A1) is preferably a resin having a glass transition temperature of 160 ° C. or higher, and a polycarboxylic acid having an aromatic ring when constituent units derived from all acid components are 100 mol%. Is preferably a resin having an anhydride of 90 mol% or more. The amount of the polyamide-imide resin (A1) is preferably 10 to 99 parts by mass, more preferably 20 to 90 parts by mass, based on 100 parts by mass of the acrylonitrile-butadiene rubber copolymerized polyamide-imide resin (A2). That is, the mass ratio of A1 / A2 in the composition is preferably from 0.1 to 1.0, more preferably from 0.2 to 0.9. If the amount is less than the above, it is difficult to obtain the effect of reducing flow-out and improve the humidifying solder, and if the amount is too large, the adhesiveness is reduced. Regarding compatibility, when the adhesive composition forms a sea-island phase-separated structure due to a decrease in compatibility, the effect of improving the insulation reliability of the acrylonitrile-butadiene rubber copolymerized polyamideimide resin (A2) is hardly obtained.

<Acrylonitrile butadiene rubber copolymerized polyamideimide resin (A2)>
The acrylonitrile butadiene rubber (hereinafter also referred to as NBR) copolymerized polyamideimide resin (A2) of the present invention comprises (a) a polycarboxylic acid derivative having an acid anhydride group, (b) an isocyanate compound or an amine compound, and (c) a carboxyl compound. A resin containing acrylonitrile butadiene rubber having groups at both ends as a copolymer component.

<(A) Polycarboxylic acid derivative having acid anhydride group>
The component (a) constituting the polyamide-imide resin (A1) and the NBR copolymerized polyamide-imide resin (A2) of the present invention has an acid anhydride group that reacts with an isocyanate component or an amine component to form a polyimide resin. A polycarboxylic acid derivative (hereinafter, also simply referred to as component (a)), for example, an aromatic polycarboxylic acid derivative, an aliphatic polycarboxylic acid derivative, or an alicyclic polycarboxylic acid derivative can be used. The valence of the polycarboxylic acid derivative is not particularly limited, but can be generally trivalent and / or tetravalent.

The aromatic polycarboxylic acid derivative is not particularly limited. For example, trimellitic anhydride, pyromellitic dianhydride, ethylene glycol bisanhydrotrimellitate, propylene glycol bisanhydrotrimellitate, 1,4 Alkylene glycol bisanhydrotrimellitates such as butanediol bisanhydrotrimellitate, hexamethylene glycol bisanhydrotrimellitate, polyethylene glycol bisanhydrotrimellitate, polypropylene glycol bisanhydrotrimellitate, 3, 3'-4,4'-benzophenonetetracarboxylic dianhydride, 3,3'-4,4'-biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthale Tetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3,3 ′, 4,4′- Diphenylsulfonetetracarboxylic dianhydride, m-terphenyl-3,3 ', 4,4'-tetracarboxylic dianhydride, 4,4'-oxydiphthalic dianhydride, 1,1,1,3, 3,3-hexafluoro-2,2-bis (2,3- or 3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3- or 3,4-dicarboxyphenyl) Propane dianhydride, 2,2-bis [4- (2,3- or 3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 1,1,1,3,3,3-hexafluoro-2 , 2-bis [4- (2,3- or 3,4-dical Kishifenokishi) phenyl] propane dianhydride, or 1,3-bis (3,4-carboxyphenyl) -1,1,3,3-tetramethyldisiloxane dianhydride, and the like.

The aliphatic or alicyclic polycarboxylic acid derivative is not particularly limited, but includes, for example, butane-1,2,3,4-tetracarboxylic dianhydride, pentane-1,2,4,5-tetracarboxylic acid 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 dianhydride, -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 acid Dianhydride, 1-propylcyclohexane-1- (2,3), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane-1- (2,3), 3- (2,3) -tetracarboxylic dianhydride, dicyclohexyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, bicyclo [2,2,1] heptane-2,3,5 6-tetracarboxylic dianhydride, bicyclo [2,2,2] octane-2,3,5,6-te Rakarubon dianhydride, bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, or hexa hydro trimellitic anhydride, and the like.

ポ リ These polycarboxylic acid derivatives having an acid anhydride group may be used alone or in combination of two or more. Considering humidified solder heat resistance, adhesiveness, solubility, cost, etc., pyromellitic anhydride, trimellitic anhydride, ethylene glycol bisanhydrotrimellitate, 3,3'-4,4'- Benzophenone tetracarboxylic dianhydride and 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride are preferred, and trimellitic anhydride and ethylene glycol bisanhydrotrimellitate are more preferred.

The copolymerization amount of the component (a) in the polyamide-imide resin (A1) or the NBR copolymerized polyamide-imide resin (A2) needs to be 90 mol% when all the acid components to be reacted are 100 mol%. And preferably at least 91 mol%. If it is less than the above range, humidified solder heat resistance and insulation reliability may not be obtained. The upper limit of the copolymerization amount of the component (a) is at most 99 mol% in consideration of the component (c).

<(B) Isocyanate compound or amine compound>
The component (b) constituting the NBR copolymerized polyamideimide resin (A2) of the present invention is not particularly limited as long as it is an isocyanate compound or an amine compound (hereinafter, also simply referred to as the component (b)). Examples include isocyanates, aliphatic or alicyclic polyisocyanates, or corresponding polyamines. Preferably, an aromatic polyisocyanate or an aromatic polyamine is used. The aromatic polyisocyanate is not particularly restricted but includes, for example, diphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- or 5,2 '-Or 5,3'- or 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4, 3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4 , 2'- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate, diphenylmethane-4,4 ' -Diisocyanate, diphenylmethane-3,3'-diisocyanate, diphenylmethane- 4,4′-diisocyanate, diphenylether-4,4′-diisocyanate, benzophenone-4,4′-diisocyanate, diphenylsulfone-4,4′-diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, naphthalene-2,6-diisocyanate, 4,4 '-[2,2bis (4-phenoxyphenyl) propane] diisocyanate, 3,3' or 2,2'- Dimethylbiphenyl-4,4'-diisocyanate, 3,3'- or 2,2'-diethylbiphenyl-4,4'-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 3,3 '-Diethoxybiphenyl-4,4'-diisocyanate It is below. In consideration of heat resistance, adhesion, solubility, cost, etc., diphenylmethane-4,4′-diisocyanate, tolylene-2,4-diisocyanate, m-xylylene diisocyanate, 3,3′- or 2,2 ′ -Dimethylbiphenyl-4,4'-diisocyanate is preferred, and 3,3'-dimethylbiphenyl-4,4'-diisocyanate and tolylene-2,4-diisocyanate are more preferred. These can be used alone or in combination of two or more. When an aromatic polyamine is used, a polyamine corresponding to the aromatic polyisocyanate can be used.

<(C) Acrylonitrile butadiene rubber having carboxyl groups at both ends>
The component (c) constituting the NBR copolymerized polyamideimide resin (A2) of the present invention is not particularly limited as long as it is an NBR having carboxyl groups at both ends (hereinafter, also simply referred to as component (c)). The component (c) is copolymerized as a flexible component that imparts adhesiveness and the like to the NBR copolymerized polyamideimide resin (A2).

The weight average molecular weight of the component (c) is preferably from 500 to 5,000, more preferably from 1,000 to 4,500, and even more preferably from 1500 to 4,000. If the molecular weight is too low, the adhesiveness and flexibility may decrease. If the molecular weight is too high, copolymerization becomes difficult due to a decrease in reactivity.

割 合 The proportion of the acrylonitrile moiety in the component (c) is preferably from 10 to 50% by mass, more preferably from 15 to 45% by mass, and even more preferably from 20 to 40% by mass. If the acrylonitrile moiety is too small, the copolymerization becomes difficult due to a decrease in compatibility, and if it is too large, insulation reliability may decrease.

The copolymerization amount of the component (c) in the NBR copolymerized polyamide-imide resin (A2) needs to be 1 to 5 mol%, preferably 2 to 4.8 mol%, based on all the acid components. And more preferably 3 to 4.6 mol%. If the copolymerization amount of the component (c) is too small, the adhesiveness and flexibility may decrease. If the copolymerization amount is too large, insulation reliability may decrease.

質量 In addition, the mass ratio of the component (c) in the adhesive composition is preferably 5 to 13% by mass, more preferably 6 to 12% by mass, based on the solid component of the adhesive. If the mass ratio of the component (c) is too small, the adhesiveness and flexibility may decrease. If the mass ratio is too large, the insulation reliability may decrease.

