Medical appliance made of plastic

#This invention relates to a medical appliance made of polyvinyl chloride and, more particularly, to a medical appliance made of polyvinyl chloride suitable for use in direct or indirect contact with human blood, such as an artificial valve, artificial blood vessel, blood transfusion set, solution infusion set, or blood bag.

#Many of the above-noted medical appliances have heretofore been made of plastic materials which meet the non-toxicity requirements specified in the Japanese Pharmacopeia when tested according to the specified testing methods such as, for example, the testing method for plastic containers used in medical solution for infusion (solution infusion). In such plastic materials, polyvinyl chloride is widely used because it is inexpensive, is available in a broad range of stiffness from flexible to rigid depending on the plasticizer content to serve for various purposes, and, moreover, is transparent and easy-processing.

#Quite recently, however, it has been suggested that serious diseases might be caused if the human body takes in, through the blood contacted with a polyvinyl chloride plastics, phthalate esters including dioctyl phthalate which had long been believed to be a nontoxic plasticizer [for example J. Neergaard et al., Scand. J. Urol., Nephrol., 5, 141 (1971); R. J. Jaeger et al., New Eng. J. Med., 287 (22), 1,114 (1972); T. J. Contreras et al., Transfusion, 14, (1), 34 (1974); and Medical Stoff Conference, California Medicine, 112 (2), 43 (1970)].