JP2021070824A - Polyimide composition, resin film, laminate, cover ray film, copper foil with resin, metal-clad laminate and circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyimide composition and a resin film capable of coping with high frequency of electronic equipment by improving dielectric properties while using a diamine diamine composition containing diamine diamine as a main component as a raw material in a certain amount or more. SOLUTION: The main component is (A) a tetracarboxylic acid anhydride component and a diamine diamine obtained by substituting two terminal carboxylic acid groups of dimer acid with a primary aminomethyl group or an amino group with respect to a total diamine component. It contains a polyimide obtained by reacting a diamine component containing 40 mol% or more of the diamine diamine composition, and (B) aromatic condensed phosphoric acid ester, and the weight of the component (B) with respect to the component (A). A polyimide composition having a ratio in the range of 0.05 to 0.7. [Selection diagram] None

Description

The present invention relates to a polyimide composition useful as an adhesive in a circuit board such as a printed wiring board, a resin film, a laminate, a coverlay film, a copper foil with resin, a metal-clad laminate, and a circuit board using the polyimide composition.

In recent years, with the progress of miniaturization, weight reduction, and space saving of electronic devices, a flexible printed wiring board (FPC) that is thin and lightweight, has flexibility, and has excellent durability even after repeated bending. The demand for Circuits) is increasing. Since FPC can be mounted three-dimensionally and at high density even in a limited space, it can be used for wiring of moving parts of electronic devices such as HDDs, DVDs, and mobile phones, and for parts such as cables and connectors. It is expanding.

In addition to the above-mentioned high density, the high performance of the equipment has advanced, so it is also necessary to cope with the high frequency of the transmission signal. In information processing and information communication, efforts are being made to increase the transmission frequency in order to transmit and process large volumes of information, and the printed circuit board material has a transmission loss due to the thinning of the insulating layer and the improvement of the dielectric properties of the insulating layer. Is required to decrease. In the future, FPCs and adhesives that can handle high frequencies will be required, and it will be important to reduce transmission loss.

By the way, as a technique for an adhesive layer containing polyimide as a main component, a polyimide made from a diamine compound derived from an aliphatic diamine such as dimer acid (dimeric fatty acid) and at least two primary amino groups are functionalized. It has been proposed to apply a crosslinked polyimide resin obtained by reacting an amino compound as a group to an adhesive layer of a coverlay film (for example, Patent Document 1). Further, it has been proposed to apply a resin composition in which such a polyimide, a thermosetting resin such as an epoxy resin, and a cross-linking agent are used in combination to a copper-clad laminate (for example, Patent Document 2). However, in Patent Documents 1 and 2, no consideration is given to the influence of by-products other than diamine diamine derived from dimer acid contained in the raw material.

Dimer acid is obtained by a deal-alder reaction using natural fatty acids such as soybean oil fatty acid, tall oil fatty acid, rapeseed oil fatty acid and the like and purified oleic acid, linoleic acid, linolenic acid, erucic acid and the like as raw materials. It is known that a dimerized fatty acid and a polybasic acid compound derived from dimer acid can be obtained as a composition of a raw material fatty acid or a fatty acid having a trimerization or higher (for example, Patent Document 3). ..

Japanese Unexamined Patent Publication No. 2013-1730 JP-A-2017-119361 Japanese Unexamined Patent Publication No. 2017-137375

As a means for controlling the physical properties of a resin containing polyimide as a main component, it is important to control the molecular weight of polyamic acid or polyimide, which is a precursor of polyimide. However, when diaminediamine is applied as a raw material, it is used in a state of containing by-products other than diaminediamine derived from dimer acid. Such by-products make it difficult to control the molecular weight of polyimide, and also affect the dielectric properties over a wide range of frequencies and their humidity dependence.

An object of the present invention is to obtain a polyimide composition and a resin film capable of coping with high frequency of electronic devices by improving dielectric properties while using a diamine diamine composition containing diamine diamine as a main component as a raw material in a certain amount or more. To provide.

The polyimide composition of the present invention has the following components (A) and (B);
(A) Diamine diamine containing a diamine diamine as a main component, in which two terminal carboxylic acid groups of dimer acid are replaced with a primary aminomethyl group or an amino group with respect to the tetracarboxylic acid anhydride component and the total diamine component. Polyimide obtained by reacting with a diamine component containing 40 mol% or more of the composition, and (B) aromatic condensed phosphoric acid ester,
The weight ratio of the component (B) to the component (A) is in the range of 0.05 to 0.7.

In the polyimide composition of the present invention, the weight ratio of the component (B) to the component (A) may be in the range of 0.2 to 0.5.

In the polyimide composition of the present invention, the weight ratio of phosphorus derived from the component (B) to the component (A) may be in the range of 0.01 to 0.1.

In the polyimide composition of the present invention, the weight ratio of phosphorus derived from the component (B) to the diamine diamine composition in the component (A) may be in the range of 0.01 to 0.15.

The polyimide composition of the present invention may further contain an amino compound having at least two primary amino groups as functional groups.

The resin film of the present invention is a resin film containing a polyimide layer, and the polyimide layer contains the following components (A) and (B);
(A) Diamine diamine containing a diamine diamine as a main component, in which two terminal carboxylic acid groups of dimer acid are replaced with a primary aminomethyl group or an amino group with respect to the tetracarboxylic acid anhydride component and the total diamine component. Polyimide obtained by reacting with a diamine component containing 40 mol% or more of the composition, and (B) aromatic condensed phosphoric acid ester,
The weight ratio of the component (B) to the component (A) is in the range of 0.05 to 0.7.

The laminate of the present invention is a laminate having a base material and an adhesive layer laminated on at least one surface of the base material.
The adhesive layer is made of the resin film.

The coverlay film of the present invention is a coverlay film having a coverlay film material layer and an adhesive layer laminated on the coverlay film material layer.
The adhesive layer is made of the resin film.

The copper foil with resin of the present invention is a copper foil with resin in which an adhesive layer and a copper foil are laminated.
The adhesive layer is made of the resin film.

The metal-clad laminate of the present invention is a metal-clad laminate having an insulating resin layer and a metal layer laminated on at least one surface of the insulating resin layer.
At least one of the insulating resin layers is made of the resin film.

The circuit board of the present invention is a circuit board formed by wiring the metal layer of the metal-clad laminate.

Since the polyimide composition of the present invention contains a polyimide derived from a diamine containing diamine as a main component and an aromatic condensed phosphoric acid ester, a resin film having excellent dielectric properties can be formed. Further, the resin film of the present invention has low humidity dependence of dielectric properties and is excellent in stability. Therefore, the polyimide composition and the resin film of the present invention can be particularly preferably used for a circuit board such as an FPC in an electronic device that requires high-speed signal transmission, for example.

Hereinafter, embodiments of the present invention will be described.
The polyimide composition of the present embodiment has the following components (A) and (B);
(A) Diamine diamine containing a diamine diamine as a main component, in which two terminal carboxylic acid groups of dimer acid are replaced with a primary aminomethyl group or an amino group with respect to the tetracarboxylic acid anhydride component and the total diamine component. Polyimide obtained by reacting with a diamine component containing 40 mol% or more of the composition, and (B) aromatic condensed phosphoric acid ester,
The weight ratio of the component (B) to the component (A) is in the range of 0.05 to 0.7.

[(A) component; polyimide]
The polyimide of the component (A) is mainly composed of a tetracarboxylic acid anhydride component and a diamine diamine in which two terminal carboxylic acid groups of dimer acid are replaced with a primary aminomethyl group or an amino group with respect to the total diamine component. It is an imidized precursor polyamic acid obtained by reacting with a diamine component containing 40 mol% or more of the diamine diamine composition.

(Tetracarboxylic dianhydride component)
The polyimide of the present embodiment can contain, without particular limitation, a tetracarboxylic acid residue derived from a tetracarboxylic dian anhydride generally used for thermoplastic polyimides, but with respect to all tetracarboxylic acid residues. It is preferable that a total of 90 mol% or more of tetracarboxylic acid residues derived from the tetracarboxylic acid anhydride represented by the following general formula (1) is contained. By containing a total of 90 mol% or more of tetracarboxylic acid residues derived from the tetracarboxylic dianhydride represented by the following general formula (1) with respect to all tetracarboxylic acid residues, the polyimide It is preferable that both flexibility and heat resistance are easy to achieve. If the total amount of tetracarboxylic acid residues derived from the tetracarboxylic dianhydride represented by the following general formula (1) is less than 90 mol%, the solvent solubility of the polyimide tends to decrease.

In the general formula (1), X represents a single bond or a divalent group selected from the following formula.

In the above formula, Z is _{-C 6 H 4 -, - (} CH 2) n- or _{-CH 2 -CH (-O-C (} = O) -CH 3) -CH 2 - are illustrated, n represents 1 Indicates an integer of ~ 20.

The "thermoplastic polyimide" is generally a polyimide in which the glass transition temperature (Tg) can be clearly confirmed, but in the present invention, it is measured at 30 ° C. using a dynamic viscoelasticity measuring device (DMA). A polyimide having a storage elastic modulus of 1.0 × 10 ⁸ Pa or more and a storage elastic modulus of ^{less than 3.0 × 10 7 Pa at 300 ° C.} The "non-thermoplastic polyimide" is a polyimide that generally does not soften or show adhesiveness even when heated, but in the present invention, it was measured using a dynamic viscoelasticity measuring device (DMA). A polyimide having a storage elastic modulus of 1.0 × 10 ⁹ Pa or more at ° C. and a storage elastic modulus of 3.0 × 10 ⁸ Pa or more at 300 ° C.

Examples of the tetracarboxylic dianhydride represented by the general formula (1) include 3,3', 4,4'-biphenyltetracarboxylic dianhydride (BPDA), 3,3', 4,4'. -Benzophenone tetracarboxylic dianhydride (BTDA), 3,3', 4,4'-diphenylsulfonetetracarboxylic dianhydride (DSDA), 4,4'-oxydiphthalic anhydride (ODPA), 4,4 '-(Hexafluoroisopropylidene) diphthalic anhydride (6FDA), 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride (BPADA), p-phenylenebis (trimerit) Acid monoesteric anhydride) (TAHQ), ethylene glycol bisamhydrotrimeritate (TMEG) and the like can be mentioned. Among these, especially when 3,3', 4,4'-benzophenone tetracarboxylic acid dianhydride (BTDA) is used, the adhesiveness of the polyimide can be improved, and the ketone group present in the molecular skeleton can be used. The amino group of the amino compound for forming a crosslink, which will be described later, may react to form a C = N bond, and the effect of improving heat resistance is likely to be exhibited. From this point of view, it is preferable to contain BTDA-derived tetracarboxylic acid residue in an amount of preferably 50 mol% or more, more preferably 60 mol% or more, based on the total tetracarboxylic acid residue.

