JP7114983B2 - Adhesives, film-like adhesives, adhesive layers, adhesive sheets, resin-coated copper foils, copper-clad laminates, printed wiring boards, multilayer wiring boards, and methods for producing the same - Google Patents

Description

The present invention relates to an adhesive, a film-like adhesive, an adhesive layer, an adhesive sheet, a resin-coated copper foil, a copper-clad laminate, a printed wiring board, a multilayer wiring board, and a method for producing the same.

Various known adhesives are used to manufacture mobile communication devices such as mobile phones and smart phones, their base station devices, network-related electronic devices such as servers and routers, and printed wiring boards included in large computers. there is

The applicant of the present application describes "a polyimide adhesive composition containing a polyimide resin, a thermosetting resin, a flame retardant, and an organic solvent obtained by reacting diamines containing 30 mol% or more of an aromatic tetracarboxylic acid and a specific dimer diamine. (see Patent Document 1).

Japanese Patent No. 5534378

In recent years, network-related electronic devices need to transmit and process a large amount of information at low loss and at high speed, and the electrical signals handled by the printed wiring boards of these products are also increasing in frequency. Since high-frequency electrical signals are easily attenuated, it is necessary to further reduce transmission loss in printed wiring boards. Therefore, adhesives generally used for printed wiring boards are required to have a low dielectric constant and a low dielectric loss tangent (also referred to as low dielectric properties).

However, Patent Literature 1 does not consider moisture absorption solder heat resistance and low dielectric properties. In addition, before the reflow process, the printed wiring board is often pre-dried at a temperature of 100 to 120° C. in order to suppress foaming and blistering due to moisture absorption. Recently, however, the number of cases where a solder reflow process is performed without performing a pre-drying process has increased in order to improve production efficiency. When the solder reflow process is performed without pre-drying, solder heat resistance at a reflow temperature of about 260° C. is required, for example. Therefore, there has been a demand for an adhesive capable of forming an adhesive layer (cured product) that is excellent in room-temperature adhesiveness, solder heat resistance in a hygroscopic state (hygroscopic solder heat resistance), and low dielectric properties.

As a result of intensive studies, the present inventors have found that the above problems can be solved by an adhesive containing a predetermined polyimide.

（式中、Ｙはフェニレン基又はシクロヘキシレン基を表す。）
のエポキシドである、上記項目のいずれか１項に記載の接着剤。
（項目６）
高軟化点ポリイミドと低軟化点ポリイミドの合計１００質量部（固形分換算）に対し、架橋剤を５～９００質量部、かつ有機溶剤を１５０～９００質量部含む、上記項目のいずれか１項に記載の接着剤。
（項目７）
上記項目のいずれか１項に記載の接着剤の加熱硬化物を含む、フィルム状接着材。
（項目８）
上記項目のいずれか１項に記載の接着剤又は上記項目のフィルム状接着材を含む、接着層。
（項目９）
上記項目に記載の接着層及び支持フィルムを含む、接着シート。
（項目１０）
上記項目に記載の接着層及び銅箔を含む、樹脂付銅箔。
（項目１１）
上記項目に記載の樹脂付銅箔及び銅箔を含む、銅張積層板。
（項目１２）
上記項目に記載の樹脂付銅箔及び絶縁性シートを含む、銅張積層板。
（項目１３）
上記項目のいずれか１項に記載の銅張積層板の銅箔面に回路パターンを有する、プリント配線板。
（項目１４）
プリント配線板（１）又はプリント回路板（１）、
上記項目に記載の接着層、及び
プリント配線板（２）又はプリント回路板（２）を含む、
多層配線板。
（項目１５）
下記工程１及び２を含む多層配線板の製造方法。
工程１：上記項目のいずれか１項に記載の接着剤又は上記項目に記載のフィルム状接着材を、プリント配線板（１）又はプリント回路板（１）の少なくとも片面に接触させることによって、接着層付基材を製造する工程
工程２：該接着層付基材の上に、プリント配線板（２）又はプリント回路板（２）を積層し、加熱及び加圧下に圧着する工程 The following items are provided by this disclosure.
(Item 1A)
An adhesive comprising a high softening point polyimide having a softening point of 140° C. or higher, a low softening point polyimide having a softening point of 100° C. or lower, and a cross-linking agent.
(Item 1B)
The adhesive according to the above items, containing an organic solvent.
(Item 1)
An adhesive comprising a high softening point polyimide having a softening point of 140° C. or higher, a low softening point polyimide having a softening point of 100° C. or lower, a cross-linking agent and an organic solvent.
(Item 2)
The adhesive according to the above items, comprising two or more of the low softening point polyimides.
(Item 3)
The adhesive according to any one of the above items, wherein the low softening point polyimide is 65 to 400 parts by mass with respect to 100 parts by mass (solid content conversion) of the high softening point polyimide.
(Item 4)
The adhesive according to any one of the above items, wherein the cross-linking agent is at least one selected from the group consisting of epoxides, benzoxazines, bismaleimides and cyanate esters.
(Item 5)
The epoxide has the following structure

(In the formula, Y represents a phenylene group or a cyclohexylene group.)
The adhesive according to any one of the preceding items, which is an epoxide of
(Item 6)
Any one of the above items, which contains 5 to 900 parts by mass of a cross-linking agent and 150 to 900 parts by mass of an organic solvent for a total of 100 parts by mass of high softening point polyimide and low softening point polyimide (in terms of solid content) Adhesive as described.
(Item 7)
A film-like adhesive comprising a heat-cured product of the adhesive according to any one of the above items.
(Item 8)
An adhesive layer comprising the adhesive according to any one of the above items or the film adhesive of the above items.
(Item 9)
An adhesive sheet comprising the adhesive layer and the support film according to the above items.
(Item 10)
A resin-coated copper foil comprising the adhesive layer and the copper foil as described above.
(Item 11)
A copper-clad laminate comprising the resin-coated copper foil and the copper foil as described above.
(Item 12)
A copper-clad laminate comprising the resin-coated copper foil and the insulating sheet according to the above items.
(Item 13)
A printed wiring board having a circuit pattern on the copper foil surface of the copper-clad laminate according to any one of the above items.
(Item 14)
printed wiring board (1) or printed circuit board (1),
The adhesive layer according to the above items, and a printed wiring board (2) or a printed circuit board (2),
Multilayer wiring board.
(Item 15)
A method for manufacturing a multilayer wiring board including the following steps 1 and 2.
Step 1: Bonding by contacting at least one surface of the printed wiring board (1) or the printed circuit board (1) with the adhesive according to any one of the above items or the film adhesive according to the above items. Process for producing a layered base material Step 2: A step of laminating a printed wiring board (2) or a printed circuit board (2) on the base material with an adhesive layer and crimping under heat and pressure.

In the present disclosure, one or more of the features described above may be provided in further combinations in addition to the explicit combinations.

By using the adhesive of the present invention, it is possible to provide an adhesive layer having excellent room-temperature adhesion, solder heat resistance in a moisture-absorbing state (hygroscopic solder heat resistance), and low dielectric properties. The adhesive can be suitably used for high-frequency electronic components such as printed wiring boards and other high-performance mobile terminals.

Throughout the present disclosure, the range of numerical values for each physical property value, content, etc. can be set as appropriate (for example, by selecting from the upper and lower limit values described in each item below). Specifically, for the numerical value α, when the upper limit of the numerical value α is A1, A2, A3, etc., and the lower limit of the numerical value α is B1, B2, B3, etc., the range of the numerical value α is A1 or less, A2 or less, A3 or less, B1 or more, B2 or more, B3 or more, A1-B1, A1-B2, A1-B3, A2-B1, A2-B2, A2-B3, A3-B1, A3-B2, A3-B3 etc. are exemplified.

[glue]
The present disclosure provides an adhesive comprising a high softening point polyimide with a softening point of 140° C. or higher, a low softening point polyimide with a softening point of 100° C. or lower, and a cross-linking agent. In one embodiment, the adhesive may contain an organic solvent, which will be described later.

<Polyimide>
High softening point polyimide and low softening point polyimide may be collectively referred to as polyimide.
In one embodiment, polyimides are reactants of a group of monomers including aromatic tetracarboxylic anhydrides and diamines.

