JP2003082063A - Epoxy resin composition for electronic material and low dielectric electronic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating and drying method including an active ester compound having excellent solvent solubility and easy mixing with an epoxy resin as a curing agent in addition to excellent heat resistance and low dielectric constant. Epoxy resin composition for electronic material that can be easily impregnated into equipment, low dielectric electronic material having excellent low dielectric and heat resistance made of cured product thereof, and sheet and laminate made of the low dielectric electronic material I will provide a. SOLUTION: Epoxy resin having two or more epoxy groups in one molecule, epoxy resin composition for electronic material containing di (α-naphthyl) isophthalate and a curing accelerator as essential components, epoxy for electronic material Low dielectric electronic material having a dielectric loss tangent of less than 1.0 × 10 ^{−2 at} 1 GHz, made of a cured resin composition, a sheet made of the low dielectric electronic material, and a metal foil on one or both surfaces of the sheet A copper-clad laminate having.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an epoxy resin composition for electronic materials and a low dielectric electronic material comprising a cured product thereof. More specifically, an epoxy resin composition for electronic materials having excellent low dielectric loss tangent, adhesion, solder resistance, and curability, and a low dielectric electronic material comprising a cured product of the epoxy resin composition for electronic materials, Further, the present invention relates to, for example, a sheet or a laminated board using the low dielectric electronic material. The low dielectric electronic material of the present invention is particularly preferably used as an adhesive resin for electronic materials, a resin for printed wiring boards, and a low dielectric electronic material for forming other electronic parts.

[0002]

2. Description of the Related Art Epoxy resins, which are excellent in electrical properties, mechanical properties, adhesiveness, etc., have hitherto been widely used for laminated boards, printed boards and the like. In recent years, with the advent of the advanced information society and the enormous amount of information, the speeding up of signals and high-frequency communication are indispensable, and the improvement of transmission characteristics is required. Insulating materials with low dielectric constant and dielectric loss tangent are required. Is desired. Especially for communication, reduction of the dielectric loss tangent is extremely important.

However, in a normal epoxy resin, ring-opening of an epoxy group occurs in a reaction with a curing agent such as a phenol compound or an amine compound, and a hydroxyl group having high polarity is generated accordingly, so that the dielectric constant and the dielectric loss tangent are increased. Was difficult to reduce. When an acid anhydride is used as the curing agent for the epoxy resin, hydroxyl groups do not occur except at the terminal where the reaction stops in the curing reaction of the epoxy resin, but the fat composition easily opens the ring due to moisture absorption. The desired low dielectric material could not be obtained since it gives an acid.

In recent years, as a curing agent for epoxy resins, a compound called an active ester compound, which reacts with an epoxy group at the time of ring opening of the epoxy group in the curing reaction of the epoxy resin and does not form a highly polar hydroxyl group, has been reported. Has been done. For example, in JP-A-61-227844, a monoester having an electron-withdrawing group on phenoxy or benzoate is effective as an active ester compound, and is used together with a side chain epoxy group-containing polymer and an addition reaction catalyst for the ester compound. Is disclosed.

Japanese Patent Publication No. 4-8444 describes a large number of active ester compounds composed of a combination of a polycarboxylic acid and various hydroxy compounds including naphthols, and the epoxy group ring-opening in the curing reaction of an epoxy resin. At the time of
It is disclosed that the active ester compound undergoes an addition reaction with an epoxy group and a hydroxyl group having a high polarity is not generated at all, so that it is possible to avoid deterioration of electric characteristics of an epoxy resin cured product.

Further, JP-A-11-71499 and JP-A-11-715.
In 00 and JP-A-11-130939, an epoxy resin cured product using a compound containing an active ester group as a curing agent for an epoxy resin is proposed as a low dielectric constant material. However, the compounds containing an active ester group described in these publications have a phenolic hydroxyl group in addition to the active ester group in the molecule, and the obtained epoxy resin cured product had a dielectric constant of 3.6 or more.

[0007] In Japanese Patent Publication No. 4-8444 mentioned above, a large number of active ester compounds comprising a combination of a polyvalent carboxylic acid and various hydroxy compounds including naphthols are described. An ester compound, for example, an active ester composed of an aliphatic polycarboxylic acid having an alkylene chain such as adipic acid or sebacic acid has excellent solvent solubility but low heat resistance. On the other hand, a wholly aromatic ester composed of an aromatic polyvalent carboxylic acid such as terephthalic acid or trimesic acid has excellent heat resistance, but its solubility in an organic solvent is extremely low, and mixing with an epoxy resin, coating drying,
There was a processing problem that impregnation was difficult.

