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:
Dec. 13, 1977
Filed:
Jun. 19, 1975
Robin Arthur Crellin, Romsey, EN;
Christopher Robert Jenkins, Southampton, EN;
James William Phelpstead, Southampton, EN;
Brown & Williamson Tobacco Corporation, Louisville, KY (US);
Abstract
According to the invention, a material for the filtration of tobacco smoke by reduction of vapor-phase constituents without adverse effect on the taste of the smoke comprises carbon particles of a size substantially within the range of 300 to 1700 micron, coated over their surfaces, individually and without being bonded together, with a barrier layer which has a thickness within the range of 5 .times. 10.sup.-4 to 0.5 micron and which is discontinuous in that it has a porosity within the range of 7,000 to 200,000 cm.sup.3 /min/10 cm.sup.2 per 10 cm water gauge and a permeability for organic vapors contained in tobacco smoke such that it permits the passage of molecules within the size range 5 .times. 10.sup.-4 to 2 micron, the said layer being composed substantially of an organic non-nitrogen-containing polymeric material which is non-volatile, substantially non-water-soluble and non-toxic. The invention is further concerned with tobacco smoke filters comprising such coated carbon particles.