TWI644968B - Resin substrate for circuit board, resin composition for circuit board, and circuit board - Google Patents

Abstract

The present invention provides a resin substrate for a circuit board having a small relative dielectric constant (ε _r ) and a dielectric tangent (tan δ) and a small dependence of ε _r and tan δ on frequency or temperature. The resin substrate for a circuit board of the present invention contains at least a polymer (A) having a structural unit represented by the formula (1). (Ar ¹ and Ar ² are each independently an exoaryl group having 6 to 30 carbon atoms; R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms; and R ² is a direct bond, An alkanediyl group having 1 to 20 carbon atoms, -O-, -S-, or -(R ³ ₂ SiO) _a - (wherein R ^{3 is} independently an alkyl group having 1 to 20 carbon atoms, and a carbon number of 6 to An aryl group of 30 or an alkoxy group having 1 to 12 carbon atoms, and a is an integer of 1 or more; EWG is an electron-drawing group; and n is an integer of 0 or more)

Description

Resin substrate for circuit board, resin composition for circuit board, and circuit board

The present invention relates to a resin substrate which is preferably used in a circuit board, a resin composition for a circuit board, and a circuit board having the resin substrate.

In a mobile communication device typified by a mobile phone, a high-frequency electric signal is used in order to speed up the processing speed. In addition, in order to increase the speed of propagation of an electric signal, there is a method of shortening the length of the wiring by miniaturization of the semiconductor element or increasing the density of the package substrate, but by reducing the relative dielectric of the substrate itself. The constant (ε _r ) also speeds up the propagation speed. Further, the higher the frequency of the electric signal, the more easily the frequency is attenuated, and the transmission loss tends to become large. Therefore, a material having a low dielectric tangent (tan δ) in the substrate is required. Further, in order to diversify the use of the mobile communication device, it is required that ε _r or tan δ in the substrate material is small due to changes in frequency or temperature. As such a material, a substrate using liquid crystal polymer (LCP) is known (Patent Documents 1 to 2). [Prior Art Document] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2006-179609 (Patent Document 2) Japanese Patent Laid-Open No. Hei. No. 2006-137786

[Problems to be solved by the invention]

An object of the present invention is to provide a relative dielectric constant (ε _r ) and a dielectric tangent (tan δ ) having a small value, and a relative dielectric constant ( ε _r ) and a dielectric tangent (tan δ ) having little dependence on frequency and temperature. A resin substrate for a circuit board, a circuit board using the same, and a resin composition for a circuit board. [Means for solving the problem]

The present invention relates to the following [1] to [6]. [1] A resin substrate for a circuit board, comprising at least a polymer (A) having a structural unit represented by the following formula (1),

[Chemical 1] (In the formula (1), Ar ¹ and Ar ² are each independently at least one hydrogen atom having a carbon number of 6 to 30 or an aliphatic group having 6 to 30 carbon atoms, and a hydrogen atom or a halogen atom or 1 a group substituted with a valent organic group; R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms; and R ² is a direct bond, an alkanediyl group having 1 to 20 carbon atoms, or -O -, -S-, or -(R ³ ₂ SiO) _a - (wherein R ^{3 is} independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a carbon number of 1 to 12; Alkoxy group, and a is an integer of 1 or more; EWG is an electron-drawing group; n is an integer of 0 or more).

[2] The resin substrate for a circuit board according to the above [1], wherein the polymer (A) contains 50% by mass or more of the structural unit represented by the formula (1). [3] The resin substrate for a circuit board according to the above [1], wherein the difference between the Hammett substituent constant of R ¹ and EWG in the formula (1) is 0.1 to The scope of 2. [4] A resin composition for a circuit board, comprising at least a polymer (A) having a structural unit represented by the following formula (1) and an organic solvent (B);

[Chemical 2] (In the formula (1), Ar ¹ and Ar ² are each independently at least one hydrogen atom having a carbon number of 6 to 30 or an aliphatic group having 6 to 30 carbon atoms, and a hydrogen atom or a halogen atom or 1 a group substituted with a valent organic group; R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms; and R ² is a direct bond, an alkanediyl group having 1 to 20 carbon atoms, or -O -, -S-, or -(R ³ ₂ SiO) _a - (wherein R ^{3 is} independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a carbon number of 1 to 12; Alkoxy group, and a is an integer of 1 or more; EWG is an electron-drawing group; n is an integer of 0 or more).

[5] The resin composition for a circuit board according to the above [4], wherein the organic solvent (B) is selected from the group consisting of an aromatic organic solvent, a ketone organic solvent, and a guanamine organic solvent. At least one of the groups. [6] A circuit board for a circuit board according to any one of the above [1] to [3]. [Effects of the Invention]

The resin substrate for a circuit board of the present invention has a small relative dielectric constant (ε _r ), a small dielectric tangent (tan δ ) value, and a relative dielectric constant (ε _r ) and dielectric tangent (tan δ) versus frequency. And the dependence of temperature is small.