[0008]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to provide an active ester compound having excellent heat resistance and low dielectric property as well as excellent solvent solubility and easy mixing with an epoxy resin. Epoxy resin composition for electronic material, which is easy to be dried by coating and impregnated into an inorganic material, which is contained as a curing agent, a low dielectric electronic material having excellent low dielectric property and heat resistance, and a low dielectric electronic material comprising the cured product. It is to provide sheets and laminates of dielectric electronic materials.

[0009]

As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have contained two active ester groups consisting of isophthalic acid and α-naphthol as a curing agent for epoxy resins. It was found that the wholly aromatic compound described above gives an epoxy resin cured product which is particularly excellent in solvent solubility and also has a low dielectric loss tangent and a low dielectric constant and excellent heat resistance, and has completed the present invention.

That is, according to the present invention, an epoxy resin (A) having two or more epoxy groups in one molecule, di (α-naphthyl) isophthalate (B) and a curing accelerator (C).
Provided is an epoxy resin composition for electronic materials, which comprises as an essential component.

In the present invention, an electron containing as essential components an epoxy resin (A) having two or more epoxy groups in one molecule, di (α-naphthyl) isophthalate (B) and a curing accelerator (C). Provided is a low dielectric electronic material having a dielectric loss tangent of less than 1.0 × 10 ^{−2 at} 1 GHz, which is composed of a cured product of an epoxy resin composition for materials.

Further, the present invention provides a sheet made of the low dielectric electronic material and a copper clad laminate having a metal foil on one side or both sides of the sheet.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy resin (A) having two or more epoxy groups in one molecule used in the present invention is specifically, for example, cresol novolac, phenol novolac, naphthol modified novolac, bisphenol-
A, bisphenol-F, tetrabromobisphenol-A, biphenyl type epoxy resin, triphenyl type epoxy resin, phenol type glycidyl ether type epoxy resin such as tetraphenyl type epoxy resin, polypropylene glycol, alcohol such as hydrogenated bisphenol-A Glycidyl ether type epoxy resin,

Dicyclopentadiene type epoxy resin containing dicyclopentadiene skeleton, naphthalene type epoxy resin containing naphthalene skeleton, glycidyl ester type epoxy resin made from hexahydrophthalic anhydride, dimer acid, etc., polyamines such as diaminodiphenylmethane Examples thereof include glycidyl amine type epoxy resins, alicyclic type epoxy resins, brominated epoxy resins and mixtures thereof.

Among them, in order to obtain good heat resistance, cresol novolac type epoxy resin, phenol novolac type epoxy resin, naphthol modified novolac type epoxy resin, bisphenol type epoxy resin, biphenyl type epoxy resin, triphenyl type epoxy resin. ,
A mixture of one or more epoxy resins selected from the group consisting of tetraphenyl-type epoxy resins, dicyclopentadiene-type epoxy resins, naphthalene-type epoxy resins, and brominated epoxy resins is preferable, and the epoxy equivalent is 100.
~ 1000 (g / eq), preferably 200-500
(G / eq) epoxy resin may be used. Among them, the dicyclopentadiene type epoxy resin is particularly preferable in terms of achieving both low dielectric property and heat resistance.

Next, the di (α-naphthyl) isophthalate (B) used in the present invention will be described. Di (α-naphthyl) isophthalate (B) is a wholly aromatic ester compound represented by structural formula (1). Structural formula (1)

[0017]

[Chemical 1]

The characteristic feature of the epoxy resin composition for electronic materials of the present invention is that the specific wholly aromatic active ester, di (α-α), has a very high solubility in an organic solvent while having high heat resistance and low dielectric properties. Naphthyl) isophthalate (B) is included as a curing agent.

By using di (α-naphthyl) isophthalate (B) as the curing agent, it is possible to suppress the free acid generated by hydrolysis when the epoxy resin composition is cured, so that the low dielectric constant is achieved. Is effective for ensuring the above-mentioned effect and the active ester is a wholly aromatic ester compound containing no alkylene chain, and therefore has excellent heat resistance. In the present invention, "heat resistance" means that the glass transition temperature is 1
Above 10 ℃, the coefficient of linear thermal expansion is 60 × 10 ^-6 (1 / ℃)
It means that it can withstand a solder bath immersion test at 300 ° C.

