摘要:
A PTFE laminate which contains a PTFE sheet retaining a high specific gravity and has sufficient adhesion strength; and a PTFE-based backing sheet reduced in permeability to liquid chemicals. The laminate is produced by fusion-bonding a PTFE sheet to a film or sheet of a fusible resin such as PFA, with a layer of fine PTFE particles interposed therebetween or without the layer, and then subjecting the laminate to a treatment in which it is prevented from rapidly cooling. Thus, the average specific gravity of the PTFE sheet is kept at 2.175 or higher.
摘要:
A large block-like molded article free from strain and residual stress can be obtained by a production method comprising the steps of compression molding polytetrafluoroethylene powder to form a preformed article and firing the resulting preformed article while being rotated. A film, a sheet, etc., having less curl and crease can be obtained by cutting the molded article.
摘要:
The present invention aims to provide a modified polytetrafluoroethylene fine powder capable of providing a stretched body having high strength, a small pore size, and excellent homogeneity. The modified polytetrafluoroethylene fine powder of the present invention has non-melt-processability, has a standard specific gravity of 2.155 or lower, includes 0.015 mol% or more of a polymer unit derived from perfluoro(methyl vinyl ether) in all the monomer units, is obtained by emulsion polymerizing tetrafluoroethylene and at least the perfluoro(methyl vinyl ether) in the presence of a fluorosurfactant having a LogPOW value of 3.4 or lower, and has an extrusion pressure of 20.0 MPa or lower.
摘要:
A polytetrafluoroethylene molded product formed by calcination molding, which is resistant to deformation. The molded product is produced by molding a polytetrafluoroethylene powder using compression molding to form a pre-molded product and then calcinating the pre-molded product while rotating it. This polytetrafluoroethylene molded product can be used for reducing the loss of material during the course of cutting from a molded product in a block form to a film or sheet.