PREVENTION OF SCUM DEVELOPMENT FROM AQUEOUS DISPERSION OF FLUOROPOLYMER

摘要

PROBLEM TO BE SOLVED: To effectively prevent scum development over a long period in the subject aqueous dispersion useful for e.g. coating of a base material with a small amount of a complex salt-forming agent, by adding a complex salt-forming agent to an aqueous dispersion of fluoropolymer under acidic conditions followed by making the system alkaline. ;SOLUTION: (B) A complex salt-forming agent such as an aromatic or aliphatic carboxylic acid (salt) or an acid of an alkylenediamine (salt) is added to (A) an aqueous dispersion of fluoropolymer comprising a fluoropolymer such as (modified) polytetrafluoroethylene or tetrafluoroethylene-perfluoropropyl vinyl ether copolymer, a nonionic surfactant and water under acidic conditions (pref. at ≤pH5) followed by making the component A alkaline. It is preferable that the amount of the component B to be used is at least equimolar to the iron, chromium contained in the component A.;COPYRIGHT: (C)1998,JPO