(Aromatic tetracarboxylic anhydride)
Aromatic tetracarboxylic anhydrides may be used alone or in combination of two or more. Examples of aromatic tetracarboxylic anhydrides include symmetrical aromatic tetracarboxylic anhydrides.

（式中、Ｘは単結合、－ＳＯ_２－、－ＣＯ－、－Ｏ－、－Ｏ－Ｃ_６Ｈ_４－Ｃ（ＣＨ_３）_２－Ｃ_６Ｈ_４－Ｏ－、－ＣＯＯ－（ＣＨ_２）_ｐ－ＯＣＯ－、又は－ＣＯＯ－Ｈ_２Ｃ－ＨＣ（－Ｏ－Ｃ（＝Ｏ）－ＣＨ_３）－ＣＨ_２－ＯＣＯ－を表し、ｐは１～２０の整数を表す。）
で示されるもの等が例示される。 (symmetrical aromatic tetracarboxylic anhydride)
In the present disclosure, "symmetrical aromatic tetracarboxylic anhydride" means an aromatic tetracarboxylic anhydride having a symmetry axis (eg, C2 symmetry axis) in the molecule. The symmetrical aromatic tetracarboxylic anhydride has the following general formula

(Wherein, X is a single bond, —SO ₂ —, —CO—, —O—, —O—C ₆ H ₄ —C(CH ₃ ) ₂ —C ₆ H ₄ —O—, —COO—(CH ₂ ) _p -OCO- or -COO-H ₂ C-HC(-OC(=O)-CH ₃ )-CH ₂ -OCO-, p represents an integer of 1 to 20.)
and the like are exemplified.

The symmetrical aromatic tetracarboxylic anhydride represented by the above general formula includes 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, anhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, 3,3′,4,4′-diphenyl ether tetracarboxylic dianhydride, 4,4′-[propane-2,2 -diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, 2,2-bis(3,3′,4,4′-tetracarboxyphenyl)tetrafluoropropane dianhydride, 2,2-bis( 3,4-dicarboxyphenyl)propane dianhydride, 2,2′-bis(3,4-dicarboxyphenoxyphenyl)sulfone dianhydride, 2,2′,3,3′-biphenyltetracarboxylic dianhydride 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, pyromellitic dianhydride, 1,2,3,4-benzenetetracarboxylic anhydride, 1,4,5,8 -naphthalenetetracarboxylic anhydride, 2,3,6,7-naphthalenetetracarboxylic anhydride, and the like.

Among the above symmetrical aromatic tetracarboxylic anhydrides, 3,3′,4,4′-benzophenonetetra selected from the group consisting of carboxylic dianhydride, 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, and 4,4'-oxydiphthalic anhydride At least one is preferred.

The upper limit of the content of the symmetrical aromatic tetracarboxylic anhydride in 100 mol% of the aromatic tetracarboxylic anhydride is 100, 90, 80, 70, 60, 55, 50, 40, 30, 20, 10 mol% etc., and the lower limit is exemplified by 95, 90, 80, 70, 60, 50, 40, 30, 20, 10, 0 mol %. In one embodiment, the content of the symmetrical aromatic tetracarboxylic anhydride in 100 mol % of the aromatic tetracarboxylic anhydride is preferably about 50 to 100 mol %.

The upper limit of the content of the symmetrical aromatic tetracarboxylic anhydride in 100% by mass of the aromatic tetracarboxylic anhydride is 100, 90, 80, 70, 60, 55, 50, 40, 30, 20, 10% by mass. etc., and the lower limit is exemplified by 95, 90, 80, 70, 60, 50, 40, 30, 20, 10, 0% by mass, and the like. In one embodiment, the content of the symmetrical aromatic tetracarboxylic anhydride in 100% by mass of the aromatic tetracarboxylic anhydride is preferably about 0 to 100% by mass, more preferably about 50 to 100% by mass.

The upper limit of the content of the symmetrical aromatic tetracarboxylic acid anhydride in 100 mol% of the monomer group is exemplified by 75, 70, 60, 50, 40, 30, 20, 10, 5 mol%, etc., and the lower limit is 70 , 60, 50, 40, 30, 20, 10, 5, 0 mol %, and the like. In one embodiment, the content of the symmetrical aromatic tetracarboxylic anhydride in 100 mol % of the monomer group is preferably about 0 to 75 mol %.

The upper limit of the content of the symmetrical aromatic tetracarboxylic anhydride in 100% by mass of the monomer group is exemplified by 75, 70, 60, 50, 40, 30, 20, 10, 5% by mass, etc., and the lower limit is 70. , 60, 50, 40, 30, 20, 10, 5, 0% by mass, and the like. In one embodiment, the content of the symmetrical aromatic tetracarboxylic acid anhydride in 100% by mass of the monomer group is preferably about 0 to 75% by mass.

(Other aromatic tetracarboxylic anhydrides)
In one embodiment, the monomer group can include aromatic tetracarboxylic anhydrides (also referred to as other aromatic tetracarboxylic anhydrides) that are not symmetrical aromatic tetracarboxylic anhydrides.

In one embodiment, the content of the other acid anhydride in the aromatic tetracarboxylic acid anhydride is less than 5, 4, 1, 0.9, 0.5, 0.1 mol%, about 0 mol% etc. are exemplified.

In one embodiment, the content of the other acid anhydride in the aromatic tetracarboxylic acid anhydride is less than 5, 4, 1, 0.9, 0.5, 0.1 mass%, about 0 mass% etc. are exemplified.

In one embodiment, the content of other acid anhydrides in the monomer group is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1 mol%, and about 0 mol%. .

In one embodiment, the content of other acid anhydrides in the monomer group is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1% by mass, about 0% by mass, and the like. .

The upper limit of the content of the aromatic tetracarboxylic anhydride in 100 mol% of the monomer group is exemplified by 75, 70, 65, 60, 55 mol%, and the lower limit is 70, 65, 60, 55, 50 mol. % etc. are exemplified. In one embodiment, the content of the aromatic tetracarboxylic acid anhydride in 100 mol % of the monomer group is preferably about 50 to 75 mol %.

The upper limit of the content of the aromatic tetracarboxylic acid anhydride in 100% by mass of the monomer group is exemplified by 75, 70, 65, 60, 55% by mass, etc., and the lower limit is 70, 65, 60, 55, 50% by mass. % etc. are exemplified. In one embodiment, the content of the aromatic tetracarboxylic acid anhydride in 100% by mass of the monomer group is preferably about 50 to 75% by mass.

<Diamine>
A diamine can be used individually or in 2 or more types. Diamines are exemplified by dimer diamines, alicyclic diamines, diaminopolysiloxanes and the like.

(dimer diamine)
In the present disclosure, the dimer diamine is obtained by substituting all the carboxyl groups of a dimer acid, which is a dimer of unsaturated fatty acids such as oleic acid, with primary amino groups (see JP-A-9-12712, etc.). Various known ones can be used without particular limitation. Hereinafter, non-limiting general formulas of dimer diamines are shown (in each formula, m + n = 6 to 17 is preferable, p + q = 8 to 19 is preferable, and the broken line indicates a carbon-carbon single bond or a carbon-carbon double bond. means).

Commercially available dimer diamines include Versamin 551 (manufactured by Cognix Japan Co., Ltd.), Versamin 552 (manufactured by Cognix Japan Co., Ltd.; hydrogenated Versamin 551), PRIAMINE 1075, and PRIAMINE 1074 (both manufactured by Croda Japan Co., Ltd.). ) and the like are exemplified.

The upper limit of the content of the dimer diamine component in 100 mol% of diamine is exemplified by 100, 90, 80, 70, 60, 50, 40, 30, 25 mol%, and the lower limit is 90, 80, 75, 70. , 60, 50, 40, 30, 25, 20 mol %, and the like. In one embodiment, the content of the dimer diamine component in 100 mol % of diamine is preferably about 20 to 100 mol % from the viewpoint of improving flexibility, adhesiveness and solvent solubility.

