Acid depilation and extrudable fibril production from hide corium

Claim 1

IN THE METHOD OF PRODUCING A TUBULAR COLLAGEN CASING, THE STEPS OF: IMMERSIING FRESH UNDEHAIRED ANIMAL HIDE IN A DILUTE AQUEOUS SOLUTION OF AN ACID HAVING A DISSOCIATIONL CONSTANT IN AQUEOUS SOLUTION BETWEEN 1.0X10**5 AND 1.0X10**-3; SOAKING THE HIDE IN SAID ACID SOLUTION UNTIL THE EPIDERMAL LAYER AND THERMOSTAT LAYER OF SAID HIDE ARE SWOLLEN AND SOFTENED; REMOVING THE HIDE FROM THE ACID SOLUTION AND SCRAPING THE HIDE ON BOTH SIDES TO REMOVE FROM THE HIDE CORIUM ALL HAIR AND FLESH, THE HAIR FOLICLES, EPIDERMAL LAYER, DERMIS AND ADNEXIAL GLANDS WHICH CONSIST OF THE SEBACEOUS GLANDS AND THE SUDORIFIC GLANDS; TREATING THE DEHAIRED AND DEFLESHED HIDE CORIUM SO OBTAINED WITH A DILUTE AQUEOUS ALKALINE SOLUTION TO NEUTRALIZE RESIDUAL ACID PRESENT AND DESWELL THE CORIUM; WASHING THE CLEANED HIDE CORIUM WITH WATER; COMMINUTING THE CLEANED HIDE CORIUM AND RESWELLING THE COMMINUTED CORIUM IN ACID SOLUTION TO FORM A HOMOGENEOUS MASS OF SWOLLEN COLLAGEN FIBRILS HAVING A COLLAGEN SOLIDS CONTENT IN THE RANGE OF MORE THAN 2.5% AND LESS THAN 6% BY WEIGHT; EXTRUDING THE HOMOGENEOUS MASS OF SWOLLEN COLLAGEN FIBRILS TO FORM A CONTINUOUS, FRAGILE, TUBULAR BODY; APPLYING A COAGULANT TO SAID TUBULAR BODY; HARDENING THE COAGULATED BODY; WASHING COAGULANT FROM THE HARDENED BODY; MAINTAINING SUBSTANTIALLY THE SAME WALL THICKNESS IN SAID TUBULAR BODY THROUGHOUT THE AFORESAID STEPS OF COAGULATING, HARDENING AND WASHING SAID BODY; AND, DRYING SAID BODY, WHILE MAINTAINING THE INTERNAL DIAMETER OF SAID BODY SUBSTANTIALLY EQUAL TO THAT AT WHICH IT IS EXTRUDED.