The polyimide of the component (A) contains a tetracarboxylic acid residue derived from an acid anhydride other than the tetracarboxylic acid anhydride represented by the above general formula (1) as long as the effect of the invention is not impaired. Can be done. Such tetracarboxylic acid residues are not particularly limited, but for example, pyromellitic acid dianhydride, 2,3', 3,4'-biphenyltetracarboxylic acid dianhydride, 2,2', 3 , 3'-or 2,3,3', 4'-benzophenone tetracarboxylic acid dianhydride, 2,3', 3,4'-diphenyl ether tetracarboxylic acid dianhydride, bis (2,3-dicarboxyphenyl) ) Ether dianhydride, 3,3'', 4,4''-, 2,3,3'', 4''-or 2,2'',3,3''-p-terphenyltetracarboxylic Acid dianhydride, 2,2-bis (2,3- or 3,4-dicarboxyphenyl) -propane dianhydride, bis (2,3- or 3,4-dicarboxyphenyl) methane dianhydride, Bis (2,3- or 3,4-dicarboxyphenyl) sulfonate dianhydride, 1,1-bis (2,3- or 3,4-dicarboxyphenyl) ethane dianhydride, 1,2,7, 8-1,2,6,7- or 1,2,9,10-phenanthrene-tetracarboxylic dianhydride, 2,3,6,7-anthracene tetracarboxylic dianhydride, 2,2-bis (3,4-Dicarboxyphenyl) Tetrafluoropropane dianhydride, 2,3,5,6-cyclohexane dianhydride 1,2,5,6-naphthalene tetracarboxylic acid dianhydride 1,4,5 , 8-Naphthalenetetracarboxylic dianhydride, 2,3,6,7-Naphthalenetetracarboxylic hydride, 4,8-Dimethyl-1,2,3,5,6,7-Hexahydronaphthalene-1 , 2,5,6-Tetracarboxylic acid dianhydride, 2,6- or 2,7-dichloronaphthalene-1,4,5,8-Tetracarboxylic acid dianhydride, 2,3,6,7-( Or 1,4,5,8-) tetrachloronaphthalene-1,4,5,8-(or 2,3,6,7-) tetracarboxylic dianhydride, 2,3,8,9-3 , 4,9,10-, 4,5,10,11-or 5,6,11,12-perylene-tetracarboxylic hydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride Pyrazine-2,3,5,6-tetracarboxylic acid dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic acid dianhydride, thiophene-2,3,4,5-tetracarboxylic acid dianhydride Examples thereof include tetracarboxylic acid residues derived from aromatic tetracarboxylic acid dianhydrides such as anhydrides, 4,4'-bis (2,3-dicarboxyphenoxy) diphenylmethane dianhydrides.

(Diamine component)
As the polyimide of the component (A), a diamine component containing 40 mol% or more, more preferably 60 mol% or more of the diamine diamine composition is used as a raw material with respect to the total diamine component. That is, the polyimide of the component (A) contains 40 mol% or more, preferably 60 mol% or more of the diamine residue derived from the diamine diamine composition with respect to the total diamine residue. By using the dimer diamine composition in the above amount, the dielectric property of the polyimide is improved, the thermocompression bonding property is improved by lowering the glass transition temperature of the polyimide (lower Tg), and the internal stress is lowered by lowering the elastic modulus. Can be alleviated.

(Diamine Diamine Composition)
The diamine diamine composition contains the following component (a) as a main component, and the amounts of the components (b) and (c) are controlled.

(A) Dimer diamine;
In the diamine diamine of the component (a), the two terminal carboxylic acid groups (-COOH) of the dimer acid are replaced with _{a primary aminomethyl group (-CH 2-} NH ₂ ) or an amino group (-NH _2). It means diamine. Dimeric acid is a known dibasic acid obtained by the intermolecular polymerization reaction of unsaturated fatty acids, and its industrial production process is almost standardized in the industry, and unsaturated fatty acids having 11 to 22 carbon atoms are used as clay catalysts. It is obtained by dimerizing with. The industrially obtained dimer acid is mainly composed of a dibasic acid having 36 carbon atoms obtained by dimerizing an unsaturated fatty acid having 18 carbon atoms such as oleic acid, linolenic acid and linolenic acid. Depending on the degree, it contains an arbitrary amount of monomeric acid (18 carbon atoms), trimeric acid (54 carbon atoms), and other polymerized fatty acids having 20 to 54 carbon atoms. Further, although the double bond remains after the dimerization reaction, in the present invention, the dimer acid is also included in which the degree of unsaturation is lowered by the hydrogenation reaction. The dimer diamine of the component (a) is prepared by substituting a primary aminomethyl group or an amino group for the terminal carboxylic acid group of the dibasic acid compound in the range of 18 to 54 carbon atoms, preferably 22 to 44 carbon atoms. It can be defined as the resulting diamine compound.

As a characteristic of dimer diamine, it is possible to impart properties derived from the skeleton of dimer acid. That is, since dimer diamine is an aliphatic of macromolecules having a molecular weight of about 560 to 620, the molar volume of the molecule can be increased and the polar groups of polyimide can be relatively reduced. It is considered that such a feature of the dimer acid type diamine contributes to improving the dielectric property by reducing the dielectric constant and the dielectric loss tangent while suppressing the decrease in the heat resistance of the polyimide. Further, since it has two free-moving hydrophobic chains having 7 to 9 carbon atoms and two chain-like aliphatic amino groups having a length close to 18 carbon atoms, it not only gives flexibility to the polyimide, but also gives the polyimide flexibility. Since the polyimide can have an asymmetrical chemical structure or a non-planar chemical structure, it is considered that the polyimide can have a low dielectric constant.

The diamine diamine composition used is such that the diamine diamine content of the component (a) is increased to 96% by weight or more, preferably 97% by weight or more, more preferably 98% by weight or more by a purification method such as molecular distillation. That's good. By setting the diamine diamine content of the component (a) to 96% by weight or more, it is possible to suppress the spread of the molecular weight distribution of polyimide. If technically possible, it is best that all (100% by weight) of the diamine diamine composition is composed of the diamine diamine component (a).

(B) A monoamine compound obtained by substituting a terminal carboxylic acid group of a monobasic acid compound having 10 to 40 carbon atoms with a primary aminomethyl group or an amino group;
The monobasic acid compound in the range of 10 to 40 carbon atoms is a monobasic unsaturated fatty acid in the range of 10 to 20 carbon atoms derived from the raw material of dimer acid, and a by-product during the production of dimer acid. It is a mixture of monobasic acid compounds in the range of 21 to 40 carbon atoms. The monoamine compound is obtained by substituting the terminal carboxylic acid group of these monobasic acid compounds with a primary aminomethyl group or an amino group.

The monoamine compound of the component (b) is a component that suppresses an increase in the molecular weight of polyimide. During the polymerization of polyamic acid or polyimide, the monofunctional amino group of the monoamine compound reacts with the terminal acid anhydride group of the polyamic acid or polyimide to seal the terminal acid anhydride group, and the molecular weight of the polyamic acid or polyimide is sealed. Suppress the increase.

(C) An amine compound obtained by substituting a primary aminomethyl group or an amino group for a terminal carboxylic acid group of a polybasic acid compound having a hydrocarbon group in the range of 41 to 80 carbon atoms (however, the dimerdiamine). except for);
The polybasic acid compound having a hydrocarbon group in the range of 41 to 80 carbon atoms is mainly composed of a tribasic acid compound in the range of 41 to 80 carbon atoms, which is a by-product during the production of dimer acid. It is a polybasic acid compound. Further, it may contain a polymerized fatty acid other than dimer acid having 41 to 80 carbon atoms. The amine compound is obtained by substituting the terminal carboxylic acid group of these polybasic acid compounds with a primary aminomethyl group or an amino group.

The amine compound of the component (c) is a component that promotes an increase in the molecular weight of polyimide. A trifunctional or higher amino group containing a triamine derived from trimeric acid as a main component reacts with a polyamic acid or a terminal acid anhydride group of polyimide to rapidly increase the molecular weight of polyimide. Further, an amine compound derived from a polymerized fatty acid other than dimer acid having 41 to 80 carbon atoms also increases the molecular weight of the polyimide and causes gelation of the polyamic acid or the polyimide.

The above diamine diamine composition is used to facilitate confirmation of peak start, peak top and peak end of each component of the diamine diamine composition when quantification of each component is performed by measurement using gel permeation chromatography (GPC). In addition, a sample obtained by treating the diamine diamine composition with anhydrous acetic acid and pyridine is used, and cyclohexanone is used as an internal standard substance. Using the sample prepared in this way, each component is quantified by the area percentage of the GPC chromatogram. The peak start and peak end of each component are set to the minimum value of each peak curve, and the area percentage of the chromatogram can be calculated based on this.

Further, in the diamine diamine composition used in the present invention, the total of the components (b) and (c) is 4% or less, preferably less than 4%, in terms of the area percentage of the chromatogram obtained by GPC measurement. By setting the total of the components (b) and (c) to 4% or less, it is possible to suppress the spread of the molecular weight distribution of the polyimide.

The area percentage of the chromatogram of the component (b) is preferably 3% or less, more preferably 2% or less, still more preferably 1% or less. By setting the range in such a range, it is possible to suppress a decrease in the molecular weight of the polyimide, and further expand the range of the molar ratio of the tetracarboxylic acid anhydride component and the diamine component. The component (b) may not be contained in the diamine diamine composition.

The area percentage of the chromatogram of the component (c) is 2% or less, preferably 1.8% or less, and more preferably 1.5% or less. Within such a range, a rapid increase in the molecular weight of the polyimide can be suppressed, and an increase in the dielectric loss tangent of the resin film at a wide frequency range can be suppressed. The component (c) may not be contained in the diamine diamine composition.

When the area percent ratio (b / c) of the chromatograms of the components (b) and (c) is 1 or more, the molar ratio of the tetracarboxylic acid anhydride component and the diamine component (tetracarboxylic acid anhydride component / The diamine component) is preferably 0.97 or more and less than 1.0, and such a molar ratio makes it easier to control the molecular weight of the polyimide.

Further, when the ratio (b / c) of the area percentage of the chromatograms of the components (b) and (c) is less than 1, the molar ratio of the tetracarboxylic acid anhydride component and the diamine component (tetracarboxylic acid anhydride component). The / diamine component) is preferably 0.97 or more and 1.1 or less, and such a molar ratio makes it easier to control the molecular weight of the polyimide.

The weight average molecular weight of the polyimide is preferably in the range of, for example, 10,000 to 200,000, and within such a range, the weight average molecular weight of the polyimide can be easily controlled. Further, for example, when applied as an adhesive for FPC, the weight average molecular weight of polyimide is more preferably in the range of 20,000 to 150,000, and further preferably in the range of 40,000 to 150,000. When the weight average molecular weight of the polyimide is less than 20,000, the flow resistance tends to deteriorate. On the other hand, when the weight average molecular weight of polyimide exceeds 150,000, the viscosity becomes excessively increased and becomes insoluble in a solvent, and defects such as uneven thickness of the adhesive layer and streaks tend to occur during coating work. Become.

