JPH05112699A - Epoxy resin composition for casting - Google Patents

Abstract

PURPOSE:To provide a composition not causing the precipitative separation of iron powder during storage and transportation by compounding a specific liquid epoxy resin, a hydroxyl group-containing organic component, and the iron powder. CONSTITUTION:A composition comprises (A) 100 pts.wt. of a liquid epoxy resin having an all chlorine content of >=0.5wt.% and a viscosity of <=300 poises at 25 deg.C, (B) 0.1-10 pts.wt. of a hydroxyl group-containing liquid organic compound having a viscosity of <=300 poises at 25 deg.C and (C) iron powder, the component C being 60-80wt.% based on all components. A curing agent containing a polyaminoamide compound as a main component is preferable as the epoxy resin curing agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casting epoxy resin composition containing iron powder. In particular, it has excellent storage qualities and hardenability, and is used for repairing various jigs (eg inspection jigs, punching and cutting jigs, etc.), equipment and parts (eg master models, mechanical parts, etc.), and various metals. The present invention relates to a casting epoxy resin composition containing iron powder, which is suitable for manufacturing a resin mold for processing.

[0002]

2. Description of the Related Art Epoxy resin compositions containing metal powder as a filler are already known. However, the conventional epoxy resin composition containing iron powder has a drawback that the iron powder precipitates and separates during storage.

[0003]

DISCLOSURE OF THE INVENTION The present invention is intended to provide an epoxy resin composition for casting which does not cause sedimentation and separation of iron powder during storage and transportation and has good curability.

[0004]

The epoxy resin composition for casting according to the present invention comprises (a) a liquid epoxy resin 100 having a total chlorine content of 0.5% by weight or more and a viscosity at 25 ° C. of 300 poise or less. Parts by weight, (b) 0.1-10 parts by weight of a hydroxyl group-containing liquid organic compound having a viscosity of 300 poise or less at 25 ° C., and (c) iron powder, and the ratio of iron powder is the total resin composition. It is a resin composition which can be hardened by an epoxy resin hardener characterized by being 60-80 weight%.

The "total resin composition" described in the present specification means
Not to mention iron powder, it refers to a total epoxy resin composition containing various other additives but no epoxy resin curing agent.

The epoxy resin used in the present invention has a total chlorine content of 0.5% by weight or more, preferably 1% by weight or more,
It is a liquid epoxy resin having a viscosity of 300 poise or less at 25 ° C. When the total chlorine content is small, the iron powder is liable to settle and separate, resulting in poor storage stability and poor curability. Moreover, when the viscosity is high, the workability of the resin composition is deteriorated. The preferred epoxy resin is bisphenol A
Type liquid epoxy resin and bisphenol F type liquid epoxy resin.

The hydroxyl group-containing liquid organic compound used in the present invention has a viscosity of 300 poise or less. If the viscosity is too high, the workability of the resin composition deteriorates as in the case of the epoxy resin. Preferred hydroxyl group-containing liquid organic compounds are glycol compounds such as ethylene glycol, diethylene glycol and propylene glycol. The content of the hydroxyl group-containing liquid organic compound is 0.1 to 1 with respect to 100 parts by weight of the liquid epoxy resin.
0 parts by weight. If the content ratio of the liquid organic compound is too small, the viscosity of the composition becomes high, and iron powder and the like tend to settle out, and the curability also deteriorates. Further, if the content ratio of the liquid organic compound is too large, the performance of the cured product, particularly the mechanical performance, is deteriorated.

Iron powder is contained in the casting epoxy resin composition of the present invention. The iron powder has the function of increasing the hardness of the resin composition and improving the abrasion resistance. The content ratio of the iron powder is 60 to 80% by weight based on the total resin composition.
If the content ratio is too low, the wear resistance of the cured product cannot be sufficiently improved, and if it is too high, the fluidity of the resin composition decreases and the workability deteriorates. The iron powder preferably has a large content of fine powder.