The upper limit of the content of the dimer diamine component in 100% by mass of diamine is exemplified by 100, 90, 80, 70, 60, 50, 40, 30, 25% by mass, etc., and the lower limit is 90, 80, 75, 70. , 60, 50, 40, 30, 25, 20% by mass, and the like. In one embodiment, the content of the dimer diamine component in 100% by mass of diamine is preferably about 20 to 100% by mass from the viewpoint of improving flexibility, adhesiveness and solvent solubility.

The upper limit of the content of structural units derived from dimer diamine in 100 mol% of structural units derived from diamine in the high softening point polyimide is exemplified by 50, 40, 30, 25 mol%, and the lower limit is 45, 40, 30. , 25, 20 mol % and the like are exemplified. In one embodiment, the content of structural units derived from dimer diamine in 100 mol % of diamine-derived structural units in the high softening point polyimide is preferably 20 to 50 mol %.

The upper limit of the content of structural units derived from dimer diamine in 100% by mass of structural units derived from diamine in the high softening point polyimide is exemplified by 50, 40, 30, 25% by mass, etc., and the lower limit is 45, 40, 30. , 25, 20% by mass, and the like. In one embodiment, the content of structural units derived from dimer diamine in 100% by mass of structural units derived from diamine in the high softening point polyimide is preferably 20 to 50% by mass.

The upper limit of the content of structural units derived from dimer diamine in 100 mol% of structural units derived from diamine in the low softening point polyimide is exemplified by 100, 90, 80, 70, 60 mol%, and the lower limit is 95, 90. , 80, 70, 60, 55 mol % and the like are exemplified. In one embodiment, the content of structural units derived from dimer diamine in 100 mol % of diamine-derived structural units in the low softening point polyimide is preferably 55 to 100 mol %.

The upper limit of the content of structural units derived from dimer diamine in 100% by mass of structural units derived from diamine in the low softening point polyimide is exemplified by 100, 90, 80, 70, 60% by mass, etc., and the lower limit is 95, 90. , 80, 70, 60, 55% by mass, and the like. In one embodiment, the content of structural units derived from dimer diamine in 100% by mass of structural units derived from diamine in the low softening point polyimide is preferably 55 to 100% by mass.

(alicyclic diamine)
Cycloaliphatic diamines include diaminocyclohexane, diaminodicyclohexylmethane, dimethyl-diaminodicyclohexylmethane, diaminobicyclo[2.2.1]heptane, bis(aminomethyl)-bicyclo[2.2.1]heptane, 3(4) , 8(9)-bis(aminomethyl)tricyclo[5.2.1.02,6]decane, isophoronediamine, 4,4'-diaminodicyclohexylmethane, 1,3-bisaminomethylcyclohexane and the like. .

One example of a method of adjusting the softening point of polyimide is a method of adjusting the amount of alicyclic diamine in diamine. As the amount of alicyclic diamine in the diamine increases, the softening point of the polyimide increases. The above adjustment example is just one example, and various known methods can be used to adjust the softening point of polyimide.

The upper limit of the content of the structural unit derived from the alicyclic diamine in the high softening point polyimide is exemplified by 80, 70, 60, 50 mol%, etc., and the lower limit is 75, 70, 60, 50, 45 mol%, etc. are exemplified. In one embodiment, when producing a high softening point polyimide, it is preferable to include 45 to 80 mol % of an alicyclic diamine in the diamine.

The upper limit of the content of the structural unit derived from the alicyclic diamine in the low softening point polyimide is exemplified by 40, 30, 20, 10, 5 mol%, and the lower limit is 35, 30, 20, 10, 5, 0 mol % and the like are exemplified. In one embodiment, when producing a low softening point polyimide, it is preferable to include 0 to 40 mol % of an alicyclic diamine in the diamine.

When producing a polyimide having a high softening point, the upper limit of the substance amount ratio of dimer diamine and alicyclic diamine (dimer diamine/alicyclic diamine) is 1.3, 1.0, 0.5, 0.5, 0.5, 1.0, 1.0, 1.0, 0.5, 0.5, 1.0, 1.0, 1.0, 1.0, 1.0, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5 and 0.5. 3 and the like are exemplified, and the lower limits are exemplified by 1.2, 1.0, 0.5, 0.3, 0.2 and the like. In one embodiment, when producing a polyimide with a high softening point, the substance amount ratio of dimer diamine and alicyclic diamine (dimer diamine/alicyclic diamine) is preferably 0.2 to 1.3.

In one embodiment, when producing a low softening point polyimide, the substance amount ratio of dimer diamine and alicyclic diamine (dimer diamine/alicyclic diamine) is 1.4 or more (for example, 2 or more, 5 or more , 10 or more, 100 or more).

(Diaminopolysiloxane)
Diaminopolysiloxane includes α,ω-bis(2-aminoethyl)polydimethylsiloxane, α,ω-bis(3-aminopropyl)polydimethylsiloxane, α,ω-bis(4-aminobutyl)polydimethylsiloxane, α,ω-bis(5-aminopentyl)polydimethylsiloxane, α,ω-bis[3-(2-aminophenyl)propyl]polydimethylsiloxane, α,ω-bis[3-(4-aminophenyl)propyl ] polydimethylsiloxane, 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 1,3-bis(4-aminobutyl)tetramethyldisiloxane and the like.

The upper limit of the content of diaminopolysiloxane in 100 mol% of diamine is exemplified by 5, 4, 3, 2, 1 mol%, etc., and the lower limit is exemplified by 4, 3, 2, 1, 0 mol%, etc. be. In one embodiment, the content of diaminopolysiloxane in 100 mol % of diamine is preferably about 0 to 5 mol % from the viewpoint of improving flexibility.

The upper limit of the content of diaminopolysiloxane in 100% by mass of diamine is exemplified by 5, 4, 3, 2, 1% by mass, etc., and the lower limit is exemplified by 4, 3, 2, 1, 0% by mass, etc. be. In one embodiment, the content of diaminopolysiloxane in 100% by mass of diamine is preferably about 0 to 5% by mass from the viewpoint of improving flexibility.

(other diamines)
Diamines other than the above include bisaminophenoxyphenylpropane, diaminodiphenylether, phenylenediamine, diaminodiphenylsulfide, diaminodiphenylsulfone, diaminobenzophenone, diaminodiphenylmethane, diaminophenylpropane, diaminophenylhexafluoropropane, diaminophenylphenylethane, bisaminophenoxy Benzene, bisaminobenzoylbenzene, bisaminodimethylbenzylbenzene, bisaminoditrifluoromethylbenzylbenzene, aminophenoxybiphenyl, aminophenoxyphenyl ketone, aminophenoxyphenyl sulfide, aminophenoxyphenyl sulfone, aminophenoxyphenyl ether, aminophenoxyphenylpropane, Bis(aminophenoxybenzoyl)benzene, bis(aminophenoxy-α,α-dimethylbenzyl)benzene, bis[(aminoaryloxy)benzoyl]diphenyl ether, bis(amino-α,α-dimethylbenzylphenoxy)benzophenone, bis[amino -α,α-dimethylbenzylphenoxy]diphenylsulfone, 4,4′-bis[aminophenoxyphenoxy]diphenylsulfone, diaminodiaryloxybenzophenone, diaminoaryloxybenzophenone, 6,6′-bis(aminoaryloxy)3,3 , 3,'3,'-tetramethyl-1,1'-spirobiindane, bis(aminoalkyl)ether, bis(aminoalkoxyalkyl)ether, bis(aminoalkoxy)alkane, bis[(aminoalkoxy)alkoxy]alkane, (Poly)ethylene glycol bis(aminoalkyl)ether, bis(aminoaryloxy)pyridine, diaminoalkylene and the like are exemplified.

Bisaminophenoxyphenylpropane is exemplified by 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane and the like.

Diaminodiphenyl ether is exemplified by 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether and the like.

Phenylenediamine is exemplified by phenylenediamine such as p-phenylenediamine and m-phenylenediamine.

Diaminodiphenyl sulfide is exemplified by 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide and the like.

Diaminodiphenyl sulfone is exemplified by 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone and the like.

Diaminobenzophenone is exemplified by 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone and the like.

Diaminodiphenylmethane is exemplified by 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane and the like.