市 販 As a commercially available product of the component (c), for example, the CTBN series of Hypro (trade name) of CVC Thermoset Specialties, and the like can be mentioned.

<Other acid components>
The polyamide-imide resin (A1) and the NBR copolymerized polyamide-imide resin (A2) of the present invention may further contain an aliphatic, alicyclic or aromatic polycarboxylic acid, if necessary, as long as the desired performance is not impaired. It may be copolymerized. Examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decandioic acid, dodecandioic acid, eicosantioic 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-dimethyleicosandioic acid, fumaric acid , Maleic acid, dimer acid, hydrogenated dimer acid, and the like. Examples of the alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,2-cyclohexanedicarboxylic acid. Cyclohexanedicarboxylic acid, 4,4′-dicyclohexyldicarboxylic acid, etc., and aromatic dicarboxylic acids include For example, isophthalic acid, terephthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, oxydibenzoic acid, stilbenedicarboxylic acid and the like can be mentioned. These dicarboxylic acids may be used alone or in combination of two or more. Considering heat resistance, adhesion, solubility, cost, and the like, sebacic acid, 1,4-cyclohexanedicarboxylic acid, dimer acid, or isophthalic acid is preferred.

In addition to the component (c), if necessary, other flexible components may be copolymerized as long as the desired performance is not impaired. For example, aliphatic / aromatic polyester diols (manufactured by Toyobo Co., Ltd., trade name VYLON (registered trademark) 200), aliphatic / aromatic polycarbonate diols (manufactured by Daicel Chemical Industries, Ltd., trade name PLACCEL (registered trademark) ) -CD220, manufactured by Kuraray Co., Ltd., trade name C-2015N, etc.), polycaprolactone diols (produced by Daicel Chemical Industries, Ltd., trade name PLACCEL (registered trademark) -220, etc.), carboxy-modified acrylonitrile butadiene rubbers ( And polysiloxane derivatives such as polydimethylsiloxane diol, polymethylphenylsiloxane diol, and carboxy-modified polydimethylsiloxanes, etc., manufactured by CVC Thermoset Specialties, Inc., under the trade name HyproCTBN1300 × 13).

As a method for producing the polyamideimide resin (A1) and the NBR copolymerized polyamideimide resin (A2), a polycarboxylic acid component having an acid anhydride group (component (a)) and an acid component having carboxyl groups at both ends ( (C) component) and a method for producing from an isocyanate component ((b) component) (isocyanate method), or a polycarboxylic acid component having an acid anhydride group (component (a)), and an acid component having carboxyl groups at both terminals There are known methods such as a method of reacting (component (c)) with an amine component (component (b)) to form an amic acid, followed by ring closure (direct method). Industrially, the isocyanate method is advantageous.

In the case of the isocyanate method, the amount of the component (a), the component (b), and the component (c) is such that the ratio of the total of the number of acid anhydride groups + the number of carboxyl groups to the number of isocyanate groups is the ratio of the number of isocyanate groups / (the number of acid anhydride groups + It is preferable that (the number of carboxyl groups) = 0.8 to 1.2. If the ratio is less than 0.8, it becomes difficult to increase the molecular weight of the polyamideimide resin (A1) and the NBR copolymerized polyamideimide (A2), and the coating film may become brittle. When the ratio is higher than 1.2, the viscosity of the polyamideimide resin (A1) and the NBR copolymerized polyamideimide (A2) increases, and the leveling property may be deteriorated when the adhesive solution is applied.

The polymerization reaction of the polyamide-imide resin (A1) and the NBR copolymerized polyamide-imide resin (A2) used in the present invention is carried out in the presence of at least one organic solvent, for example, by the reaction of a carbon dioxide gas which is liberated by the isocyanate method from the reaction system. It is preferable to carry out the heat condensation while removing.

As the polymerization solvent, any solvent having low reactivity with isocyanate can be used. For example, a solvent not containing a basic compound such as an amine is preferable. Such solvents include, for example, toluene, xylene, ethylbenzene, nitrobenzene, cyclohexane, isophorone, diethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, dipropylene glycol methyl ether acetate, diethylene glycol ethyl Ether acetate, methyl methoxypropionate, ethyl methoxypropionate, methyl ethoxypropionate, ethyl ethoxypropionate, ethyl acetate, n-butyl acetate, isoamyl acetate, ethyl lactate, acetone, methyl ethyl ketone, cyclohexanone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolide , N- ethylpyrrolidone, .gamma.-butyrolactone, dimethyl sulfoxide, can be mentioned chloroform and methylene chloride.

重合 N, N-dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, and γ-butyrolactone are preferred as the polymerization solvent because of good volatility at the time of drying, polymer polymerizability, and good solubility. More preferred are N, N-dimethylacetamide and γ-butyrolactone.

When N-methylpyrrolidone, N-ethylpyrrolidone and the like are used in combination, the adhesive is used in the adhesive because of its high boiling point, from the viewpoint of solvent drying, and because of its high surface tension, to prevent repelling during coating. It is preferable that the mass ratio of these high-boiling solvents be 20% by mass or less based on the total amount of the contained solvents.

The amount of the solvent to be used is preferably 0.8 to 5.0 times (mass ratio) the polyamideimide resin (A1) and NBR copolymerized polyamideimide resin (A2) to be produced, and 0.9 to 2.0 times. More preferably, it is doubled. If the amount used is less than the above range, the viscosity at the time of synthesis tends to be too high and the synthesis tends to be difficult due to inability to stir. If it exceeds the above range, the reaction rate tends to decrease.

In the case of the isocyanate method, the reaction temperature is preferably from 60 to 200 ° C., more preferably from 100 to 180 ° C. When the reaction temperature is lower than the above range, the reaction time becomes too long. When the reaction temperature is higher than the above range, the monomer component may be decomposed during the reaction. In addition, a three-dimensional reaction occurs and gelation easily occurs. 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, and 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] -7-undecene), an alkali metal such as lithium methylate, sodium methylate, sodium ethylate, potassium butoxide, potassium fluoride, sodium fluoride, an alkaline earth metal compound or titanium, cobalt, The reaction may be performed in the presence of a catalyst such as a metal such as tin, zinc, and aluminum, or a metalloid compound.

<Production of polyamide-imide resin (A1)>
The polyamide-imide resin (A1) can be produced by a conventionally known method, and can be obtained, for example, by subjecting the component (a) and the component (b) to a condensation reaction (polyimide). Hereinafter, a method for producing the polyamide-imide resin (A1) of the present invention will be exemplified, but the present invention is not limited thereto.

After the components (a) and (b), the polymerization catalyst and the polymerization solvent are added to the reaction vessel and dissolved, the mixture is reacted at 80 to 190 ° C., preferably 100 to 160 ° C. for 5 hours or more with stirring under a nitrogen stream. After that, the mixture is diluted to an appropriate solvent viscosity with a polymerization solvent, and cooled to obtain a target polyamideimide resin (A1).

The polyamideimide resin (A1) of the present invention preferably has a molecular weight corresponding to a logarithmic viscosity of 0.2 to 0.4 dl / g at 30 ° C., and more preferably a logarithm of 0.3 to 0.35 dl / g. It has a molecular weight corresponding to the viscosity. When the logarithmic viscosity is less than the above range, the B-stage adhesive film may be embrittled. On the other hand, if it exceeds the above range, there is a concern that the acid value serving as a cross-linking point with the epoxy resin (B) may decrease, or the compatibility with the NBR copolymerized polyamideimide resin (A2) may decrease.

<Production of NBR copolymerized polyamideimide resin (A2)>
The NBR copolymerized polyamide-imide resin (A2) can be produced by a conventionally known method. For example, the NBR copolymerized polyamide-imide resin (A2) is obtained by subjecting a component (a) to a condensation reaction (polyimide) with a component (b) and a component (c). be able to. Hereinafter, a method for producing the NBR copolymerized polyamideimide resin (A2) of the present invention will be exemplified, but the present invention is not limited thereto.

After adding and dissolving the components (a), (b) and (c), the polymerization catalyst and the polymerization solvent in the reaction vessel, the mixture is dissolved at 80 to 190 ° C., preferably 100 to 160 ° C. while stirring under a nitrogen stream. After reacting for 5 hours or more, the mixture is diluted to an appropriate solvent viscosity with a polymerization solvent, and cooled to obtain an intended NBR copolymerized polyamideimide resin (A2).

The NBR copolymerized polyamideimide resin (A2) of the present invention preferably has a molecular weight corresponding to an logarithmic viscosity of 0.3 to 1.5 dl / g at 30 ° C., more preferably 0.4 to 1.0 dl. / G of a logarithmic viscosity. When the logarithmic viscosity is less than the above range, the B-stage adhesive film may be embrittled. On the other hand, if it exceeds the above range, it becomes difficult to dissolve in a solvent, and it is easily insoluble during polymerization. In addition, the viscosity of the varnish becomes high, which may make handling difficult.