The resin composition for a circuit board of the present invention can be preferably used for the production of the resin substrate for a circuit board of the present invention. Since the circuit board of the present invention has the resin substrate for a circuit board of the present invention, it is suitable as a circuit board for precision equipment.

Hereinafter, the present invention will be specifically described. <Resin Composition for Circuit Board> The resin composition for a circuit board of the present invention contains a polymer (A) and an organic solvent (B), and is a resin composition suitable for producing a resin substrate for a circuit board.

Polymer (A) The polymer (A) has a structural unit represented by the following formula (1).

[Chemical 3] The meaning of each symbol in the formula (1) is as follows.

Ar ¹ and Ar ² are each independently substituted by a hydroxyl group, a halogen atom or a monovalent organic group, wherein at least one hydrogen atom having a carbon number of 6 to 30 or an alkyl group having 6 to 30 carbon atoms is substituted with a hydroxyl group or a monovalent organic group. base. The carbon number of the aryl group is preferably from 6 to 18, more preferably from 6 to 12.

The aryl group of Ar ¹ and Ar ² may be a single ring, a polycyclic ring, or a fused ring. Examples of the aryl group having 6 to 30 carbon atoms include a stretching phenyl group, a stretching naphthyl group, and a stretching group.

Examples of the halogen atom include a halogen atom such as a chlorine atom, a bromine atom, and a fluorine atom. Examples of the monovalent organic group include a C 1-12 alkyl group such as a methyl group, an ethyl group, a propyl group, and a decyl group; and a carbon number of 3 to 20 such as a cyclopropyl group, a cyclohexyl group, and an isobornyl group; a cycloalkyl group; an alkoxy group having 1 to 12 carbon atoms such as a methoxy group, an ethoxy group, and a butoxy group; an aryl group having 6 to 18 carbon atoms such as a phenyl group, a 1-naphthyl group, and a 2-naphthyl group; And an aryloxy group having 6 to 18 carbon atoms such as a phenoxy group. Further, the substituent which the aryl group may have selected from the group consisting of a hydroxyl group, a halogen atom and a monovalent organic group may be one type or two or more types.

R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms. In R ¹ , the alkyl group preferably has 1 to 12 carbon atoms, more preferably 1 to 4 carbon atoms, and the aryl group preferably has 6 to 18 carbon atoms, more preferably 6 to 12 carbon atoms. Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and an anthracene group. Base, and base. Examples of the aryl group having 6 to 30 carbon atoms include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, and a 1-fluorenyl group.

R ² is a direct bond, an alkyldiyl group having 1 to 20 carbon atoms, -O-, -S-, or -(R ³ ₂ SiO) _a -. Here, each of R ^{3 is} independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms, and a is an integer of 1 or more. When R ² is an alkanediyl group, the carbon number thereof is preferably from 1 to 18, more preferably from 1 to 6. Examples of the alkanediyl group having 1 to 20 carbon atoms include a methylene group, an ethane-1,2-diyl group, a propane-1,3-diyl group, a butane-1,4-diyl group, and a octyl group. Alkane-1,8-diyl. Examples of the alkyl group having 1 to 20 carbon atoms and the aryl group having 6 to 30 carbon atoms in R ³ include an alkyl group having 1 to 20 carbon atoms and a carbon number of 6 to 30 as shown in the above R ¹ . The alkoxy group having 1 to 12 carbon atoms in R ³ may be the same as the alkoxy group having 1 to 12 carbon atoms shown in the above monovalent organic group.

EWG stands for electron withdrawing group. Formula (1) as long as the EWG R ¹ is more interesting than the carbon to which R ¹ and EWG bonded electron, R is the relatively high tensile ^{electron-1-yl} can. In the above formula (1), the difference in the Hammett substituent constant between R ¹ and EWG is preferably in the range of 0.1 to 2, more preferably in the range of 0.2 to 1.5.

Examples of the EWG include a perhaloalkyl group having a carbon number of 1 to 4, a perhaloaryl group, a perhaloalkyl-substituted aryl group, a halogen atom, a cyano group, and a nitro group. The perhaloalkyl group may, for example, be a perfluoroalkyl group such as a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group or a nonafluorobutyl group, a perchloroalkyl group or a perbrominated alkyl group. Examples of the perhaloaryl group and the perhaloalkyl-substituted aryl group include a pentafluorophenyl group and a bis(trifluoromethyl)phenyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

From the viewpoint of thermal stability, preferred among the EWGs are perfluoroalkyl, perhaloaryl and perhaloalkyl substituted aryl groups, more preferably trifluoromethyl, pentafluorophenyl and bis (three) Fluoromethyl)phenyl.

n is an integer of 0 or more, and is preferably an integer of 0 to 5. The polymer (A) of the present invention may contain only one structural unit represented by the above formula (1), or may contain two or more kinds.

