Several Methods of Making a Light-weight Orthopedic Casting Tape (2)
The second method of making a light-weight orthopedic casting tape, comprising the steps of:
mixing a polyisocyanate compound, a reactive hydrogen compound, and a filler to form a composite mixture; coating said composite mixture on a light-weight scrim while the polyisocyanate compound and the reactive hydrogen compound are at most only partially reacted and while the composite mixture's viscosity is low enough so that the composite mixture can spread out on the scrim; and then allowing said polyisocyanate compound and said reactive hydrogen compound to further react, thereby forming a water-curable isocyanate-functional prepolymer and thereby increasing the viscosity of said composite mixture to an extent that the composite mixture resists pooling during storage, wherein the ratio of the volume of said filler divided by the volume of said water-curable isocyanate-functional prepolymer is greater than 0.4. Dusting additional amounts of said filler onto the surfaces of said coated scrim.
