The solution for the production of pinholes in the processing of modified plastic products. Below I will introduce the reasons and solutions for the production of pinholes in the processing of modified plastic products.
First, the reasons for the poor needle spray of modified plastic products spray processing:
1. When the coating is dried in a state containing bubbles, the bubbles expand and break through the surface of the coating to cause pinholes.
2. The coating solvent erodes onto the modified plastic substrate containing internal stress of the modified plastic parts, and the cracks occur. The solvent is further eroded into the crack, and as the solvent evaporates and vaporizes during the drying process, it breaks through the surface of the coating to produce a pinhole.
Second, the modified plastic products spray processing and poor spraying of the needle eye problem corresponding to the solution:
1. Extend the standing time after seasoning and reduce the viscosity of the coating.
2. Improve the cavity and mold temperature, reduce the injection pressure, increase the injection speed, and switch to a less aggressive solvent. The uncoated molded product is tempered in advance.