The polymer (A) of the present invention preferably contains 50% by mass or more of the structural unit represented by the above formula (1), more preferably 70% by mass or more of the structural unit represented by the above formula (1). Furthermore, it is more preferably 99% by mass or more of the structural unit represented by the above formula (1). The content ratio of the structural unit is a value measured by ¹ H-NMR. The polymer (A) may be used alone or in combination of two or more.

(Production Method of Polymer (A)) The polymer (A) of the present invention can be, for example, a compound represented by the following formula (a) (hereinafter also referred to as compound (a)), and the following formula, in the presence of a strong acid. The compound represented by (b) (hereinafter also referred to as compound (b)) is obtained by a polycondensation reaction.

[Chemical 4]

[Chemical 5]

[Chemical 6] In the method, it is considered that the activated carbon cation forms a polymer by directly forming a carbon-carbon bond by electrophilic attack on the aryl compound, and the activated carbon cation is formed by causing a strong acid to act on the active ketone species. generate. One-pot synthesis can be achieved by using the method, and a by-product can be synthesized which is only water and does not have a catalyst residue such as an alkali metal salt or an organometallic compound.

For details of the reaction conditions and reaction mechanism of the method, refer to "Macromolecules" 2004, 37, 6227-6235, "Macromolecules" 2008, 41, 8504-8512, "Chemical Communication ( Chem. Commun.)", 2004, 1030-1031, etc.

Compound (a) The compound (a) is represented by the following formula (a).

[Chemistry 7] In the formula (a), R ¹ and EWG have the same meanings as the same symbols in the formula (1).

Examples of the compound (a) include pentafluorophenyl methyl ketone, pentafluorophenyl ethyl ketone, trifluoromethyl methyl ketone, and 2,2,2-trifluoroacetophenone. The compound (a) may be used alone or in combination of two or more.

Compound (b) The compound (b) is represented by the following formula (b).

[化8] In the formula (b), Ar ¹ , Ar ² , R ² and n have the same meanings as the same symbols in the formula (1).

Examples of the compound (b) include aromatic hydrocarbons such as benzene, naphthalene, anthracene, p-terphenyl, p-quaterphenyl, and 9,10-diphenylfluorene; a diphenyl alkane such as diphenylethane, 1,3-diphenylpropane, 1,4-diphenylbutane or 1,8-diphenyloctane; or a diaryl ether such as diphenyl ether; a diaryl sulfide such as diphenyl sulfide; a halide such as 2-chloro-9,10-diphenylfluorene. The compound (b) may be used alone or in combination of two or more. In the polycondensation of the compound (a) and the compound (b), the aromatic ring carbon bonded to the hydrogen atom in the formula (b) is bonded to the living carbonyl carbon in the formula (a) to form a polymer.

Strong acid In the production of the polymer (A), a strong acid is used as a catalyst for the polycondensation reaction of the compound (a) and the compound (b).

Examples of the strong acid include trifluoroacetic acid, pentafluorophenylacetic acid, fluorosulfonic acid, chlorosulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, and a perfluoroalkanesulfonic acid having a carbon number of 2 or more (for example, C ₂ F ₅ SO). ₃ H, C ₄ F ₉ SO ₃ H, C ₅ F ₁₁ SO ₃ H, C ₆ F ₁₃ SO ₃ H, and C ₈ F ₁₇ SO ₃ H), pentafluorobenzenesulfonic acid, pentafluoropropionic acid. These may be used alone or in combination of two or more.

Preferable examples of the catalyst include an example in which trifluoromethanesulfonic acid is used alone, and at least one selected from the group consisting of trifluoromethanesulfonic acid and methanesulfonic acid and trifluoroacetic acid is used in combination. The total amount of the strong acid relative to one or more compounds (a) is usually from 0.01 mol to 100 mol, preferably from 0.1 mol to 50 mol.

- Polymerization solvent In the production of the polymer (A), a polymerization solvent which is inactive with respect to the strong acid or the polycondensation reaction can be used. Examples of the inactive polymerization solvent include halogenated hydrocarbons such as dichloromethane, hexachlorobenzene, and perfluorohexane (excluding compounds which are reacted in the polycondensation reaction); n-alkanes having 4 to 12 carbon atoms; An alkyl acetate such as methyl acetate, ethyl acetate or n-butyl acetate; and a fluoroalkyl ether such as a perfluoropolyether.

