公开(公告)号：US5141973A

公开(公告)日：1992-08-25

申请号：US457942

申请日：1989-12-27

申请人： Tomokazu Kobayashi ,  Toshio Morihiro

发明人： Tomokazu Kobayashi ,  Toshio Morihiro

IPC分类号： A61B5/055 ,  B01J13/00 ,  C08J3/03 ,  G01R33/28 ,  G01R33/58

CPC分类号： C08J3/03 ,  G01R33/281 ,  G01R33/58 ,  C08J2329/04

摘要： A method of preparing a polyvinyl alcohol hydrogel contains the steps of charging an aqueous solution of a polyvinyl alcohol having a degree of hydrolysis of not less than 95 mol % and an average polymerization degree of not less than 500 into a container, the aqueous solution containing the polyvinyl alcohol in a concentration of not less than 5 wt. %, cooling the aqueous solution of the polyvinyl alcohol at a temperature of from - (minus) 9.degree. C. to - (minus) 3.degree. C., subjecting the aqueous solution of the polyvinyl alcohol to physical stimulation, and then maintaining the aqueous solution of the polyvinyl alcohol at a temperature of from - (minus) 5.degree. C. to + (plus) 5.degree. C. The polyvinyl alcohol hydrogel may be contained in a plastic container. An MRI phanton is composed of the plastic container containing such polyvinyl alcohol hydrogel.