Stretched PTFE film with multiple extension in the third direction and its prepn

• Main Author: QINJUN ZHOU
• Format: Patent
• Language: English
• Published: 01.01.2003
• Edition: 7
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

The present invention features that ePTFE is polydirectionally extended in vacuum sucking mode or constant-temperature high-pressure blowing mode along its third axis so as to increase the air content between node and fiber, increase the strength of node and fiber and increase thickness. After being extended, it is surface heat treated and its temperature is reduced to adhered cloth acceptable temperature before being adhered to cloth with adhesive. If it is not adhered to cloth instantly, it is cooled quickly to maintain its thickness in optimal state and wound in central winding mode with winding tension regulated to minimum to prevent thickness decrease in lower part.