KR100314836B1 - Epoxy Resin Composition - Google Patents

Abstract

<Purpose> An epoxy resin composition which is used as a laminate of an electronic circuit board and exhibits excellent workability as well as a low dielectric constant and a low dielectric loss coefficient after curing is prepared. <Configuration> (A) Phenolic compound represented by the general formula (I) An epoxy resin composition containing at least one selected from the group consisting of a novolak resin prepared by condensation of formalin and (B) an epoxy resin prepared by glycidylating boric resin with epihalohydrin. In formula, R <1> is a C4-C12 alkyl group and n is an integer of 1-5.

Description

Epoxy resin composition

The present invention relates to an epoxy resin composition, and more particularly, to an epoxy resin composition exhibiting excellent workability after curing as well as a low dielectric dissipation factor.

Recently, as the application range of electric and electronic parts has been considerably widened, many battery electronic parts have been used in computers, automatic control, communication, business and game machines and equipment. In packing such electrical and electronic components, printed wiring boards are used to construct electrical or electronic circuits. The laminated body which laminated | stacked several sheets of prepreg in which the base material was impregnated with the epoxy resin at the time of such a printed wiring board structure is used.

There is a strong demand for such laminates to have lower dielectric constants for improved performance and miniaturization of electronic equipment. The finer the finer the circuit pattern, the faster the operation speed of the computer. However, such efforts face their physical limits and there is an increasing demand for reducing dielectric losses in insulating laminates to enable increased operating speeds.

Laminates used as circuit boards in phase communication should also have a lower dielectric loss factor to reduce transmission losses, and the laminate material should also have a lower dielectric constant to enable the manufacture of circuits of adequate size.

In such situations, several attempts have been made to use polyethylene resin and fluoroplastic as materials for producing laminates.

However, laminates prepared using polyethylene resins or fluoroplastics have the following defects.

(1) Because of poor moldability, it should be molded at high temperature

(2) Poor Dimensional Stability

(3) low adhesion with copper foil

Alternatively, the dielectric loss coefficient of the laminate can be reduced by using quartz material instead of the glass material used as the material. However, the resulting laminate has a great deal of wear on the drill, particularly during drilling.

In view of such a situation, an object of the present invention is to provide an epoxy resin composition which exhibits a low dielectric loss coefficient and a low dielectric constant after curing and is excellent in workability after curing.

According to this invention, the epoxy resin composition containing at least 1 chosen from the group which consists of the following is provided.

(A) A noblock resin prepared by condensing a phenolic compound represented by the following general formula (I) with formalin

(Wherein R ¹ is an alkyl group having 4 to 12 carbon atoms and n is an integer of 1 to 5)

(B) An epoxy resin prepared by glycidylating the knoblock resin with epihalohydrin.

The epoxy resin composition of the present invention contains at least one selected from (A) a knoblock resin and (B) an epoxy resin prepared by glycidylating the novolak resin.

Novolak resin (A) is produced by condensing formalin and a phenolic compound represented by the following general formula (I) in the presence of a catalyst.

In the general formula (I), R ¹ is an alkyl group having 1 to 12 carbon atoms, more preferably 6 to 9 carbon atoms, and n is an integer of 1 to 5. Phenolic compounds include, for example, alkylphenols such as p-octylphenol, p-nonylphenol, p-hexylphenol, and p-pentylphenol. Among them, it is preferable that the carbon atom closest to the benzene nucleus is quaternary carbon in order to provide a final cured composition having a low dielectric constant and a high dielectric transition temperature. Phenolic compounds can be used individually or in combination of 2 or more.

Paraformaldehyde may also be used in place of formalin.

In order to provide a composition of the present invention having improved heat resistance after curing, the phenol compound represented by the general formula (I) and formalin are 0.2 to 1.05 as molar ratio of formalin / phenol compound; More preferably, it is good to use from 0.5 to 0.9.

Examples of catalysts used for condensation of phenolic compounds with formalin include acids such as sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid and p-toluenesulfonic acid. Among them, p-toluenesulfonic acid, which is strongly acidic and has good compatibility with reagents, is the best. The catalyst is usually used in an amount of 0.5 to 5 mol%.

Novolak resin (A) used in the present invention has an improved heat resistance after curing and a suitable melt viscosity and thereby has a good fluidity during processing to provide a final composition excellent in impregnating glass cloth during the manufacture of laminates It is good to have a number average molecular weight of -1800, more preferably 600-1600.

