JP2002356604A - Flame-retardant epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant epoxy resin composition without halogen, antimony, non phosphorus. SOLUTION: This flame-retardant epoxy resin composition contains as essential components a multifunctional epoxy resin (1) having at least two epoxy groups in a molecule, an epoxy resin curing agent (2), and phenothiazine (3).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a flame-retardant epoxy resin composition containing substantially no halogen, antimony or phosphorus.

[0002]

2. Description of the Related Art Epoxy resins have been used in various fields because of their excellent heat resistance, electrical properties, mechanical properties, adhesiveness and the like. In an epoxy resin composition requiring flame retardancy, a halogen-based flame retardant, an antimony or a phosphorus-based flame retardant is mainly used for achieving flame retardancy.

[0003]

In recent years, with increasing awareness of environmental issues, there has been an increasing demand for reducing substances that pollute the environment. Along with this, halogen is suspected of producing dioxin-related substances depending on the incineration conditions during incineration, antimony is suspected of carcinogenicity, and phosphorus-based flame retardants can not deny suspected environmental pollution. Therefore, there is an increasing demand for a flame-retardant composition that does not contain these substances. An object of the present invention is to provide an environment-friendly flame-retardant composition substantially free of halogen, antimony, and phosphorus in view of such circumstances.

[0004]

Means for Solving the Problems As a result of research for solving the above problems, the present inventors have found that flame retardancy can be obtained by adding a specific additive to an epoxy resin and a curing agent. Invented the invention.

That is, the present invention provides: 1.1) a polyfunctional epoxy resin having two or more epoxy groups in one molecule; 2) an epoxy resin curing agent; and 3) a flame-retardant epoxy resin composition comprising phenothiazine as essential components. , 2. Total 1 of polyfunctional epoxy resin and epoxy resin curing agent
2. The flame-retardant epoxy resin composition according to the above item 1, which contains phenothiazine in an amount of 1 part by weight or more based on 00 parts by weight 3. The flame-retardant epoxy resin composition according to the above 1 or 2, wherein the epoxy resin curing agent is a curing agent having two or more phenolic hydroxyl groups in one molecule. 4. The flame-retardant epoxy resin composition according to any one of claims 1 to 3, which is prepared for electric / electronic parts. 0.25% by weight of hydrolyzable chlorine in epoxy resin
5. The flame-retardant epoxy resin composition according to any one of the above items 1 to 4, which is: A cured product of the flame-retardant epoxy resin composition according to any one of the above items 1 to 5.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The polyfunctional epoxy resin used in the present invention is an epoxy resin having two or more epoxy groups in one molecule, and may be any commonly used one. Specific examples of polyfunctional epoxy resins that can be used (hereinafter, simply referred to as epoxy resins) include bisphenol A, tetramethylbisphenol F, bisphenol F, bisphenol S, bisphenol K, biphenol, tetramethylbiphenol, hydroquinone, methylhydroquinone, and dimethylhydroquinone. , Trimethylhydroquinone, di-ter. Butyl hydroquinone, resorcinol, methyl resorcinol, catechol, methyl catechol, dihydroxynaphthalene, dihydroxymethylnaphthalene, glycidylated compounds such as dihydroxydimethylnaphthalene, phenols, or condensates of naphthols with aldehydes, phenols or naphthols and xylylene Examples thereof include condensates with glycols, condensates of phenols or naphthols with bismethoxymethylbiphenyl, condensates of phenols with isopropenyl acetophenone, and glycidylated products such as a reaction product of phenols and dicyclopentadiene. These can be obtained by a known method.

The above phenols include phenol, cresol, xylenol, butylphenol, amylphenol, nonylphenol, catechol, resorcinol, methylresorcinol, hydroquinone,
Examples thereof include phenylphenol, bisphenol A, bisphenol F, bisphenol K, bisphenol S, biphenol, and tetramethylbiphenol.

Examples of naphthols include 1-naphthol, 2-naphthol, dihydroxynaphthalene, dihydroxymethylnaphthalene, dihydroxydimethylnaphthalene, trihydroxynaphthalene and the like.

