Patent ID: 6248799
Filing Date: 2001-06-19
Classification: A43B,C08J

Abstract:
A process for manufacturing a material based on polyvinylchloride, said process comprising:in a first step, providing a mixed blend of a polyvinylchloride material with at least one of a thermal stabilizer, a co-stabilizer and a plasticizer, thereby to obtain a mixture;in a second step, adding to the mixture a predetermined amount of polymeric microspheres containing a volatile gas, the second step being carried out under a strictly controlled thermal condition in order to essentially avoid both breaking and expansion of said microspheres, and thereby to create a blended composition;in a third step, extruding and granulating the blended composition from the second step, whereby the thermal conditions and the extrusion rate of the extruder are kept under strict control in order to essentially avoid both breaking and expansion of said microspheres, said third step resulting in a granulated material based on polyvinylchloride material containing microspheres which are essentially integral and unexpanded.