The epoxy resin component (B) used for this invention can also be manufactured by glycidylating the novolak resin (A) mentioned above with epihalohydrin.

Among the novolak resins (A) as described above, those used in the production of the epoxy resin (B) have improved heat resistance and a suitable melt viscosity after curing, thereby having a good fluidity during processing, and thus advantageous in the manufacture of the laminate. It is preferable to have a number average molecular weight of 400 to 1600, most preferably 600 to 1400, which can provide a final composition having excellent cloth impregnation.

Representative epihalohydrins used for glycidylation of the novolak resin (A) include epichlorohydrin and β-methyl epichlorohydrin.

In the production of the epoxy resin (B) of the present invention, the reaction of the novolak resin (A) and epihalohydrin can be carried out by various conventionally known methods. For example, (a) etherification and dehydrohalogenation are performed simultaneously, (b) etherification and dehydrohalogenation are performed sequentially, and etherification and dehydrohalogenation are sequentially performed in terms of stable quality of the final epoxy resin. Method (b) is advantageous.

In the method (a) in which etherification and dehydrohalogenation are carried out simultaneously, the novolak resin (A) and epihalohydrin are subjected to 60 to 90 in the presence of an alkali compound and in the presence of water so as to simultaneously carry out the etherification and the dehydrohalogenation. The reaction is carried out at a temperature of ℃. Then, unreacted halohydrin, water and by-product salts are removed from the reaction mixture, and the residue is dried to obtain an epoxy resin (B).

Alkali compounds that can be used include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide, of which sodium hydroxide is the best.

In the method (a), the alkali compound is used in an amount of at least 1 mole, more preferably 1.02 to 1.05 mole per 1 equivalent of phenol hydroxyl group in the novolak resin (A).

In method (b) in which etherification and dehydrohalogenation are performed sequentially, etherification is carried out, for example, tertiary amines such as tertiary amines such as trimethylamine and triethylamine, triphenylphosphine, tributylphosphine, and the like. Quaternary ammonium salts such as tetramethylammonium chloride, tetramethylammonium bromide, tetraethylammonium chloride, tetraethylammonium bromide, chlorine chloride, tetramethylphosphonium bromide, tetramethylphosphonium iodide, triphenylpropylphosphonium bromide It can be carried out in the presence of an etherification catalyst selected from tertiary sulfonium salts such as quaternary phosphonium salts, benzyldibutylsulfonium chloride, benzyldimethylsulfonium chloride, and the like. Of these, the fourth abmonium salt is the best.

Such etherification catalyst is used in an amount of 0.005 to 5 mol% per equivalent of phenol hydroxyl group in the novolak resin (A).

In the etherification step, the reaction is continued until at least 30%, preferably at least 50%, more preferably at least 80% of the hydroxyl groups in the novolak resin (A) are etherified. The etherification reaction is usually carried out at a temperature of 60 ° C to 110 ° C for 1 to 12 hours in the absence of water. If water is present in the reaction system, it is better to adjust the water content to 3.0% by weight or less.

The reaction product of the etherification step comprising unreacted epihalohydrin is used as such in the dehydrohalogenation step. Dehydrohalogenation is carried out in the presence of a catalyst which is an alkali compound used in the etherification step described above, for example alkali metal hydroxide, preferably sodium hydroxide.

In the dehydrohalogenation step, the alkali compound is used in an amount of at least 0.5 mole, more preferably 0.8 mole per one equivalent of phenol hydroxyl group in the novolak resin (A).

In order to prevent inconvenience such as gelation of the reaction product, it is preferable to use an alkali compound of 1 mole or less per equivalent of phenol hydroxyl group.

Dehydrohalogenation is normally performed at a temperature of 60-100 degreeC for 1-3 hours. When using sodium hydroxide as a catalyst, it is preferable to carry out the reaction while removing byproduct water from the reaction system. Such water removal can be carried out, for example, using azeotropes between water and epihalohydrin under reduced pressure. In such cases epihalohydrin may circulate into the reaction system.

After completion of the reaction, the unreacted epihalohydrin is removed from the reaction product by distillation under reduced pressure, and then the reaction product is washed with water to remove the byproduct salt. If necessary, the reaction product can be neutralized with lead acid and a weak acid such as sodium phosphate dihydrate. Then, the reaction product may be dried to obtain an epoxy resin (B).