Diaminophenylpropane includes 2,2-di(3-aminophenyl)propane, 2,2-di(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-aminophenyl)propane and the like. are exemplified.

Diaminophenylhexafluoropropane is 2,2-di(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-di(4-aminophenyl)-1,1 , 1,3,3,3-hexafluoropropane, 2-(3-aminophenyl)-2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane and the like. be.

Diaminophenylphenylethane is 1,1-di(3-aminophenyl)-1-phenylethane, 1,1-di(4-aminophenyl)-1-phenylethane, 1-(3-aminophenyl)-1 -(4-aminophenyl)-1-phenylethane and the like are exemplified.

Bisaminophenoxybenzene includes 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,4-bis (4-aminophenoxy)benzene and the like are exemplified.

Bisaminobenzoylbenzene is 1,3-bis(3-aminobenzoyl)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,4-bis(3-aminobenzoyl)benzene, 1,4-bis (4-aminobenzoyl)benzene and the like are exemplified.

Bisaminodimethylbenzylbenzene is 1,3-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,4-bis Examples include (3-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene and the like.

Bisaminoditrifluoromethylbenzylbenzene is 1,3-bis(3-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,3-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene , 1,4-bis(3-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,4-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene and the like.

Aminophenoxybiphenyl is exemplified by 2,6-bis(3-aminophenoxy)benzonitrile, 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl and the like. be.

Aminophenoxyphenyl ketone is exemplified by bis[4-(3-aminophenoxy)phenyl]ketone, bis[4-(4-aminophenoxy)phenyl]ketone and the like.

Aminophenoxyphenyl sulfide is exemplified by bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-(4-aminophenoxy)phenyl]sulfide and the like.

Aminophenoxyphenyl sulfone is exemplified by bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone and the like.

Aminophenoxyphenyl ether is exemplified by bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl]ether and the like.

Aminophenoxyphenylpropane is 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3 ,3-hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane and the like.

Bis(aminophenoxybenzoyl)benzene is 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,4-bis Examples include [4-(3-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzoyl]benzene and the like.

Bis(aminophenoxy-α,α-dimethylbenzyl)benzene is 1,3-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4- aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis[4-(4-aminophenoxy )-α,α-dimethylbenzyl]benzene and the like.

Bis[(aminoaryloxy)benzoyl]diphenyl ether is exemplified by 4,4'-bis[4-(4-aminophenoxy)benzoyl]diphenyl ether.

Bis(amino-α,α-dimethylbenzylphenoxy)benzophenone is exemplified by 4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzophenone and the like.

Bis[amino-α,α-dimethylbenzylphenoxy]diphenylsulfone is
4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylsulfone and the like are exemplified.

4,4'-bis[aminophenoxyphenoxy]diphenylsulfone is exemplified by 4,4'-bis[4-(4-aminophenoxy)phenoxy]diphenylsulfone.

Diaminodiaryloxybenzophenone is exemplified by 3,3'-diamino-4,4'-diphenoxybenzophenone, 3,3'-diamino-4,4'-dibiphenoxybenzophenone and the like.

Diaminoaryloxybenzophenone is exemplified by 3,3'-diamino-4-phenoxybenzophenone, 3,3'-diamino-4-biphenoxybenzophenone and the like.

6,6'-bis(aminoaryloxy)-3,3,3',3'-tetramethyl-1,1'-spirobiindane is 6,6'-bis(3-aminophenoxy)-3,3, 3′,3′-tetramethyl-1,1′-spirobiindane, 6,6′-bis(4-aminophenoxy)-3,3,3′,3′-tetramethyl-1,1′-spirobiindane and the like exemplified.

Bis(aminoalkyl)ethers are exemplified by bis(aminomethyl)ether, bis(2-aminoethyl)ether, bis(3-aminopropyl)ether and the like.

Bis(aminoalkoxyalkyl) ether includes bis[2-(aminomethoxy)ethyl]ether, bis[2-(2-aminoethoxy)ethyl]ether, bis[2-(3-aminoprotoxy)ethyl] Ether and the like are exemplified.

Bis(aminoalkoxy)alkanes are exemplified by 1,2-bis(aminomethoxy)ethane, 1,2-bis(2-aminoethoxy)ethane and the like.

Bis[(aminoalkoxy)alkoxy]alkanes are exemplified by 1,2-bis[2-(aminomethoxy)ethoxy]ethane, 1,2-bis[2-(2-aminoethoxy)ethoxy]ethane and the like.

(Poly)ethylene glycol bis(aminoalkyl) ether, ethylene glycol bis(3-aminopropyl) ether, diethylene glycol bis(3-aminopropyl) ether, triethylene glycol bis(3-aminopropyl) ether, etc. are exemplified.

Bis(aminoaryloxy)pyridine is exemplified by 2,6-bis(3-aminophenoxy)pyridine and the like.

Diaminoalkylene includes ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1, Examples include 9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane and the like.

In one embodiment, the content of the other diamine in the diamine is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1 mol%, about 0 mol%, and the like.

In one embodiment, the content of the other diamine in the diamine is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1% by mass, about 0% by mass, and the like.

In one embodiment, the content of other diamines in the monomer group is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1 mol %, about 0 mol %, and the like.

In one embodiment, the content of other diamines in the monomer group is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1% by mass, about 0% by mass, and the like.

The upper limit of the diamine content in 100 mol% of the monomer group is exemplified by 50, 45, 40, 35, 30 mol%, etc., and the lower limit is exemplified by 45, 40, 35, 30, 25 mol%, etc. . In one embodiment, the diamine content in 100 mol % of the monomer group is preferably about 25 to 50 mol %.

The upper limit of the diamine content in 100% by mass of the monomer group is exemplified by 50, 45, 40, 35, 30% by mass, etc., and the lower limit is exemplified by 45, 40, 35, 30, 25% by mass, etc. . In one embodiment, the diamine content in 100% by mass of the monomer group is preferably about 25 to 50% by mass.

The upper limit of the molar ratio of aromatic tetracarboxylic anhydride and diamine [aromatic tetracarboxylic anhydride/diamine] is exemplified by 1.5, 1.4, 1.3, 1.2, 1.1, etc. and the lower limit is exemplified by 1.4, 1.3, 1.2, 1.1, 1.0, and the like. In one embodiment, the molar ratio of aromatic tetracarboxylic anhydride and diamine [aromatic tetracarboxylic anhydride/diamine] is about 1.0 to 1.5 from the viewpoint of solvent solubility and solution stability. is preferred.

The upper limit of the mass ratio of the aromatic tetracarboxylic anhydride and the diamine [aromatic tetracarboxylic anhydride/diamine] is 1.5, 1.4, 1.2, 1.0, 0.9, 0.5, 1.5, 1.4, 1.2, 1.0, 0.9, 0.9. 7, 0.6, etc. are exemplified, and the lower limit is exemplified as 1.4, 1.2, 1.0, 0.9, 0.7, 0.6, 0.5, etc. In one embodiment, the mass ratio of aromatic tetracarboxylic anhydride to diamine [aromatic tetracarboxylic anhydride/diamine] is preferably 0.5 to 1.5.

<Other monomers>
In one embodiment, the monomer group can include monomers that are neither aromatic tetracarboxylic anhydrides nor diamines (also referred to as other monomers). Other monomers are exemplified by aliphatic tetracarboxylic anhydrides and the like.

In one embodiment, the content of other monomers in the monomer group is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1 mol %, about 0 mol %, and the like.

In one embodiment, the content of other monomers in the monomer group is exemplified by 5, 4, 1, 0.9, 0.5, less than 0.1% by mass, about 0% by mass, and the like.

<Physical properties of polyimide>
The upper limit of the weight average molecular weight of the polyimide is 50000, 40000, 30000, 20000, 10000, 7500, 5500 and the like, and the lower limit is 45000, 40000, 30000, 20000, 10000, 7500 and 5000. In one embodiment, the polyimide preferably has a weight average molecular weight of 5,000 to 50,000 from the viewpoint of dielectric properties, solvent solubility, and flexibility.