Further, di (α-naphthyl) isophthalate can be used in various organic solvents such as N-methylpyrrolidone, N, N'-dimethylformamide, N, which can dissolve both the epoxy resin and the curing accelerator in a homogeneous manner. It has a high solubility in solvents such as N'-dimethylacetamide, cyclohexanone, tetrahydrofuran, 1,3-dioxolane, toluene.

That is, surprisingly, di (α-naphthyl) isophthalate was dissolved in N-methylpyrrolidone in an amount of 50% by weight or more at 25 ° C. to give N, N′-dimethylformamide and N, N′-dimethylacetamide. , 40% by weight or more is dissolved in cyclohexanone, tetrahydrofuran and the like.

When the compound having a phenolic hydroxyl group, which is a constituent of the active ester group-containing compound, is β-naphthol, or when the aromatic compound having a polycarboxylic acid is terephthalic acid or naphthalenedicarboxylic acid,
Solubility in the above-mentioned organic solvent decreases to 10% by weight or less. From this, among the wholly aromatic ester compounds having two active ester groups, di (α-naphthyl) isophthalate, which is composed of isophthalic acid and α-naphthol, is an exceptional compound which is extremely specific and excellent in solvent solubility. It is clear.

Next, a method for producing di (α-naphthyl) isophthalate will be described. Examples of the synthesis method of di (α-naphthyl) isophthalate include acetic anhydride method, interfacial polymerization method,
Conventionally known synthetic methods such as the direct method can be mentioned.

In the acetic anhydride method, for example, a method of obtaining di (α-naphthyl) isophthalate by acetylating the phenolic hydroxyl group of α-naphthol with an excess of acetic anhydride and then performing a deacetic reaction with isophthalic acid is carried out. Can be mentioned. The amount of acetic anhydride is preferably equimolar or more to the phenolic hydroxyl group for sufficient acetylation.

In the interfacial polymerization method, there can be mentioned a method in which an organic phase containing an acid chloride of isophthalic acid and an aqueous phase containing α-naphthol are brought into contact with each other to obtain di (α-naphthyl) isophthalate. The solvent used in the organic phase is a water-insoluble solvent that dissolves the acid chloride of isophthalic acid,
For example, toluene, hexane, dichloromethane and the like are preferable.

Further, in order to increase the purity of di (α-naphthyl) isophthalate synthesized by a known method including the above method, a method such as washing and reprecipitation is used. As impurities, the total amount of monomer components, monoesters, halogens, alkali metals or alkaline earth metals is 200 ppm or less, preferably 100 ppm or less.
ppm or less, more preferably 20 ppm or less. Since these impurities have the effect of increasing the dielectric loss tangent and the dielectric constant, it is important to reduce the content of these impurities as much as possible in order to produce an epoxy resin composition for low dielectric electronic materials.

Specifically, in the washing and precipitation steps, washing with sodium carbonate, caustic soda or the like in alkaline water or washing with deionized water is carried out, and a poor solvent for di (α-naphthyl) isophthalate such as heptane or methanol is used. Re-precipitation treatment, and then a washing treatment if necessary.

The compounding amount of di (α-naphthyl) isophthalate (B) in the epoxy resin composition for electronic materials of the present invention is such that the epoxy resin (A) has two or more epoxy groups in one molecule. Di (α-naphthyl) for equivalent
The ratio with the ester equivalent of isophthalate (B) is 0.3-
It is preferable that the di (α-naphthyl) isophthalate (B) is included in an amount of 1.5, more preferably 0.5 to 1.2, and even more preferably 0.8 to 1.1. It is preferable to include phthalate (B).

Di (α-naphthyl) isophthalate (B)
If the ratio of the ester equivalent to the epoxy equivalent of the epoxy resin (A) is less than 0.3, the epoxy resin is not completely cured, which is not preferable.
When it exceeds 1.5, it is difficult to obtain an epoxy resin cured product having sufficiently low dielectric properties, which is not preferable.

In the present invention, the curing accelerator (C) is used together with the epoxy resin curing agent di (α-naphthyl) isophthalate (B). Such curing accelerator (C)
As the above, a general curing accelerator for epoxy resin can be used.

