发明授权
US4918683A Optical information medium having a base plate made of
polymethylmethacrylate which is a copolymer of methyl methacrylate and
methyl acrylate
失效
具有由聚甲基丙烯酸甲酯制成的基板的光学信息介质,其是甲基丙烯酸甲酯和丙烯酸甲酯的共聚物
- 专利标题: Optical information medium having a base plate made of polymethylmethacrylate which is a copolymer of methyl methacrylate and methyl acrylate
- 专利标题(中): 具有由聚甲基丙烯酸甲酯制成的基板的光学信息介质,其是甲基丙烯酸甲酯和丙烯酸甲酯的共聚物
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申请号: US178267申请日: 1988-04-06
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公开(公告)号: US4918683A公开(公告)日: 1990-04-17
- 发明人: Yoshie Kodera , Hisashi Kabe , Tetsu Ohishi , Jun Matsumoto
- 申请人: Yoshie Kodera , Hisashi Kabe , Tetsu Ohishi , Jun Matsumoto
- 申请人地址: JPX Tokyo
- 专利权人: Hitachi, Ltd.
- 当前专利权人: Hitachi, Ltd.
- 当前专利权人地址: JPX Tokyo
- 优先权: JPX61-236123 19861006
- 主分类号: B41M5/26
- IPC分类号: B41M5/26 ; C08F220/10 ; C08F220/14 ; G02B1/04 ; G11B7/24 ; G11B7/253
摘要:
An optical disc consists of a base plate, a reflective thin layer and a protective thin layer. As the base plate, polymethylmethacrylate is used. Since defects in the protective thin layer are a function of defects in the base plate, in order to reduce defects in the protective thin layer, defects in the base plate are reduced. For reducing defects in the base plate, a copolymer of methyl methacrylate and methyl acrylate is used.
公开/授权文献
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