The upper limit of the number average molecular weight of the polyimide is exemplified by 40000, 30000, 20000, 10000, 7500, 5000, 3000 and the like, and the lower limit is exemplified by 35000, 30000, 20000, 10000, 7500, 5000, 3000 and 2000. be. In one embodiment, the polyimide preferably has a number average molecular weight of 2,000 to 40,000 from the viewpoint of dielectric properties, solvent solubility, and flexibility.

The weight-average molecular weight and number-average molecular weight can be determined, for example, as polystyrene-equivalent values measured by gel permeation chromatography (GPC).

The softening point of the high softening point polyimide is not particularly limited as long as it is 140° C. or higher. The upper limit of the softening point of the high softening point polyimide is exemplified by 220, 210, 200, 190, 180, 170, 160, 150, 145 ° C., etc., and the lower limit is 210, 200, 190, 180, 170, 160, 150. , 145, 140° C. and the like are exemplified. In one embodiment, the softening point of the high softening point polyimide is preferably 140°C or higher, more preferably 140 to 220°C.

The softening point of the low softening point polyimide is not particularly limited as long as it is 100° C. or lower. The upper limit of the softening point of the low softening point polyimide is exemplified by 100, 90, 80, 70, 60, 50, 40, 30, 25 ° C., and the lower limit is 90, 80, 70, 60, 50, 40, 30 , 25, 20° C. and the like are exemplified. In one embodiment, the softening point of the low softening point polyimide is preferably 100°C or less, more preferably 20 to 100°C.

The softening point can be obtained using a commercially available measuring instrument (“ARES-2KSTD-FCO-STD”, manufactured by Rheometric Scientific) or the like.

<Method for producing polyimide, etc.>
The above polyimide can be produced by various known methods. In the method for producing a polyimide, a group of monomers containing diamines including aromatic tetracarboxylic anhydrides and dimer diamines is preferably heated at a temperature of about 60 to 120°C, more preferably about 80 to 100°C, preferably 0. A step of conducting a polyaddition reaction for about 1 to 2 hours, more preferably about 0.1 to 0.5 hours to obtain a polyadduct, and the resulting polyadduct is preferably heated to about 80 to 250° C., more preferably is a method including a step of imidization reaction, ie dehydration ring closure reaction, at a temperature of about 100 to 200° C. for preferably about 0.5 to 50 hours, more preferably about 1 to 20 hours.

In addition, in the imidization reaction step, various known reaction catalysts, dehydrating agents, and organic solvents to be described later can be used. Various known reaction catalysts, dehydrating agents, and organic solvents described below may be used alone or in combination of two or more. Examples of reaction catalysts include aliphatic tertiary amines such as triethylamine, aromatic tertiary amines such as dimethylaniline, and heterocyclic tertiary amines such as pyridine, picoline and isoquinoline. Examples of dehydrating agents include aliphatic acid anhydrides such as acetic anhydride and aromatic acid anhydrides such as benzoic anhydride.

The imide ring closure ratio of the polyimide is not particularly limited. Here, the "imido ring closure ratio" means the content of cyclic imide bonds in polyimide, and can be determined by various spectroscopic means such as NMR and IR analysis. From the viewpoint of good room-temperature adhesion and heat-resistant adhesion, the imide ring closure ratio of the polyimide is preferably about 70% or more, more preferably about 85 to 100%.

The upper limit of the content of the high softening point polyimide in the entire polyimide is exemplified by 60, 50, 40, 30, 25% by mass, etc., and the lower limit is exemplified by 55, 50, 40, 30, 25, 20% by mass, etc. be done. In one embodiment, the content of the high softening point polyimide in the entire polyimide is preferably 20 to 60% by mass from the viewpoint of heat resistance, flexibility and adhesiveness.

The upper limit of the content of the low softening point polyimide in the entire polyimide is exemplified by 80, 70, 60, 50, 45% by mass, etc., and the lower limit is exemplified by 75, 70, 60, 50, 40% by mass, etc. . In one embodiment, the content of the low softening point polyimide in the entire polyimide is preferably 40 to 80% by mass from the viewpoint of heat resistance, flexibility and adhesion.

The upper limit of the ratio of the low softening point polyimide to 100 parts by mass of the high softening point polyimide (solid content conversion) is exemplified by 400, 300, 200, 100, 75, 70 parts by mass, etc., and the lower limit is 350, 300, 200, 100, 75, 70, 65 mass parts, etc. are illustrated. The range of the ratio can be appropriately set (for example, selected from the upper limit and lower limit values). In one embodiment, it is preferable that the low softening point polyimide is 65 to 400 parts by mass with respect to 100 parts by mass (solid content conversion) of the high softening point polyimide.

In one embodiment, two or more kinds of low softening point polyimides are included in the polyimide.

The upper limit of the content of the polyimide in 100% by mass of the adhesive is exemplified by 90, 80, 70, 60, 50, 40, 30, 20, 10% by mass, etc., and the lower limit is 80, 70, 60, 50% by mass. , 40, 30, 20, 10, 5% by mass, and the like. The content of the polyimide in 100% by mass of the adhesive is preferably about 5 to 90% by mass.

<Crosslinking agent>
Various known cross-linking agents can be used without particular limitation as long as they function as cross-linking agents for polyimide. Cross-linking agents may be used alone or in combination of two or more. The cross-linking agent is preferably at least one selected from the group consisting of epoxides, benzoxazines, bismaleimides and cyanate esters.

(epoxide)
Epoxides include phenol novolac type epoxide, cresol novolac type epoxide, bisphenol A type epoxide, bisphenol F type epoxide, bisphenol S type epoxide, hydrogenated bisphenol A type epoxide, hydrogenated bisphenol F type epoxide, stilbene type epoxide, and triazine skeleton-containing epoxide. , fluorene skeleton-containing epoxide, linear aliphatic epoxide, alicyclic epoxide, glycidylamine-type epoxide, triphenolmethane-type epoxide, alkyl-modified triphenolmethane-type epoxide, biphenyl-type epoxide, dicyclopentadiene skeleton-containing epoxide, naphthalene skeleton-containing Examples include epoxides, arylalkylene-type epoxides, tetraglycidylxylylenediamine, dimer acid-modified epoxides which are dimer acid-modified epoxides, dimer acid diglycidyl esters, and the like. In addition, commercially available epoxides include "jER828", "jER834", and "jER807" manufactured by Mitsubishi Chemical Corporation, "ST-3000" manufactured by Nippon Steel Chemical Co., Ltd., and manufactured by Daicel Chemical Industries, Ltd. Examples include “Celoxide 2021P”, “YD-172-X75” manufactured by Nippon Steel Chemical Co., Ltd., and “TETRAD-X” manufactured by Mitsubishi Gas Chemical Co., Ltd. Among these, at least one selected from the group consisting of bisphenol A type epoxides, bisphenol F type epoxides, hydrogenated bisphenol A type epoxides and alicyclic epoxides from the viewpoint of the balance of heat-resistant adhesiveness, moisture absorption solder heat resistance and low dielectric properties. Seeds are preferred.

（式中、Ｙはフェニレン基又はシクロヘキシレン基を表す。）
は、上記ポリイミドとの相溶性が良好である。また、これを用いると接着層の低損失弾性率化が容易となり、その耐熱接着性及び低誘電特性も良好となる。 In particular, tetraglycidyldiamine of the structure

(In the formula, Y represents a phenylene group or a cyclohexylene group.)
has good compatibility with the polyimide. In addition, the use of this makes it easy to reduce the loss elastic modulus of the adhesive layer, and the heat-resistant adhesiveness and low dielectric properties of the adhesive layer are also improved.

