Method of molding optical recording drums
US5342682A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 1991 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Oct 24, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2998
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for fabricating in a mold a rotatable recording drum is disclosed. Initially, the mold is rotated and a predetermined quantity of a flowable substance is poured into the mold cavity and is centrifugally flung against the mold wall to form a mold layer with a smooth inner surface. Next, a surface substance is poured into the mold cavity and is allowed to harden against the mold layer. A core outer layer substance is then poured into the mold cavity and allowed to harden against the surface substance, and rotation of the mold is stopped. The mold layer fluid is removed, and the cavity inside the outer layer is filled with a core inner layer substance which is allowed to harden before the drum core is removed from the mold cavity. Following removal of the core from the mold cavity, the hardened surface substance may be vacuum coated, and a protective overcoat applied to the core. The drum core and the surface substance can also be formed separately.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.