公开(公告)号：EP0858070A4

公开(公告)日：2004-04-14

申请号：EP97935862

申请日：1997-08-22

申请人： SONY CORP ,  NIPPON ZEON CO

发明人： OYANAGI EIKI ,  SASA TAKESHI ,  IMAI YASUYUKI ,  TAKINO HIROSHI ,  KOHARA TEIJI ,  OSHIMA MASAYOSHI

IPC分类号： B29C70/64 ,  C08F32/04 ,  G11B5/596 ,  G11B5/60 ,  G11B5/73 ,  G11B5/82 ,  G11B5/84 ,  G11B21/21 ,  G11B23/00 ,  G11B5/64

CPC分类号： G11B23/0021 ,  B29C70/64 ,  C08F32/04 ,  G11B5/59633 ,  G11B5/6011 ,  G11B5/7315 ,  G11B5/82 ,  G11B5/8404 ,  G11B21/21 ,  Y10S428/913 ,  Y10T428/21

摘要： A disc medium substrate which is made of resin and used for a disc, for instance a magnetic disc, on/from which information is recorded/reproduced with a floating head. Protrusions higher than 50 nm are not formed on the surface of the substrate which is scanned by the floating head. The substrate is so molded that the number of particles in the molding material whose particle diameters are larger than 5 mu m is not more than 10000/g. The molding can be injection molding. Thermoplastic norvolnene system resin can be employed as the molding material. Projections and recesses corresponding to recording tracks may be provided on the substrate.

公开(公告)号：EP0844058A4

公开(公告)日：1998-12-09

申请号：EP97918402

申请日：1997-05-09

申请人： SONY CORP

发明人： SASA TAKESHI ,  TAKEGAWA TOSHIHIKO ,  OYANAGI EIKI ,  ISHIDA TAKEHISA

IPC分类号： B29C45/26 ,  G11B5/84 ,  G11B7/24 ,  G11B7/26 ,  G11B23/00 ,  B29C33/38 ,  G11B5/82

CPC分类号： G11B7/261 ,  B29C45/263 ,  G11B5/8404 ,  G11B7/24 ,  G11B7/263 ,  G11B23/0057 ,  Y10S425/81 ,  Y10S428/90 ,  Y10T428/24355

摘要： Synthetic resin material is molded with a mold to produce the disc substrate of an information signal recording medium. The molding part of the mold in which the disc substrate is molded is composed of a first mold which is a fixed mold and a second mold which is a movable mold. Both the mold is butted against each other. Metal smoothing layers are formed integrally on the molding surface sides of the first and second molds. Further, uneven patterns which correspond to information signals, etc. recorded on the disc substrate are directly formed on the metal layers. Thus, the disc substrate whose surface is flattened with a high precision and is free from local undulations and protrusions and onto which the uneven patterns on the mold sides are transferred with a high precision can be obtained.