The epoxy equivalent of the epoxy resin (B) thus produced is 800 g / eg or less, preferably 600 g / eq or less, more preferably 400 g / eq or less in terms of obtaining a composition having good impregnation properties in the manufacture of the laminate. .

The composition of the present invention includes at least one selected from the group consisting of the above-described novolak resin (A) and epoxy resin (B). In other words, the composition of the present invention may contain only the novolak resin (A) as the main component or only the epoxy resin (B) or both the novolak resin (A) and the resin (B) component as the main component. If the composition of the present invention comprises the quantum of novolak resin (A) and epoxy resin (8), the final composition shows a greatly reduced dielectric constant after curing. In this case, the composition contains a novolak resin (A) and an epoxy resin (B) such that the ratio (R) represented by the following formula (1) is 0.9 to 1.05, preferably 0.95 to 1.0. :

The composition of the present invention may also contain other epoxy compounds in a range that does not adversely affect the advantageous features of the composition. Examples of such other epoxy compounds include bisphenol A epoxy resin, bisphenol F epoxy resin, 1,1-bis (glycidoxyphenyl) ethane, phenol novolak epoxy compound, 0-cresol novolak epoxy compound, glycidyl ester epoxy compound , Glycidyl amine epoxy compounds, alicyclic epoxy compounds and trisphenol epoxy compounds. Examples of trisphenol epoxy compounds include 1- [α-methyl-α- (4'-hydroxyphenyl) ethyl] -4- [α'-α'-bis (4'-hydroxyphenyl) ethyl] benzene. Epoxy compounds and epoxy compounds of 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane.

Diglycidyl ether of tetrabromobisphenol A may be added to cure the composition of the present invention to obtain a cured product having flame retardancy.

The composition of this invention may also contain various arbitrary components other than the component mentioned above. Examples of such optional components include non-reactive diluents such as phthalates, glycol ethers, glycol esters and phenols, and long chain alkene oxides, butylglycidyl ethers, phenylglycidyl ethers and P-butylphenylglycidyl ethers. Reactive diluents, modified polybutadiene and modified carboxyl-terminated butadiene acrylonitrile copolymers, calcium carbonate, clay, asbestos, silica, mica, powdered quartz, powdered aluminum, graphite, titanium oxide, alumina, iron oxide, powder glass, glass Fillers such as fibers, and colorants such as carbon block, toluidine red, Hansa yellow, phthalocyanine blue and phthalocyanine green.

The epoxy resin composition of the present invention can be prepared by a method of melting the above-mentioned components by melting or mixing in a suitable solvent.

Heat melting may be performed at a temperature of about 20 to 50 ° C. above the melting point of the components.

Examples of solvents that can be used include toluene, xylene, methylethylketone, dioxane and methylcellosolve.

In order to cure the composition of the present invention, a mixture of the novolak resin (A) and / or the epoxy resin (B) and the components optionally added are mixed with a curing agent and a curing accelerator as necessary for 120 to 180 hours for 1 to 8 hours. Heat at a temperature of ° C.

The curing agent that can be used in combination with the epoxy resin composition of the present invention is not limited to a specific type. Representative curing agents include, for example, polyfunctional phenolic compounds, acid anhydrides, aromatic polyamines, aliphatic polyamines and imidazoles.

Examples of polyfunctional phenolic compounds include phenolic novolak, O-cresol novolak, 1- [α-methyl-α- (4'-hydroxyphenyl) ethyl] -4- [α'-α'-bis (4 '-Hydroxyphenyl) ethyl] -benzene and 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane.

Examples of acid anhydrides include phthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnaphthalenedicarboxylic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenonetetracarboxylic anhydride and dodecyl stone. Carboxylic acid anhydride and chloronorbornene dicarboxylic acid anhydride.

Examples of aromatic polyamines include diaminodiphenylmethane and diaminodiphenyl sulfone.

Examples of aliphatic polyamines include triethylenetetramine, diethylenetriamine, mantendiamine, N-aminoethylpiperidine, isophoronediamine and 3,9-bis (3-aminopropyl) -2,4,8,10- Detraspiro [5,5] undecane.

Examples of imidazoles include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, ethyl-4-methylimidazole and 1- Benzyl-2-methylimidazole and the like.

In the present invention, curing agents such as dicyandiamide and m-xylenediamine may also be used.

In the present invention, the above-mentioned curing agents may be used alone or in combination of two or more.

Examples of curing accelerators include imidazoles and tertiary amines as described above.