Specific examples of the curing accelerator (C) include 2-
Imidazole compounds such as methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 2-undecylimidazole, triphenylphosphine,
Organic phosphine compounds such as tributylphosphine, trimethylphosphite, organic phosphite compounds such as triethylphosphite, phosphonium salts such as ethyltriphenylphosphonium bromide, tetraphenylphosphonium tetraphenylborate,

Trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine,
Amine compounds such as benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, 1,8 diazabicyclo (5,4,0) -undecene-7 (hereinafter abbreviated as DBU), DBU and terephthalic acid, Quaternary ammonium salts such as salts with 2,6-naphthalenedicarboxylic acid, tetraethylammonium chloride, tetrapropylammonium chloride, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrahexylammonium bromide, benzyltrimethylammonium chloride,

3-phenyl-1,1-dimethylurea, 3
-(4-Methylphenyl) -1,1-dimethylurea, chlorophenylurea, 3- (4-chlorophenyl) -1,
1-dimethylurea, 3- (3,4-dichlorophenyl)
Examples thereof include urea compounds such as -1,1-dimethylurea, alkalis such as sodium hydroxide and potassium hydroxide, and salts of crown ethers such as potassium phenoxide and potassium acetate. These are used alone or as a mixture of two or more kinds. be able to. Among these, the imidazole compound is preferably used.

The compounding amount of the curing accelerator (C) is 0.001 to 100 parts by weight of the epoxy resin (A).
It is 5.0 parts by weight. If it is less than 0.001 part by weight, the curing reaction will be slow, and if it exceeds 5.0 parts by weight, the storage stability will be lowered, and the self-polymerization of the epoxy resin will be a priority.

The method for obtaining a cured product using the epoxy resin composition of the present invention is not particularly limited, and known and commonly used methods can be mentioned. For example, a method of uniformly mixing the epoxy resin composition of the present invention, heating and melting, and molding to obtain a cured product, or dissolving the epoxy resin composition in a solvent to form a varnish, and then applying, pouring, or glass Impregnate the cloth substrate,
For example, the resin may be pre-cured and the solvent may be removed, and the resin may be heated and molded again.

More specifically, as a method for producing an epoxy resin laminate, an epoxy resin (A), di (α-naphthyl) isophthalate (B), and a curing accelerator (C) are used.
Prepare a varnish with solvent added to it, then impregnate it with glass cloth and dry at 160 ° C for 5 minutes to B stage (semi-cured)
To manufacture prepregs. A metal foil of gold, copper, aluminum or the like is attached to one or both sides of the prepreg, and 4 to 8 sheets are stacked,
There is a method of obtaining an epoxy resin substrate or a laminated plate by pressure molding for 1 hour at 170 ° C. and 3 MPa.

As the solvent for dissolving the epoxy resin composition of the present invention, various organic solvents capable of uniformly dissolving the epoxy resin, the active ester group-containing aromatic compound and the curing accelerator together are used.

The solvent used depends on the type of epoxy resin used and cannot be specified unconditionally, but in general, N
-Methylpyrrolidone, N-methylformaldehyde,
Amide solvents such as N, N'-dimethylformamide and N, N'-dimethylacetamide, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ether solvents such as tetrahydrofuran, 1,3-dioxolane and anisole , An aromatic hydrocarbon solvent such as toluene and xylene, and a monoether glycol solvent such as ethylene glycol monomethyl ether and ethylene glycol monobutyl ether.

These solvents may be used alone or as a mixture of two or more. Therefore, the solvent solubility of the epoxy resin curing agent is the production of sheets, laminates, resin-coated copper foil by coating and drying the resin composition, impregnation into cloth, non-woven fabric, etc., blending with other polymers, and fillers. Is extremely important for kneading in the solution state.

When the di (α-naphthyl) isophthalate of the present invention is used as a curing agent for an epoxy resin, the ester group of di (α-naphthyl) isophthalate reacts with the ring opening of the epoxy group, resulting in a less polar ester. A group is formed and a hydroxyl group is not formed. That is, the epoxy resin cured product has good water absorption properties, and also has a low dielectric property, that is, a low dielectric constant,
It has a low dielectric loss tangent. Further, di (α-naphthyl) isophthalate has high heat resistance because it contains only an aromatic ring and does not contain an alkylene chain, and as a wholly aromatic ester, it has a surprisingly high solubility in an organic solvent. Have,
The epoxy resin composition for electronic materials, which is easily mixed with an epoxy resin and further mixed with an epoxy resin, has excellent processability.

