| 摘要 |
PROBLEM TO BE SOLVED: To provide a process for producing an aqueous composition containing a phenolic resin and desirably used in surface coating, which process is characterized in that the aqueous solution obtained by the process contains no organic solvent and does not contain a specified or larger amount of fluorotitanic acid. SOLUTION: The process for producing the aqueous composition comprises the steps of: reacting a phenolic polymer or copolymer, desirably, a polyvinylphenol with a base, desirably, an alkali metal hydroxide in water to form a phenoxy salt, reacting the aqueous solution containing the salt at 20-100 deg.C in the presence of an amine, desirably, a sec. amine, an aldehyde, a ketone, or a mixture thereof, adding an acid to the obtained reaction mixture to neutralize the remaining base and to make the resin water-soluble by reaction with the amine, admitting the aqueous solution containing the obtained reaction mixture into a column of an acidic cation exchange (of an H+ form) to remove base ions such as Na ions therefrom, and thereby obtaining an aqueous solution containing no organic solvent and not containing 0.18 wt.% or above fluorotitanic acid.
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