ガ ラ ス The glass transition temperature of the NBR copolymerized polyamide-imide resin (A2) of the present invention is preferably 50 ° C or higher, more preferably 100 ° C or higher. If the temperature is lower than 50 ° C., the humidification solder heat resistance may be reduced. The upper limit is preferably 160 ° C. or lower because it is necessary to impart adhesiveness under general press lamination temperature conditions.

<Epoxy resin (B) component>
The epoxy resin (B) of the present invention is not particularly limited as long as it has two or more epoxy groups per molecule. The epoxy resin (B) is not particularly limited, but may be modified with, for example, silicone, urethane, polyimide, polyamide, or the like, or may contain a sulfur atom, a nitrogen atom, or the like in a molecular skeleton. For example, glycidyl ether epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S type, or hydrogenated products thereof, phenol novolak epoxy resin, cresol novolak epoxy resin, and glycidyl hexahydrophthalate Examples include glycidyl ester-based epoxy resins such as esters and glycidyl dimer acid, and linear aliphatic epoxy resins such as epoxidized polybutadiene and epoxidized soybean oil. Examples of these commercially available products include bisphenol A epoxy resins such as jER828 and 1001 (trade names) manufactured by Mitsubishi Chemical Corporation, and hydrogenated bisphenol A such as ST-2004 and 2007 (trade names manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.). Epoxy resins such as EXA-9726 manufactured by DIC Corporation, YDF-170 and 2004 manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., bisphenol F epoxy resins such as 2004, jER152 and 154 manufactured by Mitsubishi Chemical Corporation. Phenol novolak type epoxy resin such as Dow Chemical's trade name DEN-438, DIC Corporation's trade name HP7200, HP7200H, etc., YDCN-700 series trade name from Nippon Steel & Sumikin Chemical Co., Ltd., Nippon Kayaku Co., Ltd. Cresol novolak type epoxy resins such as EOCN-125S, 103S, 104S, etc. Flexible epoxy resin such as YD-171 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd .; Epon1031S manufactured by Mitsubishi Chemical Corporation; Araldite 0163 manufactured by Ciba Specialty Chemicals Co., Ltd .; Nagase Chemtech Multifunctional epoxy resin such as Denacol EX-611, EX-614, EX-622, EX-512, EX-521, EX-421, EX-411, EX-321 manufactured by Mitsubishi Chemical Corporation Epoxy Coat 604, manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd .; YH-434 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd .; Araldite PT810, manufactured by Ciba Specialty Chemicals Co., Ltd .; Alicyclic epoxy resin such as Celloxide 2021, EHPE3150, ERL4234 manufactured by UCC, and D Bisphenol S-type epoxy resin such as Epicron EXA-1514 (trade name) manufactured by C. Co., Ltd .; triglycidyl isocyanurate such as TEPIC (trade name) manufactured by Nissan Chemical Industries, Ltd .; and YX-4000 (trade name) manufactured by Mitsubishi Chemical Corporation. Examples include a bixylenol type epoxy resin and a bisphenol type epoxy resin such as YL-6056 (trade name, manufactured by Mitsubishi Chemical Corporation). These may be used alone or in combination of two or more. .

エ ポ キ シ Epoxy resin (B) generally contains chlorine as an impurity in the production process. However, it is required to reduce the amount of halogen from the viewpoint of reducing the environmental load, and it is known that the insulating property is reduced when there is a large amount of chlorine, particularly hydrolyzable chlorine. Therefore, the total amount of chlorine contained in the epoxy resin (B) is preferably 2000 ppm or less, more preferably 1500 ppm or less, and still more preferably 1000 ppm or less. Further, the total chlorine content in the nonvolatile component of the adhesive is preferably 500 ppm or less.

Among these epoxy resins, (B1) is preferably an epoxy resin which is liquid at room temperature from the viewpoint of imparting a tackiness to the B-stage adhesive film, and has two or more epoxy groups per molecule which are liquid at room temperature. More preferably, the epoxy resin has Examples of the epoxy resin (B1) include a bisphenol A epoxy resin and a bisphenol F epoxy resin. Further, an epoxy resin (B2) which is solid at room temperature can be used for the purpose of increasing the crosslink density of the coating film after heat curing. (B2) is preferably an epoxy resin which is solid at room temperature and has two or more epoxy groups per molecule, more preferably an epoxy resin which is solid at room temperature and has more than two epoxy groups per molecule. preferable. Examples of the polyfunctional epoxy (B2) include a phenol novolak epoxy resin and an o-cresol novolak epoxy resin having a large number of functional groups. One of (B1) and (B2) preferably has two or more epoxy groups per molecule, and both (B1) and (B2) preferably have two or more epoxy groups per molecule. preferable.

Increasing the crosslinking density of the heat-cured coating film suppresses the water absorption of the coating film under moisture absorption conditions (temperature: 40 ° C., humidity: 80% RH, 2 days) in the humidification solder heat resistance evaluation. When the thermosetting is performed for 3 hours, the molecular weight between cross-linking points determined by the following formula can be set to 2000 or less, whereby the humidifying solder heat resistance can be improved. The lower limit of the molecular weight between crosslinking points is not particularly limited, but is generally about 300.
Molecular weight between crosslinking points (Mc) = 3ρRT × 1,000,000 / E ′
Here, R = 8.31 [Jmol ⁻¹ K ⁻¹ ], E ′ and T are determined by dynamic viscoelasticity measurement, and ρ is determined by specific gravity measurement.

Although the upper limit of the epoxy group of the polyfunctional epoxy (B2) having more than two epoxy groups in one molecule is not particularly limited, it is 12 considering that commercially available products are generally 12 or less. .

The ratio of the epoxy resin (B1), which is liquid at room temperature in the composition, and the polyfunctional epoxy (B2) having more than two epoxy groups in one molecule as the epoxy resin (B) is as follows. In light of impartation, B1 / (B1 + B2) is preferably equal to or greater than 0.6, and more preferably equal to or greater than 0.65, in terms of mass ratio. The upper limit of the mass ratio is not particularly limited and is 1.0.

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

In the adhesive composition of the present invention, (A1 + A2) in order to impart a B-stage adhesive film temporary tackiness and increase the crosslink density of the heat-cured coating film to improve humidification solder heat resistance and insulation reliability. The mass ratio of / B is important. (A1 + A2) / B is preferably 0.9 or more and 3.6 or less, more preferably 1.0 or more and 3.5 or less. If the mass ratio is less than the above range, the crosslink density of the heat-cured coating film will be low, and the humidifying solder heat resistance and insulation reliability will be insufficient. It is not preferable because it becomes insufficient.

When a phosphorus-based flame retardant having a phenolic hydroxyl group is used in combination, the compound having a phenolic hydroxyl group may be an epoxy resin (B) in the same manner as the polyamideimide resin (A1) or the NBR copolymerized polyamideimide resin (A2). Acts as a thermosetting agent. Therefore, the crosslink density of the heat-cured coating film can be increased to improve the humidification solder heat resistance and insulation reliability. The amount of the epoxy resin (B) used when the phosphorus-based flame retardant having a phenolic hydroxyl group is used in combination is the total amount of the epoxy group in the epoxy resin (B) which is a thermosetting resin and the thermosetting which reacts with the epoxy group. It is necessary to determine in consideration of the balance between the acid value of the agents (A1) and (A2) + the total number of hydroxyl groups of the compound having a phenolic hydroxyl group. Therefore, the numerical value obtained by the following equation is preferably from 1.5 to 7.0, and more preferably from 2.0 to 6.0. If this value is less than the above range, there is a concern that a portion of the thermosetting agent may remain unreacted even after thermosetting due to lack of the epoxy resin (B). There is a concern that the resin (B) may remain unreacted after thermosetting. If the crosslink density of the coating film after heat curing is low, the heat resistance of the humidified solder and the insulation reliability may be reduced.
Mixing ratio of epoxy resin solids (parts by mass) to adhesive solids (parts by mass) × epoxy equivalent [eq / t] / ｛adhesive solids (parts by mass) of polyamideimide resin (A1) solids (parts by mass) ) × acid value of polyamide-imide resin (A1) [eq / t] + NBR copolymer Mixing ratio of polyamide-imide resin (A2) solids (parts by mass) to adhesive solids (parts by mass) × NBR copolymerization Acid value [eq / t] of polyamide-imide resin (A2) + mixing ratio of solid content of compound having phenolic hydroxyl group to adhesive solid content (parts by mass) × phenolic hydroxyl value [eq / t]｝

<Phosphorus flame retardant (C) component>
The adhesive composition of the present invention preferably further contains a phosphorus-based flame retardant (C). By blending the phosphorus-based flame retardant (C), the flame retardancy of the adhesive can be improved. The phosphorus-based flame retardant (C) is not particularly limited as long as it contains a phosphorus atom in the structure, but phosphazene or a phosphinic acid derivative is preferred from the viewpoint of hydrolysis resistance, heat resistance, and bleed-out. These may be used alone or in combination of two or more.