Further, aldehydes include formaldehyde, acetaldehyde, propylaldehyde, butyraldehyde, valeraldehyde, caproaldehyde, benzaldehyde, chlorbenzaldehyde, bromobenzaldehyde, glyoxal, malonaldehyde, succinaldehyde, glutaraldehyde, adipine aldehyde, Examples thereof include melinaldehyde, sebacinaldehyde, acrolein, crotonaldehyde, salicylaldehyde, phthalaldehyde, and hydroxybenzaldehyde, and these are used alone or in combination of several kinds.

Further, when the epoxy resin composition is used for electricity and electronics, it is preferable that the composition has a low hydrolyzable chlorine concentration. A preferred epoxy resin in this case is a solution in which the epoxy resin is dissolved in dioxane and treated with 1N KOH under reflux for 30 minutes. It is 0.20% by weight, more preferably 0.15% by weight or less.

The epoxy resin curing agent (hereinafter simply referred to as a curing agent) may be any one which is usually used as a curing agent for an epoxy resin, and may be a phenolic curing agent, a naphthol curing agent, an amine curing agent, or an acid anhydride curing agent. Agents are mainly used. Specific examples of the phenol-based curing agent and naphthol-based curing agent having a phenolic hydroxyl group include bisphenol A, tetramethylbisphenol F, bisphenol F, bisphenol S, bisphenol K, biphenol, tetramethylbiphenol, hydroquinone, and methylhydroquinone. , Dimethylhydroquinone,
Trimethylhydroquinone, di-ter. Butyl hydroquinone, resorcinol, methyl resorcinol, catechol, methyl catechol, dihydroxynaphthalene, dihydroxymethylnaphthalene, glycidylated compounds such as dihydroxydimethylnaphthalene, phenols, or condensates of naphthols with aldehydes, phenols or naphthols and xylylene Examples include condensates with glycols, condensates of phenols or naphthols with bismethoxymethylbiphenyl, condensates of phenols with isopropenylacetophenone, and reaction products of phenols with dicyclopentadiene. Examples of the amine-based curing agent include triethylenetetramine, tetraethylenepentamine, N-aminoethylpiperazine, isophoronediamine, xylylenediamine, phenylenediamine, diaminodiphenylsulfone, and the like. Acid anhydride curing agents include phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride Etc. are exemplified. These curing agents are used alone or as a mixture of several kinds, and those having a phenolic hydroxyl group are preferred.

Examples of the above-mentioned phenols, naphthols and aldehydes are the same as those exemplified for the above-mentioned polyfunctional epoxy resin.

The amount of the curing agent used is preferably from 0.3 to 1.5 equivalents, more preferably from 0.5 to 1.3 equivalents, based on the epoxy groups in the epoxy resin. If less than 0.3 equivalents, unreacted epoxy groups increase, and if more than 1.5 equivalents,
The amount of the unreacted curing agent increases, and the thermal and mechanical properties deteriorate, which is not preferable.

The phenothiazine contained in the epoxy resin composition of the present invention may be a reagent or an industrially used one. The phenothiazine is generally added in an amount of 1 part by weight or more, preferably 1 to 50 parts by weight, more preferably 3 to 30 parts by weight, based on 100 parts by weight of the total of the epoxy resin and the curing agent. If the amount is small, the effect of imparting flame retardancy is small. When the amount of addition increases, the possibility of adversely affecting fluidity, curability, water absorption and the like increases.

A curing accelerator can be added to the epoxy resin composition of the present invention, if necessary. As a curing accelerator, phosphines such as triphenylphosphine and bis (methoxyphenyl) phenylphosphine;
Examples thereof include imidazoles such as methylimidazole and 2-ethyl-4-methylimidazole, and tertiary amines such as trisdimethylaminomethylphenol and diazabicycloundecene. The amount of the curing accelerator used is epoxy resin 10
The amount is preferably 0.2 to 6.0 parts by weight, more preferably 0.4 to 4.0 parts by weight, per 0 parts by weight.

Further, the epoxy resin composition of the present invention may optionally contain an inorganic filler, a pigment, a release agent, a silane coupling agent, a softener, and the like. In particular, the addition of a non-flammable inorganic filler has the effect of further improving the flame retardancy of the present composition, and as long as the workability and physical properties after curing are not impaired, a large amount should be added in terms of flame retardancy. Is desirable. Examples of the non-combustible inorganic filler include hydroxides such as aluminum hydroxide, magnesium hydroxide, and iron hydroxide, zinc stannate, silica, alumina, calcium carbonate, aluminum nitride, and silicon nitride.

