JP2949771B2 - Epoxy resin composition - Google Patents

Description

The present invention relates to an epoxy resin composition.

[Conventional technology]

As a novolak type epoxy resin obtained by reacting a cresol novolak resin with epichlorohydrin, a 3% (weight / volume) dichloromethane solution in JP-A-59-184250 was measured using an infrared spectrophotometer at a cell length of 2 mm. The maximum value of the absorbance at a wave number of 3500 to 3600 cm ^-1 is 0.
Less than 15 are known.

[Problems to be solved by the invention]

However, the cured product of the epoxy resin composition described in JP-A-59-184250 is still insufficient in heat resistance.

[Means for solving the problem]

The present inventors have intensively studied to obtain an epoxy resin composition that gives a cured product having more excellent heat resistance in view of the above circumstances, the maximum value of absorbance at a specific wave number is 0.15 or less, and the epoxy equivalent is a raw material. The substituted phenol novolak resin having a hydroxyl equivalent of not more than 75 gave a cured product having extremely excellent heat resistance, and it was found that it was also excellent in crack resistance and water resistance, and completed the present invention.

That is, the present invention relates to a substituted phenol novolak type epoxy resin, and the maximum value of the absorbance at a wave number of 3500 to 3600 cm ⁻¹ measured with a 3 mm (w / v) dichloromethane solution at a cell length of 2 mm using an infrared spectrophotometer. Is an epoxy resin composition containing the epoxy resin having an epoxy equivalent of 0.15 or less and an epoxy equivalent of a hydroxyl equivalent of a substituted phenol novolak resin used as a raw material plus 75 or less.

The substituted phenol novolak type epoxy resin according to the present invention refers to an epoxidized product of a substituted phenol novolak resin.

The novolak type epoxy resin in the present invention can be prepared, for example, by reacting a novolak resin of a substituted phenol with epichlorohydrin in the presence of an alkali such as caustic soda.

The novolak resin of substituted phenols can be obtained, for example, by subjecting a substituted phenol described below and formaldehyde to a condensation reaction in the presence of an acid or alkali catalyst by a known method.

A substituted phenol used in the production of a novolak resin of a substituted phenol refers to one in which a hydrogen atom on the aromatic ring of the phenol is substituted with any substituent. Examples of the substituted phenol include an alkyl group and an alkenyl group. ,
Phenols substituted with an allyl group, an aryl group, an aralkyl group or a halogen atom, specifically cresol,
Xylenol, ethyl phenol, isopropyl phenol, butyl phenol, octyl phenol, nonyl phenol, vinyl phenol, isopropenyl phenol, allyl phenol, phenyl phenol, benzyl phenol, chloro phenol, bromo phenol (including o, m, p-isomers respectively), etc. No. Of these, cresol, particularly ortho-cresol, is preferably used.

As the novolak resin of the substituted phenols, those having various hydroxyl equivalents can be used, and as the orthocresol novolak resin, those having a hydroxyl equivalent of 118 to 122, among which 118 to 120 are preferable.

The substituted phenol novolak type epoxy resin according to the present invention has a wave number of 3500 measured with a 3 mm (w / v) dichloromethane solution at a cell length of 2 mm using an infrared spectrophotometer.
The maximum value of the absorbance at ~ 3600 cm ^-1 is 0.15 or less, and the epoxy equivalent is the hydroxyl equivalent of the substituted phenol novolak resin as a raw material plus 75 or less, for example, in the case of an orthocresol novolac type epoxy resin, the epoxy equivalent is Must be 197 or less.

Further, the content of α-glycol was 3.5 (meq / 100
g) or less, preferably 3 (meq / 100 g) or less.

The absorbance of the novolak epoxy resin according to the present invention is 3 (weight / volume) of the novolak epoxy resin.
% Dichloromethane solution was placed in a potassium bromide liquid cell having a cell length of 2 mm, and the number of times of measurement integration was 3 with a Fourier transform infrared spectrophotometer [FT / IR-5M, JASCO Corporation].
Measure infrared absorption spectrum of 00 times, wave number 3570-3600cm
The maximum value of the absorbance at ^-1 is determined by comparing with the blank. Here, the gain at the time of measurement is 1, and the reference correction coefficient is 1.

