초록

A powder coating process for producing soft, flexible polyurethane films particularly in the form of a surgical glove, wherein low melting crystalline prepolymer particles are powder coated and cured to an essentially non-crystalline film.

대표청구항 ▼

A process for forming a soft, flexible polyurethane film which consists essentially of: (a) fluidizing finely divided particles of a polyurethane prepolymer, said prepolymer having a crystalline melt point in the range of approximately 10°to 45°C., (b) pre-heating a film form to a temperature at whi

A process for forming a soft, flexible polyurethane film which consists essentially of: (a) fluidizing finely divided particles of a polyurethane prepolymer, said prepolymer having a crystalline melt point in the range of approximately 10°to 45°C., (b) pre-heating a film form to a temperature at which said particles will adhere to said form when in contact therewith, (c) immersing said pre-heated form into said fluidized particles such that said particles deposit on said form, (d) heating said form to melt said particles such that said particles flow out into a thin, continuous, essentially pin hole free film, and (e) removing said film from said form; wherein said prepolymer comprises the reaction product of an organic polyisocyanate, a crystalline long chain diol having an average molecular weight of approximately 500 to 5000, a polyhydroxy crosslinking agent and an end blocking agent, wherein the resulting polyurethane elastomer has a 100% modulus less than approximately 250 psi and a 300% modulus between 200 and 500 psi.