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:
May. 07, 1991
Filed:
Oct. 05, 1989
Hideki Matsuzawa, Odawara, JP;
Masao Yabe, Fujinomiya, JP;
Tadashi Irie, Odawara, JP;
Seiichi Watanabe, Odawara, JP;
Yusuke Ishihara, Odawara, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
Disclosed is an information storage medium having an air-sandwich structure which comprises two disc-shaped substrates joined together through a ring-shaped inner spacer and a ring-shaped outer spacer. These spacers are made of the same kind of resin as those forming the disc substrates and the resin of the spacers has a viscosity-average molecular weight larger than that of the resin of the substrates. Also disclosed is a process for producing the information storage medium by joining the spacers to the disc substrates by means of ultrasonic welding.