JPH06322236A - Resin composition for jig and tool - Google Patents

Abstract

PURPOSE:To provide a resin compsn. for jig and tool which gives a cured article free from surface or inside voids even when mixed and cured without being deaerated under a reduced pressure by compounding an epoxy resin with a curative for the resin, microballoons, and a sepcific silicone surfactant. CONSTITUTION:The compsn. is prepd. by compounding a liq. epoxy resin of a phenol ether or glycidyl ether type with a curative for the resin, 5-58vol.% microballoons with a specific gravity of 0.15-0.6 and particle diameters of 5-300mum, and 0.01-5wt.% silicone surfactant comprising a polyoxyalkylsiloxane- polyoxyalkylene block copolymer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an epoxy resin composition for jigs and tools. More specifically, the present invention relates to an epoxy resin composition for jigs, which does not have large and small uneven voids that can be visually observed on the surface or inside of the cured product even when mixed and arranged without curing under reduced pressure and cured. .

[0002]

2. Description of the Related Art Conventionally, epoxy resin has been used in the vehicle industry, the electric appliance industry, etc. for making jigs and tools such as models and simple models. Various methods such as casting and gel coating are used for making jigs and tools, but as one of the methods for making jigs and tools, epoxy resin is placed on a substrate such as wood or foam, and the cured product is cut and cured. May create tools. This method has an advantage over other methods in that a thick tool can be easily produced. The epoxy resin composition used for this purpose requires workability and cutting workability, and a paste-like or putty-like composition containing hollow microspheres and optionally other fillers is used. Since the composition has an extremely high viscosity, it is easy to entrap air bubbles during mixing and stirring of constituents and during arranging work, and coarse air bubbles with a diameter of 1 mm or more are usually generated in the cured product, which is inconvenient as a tool material. It will be As a measure for reducing the generation of voids due to the coarse bubbles, methods such as adding an antifoaming agent and defoaming under reduced pressure during mixing and stirring are generally performed.

[0003]

However, the filling resin containing hollow microspheres, in particular, has a poor defoaming property, and even if the defoaming is performed in a high vacuum, the bubbles do not easily come out, and the size of the resin inside or on the surface of the cured product is large or small. There was a problem that because of the irregular shaped voids, repairs were required and aesthetics were adversely affected. Further, when defoaming is performed for a long time using an epoxy resin and a curing agent having a long curing time, the hollow microspheres are likely to be unevenly distributed due to the difference in specific gravity between the resin and the hollow microspheres, and a uniform cured product is obtained. There was a problem that it was difficult to obtain. The present invention is
It is an object of the present invention to obtain an epoxy resin composition which can be a cured product with less voids and uneven distribution of fillers, which are inconvenient for jigs and tools.

[0004]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the inventors of the present invention have found that a specific defoaming operation in a composition can be carried out without a special defoaming operation such as defoaming under reduced pressure. The present invention has been found out that by adding an additive, a cured product dispersed as fine bubbles can be obtained to the extent that there is no inconvenience when it is used as a jig or tool. That is, the present invention provides an epoxy resin composition for jigs and tools comprising an epoxy resin (A), an epoxy resin curing agent (B) and hollow microspheres (C), which comprises a block copolymer of polyoxyalkylsiloxane and polyoxyalkylene. An epoxy resin composition for jigs and tools, characterized in that a silicone-based surfactant (D) is present.

In the present invention, the epoxy resin (A) is (A-1) phenol ether type epoxy resin [bisphenol A type liquid epoxy resin, bisphenol F].
Type liquid epoxy resin, bisphenol AD type liquid epoxy resin, etc .; (A-2) Glycidyl ester type liquid epoxy resin [diglycidyl phthalate, etc.]; (A-3) Glycidyl amine type liquid epoxy resin [aniline glycidyl ether Ter, o-toluidine glycidyl ether,
Tetraglycidyldiaminodiphenylmethane glycidyl ether, etc.]; (A-4) Polyglycidyl ether type liquid epoxy resin [1,6 hexamethylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, polyethylene glyco- Ludiglycidyl ether, polypropylene glycol-diglycidyl ether, glycerin polyglycidyl ether, trimethylo-
Lupropane polyglycidyl ether and the like], and these may be used alone or in combination of two or more.

Among the examples exemplified as (A) above, (A-1) and (A-4) are preferable, and (A-1) is particularly preferable.

