Safety cast

Abstract

Safety cast compositions for the prevention of thermal injury are provided basically comprising a curable casting material, a flexible substrate coated or impregnated with the casting material and a thermochromic material. Methods for using the safety cast to prevent cast burns in patients in need of immobilizing a body member are also provided.

1 . An orthopedic casting material comprising:
 (a) a curable casting matrix,   (b) a flexible substrate coated or impregnated with the curable casting matrix and;   (c) a thermochromic material.   
     
     
         2 . The orthopedic casting material according to  claim 1  wherein the curable casting matrix is a synthetic resin selected from the group consisting of hexcelites, isocyanate-functional prepolymers, alkoxysilane terminated prepolymers, polyurethane prepolymers, cyanoacrylate prepolymers, epoxy resins, thermoplastic resins, ethylene acrylic acid ester copolymers, ethyl vinyl acetate copolymers, and mixtures thereof. 
     
     
         3 . (canceled) 
     
     
         4 . The orthopedic casting material according to  claim 2 , wherein the curable casting matrix comprises isocyanate functional prepolymer. 
     
     
         5 . The orthopedic casting material according to  claim 1  wherein the flexible substrate comprises fibers selected from the group consisting of acrylic fibers, fiberglass, polyester fibers, polypropylene fibers, polyaramide fibers, polyamide fibers, carbon fibers, glass fibers, polyethylene fibers, polyacrylonitrile copolymer fibers, cotton fibers, wool fibers, flax fibers, rayon fibers, and mixtures thereof. 
     
     
         6 . The orthopedic casting material according to  claim 1 , wherein the flexible substrate comprises fiberglass. 
     
     
         7 . The orthopedic casting material according to  claim 1  further comprising a non-thermochromic dye or pigment, or mixture thereof. 
     
     
         8 . The orthopedic casting material according to  claim 1 , wherein the thermochromic material is selected from the group consisting of reversible or non-reversible thermochromic dyes, thermochromic pigments, thermochromic liquid crystals, and mixtures thereof, which are capable of producing a visible indication in the casting material when the casting material reaches or exceeds a predetermined temperature at which the thermochromic material undergoes a change in its color state. 
     
     
         9 . The orthopedic casting material according to  claim 8 , wherein the thermochromic material is operative to change from one color to another color, from a color to colorless, or from colorless to a color, at the predetermined temperature. 
     
     
         10 . The orthopedic casting material according to  claim 8 , wherein the predetermined temperature is from about 20° C. to about 60° C. 
     
     
         11 . The orthopedic casting material according to  claim 10 , wherein the predetermined temperature is from about 40° C. to about 48° C. 
     
     
         12 . The orthopedic casting material according to  claim 8 , wherein the thermochromic material changes color reversibly. 
     
     
         13 . The orthopedic casting material according to  claim 8 , wherein the thermochromic material changes color irreversibly. 
     
     
         14 . The orthopedic casting material according to  claim 1 , wherein the thermochromic material is provided dispersed in a binder medium. 
     
     
         15 . The orthopedic casting material according to  claim 1 , wherein the casting material comprises microcapsules containing the thermochromic material. 
     
     
         16 . The orthopedic casting material according to  claim 15 , wherein the microcapsules contain from about 0.01 to about 50% by weight of the thermochromic material. 
     
     
         17 . The orthopedic casting material according to  claim 15 , wherein the microcapsules have a particle size of from about 1 to about 75 μm. 
     
     
         18 . The orthopedic casting material according to  claim 1 , wherein the curable matrix comprises the thermochromic material. 
     
     
         19 . The orthopedic casting material according to  claim 18 , wherein the casting material comprises the thermochromic material in a range from about 0.001 to about 15% by weight of said casting material. 
     
     
         20 . The orthopedic casting material according to  claim 18 , wherein the thermochromic material is provided as an aqueous slurry of microcapsules comprising the thermochromic material encapsulated in a colorless polymer. 
     
     
         21 . The orthopedic casting material according to  claim 1 , wherein the flexible substrate comprises the thermochromic material. 
     
     
         22 . The orthopedic casting material according to  claim 3 , wherein the curable casting matrix further comprises a binder and a red non-thermochromic dye or pigment, the casting matrix containing the thermochromic material, and the thermochromic material comprises a blue thermochromic dye or pigment capable of exhibiting a color change from blue to colorless at about 43° C. to 48° C. 
     
     
         23 . The orthopedic casting material according to  claim 1 , wherein the flexible substrate is impregnated with a moisture curable synthetic casting matrix comprising a prepolymer of an aromatic polyisocyanate and a polyol, a binder, a blue thermochromic material with a color change at a predetermined temperature of between 43° C. to 48° C. from blue to colorless. 
     