Examples of tertiary amines include N, N-benzyldimethylamine and 2,4,6-tris (dimethylaminomethyl) phenol.

Other curing accelerators include, for example, 1,8-diazabicyclo- [5,4,0] -undecene-7 octylidee, a complex of monoethylamine and trifluorouroborane, 1-benzyl-2-methylimidazole , 2-ethyl-4-methylimidazole, and the brand name Vcat SA102 made by Sun Abbott.

In the present invention, curing accelerators may be used alone or in combination of two or more.

At the time of curing the composition of the present invention, the amount of the curing agent can be used in an amount such that the ratio of the epoxy equivalent of the epoxy resin (B) and the active hydrogen equivalent of the curing agent is 0.4 to 1.20, preferably 0.8 to 1.05. When the curing agent used is an acid anhydride, an amount within which the ratio of the epoxy equivalent of the epoxy resin (B) to the molar amount of the acid anhydride is within the above-mentioned range is used. When using a hardening accelerator, 0.1-3 weight part is used per 100 weight part of epoxy resins (B) normally.

The composition of the present invention can be suitably used for copper clad laminates, laminates of low dielectric constant, ceramics of low dielectric constant, and the like. In preparing the copper clad laminate, the composition of the present invention is first dissolved in a solvent to produce a varnish, and then a matrix of glass cloth, glass fiber nonwoven fabric, synthetic fiber or paper is impregnated or coated with the varnish. The prepreg is prepared by removing the solvent by heating the impregnated or coated matrix with a heat gun, and then stacking the prepreg several sheets to prepare a laminate. Then, copper foil is coated on one side or both sides of the laminate, and then heated and pressurized to cure the composition of the present invention to produce a copper clad laminate.

The invention is explained in more detail with reference to the following examples and comparative examples.

Example

In heat transfer examples, the glass transition temperature, dielectric constant, dielectric loss coefficient, copper peeling strength, solder resistance and flame resistance were measured according to the following method.

Glass transition temperature, Tg

It measured with the differential scanning calorimeter as follows under the following measurement conditions.

Differential Scanning Calorimeter:

Seiko 1 DSC100

SEIKO 1 DSC 5040 (disk station)

Measuring conditions :

Temperature range: 25 ~ 200 ℃

Temperature rise rate: 10 ℃ / min

Sampling time: 0.5 second

Sampling amount: 10mg

Dielectric constant and dielectric loss factor

The dielectric loss measuring apparatus (Ando Electric Corp. Model TR-10C) was measured according to JIS K6911.

Copper peeling strength

Prepreg was prepared by impregnating a 100 μm thick glass cloth (WEA116E105F manufactured by Nito Bonded Co., Ltd.) with an epoxy resin composition, stacking 5 sheets of prepregs, and placing 35 μm thick copper foil (3EC-3, manufactured by Mitsui Metal Co., Ltd.) on one surface thereof. A copper clad laminate was prepared by pressing at a temperature of 170 ° C. and a pressure of 40 kgf / cm 2 for 60 minutes after the batch. In order to evaluate the peel strength of the copper coating, the sample was cut from the laminate manufactured according to JIS C6481, and then one end of the copper coating (thickness, 37 μm) previously peeled to the bite device of the tensile tester and the copper coating was removed under normal conditions. Copper peeling strength (kgf / cm (N / cm)) was measured at peel strength of 90 ° C. according to JIS C6481.

Solder Resistant

Soldering resistance was evaluated in accordance with JIS S6481. A sample was prepared by removing the entire copper coating on one surface of the copper clad laminate and removing the copper coating half on the opposite surface. Samples were treated under conditions of C-3 / 121/100 (in air having a temperature of 121 ° C. and a relative humidity of 100%) and then immersed in a solder bath at 260 ° C. to assess the presence of bubbles.

Flameproof

Flame resistance was evaluated by a vertical flame tester according to UL94.

Example 1

A reactor equipped with a reflux condenser, a stirrer and a thermometer was charged with 909.3 g of P-octylphenol and 8.4 g of p-toluenesulfonic acid monohydrate, and the reactor was replaced with nitrogen and then heated to 95 ° C. Subsequently, the reactor was replaced with nitrogen while maintaining the temperature at a reflux temperature of 98-99 ° C., while 303.7 g of 37% formalin was added to the mixture from the dropping funnel at a constant rate for 2 hours, and then refluxed again for 15 minutes. The reflux condenser was replaced by a distillation apparatus.