- Polycondensation reaction The total amount of the compound (b) to be used is usually 0.5 mol to 1.5 mol, preferably 0.9 mol to 1.1 mol, more preferably 0.95 mol to 1.05 mol, based on 1 mol of the total of the compound (a). For example, when a polycondensation reaction is carried out using one compound (a) and two compounds (b), it is preferred that the amount of the compound (a) used and the total amount of the two compounds (b) are equal to each other. Degree.

The temperature of the reaction liquid at the time of the reaction is preferably -50 ° C to 150 ° C, more preferably -30 ° C to 50 ° C. The reaction time is preferably from 0.1 to 8 hours, more preferably from 0.5 to 4 hours.

After completion of the reaction, the obtained polymer (A) can be purified by a known method. With regard to the polymerization reaction product containing the polymer (A) obtained in the above manner, since a strong acid is used as a catalyst, it is possible to contain as an impurity which is usually contained in the reactant when a general polymerization catalyst is used. The state of the inorganic salt such as copper chloride, potassium chloride or potassium carbonate is obtained. Therefore, there is a fear that deterioration is caused by inorganic salts remaining as impurities, and there is no need to utilize an complicated step to remove impurities from the polymerization reactant.

Characteristics of the polymer (A) The polystyrene-equivalent weight average molecular weight (Mw) measured by a gel permeation chromatography (GPC) method is preferably 10,000 to 1,000,000 with respect to the polymer (A) of the present invention. More preferably, it is 30,000 to 200,000. Further, the molecular weight distribution (Mw/Mn) is preferably from 1.0 to 4.0, more preferably from 1.0 to 3.0. The molecular weight can be adjusted, for example, by the amount of strong acid used.

The glass transition temperature (Tg) of the polymer (A) of the present invention measured by differential scanning calorimetry (DSC) is preferably from 170 ° C to 350 ° C, more preferably from 200 ° C to 300 ° C. The thermal decomposition temperature (5% weight reduction temperature) measured by Thermal Gravity Analysis (TGA) of the polymer (A) of the present invention is preferably 350 ° C or higher, more preferably 380 ° C or higher. The upper limit is not particularly limited and is, for example, 550 °C.

In the case where the polymer (A) of the present invention has a structural unit represented by the above formula (1), it is formed into a film shape, a sheet shape, or the like, and the value of the relative dielectric constant (? _r ) is small. The value of electrical tangent (tan δ) is small, and the relative dielectric constant (ε _r ) and dielectric tangent (tan δ) are less dependent on frequency and temperature. The reason for this is presumed to be that the polarization of the polymer (A) in the short axis direction (the direction perpendicular to the main chain of the polymer) is small, and the portion generated by the polarization is a four-stage carbon structure, so that the molecules are difficult to rotate. Therefore, the polymer (A) of the present invention is particularly suitable for use in the production of a resin substrate for a circuit board.

Organic solvent (B) The organic solvent (B) is a solvent which dissolves the polymer (A), and is a solvent for making a resin composition for a circuit board easy to handle. A circuit board on a circuit board with a resin composition formed a small value ε _r and tanδ with a resin substrate, and thus may be formed of the ε _r tanδ and the circuit board or less temperature dependence of frequency with respect resin substrate The organic solvent (B) is preferably at least one selected from the group consisting of an aromatic organic solvent, a ketone organic solvent, and a guanamine organic solvent. The organic solvent (B) may be used alone or in combination of two or more.

Examples of the aromatic organic solvent include anisole, toluene, mesitylene, and xylene. Examples of the ketone organic solvent include 2-heptanone, 3-heptanone, 4-heptanone, and cyclohexanone. Examples of the amide-based organic solvent include 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, and 3-hexyloxy group. -N,N-dimethylpropanamide, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N-methyl- 2-pyrrolidone, N-vinyl-2-pyrrolidone, N-pentyl-2-pyrrolidone, N-(methoxypropyl)-2-pyrrolidone, N-(third Alkyl-2-pyrrolidone, and N-cyclohexyl-2-pyrrolidone.

From the viewpoints of coatability and economy, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, toluene and mesitylene can be more preferably used. The content ratio of the polymer (A) in the resin composition for a circuit board of the present invention is usually from 1% by mass to 40% by mass, preferably from 5% by mass to 25% by mass. When the content ratio of the polymer (A) in the composition is in the above range, thick film formation can be achieved in the case of forming a coating film, and therefore, a resin for a circuit board which is less likely to cause pinholes and has excellent surface smoothness can be formed. Substrate.

Other components In addition to the polymer (A) and the organic solvent (B), the resin composition for a circuit board of the present invention may contain other components within a range not impairing the object of the present invention. Examples of other components which may be contained in the resin composition for a circuit board of the present invention include inorganic particles, a resin component other than the polymer (A), a flame retardant, an anti-aging agent, a heat stabilizer, an antioxidant, and ultraviolet rays ( Ultraviolet, UV) absorbents, surfactants, lubricants, and fillers.