In addition, 3% (weight / volume)% of novolak type epoxy resin
Is a novolak type epoxy resin 3
Take parts by weight, dissolve it in dichloromethane, and add
It is prepared by making 100 ml.

The novolak type epoxy resin according to the present invention is usually obtained by reacting epichlorohydrin with a novolak resin of a substituted phenol, as described above.In that case, the phenolic hydroxyl group of the novolak resin of the substituted phenol and the epichlorohydrin Glycidyl ether groups are generated based on the dehydrochlorination reaction with, and various other side reactions occur, resulting in various alcoholic hydroxyl groups and various phenolic hydroxyl groups.

Examples of the alcoholic hydroxyl group include those derived from the reaction of glycidol, which is an impurity of epichlorohydrin, with a novolak resin of substituted phenols, and α formed by hydrolysis of a glycidyl ether group once formed.
Those derived from glycol, chlorohydrin ether groups in unreacted epichlorohydrin or glycidyl ether groups formed from unreacted substituted phenols derived from the bond between the phenolic hydroxyl group of the novolak resin,
In addition, when the novolak resin of a substituted phenol is reacted with epichlorohydrin, an alcohol such as methyl alcohol, propyl alcohol, or butanol may be used as a solvent, and may be derived from a hydroxyl group of the solvent.

As a kind of the phenolic hydroxyl group, there is a kind derived from a phenolic hydroxyl group of a novolak resin of a substituted phenol which is not reacted at the time of reacting a novolak resin of a substituted phenol with epichlorohydrin.

In the absorbance measurement by infrared spectrophotometer, 3570-36
In the wave number range of 00 cm ^−1, absorption based on alcoholic hydroxyl groups or phenolic hydroxyl groups appears.

The novolak type epoxy resin according to the present invention satisfies the above conditions, and in the case of orthocresol novolak type epoxy resin, the epoxy equivalent is preferably 197 or less, more preferably 195 or less. Such a novolak type epoxy resin is obtained by reacting a novolak resin of orthocresol having a hydroxyl equivalent of 118 to 122 with epichlorohydrin such that the epoxy equivalent thereof becomes equal to or less than 75 equivalent of the hydroxyl equivalent of the novolak resin of a substituted phenol. Can be obtained by

Absorbance under the above conditions is 0.15 or less, the epoxy equivalent is a hydroxyl group equivalent of the substituted phenol novolak resin as a raw material + Novolak type epoxy resin according to the present invention of 75 or less, needless to say, the remaining phenolic hydroxyl group is small, Since the amount of alcoholic hydroxyl groups, especially α-glycol, is as small as 3.5 (meq / 100 g) or less, especially 3 (meq / 100 g) or less, the cured product is made of various substituted phenol novolak type epoxy resins having conventional absorbances of 0.15 or less. It has extremely excellent heat resistance, crack resistance and water resistance among cured products.

The epoxy resin composition of the present invention can be cured using a curing agent and, if necessary, a curing accelerator.

As the curing agent that can be used in the present invention, usually,
Any of the compounds commonly used as curing agents for this type of epoxy resin can be used. For example, various novolak resins, various aliphatic amines such as diethylenetriamine and triethylenetetramine, and bis (3 Alicyclic amines such as -methyl-4-aminomicrohexyl) methane; various aromatic amines such as metaphenylenediamine, diaminodiphenylmethane and diaminodiphenylsulfone; various polyamide resins or various modified products thereof; maleic anhydride , Phthalic anhydride,
Hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, benzophenonetetracarboxylic dianhydride,
Various acid anhydrides such as pyromellitic anhydride; or dicyandiamide, imidazole, BF ₃ - amine complex, such as such as various latent curing agent for various guanidine derivatives.

The amount of the curing agent used depends on the number of epoxy groups contained in one molecule of the epoxy resin, the number of amino groups or imino groups in the curing agent, the number of active hydrogen groups such as phenolic hydroxyl groups, or the number of acid anhydride groups. An amount near the equivalent is common.

When various compounds as described above are used as a curing agent, a curing accelerator may be further used, if necessary. Examples of the curing accelerator include various tertiary amines such as dimethylbenzylamine; various imidazoles such as 2-methylimidazole; or various organometallic compounds such as amine metal salts; 1,3,5-trihydroxy Examples include polyhydric phenols such as benzene, and of course, any of various known and commonly used curing accelerators can be used.

