Patent ID: 8241564

Claim:
A method for the manufacture of ultra high molecular weight polyethylene (UHMW) medical implants, where the implants have been made out of UHMW polyethylene formed by a method comprising: mixing a powder or granulate of UHMW polyethylene with an aqueous liquid that contains anthocyanin in a concentration of between about 0.002% and about 2.0% by weight; evaporating the aqueous liquid in order to deposit the anthocyanin in a predetermined concentration on the polyethylene particles; compressing the coated polyethylene particles into blocks or rods at temperatures in a range of approximately 135° C.-250° C. and pressures in a range of approximately 2-70 MPa and sequentially irradiating the blocks or rods at a dose of 2-5 MRads for a total dose of 9-12 MRads followed by heating below the melting point after each irradiation.