PROCESS AND APPARATUS FOR PRODUCING BLOW MOLDED THERMOPLASTIC ARTICLES HAVING IMPROVED WELD STRENGTH

摘要

Weld seams of parisons formed in an inert atmosphere during extrusion followed by blow molding with a blowing gas containing an oxidizing agent are extremely strong when compared with conventional seams formed in the presence of air. By sealing in an inert atmosphere and subsequently blowing the parison with a mixture of nitrogen and fluorine, a container is produced having both high weld seam strength and high levels of impermeability to non-polar hydrocarbons.