The diamine diamine composition used in the present invention is preferably purified for the purpose of reducing the component (a) other than the diamine diamine. The purification method is not particularly limited, but a known method such as a distillation method or precipitation purification is preferable. The diamine diamine composition before purification can be obtained as a commercially available product, and examples thereof include PRIAMINE 1073 (trade name), PRIAMINE 1074 (trade name), and PRIAMINE 1075 (trade name) manufactured by Croda Japan.

Examples of the diamine compound other than the diamine diamine used for the polyimide include an aromatic diamine compound and an aliphatic diamine compound. Specific examples thereof include 1,4-diaminobenzene (p-PDA; paraphenylenediamine), 2,2'-dimethyl-4,4'-diaminobiphenyl (m-TB), 2,2'-n-. Propyl-4,4'-diaminobiphenyl (m-NPB), 4-aminophenyl-4'-aminobenzoate (APAB), 2,2-bis- [4- (3-aminophenoxy) phenyl] propane, bis [ 4- (3-Aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) biphenyl, bis [1- (3-aminophenoxy)] biphenyl, bis [4- (3-aminophenoxy) phenyl] methane , Bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy)] benzophenone, 9,9-bis [4- (3-aminophenoxy) phenyl] fluorene, 2,2- Bis- [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis- [4- (3-aminophenoxy) phenyl] hexafluoropropane, 3,3'-dimethyl-4,4'- Diaminobiphenyl, 4,4'-methylenedi-o-toluidine, 4,4'-methylenedi-2,6-xylidine, 4,4'-methylene-2,6-diethylaniline, 3,3'-diaminodiphenylethane, 3,3'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 3,3''-diamino-p-terphenyl, 4,4'-[1,4-phenylenebis (1-methylethylidene)] bisaniline, 4,4'-[1,3-phenylenebis (1-methylethylidene)] bisaniline, bis (p-aminocyclohexyl) methane, bis (p-β-amino-t-butylphenyl) ether, bis (p-β) -Methyl-δ-aminopentyl) benzene, p-bis (2-methyl-4-aminopentyl) benzene, p-bis (1,1-dimethyl-5-aminopentyl) benzene, 1,5-diaminonaphthalene, 2 , 6-diaminonaphthalene, 2,4-bis (β-amino-t-butyl) toluene, 2,4-diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m -Xylylene diamine, p-xylylene diamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2,5-diamino-1,3,4-oxadiazole, piperazine, 2'-methoxy-4, 4'-Diaminobenzanilide, 4,4'-Zia Minobensanilide, 1,3-bis [2- (4-aminophenyl) -2-propyl] benzene, 6-amino-2- (4-aminophenoxy) benzoxazole, 1,3-bis (3-aminophenoxy) ) Examples thereof include diamine compounds such as benzene.

Polyimide can be produced by reacting the above-mentioned tetracarboxylic acid anhydride component and diamine component in a solvent to generate polyamic acid, and then heat-closing the ring. For example, the tetracarboxylic dianhydride component and the diamine component are dissolved in an organic solvent in approximately equimolar amounts, and the mixture is stirred at a temperature in the range of 0 to 100 ° C. for 30 minutes to 24 hours for a polymerization reaction to cause a polyimide precursor. Polyamic acid is obtained. In the reaction, the reaction components are dissolved in the organic solvent so that the precursor produced is in the range of 5 to 50% by weight, preferably in the range of 10 to 40% by weight. Examples of the organic solvent used in the polymerization reaction include N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N, N-diethylacetamide, N-methyl-2-pyrrolidone (NMP), 2 -Butanone, dimethyl sulfoxide (DMSO), hexamethylphosphoramide, N-methylcaprolactam, dimethylsulfate, cyclohexanone, methylcyclohexane, dioxane, tetrahydrofuran, diglime, triglime, methanol, ethanol, benzyl alcohol, cresol and the like can be mentioned. Two or more of these solvents can be used in combination, and aromatic hydrocarbons such as xylene and toluene can be used in combination. The amount of such an organic solvent used is not particularly limited, but it should be adjusted so that the concentration of the polyamic acid solution obtained by the polymerization reaction is about 5 to 50% by weight. Is preferable.

The synthesized polyamic acid is usually advantageous to be used as a reaction solvent solution, but can be concentrated, diluted or replaced with another organic solvent if necessary. In addition, polyamic acid is generally excellent in solvent solubility, and is therefore advantageously used. The viscosity of the polyamic acid solution is preferably in the range of 500 cps to 100,000 cps. If it is out of this range, defects such as thickness unevenness and streaks are likely to occur in the film during coating work by a coater or the like.

The method of imidizing the polyamic acid to form the polyimide is not particularly limited, and for example, a heat treatment such as heating in the solvent at a temperature in the range of 80 to 400 ° C. for 1 to 24 hours is preferably adopted. Will be done. Further, the temperature may be heated under a constant temperature condition, or the temperature may be changed in the middle of the process.

In the polyimide of the present embodiment, by selecting the types of the tetracarboxylic acid anhydride component and the diamine component and the molar ratio of each when two or more types of the tetracarboxylic acid anhydride component or the diamine component are applied, It is possible to control the dielectric property, the coefficient of thermal expansion, the tensile elastic modulus, the glass transition temperature, and the like. Further, in the polyimide of the present embodiment, when a plurality of structural units of polyimide are present, they may exist as blocks or randomly, but preferably randomly.

The imide group concentration of the polyimide of the present embodiment is preferably 22% by weight or less, more preferably 20% by weight or less. Here, the "imide group concentration" means a value obtained by dividing the molecular weight of the imide base portion (-(CO) ₂ -N-) in the polyimide by the molecular weight of the entire structure of the polyimide. When the imide group concentration exceeds 22% by weight, the molecular weight of the resin itself becomes small, the low hygroscopicity deteriorates due to the increase in polar groups, and the Tg and elastic modulus increase.

The polyimide of the present embodiment most preferably has a completely imidized structure. However, a part of the polyimide may be amic acid. ^{The imidization rate is around 1015 cm -1} by measuring the infrared absorption spectrum of the polyimide thin film by the single reflection ATR method using a Fourier transform infrared spectrophotometer (commercially available: FT / IR620 manufactured by Nippon Spectroscopy). It can be calculated from the absorbance of C = O expansion and contraction derived from the imide group of ^{1780 cm -1} based on the benzene ring absorber of.

[Component (B); Aromatic Condensed Phosphate Ester]
The polyimide composition of the present embodiment contains the aromatic condensed phosphoric acid ester of the component (B). Here, the "aromatic condensed phosphoric acid ester" is a phosphoric acid ester compound having a chemical structure in which two or more phosphoric acid ester units are linked by a divalent organic group having an aromatic ring, or phosphorus oxychloride. Means the reaction product of a divalent phenolic compound and a phenol or an alkylphenol. By combining the aromatic condensed phosphoric acid ester with the polyimide obtained by using a certain amount or more of the dimer diamine composition, the dielectric property can be improved. The reason for this is not yet clear, but due to the unique chemical structure of the aromatic condensed phosphate, the dielectric properties of the aromatic condensed phosphate itself and the compatibility with the polyimide obtained using the diamine diamine composition are However, since it does not excessively increase the motility of the molecular chain, it is presumed to contribute to lowering the dielectric constant and lowering the dielectric constant tangent.

As a preferable example of the aromatic condensed phosphoric acid ester, a compound having the structure of the following general formula (2) can be mentioned.

In the general formula (2), a plurality of Rs are aromatic hydrocarbon groups which may independently have a substituent, Ar is a divalent organic group having an aromatic ring, and n is 1. It means the above integers. The aromatic condensed phosphoric acid ester represented by the general formula (2) may be a dimer in which n is 1, or a multimer in which n is 2 or more. Further, the compound is not limited to a single compound, and may be a mixture.

As the aromatic hydrocarbon group which may have a substituent, which is represented by R in the general formula (2), for example, an aryl group having 6 to 15 carbon atoms can be mentioned, and more specifically. Examples include a phenyl group, a methylphenyl group, a dimethylphenyl group, a trimethylphenyl group, an ethylphenyl group, a butylphenyl group, a nonylphenyl group and the like.
Further, in the general formula (2), as a preferable example of the divalent organic group represented by Ar, for example, an alkylene group, an arylene group and the like can be mentioned, and these have a substituent. May be good. More preferable ones include, for example, a phenylene group and a group represented by the following formula (3).

In formula (3), Y is a single bond, -CH _2- , -C (CH ₃ ) _2- , -SO _2- , -C ₅ H _10- , -C ₆ H _12- , -C ₇ H _14- , -C ₈ H _16-, etc.
Among the groups represented by the formula (3), a biphenyldiyl group in which Y is a single bond is more preferable.

Examples of the aromatic condensed phosphoric acid ester include resorcinol bis-diphenyl phosphate, resorcinol bis-dixylenyl phosphate, and bisphenol A bis-diphenyl phosphate. Commercially available products are available as these aromatic condensed phosphoric acid esters, for example, CR-733S (trade name), CR-741 (trade name), CR-747 (trade name), PX-200 (commodity name). Name), PX-200B (trade name) [above, manufactured by Daihachi Chemical Industry Co., Ltd.] and the like. Two or more kinds of these aromatic condensed phosphoric acid esters may be used in combination.

[Mixing amount]
The weight ratio of the component (B) to the component (A) in the polyimide composition of the present embodiment is in the range of 0.05 to 0.7, and the film such as the tensile elastic modulus when the resin film is formed. Considering the physical properties, it is preferably in the range of 0.2 to 0.5. If the weight ratio of the component (B) to the component (A) is less than 0.05, the improvement of the dielectric property may be insufficient, and if it exceeds 0.7, it may be difficult to form the polyimide. In addition, the obtained polyimide film may be weakened. The dielectric property can be improved by setting the blending amount of the component (B) within the above range.

Further, in the polyimide composition of the present embodiment, the weight ratio of phosphorus derived from the component (B) to the polyimide of the component (A) is in the range of 0.01 to 0.1 for the component (B). It is preferable to blend. If the weight ratio of phosphorus derived from the component (B) is less than 0.01, the improvement of the dielectric property is insufficient, and if it exceeds 0.1, the polyimide film (or the polyimide layer) may be weakened.

The component (B) in the polyimide composition of the present embodiment is the weight ratio of phosphorus derived from the component (B) to the diamine diamine composition contained in the component (A) {phosphorus derived from the component (B) / (A). The diamine diamine composition} in the component is preferably in the range of 0.01 to 0.15. If it is less than the above lower limit, the improvement of the dielectric property may be insufficient, and if it exceeds the above upper limit, it may be difficult to form the polyimide, and the obtained polyimide film may be weakened.

<Crosslink formation>
When the polyimide of the component (A) has a ketone group, it may be referred to as an amino compound having the ketone group and at least two primary amino groups as functional groups (hereinafter, referred to as "crosslink-forming amino compound"). ) Is reacted to form a C = N bond, whereby a crosslinked structure can be formed. By forming the crosslinked structure, the heat resistance of the thermoplastic polyimide forming the adhesive layer can be improved. Preferred tetracarboxylic acid anhydrides for forming thermoplastic polyimides having a ketone group include, for example, 3,3', 4,4'-benzophenone tetracarboxylic acid dianhydride (BTDA), and diamine compounds include, for example. Aromatic diamines such as 4,4'-bis (3-aminophenoxy) benzophenone (BABP) and 1,3-bis [4- (3-aminophenoxy) benzoyl] benzene (BABB) can be mentioned.