The epoxy resin composition of the present invention thus obtained includes:
Further, if necessary, various commonly used additive components such as a filler, a colorant, a flame retardant, and a coupling agent can be appropriately compounded.

Among them, silicas, zirconium silicate,
Alumina, calcium carbonate, quartz powder, zircon oxide, talc, clay, barium sulfate, asbestos powder or milled glass, etc. Metal compounds and the like, and only typical representative examples of the release agent include stearic acid, metal salts of stearic acid, natural waxes and synthetic waxes, and the like. Antimony trioxide or hexabromobenzene, etc., if only representative examples are used as the flame retardant, and further, if only typical representative examples are given as the coupling agent, acrylic Examples include silanes, aminosilanes, and epoxysilanes.

In the epoxy resin composition of the present invention, if necessary, other known and commonly used epoxy resins may be used in combination with the specific substituted phenol novolak type epoxy resin. Examples of the epoxy resin that can be used at that time include a bisphenol A diglycidyl ether type epoxy resin and a tetrabromobisphenol A diglycidyl ether type epoxy resin composition.

The epoxy resin composition of the present invention provides a cured product having excellent heat resistance, moisture resistance, chemical resistance, etc., and is therefore required for semiconductor sealing materials, paint insulating varnishes, laminates, insulating powder paints, etc. Electrical insulating materials, laminated boards and prepregs for printed wiring boards, conductive adhesives and adhesives for structural materials such as honeycomb panels, molding materials for electrical components other than semiconductors, GFRP, CFRP and prepregs and resist inks It can be used for such purposes.

〔Example〕

Next, the present invention will be described in detail with reference to examples. In the following, all parts are by weight unless otherwise specified.

Production Example 1 360 g of an O-cresol novolak resin (softening point: 100 ° C., hydroxyl equivalent: 120 g / eq) was dissolved in 2775 parts of epichlorohydrin and 555 g of isopropyl alcohol, and then stirred at 70 ° C.
Then, 690 g of a 20% aqueous sodium hydroxide solution was added dropwise over 8 hours, and the reaction was further carried out for 1 hour. After discarding the aqueous layer, excess epichlorohydrin was recovered by distillation to obtain a reaction product. To this, 1320 parts of methyl isobutyl ketone was added and dissolved, and then 18 g of a 50% aqueous sodium hydroxide solution was added thereto to give 2
After reacting for 1 hour, add 200g of water and discard the lower layer.
After neutralizing by adding 250 g of aqueous sodium phosphate solution, oil-water separation was performed, water was removed from the oil layer by azeotropic distillation, filtration was performed, and methyl isobutyl ketone was distilled off to obtain an epoxy equivalent of 19.
2, melting point 73 ° C, hydrolyzable chlorine 400 ppm, α-glycol 3
meq / 100g The maximum value of the absorbance at a wave number of 3500 to 3600 cm ^-1
An epoxy resin composition (a) of 0.11 was obtained.

Production Example 2 An epoxy equivalent of 195, a melting point of 75 ° C., hydrolyzable chlorine of 420 ppm, α-glycol 3meq / 100 g, and a wave number of 3500 were carried out in exactly the same manner as in Production Example 1 except that 22220 parts of epichlorohydrin were used.
An epoxy resin composition (b) having a maximum absorbance at 33600 cm ⁻¹ of 0.14 was obtained.

Comparative Production Example 1 An epoxy equivalent of 206, a melting point of 77 ° C., hydrolyzable chlorine of 410 ppm, α-glycol 4meq / 100 g, and a wave number of 3500 were carried out in exactly the same manner as in Production Example 1 except that 1388 parts of epichlorohydrin was used.
An epoxy resin composition (c) having a maximum absorbance of 0.20 at に お け る 3600 cm ⁻¹ was obtained.

Comparative Production Example 2 An epoxy equivalent of 198, a melting point of 74 ° C., and hydrolysis were carried out in the same manner as in Production Example 2 except that 2359 g and 416 g of epichlorohydrin (containing 1.5% of glycidol) and fresh epichlorohydrin recovered in Production Example 1 were used, respectively. 390pp of chlorine
m, α-glycol 29 meq / 100 g, and an epoxy resin composition (d) having a maximum absorbance of 0.12 at a wave number of 3500 to 3600 cm ⁻¹ was obtained.

