Control the color difference of injection molded products


Chromatic aberration is a common defect in injection mo […]

Chromatic aberration is a common defect in injection molding. It is not uncommon for the injection molding machine to be scrapped in batches due to the difference in color of the matching parts. There are many factors affecting chromatic aberration, involving raw material resin, color masterbatch (or toner), mixing of color masterbatch with raw materials, injection molding process, injection molding machine, mold, etc. Because of the wide range of exposure, color difference control technology is also recognized as difficult in injection molding. Master one of the techniques.

1. Eliminate the influence of injection molding machine and mold factors

To select an injection molding machine with the same capacity as the injection molding product, it is best to replace the equipment if there is a problem with the dead angle of the injection molding machine. For the mold casting system, the exhaust groove, etc., the color difference can be solved by the maintenance mold of the corresponding part of the mold. The injection molding machine and mold problems must be solved before the production can be organized to reduce the complexity of the problem.

2. Eliminate the influence of raw resin and color masterbatch

Controlling raw materials is the key to completely solving chromatic aberrations. Therefore, especially in the production of light-colored articles, the significant influence of the difference in thermal stability of the raw material resin on the color fluctuation of the product cannot be ignored.

Since most injection molding manufacturers do not produce plastic masterbatch or color masterbatch themselves, the focus can be on production management and raw material inspection. That is to strengthen the inspection of raw materials into the warehouse; the same product in production should be produced by the same manufacturer, the same brand masterbatch and color masterbatch;

For color masterbatch, we must carry out sampling test color before mass production, both the same as the last proofreading, but also in this comparison, if the color difference is not big, can be considered qualified, as the batch color master has a slight color difference, can be The color masterbatch is remixed and then used to reduce the color difference caused by the uneven mixing of the color masterbatch itself. At the same time, we also need to focus on the thermal stability of the raw material resin and color masterbatch. For the poor thermal stability, we recommend that the manufacturer exchange.