For the purpose of forming a crosslinked structure, the polyimide composition of the present embodiment particularly contains BTDA residues derived from BTDA in an amount of preferably 50 mol% or more, more preferably 50 mol% or more, based on all tetracarboxylic acid residues. It is preferable to contain the polyimide of the component (A) containing 60 mol% or more and the amino compound for forming a crosslink. In the present invention, the "BTDA residue" means a tetravalent group derived from BTDA.

Examples of the crosslink-forming amino compound include (I) a dihydrazide compound, (II) an aromatic diamine, and (III) an aliphatic amine. Among these, dihydrazide compounds are preferable. Aliphatic amines other than dihydrazide compounds tend to form crosslinked structures even at room temperature, and there is a concern about storage stability of varnishes, while aromatic diamines need to be heated to a high temperature in order to form crosslinked structures. As described above, when the dihydrazide compound is used, both the storage stability of the varnish and the shortening of the curing time can be achieved at the same time. Examples of the dihydrazide compound include dihydrazide oxalic acid, dihydrazide malonate, dihydrazide succinic acid, dihydrazide glutalide, adipic acid dihydrazide, dihydrazide dihydric acid, dihydrazide sberinate, dihydrazide azeline acid, dihydrazide sebacic acid, and dihydrazide sevacinate. Dihydrazide, dihydrazide fumarate, diglycolic acid dihydrazide, tartrate dihydrazide, malic acid dihydrazide, phthalic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, 2,6-naphthoediic acid dihydrazide, 4,4-bisbenzenedihydrazide, 1,4 Dihydrazide compounds such as −naphthoic acid dihydrazide, 2,6-pyridinediacid dihydrazide, and itaconic acid dihydrazide are preferred. The above dihydrazide compounds may be used alone or in combination of two or more.

Further, the amino compounds such as (I) dihydrazide compound, (II) aromatic diamine, and (III) aliphatic amine are, for example, a combination of (I) and (II), a combination of (I) and (III), and the like. It is also possible to use two or more combinations across categories, such as the combination of (I), (II) and (III).

Further, from the viewpoint of making the network structure formed by cross-linking with the cross-linking amino compound more dense, the cross-linking amino compound used in the present invention has a molecular weight (when the cross-linking amino compound is an oligomer). The weight average molecular weight) is preferably 5,000 or less, more preferably 90 to 2,000, and even more preferably 100 to 1,500. Among these, an amino compound for cross-linking having a molecular weight of 100 to 1,000 is particularly preferable. When the molecular weight of the cross-linking amino compound is less than 90, only one amino group of the cross-linking amino compound forms a C = N bond with the ketone group of the polyimide resin, and the periphery of the remaining amino groups is sterically formed. Due to the bulkiness, the remaining amino groups tend to be difficult to form a C = N bond.

In the case of cross-linking the ketone group in the polyimide of the component (A) and the amino compound for cross-linking, the amino compound for cross-linking is added to the resin solution containing the component (A) to form a cross-linking amino compound in the polyimide. A condensation reaction is carried out with the primary amino group of the cross-linking amino compound. By this condensation reaction, the resin solution is cured to become a cured product. In this case, the amount of the amino compound for forming a bridge is 0.004 mol to 1.5 mol, preferably 0.005 mol to 1.2 mol, in total of the primary amino group with respect to 1 mol of the ketone group. It can be more preferably 0.03 mol to 0.9 mol, and most preferably 0.04 mol to 0.6 mol. If the amount of the cross-linking amino compound added so that the total number of primary amino groups is less than 0.004 mol with respect to 1 mol of the ketone group, the cross-linking by the cross-linking amino compound is not sufficient, and therefore after curing. Heat resistance tends to be difficult to develop, and when the amount of the cross-linking amino compound added exceeds 1.5 mol, the unreacted cross-linking amino compound acts as a thermoplastic agent, and the heat resistance as the adhesive layer is lowered. Tends to let.

The conditions for the condensation reaction for cross-linking are the conditions under which the ketone group in the polyimide of component (A) reacts with the primary amino group of the cross-linking amino compound to form an imine bond (C = N bond). If there is, there is no particular limitation. The temperature of the heat condensation is for releasing the water generated by the condensation to the outside of the system, or for simplifying the condensation step when the heat condensation reaction is subsequently carried out after the synthesis of the polyimide of the component (A). For example, the range of 120 to 220 ° C. is preferable, and the range of 140 to 200 ° C. is more preferable. The reaction time is preferably about 30 minutes to 24 hours. The end point of the reaction is the absorption derived from the ketone group in the polyimide resin near ^{1670 cm -1} by measuring the infrared absorption spectrum using, for example, a Fourier transform infrared spectrophotometer (commercially available product: FT / IR620 manufactured by JASCO Corporation). It can be confirmed by the decrease or disappearance of the peak and the appearance of the absorption peak derived from the imine group near ^{1635 cm-1.}

The thermal condensation of the ketone group of the polyimide component (A) and the primary amino group of the above-mentioned cross-linking amino compound is, for example,
(1) A method in which an amino compound for forming a crosslink is added and heated following the synthesis (imidization) of the polyimide of the component (A).
(2) An excess amount of an amino compound is charged in advance as a diamine component, and following the synthesis (imidization) of the polyimide of the component (A), the remaining amino compounds that are not involved in imidization or amidization are cross-linked amino compounds. A method of heating with polyimide, or
(3) The polyimide composition of the component (A) to which the above cross-linking amino compound is added is processed into a predetermined shape (for example, after being applied to an arbitrary base material or formed into a film) and then heated. It can be done by the method of doing.

In order to impart heat resistance to the polyimide of the component (A), the formation of an imine bond was described in the formation of a crosslinked structure, but the present invention is not limited to this, and as a method for curing the polyimide of the component (A), for example, an epoxy resin. , An epoxy resin curing agent, a compound having an unsaturated bond such as maleimide, an activated ester resin, or a resin having a styrene skeleton can be blended and cured.

[Arbitrary component]
The polyimide composition of the present embodiment preferably further contains an inorganic filler in addition to the crosslink-forming amino compound as an optional component. Further, if necessary, other resin components such as plasticizers, epoxy resins, fluororesins, and olefin resins, curing accelerators, coupling agents, organic fillers, pigments, flame retardants, etc. are appropriately added as other optional components. be able to. However, some plasticizers contain a large amount of polar groups, which may promote the diffusion of copper from the copper wiring. Therefore, it is preferable not to use the plasticizer as much as possible.
Further, the polyimide composition of the present embodiment can contain a solvent such as an organic solvent. Examples of the organic solvent include N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N, N-diethylacetamide, N-methyl-2-pyrrolidone (NMP), 2-butanone, and dimethyl. Examples thereof include sulfoxide (DMSO), hexamethylphosphoramide, N-methylcaprolactam, dimethylformamide, cyclohexanone, dioxane, tetrahydrofuran, diglime, triglime, cresol and the like. Two or more of these solvents can be used in combination, and aromatic hydrocarbons such as xylene and toluene can be used in combination. The content of the organic solvent is not particularly limited, but it is preferable to adjust the content so that the concentration of polyamic acid or polyimide is about 5 to 30% by weight.

[Preparation of polyimide composition]
In preparing the polyimide composition, for example, the component (B) may be directly blended with a polyamic acid or a polyimide resin solution prepared using an arbitrary solvent. Alternatively, in consideration of the solubility, mixing and dispersibility of the component (B), the component (B) is previously added to the reaction solvent in which either the acid dianhydride component or the diamine component, which is the raw material of the polyamic acid, is added. After that, the other raw material may be added under stirring to proceed with the polymerization. In either method, the component (B) may be added in the entire amount at one time, or may be added little by little in several times. In addition, the raw materials may be added all at once, or may be divided into several times and mixed little by little.

The polyimide composition of the present embodiment has excellent flexibility and thermoplasticity when an adhesive layer is formed by using the polyimide composition, and is a cover that protects a wiring portion such as an FPC or a rigid flex circuit board. It has preferable properties as an adhesive for ray films.

[Resin film]
The resin film of the present embodiment is a resin film containing a polyimide layer, and the polyimide layer is formed by forming a film containing the solid content (remaining portion excluding the solvent) of the polyimide composition as a main component. That is, the resin film of the present embodiment contains the component (A) and the component (B), and the weight ratio of the component (B) to the component (A) is in the range of 0.05 to 0.7. .. The resin film of the present embodiment has two terminal carboxylic acids, a tetracarboxylic acid anhydride component and a total diamine component, as resin components, in order to impart excellent high frequency characteristics and stability to humidity. It contains a polyimide obtained by reacting a diamine component containing 40 mol% or more of a diamine diamine composition containing a diamine diamine as a main component, the group of which is substituted with a primary aminomethyl group or an amino group. The resin film of the present embodiment may contain, for example, a filler as an optional component other than the resin component.

The resin film of the present embodiment is not particularly limited as long as it is an insulating resin film containing a polyimide layer formed from the above-mentioned polyimide composition, and may be a film (sheet) made of an insulating resin. , A copper foil, a glass plate, a polyimide film, a polyamide film, a resin sheet such as a polyester film, or the like, which may be an insulating resin film laminated on a base material.

(Dielectric property)
The resin film of the present embodiment has the following formula (i),
E ₁ = √ε ₁ × Tan δ ₁ ... (i)
[Here, ε ₁ indicates the permittivity at 10 GHz measured by a split post dielectric resonator (SPDR) after humidity control for 24 hours under a constant temperature and humidity condition (normal state) of 23 ° C. and 50% RH. , Tanδ ₁ shows a dielectric loss tangent at 10 GHz measured by SPDR after 24 hours humidity control under constant temperature and humidity conditions of 23 ° C. and 50% RH. Note that "√ε ₁ " means the square root of _{ε 1.} ]
Is calculated based on, 23 ° C., _{E 1} value is an index showing the dielectric properties of 10GHz of the original 24-hour moisture adjustment of constant temperature and humidity conditions of RH 50% 0.010 or less, preferably 0.009 or less Is better, more preferably 0.008 or less. E ₁ values exceeds the upper limit, for example when used in a circuit board such as an FPC, is likely to occur inconveniences such as loss of electrical signals on the transmission path of the RF signal.

(Dielectric constant)
The resin film of the present embodiment is used under constant temperature and humidity conditions of 23 ° C. and 50% RH in order to ensure impedance matching when used for a circuit board such as FPC and to reduce loss of electric signals. _{The dielectric constant (ε 1} ) at 10 GHz after humidity control for 24 hours is preferably 3.2 or less, and more preferably 3.0 or less. If this dielectric constant exceeds 3.2, inconveniences such as loss of electric signals are likely to occur on the transmission path of high-frequency signals when used for a circuit board such as an FPC.

