Currently using 65 durometer PVC and getting bubbles in the injected outsole

From Jose G…Recreational Footwear in Mexico


Question:
Currently using 65 durometer PVC and getting bubbles in the injected outsole.


Answer:
Although PVC is typically not hydroscopic, the presence of moisture on the surface can lead to inconsistent processing and the requirement for adjustments in the Injection Molding Machine.  
The use of a Hot Air Dryer will remove the surface moisture and keep the PVC at a consistent temperature such that machine process parameters do not require as much monitoring and result in a more consistent product.
There are also IMM parameters that can lead to bubbles in the PVC.  Please contact your machine vendor for suggestions that they may have.


Mark Haynie...Sales Manager – Dryer Products, Novatec, Inc.