JPS62275178A - Flame-retardant adhesive composition - Google Patents

Abstract

PURPOSE:To provide the title compsn. having excellent adhesion and workability while retaining flexibility inherent to org. resins, comprising a specified phosphorus compd., a polyester resin, an epoxy resin and a curing agent. CONSTITUTION:100pts.wt. phosphorus compd. (A) having a phosphorus content of not lower than 5wt%, an epoxy equivalent of 150-500 and at least one epoxy group per molecule [e.g., glycidyl-alpha-methyl-beta-di(methoxy)phosphinyl propionate] is blended with 150-300pts.wt. polyester resin (B) having an m.p. of 30-220 deg.C and a glass transition temp. of 60-80 deg.C, 100-300pts.wt. epoxy resin (C) consisting of 30-80wt% halogen-contg. epoxy resin and 70-20wt% epoxy resin contg. no halogen and 10-60pts.wt. curing agent (D) (e.g., phthalic anhydride). The mixture is dissolved in an org. solvent.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a flame-retardant adhesive composition, and more specifically to an electronic separate device that requires flame retardancy. In related fields,
The present invention relates to a flame-retardant adhesive composition suitable for adhering metal foil to glass epoxy plates, adhering metal foil to plastic films, and adhering electronic parts to substrates.

[Conventional technology]

As a flame-retardant adhesive composition, one in which a large amount of a bromine compound, an inorganic flame retardant, or both of these are blended into an organic resin is known.

[Problem that the invention seeks to solve]

However, conventional flame-retardant adhesives contain large amounts of bromine compounds and inorganic flame retardants, which may inhibit the flexibility of organic resins and reduce their adhesive strength. Furthermore, dispersing non-technical flame retardants requires sophisticated techniques, which may impair workability.

On the other hand, phosphorus compounds are well known as flame retardants for plastics, and it is conceivable that they could also be applied to flame retardant adhesives. However, even if a known phosphorus compound is added to an adhesive, flame retardancy may be exhibited, but the adhesive force may be reduced.

It is an object of the present invention to provide a flame-retardant adhesive composition that improves these problems, maintains the flexibility of an organic resin, has excellent adhesive strength, and is also excellent in workability.

(Means for solving the problem) The present invention comprises a phosphorus compound (A) having one or more epoxy groups in one molecule, a polyester resin (B), an epoxy resin (C), and a curing agent (D ) The present invention relates to a flame-retardant adhesive composition comprising:

The phosphorus compound in the present invention has one or more epoxy groups in one molecule. The phosphorus content of this compound is preferably 5 wt% or more. Roughly preferably 8
~20wt%. If the phosphorus content is too low, it may be difficult to obtain the desired flame retardancy, and if it is too high, it may be difficult to synthesize. Moreover, the epoxy equivalent of this compound is preferably 150 to 500. It is preferably 250 to 350. If the epoxy layer is too small, curing tends to proceed too much and the adhesive strength decreases, and if it is too large, the adhesive strength may decrease due to insufficient curing.

Specific examples include glycidyl-α-medyl-β-di(methoxy)phosphinylpropionate HsO glycidyl-α-methyl-β-di(butoxy)phosphinylpropionate 4H90 glycidyl-α-ethyl- Examples include β-di(methoxy)bosphinylpropionate H30.

The polyester resin used in the present invention is not particularly limited, but has a melting temperature (m, p.

) is 30 to 220°C, and the glass transition temperature is 160°C.
-so'c are preferably used. Specific examples of the vine polyester resin used in the present invention include those synthesized from the following acid components and glycols.

Examples of acid components include terephthalic acid, isophthalic acid,
naphthalene-2,6-dicarboxylic acid, naphthalene-1,
Examples include 5-dicarboxylic acid, sebacic acid, adipic acid, maleic acid, fumaric acid, trimesic acid, trimellitic acid, pyromellitic acid, and aromatic dicarboxylic acids are particularly preferred.

Glycol components include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, polytetramethylene glycol, bisphenol-ethylene oxide adduct, bisphenol A-propylene oxide adduct, etc. .

A polyester resin obtained by copolymerizing such an acid component and a glycol component can be used. Preferably, polyester resins that are soluble in common organic solvents such as acetone, methyl ethyl ketone, chloroform, benzene, trichloroethylene, carbon tetrachloride are preferred. To give a rough example, a polyester resin consisting of 40 to 60 mol% of isophthalic M and 140 to 60 mol% of terephthal as acid components, and 35 to 55 mol% of ethylene glycol and 45 to 65 mol% of neopendel glycol as glycol components;
A polyester resin containing 55 to 75 mol% of terephthalic acid, 25 to 45 mol% of sebacic acid or adipic acid as an acid component, and 30 to 50 mol% of ethylene glycol and 50 to 70 mol% of neopentyl glycol as a glycol component.

