Oxygen scavenging compositions from concentrates
AssigneeW. R. Grace & Co.-Conn.
InventorsBruce D. Zenner, Charles S. Benedict
Life of this patent
Estimating the term…
Loading patent…
AssigneeW. R. Grace & Co.-Conn.
InventorsBruce D. Zenner, Charles S. Benedict
Estimating the term…
An oxygen scavenging composition or concentrate of a carrier, such as a polymer, which is permeable to both oxygen and water or water vapor and an oxygen scavenging compound of an organic compound or salt thereof dispersed relatively uniformly throughout the polymer in an amount effective to act as an oxygen scavenger. The oxygen scavenging compound may be an ascorbate compound or a polycarboxylic or salicylic acid chelate or complex of a transition metal or a salt thereof. The oxygen scavenging composition is activated for scavenging oxygen by contact with water or water vapor which permeates into or through the carrier. A catalyzing agent is included in an amount sufficient to increase the rate of oxygen scavenging by the ascorbate compound. The oxygen scavenging compound may be added to the composition in a dry state, and is inactive until activated by contact with water or water vapor.
A method for forming an oxygen scavenging composition, the method comprising mixing a first concentrate with a second concentrate, wherein the first concentrate includes an ascorbate as an oxygen scavenging material dispersed throughout the first concentrate in a concentration of between about 10 and 50% by weight and is activated by water or water vapor, and a first polymeric carrier which is substantially free of catalyzing agents and is permeable to water and/or water vapor, and wherein the second concentrate includes a catalyzing agent dispersed throughout the second concentrate in a concentration of between about 0.3 and 8% by weight, and a second polymeric carrier which is substantially free of the oxygen scavenging material and is permeable to water and/or water vapor.
Dependencies are inferred from the claim text.