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. 01, 2013
Filed:
Dec. 08, 2009
Takeshi Suzuki, Fujioka, JP;
Atsunori Satake, Fujioka, JP;
Noboru Kanba, Fujioka, JP;
Akihito Mitsui, Yokohama, JP;
Yoshihisa Suda, Tokyo, JP;
Takeshi Suzuki, Fujioka, JP;
Atsunori Satake, Fujioka, JP;
Noboru Kanba, Fujioka, JP;
Akihito Mitsui, Yokohama, JP;
Yoshihisa Suda, Tokyo, JP;
Mitsubishi Pencil Company, Limited, Tokyo, JP;
Abstract
A carbonaceous acoustic diaphragm whose density is reduced while retaining the required stiffness is provided. Carbon nanofibers and spherical particles of PMMA are mixed into a carbon-containing resin such as a polyvinyl chloride resin, and the mixture is carbonized to vaporize the spherical particles of PMMA, thereby forming a porous structure having pores with the carbon nanofibers in a powdered form uniformly dispersed through amorphous carbon. By forming a multilayer structure by combining the porous layer with a layer that does not use PMMA, the density can be further reduced while retaining the stiffness.