The temperature was gradually increased to 130 ° C., the methanol and water were evaporated off, and then the temperature was continuously increased. The reactor was slowly pressurized under nitrogen atmosphere and finally maintained at 150 ° C. and 15 mm Hg for 30 minutes to distill off the low boiling point compound.

After the pressure in the reactor was restored to normal pressure, 800 ml of toluene was added to the reaction mixture to form a uniform toluene solution, neutralized with 1 L of 10% aqueous sodium hydrogen carbonate solution, washed with toluene solution with 500 ml of water, and then at 150 ° C. After the azeotropic dehydration, the filtrate filtered with a glass filter (G4) was heated in an oil bath at 150 ° C. under a reduced pressure of 15 mmHg to remove toluene, and then heated under a reduced pressure of 5 mmHg or less for 2 hours in an oil bath at 220 ° C. to remove unreacted monomers. 914 g of novolak resin was prepared by removing.

The number-average molecular weight (Mn) and weight-average molecular weight (Mw) of the novolak resin thus obtained were measured as 1.162 and 1,174, respectively, and the hydroxyl equivalent was 219g / eq and the softening point was 110 ℃.

Example 2

The procedure of Example 1 was repeated except that the amounts of P-octylphenol, P-toluenesulfonic acid monohydrate and 37% formalin were used at 5000 g, 46.0 g, and 1.279 g, respectively, to prepare 4,815 g of novolak resin.

The number average molecular weight (Mn) of the obtained novolak resin was 1,048, the weight average molecular weight (Mw) was 1,240, the hydroxyl equivalent was 220 g / eq, and the softening point was 86 degreeC.

Example 3

The procedure of Example 1 was repeated except that the amounts of P-octylphenol, P-toluenesulfonic acid monohydrate and 37% formalin were used at 1,160 g, 384.6 g, and 1.0 g, respectively, to prepare 1,158 g of novolak resin.

The number average molecular weight (Mn) of the obtained novolak resin was 935, the weight average molecular weight (Mw) was 1603, the hydroxyl equivalent was 235 g / eq, and the softening point was 59 degreeC.

Example 4

438 g of the novolak resin prepared in Example 1, 920 g of epichlorohydrin, 0.88 g of a 50% aqueous tetramethylammonium chloride solution and 26.8 g of water were added to a 2 L reactor equipped with a thermometer and reacted at 90 DEG C for 4 hours with stirring. . The temperature was then lowered to 70 ° C. and 162.5 g of 48% aqueous sodium hydroxide solution were added over 2 hours. In the meantime, the water was removed using the azeotropy of epichlorohydrin and water under reduced pressure so that the concentration of water in the reactor was constant at about 2%, leaving epichlorohydrin in the reaction mixture. After the addition of the aqueous sodium hydroxide solution, the reaction was further stirred for 30 minutes. After completion of the reaction, the remaining epichlorohydrin was removed under reduced pressure while gradually raising the temperature to 120 ° C. Then, 550 g of toluene and 370 g of warm water were added, followed by stirring for 30 minutes under reflux to remove the toluene phase. The toluene phase thus obtained was azeotropically dehydrated and filtered through a celite-coated glass filter (G4) to filter insolubles to obtain a reaction product dissolved in toluene. The toluene solution was removed at the temperature of 150 degreeC under reduced pressure, and 350g of epoxy resins were obtained.

It was 522g / eq when the epoxy equivalent of the epoxy resin thus obtained was measured. The amount of hydrolyzable chlorine of the epoxy resin was 0.007% by weight, and the softening point was 101 ° C.

Example 5

400 g of the novolak resin prepared in Example 1, 1837 g of epichlorohydrin, 4.0 g of 50% aqueous tetramethylammonium chloride solution and 22.7 g of water were added to a 2 L reactor equipped with a thermometer, and reacted at 90 ° C. for 5 hours while stirring. . The temperature was then lowered to 70 ° C. and then 142 g of 48% aqueous sodium hydroxide solution was added over 2 hours. In the meantime, the water was removed using the azeotropy of epichlorohydrin and water under reduced pressure so that the concentration of water in the reactor was constant at about 2%, leaving epichlorohydrin in the reaction mixture. After the addition of the aqueous sodium hydroxide solution, the reaction was further stirred for 30 minutes. After completion of the reaction, the remaining epichlorohydrin was removed under reduced pressure while gradually raising the temperature to 120 ° C, 500 g of xylene and 320 g of hot water were added, followed by stirring for 30 minutes under reflux to extract the xylene phase. The xylene phase thus obtained was azeotropically dehydrated and filtered through a celite-coated glass filter (G4) to filter insoluble materials to obtain a reaction product dissolved in xylene. The xylene solution was removed at a temperature of 150 ° C. under reduced pressure to obtain 470 g of epoxy resin.