The phosphazene compound is represented by the following general formula [I] or general formula [II] (wherein X may be the same or different and represents a hydrogen, a hydroxyl group, an amino group, an alkyl group, an aryl group). , An organic group, and examples of the organic group include an alcohol group, a phenoxy group, an allyl group, a cyanophenoxy group, and a hydroxyphenoxy group, and n is an integer of 3 to 25).

Commercially available products of these phosphazene compounds include, for example, cyclic phenoxyphosphazene (manufactured by Otsuka Chemical Co., Ltd., trade names: SPB-100, SPE-100), and cyclic cyanophenoxyphosphazene (manufactured by Fushimi Pharmaceutical Co., Ltd., trade name: FP-300), cyclic hydroxyphenoxyphosphazene (manufactured by Otsuka Chemical Co., Ltd., trade name: SPH-100) and the like. These have n = 3 as a main component and have three functional groups which react with an epoxy group. In addition, phosphazene which does not have a reactive functional group with the epoxy resin (B) causes bleed-out over time, elutes free phosphorus under the influence of hydrolysis and the like under severe use conditions, and causes electrical insulation. Performance may be reduced. Therefore, a reactive phosphazene having a functional group that reacts with the epoxy resin (B) is preferable. Specific examples include cyclic hydroxyphenoxyphosphazenes having a phenolic hydroxyl group.

As the phosphinic acid derivative, a phenanthrene-type phosphinic acid derivative is preferable. For example, 9,10-dihydro-9-oxa-10phosphaphenanthrene-10-oxide (trade name: HCA, manufactured by Sanko Co., Ltd.) Benzyl-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide (trade name: BCA, manufactured by Sanko Co., Ltd.) 10- (2,5-dihydroxyphenyl) -10-H-9-oxa- And 10-phosphaphenanthrene-10-oxide (trade name: HCA-HQ, manufactured by Sanko Co., Ltd.). Among the phosphinic acid derivatives described above, HCA has reactivity with the epoxy resin (B), but it may cause bleed-out and may have poor high-temperature and high-humidity resistance. There is a need to. In addition to the above phosphorus compounds, other phosphorus compounds may be used alone or in combination of two or more, if necessary, as long as the flame retardancy, solder heat resistance and bleed out are not impaired.

Examples of the phosphorus-based flame retardant (C) include (i) a phosphorus-based flame retardant having no functional group that reacts with an epoxy group, and (ii) a phosphorus-containing flame retardant having two or more, particularly three, functional groups that react with an epoxy group. It is preferable to use a combined flame retardant. The ratio of the phosphorus-based flame retardants (i) and (ii) is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2 by mass ratio. If the amount of the phosphorus-based flame retardant (i) is large, the insulation reliability may be reduced. If the amount of the (ii) phosphorus-based flame retardant is large, the adhesiveness may be reduced.

(I) The phosphorus-based flame retardant having no functional group that reacts with the epoxy group has a role of imparting flexibility to the heat-cured adhesive because it is not taken into the crosslinked structure during heat curing. For example, the aforementioned cyclic phenoxyphosphazene (trade name: SPB-100, SPE-100, manufactured by Otsuka Chemical Co., Ltd.), cyclic cyanophenoxyphosphazene (trade name: FP-300, manufactured by Fushimi Pharmaceutical Co., Ltd.), 10- Benzyl-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide (manufactured by Sanko Co., Ltd., trade name: BCA) and phosphate ester type (manufactured by Daihachi Chemical, trade name: PX-200) Such is the case. (Ii) A phosphorus-based flame retardant having two or more functional groups that react with an epoxy group has a role of suppressing bleed-out and not lowering heat resistance by being taken into a crosslinked structure during thermosetting. For example, the aforementioned cyclic hydroxyphenoxyphosphazene (trade name: SPH-100, manufactured by Otsuka Chemical Co., Ltd.), 10- (2,5-dihydroxyphenyl) -10-H-9-oxa-10-phosphaphenanthrene-10 Oxide (manufactured by Sanko Co., Ltd., trade name: HCA-HQ) corresponds to this. Here, when the functional group that reacts with the epoxy is one, it becomes the terminal of the cross-linked structure and cuts the network, so that the effect of (ii) not lowering the heat resistance may be insufficient. .

The amount of the phosphorus-based flame retardant (C) used in the present invention is preferably such that the phosphorus content of the adhesive solids is 1.1 to 5.0, and 1.2 to 4.0. More preferably, When the phosphorus content of the adhesive solid content is less than the above range, the flame retardancy may be reduced. When the phosphorus content is more than the above range, the B-stage adhesive film embrittlement resistance may be reduced.

<Other ingredients>
The adhesive composition of the present invention includes, in addition to the polyamideimide resin (A1), NBR copolymerized polyamideimide resin (A2), epoxy resin (B) and phosphorus-based flame retardant (C), adhesiveness and chemical resistance. In order to further improve properties such as heat resistance and heat resistance, a curing accelerator (polymerization catalyst) can be added. The curing accelerator used in the present invention is not particularly limited as long as it can promote the curing reaction of the above-mentioned polyamideimide resin (A) and epoxy resin (B).

Specific examples of such a curing accelerator include, for example, 2MZ, 2E4MZ, C11Z, C17Z, 2PZ, 1B2MZ, 2MZ-CN, 2E4MZ-CN, C11Z-CN, 2PZ-CN, manufactured by Shikoku Chemical Industry Co., Ltd. Guanamines such as imidazole derivatives such as 2PHZ-CN, 2MZ-CNS, 2E4MZ-CNS, 2PZ-CNS, 2MZ-AZINE, 2E4MZ-AZINE, C11Z -AZINE, 2MA-OK, 2P4MHZ, 2PHZ, 2P4BHZ, acetoguanamine and benzoguanamine , Diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, melamine, polyamines such as polybasic hydrazide, and their organic acid salts and / or Xiaduct, boron trifluoride amine complex, triazine derivatives such as ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4-diamino-6-xylyl-S-triazine, trimethylamine, triethanol Amine, N, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) melamine, 2,4,6-tris (dimethylaminophenol), tetramethylguanidine, DBU ( Tertiary amines such as 1,8-diazabicyclo [5,4,0] -7-undecene), DBN (1,5-diazabicyclo [4,3,0] -5-nonene), organic acid salts thereof and / Or tetraphenylboroate, polyvinylphenol, polyvinylphenol bromide, tributy Organic phosphines such as phosphine, triphenylphosphine, and tris-2-cyanoethylphosphine; and tetraphosphonium such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide, hexadecyltributylphosphonium chloride, and tetraphenylphosphonium tetraphenylboroate. Quaternary ammonium salts such as quaternary phosphonium salts, benzyltrimethylammonium chloride, phenyltributylammonium chloride, the above-mentioned polycarboxylic anhydride, diphenyliodonium tetrafluoroboroate, triphenylsulfonium hexafluoroantimonate, 2,4,6-triphenyl Thiopyrylium hexafluorophosphate, Irgacure 261 (manufactured by Ciba Specialty Chemicals Co., Ltd.), Optoma-S Photo-cationic polymerization catalyst such as P-170 (manufactured by ADEKA Corporation), styrene-maleic anhydride resin, equimolar reaction product of phenyl isocyanate and dimethylamine, and organic polyisocyanate such as tolylene diisocyanate and isophorone diisocyanate and dimethylamine And the like. These may be used alone or in combination of two or more. Preferred is a curing accelerator having latent curing properties, and examples thereof include organic salts of DBU and DBN and / or tetraphenylboroate, and a cationic photopolymerization catalyst.

The amount of the curing accelerator used is preferably 0 to 20 parts by mass, when the total of the polyamideimide resin (A1) and the NBR copolymerized polyamideimide (A2) is 100 parts by mass. If it exceeds 20 parts by mass, the storage stability of the resin composition and the humidification solder heat resistance may be reduced.