The epoxy resin curing agent (B) is not particularly limited as long as it is generally used for curing an epoxy resin and is liquid at room temperature. Specific examples of (B) include (B-1) polyamine-based [polyalkylenes such as ethylenediamine, tetramethylenediamine, hexamethylenediamine, and other alkylenediamines, diethylenetriamine, triethylenetetramine, pentaethylenehexamine, bis (hexamethylene) triamine, and the like. Alkylene (alkylene carbon number 2 to 6) polyamine, aromatic-containing aliphatic amines such as xylylenediamine, aromatic amines, etc.]; (B-2) modified polyamine system [(B-1) polyamine; Epoxide, unsaturated compound adduct, reaction product with methylol compound, eutectic mixture of metaphenylenediamine, and solution of diaminodiphenylmethane in liquid amine or diluent]; (B-3) Polyamidoamine system [(B-1) Polyamine, Tole Oil Fatty Acid, Soybean Oil Fatty Acid Condensation products of fatty acids such as polymerized fatty acid];
(B-4) acid anhydride system [dodecenyl succinic anhydride, methylhexahydrophthalic anhydride trimellitic anhydride, etc.];
(B-5) catalyst system [benzyldimethylamine, 2-methylimidazole, etc.]; (B-6) polymercaptan system [trioxanetrimethylenemercaptan, etc.] and the like, and these may be used alone or in combination of two or more. Can be used.

Of the above-mentioned examples (B), the preferable ones are (B-1), (B-2) and (B-3).

The hollow microspheres (C) include (C-1) inorganic hollow microspheres (hollow microspheres made of glass, shirasu, etc.) and (C-2) organic microballoons (phenol).
Hollow microspheres made of a thermosetting resin such as a resin and an epoxy resin, or a thermoplastic resin such as an acrylonitrile-vinylidene chloride copolymer). Among these, preferred are hollow microspheres made of glass as a raw material and hollow microspheres made of a phenol resin as a raw material.

The specific gravity of (C) is not particularly limited, but is usually 0.15 to 0.6, preferably 0.2 to 0.4.
If the specific gravity is less than 0.15, the hollow microspheres are easily broken during mixing, and if it exceeds 0.6, the machinability is poor. Also, (C)
The particle size of is usually 5 to 300μ, preferably 10 to 180μ
Is. If the particle size is less than 5 μm, the mechanical strength of the obtained molded product tends to decrease, and if it exceeds 300 μm, the microspheres are easily separated, and a uniform cured product is difficult to obtain.

The compounding amount in the composition (C) is usually 1
It is 5 to 85% by volume, preferably 20 to 80% by volume. If the blending amount is less than 15% by volume, the machinability is poor,
If it exceeds 85% by volume, the mechanical strength of the cured product will decrease.

The silicon-based surfactant (D) is composed of a block copolymer of polyalkylsiloxane and polyoxyalkylene, and a particularly preferred block copolymer is a polyoxyalkylene chain branched to the polyalkylsiloxane. It is a linked copolymer.
Examples of the polyoxyalkylene chain include a polyoxyethylene chain, a polyoxypropylene chain and a polyoxyethylene propylene (block or random) chain. The block copolymer is obtained, for example, by subjecting a polyalkylsiloxane having at least one active hydrogen group in the molecule to a polyaddition reaction of ethylene oxide and / or propylene oxide.

The amount of (D) added is usually 0.01 to 5% by weight, preferably 0.1 to 2% by weight, based on the weight of the liquid component in the composition of the present invention. If the addition amount is less than 0.01% by weight, the effect of preventing the formation of coarse voids in the cured product is poor, and if it exceeds 5% by weight, the elastic modulus of the cured product decreases.

The composition of the present invention comprises (A), (B) and (C)
And (D) may be an essential constituent component, and other additives may be used if necessary. Other additives include, for example, reactive diluents (polypropylene glycol diglycidyl ether, polyhydric alcohol glycidyl ether, etc.), inorganic powders (talc, titanium oxide, calcium carbonate, etc.) colorants (bengara, etc.), curing Examples include accelerators (phenol and the like) and viscosity modifiers (dibutyl phthalate and the like).

In the present invention, (C), (D) and, if necessary, other additives may be premixed with (A) and / or (B). When (A) and (B) are mixed, You may add.