When an epoxide is used as the cross-linking agent, various known epoxide curing agents can be used in combination. Epoxide curing agents may be used alone or in combination of two or more. Curing agents for epoxides include succinic anhydride, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride. , or a mixture of 4-methyl-hexahydrophthalic anhydride and hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl-tetrahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, norbornane-2,3-dicarboxylic anhydride , methylnorbornane-2,3-dicarboxylic anhydride, methylcyclohexenedicarboxylic anhydride, 3-dodecenylsuccinic anhydride, octenylsuccinic anhydride, etc.; Names "Lonzacure M-DEA", "Lonzacure M-DETDA", etc., both manufactured by Lonza Japan Co., Ltd.), amine-based curing agents such as aliphatic amines; Phenolic curing agents such as phenolic novolac resins, phenolic hydroxyl group-containing phosphazenes (trade name "SPH-100" manufactured by Otsuka Chemical Co., Ltd., etc.), cyclic phosphazene compounds, rosins such as maleic acid-modified rosin and its hydrides A cross-linking agent and the like are exemplified. Among these, phenol-based curing agents, particularly phenolic hydroxyl group-containing phosphazene-based curing agents are preferred. The amount of the curing agent used is not particularly limited, but is preferably about 0.1 to 120% by mass, more preferably about 10 to 40% by mass, when the solid content of the adhesive is 100% by mass.

When an epoxide and a curing agent for epoxide are used together as a cross-linking agent, a reaction catalyst can be further used together. A reaction catalyst may be used alone or in combination of two or more. The reaction catalyst is a tertiary amine such as 1,8-diaza-bicyclo[5.4.0]undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol; imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole and 2-heptadecylimidazole; organic compounds such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine and phenylphosphine Phosphine; Tetraphenylboron salts such as tetraphenylphosphonium/tetraphenylborate, 2-ethyl-4-methylimidazole/tetraphenylborate, N-methylmorpholine/tetraphenylborate, and the like are exemplified. The amount of the reaction catalyst used is not particularly limited, but is preferably about 0.01 to 5% by mass when the solid content of the adhesive is 100% by mass.

(benzoxazine)
Benzoxazines are 6,6-(1-methylethylidene)bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine), 6,6-(1-methylethylidene)bis(3, 4-dihydro-3-methyl-2H-1,3-benzoxazine) and the like. A phenyl group, a methyl group, a cyclohexyl group, or the like may be bonded to the nitrogen of the oxazine ring. In addition, commercial products of benzoxazine include "Benzoxazine Fa type" and "Benzoxazine Pd type" manufactured by Shikoku Kasei Co., Ltd., and "RLV-100" manufactured by Air Water. etc. are exemplified.

(bismaleimide)
Bismaleimides include 4,4′-diphenylmethanebismaleimide, m-phenylenebismaleimide, bisphenol A diphenylether bismaleimide, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethanebismaleimide, 4- Examples include methyl-1,3-phenylenebismaleimide, 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, 4,4'-diphenyletherbismaleimide, 4,4'-diphenylsulfonebismaleimide, and the like. be done. Commercially available products of bismaleimide are exemplified by "BAF-BMI" manufactured by JFE Chemical Co., Ltd., and the like.

(cyanate ester)
Cyanate esters include 2-allylphenol cyanate ester, 4-methoxyphenol cyanate ester, 2,2-bis(4-cyanatophenol)-1,1,1,3,3,3-hexafluoropropane, bisphenol A cyanate ester, diallyl bisphenol A cyanate ester, 4-phenylphenol cyanate ester, 1,1,1-tris(4-cyanatophenyl) ethane, 4-cumylphenol cyanate ester, 1,1-bis(4-cyanatophenyl ) ethane, 4,4′-bisphenolcyanate ester, and 2,2-bis(4-cyanatophenyl)propane. Examples of commercially available cyanate esters include "PRIMASET BTP-6020S (manufactured by Lonza Japan Co., Ltd.)".

In the adhesive, the upper limit of the content of the cross-linking agent relative to 100 parts by mass of the polyimide (in terms of solid content) is 900, 800, 700, 600, 500, 400, 300, 200, 100, 50, 20, 10 parts by mass. etc., and the lower limit is exemplified by 800, 700, 600, 500, 400, 300, 200, 100, 50, 20, 10, 5 parts by mass, and the like. In one embodiment, the content of the cross-linking agent is preferably about 5 to 900 parts by mass with respect to 100 parts by mass (in terms of solid content) of the polyimide.

The upper limit of the content of the cross-linking agent in 100% by mass of the adhesive is exemplified by 80, 70, 60, 50, 40, 30, 20, 10, 5% by mass, etc., and the lower limit is 70, 60, 50, 40, 30, 20, 10, 5, 2% by mass and the like are exemplified. In one embodiment, the content of the cross-linking agent in 100% by mass of the adhesive is preferably about 2 to 80% by mass.

<Organic solvent>
As the organic solvent, various known organic solvents can be used singly or in combination of two or more. Organic solvents include aprotic polar solvents such as N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide, N-methylcaprolactam, methyltriglyme and methyldiglyme, and alicyclic solvents such as cyclohexanone and methylcyclohexane. alcoholic solvents such as methanol, ethanol, propanol, benzyl alcohol and cresol; and aromatic solvents such as toluene.

Also, the content of the organic solvent in the adhesive is not particularly limited, but the amount is preferably such that the solid content is 10 to 60% by mass with respect to 100% by mass of the adhesive.

The upper limit of the content of the organic solvent in the adhesive with respect to 100 parts by mass of the polyimide (in terms of solid content) is exemplified by 900, 800, 700, 600, 500, 400, 300, 200 parts by mass, etc., and the lower limit is 800, 700, 600, 500, 400, 300, 200, 150 mass parts, etc. are illustrated. In one embodiment, the content of the organic solvent in the adhesive is preferably 150 to 900 parts by mass with respect to 100 parts by mass (in terms of solid content) of the polyimide.

<Flame retardant>
In one embodiment, the adhesive includes a flame retardant. A flame retardant can be used individually or in 2 or more types. Flame retardants are exemplified by phosphorus-based flame retardants, inorganic fillers, and the like.

(Phosphorus-based flame retardant (phosphorus-containing flame retardant))
Phosphorus-based flame retardants are exemplified by polyphosphoric acid, phosphate esters, phosphazene derivatives containing no phenolic hydroxyl group, and the like. Among the phosphazene derivatives, cyclic phosphazene derivatives are preferred in terms of flame retardancy, heat resistance, bleed-out resistance and the like. Examples of commercial products of cyclic phosphazene derivatives include SPB-100 manufactured by Otsuka Chemical Co., Ltd. and Labitol FP-300B manufactured by Fushimi Pharmaceutical Co., Ltd.

(Inorganic filler)
In one embodiment, inorganic fillers are exemplified by silica fillers, phosphorus-based fillers, fluorine-based fillers, inorganic ion exchanger fillers, and the like. Examples of commercially available products include FB-3SDC manufactured by Denka Co., Ltd., Exolit OP935 manufactured by Clariant Chemicals Co., Ltd., KTL-500F manufactured by Kitamura Co., Ltd., IXE manufactured by Toagosei Co., Ltd., and the like.

The upper limit of the content of the flame retardant with respect to 100 parts by mass (solid content conversion) of the polyimide in the adhesive is exemplified by 150, 100, 50, 10, 5 parts by mass, etc., and the lower limit is 125, 100, 50, 10. , 5, 1 part by mass, etc. are exemplified. In one embodiment, the content of the flame retardant is preferably 1 to 150 parts by mass with respect to 100 parts by mass (in terms of solid content) of the polyimide in the adhesive.

<Reactive alkoxysilyl compound>
In one embodiment, the adhesive further has the general formula: Z—Si(R ¹ ) _a (OR ² ) _3-a (where Z is a group containing a functional group that reacts with an acid anhydride group). , R ¹ is hydrogen or a hydrocarbon group having 1 to 8 carbon atoms, R ² is a hydrocarbon group having 1 to 8 carbon atoms, and a is 0, 1 or 2.). compounds are included. Reactive alkoxysilyl compounds allow the melt viscosity of adhesive layers of the adhesives of the present invention to be adjusted while maintaining low dielectric properties. As a result, it is possible to suppress the exudation of the hardened layer from the edges of the substrate while enhancing the interfacial adhesive strength (so-called anchor effect) between the adhesive layer and the substrate.

Examples of the reactive functional group contained in Z in the above general formula include an amino group, an epoxy group and a thiol group.