The adhesive composition of the present invention has a phenolic hydroxyl group for the purpose of increasing the crosslinking density of the heat-cured coating film and improving insulation reliability and humidifying solder heat resistance, as long as the effects of the present invention are not impaired. Can be added. The compound having a phenolic hydroxyl group is not particularly limited as long as it has a phenolic hydroxyl group in the structure. A compound having a high phenolic hydroxyl group concentration is preferred from the viewpoint of solvent solubility and compatibility with the polyamideimide resin.

Commercially available products of these compounds include, for example, EP4020G, EP4050G, EP4080G, EPR5010G, EPR5030G, EP6050G manufactured by Asahi Organic Materials Co., Ltd., YS Polystar K125, K140, G125, G150 manufactured by Yashara Chemical Co., Ltd., Meiwa Kasei Co., Ltd. ) MEHC-7800 grade, MEHC-7851 grade, MEHC-7841 grade, MEH-8000 grade, MEH-7000, MEH-7600 series, MEH-7500 series, DL-series, H-4, HF-1M, HF- 3M, HF-4M, XMEH-001-01, XMEH-002-01, XMEH-003-01, Sumikanol 610 manufactured by Taoka Chemical Industry Co., Ltd., Tamanol 1010R manufactured by Arakawa Chemical Industry Co., Ltd., Tamanol 100S, Tamanol 10, Tamanoru 7509, Tamanoru 7705, Showa Denko Co., Ltd. Shownol CKM-1634, Shownol CKM-1636, Shownol CKM-1737, Shownol CKM1282, Shownol CKM-904, Shownol CKM-907, Shownol CKM-908, Shownol CKM-983, Shownol CKM-2400, Shownol CKM-941, Shownol CKM-2103, Shownol CKM-2432, Shownol CKM-5254, BKM-2620, BRP-5904, RM- 0909, BLS-2030, BLS-3574, BLS-3122, BLS-362, BLS-356, BLS-3135, CLS-3940, CLS-3950, BRS-356, BRS-621, BLL 3085, BRL-113, BRL-114, BRL-117, BRL-134, BRL-274, BRL-2584, BRL-112A, BRL-120Z, CKS-3898, SP-460B manufactured by Schenectady Chemical Company, SP- 103H, HRJ-1367, Regeitop PL2211, Gunei Chemical Co., Ltd., PR-HF-3, PR-53194, PR-53195, Sumitomo Bakelite, Nicanol HP-150, Nicanol HP-120, Nicanol HP-, manufactured by Fudoh. 100, Nicanol HP-210, DIC Plyofen 5010, Plyofen 503, TD-447 and the like.

Examples of the compound that generates a phenolic hydroxyl group by self-crosslinking during thermal curing include Fa-type benzoxazine and Pd-type benzoxazine manufactured by Shikoku Chemicals Co., Ltd., and BF-BXZ and BS-BXZ manufactured by Konishi Chemical Industries. No.

The compounding amount of the compound having a phenolic hydroxyl group is preferably 3 to 20 parts by mass when the total of the polyamideimide resin (A1) and the NBR copolymerized polyamideimide (A2) is 100 parts by mass. If the amount is less than 3 parts by mass, the effect of improving the crosslinking density is hardly obtained, and if it exceeds 20 parts by mass, the B-stage sheet may be embrittled.

高 A high heat-resistant resin can be added to the adhesive composition of the present invention for the purpose of suppressing the outflow during thermocompression bonding as long as the effects of the present invention are not impaired. The high heat-resistant resin is preferably a resin having a glass transition temperature of 160 ° C. or higher, such as the polyamideimide resin (A1). Specific examples include, but are not limited to, polyimide resins, polyetherimide resins, and polyetheretherketone resins. Further, the high heat resistant resin is preferably dissolved in a solvent. As a resin that satisfies these conditions, a resin in which the anhydride of a polycarboxylic acid having an aromatic ring is 90 mol% or more when the constitutional unit derived from all the acid components is 100 mol% is preferable. The compounding amount of these high heat-resistant resins is preferably 5 to 60 parts by mass, more preferably 6 to 50 parts by mass, based on 100 parts by mass of the NBR copolymerized polyamideimide (A2). If the amount is too small, it is difficult to obtain a flow-out suppressing effect. If the amount is too large, the tackiness of the B-stage adhesive sheet and the adhesiveness may decrease.

Glycidylamine can be added to the adhesive composition of the present invention in addition to the above-mentioned epoxy resin (B) for the purpose of reducing the flow of the adhesive at the time of lamination as long as the effects of the present invention are not impaired. The amount of glycidylamine to be added is preferably 0.01 to 5% by mass based on the total mass of the polyamideimide resin (A1), the NBR copolymerized polyamideimide (A2), and the epoxy resin (B) in the adhesive. More preferably, the content is 0.05 to 2% by mass. If the added amount of glycidylamine is too large, the fluidity of the adhesive during lamination may be too small and the embedding property of the circuit may be reduced.If the added amount is too small, a sufficient flow-out suppressing effect may not be obtained. There is. Examples of glycidylamine include TETRAD-X and TETRAD-C (trade names, manufactured by Mitsubishi Gas Chemical Co., Ltd.), GAN (trade name, manufactured by Nippon Kayaku Co., Ltd.), and ELM-120 (trade name, manufactured by Sumitomo Chemical Co., Ltd.). These may be used alone or in combination of two or more.

シ ラ ン A silane coupling agent can be added to the adhesive composition of the present invention for the purpose of improving adhesiveness, and there is no particular limitation as long as it is a conventionally known silane coupling agent. Specific examples thereof include amino silane, mercapto silane, vinyl silane, epoxy silane, methacryl silane, isocyanate silane, ketimine silane or a mixture or reaction product thereof, or a compound obtained by reacting these with a polyisocyanate. Examples of such a silane coupling agent include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylethyldiethoxysilane, bistrimethoxysilylpropylamine , Bistriethoxysilylpropylamine, bismethoxydimethoxysilylpropylamine, bisethoxydiethoxysilylpropylamine, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3- Aminosilane such as aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropylethyldiethoxysilane, γ-mercapto Mercaptosilanes such as propyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, γ-mercaptopropylethyldiethoxysilane, vinyltrimethoxysilane, vinyl Vinyl silanes such as triethoxysilane, tris- (2-methoxyethoxy) vinylsilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyldimethylethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- Epoxysilanes such as (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Methacrylsilanes such as 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, isocyanatepropyltriethoxysilane, isocyanatepropyltri Examples include isocyanate silanes such as methoxysilane, and ketimine silanes such as ketiminated propyltrimethoxysilane and ketiminated propyltriethoxysilane. These may be used alone or in combination of two or more. Among these silane coupling agents, epoxysilane has a reactive epoxy group and can react with a polyamideimide resin, which is preferable in terms of improving heat resistance and moist heat resistance. The amount of the silane coupling agent to be added is preferably 0 to 10% by mass, more preferably 0 to 5% by mass, assuming that the total nonvolatile content of the adhesive composition is 100% by mass. If the amount exceeds the above range, the heat resistance of the humidified solder may be reduced.

An organic / inorganic filler can be added to the adhesive composition of the present invention for the purpose of improving solder heat resistance as long as the effects of the present invention are not impaired. Examples of the inorganic filler include silica (SiO ₂ , Aerogel manufactured by Nippon Aerosil Co., Ltd.), alumina (Al ₂ O ₃ ), titania (TiO ₂ ), tantalum oxide (Ta ₂ O ₅ ), and zirconia (ZrO). ₂ ), silicon nitride (Si ₃ N ₄ ), barium titanate (BaO.TiO ₂ ), barium carbonate (BaCO ₃ ), lead titanate (PbO.TiO ₂ ), lead zirconate titanate (PZT), titanic acid zirconate, lead lanthanum (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), b Thoria containing zirconia _{(Y 2 O 3 -ZrO 2)} , barium silicate (BaO · 8SiO _2), boron nitride (BN), calcium carbonate (CaCO _3), calcium sulfate (CaSO _4), zinc oxide (ZnO), titanium magnesium acid (MgO · _TiO 2), barium sulfate (BaSO _4), organic bentonite, carbon (C), organized smectite (Co-op Chemical Co., Ltd. trade name Lucentite (registered trademark) STN, Lucentite SPN, Lucentite SAN, Lucentite SEN) can be used, and these may be used alone or in combination of two or more.

無機 As the inorganic filler used in the present invention, those having an average particle diameter of 50 μm or less and a maximum particle diameter of 100 μm or less are preferable, the average particle diameter is 20 μm or less, and the average particle diameter is 10 μm or less is most preferable. The average particle diameter (median diameter) here is a value obtained on a volume basis using a laser diffraction / scattering type particle size distribution analyzer. If the average particle diameter exceeds 50 μm, the B-stage adhesive film may be embrittled or appearance defects may occur.

