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:
Jan. 05, 1999
Filed:
Sep. 22, 1995
Tanemi Asai, Ibo-gun, JP;
Syu Shimamoto, Himeji, JP;
Hiroyuki Matsumura, Himeji, JP;
Tohru Shibata, Himeji, JP;
Daicel Chemical Industries, Ltd., Osaka, JP;
Abstract
A tobacco filter material containing fibers which have a core and a surface layer which surrounds the core, wherein the core comprises a non-esterified cellulose and the surface layer comprises a cellulose ester. The fiber may be (A) a cellulose fiber coated with a cellulose ester or (B) a fibrous cellulose derivative with its surface layer esterified by an organic acid and having an average degree of substitution of not more than 1.5. Wood pulp can be used as the cellulose fiber and the amount of the cellulose ester in the coated cellulose (A) is 0.1% by weight or more. The cellulose derivative (B) has its surface layer esterified with an organic acid and retains a non-esterified core portion. This cellulose derivative may be obtained, for example, by the non-catalytic liquid phase treatment of a cellulose fiber with an organic acid and an organic acid anhydride or halide.