The inorganic particles are used to impart low thermal expansion property to the resin substrate for a circuit board formed of the resin composition for a circuit board. Examples of the material of the inorganic particles include cerium oxide, aluminum hydroxide, aluminum oxide, E glass, S glass, D glass, H glass, boron nitride, aluminum nitride, kaolin, talc, mica, and clay. , magnesium hydroxide, molybdenum oxide, titanium oxide, zinc oxide, barium titanate. The particle diameter of the inorganic particles is usually from 0.1 μm to 100 μm.

Γ-glycidyloxy can be used in order to uniformly disperse the resin composition for a circuit board and to improve the heat resistance of the resin substrate for a circuit board formed of the resin composition for a circuit board. A decane coupling agent such as propyltrimethoxydecane, γ-glycidoxypropylmethyldiethoxysilane or γ-methylpropoxypropyltrimethoxydecane is surface-treated.

A resin component other than the polymer (A) is used to impart a function other than the function derived from the polymer (A). Examples of the resin component other than the polymer (A) include ethylene, propylene, butadiene, isoprene, styrene, divinylbenzene, methacrylic acid, acrylic acid, methacrylic acid ester, and acrylate. , a single polymer of a vinyl compound such as vinyl chloride, acrylonitrile, maleic anhydride, vinyl acetate or tetrafluoroethylene, and a copolymer of two or more vinyl compounds, polyamine, polyimine, polycarbonate , thermoplastic resins such as polyester, polyacetal, polyphenylene sulfide, and polyethylene glycol; and phenol resin, epoxy resin, and cyanate resin.

The flame retardant is a flame retardant which imparts flame retardancy to a resin substrate for a circuit board formed of a resin composition for a circuit board, and examples thereof include inorganic oxides such as antimony trioxide, aluminum hydroxide, magnesium hydroxide, and zinc borate. An aromatic bromine compound such as hexabromobenzene, decabromodiphenylethane, and ethyl bis-tetrabromophthalimide.

The anti-aging agent is used to further improve the durability of the resin substrate for a circuit board formed of the resin composition for a circuit board, and examples thereof include a hindered phenol-based compound.

Method for Producing Resin Composition for Circuit Board The resin composition for a circuit board of the present invention can be produced by uniformly mixing the components. Further, in order to remove the waste residue, the components may be uniformly mixed, and the resulting mixture may be filtered by a filter or the like.

The resin composition for a circuit board of the present invention has a viscosity of usually 50 mPa·s to 100,000 mPa·s, preferably 500 mPa·s to 50,000 mPa·s, more preferably 1,000 mPa·s to 20,000 mPa·s. The viscosity is a value measured by a rotational viscometer according to Japanese Industrial Standards (JIS) K7117. When the viscosity of the resin composition for a circuit board is in the above range, the retention of the composition during film formation such as formation of a coating film is excellent, and the thickness can be easily adjusted. Therefore, a desired resin substrate for a circuit board can be easily molded. .

<Resin substrate for circuit board> The resin substrate for a circuit board of the present invention contains the polymer (A). Since the resin substrate for a circuit board of the present invention contains the polymer (A), the relative dielectric constant (ε _r ) and the dielectric tangent (tan δ ) are small, and the relative dielectric constants (ε _r ) and A resin substrate for a circuit board having a small tanner (tan δ) dependence on frequency and temperature.

The resin substrate for a circuit board of the present invention can be produced by any method as long as it contains the polymer (A), but is preferably produced by the resin composition for a circuit board of the present invention. In the method of producing a resin substrate for a circuit board from the resin composition for a circuit board of the present invention, the resin component for the circuit board can be produced by removing the volatile component from the resin composition for the circuit board, for example, by using a circuit. After the resin composition for a substrate is applied onto a support to form a coating film, or the resin composition for a circuit board is impregnated into the reinforcing fiber substrate, the volatile component such as the organic solvent (B) is removed to produce a circuit board. Resin substrate.

Examples of the coating method include a roll coating method, a gravure coating method, a spin coating method, a slit coating method, and a method using a doctor blade. Examples of the support include a polyethylene terephthalate (PET) film and a SUS plate. The thickness of the coating film may be appropriately determined depending on the film thickness of the resin substrate for a circuit board finally obtained, and is usually 1 μm to 1000 μm.

When the resin composition for a circuit board is impregnated on the reinforcing fiber base material, examples of the reinforcing fiber base material include a roving cloth, a cloth, a chopped mat, and a surface felt. Surfacing mat) and other glass cloth; asbestos cloth, metal fiber cloth, and other synthetic or natural inorganic fiber cloth; liquid crystal fiber such as wholly aromatic polyamide fiber, wholly aromatic polyester fiber, polybenzoxazole fiber The obtained woven or non-woven fabric; natural fiber cloth such as cotton cloth, linen cloth, felt, etc.; natural cellulose such as carbon fiber cloth, craft paper, cotton paper, cloth obtained from paper-glass hybrid fiber a substrate; a polytetrafluoroethylene porous membrane. The reinforcing fiber base materials may be used alone or in combination of two or more.