有機 Examples of the organic filler used in the present invention include polyimide resin particles, benzoguanamine resin particles, and epoxy resin particles.

The adhesive composition of the present invention includes a silicone-based, fluorine-based, polymer-based antifoaming agent, and a leveling agent for the purpose of improving the leveling property and defoaming property at the time of application, as long as the effects of the present invention are not impaired. Agents can be added.

配合 The total amount of these other components is preferably less than 25% by mass when the non-volatile content of the adhesive composition is 100% by mass. That is, by setting the blending amount of A1 + A2 + B + C, which is the main component, to 75% by mass or more, desired adhesive properties can be exhibited.

<Adhesive composition (adhesive)>
The adhesive composition (adhesive) of the present invention contains the aforementioned polyamide-imide resin (A1) component, NBR copolymerized polyamide-imide (A2), and epoxy resin (B) component, and optionally contains a phosphorus-based flame retardant (C). ) A composition containing a component. Further, if necessary, other compounding components can be compounded in the above-described ratio. Thereby, it can be used as a suitable adhesive for a flexible printed wiring board.

<Adhesive solution>
The adhesive solution is obtained by dissolving the adhesive composition (adhesive) of the present invention in the polymerization solvent. The adhesive solution has a viscosity of preferably 3 dPa · s to 30 dPa · s at 25 ° C. with a B-type viscometer, and more preferably 4 dPa · s to 20 dPa · s. If the viscosity is less than the above range, the amount of the solution flowing out at the time of application becomes large, and the film thickness tends to be thin. When the viscosity exceeds the above-mentioned range, the leveling property to the base material during coating tends to decrease.

<Adhesive film>
For example, the solvent can be distilled off from the adhesive solution as follows to obtain an adhesive film. That is, the above-mentioned adhesive solution is applied to the release film with a thickness of 5 to 80 μm by a method such as a screen printing method, a spray method, a roll coating method, an electrostatic coating method, a curtain coating method, etc. Dry at ~ 150 ° C for 3-10 minutes and evaporate the solvent. Drying may be in air or in an inert atmosphere.

In addition, for the purpose of adjusting the fluidity of the adhesive at the time of thermocompression bonding, a heat treatment may be performed after drying the solvent to partially react the polyamideimide resin with the epoxy resin. The state before the thermocompression bonding is called a B stage.

部位 The parts where the adhesive is used in the FPC include a CL film, an adhesive film, and a three-layer copper-clad laminate.

For CL films and adhesive films, it is common to perform processing such as winding, storage, cutting, and punching in the B-stage state, and flexibility in the B-stage state is also required. On the other hand, in a three-layer copper-clad laminate, thermocompression bonding and thermosetting are generally performed immediately after the formation of the B-stage state.

In any of the above applications, the B-stage adhesive film is thermocompression-bonded to the adherend and subjected to a thermosetting treatment before use.

CL film consists of insulating plastic film / adhesive layer or insulating plastic film / adhesive layer / protective film. The insulating plastic film is a film having a thickness of 1 to 200 μm made of a plastic such as polyimide, polyamide imide, polyester, polyphenylene sulfide, polyether sulfone, polyether ether ketone, aramid, polycarbonate, and polyarylate. May be laminated. The protective film is not particularly limited as long as it can be peeled off without impairing the properties of the adhesive, for example, plastics such as polyethylene, polypropylene, polyolefin, polyester, polymethylpentene, polyvinyl chloride, polyvinylidene fluoride, and polyphenylene sulfide. Examples thereof include films, films obtained by coating these with silicone, fluoride, or other release agents, paper laminated with these, paper impregnated or coated with a releasable resin, and the like.

The adhesive film has a structure in which a protective film is provided on at least one surface of an adhesive layer made of an adhesive, and has a structure of protective film / adhesive layer or protective film / adhesive / protective film. In some cases, an insulating plastic film layer is provided in the adhesive layer. The adhesive film can be used for a multilayer printed circuit board.

The three-layer copper-clad laminate has a configuration in which a copper foil is bonded to at least one surface of an insulating plastic film with an adhesive. The copper foil is not particularly limited, but rolled copper foil and electrolytic copper foil conventionally used for flexible printed wiring boards can be used.

(4) The polyamideimide resin layer of the FPC thus obtained becomes a solder resist layer, a surface protection layer, an interlayer insulating layer, or an adhesive layer of a flexible printed wiring board. As described above, the polyamide-imide resin composition of the present invention is useful as a film-forming material in overcoat inks for semiconductor elements and various electronic components, solder resist inks, interlayer insulating films, paints, coating agents, adhesives, and the like. Can also be used as Here, the solder resist layer is a film that is formed on the entire surface of the circuit conductor except for the part to be soldered.When wiring electronic components on a printed wiring board, it is necessary to prevent solder from adhering to unnecessary parts. It is used as a protective film to prevent and prevent the circuit from being directly exposed to air. The surface protective layer is used to be attached to the surface of the circuit member to mechanically and chemically protect the electronic member from a processing step and a use environment. The interlayer insulating layer is used to prevent a current from flowing between layers in the package substrate on which fine wiring is formed. The adhesive layer is mainly used for bonding a metal layer and a film layer and performing a bonding process.

Examples will be given below to describe the present invention more specifically, but the present invention is not limited thereto. The evaluation of the characteristic values in the examples was performed by the following method.

<Logarithmic viscosity>
Polyamideimide resin (A1) or NBR copolymerized polyamideimide resin (A2) was dissolved in N-methyl-2-pyrrolidone so that the polymer concentration became 0.5 g / dl. The solution viscosity and the solvent viscosity of the solution were measured at 30 ° C. using an Ubbelohde type viscosity tube and calculated by the following formula.
Logarithmic viscosity (dl / g) = [ln (V1 / V2)] / V3
V1: Calculated from the time when the solvent (N-methyl-2-pyrrolidone) passes through the capillary of the Ubbelohde type viscosity tube V2: Calculated from the time when the polymer solution passes through the capillary of the Ubbelohde type viscosity tube V3: Polymer concentration (g / dl) )

<Acid value>
0.2 g of the polyamide-imide resin (A1) or NBR copolymerized polyamide-imide resin (A2) is dissolved in 20 ml of N-methylpyrrolidone, and titrated with a 0.1N ethanol solution of potassium hydroxide to obtain 10% of component (A). The equivalent weight per 6 g (equivalent / 10/10 g) was determined.

<Adhesiveness>
The adhesive solution was applied to a polyimide film (Apical 12.5 NPI manufactured by Kaneka) so that the thickness after drying was 20 μm, and dried at 140 ° C. for 3 minutes with a hot-air drier to obtain a B-stage adhesive film. The adhesive-coated surface of the B-stage adhesive film and the glossy surface of the copper foil (BHY thickness: 18 μm, manufactured by JX Nippon Oil & Gas Co., Ltd.) are thermocompressed with a vacuum press laminator under reduced pressure at 160 ° C., 3 MPa and 30 seconds. It was cured by heating at 170 ° C. for 3 hours. Using a tensile tester (Autograph AG-X plus manufactured by Shimadzu), the cured laminated material was peeled off the polyimide film at a speed of 50 mm / min in a direction of 90 ° at a speed of 50 mm / min in an atmosphere of 25 ° C, and the adhesive strength was measured. did.
：: Adhesion strength of 0.6 N / mm or more or breakage of polyimide film ×: Adhesion strength of less than 0.6 N / mm

<Insulation reliability>
A B-stage adhesive film was prepared in the same manner as in the evaluation of the adhesiveness, and thermocompression bonded to a comb pattern of L / S = 50/50 μm under reduced pressure at 160 ° C., 3 MPa for 30 seconds using a vacuum press laminating machine. At 170 ° C. for 3 hours. Under an environment of a temperature of 85 ° C. and a humidity of 85%, a voltage of 200 V was applied for 250 hours.
：: Resistance value of 1 × 10 ⁸ Ω or more and no dendrites after 250 hours ×: Resistance value of less than 1 × 10 ⁸ Ω and dendrites after 250 hours XX: Short circuit within 250 hours

<Flow out>
As in the case of the insulation reliability evaluation, the B-stage adhesive film was thermocompression-bonded to a comb pattern of L / S = 50/50 μm using a vacuum press laminator under reduced pressure at 160 ° C., 3 MPa for 30 seconds, and the CL end portion. The amount of the adhesive flowing out between the wirings was measured with a microscope.
：: Flow amount less than 100 μm ×: Flow amount 100 μm or more

<Humidifying solder heat resistance>
A laminated material cured by heating in the same manner as in the evaluation of the adhesiveness was prepared, cut into 20 mm squares, and allowed to stand in an environment of a temperature of 40 ° C. and a humidity of 80% RH for 2 days. And floated for 1 minute.
○: no swelling or peeling ×: swelling or peeling

<Adhesive composition morphology measurement>
The adhesive solution was applied to a glossy surface of a copper foil (BHY, manufactured by JX Nippon Oil & Gas Co., Ltd., thickness: 18 μm) so that the thickness after drying became 20 μm, and heat-cured at 170 ° C. for 3 hours. The obtained sample was embedded in an epoxy resin, and a frozen section was prepared using a cryomicrotome. The prepared section was stained in OsO4 vapor for 30 minutes and carbon-deposited. Observation was performed using a JEM 2100 transmission electron microscope manufactured by JEOL Ltd. under an acceleration voltage of 200 kV.
：: The adhesive composition does not contain a domain of 0.1 μm or more and forms a uniform phase. ×: The adhesive composition contains a domain of 0.1 μm or more and forms a sea-island phase-separated structure.