The epoxy resin composition for electronic materials of the present invention can obtain a cured product having a low dielectric constant, particularly a low dielectric loss tangent, as compared with the conventional epoxy resin. It can be effectively used for applications such as resins for resins, resins for sealants, and resins for various adhesives, and if necessary, substrates such as glass, aramid, polyester, and other cloths and nonwoven fabrics, or silica and mica. In a form containing a filler such as, it can be effectively used for applications such as a printed wiring board, a flexible printed wiring board, a fusion film for an interlayer insulating material for build-up, a coating material, and a copper foil with resin.

[0042]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these ranges.

First, a synthesis example of di (α-naphthyl) isophthalate (IAAN) is shown. <Synthesis Example 1> (Synthesis by acetic anhydride method) Isophthalic acid (manufactured by AJ International Chemical Co., Ltd.) was added to a 4-neck separable flask equipped with a stirring rod, a cooling tube, and a nitrogen introducing tube. 2 moles (33.23
g) and α-naphthol (manufactured by Sugai Chemical Co., Ltd.)
Add 4 mol (57.67 g) and acetic anhydride (manufactured by Wako Pure Chemical Industries, Ltd.) 0.48 mol (49.00 g), and add 3
Nitrogen was passed for 0 minutes to replace the inside of the system with nitrogen.

Then, the temperature was raised with stirring while flowing nitrogen, and the temperature was maintained at 145 ° C. for 3 hours to acetylate the hydroxyl group of α-naphthol. It was confirmed by 1H-NMR that the hydroxyl groups were almost acetylated. Furthermore, the temperature is raised to 2
When the temperature reached 30 ° C., the temperature was maintained for 1 hour, and then the temperature was gradually raised to 250 ° C. over 3 hours to carry out a deacetic acid reaction to carry out an esterification reaction.

Thereafter, the reaction product was taken out, pulverized and washed twice with boiling methanol to remove unreacted monomers and acetic acid. By vacuum drying at 60 ° C. for 10 hours, di (α-naphthyl) isophthalate (IAAN) 6 was obtained.
7.0 g was obtained. The obtained di (α-naphthyl) isophthalate (IAAN) was subjected to GPC measurement and the esterification rate was measured to be 97.4%.

<Synthesis Example 2> (Synthesis by interfacial polymerization method) In a 2 L separable flask equipped with a nitrogen introducing tube, 900 ml of distilled water and 0.5833 mol of sodium hydroxide (2
3.33 g) was added thereto, and nitrogen was sufficiently bubbled through the nitrogen introduction tube to remove oxygen in distilled water and the reaction system. There, 0.54 mol of α-naphthol (77.85
g) was allowed to dissolve for 1 hour. Then, it heated up to 60 degreeC. 600 ml of toluene was placed in another flask, and isophthalic acid chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) was used.
27 mol (54.82 g) were dissolved. The isophthalic acid chloride solution was heated to 60 ° C., and 1 was added to the α-naphthol solution which was stirred at 300 rpm with a Feddler blade.
The solution was dropped in 5 seconds and kept at the same rotation speed for 4 hours.

After the reaction was completed, the mixture was allowed to stand still and the aqueous phase was removed. The toluene phase was washed with 0.5% sodium carbonate water for 30 minutes and the stationary separation was repeated 3 times. Then, washing with deionized water for 30 minutes and standing liquid separation were repeated 3 times. afterwards,
After raising the temperature to remove about 400 ml of toluene and concentrating it,
600 ml of heptane was added dropwise over 15 seconds to precipitate di (α-naphthyl) isophthalate. Filter this, 3
Wash with 00 ml of methanol for 30 minutes at room temperature and filter-
106 g of di (α-naphthyl) isophthalate by drying
Got The esterification rate was 99.8%.

<Solubility of All-Aromatic Active Ester Group-Containing Compound in Various Solvents> Solubility of active ester in various solvents at 25 ° C. was evaluated, and the results are shown in Table 1.