As a method of removing a volatile component, such as the organic solvent (B), the heating method is mentioned, for example. The heating conditions are usually carried out at a temperature of from 30 ° C to 300 ° C for 10 minutes to 5 hours. Furthermore, heating of two or more stages can also be performed. Specifically, it is dried at a temperature of 30 ° C to 80 ° C for 10 minutes to 2 hours, and further heated at 100 ° C to 250 ° C for 10 minutes to 3 hours. Further, it may be dried under a nitrogen atmosphere or under reduced pressure as needed.

When the coating film is applied to the support to form a coating film, the obtained resin substrate may be peeled off from the support and used as a resin substrate for a circuit board, or may be used as a resin substrate for a circuit board without being peeled off from the support.

In addition, when the resin composition for a circuit board is impregnated on the reinforcing fiber base material, the content of the polymer (A) contained in the obtained resin substrate for a circuit board is 30% by mass or more, preferably 30% by mass to ～ 80% by mass, more preferably 40% by mass to 70% by mass.

The thickness of the resin substrate for a circuit board of the present invention can be appropriately selected depending on the intended use, and is usually 1 μm to 250 μm, preferably 2 μm to 150 μm, and more preferably 5 μm to 125 μm. The amount of the residual solvent in the resin substrate is usually 0% by weight to 1.2% by weight, preferably 0% by weight to 1% by weight based on 100% by weight of the resin substrate for a circuit board. By the amount of residual solvent being in the range, the relative dielectric constant (ε _r ) and the value of the dielectric tangent (tan δ) are small, and the relative dielectric constant (ε _r ) and the dielectric tangent (tan δ) pair are obtained. A resin substrate for a circuit board having a low frequency and temperature dependency.

The resin substrate for a circuit board of the present invention has a tensile strength of usually 50 MPa to 400 MPa, and an elongation at break of usually 5% to 100%, and a tensile modulus of elasticity of usually 2.5 GPa to 4.0 GPa, and a linear expansion coefficient is usually It is below 80 ppm/K and the humidity expansion coefficient is usually 15 ppm/% RH or less.

The tensile strength and the tensile modulus are values calculated according to JIS K 7161, the elongation at break is a value calculated according to JIS Z 2241:2011, and the coefficient of linear expansion is a value calculated according to JIS Z 2285:2003, and the humidity is expanded. The coefficient is a value calculated using the dimensional change rate (%) with respect to the change rate (%) of the relative humidity.

<Circuit Substrate> The circuit board of the present invention has the resin substrate for a circuit board of the present invention, and is provided by providing a wiring portion on one surface or both surfaces of the resin substrate for a circuit board. Such a circuit board has a small relative dielectric constant (ε _r ), a small dielectric tangent (tan δ) value, and a relative dielectric constant (ε _r ) and a dielectric tangent (tan δ) dependence on frequency and temperature. Since the resin substrate for a circuit board of the present invention having a small amount is small, the transmission speed is large and the transmission loss is small, so that it can be preferably used in a high frequency region.

The method of forming the wiring portion can be formed on the resin substrate for a circuit board by, for example, a buildup method, a metallization method, a sputtering method, a vapor deposition method, a coating method, a printing method, or the like. A conductive layer of a conductive material such as copper, indium tin oxide (ITO), polythiophene, polyaniline or polypyrrole, and the conductive layer is patterned to form a wiring portion. In addition, in order to improve the adhesion between the resin substrate for the circuit board and the conductive layer, the surface of the resin substrate for the circuit board may be modified by plasma treatment or the like before the formation of the conductive layer, or the adhesive may be applied to the circuit. On the resin substrate for the substrate. [Examples]

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to the examples. In the following description of the examples and the like, "parts" are used in the sense of "parts by mass" unless otherwise specified.

<Measurement and Evaluation Method> Weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn) of the resin The weight average molecular weight (Mw) and the number average molecular weight were measured by gel permeation chromatography under the following conditions ( Mn), and molecular weight distribution. • Pipe column: "TSKgel αM" and "TSKgel α2500", which are manufactured by Tosoh Corporation, are connected in series. Solvent: N-methyl-2-pyrrolidone with lithium bromide and phosphoric acid added. Temperature: 40°C ·Test method: refractive index method·standard material: polystyrene·GPC device: manufactured by Tosoh Corporation, device name “HLC-8020-GPC”

The structure analysis structure was analyzed by ¹ H-NMR under the following conditions. ·Device: manufactured by Japan Electron Optics Laboratory (JEOL), the device name is "ECP-400P" · Deuterated solvent: Selecting the solubility in deuterated solvent selected from deuterated chloroform, deuterated methanol and heavy water The highest generation of solvent.

