The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 18, 2005
Filed:
Mar. 25, 2003
Takeo Kojima, Kanagawa-Ken, JP;
Toyohito Asanuma, Yokohama, JP;
Takeo Kojima, Kanagawa-Ken, JP;
Toyohito Asanuma, Yokohama, JP;
Abstract
An optical disk includes a reflective layer, a recording layer, an optical-transparent bonding layer and an optical transparent sheet laminated on a substrate in this order. The total thickness of the optical-transparent bonding layer and the optical transparent sheet is 0.1 mm. The peak-to-peak height of wrinkles formed on the sheet is 2.5 μm or lower. The optical disk is produced as follows: A first ultraviolet ray is radiated to an optical transparent sheet at a first energy level in the range from 500 mJ/cmto 3000 mJ/cm, a wavelength of the first ultraviolet ray being in the range from 250 nm to 300 nm. Prepared next is a substrate laminated on which are a reflective layer and a recording layer in this order. Ultraviolet hardened resin is applied on the recording layer to form an optical-transparent bonding layer thereon. An optical transparent sheet is provided on the optical-transparent bonding layer. A second ultraviolet ray is radiated to the optical transparent sheet at a second energy level the same as or lower than the first energy level, to harden the optical-transparent bonding layer, thus the optical transparent sheet being bonded on the substrate via the optical-transparent bonding layer.