     
         24 . The orthopedic casting material according to  claim 1 , wherein said thermochromic material comprises a first thermochromic material capable of producing a first visible indication in the casting material when the casting material reaches or exceeds a first predetermined temperature at which the first thermochromic material undergoes a change in its color state, and a second thermochromic material capable of producing a second visible indication in the casting material when the casting material reaches or exceeds a second predetermined temperature at which the second thermochromic material undergoes a change in its color state. 
     
     
         25 . A method of determining whether a water-containing curing agent used to cure a moisture curable casting material is capable of causing a cast burn on a body member of a human or other animal subject when said casting material is applied to a human or other animal subject in need of said casting material, comprising the steps of: (a) immersing a temperature responsive orthopedic casting material comprising a curable casting matrix, a flexible substrate coated or impregnated with the curable casting matrix, and; a thermochromic material, into the water containing curing agent, (b) allowing the orthopedic casting material to hydrate with said curing water and; (c) applying the orthopedic casting material around the body member in need of casting; and (d) monitoring the casting material visually to determine if a predetermined temperature is indicated by a color change of the thermochromic material. 
     
     
         26 . The method according to  claim 25 , wherein the subject is human and the predetermined temperature is at or above 43° C. 
     
     
         27 . The method according to  claim 25 , wherein the curable casting matrix is selected from the group consisting of hexcelites, gypsum cements, isocyanate-functional prepolymers, alkoxysilane terminated prepolymers, polyurethane prepolymers, cyanoacrylate prepolymers, epoxy resins, thermoplastic resins, ethylene acrylic acid ester copolymers, ethyl vinyl acetate copolymers, and mixtures thereof. 
     
     
         28 . (canceled) 
     
     
         29 . The method according to  claim 26 , wherein the curable casting matrix comprises isocyanate functional prepolymer. 
     
     
         30 . The method according to  claim 26 , wherein the flexible substrate comprises fibers selected from the group consisting of acrylic fibers, fiberglass, polyester fibers, polypropylene fibers, polyaramide fibers, polyamide fibers, carbon fibers, glass fibers, multifilament fibers, polyethylene fibers, polyacrylonitrile copolymer fibers, cotton fibers, wool fibers, flax fibers, rayon fibers, and mixtures thereof. 
     
     
         31 . The method according to  claim 26 , wherein the flexible substrate comprises fiberglass. 
     
     
         32 . The method according to  claim 26 , wherein the casting material further comprises a non-thermochromic dye or pigment, or mixture thereof. 
     
     
         33 . The method according to  claim 28 , wherein the thermochromic material is selected from the group consisting of reversible or non-reversible thermochromic dyes, thermochromic pigments, thermochromic liquid crystals and mixtures thereof, which are capable of producing a visible indication in the casting material when the casting material reaches or exceeds a predetermined temperature at which the thermochromic material undergoes a change in its color state. 
     
     
         34 . The method according to  claim 26 , wherein the color change can be from a color to colorless, from one color to another color, or from colorless to a color. 
     
     
         35 . An orthopedic casting kit, comprising: (a) a flexible substrate coated or impregnated with a curable synthetic casting matrix; (b) a thermochromic material operable to exhibit a color change when the curable synthetic casting matrix reaches or exceeds a predetermined temperature; and (c) instructions comprising information which correlates the color change with the predetermined temperature. 
     
     
         36 . An orthopedic casting material comprising:
 (a) a curable synthetic casting matrix comprising a thermochromic material, and   (b) a flexible substrate coated or impregnated with the curable synthetic casting matrix.   
     
     
         37 . The orthopedic casting material according to  claim 36  wherein the curable casting matrix is a synthetic resin selected from the group consisting of hexcelites, isocyanate-functional prepolymers, alkoxysilane terminated prepolymers, polyurethane prepolymers, cyanoacrylate prepolymers, epoxy resins, thermoplastic resins, ethylene acrylic acid ester copolymers, ethyl vinyl acetate copolymers, and mixtures thereof. 
     
     
         38 . The orthopedic casting material according to  claim 37 , wherein the curable casting matrix comprises isocyanate functional prepolymer. 
     
     
         39 . The orthopedic casting material according to  claim 36 , wherein the thermochromic material is operative to change from one color to another color, from a color to colorless, or from colorless to a color, at the predetermined temperature. 
     
     
         40 . The orthopedic casting material according to  claim 39 , wherein the predetermined temperature is from about 40° C. to about 48° C.