An epoxy equivalent of 199 and a melting point of 74 were obtained in exactly the same manner as in Comparative Production Example 2 except that 1110 parts of isopropyl alcohol was used.
° C, hydrolyzable chlorine 400 ppm, α-glycol 18meq / 100
g, the maximum value of the absorbance at a wave number of 3500 to 3600 cm ^-1 is 0.14
Thus, an epoxy resin composition (e) was obtained.

In addition, any water in the obtained epoxy resin composition
At 0.05% or less, both free sodium ions and chlorine ions were 2ppm or less.

Examples 1-2 and Comparative Examples 1-3 Epicron 1 was added to 100 parts of the epoxy resin composition shown in Table 1.
52-S (Tetrabromo manufactured by Dainippon Ink and Chemicals, Inc.)
Bisphenol A type epoxy resin, bromine content 47%) 16
Part, phenol novolak resin (Bercam TD-
2131 Softening point 80 ° C) 50 parts, quartz powder 350 parts, Curesol C ₁₁
Z (1 part of a hardening accelerator manufactured by Shikoku Chemicals Co., Ltd.), 2 parts of a silicon-based additive, 3 parts of stearic acid, and 1 part of carbon black were added to obtain a compound, and the mixture was mixed at 70 ° C. with a mixing roll machine.
The mixture was kneaded for 10 minutes until homogenous, and pulverized to obtain a molding material.

The molding materials obtained in the above Examples and Comparative Examples were cured at 170 ° C. for 3 minutes, and further cured for 1 minute.
After curing at 60 ° C. for 4 hours, various properties of each cured product thus obtained were measured. The results are shown in Table 1.

As is clear from Table 1, the cured product obtained by using the composition of the present invention is remarkably excellent in all of various properties as compared with the conventional one.

[Effect of the Invention] The cured product obtained from the epoxy resin composition of the present invention has excellent electrical properties, heat resistance, and water resistance.

Therefore, the epoxy resin composition of the present invention is a molding material,
It can be used for a wide range of applications such as casting materials, laminate materials, paints, adhesives, etc., and is extremely useful for sealing electronic components and laminating.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C08G 59/20-59/32 C08L 63/00-63/10

Claims (4)

(57) [Claims] 1. A substituted phenol novolak type epoxy resin having a wavenumber of 3 (weight / volume)% measured in a dichloromethane solution of 3% by weight using an infrared spectrophotometer at a cell length of 2 mm.
The maximum value of the absorbance at 500 to 3600 cm ^-1 is 0.15 or less,
And an epoxy resin composition containing an epoxy resin having an epoxy equivalent of the hydroxyl equivalent of the substituted phenol novolak resin as a raw material plus 75 or less. 2. An ortho-cresol novolak type epoxy resin having a maximum value of absorbance at a wave number of 3500 to 3600 cm ^-1 measured with an infrared spectrophotometer at a cell length of 2 mm for a 3% (w / v) dichloromethane solution. An epoxy resin composition comprising an epoxy resin having an epoxy equivalent of 0.15 or less and an epoxy equivalent of a hydroxyl equivalent of an ortho-cresol novolak resin as a raw material plus 75 or less. 3. An ortho-cresol novolak type epoxy resin having a wave number of 3 (weight / volume) measured with a 3 mm (w / v) dichloromethane solution at a cell length of 2 mm using an infrared spectrophotometer.
The maximum value of the absorbance at 500 to 3600 cm ^-1 is 0.15 or less,
An epoxy resin composition containing the epoxy resin having an epoxy equivalent of 197 or less. 4. A substituted phenol novolak type epoxy resin, which has a wave number of 3 (weight / volume) measured in a dichloromethane solution of 3% (weight / volume) using an infrared spectrophotometer at a cell length of 2 mm.
The maximum value of the absorbance at 500 to 3600 cm ^-1 is 0.15 or less,
And the epoxy equivalent is the hydroxyl equivalent of the substituted phenol novolak resin used as a raw material plus 75 or less, and the α
-An epoxy resin composition containing the epoxy resin having a glycol content of 3.5 (meq / 100 g) or less.