It was 378 g / eq when the epoxy equivalent of the epoxy resin thus obtained was measured. The amount of hydrolyzable chlorine of the epoxy resin was 0.007% by weight, and the softening point was 78 ° C.

Example 6

400 g of the novolak resin prepared in Example 1, 1837 g of epichlorohydrin, 8.0 g of a 50% aqueous tetramethylammonium chloride solution and 21.0 g of water were added to a 2 L reactor equipped with a thermometer and reacted at 90 ° C. for 4 hours while stirring. . The temperature was then lowered to 70 ° C. and then 127 g of 48% aqueous sodium hydroxide solution was added over 2 hours. In the meantime, the water was removed using the azeotropy of epichlorohydrin and water under reduced pressure so that the concentration of water in the reactor was constant at about 2%, leaving epichlorohydrin in the reaction mixture. After the addition of the aqueous sodium hydroxide solution, the reaction was further stirred for 30 minutes. After the reaction was completed, the remaining epichlorohydrin was removed under reduced pressure while gradually raising the temperature to 120 ° C, 500 g of xylene and 290 g of warm water were added, followed by stirring for 30 minutes under reflux to extract the xylene phase. The xylene phase thus obtained was azeotropically dehydrated and filtered through a celite-coated glass filter (G4) to filter insoluble materials to obtain a reaction product dissolved in xylene. The xylene solution was removed at a temperature of 150 ° C. under reduced pressure to obtain 480 g of epoxy resin.

It was 377 g / eq when the epoxy equivalent of the obtained epoxy resin was measured. The amount of hydrolyzable chlorine of the epoxy resin was 0.009% by weight, and the softening point was 55 ° C.

Example 7

22.9 g of the novolak resin obtained in Example 1 and 59 g of the epoxy resin obtained in Example 4 were placed in a detachable flask, melted and degassed at 180 ° C., and 0.12 g of 2-methylimidazole was added to the mixture to add an epoxy resin composition. Prepared. The epoxy resin composition thus obtained was placed in a rectangular mold of 2 mm (thickness) x 15 cm (length) x 15 cm (width) and then cooled after compression molding at 170 ° C for 8 hours. The cured molded plate thus obtained was taken out of the mold and the measured Tg was 136 占 폚, the dielectric constant (1 MHZ) was 2.60, and the dielectric loss factor (1 MHZ) was 0.009.

Example 8

The plate of the cured epoxy resin composition was prepared by repeating the procedure of Example 7 except that 24.5 g of the novolak resin obtained in Example 3 was used instead of the novolak resin of Example 1, and the evaluation result Tg was 118 DEG C, dielectric constant. The constant (1 MHZ) was 2.65 and the dielectric loss factor (1 MHZ) was 0.009.

Example 9

104 g of the novolak resin obtained in Example 1 and 216 g of the novolak epoxy resin obtained in Example 4 were added to a 1 L detachable flask, and the mixture was heated to 150 ° C. while stirring to add 222 g of methylethylkenone.

The solution so obtained had 65% solids. The solution was then cooled to room temperature and 3.0 g of 2-ethyl-4-methylimidazole was added to prepare a varnish. The gelation time of the varnish thus obtained was 13 minutes 30 seconds at 140 ° C.

The obtained varnish was impregnated into a glass cloth (WEA18W105F115N manufactured by Nito Bonded Co., Ltd.) and then dried at 140 ° C. for 10 minutes to prepare a prepreg. Nine prepregs were compression molded at 170 ° C. for 3 hours to prepare a 1.74 mm thick laminate having a resin content of 35%.

Tg (DSC) of the laminate was 135 deg. C, dielectric constant (1 MHZ) was 3.92, and dielectric loss coefficient (1 MHZ) was 0.007.