(Dissipation factor)
Further, the resin film of the present embodiment is subjected to humidity control for 24 hours under constant temperature and humidity conditions of 23 ° C. and 50% RH in order to reduce loss of electric signals when used for a circuit board such as FPC. The dielectric loss tangent (Tanδ ₁ ) at 10 GHz is preferably less than 0.005, more preferably 0.004 or less. If the dielectric loss tangent is 0.005 or more, inconveniences such as loss of electric signals are likely to occur on the transmission path of high-frequency signals when used for a circuit board such as an FPC.

(Hygroscopic dependence)
The resin film of the present embodiment has the following equation (ii), in order to reduce the loss of electric signals and ensure impedance matching during drying and wetness when used for a circuit board such as an FPC.
E ₂ = √ε ₂ × Tan δ ₂ ... (ii)
[Here, ε ₂ indicates the dielectric constant at 10 GHz measured by SPDR after water absorption at 23 ° C. for 24 hours, and Tan δ ₂ indicates the dielectric loss tangent at 10 GHz measured by SPDR after water absorption at 23 ° C. for 24 hours. Shown. Note that "√ε ₂ " means the square root of _{ε 2.} ]
_{In the E 2} value, which is an index showing the dielectric property at 10 GHz after water absorption at 23 ° C. for 24 hours, which is calculated based on the above equation (i), the ratio of the E _{2 value to the E 1} value calculated based on the above formula (i) _{(E 2).} / E ₁ ) is in the range of 3.0 to 1.0, preferably in the range of 2.5 to 1.0, and more preferably in the range of 2.2 to 1.0. If E ₂ / E ₁ exceeds the above upper limit, when used for a circuit board such as an FPC, the dielectric constant and the dielectric loss tangent in wet conditions will increase, resulting in loss of electrical signals on the transmission path of high-frequency signals. Inconveniences such as are likely to occur.

(Hygroscopicity)
Further, in the resin film of the present embodiment, in order to reduce the influence of humidity when used for a circuit board such as FPC, the hygroscopicity of the resin film is preferably 0.5% by weight or less, more preferably. It is preferably less than 0.3% by weight. Here, the "moisture absorption rate" means the moisture absorption rate after 24 hours or more have elapsed under the constant temperature and humidity conditions of 23 ° C. and 50% RH (the same meaning in the present specification). If the hygroscopicity of the resin film exceeds 0.5% by weight, it is easily affected by humidity when used for a circuit board such as an FPC, and inconveniences such as fluctuations in the transmission speed of high-frequency signals are likely to occur. That is, when the moisture absorption rate of the resin film exceeds the above range, it becomes easy to absorb water having a high dielectric constant, which causes an increase in the dielectric constant and the dielectric loss tangent, resulting in inconvenience such as loss of an electric signal on the transmission path of a high frequency signal. Is likely to occur.

(Storage modulus)
The resin film of the present embodiment may have a temperature range in which the storage elastic modulus decreases steeply as the temperature rises in the range of 40 to 250 ° C. It is considered that such characteristics of the resin film are factors that alleviate internal stresses during thermocompression bonding and maintain dimensional stability after circuit processing, for example. The resin film has a storage modulus at the upper limit temperature of the temperature range is preferably at 5 × 10 7 ^[Pa] or less. By setting such a storage elastic modulus, even if the upper limit of the temperature range is set, thermocompression bonding at 250 ° C. or lower is possible, adhesion can be ensured, and dimensional change after circuit processing can be suppressed.
Since the resin film of the present embodiment has high thermal expansion and low elasticity, it is possible to relax the internal stress generated during lamination even if the CTE exceeds 30 ppm / K.

(Glass-transition temperature)
The resin film of the present embodiment preferably has a glass transition temperature (Tg) of 250 ° C. or lower, more preferably 40 ° C. or higher and 200 ° C. or lower. When the Tg of the resin film is 250 ° C. or lower, thermocompression bonding at a low temperature becomes possible, so that the internal stress generated during lamination can be relaxed and the dimensional change after circuit processing can be suppressed. If the Tg of the resin film exceeds 250 ° C., the bonding temperature becomes high, which may impair the dimensional stability after circuit processing.

(Thickness)
The thickness of the resin film of the present embodiment is preferably in the range of, for example, 5 μm or more and 125 μm or less, and more preferably in the range of 8 μm or more and 100 μm or less. If the thickness of the resin film is less than 5 μm, problems such as wrinkles may occur during transportation in the production of the resin film, while if the thickness of the resin film exceeds 125 μm, the productivity of the resin film may decrease. There is.

[Laminate]
The laminate according to the embodiment of the present invention has a base material and an adhesive layer laminated on at least one surface of the base material, and the adhesive layer is made of the above resin film. .. The laminated body may include any layer other than the above. Examples of the base material in the laminate include a base material of an inorganic material such as a copper foil and a glass plate, and a base material of a resin material such as a polyimide film, a polyamide film, and a polyester film.
Preferred embodiments of the laminate include a coverlay film, a copper foil with a resin, and the like.

[Coverlay film]
The coverlay film, which is one aspect of the laminated body, has a coverlay film material layer as a base material and an adhesive layer laminated on one side of the coverlay film material layer, and is an adhesive layer. Is made of the above resin film. The coverlay film may contain any layer other than the above.

The material of the coverlay film material layer is not particularly limited, and for example, a polyimide-based film such as polyimide, polyetherimide, or polyamideimide, a polyamide-based film, or a polyester-based film can be used. Among these, it is preferable to use a polyimide-based film having excellent heat resistance. In addition, the coverlay film material can contain a black pigment in order to effectively exhibit light-shielding property, hiding property, design property, etc., and the surface surface is within a range that does not impair the effect of improving the dielectric property. It can contain any component such as a matte pigment that suppresses gloss.

The thickness of the coverlay film material layer is not particularly limited, but is preferably in the range of, for example, 5 μm or more and 100 μm or less.
The thickness of the adhesive layer is not particularly limited, but is preferably in the range of, for example, 10 μm or more and 75 μm or less.

The coverlay film of the present embodiment can be produced by the method exemplified below.
First, as a first method, a varnish-like polyimide composition containing a solvent is applied to one side of a film material layer for a coverlay, and then dried at a temperature of, for example, 80 to 180 ° C. to form an adhesive layer. By doing so, it is possible to form a coverlay film having a coverlay film material layer and an adhesive layer.

Further, as a second method, a varnish-like polyimide composition containing a solvent is applied onto an arbitrary base material, dried at a temperature of, for example, 80 to 180 ° C., and then peeled off for an adhesive layer. The coverlay film can be formed by forming the adhesive film of the above and heat-bonding the adhesive film to the film material layer for the coverlay at a temperature of, for example, 60 to 220 ° C.

[Copper foil with resin]
A copper foil with a resin, which is another aspect of the laminated body, is obtained by laminating an adhesive layer on at least one side of a copper foil as a base material, and the adhesive layer is made of the above resin film. The resin-coated copper foil of the present embodiment may contain any layer other than the above.

The thickness of the adhesive layer in the resin-attached copper foil is preferably in the range of, for example, 2 to 125 μm, and more preferably in the range of 2 to 100 μm. If the thickness of the adhesive layer does not reach the above lower limit value, problems such as insufficient adhesiveness cannot be ensured may occur. On the other hand, if the thickness of the adhesive layer exceeds the above upper limit value, problems such as deterioration of dimensional stability occur. Further, from the viewpoint of low dielectric constant and low dielectric loss tangent, the thickness of the adhesive layer is preferably 3 μm or more.

The material of the copper foil in the copper foil with resin is preferably one containing copper or a copper alloy as a main component. The thickness of the copper foil is preferably 35 μm or less, more preferably in the range of 5 to 25 μm. From the viewpoint of production stability and handleability, the lower limit of the thickness of the copper foil is preferably 5 μm. The copper foil may be rolled copper foil or electrolytic copper foil. Further, as the copper foil, a commercially available copper foil can be used.

The copper foil with resin may be prepared, for example, by sputtering a metal on a resin film to form a seed layer and then forming a copper layer by, for example, copper plating, or heat the resin film and the copper foil. It may be prepared by laminating by a method such as crimping. Further, in order to form an adhesive layer on the copper foil, the copper foil with resin may be prepared by casting a coating liquid of the polyimide composition, drying it to form a coating film, and then performing necessary heat treatment. Good.

[Metal-clad laminate]
(First aspect)
The metal-clad laminate according to the embodiment of the present invention includes an insulating resin layer and a metal layer laminated on at least one surface of the insulating resin layer, and at least one layer of the insulating resin layer is described above. It is made of a resin film. The metal-clad laminate of the present embodiment may include any layer other than the above.

(Second aspect)
The metal-clad laminate according to another embodiment of the present invention is formed on, for example, an insulating resin layer, an adhesive layer laminated on at least one surface of the insulating resin layer, and an insulating resin layer via the adhesive layer. It is a so-called three-layer metal-clad laminate provided with a laminated metal layer, and the adhesive layer is made of the above resin film. The three-layer metal-clad laminate may include any layer other than the above. In the three-layer metal-clad laminate, the adhesive layer may be provided on one side or both sides of the insulating resin layer, and the metal layer may be provided on one side or both sides of the insulating resin layer via the adhesive layer. Just do it. That is, the three-layer metal-clad laminate may be a single-sided metal-clad laminate or a double-sided metal-clad laminate. A single-sided FPC or a double-sided FPC can be manufactured by processing a wiring circuit by etching the metal layer of the three-layer metal-clad laminate.

The insulating resin layer in the three-layer metal-clad laminate is not particularly limited as long as it is composed of a resin having electrical insulating properties, and is, for example, polyimide, epoxy resin, phenol resin, polyethylene, polypropylene, or polytetrafluoroethylene. , Silicone, ETFE, etc., but it is preferably composed of polyimide. The polyimide layer constituting the insulating resin layer may be a single layer or a plurality of layers, but preferably includes a non-thermoplastic polyimide layer.

The thickness of the insulating resin layer in the three-layer metal-clad laminate is preferably in the range of, for example, 1 to 125 μm, and more preferably in the range of 5 to 100 μm. If the thickness of the insulating resin layer does not reach the above lower limit value, problems such as insufficient electrical insulation cannot be ensured may occur. On the other hand, if the thickness of the insulating resin layer exceeds the above upper limit value, problems such as warpage of the metal-clad laminate are likely to occur.

The thickness of the adhesive layer in the three-layer metal-clad laminate is preferably in the range of 0.1 to 125 μm, more preferably in the range of 0.3 to 100 μm. In the three-layer metal-clad laminate of the present embodiment, if the thickness of the adhesive layer does not reach the above lower limit value, there may be a problem that sufficient adhesiveness cannot be guaranteed. On the other hand, if the thickness of the adhesive layer exceeds the above upper limit value, problems such as deterioration of dimensional stability occur. Further, from the viewpoint of lowering the dielectric constant and lowering the dielectric loss tangent of the entire insulating layer, which is a laminate of the insulating resin layer and the adhesive layer, the thickness of the adhesive layer is preferably 3 μm or more.

