Color difference is referred to as a change in color after processing. In other words, there is a color difference of being darker or lighter between the finished product and the original product.Many customers reflect that the finished products often encounter a color difference in color matching production of TPE/TPR.
1. It may be caused by poor dispersion property of the material, or uneven mixing of toner and the main material. While dispersing in the screw rod, the toner may aggregate or the mixing formulation (no adding of diffusing agent) itself is not favorable for toner dispersion to result in color difference.
Solution: Stir thoroughly during the operation, select a surface-active toner to reduce aggregation, or add a diffusing agent to help the toner to disperse.
2. Inaccurate weighing of color masterbatch. As some products are established with specific matching ratios, a slight difference in one or two masterbatch granules may lead to a significant color difference in the finished products.
Solution: Strictly regulate the weighing amount of masterbatch. Try your best to mix the masterbatch and main material thoroughly prior to feeding.
3. Color difference caused by large temperature changes. The heavy metal contents in inorganic toners tend to be higher, but there are no heavy metals in organic toners. In the event of a large temperature difference (over 10℃), the toner can be easily degraded to generate discoloration.
Solution: Try your best to control a stable molding temperature.
4. Discoloration caused by material degradation to result in color difference. This happens in the event of machine shutdown where the screw rod is left with material residue for a long period of time, and the screw rod is not cleaned but proceeded with injection molding of other product.
Solution: Clean the screw rod thoroughly in each machine shutdown.