<Flame retardant>
A B-stage adhesive film was prepared in the same manner as in the evaluation of the adhesiveness, and the adhesive-coated surface and the polyimide film (Kaneka's Apical 12.5NPI) were used at 160 ° C., 3 MPa for 30 seconds under reduced pressure using a vacuum press laminating machine. And then heat-cured at 170 ° C. for 3 hours. Samples after curing were evaluated for flame retardancy in accordance with UL-94 VTM standard.
：: Equivalent to VTM-0 ×: Does not satisfy VTM-0

<B-stage adhesive film embrittlement resistance>
The adhesive solution was applied on a PET film (E5101, manufactured by Toyobo Co., Ltd., thickness: 50 μm) so that the thickness after drying became 20 μm, and dried at 140 ° C. for 3 minutes with a hot air drier to obtain a B-stage adhesive film. The adhesive was rolled outward and bent 180 °, and a 1 kg bell was placed.
：: no cracks in the adhesive film ×: cracks in the adhesive film

<B-stage adhesive film tackiness>
The adhesive coated surface of the B-stage adhesive film and the glossy surface of the copper foil (BHY made by JX Nippon Oil & Steel Co., Ltd., BHY thickness: 18 μm) obtained in the same manner as in the evaluation of the B-stage adhesive film embrittlement resistance were subjected to 90 ° C., 0 ° C. with a roll laminator. Thermocompression bonding was performed under the conditions of 0.3 MPa and 0.75 m / min.
：: The adhesive film was completely transferred to the copper foil △: A part of the adhesive film was transferred to the copper foil, and a part was left on the PET film, and was broken. ×: The adhesive film was not transferred to the copper foil at all, Remains on PET film

<ACF adhesion>
An adhesive solution is applied to the non-glossy surface of the rolled copper foil (JX Nikko Nisseki's BHY thickness: 12 μm) so that the thickness after drying becomes 3.5 μm, and dried at 140 ° C. for 3 minutes with a hot air drier. A B-stage adhesive film was obtained. The adhesive-coated surface of the B-stage adhesive film and the polyimide film (Apical 12.5NPI manufactured by Kaneka) are thermocompressed at 130 ° C., 2 MPa, and 5 seconds under reduced pressure using a vacuum press laminating machine to form a copper foil / adhesive / A three-layer single-sided CCL made of a polyimide film was obtained. Further, a 5-stage double-sided CCL composed of copper foil / adhesive / polyimide film / adhesive / copper foil is prepared by thermocompression bonding a B-stage adhesive film to the polyimide surface of the obtained laminate in the same manner. Then, it was cured by heating at 100 ° C. for 2 hours and then at 200 ° C. for 3 hours.
Next, the obtained double-sided CCL was patterned at L / S = 0.1 / 0.1 mm and cut into a size of 10 × 30 mm. The patterned double-sided FPC and the ACF (AC-7106 manufactured by Hitachi Chemical Co., Ltd.) were temporarily attached by thermocompression bonding at 80 ° C., 1 MPa, and 5 seconds. (1.3 mm) was thermocompressed at 180 ° C., 2 MPa, for 15 seconds.
With respect to the obtained FPC / ACF / soda glass laminate, the FPC was peeled off at a rate of 50 mm / min in a direction of 90 ° at a speed of 50 mm / min using a tensile tester in an atmosphere of 25 ° C., and the adhesive strength was measured.
：: Adhesion strength of 0.5 N / mm or more or FPC material fracture x: Adhesion strength of less than 0.5 N / mm

<Molecular weight between crosslinking points>
It was calculated by the following equation.
Molecular weight between crosslinking points (Mc) = 3ρRT × 1,000,000 / E ′
However, R = 8.31 [Jmol ⁻¹ K ⁻¹ ], E ′ and T were determined by dynamic viscoelasticity measurement, and ρ was determined by specific gravity measurement.

<Dynamic viscoelasticity measurement>
The adhesive solution was applied to a glossy surface of a copper foil (BHY, manufactured by JX Nippon Oil & Gas Co., Ltd., thickness: 18 μm) so that the thickness after drying became 20 μm, and heat-cured at 170 ° C. for 3 hours. After the obtained sample was etched to remove the copper foil, the sample was cut into strips having a width of 10 mm and a thickness of 20 μm, and were measured at a frequency of 110 Hz using a dynamic viscoelasticity measuring device DVA-220 manufactured by IT Measurement Control Co., Ltd. The dynamic viscoelasticity was measured. The lowest storage elastic modulus in the rubber-like flat region was E ', and the temperature at that time was T.

<Specific gravity measurement>
The adhesive solution was applied to a glossy surface of a copper foil (BHY, manufactured by JX Nippon Oil & Gas Co., Ltd., thickness: 18 μm) so that the thickness after drying became 20 μm, and heat-cured at 170 ° C. for 3 hours. After the obtained sample was etched to remove the copper foil, the specific gravity of each sample at 23 ° C. was measured using a Shimadzu specific gravity measuring device SGM-300P according to JIS Z88078 (in-liquid weighing method). .

(Production Example 1) Synthesis of polyamide-imide resin (A1-1) 268.98 g (1.40 mol) of trimellitic anhydride, 315.32 g (1.26 mol) of 4,4′-diphenylmethane diisocyanate (MDI) as a diisocyanate ) Was added and dissolved in 710.09 g of N-methyl-2-pyrrolidone. Thereafter, the mixture was reacted at 140 ° C. for 5 hours while stirring under a nitrogen stream, diluted with 169.07 g of dimethylacetamide, and cooled to room temperature to obtain a brown viscous polyamideimide having a nonvolatile content of 35% by mass. A resin solution (A1-1) was obtained.

(Production Example 2) Synthesis of NBR copolymerized polyamide-imide resin (A2-1) 248.54 g (1.29 mol) of trimellitic anhydride, 225.40 g (0.06 mol) of NBR, and 8.49 g (0%) of sebacic acid 4.04 mol) and 353.85 g (1.41 mol) of 4,4'-diphenylmethane diisocyanate (MDI) as a diisocyanate were dissolved in 1069.59 g of dimethylacetamide. Thereafter, the mixture was reacted at 140 ° C. for 5 hours with stirring under a nitrogen stream, diluted with 594.22 g of dimethylacetamide, and cooled to room temperature to obtain a brown viscous NBR having a nonvolatile content of 30% by mass. A polymerized polyamideimide resin solution (A2-1) was obtained.

(Production Example 3) Synthesis of NBR copolymerized polyamide-imide resin (A2-2) 256.61 g (1.34 mol) of trimellitic anhydride, 225.40 g (0.06 mol) of NBR, and 4,4′- as diisocyanate 352.10 g (1.41 mol) of diphenylmethane diisocyanate (MDI) was added and dissolved in 1066.32 g of dimethylacetamide. Thereafter, the mixture was reacted at 140 ° C. for 5 hours with stirring under a nitrogen stream, diluted with 592.40 g of dimethylacetamide, and cooled to room temperature to obtain a brown viscous NBR having a nonvolatile content of 30% by mass. A polymerized polyamideimide resin solution (A2-2) was obtained.

(Production Example 4) Synthesis of NBR copolymerized polyamideimide resin (A2-3) 262.26 g (1.37 mol) of trimellitic anhydride, 122.50 g (0.04 mol) of NBR, and 4,4′- as a diisocyanate 353.85 g (1.41 mol) of diphenylmethane diisocyanate (MDI) was added and dissolved in 921.23 g of dimethylacetamide. Thereafter, the mixture was reacted at 140 ° C. for 5 hours while stirring under a nitrogen stream, diluted with 511.79 g of dimethylacetamide, and cooled to room temperature to obtain a brown viscous NBR having a nonvolatile content of 30% by mass. A polymerized polyamideimide resin solution (A2-3) was obtained.

