JPH0655547A - Molding method - Google Patents

Abstract

PURPOSE:To perform conveniently and automatically anti-static treatment on the outer surface of a molded item by using an air contg. an antistatic agent for air blowing of a mold. CONSTITUTION:An antistatic agent is incorporated in compressed air used when burrs, remaining gas and volatile content generated while molding are removed from a mold. In addition, the antistatic agent and a release agent may be used in parallel in some cases. It is possible thereby to perform automatically antistatic treatment on the outer surface of a molded item while molding processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the prevention of static electricity on molded articles.

[0002]

2. Description of the Related Art Conventionally, a plastic molded article is generally excellent in electric insulation, so that it is easily charged when it is rubbed or separated from the superposed state. As a result, dust is likely to be attached, impairing the aesthetic appearance and not exhibiting its original function. In addition, there is a risk of electric shock to workers at the manufacturing site and sometimes causing a fire.

As countermeasures therefor, there are a bricking method in which an antistatic agent is added as one of the compounding ingredients of a molding material and a coating method such as spraying on a molded article. Was expected.

[0004]

Therefore, the present invention provides a method for easily and automatically performing antistatic processing on the outer surface of a molded product during molding.

[0005]

SUMMARY OF THE INVENTION The present invention is a molding method made in view of the above-mentioned problems, and is characterized by using air containing an antistatic agent for air blow of a mold.

Air blow is a mold cleaning for removing burrs, residual gas, volatiles and the like generated in molding such as direct pressure molding, transfer molding and injection molding from a mold by using air compressed by a compressor or the like. Is one means.

As the antistatic agent contained in the air of the air blow for cleaning the mold, anionic compounds such as alkyl sulfates, alkyl aryl sulfates, alkyl phosphates and alkyl amine sulfates, quaternary ammonium salts, Quaternary ammonium resins, cations such as imidazolines, sorbitans, ethers, amines and amides, nonionics such as ethanolamides, amphoteric systems such as betaines, molding materials, molding conditions , And can be used as appropriate in consideration of differences in applications. The amount used is 1 m ³ of air
It is preferably used in the range of 0.01 to 50 g.
This is because if it is less than 0.01 g, the antistatic effect of the molded product is not sufficient, and even if it is used in excess of 50 g, no remarkable difference due to these antistatic agents can be confirmed.

It is also possible to blow air into the mold using compressed air containing a release agent in the same manner as these antistatic agents. In this case, the antistatic property of the molded product and the releasability of the molded product from the mold can be improved.

As the releasing agent, liquid silicone,
It is used by mixing finely powdered silicone, metal stearate soap, a fluorine-based compound and the like with air. The amount used is preferably in the range of 0.01 to ³⁰ g per 1 m ³ of air. This is because if the amount is less than 0.01 g, the burr and the release of the molded product are not sufficient, and even if the amount exceeds 30 g, a remarkable difference in the releasability cannot be confirmed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In the air blow of the embodiment, after molding, the mold is opened and the molded product is removed, and then air compressed by a compressor or the like is blown from the hole provided in the mold to the cavity and its peripheral portion. .

As shown in the perspective view of the mold shown in FIG. 1, holes 3 and 5 are respectively formed in the flat mold surface near the outer periphery of the cavity 2 of the mold 1 and the convex portion 4 formed on the flat mold surface. Arrangement, a similar hole (not shown) is also arranged in the mold 6,
It is preferable to use these holes 3 and 5 to perform air blowing as indicated by arrows A, B, and C, respectively. Air blows indicated by arrows A and B are performed alternately. These holes 3 and 5 are formed as through holes for the mold, and are collectively arranged and connected to the air pipe 7. The air containing the antistatic agent and the release agent is sent to the air pipe 7 by being compressed by a compressor or the like, and is heated when passing through the through hole of the mold heated for molding. Therefore, air blowing using this air significantly reduces the cooling of the mold, and continuous molding can be performed under stable molding conditions. At the same time, the number of defective products is greatly reduced.

The cross-sectional shape of the holes 3 and 5 may be circular, elliptical, polygonal such as triangular or quadrangular, or any other shape. Further, the number of holes to be formed per location is not particularly limited and may be one. Further, the arrangement is not particularly limited to one row, and a flower pattern having small diameter holes around a large diameter circular hole may be used.

Further, depending on the angles of the holes 3 and 5, it is possible to accurately aim and efficiently remove a portion where burr is likely to adhere or a portion where gas is likely to remain.

By a method of cleaning a mold, in which air containing a release agent is blown from the holes formed on the surface of the mold to a mold portion where unwanted burrs and gas are likely to be generated,
Self-cleaning is easy and continuous automatic molding is possible. In addition, by using a hole provided with a proper angle of the hole at a short distance from the mold cavity, it is possible to take out a molded product having no knockout pin mark by air blow.

[0016]

[Function] By including the antistatic agent in the air of the air blow, the burrs produced by the molding are removed from the mold by the air blow, and at the same time, the antistatic agent is applied to the surface of the air blown mold. Therefore, the surface of the next molded article can be subjected to the antistatic treatment simultaneously with the molding, which is simple and automatic.

[0017]

According to the present invention, it is possible to easily and automatically perform antistatic processing on the outer surface of a molded product during molding. Therefore, it is possible to obtain a molded product to which dust or the like is unlikely to adhere.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

[Explanation of symbols]

 1, 6 Mold 2 Cavity 3, 5 Hole 4 Projection 7 Air piping

Claims (1)

[Claims] 1. A molding method characterized in that air containing an antistatic agent is used for air blowing of a mold.