PURPOSE: To prepare the titled latex having a double-layer structure and giving a coating film having high gas-barrier property, by the emulsion polymerization of a mixture of vinylidene chloride and a monomer copolymerizable therewith in the presence of a polymer latex obtained by the emulsion polymerization of a mixture of vinylidene chloride, etc.
CONSTITUTION: Latex particles (800W2,000 diameter) having double-layer structure are prepared by (1) carrying out the emulsion polymerization of a monomer mixture composed of 80W92(wt)%, pref. 83W90% vinylidene chloride and 8W20%, pref. 10W17% monomer copolymerizable with vinylidene chloride, and (2) carrying out the emulsion polymerization of 7.5W50pts.wt. of a monomer mixture composed of 94W100%, pref. 96W100% vinylidene chloride and 0W6%, pref. 0W 4% monomer copolymerizable with vinylidene chloride in the presence of latex containing 50W92.5pts.wt. pref. 70W90pts.wt. of the vinylidene chloride copolymer obtained by the step (1).
USE: Food packaging, etc.
ADACHI YOSHIAKI
KOBORI MASAKI