(Production Example 5) Synthesis of NBR copolymerized polyamideimide resin (A2-4) 256.61 g (1.34 mol) of trimellitic anhydride, 225.40 g (0.06 mol) of NBR, and 4,4′- as diamine 280.34 g (1.41 mol) of diaminodiphenylmethane was added and dissolved in 1067.17 g of dimethylacetamide. Thereafter, the mixture was reacted at 80 ° C. for 4 hours while stirring under a nitrogen stream. Thereafter, the mixture was further reacted at 150 ° C. for 10 hours, diluted with 592.87 g of dimethylacetamide, and cooled to room temperature to obtain a brown viscous NBR copolymer polyamideimide resin solution (A2) having a nonvolatile content of 30% by mass. -4) was obtained.

(Comparative Production Example 1) Synthesis of NBR copolymerized polyamideimide resin (A2-5) 252.84 g (1.32 mol) of trimellitic anhydride, 294.00 g (0.08 mol) of NBR, and 4,4 ′ as diisocyanate 353.85 g (1.41 mol) of diphenylmethane diisocyanate (MDI) was charged and dissolved in 1164.35 g of dimethylacetamide. Thereafter, the mixture was reacted at 140 ° C. for 5 hours while stirring under a nitrogen stream, diluted with 646.86 g of dimethylacetamide, and cooled to room temperature to obtain a brown viscous NBR having a nonvolatile content of 30% by mass. A polymerized polyamideimide resin solution (A2-5) was obtained.

(Comparative Production Example 2) Synthesis of NBR copolymerized polyamide-imide resin (A2-6) 221.91 g (1.15 mol) of trimellitic anhydride, 122.50 g (0.04 mol) of NBR, 42.47 g of sebacic acid ( 0.21 mol) and 352.10 g (1.41 mol) of 4,4'-diphenylmethane diisocyanate (MDI) as a diisocyanate were dissolved in 922.71 g of dimethylacetamide. Thereafter, the mixture was reacted at 140 ° C. for 5 hours with stirring under a nitrogen stream, diluted with 512.62 g of dimethylacetamide, and cooled to room temperature to obtain a brown viscous NBR having a nonvolatile content of 30% by mass. A polymerized polyamideimide resin solution (A2-6) was obtained.

Table 1 shows details of Production Examples 1 to 5 and Comparative Production Examples 1 and 2.

(Examples 1 to 9 and Comparative Examples 1 to 7)
According to the compounding ratio shown in Table 2, the polyamideimide resin (A1), the NBR copolymerized polyamideimide resin (A2-1 to 6), the epoxy resin (B), the flame retardant (C), and the like are mixed, and the adhesive solution is mixed. It was prepared and evaluated for the properties described above.

Table 2 shows details of the mixing ratios and the evaluation of the properties of the adhesive solutions of Examples 1 to 9 and Comparative Examples 1 to 7.

As is clear from Table 2, in Examples 1 to 9, a uniform phase was formed while having a specific component, and the copolymerization amount of the component (a) in the NBR copolymerized polyamideimide resin (A2) was 90 mol. % Or more and the mass ratio of A1 / A2 is 0.1 or more and 1.0 or less, so that the humidification solder heat resistance, insulation reliability, and flow out during thermocompression bonding were good. Further, by setting the mass ratio of (A1 + A2) / B to 0.9 or more and 3.6 or less, the B-stage adhesive film temporary adhesion was also good.
On the other hand, in Comparative Example 1, since the copolymerization amount of the component (c) in the NBR copolymerized polyamide-imide resin (A2) was large, the adhesive composition formed a sea-island phase-separated structure, resulting in poor insulation reliability. . In Comparative Example 2, since the polyamideimide resin (A1) containing no NBR was not included, the resin flowed out, and the insulation reliability and ACF adhesion were poor. Further, the heat resistance of the humidified solder was poor due to the increase in the molecular weight between the crosslinking points. In Comparative Example 3, since the A1 / A2 weight ratio exceeded 1.0, the adhesiveness was poor. In Comparative Example 4, since the copolymerization amount of sebacic acid in the NBR copolymerized polyamide-imide resin (A2) was large and the copolymerization amount of the component (a) was small, the outflow occurred and the humidification solder heat resistance was poor. In Comparative Example 5, since the amount of the epoxy (B1) liquid at room temperature was small and the (A1 + A2) / B weight ratio exceeded 3.6, the tackiness of the B-stage adhesive film was poor, and further, the adhesive was used as an adhesive. Due to the high NBR content, insulation reliability was poor. In Comparative Example 6, since the (A1 + A2) / B weight ratio was less than 0.9, insulation reliability and humidification solder heat resistance were poor. Comparative Example 7 did not contain the NBR copolymerized polyamideimide resin (A2) at all, and thus had poor adhesion, B-stage adhesive film embrittlement resistance, and B-stage adhesive film temporary adhesion.

The adhesive composition of the present invention has improved adhesiveness, insulation reliability, flame retardancy, B-stage adhesive film embrittlement resistance, improved humidification solder heat resistance, and further has flowability, B-stage adhesive film. Since it is excellent in tacking property, it is particularly suitable for use in an electronic component having an interlayer insulating layer or an adhesive layer. Therefore, it is useful for overcoat ink, solder resist ink, interlayer insulation film for various electronic parts such as flexible printed wiring boards, and can be used in a wide range of electronic devices as paints, coatings, adhesives, etc. It is expected to greatly contribute to the world.

Claims (6)

1. (A1) a polyamideimide resin containing no acrylonitrile butadiene rubber;
   (A2) an acrylonitrile butadiene rubber copolymerized polyamide-imide resin; and (B) an epoxy resin having two or more epoxy groups per molecule as an essential component to form a uniform phase, and the following (i) to (i) An adhesive composition satisfying the condition of iii):
   (I) the mass ratio of A1 / A2 in the composition is from 0.1 to 1.0;
   (Ii) the mass ratio of (A1 + A2) / B in the composition is 0.9 or more and 3.6 or less;
   (Iii) When (A2) is a resin containing the following components (a), (b) and (c) as copolymer components, and the structural unit derived from all the acid components of (A2) is 100 mol%. The proportions of the constituent units derived from the respective acid components are (a) 90 to 99 mol% and (c) 1 to 5 mol%:
   (A) a polycarboxylic acid derivative having an acid anhydride group;
   (B) an isocyanate compound or an amine compound;
   (C) acrylonitrile-butadiene rubber having carboxyl groups at both ends.
2. The polycarboxylic acid derivative of the component (a) is trivalent and / or tetravalent, the weight average molecular weight of the component (c) is 500 to 5000, and the ratio of the acrylonitrile moiety is in the range of 10 to 50% by mass. The adhesive composition according to claim 1, wherein:
3. 3. The adhesive composition according to claim 2, wherein (a) is a polycarboxylic acid derivative having an aromatic ring, and (b) is a diisocyanate compound having an aromatic ring or a diamine compound having an aromatic ring. 4.
4. The adhesive composition according to any one of claims 1 to 3, wherein, when thermally cured at 150 ° C for 4 hours, the molecular weight between crosslinking points (Mc) determined by the following formula is 2,000 or less:
   Molecular weight between crosslinking points (Mc) = 3ρRT × 1,000,000 / E ′
   Here, R = 8.31 [Jmol ⁻¹ K ⁻¹ ], E ′ and T are determined by dynamic viscoelasticity measurement, and ρ is determined by specific gravity measurement.
5. (5) The adhesive composition according to any one of (1) to (4), further comprising a phosphorus-based flame retardant (C).
6. The adhesive composition according to any one of claims 1 to 5, wherein a numerical value obtained by the following formula is 1.5 or more and 7.0 or less.
   Mixing ratio of epoxy resin solids (parts by mass) to adhesive solids (parts by mass) × epoxy equivalent [eq / t] / ｛adhesive solids (parts by mass) of polyamideimide resin (A1) solids (parts by mass) ) × acid value of polyamide-imide resin (A1) [eq / t] + NBR copolymer Mixing ratio of polyamide-imide resin (A2) solids (parts by mass) to adhesive solids (parts by mass) × NBR copolymerization Acid value [eq / t] of polyamide-imide resin (A2) + mixing ratio of solid content of compound having phenolic hydroxyl group to adhesive solid content (parts by mass) × phenolic hydroxyl value [eq / t]｝