The ratio of the thickness of the insulating resin layer to the thickness of the adhesive layer (thickness of the insulating resin layer / thickness of the adhesive layer) is preferably in the range of 0.1 to 3.0, for example, 0.15 to 2. The range of 0.0 is more preferable. With such a ratio, it is possible to suppress the warp of the three-layer metal-clad laminate. Further, the insulating resin layer may contain a filler, if necessary. Examples of the filler include silicon dioxide, aluminum oxide, magnesium oxide, beryllium oxide, boron nitride, aluminum nitride, silicon nitride, aluminum fluoride, calcium fluoride, and metal salts of organic phosphinic acid. These can be used alone or in admixture of two or more.

[Circuit board]
The circuit board according to the embodiment of the present invention is formed by wiring the metal layer of the metal-clad laminate according to any one of the above embodiments. A circuit board such as an FPC can be manufactured by processing one or more metal layers of a metal-clad laminate into a pattern by a conventional method to form a wiring layer (conductor circuit layer). The circuit board may include a coverlay film that covers the wiring layer.

Examples will be shown below, and the features of the present invention will be described in more detail. However, the scope of the present invention is not limited to the examples. In the following examples, various measurements and evaluations are as follows unless otherwise specified.

[Measuring method of amine value]
Approximately 2 g of the dimerdiamine composition is weighed in a 200-250 mL Erlenmeyer flask, using phenolphthalein as an indicator, and 0.1 mol / L ethanolic potassium hydroxide solution is added dropwise until the solution turns pale pink. , Dissolve in about 100 mL of neutralized butanol. Add 3 to 7 drops of phenolphthalein solution to it, and titrate with stirring with 0.1 mol / L ethanolic potassium hydroxide solution until the sample solution turns pale pink. Add 5 drops of bromophenol blue solution to it, and titrate with stirring with 0.2 mol / L hydrochloric acid / isopropanol solution until the sample solution turns yellow.
The amine value is calculated by the following formula (1).
Amine value = {(V ₂ x C ₂ )-(V ₁ x C ₁ )} x M _KOH / m ... (1)
Here, the amine value is a value represented by mg-KOH / g, and M _KOH has a molecular weight of potassium hydroxide of 56.1. V and C are the volumes and concentrations of the solutions used for titration, respectively, and the subscripts 1 and 2 are 0.1 mol / L ethanolic potassium hydroxide solution and 0.2 mol / L hydrochloric acid / isopropanol solution, respectively. Represents. Further, m is the sample weight expressed in grams.

[Measurement of Weight Average Molecular Weight (Mw) of Polyimide]
The weight average molecular weight was measured by a gel permeation chromatograph (manufactured by Tosoh Corporation, using HLC-8220 GPC). Polystyrene was used as the standard substance, and tetrahydrofuran (THF) was used as the developing solvent.

[Calculation of area percentage of GPC and chromatogram]
GPC prepared a sample by diluting a 100 mg solution of a 20 mg diamine diamine composition pretreated with 200 μL acetic anhydride, 200 μL pyridine and 2 mL THF with 10 mL THF (containing 1000 ppm cyclohexanone). The prepared sample was manufactured by Tosoh Corporation, trade name: HLC-8220GPC, column: TSK-gel G2000HXL, G1000HXL, flow volume: 1 mL / min, column (oven) temperature: 40 ° C., injection volume: 50 μL. Measured in. Cyclohexanone was treated as a standard substance to correct the outflow time.

At this time, the peak top of the main peak of cyclohexanone is adjusted so that the retention time is 27 minutes to 31 minutes, and the peak end is 2 minutes from the peak start of the main peak of cyclohexanone, and the peak of cyclohexanone is excluded. Each component (a) to 4 minutes and 30 seconds, with the peak top of the main peak being 18 minutes to 19 minutes and the peak start to peak end of the main peak excluding the cyclohexanone peak being 2 minutes to 4 minutes and 30 seconds. (C);
(A) Component represented by the main peak;
(B) A component represented by a GPC peak detected at a time later than the minimum value on the time side where the retention time at the main peak is late;
(C) A component represented by a GPC peak detected earlier than the minimum value on the time side where the retention time at the main peak is earlier;
Was detected.

[Evaluation of dielectric properties]
A polyimide film (cured polyimide film) is left for 24 hours under the conditions of temperature; 23 ° C. and humidity; 50% using a vector network analyzer (manufactured by Agent, trade name; vector network analyzer E8633C) and an SPDR resonator. After that, the dielectric constant (ε ₁ ) and the dielectric loss tangent (Tan δ ₁ ) at a frequency of 10 GHz were measured. Further, after absorbing water at 23 ° C. for 24 hours, the dielectric constant (ε ₂ ) and the dielectric loss tangent (Tan δ ₂ ) of the polyimide film (cured polyimide film) at a frequency of 10 GHz were measured.

[Measurement of hygroscopicity]
Two test pieces of a polyimide film (width 4 cm × length 25 cm) were prepared and dried at 80 ° C. for 1 hour. Immediately after drying, the mixture was placed in a constant temperature and humidity chamber at 23 ° C./50% RH and allowed to stand for 24 hours or more, and the weight change before and after that was calculated by the following formula.
Moisture absorption rate (% by weight) = [(weight after moisture absorption-weight after drying) / weight after drying] x 100

[Measurement of water absorption rate]
Two test pieces of a polyimide film (width 4 cm × length 25 cm) were prepared and dried at 80 ° C. for 1 hour. Immediately after drying, it was placed in pure water at 23 ° C. and allowed to stand for 24 hours or more, and the weight change before and after that was calculated by the following formula.
Water absorption rate (% by weight) = [(weight after water absorption-weight after drying) / weight after drying] x 100

[Glass transition temperature (Tg) and storage elastic modulus]
The glass transition temperature (Tg) and storage elastic modulus are 30 ° C. using a polyimide film having a size of 5 mm × 20 mm and a dynamic viscoelasticity measuring device (DMA: manufactured by UBM, trade name: E4000F). The measurement was carried out from 1 to 400 ° C. at a heating rate of 4 ° C./min and a frequency of 11 Hz. The temperature at which the elastic modulus change (tan δ) was maximized was defined as the glass transition temperature.

[Tension modulus]
The tensile elastic modulus was determined by performing a tensile test at 50 mm / min using a tension tester (manufactured by Orientec Co., Ltd., trade name Tencilon) using a test piece having a width of 12.7 mm and a length of 127 mm. Asked.

[Solder heat resistance test (drying)]
A circuit of wiring width / wiring interval (L / S) = 1 mm / 1 mm is formed by circuit processing a polyimide copper-clad laminate (manufactured by Nittetsu Chemical & Materials Co., Ltd., trade name: Espanex MB12-25-12UEG). I prepared a printed circuit board. The adhesive surface of the test piece was placed on the wiring of the printed circuit board and pressed under the conditions of a temperature of 160 ° C., a pressure of 3.5 MPa, and a time of 60 minutes. After drying this test piece with copper foil at 105 ° C, it is immersed in a solder bath set at each evaluation temperature for 10 seconds, and the adhesive state is observed to check for defects such as foaming, blistering, and peeling. did. Heat resistance is expressed by the upper limit temperature at which defects do not occur. For example, "320 ° C" means that no defects are found when evaluated in a solder bath at 320 ° C.

[Solder heat resistance test (moisture absorption)]
A circuit of wiring width / wiring interval (L / S) = 1 mm / 1 mm is formed by circuit processing a polyimide copper-clad laminate (manufactured by Nittetsu Chemical & Materials Co., Ltd., trade name: Espanex MB12-25-12UEG). I prepared a printed circuit board. The adhesive surface of the test piece was placed on the wiring of the printed circuit board and pressed under the conditions of a temperature of 160 ° C., a pressure of 3.5 MPa, and a time of 60 minutes. This test piece with copper foil was left at 40 ° C. and 80% relative humidity for 72 hours, then immersed in a solder bath set at each evaluation temperature for 10 seconds, and the adhesive state was observed to foam, blister, and peel. It was confirmed that there were no problems such as. The heat resistance is expressed by the upper limit temperature at which no defect occurs. For example, "260 ° C" means that no defect is found when evaluated in a solder bath at 260 ° C.

[Measurement of peel strength]
For the peel strength, use a Tencilon tester (manufactured by Toyo Seiki Seisakusho Co., Ltd., trade name; Strograph VE-10), and use double-sided tape on the resin layer side of a 1 mm wide sample (laminate composed of a base material / resin layer). The force was obtained when the resin layer and the base material were peeled off from each other at a speed of 50 mm / min in the 180 ° direction.

[Evaluation of warpage]
A polyimide film material with a thickness of 25 μm (manufactured by Toray DuPont, trade name; Kapton 100EN) or a copper foil with a thickness of 12 μm is coated with a polyimide solution so that the thickness after drying is 25 μm, and a test is performed. Pieces were made. In this state, place the polyimide film material or copper foil on the lower surface, measure the average of the warped heights at the four corners of the test piece, and measure 5 mm or less as "good" and 5 mm or more as "impossible". And said.

The abbreviations used in this example indicate the following compounds.
DDA1: Manufactured by Croda Japan Co., Ltd., trade name: PRIAMINE 1075 distilled and purified (a component: 98.2% by weight, b component: 0%, c component: 1.9%, amine value: 206 mg KOH / g)
DDA2: manufactured by Croda Japan Co., Ltd., trade name: PRIAMINE 1075 distilled and purified (a component: 99.2% by weight, b component: 0%, c component: 0.8%, amine value: 210 mg KOH / g)
APB: 1,3-bis (3-aminophenoxy) benzene BTDA: 3,3', 4,4'-benzophenone tetracarboxylic acid dianhydride N-12: dihydrazide dodecanedioate NMP: N-methyl-2-pyrrolidone PX-200: Phosphate ester (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; PX-200, non-halogen aromatic condensed phosphoric acid ester, phosphorus content; 9.0%)
PX-202: Phosphorus ester (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; PX-202, non-halogen aromatic condensed phosphoric acid ester, phosphorus content; 8.1%)
SR-3000: Phosphorus ester (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; SR-3000, non-halogen aromatic condensed phosphoric acid ester, phosphorus content; 7.0%)
DA-850: Phosphorus ester (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; DAIGUARD-850, non-halogen aromatic condensed phosphoric acid ester, phosphorus content; 16.0% or more)
TPP (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; TPP, non-halogen phosphate, phosphorus content; 9.5%)
TCP (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; TCP, non-halogen phosphate, phosphorus content; 8.4%)
TXP (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; TXP, non-halogen phosphate, phosphorus content; 7.6%)
CR-733 (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; CR-733S, non-halogen aromatic condensed phosphoric acid ester, phosphorus content; 10.9%)
CR-741 (manufactured by Daihachi Chemical Industry Co., Ltd., trade name; CR-741, non-halogen aromatic condensed phosphoric acid ester, phosphorus content; 8.9%)
CM-6R: Phosphorus / nitrogen compound (manufactured by Daiwa Chemical Industry Co., Ltd., trade name; furan CM-6R, average particle size 5 μm)
MC-6000: (Manufactured by Nissan Chemical Industries, Ltd., trade name; MC-6000, non-halogen melamine cyanurate)
In DDA1 and DDA2, the "%" of the b component and the c component means the area percentage of the chromatogram in the GPC measurement. The molecular weights of DDA1 and DDA2 were calculated by the following formula (1).
Molecular weight = 56.1 x 2 x 1000 / amine value ... (1)

(Synthesis Example 1)
A 1000 ml separable flask was charged with 55.51 g of BTDA (0.1721 mol), 94.49 g of DDA1 (0.1735 mol), 210 g of NMP and 140 g of xylene and mixed well at 40 ° C. for 1 hour. Then, a polyamic acid solution was prepared. This polyamic acid solution was heated to 190 ° C., heated for 10 hours, stirred, and 125 g of xylene was added to complete imidization of the polyimide solution a (solid content concentration; 30% by weight, weight average molecular weight; 82,900, Amine value; 206 mgKOH / g) was prepared.

