Open cell structure foamed cellulose acetate filters
AssigneeCelanese Corporation
InventorsCarl J. Howell, Jr., David W. Trott, Jesse L. Riley
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Abstract
This invention relates to a method of manufacturing foamed cellulose acetate and the product produced thereby. More specifically, the invention relates to a melt extrusion process for producing open cell structure foamed cellulose acetate having special use as a filtering element for an aerosol such as tobacco smoke.
Claims17
A cigarette filter rod comprising a substantially homogenously plasticized cellulose acetate, substantially open cell foam characterized by the presence of at least some cells which are bridged by fibrels, said cellulose acetate having a degree of esterification as expressed by acetyl value of about 55 percent, as combined acetic acid, and a bound sulfate content of less than 0.003 percent by weight.
A cigarette filter rod comprising a substantially homogenously plasticized cellulose acetate, substantially open cell foam characterized by the presence of at least some cells which are bridged by fibrils, said homogenously plasticized cellulose acetate employing a plasticizer selected from the group consisting of esters of saturated dibasic acids, esters of saturated polyhydric alcohols, fatty acid esters and sulfonamide resins.
Dependencies are inferred from the claim text.