Patent ID: 8540901

Claim:
A method for producing an aqueous fluororesin dispersion, wherein a crude aqueous fluororesin dispersion comprising a melt-processable fluororesin particle dispersed in an aqueous medium is subjected to a treatment in contact with an ion exchange resin and a concentration by phase separation in the presence of an electrolyte and/or a nonfluorinated anionic emulsifier to thereby obtain the aqueous fluororesin dispersion, wherein the crude aqueous fluororesin dispersion is brought into contact with the ion exchange resin, and then, after the step of adding the electrolyte and/or the nonfluorinated anionic emulsifier, the concentration by phase separation is carried out, wherein the electrolyte is at least one selected from the group consisting of sulfuric acid, succinic acid, carbonic acid, and salts thereof, and wherein the nonfluorinated anionic emulsifier is one such that a 0.1% (by mass) aqueous solution thereof has a surface tension of not higher than 60 mN/m.