(Synthesis Examples 2-3)
Polyimide solutions b to c were prepared in the same manner as in Synthesis Example 1 except that the raw material compositions shown in Table 1 were used.

(Production Example 1)
In 169.49 g (50 g as solid content) of the polyimide solution a obtained in Synthesis Example 1, 2.7 g of N-12 (0.0105 mol; 1 mol of BTDA ketone group) contains a primary amino group. (Equivalent to 0.35 mol) was added, 6.0 g of NMP was added to dilute the mixture, and the mixture was further stirred for 1 hour to obtain a polyimide solution 1a.

The obtained polyimide solution 1a is applied to one side of a release PET film (manufactured by Higashiyama Film Co., Ltd., trade name; HY-S05, length x width x thickness = 200 mm x 300 mm x 25 μm) and dried at 80 ° C. for 15 minutes. A polyimide film 1a'with a thickness of 25 μm was prepared by peeling from the release PET film. This polyimide film 1a'was pressed under the conditions of a temperature of 160 ° C., a pressure of 3.5 MPa, and a time of 60 minutes to obtain a polyimide film 1a.
The various evaluation results of the polyimide film 1a are as follows.
Permittivity (ε ₁ ); 2.7, _{Dissipation Factor (Tan δ 1} ); 0.0024, Permittivity (ε ₂ ); 2.7, _{Dissipation Factor (Tan δ 2} ); 0.0034, Moisture Absorption: 0.07 %, water absorption; 0.6%, Tg; 54 ℃ , 200 ℃ storage modulus; 5.0 × ¹⁰ 6 Pa, tensile modulus; 0.7 GPa, soldering heat (dry); 280 ° C., soldering heat (moisture ); 260 ° C., peel strength; 1.0 kN / m or more

(Production Examples 2 and 3)
Polyimide solutions 1b and 1c and polyimide films 1b and 1c were obtained in the same manner as in Production Example 1 except that polyimide solutions b and c were used instead of the polyimide solution a.
The various evaluation results of the polyimide films 1b and 1c are as follows.
<Polyimide film 1b>
Permittivity (ε ₁ ); 2.7, _{Dissipation Factor (Tan δ 1} ); 0.0024, Permittivity (ε ₂ ); 2.7, _{Dissipation Factor (Tan δ 2} ); 0.0034, Moisture Absorption: 0.07 %, Water absorption rate; 0.2%, Tg; 54 ° C., 200 ° C. Storage elastic modulus; Unmeasured, tensile elastic modulus; 0.7 GPa
<Polyimide film 1c>
Permittivity (ε ₁ ); 2.9, _{Dissipation Factor (Tan δ 1} ); 0.0028, Permittivity (ε ₂ ); 2.9, _{Dissipation Factor (Tan δ 2} ); 0.0052, Moisture Absorption: 0.17 %, water absorption; 0.7%, Tg; 106 ℃ , 200 ℃ storage modulus; 1.0 × less than ¹⁰ 6 Pa, tensile modulus; 1.4 GPa

[Example 1]
10 parts by weight of SR-3000 was added to the polyimide solution 1a (100 parts by weight as a solid content) obtained in Production Example 1 to obtain a polyimide composition 1. The obtained polyimide composition 1 was applied to one side of the release PET film, dried at 80 ° C. for 15 minutes, and peeled off from the release PET film to prepare a polyimide film 1'with a thickness of 25 μm.
This polyimide film 1'was heated in an oven at a temperature of 160 ° C. for 2 hours to obtain a polyimide film 1.
The various evaluation results of the polyimide film 1 are as follows.
Permittivity (ε ₁ ); 2.6, Dissipation _{factor (Tan δ 1} ); 0.0022

[Examples 2 to 16]
Each component was blended in the proportion (part by weight) shown in Table 2 to obtain polyimide compositions 2 to 16 in the same manner as in Example 1. In addition, "DDA composition" in Table 2 means a diamine diamine composition (the same is true in Table 3).

Using the obtained polyimide compositions 2 to 16, polyimide films 2 to 16 were prepared in the same manner as in Example 1.
The various evaluation results of the polyimide films 2 to 16 are as follows.
<Polyimide film 2>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0022, tensile elastic modulus; 0.7 GPa, peel strength; 1.4 kN / m
<Polyimide film 3>
Permittivity (ε ₁ ); 2.6, _{Dissipation Factor (Tan δ 1} ); 0.0020, Permittivity (ε ₂ ); 2.6, _{Dissipation Factor (Tan δ 2} ); 0.0021, Water Absorption Rate; 0.1 %, Tg; 54 ° C., tensile elastic modulus; 0.7 GPa, peel strength; 1.4 kN / m
<Polyimide film 4>
Dielectric constant (ε ₁ ); 2.6, dielectric loss tangent (Tan δ ₁ ); 0.0024, tensile elastic modulus; 0.5 GPa, peel strength; 1.5 kN / m
<Polyimide film 5>
Dielectric constant (ε ₁ ); 2.6, dielectric loss tangent (Tan δ ₁ ); 0.0022, tensile elastic modulus; 0.7 GPa
<Polyimide film 6>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0023, tensile elastic modulus; 0.1 GPa, peel strength; 1.6 kN / m
<Polyimide film 7>
Permittivity (ε ₁ ); 2.6, _{Dissipation factor (Tan δ 1} ); 0.0022, Water absorption: 0.29%, Tension elastic modulus; 0.5 GPa, Peel strength: 1.6 kN / m
<Polyimide film 8>
Permittivity (ε ₁ ); 2.7, _{Dissipation factor (Tan δ 1} ); 0.0021, Water absorption rate; 0.54%, Tension elastic modulus; 0.4 GPa, Peel strength; 1.3 kN / m
<Polyimide film 9>
Permittivity (ε ₁ ); 2.6, _{Dissipation factor (Tan δ 1} ); 0.0021, Water absorption: 0.91%, Tension elastic modulus; 0.3 GPa, Peel strength: 1.4 kN / m
<Polyimide film 10>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0020, peel strength; 0.7 kN / m
<Polyimide film 11>
Permittivity (ε ₁ ); 2.6, Dissipation _{factor (Tan δ 1} ); 0.0022
<Polyimide film 12>
Permittivity (ε ₁ ); 2.7, _{Dissipation factor (Tan δ 1} ); 0.0021
<Polyimide film 13>
Permittivity (ε ₁ ); 2.6, _{Dissipation factor (Tan δ 1} ); 0.0020
<Polyimide film 14>
Permittivity (ε ₁ ); 2.8, _{Dissipation factor (Tan δ 1} ); 0.0027
<Polyimide film 15>
Permittivity (ε ₁ ); 2.7, _{Dissipation factor (Tan δ 1} ); 0.0026
<Polyimide film 16>
Permittivity (ε ₁ ); 2.7, Dissipation _{factor (Tan δ 1} ); 0.0025

[Reference Examples 1 to 18]
Each component was blended in the proportion (part by weight) shown in Table 3 to obtain polyimide compositions 17 to 34 in the same manner as in Example 1.

Using the obtained polyimide compositions 17 to 34, polyimide films 17 to 34 were prepared in the same manner as in Example 1.
The various evaluation results of the polyimide films 17 to 34 are as follows.
<Polyimide film 17>
Permittivity (ε ₁ ); 2.7, _{Dissipation factor (Tan δ 1} ); 0.0024, Permittivity (ε ₂ ); 2.7, _{Dissipation factor (Tan δ 2} ); 0.0034, Water absorption rate; 0.2 %, Tension modulus; 0.9 GPa, peel strength; 1.2 kN / m
<Polyimide film 18>
Permittivity (ε ₁ ); 2.9, _{Dissipation factor (Tan δ 1} ); 0.0025, Tension modulus; 0.6 GPa, Peel strength; 0.4 kN / m
<Polyimide film 19>
Dielectric constant (ε ₁ ); 2.6, dielectric loss tangent (Tan δ ₁ ); 0.0031, tensile elastic modulus; 0.3 GPa
<Polyimide film 20>
Dielectric constant (ε ₁ ); 2.8, dielectric loss tangent (Tan δ ₁ ); 0.0041, tensile elastic modulus; 0.1 GPa
<Polyimide film 21>
Dielectric constant (ε ₁ ); 2.6, dielectric loss tangent (Tan δ ₁ ); 0.0028, tensile elastic modulus; 0.2 GPa
<Polyimide film 22>
Dielectric constant (ε ₁ ); 2.8, dielectric loss tangent (Tan δ ₁ ); 0.0033, tensile elastic modulus; 0.0 GPa
<Polyimide film 23>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0026, tensile elastic modulus; 0.3 GPa
<Polyimide film 24>
Dielectric constant (ε ₁ ); 2.8, dielectric loss tangent (Tan δ ₁ ); 0.0028, tensile elastic modulus; 0.0 GPa
<Polyimide film 25>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0028, tensile elastic modulus; 0.3 GPa
<Polyimide film 26>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0034, tensile elastic modulus; 0.1 GPa
<Polyimide film 27>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0027, tensile elastic modulus; 0.4 GPa
<Polyimide film 28>
Dielectric constant (ε ₁ ); 2.7, dielectric loss tangent (Tan δ ₁ ); 0.0031, tensile elastic modulus; 0.2 GPa
<Polyimide film 29>
Permittivity (ε ₁ ); 2.7, _{Dissipation factor (Tan δ 1} ); 0.0031
<Polyimide film 30>
Permittivity (ε ₁ ); 2.6, _{Dissipation factor (Tan δ 1} ); 0.0027
<Polyimide film 31>
Permittivity (ε ₁ ); 2.8, Dissipation _{factor (Tan δ 1} ); 0.0035
<Polyimide film 32>
Permittivity (ε ₁ ); 2.9, _{Dissipation factor (Tan δ 1} ); 0.0031
<Polyimide film 33>
Permittivity (ε ₁ ); 3.0, _{Dissipation factor (Tan δ 1} ); 0.0140
<Polyimide film 34>
Permittivity (ε ₁ ); 2.6, _{Dissipation factor (Tan δ 1} ); 0.0021

The above results are summarized and the evaluation results of the dielectric properties of the polyimide films 1 to 34 are shown in Tables 4 and 5.