Compounds in which Z contains an amino group include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and 3-aminopropyltrimethoxysilane. , 3-aminopropyltriethoxysilane and 3-ureidopropyltrialkoxysilane. Examples of compounds in which Z contains an epoxy group include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, Examples include sidoxypropylmethyldiethoxysilane and 3-glycidoxypropyltriethoxysilane. Examples of compounds in which Z contains a thiol group include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropylmethyldiethoxysilane. . Among these, a compound in which Z contains an amino group is preferable because of good reactivity and flow control effect.

The upper limit of the content of the reactive alkoxysilyl compound with respect to 100 parts by mass (solid content conversion) of the polyimide in the adhesive is 5, 2.5, 1, 0.5, 0.1, 0.05 parts by mass, etc. The lower limit is exemplified by 4, 2.5, 1, 0.5, 0.1, 0.05, 0.01 parts by mass. In one embodiment, the content of the reactive alkoxysilyl compound is preferably 0.01 to 5 parts by mass with respect to 100 parts by mass (in terms of solid content) of the polyimide in the adhesive.

The adhesive may contain an additive other than the polyimide, cross-linking agent, organic solvent, flame retardant, and reactive alkoxysilyl compound.

Additives include ring-opening esterification reaction catalysts, dehydrating agents, plasticizers, weathering agents, antioxidants, heat stabilizers, lubricants, antistatic agents, brighteners, coloring agents, conductive agents, release agents, and surface treatment. agents, viscosity modifiers, silica fillers, fluorine fillers, and the like.

In one embodiment, the content of the additive is exemplified by less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, and 0 part by mass with respect to 100 parts by mass of the adhesive.

In another embodiment, the content of the additive is less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, and 0 part by mass with respect to 100 parts by mass of the polyimide (in terms of solid content). be done.

The adhesive can be obtained by dissolving the polyimide, the cross-linking agent, and optionally the flame retardant, reactive alkoxysilyl compound, and additives in an organic solvent.

[Film adhesive]
The present disclosure provides a film adhesive containing a heat-cured product of the above adhesive. A method for producing a film-like adhesive includes a step of applying the adhesive to a suitable support, a step of heating to volatilize the organic solvent to cure the adhesive, and a step of peeling from the support. exemplified. Although the thickness of the adhesive is not particularly limited, it is preferably about 3 to 40 μm. Examples of the support include the following.

[Adhesion layer]
The present disclosure provides an adhesive layer comprising an adhesive or the film adhesive described above. When producing the adhesive layer, the above adhesive and various known adhesives other than the above adhesive may be used in combination. Similarly, the film-like adhesive and various known film-like adhesives other than the film-like adhesive may be used in combination.

[Adhesive sheet]
The present disclosure provides an adhesive sheet including the above adhesive layer and a support film.

The support film is exemplified by a plastic film. Plastics include polyester, polyimide, polyimide-silica hybrid, polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polymethyl methacrylate resin, polystyrene resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin, ethylene terephthalate, phenol, phthalic acid, Aromatic polyester resins obtained from hydroxynaphthoic acid or the like and parahydroxybenzoic acid (so-called liquid crystal polymer; "Vecstar" manufactured by Kuraray Co., Ltd., etc.) are exemplified.

Moreover, when applying the above-mentioned adhesive to the support film, the above-mentioned coating means can be employed. The thickness of the coating layer is also not particularly limited, but the thickness after drying is preferably about 1 to 100 μm, more preferably about 3 to 50 μm. Moreover, the adhesive layer of the adhesive sheet may be protected with various protective films.

[Resin coated copper foil]
The present disclosure provides a resin-coated copper foil including the adhesive layer and the copper foil. Specifically, the resin-coated copper foil is obtained by coating or pasting the adhesive or the film adhesive onto a copper foil. Examples of the copper foil include rolled copper foil and electrolytic copper foil. The thickness is not particularly limited, and is preferably about 1 to 100 μm, more preferably about 2 to 38 μm. Moreover, the copper foil may be subjected to various surface treatments (roughening, rust prevention, etc.). Examples of the antirust treatment include plating using a plating solution containing Ni, Zn, Sn, etc., and so-called mirror surface treatment such as chromate treatment. Moreover, the above-mentioned method is illustrated as a coating means.

Moreover, the adhesive layer of the resin-coated copper foil may be uncured, or partially cured or completely cured under heating. The partially cured adhesive layer is in a so-called B-stage state. Also, the thickness of the adhesive layer is not particularly limited, and is preferably about 0.5 to 30 μm. Further, a copper foil can be attached to the adhesion surface of the resin-coated copper foil to form a resin-coated copper foil on both sides.

[Copper clad laminate]
The present disclosure provides a copper-clad laminate comprising the resin-coated copper foil and the copper foil or insulating sheet. The copper clad laminate is also called CCL (Copper Clad Laminate). Specifically, the copper-clad laminate is obtained by crimping the resin-coated copper foil to at least one side or both sides of various known copper foils or insulating sheets under heating. In the case of lamination on one side, a material different from the resin-coated copper foil may be pressure-bonded to the other side. Moreover, the numbers of resin-coated copper foils and insulating sheets in the copper-clad laminate are not particularly limited.

In one embodiment, the insulating sheet is preferably prepreg. A prepreg is a sheet-shaped material obtained by impregnating a reinforcing material such as glass cloth with a resin and curing it to the B stage (JIS C 5603). Insulating resins such as polyimide resins, phenol resins, epoxy resins, polyester resins, liquid crystal polymers, and aramid resins are used as the resins. The thickness of the prepreg is not particularly limited, and is preferably about 20-500 μm. The heating/pressing conditions are not particularly limited, and are preferably about 150 to 280° C. (more preferably about 170 to 240° C.) and preferably about 0.5 to 20 MPa (more preferably about 1 to 8 MPa).

[Printed wiring board]
The present disclosure provides a printed wiring board having a circuit pattern on the copper foil surface of the copper clad laminate. Examples of patterning means for forming a circuit pattern on the copper foil surface of the copper-clad laminate include a subtractive method and a semi-additive method. The semi-additive method is exemplified by a method of patterning a copper foil surface of a copper-clad laminate with a resist film, performing electrolytic copper plating, removing the resist, and etching with an alkaline solution. Moreover, the thickness of the circuit pattern layer in the printed wiring board is not particularly limited. A multilayer board can also be obtained by using the printed wiring board as a core substrate and laminating the same printed wiring board or other known printed wiring board or printed circuit board thereon. At the time of lamination, the above-mentioned adhesives and other known adhesives other than the above-mentioned adhesives can be used together. Also, the number of laminations in the multilayer substrate is not particularly limited. Also, each time lamination is performed, a via hole may be inserted and the inside thereof may be plated. Although the line/space ratio of the circuit pattern is not particularly limited, it is preferably about 1 μm/1 μm to 100 μm/100 μm. Also, the height of the circuit pattern is not particularly limited, but is preferably about 1 to 50 μm.

[Multilayer wiring board]
The present disclosure provides a multilayer wiring board comprising a printed wiring board (1) or printed circuit board (1), the adhesive layer described above, and a printed wiring board (2) or printed circuit board (2). The printed wiring boards (1) and (2) may be the printed wiring boards described above, or may be various known ones. Similarly, the printed circuit boards (1) to (2) may be the printed circuit boards described above, or may be various known ones. The printed wiring board (1) and the printed wiring board (2) may be the same or different. Similarly, printed circuit board (1) and printed circuit board (2) may be the same or different.

[Manufacturing method of multilayer wiring board]
The present disclosure provides steps 1 and 2 below.
Step 1: A step of producing a substrate with an adhesive layer by contacting the adhesive or the film adhesive with at least one side of the printed wiring board (1) or the printed circuit board (1) Step 2: The adhesion Provided is a method for manufacturing a multilayer wiring board, comprising the steps of laminating a printed wiring board (2) or a printed circuit board (2) on a layered base material and pressing the printed wiring board (2) under heat and pressure.

The printed wiring boards (1) and (2) may be the printed wiring boards described above, or may be various known ones. Similarly, the printed circuit boards (1) to (2) may be the printed circuit boards described above, or may be various known ones.

In step 1, the means for bringing the adhesive or film adhesive into contact with the adherend is not particularly limited, and various known coating means, curtain coaters, roll coaters, laminators, presses and the like are exemplified.