Roughly 100 parts of polyethylene terephthalate, 10 to 80 parts of glycols such as diethylene glycol, triethylene glycol, polyethylene glycol, triethylene glycol, polyethylene glycol, or a mixture thereof, and further neopentyl glycol,
A polyester resin obtained by adding 5 to 40 parts of a chain-branched glycol such as an ethylene oxide adduct or a bisphenol A-propylene oxide adduct to bisphenol and transesterifying it can also be used.

The epoxy resin used in the present invention includes epoxy resins that do not contain halogen or epoxy resins that contain halogen, and these may be used alone or in combination.

The halogen-free epoxy resin used in the present invention may be any epoxy resin as long as it has two or more epoxy groups in one molecule, but suitable examples include novolac type epoxy resin, dimer acid There are type epoxy resins, polyglycol type epoxy resins, etc.

The halogen-containing epoxy resin used in the present invention may be any resin as long as it has an epoxy group and a halogen atom in one molecule, but preferred examples include bisphenol-type brominated epoxy resin, novolac-type brominated epoxy resin, etc. Examples include epoxy resins and ether-type brominated epoxy resins. Specifically, "Epicote 1050" manufactured by Shell Chemical Co., Ltd. and "'DER" manufactured by Dow Chemical Co., Ltd.
542", BRE N-S" manufactured by Nippon Koyaku Co., Ltd.
and so on.

If it is desired to further improve flame retardancy, it is effective to use a halogen-containing epoxy resin as the epoxy resin, or to use a combination of a halogen-containing epoxy resin and a halogen-free epoxy resin.

In this case, it is preferable to use 30 to B□wt% of the halogen-containing epoxy resin among all the epoxy resins. When the content of the halogen-containing epoxy resin exceeds 8 Qwt%, the adhesive strength tends to decrease. Moreover, if it is less than 30 wt%, there may be no effect of improving flame retardancy.

Examples of the curing agent used in the present invention include known epoxy resin curing agents such as amines, acid anhydrides, and imidazoles, but acid anhydrides are preferred from the viewpoint of heat resistance.

Although the amounts of the above-mentioned components of the adhesive composition according to the present invention are not particularly limited, they are preferably used in the following proportions.

That is, it is preferable to mix 150 to 350 parts of the polyester resin with respect to 100 parts (parts represent parts by weight; see below) of the phosphorus compound having an epoxy group, and more preferably,
It is 200-300 parts.

If the amount of polyester resin is too small, the adhesive strength may be reduced, and if it is too large, the flame retardancy may be reduced. Epoxy resin is 1
00 to 300 parts, more preferably 15
0 to 250 copies. If the amount of epoxy resin is too small, the adhesive strength may decrease, and if it is too large, the flame retardance may decrease.

The curing agent is 10 to 60 parts, preferably 30 to 4 parts.
It's part 0.

If there is too little curing agent, the epoxy resin will not harden and the adhesive strength will tend to decrease. If the amount is too high, curing may progress too much and adhesive strength may decrease. In addition, other components may be added to the extent that the adhesion and flame retardant properties are not deteriorated. Examples include acrylic resin and acrylonitrile.
Organic resins such as butadiene rubber, 5b203, 80 (○
Examples include inorganic particles such as H)3.

Next, a method for producing the flame-retardant adhesive of the present invention will be explained. First, a predetermined amount of an organic solvent is added to and dissolved in a predetermined amount of a phosphorus compound having an epoxy group. Subsequently, predetermined amounts of polyester resin, epoxy resin, and curing agent are added and dissolved to obtain a flame-retardant adhesive composition.

The thus obtained flame-retardant adhesive composition of the present invention can be used for adhesion of metal foils to glass epoxy plates, adhesion of metal foils to plastic films, electronic devices, etc., where flame retardancy is required. Can be used to bond components to substrates.

(Method of Measuring Characteristics and Evaluating Effects) Methods of measuring characteristic values and evaluating effects of the present invention are as follows.

