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US 4,907,609 AGranted
Method of increasing the hardness of cigarette filter elements
AssigneeHercules Incorporated
InventorsRichmond R. Cohen, Jimmie D. McCarty
Life of this patent
Estimating the term…
Abstract
Filter element and method for increasing the hardness thereof by contacting filter plug material with effective amounts of (a) a water soluble resin (or copolymer) having available chelate bond-forming chemical groups and (b) a water soluble nontoxic salt, the metal cation of the nontoxic salt forming a chelate bond with the chelate bond-forming chemical groups of said water soluble resin.
Claims25
A method for increasing hardness of cigarette filter elements obtained from substrate in the form of at least one of an open fiber tow, a sliver, a ribbon of nonwoven material, and fibrillated film, comprising
- (A) contacting polyolefin-containing substrate with effective amounts of (a) a water soluble resin component having available chelate bond-forming chemical groups and (b) a nontoxic metal salt of an element selected from the group consisting of zinc, magnesium aluminum, sodium, calcium and potassium;
- said resin component forming a chelate bond with chelate bond-forming groups of said water soluble resin component;
- and
- (B) completing fabrication of the desired filter element.
1 more element
Dependencies are inferred from the claim text.