The heating temperature and pressure bonding time in step 2 are not particularly limited. After the curing reaction takes about 10 minutes, it is preferable to further heat-treat at about 150° C. to 250° C. for about 10 minutes to 3 hours in order to advance the curing reaction of (a) the cross-linking agent. The pressure is also not particularly limited, but is preferably about 0.5 to 20 MPa, more preferably about 1 to 8 MPa throughout steps (a) and (b).

Hereinafter, the present invention will be described in detail through examples and comparative examples. However, the above description of preferred embodiments and the following examples are provided for illustrative purposes only and not for the purpose of limiting the invention. Accordingly, the scope of the present invention is not limited to the embodiments or examples specifically described herein, but only by the claims. Further, in each example and comparative example, numerical values such as parts and % are based on mass unless otherwise specified.

<Production of polyimide>
Production example 1
4,4′-[Propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride (trade name 65.00 g of "BisDA-1000" manufactured by SABIC Innovative Plastics Japan LLC., hereinafter abbreviated as BisDA) and 144.19 g of cyclohexanone were charged, and the solution was heated to 60.degree. Next, 19.29 g of dimer diamine (trade name “PRIAMINE 1075”, manufactured by Croda Japan Co., Ltd.) and 1,3-bis(aminomethyl)cyclohexane (trade name “1,3-BAC”, manufactured by Mitsubishi Gas Chemical). ) was gradually added, and then 26.22 g of methylcyclohexane and 91.8 g of ethylene glycol dimethyl ether (DMG) were charged, heated to 140°C, and imidization reaction was carried out over 3 hours, A solution of polyimide (1A-1) (nonvolatile content: 26.8%) was obtained. The polyimide resin had an acid component/amine component molar ratio of 1.05 and a softening point of 140°C.

Production examples other than Production Example 1 and Comparative Production Examples were carried out in the same manner as in Production Example 1, except that the composition of the resin solution was changed as shown in Table 1, to obtain polyimides.

ＢｉｓＤＡ：４，４’－［プロパン－２，２－ジイルビス（１，４－フェニレンオキシ）］ジフタル酸二無水物
ＰＲＩＡＭＩＮＥ１０７５：ダイマージアミン、クローダジャパン（株）製。
１，３－ＢＡＣ：１，３－ビス（アミノメチル）シクロヘキサン
ＢＴＤＡ：３，３’，４，４’－ベンゾフェノンテトラカルボン酸二無水物

BisDA: 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride PRIAMINE 1075: dimer diamine, manufactured by Croda Japan.
1,3-BAC: 1,3-bis(aminomethyl)cyclohexane BTDA: 3,3',4,4'-benzophenonetetracarboxylic dianhydride

Example 1
5.69 g of polyimide (1A-1) solution, 4.50 g of polyimide (1B-1) solution, 2.53 g of polyimide (1B-2) solution, N,N-diglycidyl-4-glycidyloxyaniline as a cross-linking agent (manufactured by Mitsubishi Chemical Corporation, trade name "jER630") 0.12 g, cyanate ester resin (trade name "TA", manufactured by Mitsubishi Kagaku Gas Co., Ltd.) methyl ethyl ketone solution (40% non-volatile content) 0.21 g, ( 3) 2.30 g of toluene as an organic solvent, (4) 2.30 g of methyl ethyl ketone dispersion (50% non-volatile content) of spherical silica (trade name “FB-3SDC”, manufactured by Denki Kagaku Kogyo Co., Ltd.) as a flame retardant. And a phosphorus-based flame retardant (trade name “Exolit OP935”, manufactured by Clariant Japan Co., Ltd.) methyl ethyl ketone solution (40% non-volatile content) 1.44 g, and (5) N-2-(aminoethyl )-3-aminopropyltrimethoxysilane (trade name “KBM-603”, manufactured by Shin-Etsu Chemical Co., Ltd.) (0.08 g) was mixed and thoroughly stirred to obtain an adhesive with a non-volatile content of 30.0%. rice field.

Examples and comparative examples other than Example 1 were conducted in the same manner as in Example 1 except that the composition of the adhesive was changed as shown in Table 2 to obtain adhesives.

なお、有機溶剤には、ポリイミドを製造する際に用いた有機溶剤も含み得る。

Note that the organic solvent may also include the organic solvent used when producing the polyimide.

<Preparation of copper-clad laminate>
The adhesive of Example 1 was applied to a rolled copper foil (trade name “GHF5”, manufactured by JX Metals Co., Ltd.) with a gap coater so that the thickness after drying was 12 μm, and then dried at 150 ° C. for 5 minutes. A resin-coated copper foil was obtained. A polyimide film (trade name "Kapton 50EN", manufactured by DuPont-Toray Co., Ltd.) dehumidified at 120° C. for 10 minutes was sandwiched between the two resin-coated copper foils with the adhesive side facing inward. A copper-clad laminate was obtained by heat laminating at 170° C. and 5 MPa for 30 minutes, then using a dryer at 150° C. and 12.5 MPa for 1 minute, and then curing at 180° C. for 4 hours.

<Solder heat resistance test>
After curing, the above copper-clad laminate was floated in a solder bath at 288° C. with the copper foil side down for 30 seconds, and the presence or absence of a change in appearance was confirmed. When there was no change, it was evaluated as ◯, and when there was blistering or blistering, it was evaluated as x. The results are shown in the table.

<Adhesion test>
The peel strength (N/cm) of the resulting copper-clad laminate was measured according to JIS C 6481 (testing method for copper-clad laminate for flexible printed wiring boards). The results are shown in the table.

<Permittivity and dielectric loss tangent measurement>
About 7 g of each of the adhesives of Examples and Comparative Examples was poured into a fluororesin PFA flat plate (diameter 75 mm, manufactured by Sogo Rikagaku Glass Co., Ltd.), and heated at 30° C. for 10 hours, 70° C. for 10 hours, and 100° C. for 6 hours. , 120° C.×6 hours, 150° C.×6 hours, and 180° C.×12 hours to obtain dielectric constant measurement resin and cured product samples having a film thickness of about 300 μm.

Next, according to JIS C2565, the dielectric constant and dielectric loss tangent at 10 GHz of the obtained resin and cured product sample for dielectric constant measurement are measured using a commercially available dielectric constant measurement device (cavity resonator type, manufactured by AET). It was measured. The results are shown in the table.

Claims (10)

A high softening point polyimide having a softening point of 140 to 190° C and a low softening point polyimide having a softening point of 70 to 100 °C , wherein the high softening point polyimide having a softening point of 140°C or higher and the low softening point polyimide having a softening point of 100°C or lower. 5 to 900 parts by mass of a cross-linking agent and 150 to 900 parts by mass of an organic solvent are included for a total of 100 parts by mass (in terms of solid content), and 100 parts by mass of the high softening point polyimide (in terms of solid content), An adhesive containing 70 to 400 parts by mass of a low softening point polyimide . 2. The adhesive according to claim 1, comprising two or more of said low softening point polyimides. A film-like adhesive comprising a heat-cured product of the adhesive according to claim 1 or 2 . An adhesive layer comprising the adhesive according to claim 1 or 2 or the film adhesive according to claim 3 . An adhesive sheet comprising the adhesive layer according to claim 4 and a support film. A resin-coated copper foil comprising the adhesive layer according to claim 4 and a copper foil. A copper-clad laminate comprising the resin-coated copper foil according to claim 6 and the copper foil or insulating sheet. A printed wiring board having a circuit pattern on the copper foil surface of the copper-clad laminate according to claim 7 . printed wiring board (1) or printed circuit board (1),
An adhesive layer according to claim 4 and a printed wiring board (2) or printed circuit board (2),
Multilayer wiring board. A method for manufacturing a multilayer wiring board including the following steps 1 and 2.
Step 1: An adhesive layer is formed by contacting the adhesive according to claim 1 or 2 or the film adhesive according to claim 3 to at least one surface of the printed wiring board (1) or the printed circuit board (1). Step 2: Laminating a printed wiring board (2) or a printed circuit board (2) on the adhesive layer-attached substrate and crimping under heat and pressure.