Glass transition temperature (Tg), thermal decomposition temperature The glass transition temperature (Tg) of the polymer was measured at a temperature increase rate of 20 ° C / min using a Model 8230 DSC measuring apparatus manufactured by Rigaku Corporation. Further, the 5% weight loss temperature of the polymer was measured by a thermogravimetric analysis (TAG) at a temperature increase rate of 10 ° C / min under a nitrogen atmosphere, and this was taken as the thermal decomposition temperature of the polymer.

Dielectric properties (relative dielectric constant (ε _r ) and dielectric tangent (tan δ)) The film for evaluation was used, and the device name "FPR-110" manufactured by KEYCOM was used, and the perturbation mode resonance method was used. To determine the temperature conditions (23 ° C, 40 ° C, 85 ° C, and 100 ° C), frequency conditions (1 GHz, 10 GHz, and 100 GHz), and relative humidity (45 RH, 50 RH, and 85 RH) Relative dielectric constant (ε _r ) and dielectric tangent (tan δ).

[Example 1] Production of polymer (A-1) A 300 mL three-necked flask equipped with a stirrer and a three-way cock with a nitrogen introduction tube was used, and the inside was purged with nitrogen, and 10.28 g of 2, 2 was added. 2-Trifluoroacetophenone, 10.04 g of diphenyl ether, and 50 mL of methyl chloride.

Then, 27.14 g of trifluoromethanesulfonic acid was added, and stirring was started, and the reaction was carried out at -20 ° C for 3 hours. After completion of the reaction, the reaction solution was poured into methanol to precipitate a reactant, and the filtrate was separated. The obtained filtrate was vacuum dried at 60 ° C overnight to obtain a white powder of the polymer (A-1). The yield was 18.30 g and the yield was 95%.

The obtained polymer (A-1) had Mw of 86,000, Mw/Mn of 2.7, Tg of 220 ° C, and thermal decomposition temperature of 510 °C. From the ¹ H-NMR spectrum (Fig. 1) of the obtained polymer (A-1), it was confirmed that the obtained polymer had a structural unit of the following formula.

[Chemistry 9]

-Production of Resin Substrate The polymer (A-1) obtained in the above was dissolved in N,N-dimethylacetamide (DMAc) to obtain a polymer concentration of 20% by mass. Resin composition. The resin composition was applied onto a support comprising polyethylene terephthalate (PET) using a doctor blade, dried at 70 ° C for 30 minutes, and then dried at 100 ° C for 30 minutes. After film formation, the self-supporting body is peeled off. Then, the film was fixed on a metal frame, and further dried at 180 ° C for 2 hours to obtain a film-shaped resin substrate having a film thickness of 30 μm. The obtained film-form resin substrate was used as a sample for evaluation, and dielectric characteristics were evaluated. The evaluation results are shown in Table 1.

[Example 2] Production of polymer (A-2) A 300 mL three-necked flask equipped with a stirrer and a three-way cock with a nitrogen introduction tube was used, and the inside was purged with nitrogen, and 5.49 g of 2, 2 was added. 2-Trifluoroacetophenone, 2.55 g of diphenyl ether, 3.45 g of conjugated triphenyl, and 50 mL of chlorinated methane.

Then, 16.96 g of trifluoromethanesulfonic acid was added, and stirring was started, and the reaction was allowed to proceed at -20 ° C for 5 hours. After completion of the reaction, the reaction solution was poured into methanol to precipitate a reactant, and the filtrate was separated. The obtained filtrate was vacuum dried at 60 ° C overnight to obtain a white powder of the polymer (A-2). The yield was 10.56 g and the yield was 96%.

The obtained polymer (A-2) had Mw of 102,000, Mw/Mn of 2.8, Tg of 290 ° C, and thermal decomposition temperature of 512 °C. From the ¹ H-NMR spectrum (Fig. 2) of the obtained polymer (A-2), it was confirmed that the obtained polymer had a structural unit of the following formula.

[化10]

- Resin substrate production A resin substrate was produced in the same manner as in Example 1 except that the polymer (A-2) obtained in the above was used instead of the polymer (A-1), and a film having a film thickness of 30 μm was obtained. Resin substrate. The obtained film-form resin substrate was used as a sample for evaluation, and dielectric characteristics were evaluated. The evaluation results are shown in Table 1.

