Abstract The present invention relates to a method of producing polyvinyl alcohol hydrogel characterized by the following features: the production process consists of a low-temperature processing stage in which the solution of polyvinyl alcohol with a polymerization degree over 1200 is processed at a low temperature so that polyvinyl alcohol is gelated, and a high-temperature processing stage in which the polyvinyl alcohol gelated in the low-temperature processing stage is dried, then processed at higher than 100°C; in this way, polyvinyl alcohol hydrogel with a saturated water content lower than 40 wt% is obtained. The hydrogels of this invention are useful for providing improved artificial articular cartilage for replacement of cartilage in the human body.
A method of producing polyvinyl alcohol hydrogel comprising (A) subjecting a solution of polyvinyl alcohol with a polymerization degree over 1200 to a temperature below -5°C so that the polyvinyl alcohol is gelated, (B) subjecting said hydrogel to high-temperature processing stage in which the polyvinyl alcohol gelated in the low-temperature processing stage is dried, (C) processing said hydrogel at higher than 100°C, whereby polyvinyl alcohol hydrogel with a saturated water content lower than 40 wt% is obtained.
Claim 2
Independent Claim
77 words
A method of producing polyvinyl alcohol hydrogel comprising (A) subjecting a solution of polyvinyl alcohol with a polymerization degree over 1200 to a temperature below -5°C so that the polyvinyl alcohol is gelated, (B) subjecting said hydrogel to high-temperature processing stage in which the polyvinyl alcohol gelated in the low-temperature processing stage is dried, (C) processing said hydrogel at higher than 100°C, whereby polyvinyl alcohol hydrogel with a saturated water content lower than 40 wt% is obtained.
Claim 3
Independent Claim
76 words
A method for preparing an artificial articular cartilage formed of polyvinyl alcohol hydrogel for biological implantation comprising (A) subjecting a solution of polyvinyl alcohol with a polymerization degree over 1200 to a temperature below -5°C so that the polyvinyl alcohol is gelated, (B) drying said hydrogel, (C) subjecting said hydrogel to a high-temperature processing step at a temperature higher than 100°C, whereby polyvinyl alcohol hydrogel with a saturated water content lower than 40 wt% is obtained.
Claim 4
Independent Claim
76 words
A method for preparing an artificial articular cartilage formed of polyvinyl alcohol hydrogel for biological implantation comprising (A) subjecting a solution of polyvinyl alcohol with a polymerization degree over 1200 to a temperature below -5°C so that the polyvinyl alcohol is gelated, (B) drying said hydrogel, (C) subjecting said hydrogel to a high-temperature processing step at a temperature higher than 100°C, whereby polyvinyl alcohol hydrogel with a saturated water content lower than 40 wt% is obtained.
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