Corresponding to the processing of injection molded products, you will encounter problems like this, the product size is good, but the gloss of the product is indeed unqualified, which leads to scrapped products processed from the injection molded parts. : There are problems with injection molds, production, and design.

1. In the injection molding production process

There are several options to try, and the gloss can be changed by adjusting the mold temperature, packing / maintaining pressure, filling speed and material temperature. In most cases, these adjustments will not have a big impact, and will reduce the overall production process window, thereby increasing the possibility of other problems. Therefore, find a robust process for the part and maintain the surface finish of the cavity mold.

2. In injection mold

When dealing with gloss problems, do not change the surface finish of the mold steel as soon as you come up. Instead, you must first adjust the process parameters to change the gloss of the product. Lower temperature molds, colder melts, lower Packing / holding pressure and lower filling speeds may make your plastic parts shine brighter. The reason for this is that the mold temperature is low, the applied pressure is small, and the plastic does not replicate the microscopic details of the mold steel surface finish.

On the contrary, the higher the injection mold temperature and the melt temperature, the higher the shrinkage / maintenance pressure, and the faster the filling speed, the darker your parts will be. The speed and the resulting shear force have a much greater effect on the viscosity of the material.

On the other hand, if the surface gloss of the product is too high, you can consider reducing the surface polish of the mold steel surface or blasting the mold cavity. Both of these methods will create small pits in the steel, which will increase the surface area, which will allow the injection molded product to absorb more light, thus making your parts appear darker.

3. In terms of injection product design

Another major issue related to gloss is the design of the product, especially where the wall thickness of the product changes. When the wall thickness changes, it is difficult to maintain the uniform gloss of the parts. Due to the difference in flow patterns, the thinner wall sections will not be under too much plastic material pressure, and as a result, the gloss in this area will be higher. Insufficient exhaust will also produce inconsistent surface gloss. Depending on the material and process, insufficient exhaust will cause dark spots and bright spots.

The above three points are important factors that affect the gloss of injection-molded products. As long as the injection-molding manufacturers take these issues into consideration before producing products, they can avoid the problem of gloss of injection-molded products.