JPS6270414A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain an epoxy resin composition which can give a colorless transparent cured product which does not discolor for a long time and is good in processability, by mixing an epoxy resin with an organic polybasic acid anhydride, a cure accelerator and a specified organophosphorus compound. CONSTITUTION:To a resin composition comprising an epoxy resin (a), an organic polybasic acid anhydride (b) and a cure accelerator (c), 0.1-20wt%, based on the total weight of the components (a)-(c), organophosphorus compound of the formula is added. In the formula, R1 and R2 are each a halogen, or an alkyl, aryl or aralkyl group which may be substituted with a halogen or an alkyl group, x and y are each 0 or 1-3, R3 is a residue derived by removing the hydroxyl groups from an organic compound having m hydroxyl groups and m is 1-10. As the epoxy resin, a colorless or light-color one is particularly suitable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an epoxy resin composition that provides a cured product that is colorless and transparent and does not easily change color over a long period of time.

[Prior art]

By combining epoxy resins with various curing agents, cured products with excellent performance can be obtained. In other words, cured epoxy resins have excellent heat resistance, water resistance, chemical resistance, electrical properties, mechanical strength, dimensional stability, flexibility, etc., and are therefore useful for paints, adhesives, electrical equipment materials, laminates, molded products, etc. Widely used industrially for structural materials, fiber processing agents, etc.

Recently, it has been proposed that its properties can be used for optical purposes such as manufacturing optical lenses, prisms, etc., and sealing light emitting diodes, etc. In this case, it is particularly important to avoid coloring of cured products over time and devitrification phenomena. Improvements are required.

[2] Conventional methods using epoxy resins, organic acid anhydride curing agents, and tertiary amines or organic acid salts thereof as curing accelerators, organic phosphites, hindered phenols, etc. Although methods have been proposed in which a compound such as a compound or a bluing agent is added, the results are still unsatisfactory.

Furthermore, as a method for improving these, a method of adding an organic phosphorus compound represented by the following formula (A) or (B) has been proposed (Japanese Patent Laid-Open No. 57-205418).

0f( [In the formula, R4-R8 hydrogen, halodane, or carbon number 1-1
0 monovalent aliphatic or aromatic substituents, R4-
R8 may be the same or different. [Problems to be solved by the invention] According to the results of the study by the present inventor, the above proposed method solves the following problems:
Compared to the conventional known technology, the epoxy resin composition and the cured product obtained therefrom are superior in the coloring prevention effect, but the organic phosphorus compounds represented by formulas (A) and (B) are There is a problem in compatibility with each constituent component and composition, making it inconvenient in compounding operations.Furthermore, when epoxy resin compositions are used in the optical field, further improvement in the coloring prevention effect is desired. there was.

[Means to solve the problem]

The present inventor has made extensive studies in response to such requests for improvement, and as a result, has arrived at the present invention.

That is, the present invention provides an epoxy resin composition consisting essentially of (a) an epoxy resin, (b) an organic polybasic acid anhydride, and (c) a curing accelerator, [wherein R1 and R2Fi] an alkyl group, an aryl group, or an aralkyl group, which may be substituted with a rhodane atom or an alkyl group, each independently an integer of 1 to 3,
The residue of an organic compound having 6 m hydroxyl groups, excluding the hydroxyl group, is dried and m is 1 to 10, preferably 1.
Kuke 1-6. More preferably, each integer of Fi1 to Fi4 is shown. ] The organic phosphorus compound represented by the above (a
An epoxy resin composition K is characterized in that it contains 0.1 to 20 parts of In based on the total amount of components 3 to (c).

The resin composition of the present invention is extremely effective in preventing discoloration and deterioration of transparency during storage, molding, and long-term aging of the molded product. It has good compatibility with its constituent components, so operations such as blending, processing, and molding are easy, and uniform, good quality molded products can be obtained, and when used for optical system purposes in various applications. It is extremely advantageous.

The organic phosphorus compound represented by the general formula (I) is
It is manufactured according to the method described in JP-45397.

That is, O-phenylphene represented by formula (II)
Hydroxy group-containing organic compounds can be obtained from the compound represented by ``puppy'', which is obtained by reacting phosphorus trichloride with phosphorus trichloride.
In the case of -valent alcohols and phenols with low molecular weight (low boiling point), they are produced using the 1n superposition reaction formula, but !(,, - (If OT()m has a relatively high content or is a polyvalent hydroxy compound, the first compound (2) and an appropriate monovalent hydroxy compound.

Suitably, the compound of formula (1) is reacted with phenol, and a hydroxy compound of R3-(OH)rn is added thereto and heated.
Compounds of formula (I) are advantageously obtained by carrying out an exchange reaction with phenol.

