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EP0365108A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Low water content polyvinyl alcohol hydrogel and artificial cartilage

Assignee: Mizu Systems Inc
•
Filing: 1989-04-25
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Granted: —
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Expires: 2009-04-25
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Abstract

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.

Inventors

  • 👤 Yoshito Ikada
  • 👤 Shokyu Gen

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-22 23:56
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/03; A; A61; A61L; A61L27/00; A61L27/14; A61L27/16; C08J3/09; C08J2329/00; C08J2329/02; C08J2329/04

Claims Analysis

Total Claims: 4
Claim 1
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 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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