In addition to the above-mentioned components, the epoxy resin composition for casting according to the present invention may optionally contain a flame retardant, a coupling agent, a thixotropy imparting agent, a reactive diluent, a leveling agent, a lubricant, Various additives such as a thickener, an anti-settling agent, a dispersant, an adhesion-imparting agent, a wetting agent, a dye, a pigment, a rust preventive, and a corrosion inhibitor can be added.

The casting epoxy resin composition of the present invention comprises:
The curing is performed using an epoxy resin curing agent, and as the epoxy resin curing agent, all curing agents generally known can be used. Specific examples of the curing agent include:
Examples thereof include amines, modified amines, polyamide resins, acid anhydrides, imidazoles, etc. Among them, polyamide resins are preferable because they have excellent room temperature curability. As the epoxy resin curing agent, one kind may be used, or two or more kinds may be appropriately used in combination.

The epoxy resin curing agent of the present invention is usually used by mixing it with a casting resin composition, but in the case of a room temperature curable curing agent, immediately before the casting resin composition is used. It is desirable to mix them.

The epoxy resin composition for casting according to the present invention is prepared by appropriately mixing the above-mentioned essential components and additives to be added as necessary, and kneading. For the kneading, for example, a kneader is used. , Rolls, mixers and the like can be used as appropriate.

[0013]

[Examples] Examples and comparative examples will be described in more detail below.

Example 1 100 g of bisphenol A diglycidyl ether (viscosity 180 poise) having a total chlorine content of 1.5% by weight, ethylene glycol 3 g, and iron powder (average particle size 70 μm) 300 g
Was kneaded with a kneader to obtain a composition.

To 100 g of this composition, a polyaminoamide compound (Tomaide 2500, a product of Fuji Kasei Kogyo Co., Ltd.) was added as a curing agent and uniformly mixed, and cured at room temperature for 2 days. Table 1 shows the stability of the resin composition containing no curing agent, the curability of the resin composition containing the curing agent, and the hardness of the cured product.

Example 2 A composition was prepared in the same manner as in Example 1 except that propylene glycol was used in place of the ethylene glycol used in Example 1, and the composition was similarly cured and similarly tested. The results are shown in Table 1.

Comparative Example 1 Instead of the bisphenol A diglycidyl ether having a total chlorine content of 1.5% by weight used in Example 1, bisphenol A diglycidyl ether having a total chlorine content of 0.1% by weight was used.
Otherwise, a composition was prepared in the same manner as in Example 1, and the same test was conducted. The results are shown in Table 1.

Comparative Example 2 A composition was prepared and tested in the same manner as in Example 1 except that 20 g of ethylene glycol was used instead of 3 g of ethylene glycol used in Example 1. The results are shown in Table 1.

Comparative Example 3 A composition was prepared and tested in the same manner as in Example 1 except that ethylene glycol was not used at all. The results are shown in Table 1.

[0020]

[Table 1]

Note to Table 1: * 1 ... Presence or absence of sedimentation after storage at 25 ° C. for 2 months * 2 ... Peak heat generation time and maximum heat generation temperature on 1000 gram scale * 3 ... Shore D hardness

As is clear from Table 1, the compositions of Examples have less sedimentation and excellent curability as compared with the compositions of Comparative Examples.

[0023]

The epoxy resin composition for casting according to the present invention has little settling of iron powder, is excellent in storage stability, and is excellent in curability.

Claims (2)

[Claims] 1. A total chlorine content of 0.5% by weight or more,
Liquid epoxy resin with a viscosity of 300 poise or less at 25 ° C 1
00 parts by weight, (b) 0.1-10 parts by weight of a hydroxyl group-containing liquid organic compound having a viscosity of 300 poise or less at 25 ° C., and (c) iron powder, and the proportion of iron powder is the total resin composition. An epoxy resin composition for casting, which is cured with an epoxy resin curing agent, characterized in that it is 60 to 80% by weight with respect to the product. 2. The epoxy resin composition for casting according to claim 1, wherein the epoxy resin curing agent is a curing agent containing a polyaminoamide compound as a main component.