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:
Aug. 07, 1979
Filed:
Dec. 01, 1977
Applicant:
Inventors:
John D Green, Romsey, GB;
Ian R Harris, Alton, GB;
Assignee:
British-American Tobacco Company Limited, London, GB;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
A24B / ; B01D / ;
U.S. Cl.
CPC ...
131 / ; 131 107 ; 131 109 ; 131265 ; 55 74 ;
Abstract
An improved tobacco-smoke filter or filter material contains granules of porous activated carbon to which has been applied a nitroxide of the group consisting of the nitroxide 4-oxo-2,2,6,6-tetramethylpiperidino-oxy, the nitroxide 1-nitronyl-3-oxyl-4,4,5,5-tetramethyl-2-phenyldihydroimidazole and mixtures thereof. The carbon may be loaded with 0.5 to 25%, suitably 1.0 to 15%, by weight of the nitroxide. Advantageously such a filter has provision for filter ventilation. For instance, in a triple filter with a center section containing the treated carbon, the said center section and/or the section upstream thereof is ventilated.