[0049]

[Table 1]

The symbols in the table represent the following. IAAN: Di (α-naphthyl) isophthalate TAAN: Di (α-naphthyl) terephthalate IABN: Di (β-naphthyl) isophthalate TABN: Di (β-naphthyl) terephthalate 14NDAAN: 1,4-naphthalenedicarboxylic acid di (α) -Naphthyl) ester 26NDAAN: 2.6-naphthalenedicarboxylic acid di (α-naphthyl) ester TRAN: trimellitic acid tri (α-naphthyl) ester TMAN: trimesic acid tri (α-naphthyl) ester

<Examples 1 to 4 and Comparative Examples 1 to 4> Epoxy resins, active ester group-containing compounds, curing accelerators and solvents were mixed in the amounts shown in Table 2 to prepare varnishes. At this time, the active ester IAAN (di (α-
Naphthyl) isophthalate) was synthesized in Synthesis Example 2, and the measurement result of the impurity content was 20
ppm or less, Na ion 7ppm, Cl ion 11pp
It was m.

The prepared varnish was applied to an aluminum container, the solvent was removed at 50 ° C., and then B stage (semi-curing) was performed on a hot plate at 170 ° C. to further remove the solvent and pre-cure. . Then, it was peeled off from the aluminum container and powdered. 170 ℃ using this powder,
An epoxy resin cured product was obtained by pressure molding for 1 hour under the condition of 3 MPa. Further, it was cured at 190 ° C. under reduced pressure for 6 hours.

The glass transition temperature (Tg), dielectric properties, linear thermal expansion coefficient, solder heat resistance and copper foil peel strength of the epoxy resin cured products obtained in Examples 1 to 4 and Comparative Examples 1 to 4 were measured by the following methods. It was evaluated by.

(Glass transition temperature (Tg)) It was measured as a peak of tan δ at 1 Hz by DMS (DMS200 manufactured by Seiko Instruments Inc .: dynamic viscoelasticity measurement).

(Dielectric Property) The dielectric constant and dielectric loss tangent at 1 GHz were evaluated by an HP4291B RF impedance / material analyzer (manufactured by Agilent Technologies Co., Ltd.) according to JIS-C-6481.

(Linear coefficient of thermal expansion) TMA (TMA / SS120C manufactured by Seiko Instruments Inc .: thermomechanical analysis measurement)
Was evaluated from the expansion of the cured product in the range from around room temperature to around 50 ° C.

(Solder Heat Resistance) According to JIS-C-6481, the state of the test piece was visually evaluated by immersing it in a solder bath at 300 ° C. for 120 seconds. Swelling,
The case where there was no crack or the like was marked with ◯, and the case where blistering or cracking occurred was marked with x.

(Copper foil peel strength) JIS-C-6481
Autograph (Shimadzu Corporation, A
By GS-H), epoxy resin composition and copper foil (12μ
60 m thick, manufactured by Furukawa Circuit Foil Co., Ltd.
The evaluation was performed using a copper-clad laminate of × 40 × 2 mm. The evaluation results are shown in Tables 2 and 3.

[0059]

[Table 2]

[0060]

[Table 3]

The symbols in the table represent the following respectively. EPICLON HP-7200H: dicyclopentadiene type epoxy resin (Dainippon Ink and Chemicals, Inc.
Epoxy equivalent 280) Epicoat YX-4000: Biphenyl type epoxy resin (Yukaka Shell Epoxy Co., Ltd., epoxy equivalent 18
8) EPICLON N-660: Cresol novolac type epoxy resin (Dainippon Ink and Chemicals, Inc., epoxy equivalent 210)

EPICLON 152: Brominated epoxy resin (manufactured by Dainippon Ink and Chemicals, Inc., epoxy equivalent 363, bromine content = 48%) Phenolite TD-2090: Novolac type phenolic resin (manufactured by Dainippon Ink and Chemicals, Inc., OH equivalent 1
05) EPICLON B-650: Acid anhydride type epoxy resin curing agent (manufactured by Dainippon Ink and Chemicals, Inc., acid anhydride equivalent 168) 2E4MZ: 2-ethyl-4-methylimidazole Bu ₄ NBr: tetra-n-butyl. Ammonium bromide

Example 5 The varnish of Example 3 was applied to Fukuda Metal CF-T9 electrolytic copper foil (thickness of 12 μm), dried at 40 ° C. for 10 minutes, further dried at 120 ° C. for 10 minutes, and coated again. -Drying was repeated to suitably obtain a resin-coated copper foil having a thickness of 50 µm. 4 sheets of copper foil with resin at 170 ° C, 3M
A laminated plate was obtained by pressure molding at Pa. This was useful as a low dielectric buildup material.

