How to control the color difference of Standard Injection Molding Machine products?

How to control the color difference of Standard Injection Molding Machine products?



1. Eliminate the influence of Standard Injection Molding Machine and mold factors
  Choose the Standard Injection Molding Machine with the same capabilities as the main injection molding products. If the Standard Injection Molding Machine has problems such as material dead ends, it is best to replace the equipment. The chromatic aberration caused by the gating system and the exhaust groove of the mold can be solved by repairing the mold in the corresponding part of the mold. Before organizing production, the problem of Standard Injection Molding Machine and mold must be solved to reduce the complexity of the problem.

2. Eliminate the influence of raw material resin and masterbatch
  Controlling raw materials is the key to completely solving the color difference. Therefore, especially in the production of light-colored products, the obvious influence of the different thermal stability of the resin raw materials on the color fluctuation of the product cannot be ignored. In view of the fact that most injection molding manufacturers do not produce plastic masterbatch or color masterbatch, you can pay attention to production management and raw material inspection.

  That is to strengthen the inspection of raw materials storage; as far as possible, the same products are produced by the same manufacturer, the same brand of masterbatch and masterbatch; for masterbatch, sampling and color testing should be carried out before mass production, and the same as the last time Compare with this time. If the color difference is not large, it can be considered qualified, just like the color masterbatch has a slight color difference.

  The masterbatch can be remixed and then used to reduce the color difference caused by the uneven mixing of the masterbatch itself. At the same time, we also need to focus on testing the thermal stability of the raw material resin and masterbatch. For products with poor thermal stability, we recommend that the manufacturer replace them.

3. Reduce the influence of barrel temperature on chromatic aberration

  In production, it is often encountered due to the damage and failure of the heating ring or the out-of-control and prolonged burning of the heating control component, which causes the temperature of the barrel to change sharply, resulting in color difference. The chromatic aberration caused by this reason is easy to judge. Generally speaking, the chromatic aberration caused by damage and failure of the heating ring will be accompanied by uneven plasticization.

  However, the heating control part that burns out of control for a long time is often accompanied by gas spots, severe discoloration, and even product coking. Therefore, in production, the heating components should be checked frequently. If the heating components are damaged or out of control, they should be replaced and repaired in time to reduce the occurrence of this color difference.

4. Reduce the impact of injection molding process adjustment
  When the injection molding process parameters need to be adjusted due to non-chromatic aberration reasons, the injection molding temperature, back pressure, injection molding cycle and the amount of master batch should not be changed as much as possible. At the same time, it is necessary to observe the effect of changes in process parameters on color. If color difference is found, it should be adjusted in time.

  Try to avoid using the injection molding process with strong shearing effect caused by high injection speed and high back pressure to prevent local overheating or thermal decomposition causing color difference. Strictly control the temperature of each heating section of the barrel, especially the temperature of the nozzle and the heating part near the nozzle.
5. Grasp the influence of barrel temperature and masterbatch on product color changes

  Before adjusting the color difference, we must also understand the trend of product color with temperature and color masterbatch. With the change of the production temperature or the amount of masterbatch, the color change law of the product is also different. The change rule can be determined through the color test process. Unless the color change rule of the masterbatch is known, it is impossible to quickly adjust the color difference

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