Causes and solutions of surface color and gloss defects of injection molds parts

Causes and solutions of surface color and gloss defects of injection molds parts

The injection mold is a tool for producing plastic products; it is also a tool for giving plastic products a complete structure and precise dimensions. The injection mold is composed of two parts, a moving mold and a fixed mold. Injection molding of the mold is a processing method used when mass-producing certain complex-shaped parts. The plastic raw material is injected into the cavity of the injection mold through an injection molding machine, and is cooled and solidified to obtain a molded injection molded part.

Generally, the plastic products obtained by this injection molding method have relatively good gloss and beautiful colors, but in the actual injection production process, many products produced by injection mold factories have relatively large colors and gloss. In addition to the rigid factors of plastic raw materials, colorants and mold surface finish, what other reasons will cause this situation? Today PTJ SHOP will solve this mystery and how to deal with it.

  • (1) Poor finish of the mold, rust on the surface of the cavity, etc., poor mold exhaust.
  • (2) The casting system of the mold is defective, and the cold material well should be enlarged, and the flow channel, polished main channel, shunt channel and gate should be increased.
  • (3) The material temperature and the mold temperature are too low. If necessary, the gate can be heated locally.
  • (4) The processing pressure is too low, the speed is too slow, the injection time is insufficient, and the back pressure is insufficient, resulting in poor compactness and dark surface.
  • (5) The plastic should be fully plasticized, but the degradation of the material should be prevented, the heating should be stable, and the cooling should be sufficient, especially thick-walled.
  • (6) To prevent cold materials from entering the parts, use self-locking springs or reduce the nozzle temperature if necessary.
  • (7) Too much recycled material is used, the quality of plastics or colorants is poor, and the quality of lubricants mixed with water vapor or other impurities is poor.
  • (8) The clamping force should be sufficient.

It can be seen that it takes a lot of effort to produce a high-quality plastic product, not only good plastic raw materials, but also precise processing and production equipment and high-quality high-precision injection molds, coupled with experienced technical operators, plus In the whole production process, enough patience and carefulness can be finally completed.

Plastic Mold
the authorPlastic Mold