-In each of the above reaction formulas, R1r R2* R5r X +
)' and m The above formula (same as the meaning in I1) For example, the following organophosphorus compound can be obtained by the method described in -F. (However, 1. When x = y = 0, the brackets in the structural formula From 1 mole of formula (IV) and decyl alcohol] to 2 moles of formula (IV) and 1 mole of 1,1-bis(4-hydroxy-2-methyl-5-t-butylphenyl)butane to (3 ) Formula 0v) 1 mol and 2.4-di-t-butylphenol 1 mol to (4) Formula ■ 1 mol and 2-t-butyl-4-cresol 1
From 2 moles of formula (5) QV) and 1 mole of 2.5-di-t-butylhydroquinone, the organic phosphorus compound is It is used in an amount of 0.1 to 20 liters, preferably 0.3 to 5 liters, particularly 0.5 to 1.5 liters, and the compatibility is extremely good.

Known epoxy resins are used as the epoxy resin in the present invention, but in particular, in view of the characteristics of the effects of the present invention,
Colorless or light colored ones are suitable.

Typical epoxy resins [7] include bisphenol A,
Bisphenol type obtained from bisphenol F etc. and epichlorohydrin, cycloaliphatic type, glycidyl ester type of polybasic acid such as tetra- or hexahydrophthalic acid, phenol type etc. Examples include polyglycidyl ether types of lac and long chain polyols.

For organic polybasic acid anhydrides and 1-, phthalic anhydride.

Examples include tetra- or hexahydrophthalic anhydride, methylnadic anhydride, dodecylsuccinic anhydride, chlorendic anhydride, adipic anhydride, maleic anhydride, pyromellitic anhydride, trimellitic anhydride, and the like. These acid anhydrides are preferably colorless to light-colored and sufficiently refined.

As curing accelerators, benzylmethylamine, pyridine, 2.4.6-)lis(dimethylaminomethyl)phenol (DMP-30), K-603 (DMP-3
0 (tris 2-ethylhexoate salt), triamylammonium phenolate, sodium hexanetriolate, 1,8-diazobicyclo(5,4,0)undecene-7, and the like.

The resin composition of the present invention also includes known diluents, fillers,
Bulking agents, dyes, plasticizers, etc. can be added depending on the purpose of use.

The epoxy resin composition of the present invention provides a good cured product under commonly used curing conditions. That is, the normal curing temperature is 8
It is several minutes to 202 hours at 0 to 150°C, but 120-1
Even if rapid curing is performed at 50° C., it exhibits a sufficient coloring prevention effect.

〔Example〕

Next, an example (b) of the effect of preventing discoloration of a cured product using the epoxy resin composition of the present invention will be described.

(Test method) Anhydrous methyl hexahydrophthal y11oop (or 90
g), 1 g (or 0.5.9 g) of curing accelerator and 2 g of the compound of general formula (I) according to the invention, if necessary, in an amount of about 50 g).
``CK heating and mixing to prepare hardening agent liquid.

A uniform resin solution was obtained by mixing with 100 g of epoxy resin to obtain a cured product with a thickness of 4 m, a width of 151 m, and a length of 150+ m.The mixture was poured into a mold and heated at 130° C. for 30 minutes to cure. The cured product was then taken out from the mold and visually evaluated for coloring and transparency. In addition, the obtained cured product was left for 1,000 hours at 100°C and then evaluated.For comparison, triphenylphosphite and 9,10-dihydro-9-oxa-10 were added as additives.
-Phosphaphenanthrene-10-oxide and the case without additive were also tested.

(Evaluation method) ◎: Colorless and transparent O: Transparent but slightly colored Δ: Transparent but slightly colored ×: Considerable coloring The test results are shown in Table 1.

That is, when the epoxy resin composition of the present invention is cured, the cured product is colorless and transparent, and its properties are not easily impaired even after a long period of time t~ at high temperatures.

Claims (1)

[Scope of Claims] 1. An epoxy resin composition consisting essentially of (a) an epoxy resin, (b) an organic polybasic acid anhydride, and (c) a curing accelerator, in which the general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) [In the formula, R_1 and R_3 are each independently a halogen atom, an alkyl group, or an aryl group that may be optionally substituted with a halogen atom or an alkyl group. Alternatively, an aralkyl group, x and y are 0 or an integer of 1 to 3, R_3
represents a residue of an organic compound having m hydroxyl groups, excluding hydroxyl groups, and m represents an integer of 1 to 10. ] An epoxy resin composition characterized in that the organic phosphorus compound represented by the formula is contained in an amount of 0.1 to 20% by weight based on the total amount of the components (a) to (e).