The epoxy resin composition of the present invention can be obtained by uniformly mixing the components at a predetermined ratio. The epoxy resin composition of the present invention can be easily made into a cured product by a method similar to a conventionally known method. For example, an epoxy resin, a curing agent and a phenothiazine, and if necessary, a curing accelerator, an inorganic filler, a pigment, a release agent, a silane coupling agent, a softening agent, etc.
The epoxy resin composition can be obtained by mixing the mixture at an extruder, a roll, a kneader or the like at a temperature of ° C.

The obtained epoxy resin composition is molded using a casting machine, a transfer molding machine or the like.
The cured product of the present invention can be obtained by post-curing at a temperature of 2 to 10 hours.

The epoxy resin composition of the present invention can be suitably used for electric and electronic parts. In particular,
It can be used for sealing of semiconductors, bonding and casting of laminated boards and electric / electronic parts.

[0020]

The present invention will be described in more detail with reference to the following examples. Also, in the examples, unless otherwise specified, parts indicate parts by weight.

Example 1, Comparative Example 1 The compositions shown in the column of "composition of composition" in Table 1 were uniformly mixed with a mixing roll to obtain an epoxy resin composition.
This composition was crushed and tablets were obtained on a tablet machine. The obtained tablet is transferred using a transfer molding machine.
The test piece was molded into a 10 × 4 × 90 mm test piece. This test piece was post-cured at 180 ° C. for 6 hours. The specimen was held vertically by a clamp, and the flame of the burner was set to 19 m.
m of blue flame at the center of the lower end of the test piece.
mm for 10 seconds. After the flame contact, release the burner and measure the duration of combustion. Immediately after the flame is extinguished, the flame is immediately contacted for 10 seconds, the burner is released, and the combustion duration is measured. The average quenching time of each of the five samples is shown in the column of “Physical Properties of Cured Product” in Table 1. In addition, the numerical value of the column of "composition of a composition" of Table 1 represents a part.

The used epoxy resin, curing agent and curing accelerator are shown below. 1. Epoxy resin EOCN-1020 (glycidylated product of condensate of cresol and formaldehyde, epoxy equivalent 197 g / e
q. , Manufactured by Nippon Kayaku Co., Ltd.) Curing agent PN-80 (phenol novolak, hydroxyl equivalent 105
g / eq. , Manufactured by Nippon Kayaku Co., Ltd.) 3. Hardening accelerator TPP: triphenylphosphine (manufactured by Junsei Chemical Co., Ltd.) Phenothiazine (manufactured by Junsei Chemical Co., Ltd.)

Table 1 Examples Comparative Examples 11 11 Composition of Formulation EOCN 65.1 65.1 PN-80 34.9 34.9 TPP 0.65 0.65 Phenothiazine 10-Physical Properties of Cured Product Burning Time (Seconds) First flame 5 8 Second flame 10 16 Total 15 24 (7)

[0024]

As can be seen from Table 1, the epoxy resin composition of the present invention has a cured product having a burning duration of
The composition is considerably shorter than that for comparison, is environmentally friendly, and is useful for electrical and electronic parts having excellent flame retardancy.

Claims (6)

[Claims] 1. A flame-retardant epoxy resin composition comprising 1) a polyfunctional epoxy resin having two or more epoxy groups per molecule, 2) an epoxy resin curing agent, and 3) phenothiazine. 2. The flame-retardant epoxy resin composition according to claim 1, which comprises phenothiazine in an amount of 1 part by weight or more based on 100 parts by weight of the total of the polyfunctional epoxy resin and the epoxy resin curing agent. 3. The flame-retardant epoxy resin composition according to claim 1, wherein the epoxy resin curing agent is a curing agent having two or more phenolic hydroxyl groups in one molecule. 4. The method according to claim 1, which is prepared for electric / electronic parts.
4. The flame-retardant epoxy resin composition according to claim 3. 5. An epoxy resin having a hydrolyzable chlorine content of 0.2.
The flame-retardant epoxy resin composition according to any one of claims 1 to 4, which is 5% by weight or less. 6. A cured product of the flame-retardant epoxy resin composition according to any one of claims 1 to 5.