[Example 3] Production of polymer (A-3) A 300 mL three-necked flask equipped with a stirrer and a three-way cock with a nitrogen introduction tube was used, and the inside was purged with nitrogen, and 3.53 g of 2, 2 was added. 2-Trifluoroacetophenone, 0.51 g of diphenyl ether, 6.22 g of conjugated triphenyl, and 50 mL of chlorinated methane.

Then, 16.96 g of trifluoromethanesulfonic acid was added, and stirring was started, and the reaction was allowed to proceed at -20 ° C for 5 hours. After completion of the reaction, the reaction solution was poured into methanol to precipitate a reactant, and the filtrate was separated. The obtained filtrate was vacuum dried at 60 ° C overnight to obtain a white powdery polymer (A-3). The yield was 10.56 g and the yield was 96%.

The obtained polymer (A-3) had a Mw of 76,000, a Mw/Mn of 2.6, a Tg of 330 ° C, and a thermal decomposition temperature of 505 °C. From the ¹ H-NMR spectrum of the obtained polymer (A-3), it was confirmed that the obtained polymer (A-3) had a structural unit of the following formula.

[11]

- Production of Resin Substrate A resin substrate was produced in the same manner as in Example 1 except that the polymer (A-3) obtained in the above was used instead of the polymer (A-1), and a film having a film thickness of 30 μm was obtained. Resin substrate. The obtained film-form resin substrate was used as a sample for evaluation, and dielectric characteristics were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 1] A polyimide film (trade name "Kapton 100H/V", manufactured by Toray DuPont Co., Ltd., film thickness: 25 μm) was used as a sample for evaluation, and dielectric properties were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 2] A liquid crystal polymer film (trade name "Bextor CT-Z", manufactured by Kuraray Co., Ltd., film thickness: 25 μm) was used as a sample for evaluation, and dielectric properties were evaluated. . The evaluation results are shown in Table 1.

[Table 1] [Industrial availability]

The resin substrate for a circuit board of the present invention can be preferably used for the production of various circuit boards. Further, the resin composition for a circuit board of the present invention can be preferably used for the production of a resin substrate for a circuit board. The circuit board of the present invention is suitable for use as a circuit board for precision machinery.

no

Fig. 1 shows a ¹ H-Nuclear Magnetic Resonance (NMR) spectrum of the polymer (A-1) obtained in Example 1. Fig. 2 shows a ¹ H-NMR spectrum of the polymer (A-2) obtained in Example 2.

Claims (8)

A resin substrate for a circuit board, comprising at least a polymer (A) having a structural unit represented by the following formula (1), In the formula (1), Ar ¹ and Ar ² are each independently at least one hydrogen atom having a carbon number of 6 to 30 or an alkyl group having 6 to 30 carbon atoms, which is a hydroxyl group, a halogen atom or a monovalent group. a group substituted with an organic group; R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms; and R ² is a direct bond, an alkanediyl group having 1 to 20 carbon atoms, and -O- , -S-, or -(R ³ ₂ SiO) _a - wherein R ^{3 is} independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or an alkyl group having 1 to 12 carbon atoms An oxy group, wherein a is an integer of 1 or more; EWG is an electron-withdrawing group; and n is an integer of 0 or more. The resin substrate for a circuit board according to the first aspect of the invention, wherein the R ¹ is an aryl group having 6 to 30 carbon atoms, and the R ² is a direct bond or -O-. The resin substrate for a circuit board according to the first aspect of the invention, wherein the polymer (A) contains 50% by mass or more of the structural unit represented by the formula (1). In the resin substrate for a circuit board according to the first or second aspect of the invention, the difference between the Hamid substituent constants of R ¹ and EWG in the formula (1) is in the range of 0.1 to 2. A resin composition for a circuit board, comprising at least a polymer (A) having a structural unit represented by the following formula (1) and an organic solvent (B); In the formula (1), Ar ¹ and Ar ² are each independently at least one hydrogen atom having a carbon number of 6 to 30 or an alkyl group having 6 to 30 carbon atoms, which is a hydroxyl group, a halogen atom or a monovalent group. a group substituted with an organic group; R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms; and R ² is a direct bond, an alkanediyl group having 1 to 20 carbon atoms, and -O- , -S-, or -(R ³ ₂ SiO) _a - wherein R ^{3 is} independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or an alkyl group having 1 to 12 carbon atoms An oxy group, wherein a is an integer of 1 or more; EWG is an electron-withdrawing group; and n is an integer of 0 or more. The resin composition for a circuit board according to claim 5, wherein the R ¹ is an aryl group having 6 to 30 carbon atoms, and the R ² is a direct bond or -O-. The resin composition for a circuit board according to claim 5, wherein the organic solvent (B) is selected from the group consisting of aromatic organic solvents and ketones. It is at least one of a group consisting of an organic solvent and a guanamine-based organic solvent. A circuit board for a circuit board according to any one of the first to fourth aspects of the invention.