Flame retardancy: After coating the adhesive on the metal foil, it is cured by heat treatment at 150'C for 15 hours. The film thickness is approximately 100μ. After curing, it was peeled off from the bottom of the gold and subjected to a combustion test in accordance with the UL-94 standard. UL-94 standard indicates flame retardancy as V-○, V
It is ranked into four categories: -1, V-2, and HB, ■-
○ has the best flame retardancy. Next, V-1, V-2, H
It is similar to B. Those inferior to HB were evaluated as having no flame retardancy.

Adhesiveness: Approximately 25 μm of adhesive was applied onto the polyimide film, and after drying, roll pressure bonding (roll temperature 120°C, roll speed: 1 m/min, roll pressure: 2 kCJ/
Cm) Shita. Next, it was cured by heat treatment at 150'C for 15 hours. Thereafter, the force required to peel off the copper foil in a 90° direction from the surface of the substrate at a speed of 50 mm/min was measured. Practically speaking, an adhesive force of about 1 (kg/Cm) or more is required.

[Examples] Example 1 Glycidyl-α-methyl-β-di(butoxy)phosphinylpropionate [manufactured by Ohe Kagaku Co., Ltd., 100 parts]
500 parts of methyl ethyl ketone was added and dissolved. Rani: 250 parts of ``Vylon 300'' (polyester resin) [Toyobo Co., Ltd. 1], 100 parts of ``BREN-8'' (brominated epoxy resin) [manufactured by Nikki Kayaku Co., Ltd.], and ``Epicoat 152''. (Epoxy resin) 11,120 parts of Shell Chemical Co., Ltd. (Shell Chemical Co., Ltd.) were added and dissolved. 30 parts of phthalic anhydride (hardening agent) was added to the colander and stirred thoroughly. The adhesive has a concentration of 54.5 wt% and a viscosity of 3.5 (PS/25°C
)Met. This adhesive exhibited flame retardancy of 1.2 of the UL-94 standard, and had an adhesive strength of 1.3 (kL!/cm).

Example 2 500 parts of dimethylformamide was added and dissolved in 100 parts of glycidyl-α-methyl-β-di(butoxy)phosphinylpropionate.

200 parts of Zarani "Vylon 200" (polyester resin) [manufactured by Toyobo Co., Ltd.] and "D E R542" (brominated epoxy resin) [11120 part of Dow Chemical Co., Ltd.]
and 130 parts of "Epicote 871" (epoxy resin) [manufactured by Shell Chemical Co., Ltd.] were added and dissolved. Furthermore, 30 parts of phthalic anhydride (hardening agent) was added and stirred well. The adhesive has a concentration of 49゜□wt% and a viscosity of 4.2 (PS/25
°C).

This adhesive exhibits flame retardancy of UL-94 standard V-2,
The adhesive strength was 1.2 (kq/cm).

Comparative Example 1 ``Byron 300'' 250 parts and ``B RE N -S''
500 parts of methyl ethyl ketone was added to 250 parts of "Epicote 152" and 120 parts of "Epicote 152" and dissolved therein.

30 parts of phthalic anhydride was added to this and stirred well.

The adhesive has a concentration of 54.5 wt% and a viscosity of 2.7 (PS/
25°C). This adhesive does not have the flame retardancy that defines the UL standard, and its adhesive strength is only 0.2 (kq/cm).

Comparative Example 2 To 100 parts of triphenyl phosphate (phosphorus compound), 5
00 parts of methyl ethyl ketone was added and dissolved. 250 copies of “Zarani Byron 300” and “BREN-3”
100 parts of "Epicoat 152" were added and dissolved. 30 parts of phthalic anhydride was added and stirred well. Adhesive (concentration: 54.5 wt%, viscosity: 3.0
(PS/25°C) This adhesive has UL-9
It showed flame retardancy of 4 standards V-2, but the adhesive strength was 0.4
It was small (kwa/cm).

(Effects of the Invention) The present invention relates to a flame-retardant adhesive composition, and has the following excellent effects.

(1) Because a specific phosphorus compound is used, both flame retardancy and adhesive strength are extremely excellent.

(2) The adhesive is homogeneous, has excellent workability, and has no drawbacks such as inhibiting flexibility.

Claims (3)

[Claims] (1) A hardener characterized by comprising a phosphorus compound (A) having one or more epoxy groups in one molecule, a polyester resin (B), an epoxy resin (C), and a curing agent (D). Flammable adhesive composition. (2) The flame-retardant adhesive composition according to claim (1), wherein the epoxy resin (C) is a halogen-containing epoxy resin. (3) The flame-retardant adhesive composition according to claim (1), wherein the epoxy resin (C) consists of a halogen-containing epoxy resin and a halogen-free epoxy resin.