Sunstar Giken Kabushiki Kaisha

Sunstar Engineering Pte. Ltd.

Ryuichi Ueda

Masahiro Ito

Masahito Mori

Masaharu Takada

Masaru Sugimori

Kohske Torii

Shingo Tsuno

At least some of the isocyanate groups in the cured polyurethane sealant of this invention have the isocyanurate structure. A moisture-curing sealant composition of the invention comprises an active isocyanato-terminated isocyanate prepolymer containing a polyol component with a molecular weight of 2,000 to 20,000 and an isocyanurating agent. The sealant composition of the present invention is particularly excellent in initial bond strength due to sharp viscosity buildup.

Sealant composition comprising moisture curable isocyanurate containing

A moisture-curing hot-melt adhesive comprises (A) a urethane prepolymer comprising hard and soft segment moieties and having an isocyanate group at the terminus which is prepared by reacting stepwise a polyol having a molecular weight of 1,000 to 8,000 and a thermoplastic saturated polyester polyol having a molecular weight of 1,000 to 6,000, a melting point of 50.degree. C. or higher and a glass transition temperature of 10.degree. C. or higher with an diisocyanate compound in a overall NCO/OH ratio of 1.6 to 3.0, and (B) a urethane prepolymer comprising a soft segment moiety and having an isocyanate group at the terminus which is prepared by reacting a polyol having a molecular weight of not more than 8,000 with a diisocyanate compound in an NCO/OH ratio of 1.6 to 3.0, said component (A) and component (B) being mixed in a ratio of 10:90 to 90:10 by weight. Said adhesive has excellent adhesion and pressure-sensitive adhesion and initial properties and is suitable for adhering various parts in automobile industry and construction industry.

Moisture-curing hot-melt adhesive

Polyurethane adhesive

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Ikeda, Japan

Ryuichi Ueda