METHOD FOR MANUFACTURING THIN-WALLED ARTICLES FROM CRYSTALLINE THERMOPLASTIC MATERIAL BY THERMOFORMING

摘要

The present invention relates to an improved method for manufacturing thin-walled articles from crystalline thermoplastic material by thermoforming a web of said material. The method includes providing a web of said material wherein the inner core of the web is at a temperature higher than the upper limit of the critical crystalline melting temperature range while the outer surface regions of the web are at a temperature lower than the lower limit of the critical crystalline melting temperature range. The web is then subjected to thermoforming with or without heating of the outer surface regions.