Example 10

A diglycidylated tetrabromobisphenol A of 35.1 g of the novolak resin obtained in Example 1 and 25.1 g of the novolak epoxy resin obtained in Example 4, 396 g / eq of epoxy equivalent and bromine content of 48.1% in a 1 L detachable flask 39.5 g were added and heated to 150 ° C. while stirring to melt the mixture, followed by 45 g of methylethylkenone. The solution so obtained had 65% solids. The solution was then cooled to room temperature and 0.8 g of 2-ethyl-4-methylimidazole was added to prepare a varnish. The gelation time of the varnish thus obtained was 9 minutes 43 seconds at 150 ° C.

The obtained varnish was impregnated into a glass cloth (WEA18W105F115N manufactured by Nito Bonded Co., Ltd.) and then dried at 150 ° C. for 5 minutes to prepare a prepreg. Ten prepregs were compression molded at 170 ° C. for 3 hours to prepare a 1.1 mm thick laminate having a 46% resin content.

The laminate had a Tg (DSC) of 144 占 폚, a dielectric constant of 1 MHZ of 3.8 and a dielectric loss factor of 1MHZ of 0.008. Copper peeling strength was 1.0kgf / cm and C-3 / 121/100 was clean without soldering air bubbles. Flame retardant according to the criteria of UL-94 was V-0.

Example 11

Diglycidylated tetrabrobobisphenyl having 27.4 g of the novolak resin obtained in Example 2 and 18.1 g of the novolak epoxy resin obtained in Example 6, 395 g of epoxy equivalent and 48.1% bro content in a 1 L detachable flask 39.5 g of A and 1- [α-methyl-α (4'-hydroxyphenyl) ethyl] -4- [α'-α'-bis (4'-hydroxyphenyl) ethyl] benzene were added and stirred at 150 ° C. After heating to melt the mixture, 45 g of methylethylkenone was added. The solution so obtained had 65% solids. The solution was then cooled to room temperature and 0.8 g of 2-ethyl-4-methylimidazole was added to prepare a varnish. The gelation time of the varnish thus obtained was 9 minutes 15 seconds at 150 ° C.

The obtained varnish was impregnated into a glass cloth (WEA18W105F115N manufactured by Nito Bonded Co., Ltd.) and then dried at 150 ° C. for 5 minutes to prepare a prepreg. Nine prepregs were compression molded at 170 ° C. for 3 hours to prepare a 1.0 mm thick laminate having a 47% resin content.

The laminate had a Tg (DSC) of 138 占 폚, a dielectric constant of 1 MHZ of 3.9 and a dielectric loss factor of 1MHZ of 0.008. Copper peeling strength was 1.4kgf / cm, C-3 / 121/100, and soldering resistance was clean without bubble. The conventional flame retardancy of UL-94 was V-0.

Example 12

In a reactor equipped with a stirrer, a reflux cooler, a drop channel and a thermometer, 393.8 g of 1,1-bis (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,221 g of epichlorohydrin and 33 g of water were added. The mixture was heated to 70 ° C, and 1.2 g of 1,1-bis (2-methyl-4-hydroxy-5-tert-butylphenyl) butane was melted and 1.2 g of an aqueous solution of tetramethylammonium chloride having a concentration of 53.2% by weight was added. Stir at 70 ° C. for 2 hours and then add 48wt% and 169.6 g of sodium hydroxide aqueous solution under reduced pressure for 2 hours, while maintaining the temperature at 70 ° C. and using water azeotropy between 36.6 g and epichlorohydrin. Removed. In the reaction system having water, epichlorohydrin was separated from the water and recovered into the reaction system, and then the pressure of the reaction system was adjusted to remove the sum of the water generated in the reaction per unit time and the water in the added aqueous sodium hydroxide solution and the reaction system per unit time. Make sure the amount of water is the same.

After the addition of the aqueous sodium hydroxide solution, the mixture was stirred at 70 ° C. for another 30 minutes, the remaining epichlorohydrin and water were removed under reduced pressure, and 634.6 g of methyl isobutyl ketone and 377 g of water were added thereto, followed by stirring at 95 ° C. for 1 hour 30 minutes. It was then left to separate into an organic phase and an aqueous phase. The sample was purified from the organic phase and then the solvent was removed therefrom. As a result, the hydrolyzable chlorine content was 0.58% by weight.

