Seamless endless belt and process for manufacturing same

摘要

A seamless endless belt is manufactured by biaxially stretching a tube of a polyether-ether-ketone resin while inflating the tube at a temperature above the glass transition temperature of the resin by below the melting point of the resin, optionally thermosetting the stretched tube at 150-320 DEG C while relaxing it at a rate of relaxation of 5-30% and then cutting the resultant tube in round slices. The stretched tube may be laminated with a tube of a thermoplastic polyurethane resin to form a laminate tube of a polyether-ether-ketone resin in the outer and inner tubes with an intermediate tube of a thermoplastic polyurethane resin. A seamless endless tube is manufactured from the laminate tube by heating above the melting point of the polyurethane resin whereby the outer and inner tubes of the polyether-ether-ketone resin are thermoset while being relaxed and the intermediate tube of the polyurethane is molten and integrally bonded to the outer and inner tubes. The belts have heat-resistance, dimensional stability at a high temperature and mechanical strength and can be used as conveyor belts.