To obtain a dispersion containing no contaminant and suitable as a water-based laminating adhesive suitable for use in contact with a food by reacting a specific polyol component with a diisocyanate component, providing a polyurethane prepolymer, dispersing the resultant prepolymer in water and reacting the prepolymer with the water.
This laminating adhesive for the flexible packaging is an aqueous dispersion obtained by reacting (A) a polyol component having a sulfonated polyester-based polyol having sulfonate groups present in the form of an alkali metallic salt (e.g. the one prepared from monosodium 5-sulfoisophthalate, adipic acid and diethylene glycol) with (B) a diisocyanate component having a diisocyanate compound at ≤90°C temperature in the absence of a solvent, providing (C) a water-dispersible isocyanate-terminated polyurethane prepolymer, then dispersing the component C in (D) water without containing the solvent, reacting the components C with D and thereby extending the chain of the component C.
DAGURASU GUOOSUTO
ROOUERU RINDOKISUTO
SUKOTSUTO REIN
TOOMASU ROORANDO
SONIA SUTAMURAA
PEETAA BOSU
MIKAERU DOKUNIAKU
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