It means that products delamination like mica sheet, because different material is mixed, especially for different Shrinkage material.

There are a few reasons caused this problem:
1. The melt temperature is too low, material couldn't  conbine well. It may caused products delamination under ejected acting force.
2. The back presure is too low.
3. The material consistency is not so good.
4. Material contains too much water content.
5. Too much recycle material was added in the raw material,because there are so many impurities in recycle material.

The solution are as below:
1. Try to increase hopper temperature and mold temperature.
2. Increase the back presure.
3. To avoid using different material.
4. Dry material.
5. Strictly control the recycle material addition.