From Tables 1 to 3, the adipic acid di (nitrophenyl) esters and sebacic acid di (thiophenyl) esters disclosed in Japanese Examined Patent Publication No. 4-8444 have excellent solvent solubility, but have an alkylene chain. Probably because of this, heat resistance is poor, and it is also difficult to obtain low dielectric properties such as a dielectric loss tangent of less than 1.0 × 10 ^{−2 at} 1 GHz and a dielectric constant of 3.2 or less, and di (thiobenzothiazyl) isophthalate. It is clear that the ester is wholly aromatic and has poor solvent solubility.

On the other hand, the curing agent di (α-naphthyl) of the present invention
Not only is isophthalate excellent in solvent solubility, an epoxy resin composition using di (α-naphthyl) isophthalate as a curing agent for an epoxy resin and a cured product obtained therefrom have excellent adhesiveness, solder resistance, and It is clear that it has curability and can achieve a low dielectric constant and dielectric loss tangent.

[0066]

INDUSTRIAL APPLICABILITY The present invention contains, as a curing agent, an active ester compound which has excellent heat resistance and low dielectric property, and also has excellent solvent solubility and is easily mixed with an epoxy resin. Epoxy resin composition for electronic materials that can be easily impregnated into equipment, and has excellent low dielectric properties, adhesiveness and heat resistance composed of its cured product, and is useful in a wide range of fields such as the electric / electronic industry and communication equipment industry. A low dielectric electronic material and, for example, a sheet and a laminate made of the low dielectric electronic material can be provided.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01B 3/40 H01B 3/40 CG 17/56 17/56 L // C08L 63:00 C08L 63:00 C (72) Inventor Katsuji Takahashi 5-21-2 Someino, Sakura City, Chiba Prefecture 4F071 AA42 AC10 AE02 AF05 AF40 AF45 AH12 AH13 BB02 BC01 BC02 4F100 AB17B AK53A BA02 BA07 GB43 JG05A JJ03 4J036 AA01 AC01 AD01 AD07 AD07 AD07 AD07 AF06 AJ08 DA02 DA04 DB23 DC02 DC25 DC41 DD07 JA08 5G305 AA06 AA14 AB10 AB24 AB36 BA09 BA18 CA15 CB08 CD08 CD12 5G333 AA03 AB12 AB21 CB12 CB19 DA04 DA11

Claims (9)

[Claims] 1. An epoxy for electronic materials, which comprises an epoxy resin (A) having two or more epoxy groups in one molecule, di (α-naphthyl) isophthalate (B) and a curing accelerator (C) as essential components. Resin composition. 2. Di (α-based on the epoxy equivalent of the epoxy resin (A) having two or more epoxy groups in one molecule.
It contains 0.3 to 1.5 of di (α-naphthyl) isophthalate (B) in a ratio with the ester equivalent of naphthyl) isophthalate (B), and is 0 based on 100 parts by weight of the epoxy resin (A). 0.001 to 5.0 parts by weight of a curing accelerator (C)
The epoxy resin composition for electronic materials according to claim 1, which comprises: 3. An epoxy resin (A) having two or more epoxy groups in one molecule is a cresol novolac type epoxy resin, a phenol novolac type epoxy resin, a naphthol modified novolac type epoxy resin, a bisphenol type epoxy resin, a biphenyl type epoxy resin. The epoxy equivalent selected from the group consisting of resin, triphenyl type epoxy resin, tetraphenyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, and brominated epoxy resin is 100 to 1000 (g / eq). The epoxy resin composition for electronic materials according to claim 1. 4. An epoxy for electronic materials, which comprises an epoxy resin (A) having two or more epoxy groups in one molecule, di (α-naphthyl) isophthalate (B) and a curing accelerator (C) as essential components. 1GH consisting of a cured product of a resin composition
A low dielectric electronic material having a dielectric loss tangent of less than 1.0 × 10 ^{−2 in} z. 5. The low dielectric electronic material according to claim 4, which has a dielectric constant of 3.2 or less at 1 GHz. 6. The residual phenolic hydroxyl group content is 20.
0 ppm or less, the total content of alkali metal, alkaline earth metal and free halogen is 250 ppm or less, and the dielectric loss tangent at 1 GHz is 4.0 × 10 ^−3.
The low dielectric electronic material according to claim 4, which is: 7. The low dielectric electronic material according to claim 6, which has a dielectric constant of 3.0 or less at 1 GHz. 8. A sheet made of the low dielectric electronic material according to claim 4. 9. A copper-clad laminate having a metal foil on one side or both sides of the sheet according to claim 8.