Then, the organic phase was placed in a reactor, heated to 90 ° C., and then 9.8 g of an aqueous 48 wt% sodium hydroxide solution corresponding to 1.5 times the molar amount of the hydrolyzable chlorine content described above was added thereto, stirred at 90 ° C. for 2 hours, and then 30 wt% phosphoric acid 1 After neutralizing with 70.4 g of aqueous sodium solution, the mixture was left to separate into an organic phase and an aqueous phase. The separated organic phase was azeotropically extracted to remove water and then filtered through a glass filter to remove inorganic salts. The filtrate was distilled off under reduced pressure to remove methyl isobutyl ketone to obtain 485 g of a glassy epoxy resin. The epoxy resin obtained had an epoxy equivalent of 284 g / eq and a hydrolyzable chlorine content of 0.015 wt%.

Example 13

970 g of the epoxy resin obtained in Example 12, 500 g of tetrabromobisphenol, and 160 g of xylene were added to a 2-liter detachable flask, and 2.2 ml of 10% aqueous tetramethylammonium chloride solution was added, and the flask was cleaned with nitrogen, followed by mixture. When the reaction mixture was heated to 100 ° C., the pressure of the reaction system was decreased, and then heated to 150 ° C. to remove xylene and water from the reaction system. Then, after returning to normal pressure, the mixture was stirred at 50 ° C. for 8 hours to prepare 1470 g of epoxy resin. Manufactured.

The epoxy equivalent of epoxy resin was 957 g / eq, the softening point was 125 degreeC, and the bromine content was 20 weight%.

Example 14

A varnish was prepared by dissolving 100 g of the epoxy resin obtained in Example 13, 27.3 g of the novolak resin obtained in Example 1, and 1.0 g of 2-ethyl-4-methylimidazole in 50 g of methyl ethyl ketone. A prepreg was prepared by impregnating a glass cloth (6232/1050 / AS50 manufactured by Asahi Shueberessa) with a varnish and then drying at 170 ° C. for 5 minutes.

Nine prepregs were stacked and pressed for 30 minutes at 180 ° C., followed by heat curing at 190 ° C. for 15 hours to prepare a 1.3 mm thick laminate having a resin content of 39.5 g weight%.

The laminate had a Tg of 144 占 폚, a dielectric constant of 1 MHZ of 3.5 and a dielectric loss coefficient of 1 MHZ of 0.0066.

Example 15

30.0 g of the epoxy resin obtained in Example 4, 9.7 g of anhydrous methylhexahydrophthalic acid (Liquacid MH700 manufactured by Shin-Nihon Corporation) and 0.15 g of a curing accelerator (U-cat 102SA manufactured by Sunaprosa) were added to a detachable flask to 120 ° C. After degassing, the molten mixture is degassed in a rectangular mold of 2 mm (thickness) × 15 cm (length) × 15 cm (width), then heated to 120 ° C. for 2 hours, 150 ° C. for 2 hours, and 170 ° C. for 4 hours. The cured epoxy resin composition plate obtained by curing was cooled and then removed from the mold.

The cured epoxy resin composition had a Tg of 160 ° C., a dielectric constant of 1.90 (1 MHZ), and a dielectric loss factor (1 MHZ) of 0.010.

As described above, the epoxy resin composition of the present invention exhibited a low dielectric constant and a low dielectric loss coefficient after curing, and also showed high workability after curing.

Therefore, it is well suited for producing copper clad laminates, laminates of low dielectric constants and ceramic materials of non-dielectric constants.

Claims (6)

(A) a novolak resin produced by condensing a phenol compound represented by the following general formula (I) with formalin; Wherein R ¹ is an alkyl group having 4 to 12 carbon atoms, n is an integer of 1 to 2, (B) The epoxy resin composition containing the epoxy resin produced by glycidylating the said novolak resin with epihalohydrin so that ratio (R) represented by following formula (1) may be 0.9-0.05. The epoxy resin composition according to claim 1, wherein the novolak resin (A) is a novolak resin prepared by condensing the formalin and the phenol compound at a formalin / phenol compound molar ratio of 0.2 to 1.05. The epoxy resin composition according to claim 1, wherein the novolak resin (A) is a novolak resin prepared by condensing the formalin and the phenolic compound in the presence of P-toluenesulfonic acid as a catalyst. The epoxy resin composition according to claim 1, wherein the novolak resin (A) has a number average molecular weight of 400 to 1800. The epoxy resin composition according to claim 1, wherein the novolak resin (A) used when the epoxy resin (B) is prepared by glycidylating with epihalohydrin has a number average molecular weight of 400 to 1600. The epoxy resin composition according to claim 1, wherein an epoxy equivalent of the epoxy resin (B) is 800 g / eq or less.