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. 13, 2009
Filed:
Mar. 17, 2005
Masaru Shinkai, Yokohama, JP;
Michiaki Shinotsuka, Hiratsuka, JP;
Hiroyuki Iwasa, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
The object of the present invention is to provide a multilayer phase-change information recording medium comprises a substrate, and N layers of information layer (N represents an integral number of 2 or more), and each of the information layers comprises at least a recording layer in which information is recorded by irradiating laser beam to induce a phase change between crystalline phase and amorphous phase. The present invention is characterized in that when the information layer is disposed so that a first information layer, a second information layer, a third information layer . . . , and N information layer are disposed in this sequence from the laser beam irradiation side, at least one information layer other than the N information layer comprises a lower protective layer, a recording layer, an upper protective layer, a reflective layer, and a thermal diffusion layer disposed in this sequence from the laser beam irradiation side; the thermal diffusion layer comprises at least indium (In) and oxygen (O) and further comprises any one of titanium (Ti) and zirconia (Zr); and the atomic ratio of indium (In) to all the metal elements in the thermal diffusion layer, In/all the metal elements, is 0.75 to 0.9.