Title:
AN IMPROVED METHOD AND APPARATUS FOR MAKING DUAL-LAYER DVD DISCS
Document Type and Number:
WIPO Patent Application WO2001049482
Kind Code:
A3
Abstract:
An improved method and apparatus for making a dual-layer DVD disc that does not require a stamping step during its manufacture. A polycarbonate substrate (64) is molded and coated with a semireflective data layer (66). A PMMA substrate (60) having a diameter equal to that of the polycarbonate substrate (64) is molded and coated with a fully reflective data layer (62). Adhesive (68) is placed on the semireflective layer (66) and the fully reflective data layer (62) is transferred from its PMMA substrate (60) to the polycarbonate substrate (64) after the sandwiched substrate (60, 64) have been edge milled to remove any adhesive (68) that is transferred to the PMMA substrate (60). The polycarbonate substrate (64) thus ends up with two data layers (62, 66) in conformance with the DVD specifications and the PMMA substrate (60) can be recycled for later use.
Inventors:
VAN HOOF PETER
Application Number:
PCT/US2000/000107
Publication Date:
November 15, 2001
Filing Date:
January 25, 2000
Export Citation:
Assignee:
WARNER MUSIC GROUP INC (US)
International Classes:
B29C37/04; B29D17/00; G11B5/73; G11B5/84; G11B7/26; B29C65/48; (IPC1-7): B05D5/06; B32B3/02; B32B31/00; B41M3/12; B44C1/165; C23C14/00; G11B3/70; G11B7/24
Foreign References:
| US6117284A | 2000-09-12 | |||
| US4877475A | 1989-10-31 |
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