[Example 17]
Each component was blended in the ratio (part by weight) shown in Table 2, and the polyimide composition 2 prepared in the same manner as in Example 1 was used as a polyimide film material P1 (manufactured by Toray DuPont, trade name; Kapton 50EN, frequency). It is applied to one side of a dielectric constant at 10 GHz = 3.6, a dielectric loss tangent at a frequency of 10 GHz = 0.0084, length x width x thickness = 200 mm x 300 mm x 12 μm), dried at 80 ° C. for 15 minutes, and an adhesive layer. A coverlay film 17 having a thickness of 25 μm was obtained. The warped state of the obtained coverlay film 17 was "good".

[Example 18]
The release PET film was laminated on the adhesive layer side of the coverlay film 17 so as to be in contact with the adhesive layer, and pressure-bonded with a vacuum laminator at a temperature of 160 ° C. and a pressure of 0.8 MPa for 2 minutes. Then, the polyimide composition 2 was applied to the polyimide film material P1 side of the coverlay film 17 in a state where the release PET film was pressure-bonded so that the thickness after drying was 25 μm, and dried at 80 ° C. for 15 minutes. .. Then, the polyimide composition 2 was laminated on the coated and dried surface so that the release PET film was in contact with the surface, and pressure-bonded to both sides of the polyimide film material P1 at a temperature of 160 ° C. and a pressure of 0.8 MPa for 2 minutes using a vacuum laminator. A laminate 18 having an adhesive layer was obtained.

[Example 19]
The polyimide composition 2 was applied to one side of an electrolytic copper foil having a thickness of 12 μm and dried at 80 ° C. for 15 minutes to obtain a resin-coated copper foil 19 having an adhesive layer thickness of 25 μm. The warped state of the obtained copper foil 19 with resin was “good”.

[Example 20]
The polyimide composition 2 was applied to one side of an electrolytic copper foil having a thickness of 12 μm and dried at 80 ° C. for 30 minutes to obtain a resin-coated copper foil 20 having an adhesive layer thickness of 50 μm. The warped state of the obtained resin-attached copper foil 20 was "good".

[Example 21]
The polyimide composition 2 was further applied to the surface of the adhesive layer of the resin-attached copper foil 19 and dried at 80 ° C. for 30 minutes to obtain a resin-attached copper foil 21 having a total thickness of the adhesive layer of 100 μm. The warped state of the obtained copper foil 21 with resin was “good”.

[Example 22]
The polyimide composition 2 was applied to one side of the release PET film, dried at 80 ° C. for 30 minutes, and peeled off from the release PET film to obtain a polyimide film 35 having a thickness of 50 μm.

[Example 23]
Polyimide film 2 and polyimide film material P2 (manufactured by DuPont, trade name; Kapton 100-EN, thickness 25 μm, dielectric constant at frequency 10 GHz = 3.6, dielectric tangent at frequency 10 GHz = 0) on an electrolytic copper foil with a thickness of 12 μm. .0084), Polyimide film 2 and electrolytic copper foil with a thickness of 12 μm were sequentially laminated, pressure-bonded at a temperature of 160 ° C. and a pressure of 0.8 MPa for 2 minutes using a vacuum laminator, and then heated from room temperature to 160 ° C. at 160 ° C. The copper-clad laminate 23 was obtained by heat-treating for 4 hours.

[Example 24]
Laminated on an electrolytic copper foil having a thickness of 12 μm so that the adhesive layer side of the coverlay film 17 is in contact with the copper foil, pressure-bonded at a temperature of 160 ° C. and a pressure of 0.8 MPa for 2 minutes using a vacuum laminator, and then from room temperature to 160. The temperature was raised to ° C. and heat treatment was performed at 160 ° C. for 2 hours to obtain a copper-clad laminate 24.

[Example 25]
The polyimide film 2 is laminated on the rolled copper foil having a thickness of 12 μm, laminated so that the polyimide film material P1 side of the coverlay film 17 is in contact with the polyimide film 2, and further, the thickness is 12 μm on the adhesive layer side of the coverlay film 17. Rolled copper foils are sequentially laminated, and after pressure bonding at a temperature of 160 ° C. and a pressure of 0.8 MPa for 2 minutes using a vacuum laminator, the temperature is raised from room temperature to 160 ° C. and heat treatment is performed at 160 ° C. for 2 hours. 25 was obtained.

[Example 26]
Two resin-attached copper foils 19 are prepared, and a polyimide film material P3 (manufactured by DuPont, trade name; Kapton 200-EN, thickness 50 μm, dielectric constant at a frequency of 10 GHz) is placed on the adhesive layer side of the two resin-attached copper foils 19. = 3.6, dielectric loss tangent at a frequency of 10 GHz = 0.0084), laminated so that they are in contact with each other, pressure-bonded at a temperature of 160 ° C. and a pressure of 0.8 MPa for 5 minutes using a vacuum laminator, and then raised from room temperature to 160 ° C. , Heat-treated at 160 ° C. for 4 hours to obtain a copper-clad laminate 26.

[Example 27]
The surface of the polyimide composition 2 on the resin layer side of a single-sided copper-clad laminate M1 (manufactured by Nittetsu Chemical & Materials Co., Ltd., trade name; Espanex MC12-25-00UEM, length x width x thickness = 200 mm x 300 mm x 25 μm) And dried at 80 ° C. for 30 minutes to obtain a copper-clad laminate 27 with an adhesive having an adhesive layer thickness of 50 μm. Laminated on the adhesive layer side of the copper-clad laminate 27 with adhesive so that the surface of the single-sided copper-clad laminate M1 on the resin layer side is in contact, and using a small precision press machine, the temperature is 160 ° C and the pressure is 4.0 MPa. , 120 minutes crimping to obtain a copper-clad laminate 27.

[Example 28]
A polyimide film 2 is laminated on the resin layer side of the single-sided copper-clad laminate M1, and further laminated so that the resin layer side of the single-sided copper-clad laminate M1 is in contact with the polyimide film 2, and a small precision press machine is used. The copper-clad laminate 28 was obtained by pressure bonding at a temperature of 160 ° C. and a pressure of 4.0 MPa for 120 minutes.

[Example 29]
The polyimide composition 2 was applied to one side of the release PET film, dried at 80 ° C. for 15 minutes, and the adhesive layer was peeled off from the release PET film to obtain a polyimide film 36 having a thickness of 15 μm.

[Example 30]
A double-sided copper-clad laminate M2 (manufactured by Nittetsu Chemical & Materials Co., Ltd., trade name; Espanex MB12-25-00UEG) was prepared, and the copper foil on one side was subjected to circuit processing by etching to form a conductor circuit layer. A wiring board 1A was obtained.

The copper foil on one side of the double-sided copper-clad laminate M2 was removed by etching to obtain a copper-clad laminate 1B.

The polyimide film 2 is sandwiched between the surface of the wiring board 1A on the conductor circuit layer side and the surface of the copper-clad laminate 1B on the resin layer side, and in a laminated state, the temperature is 160 ° C., the pressure is 4.0 MPa, and heat is used for 120 minutes. The multilayer circuit board 30 was obtained by crimping.

[Example 31]
Liquid crystal polymer film (manufactured by Kuraray Co., Ltd., trade name; CT-Z, thickness: 50 μm, CTE; 18 ppm / K, thermal deformation temperature: 300 ° C., dielectric constant at frequency 10 GHz = 3.40, dielectric loss tangent at frequency 10 GHz = 0 A copper-clad laminate 1C was prepared using an insulating base material and having electrolytic copper foils having a thickness of 18 μm on both sides thereof, and the copper foils on one side were subjected to circuit processing by etching to form a conductor circuit layer. The wiring board 1C in which the above was formed was obtained.

The copper foil on one side of the copper-clad laminate 1C was removed by etching to obtain a copper-clad laminate 1D.

The polyimide film 2 is sandwiched between the surface of the wiring board 1C on the conductor circuit layer side and the surface of the copper-clad laminate 1D on the insulating substrate layer side, and in a laminated state, the temperature is 160 ° C. and the pressure is 4.0 MPa. Thermocompression bonding was performed for 120 minutes to obtain a multilayer circuit board 31.

Although the embodiments of the present invention have been described in detail for the purpose of exemplification, the present invention is not limited to the above embodiments and can be modified in various ways.

Claims (11)

The following components (A) and (B);
(A) Diamine diamine containing a diamine diamine as a main component, in which two terminal carboxylic acid groups of dimer acid are replaced with a primary aminomethyl group or an amino group with respect to the tetracarboxylic acid anhydride component and the total diamine component. Polyimide obtained by reacting with a diamine component containing 40 mol% or more of the composition, and (B) aromatic condensed phosphoric acid ester,
A polyimide composition containing the above component (A) and having a weight ratio of the component (B) to the component (A) in the range of 0.05 to 0.7. The polyimide composition according to claim 1, wherein the weight ratio of the component (B) to the component (A) is in the range of 0.2 to 0.5. The polyimide composition according to claim 1 or 2, wherein the weight ratio of phosphorus derived from the component (B) to the component (A) is in the range of 0.01 to 0.1. The polyimide composition according to any one of claims 1 to 3, wherein the weight ratio of phosphorus derived from the component (B) to the diamine diamine composition in the component (A) is in the range of 0.01 to 0.15. Stuff. The polyimide composition according to any one of claims 1 to 4, further comprising an amino compound having at least two primary amino groups as functional groups. A resin film containing a polyimide layer
The polyimide layer has the following components (A) and (B);
(A) Diamine diamine containing a diamine diamine as a main component, in which two terminal carboxylic acid groups of dimer acid are replaced with a primary aminomethyl group or an amino group with respect to the tetracarboxylic acid anhydride component and the total diamine component. Polyimide obtained by reacting with a diamine component containing 40 mol% or more of the composition, and (B) aromatic condensed phosphoric acid ester,
A resin film containing the above component (A) and having a weight ratio of the component (B) to the component (A) in the range of 0.05 to 0.7. A laminate having a base material and an adhesive layer laminated on at least one surface of the base material.
A laminate characterized in that the adhesive layer is made of the resin film according to claim 6. A coverlay film having a coverlay film material layer and an adhesive layer laminated on the coverlay film material layer.
A coverlay film, wherein the adhesive layer is made of the resin film according to claim 6. A copper foil with a resin in which an adhesive layer and a copper foil are laminated.
A copper foil with a resin, wherein the adhesive layer is made of the resin film according to claim 6. A metal-clad laminate having an insulating resin layer and a metal layer laminated on at least one surface of the insulating resin layer.
A metal-clad laminate characterized in that at least one of the insulating resin layers is made of the resin film according to claim 6. A circuit board obtained by wiring processing the metal layer of the metal-clad laminate according to claim 10.