[0016]

The present invention will be further described with reference to the following examples, but the present invention is not limited thereto. In the following, the parts are parts by weight.

Example 1 400 parts of liquid epoxy resin [trade name Epikote 828, manufactured by Yuka Shell Epoxy Co., Ltd.], reactive diluent [polypropylene glycol diglycidyl ether, trade name Chemiole EP-400P, Sanyo Chemical Industry Co., Ltd. Co., Ltd.] 75
Part, glass balloon [trade name Q cell 300, manufactured by Asahi Glass Co., Ltd.] 200 parts and talc [trade name soapstone C, manufactured by Nippon Mistron Co., Ltd.] 325 parts are mixed in a mixer, and [main ingredient A] Got Liquid polyamide resin [Product name Polymide L-504, Sanyo Chemical Industry Co., Ltd.] 47
5 copies, glass balloon [Product name: Glass Bubbles Q Cell 3
00, Asahi Glass Co., Ltd.] 200 parts and talc [Product name: Soapstone C, Nippon Mistron Co., Ltd.] 325
The parts were mixed with a mixer to obtain [Curing agent B]. Next, 400 parts of the [base material A1], 240 parts of the [curing agent B1] and 0.64 part of a silicon-based surfactant [trade name SH-194, manufactured by Toray Dow Corning Co., Ltd.] are mixed by stirring with a mixer, Assemble on release paper (10 cm in length × 10 cm in width × 5 cm in height) and cure at 25 ° C for 15 hours to obtain a cured product [1].
Got

Example 2 400 parts of liquid epoxy resin [trade name Epikote 807, manufactured by Yuka Shell Epoxy Co., Ltd.], phenol resin ball
[Product name BJO-930, Union Carbide Co., Ltd.
Made] 300 parts and talc [Product name Soapstone C,
[Mistron Japan Co., Ltd.] 300 parts were mixed with a mixer to obtain [Main ingredient A2]. Then, the [main agent A2] 500
Part, aromatic amine [trade name Kayahard A-A, manufactured by Nippon Kayaku Co., Ltd.] 70 parts, diluent [trade name Nicanol DS, manufactured by Mitsubishi Gas Chemical Co., Inc.] and silicone surfactant [Product name SH-194, manufactured by Toray Dow Corning Co., Ltd.]
Mix 6 parts with a mixer and pour it on release paper (vertical 1
(0 cm × width 10 cm × height 5 cm) was cured at 25 ° C. for 15 hours and further at 80 ° C. for 4 hours to obtain a cured product [2].

Comparative Example 1 A comparative cured product [3] was obtained in the same manner as in Example 1 except that the silicon-based surfactant was not added.

Comparative Example 2 A comparative cured product [4] was obtained in the same manner as in Example 2 except that the silicon-based surfactant was not added.

Comparative Example 3 The composition used in Comparative Example 2 was subjected to 2 mm under reduced pressure of 10 mmHg.
A cured product [5] was obtained in the same manner as in Comparative Example 2 except that the mixture was stirred and mixed for 0 minutes.

Performance Test Each of the cured products obtained in Examples 1 and 2 and Comparative Examples 1 to 3 was cut with a band saw and the cut surfaces were compared. The cured products [1] and [2] were in the surface condition. Was uniform and no voids were observed, but it was observed that many large and small irregular voids including coarse voids having a diameter of 1 mm or more were formed in the cured products [3] to [5]. In the cured product [5], it was found that hollow microspheres were partially distributed.

[0023]

EFFECT OF THE INVENTION The composition of the present invention becomes a paste or putty when mixed and stirred.
Since the bubbles are dispersed so small that they cannot be seen, there is no void where the obtained cured product can be seen, and there is no need for repairs such as filling large voids (voids) due to bubbles as a jig and tool, and the aesthetic appearance is also good. . Because of the above effects, the composition of the present invention is useful for epoxy resin jigs and tools that place importance on appearance, especially jigs and tools created by plating cutting.

Claims (2)

[Claims] 1. An epoxy resin composition for jigs and tools comprising an epoxy resin (A), an epoxy resin curing agent (B) and hollow microspheres (C), which comprises a block copolymer of polyoxyalkylsiloxane and polyoxyalkylene. An epoxy resin composition for jigs and tools, wherein a silicone-based surfactant (D) is present. 2. The content of (C) in the composition is
The composition according to claim 1, which is 20 to 80% by volume.