Amorphous silica in packaging film

Abstract

An article of manufacture includes an oxygen scavenger and an amorphous silica. The article can be in the form of e.g. a film or sealing compound. A package can be made from the article for containing an oxygen-sensitive article such as food. The amorphous silica reduces migration of odor causing by-products of the oxygen scavenging process. A method of making an article of manufacture having reduced migration of by-products of an oxygen scavenging reaction includes providing an article including an oxygen scavenger and an amorphous silica; and exposing the article to actinic radiation.

What is claimed is:  
     
         1 . An article of manufacture comprising 
 a) an oxygen scavenger; and    b) an amorphous silica.    
     
     
         2 . The article of  claim 1  wherein the article comprises a film.  
     
     
         3 . The film of  claim 2  wherein the film comprises: 
 a) a layer comprising an oxygen scavenger; and  
 b) a layer comprising an amorphous silica.  
 
     
     
         4 . The film of  claim 2  wherein the film comprises a layer comprising an oxygen scavenger and an amorphous silica.  
     
     
         5 . The film of  claim 2  wherein the oxygen scavenger comprises a material selected from the group consisting of: 
 i) an oxidizable compound and a transition metal catalyst,  
 ii) an ethylenically unsaturated hydrocarbon and a transition metal catalyst,  
 iii) an ascorbate,  
 iv) an isoascorbate,  
 v) a sulfite,  
 vi) an ascorbate and a transition metal catalyst, the catalyst comprising a simple metal or salt, or a compound, complex or chelate of the transition metal,  
 vii) a transition metal complex or chelate of a polycarboxylic acid, salicylic acid, or polyamine,  
 viii) a reduced form of a quinone, a photoreducible dye, or a carbonyl compound which has absorbence in the UV spectrum, and  
 ix) a tannin.  
 
     
     
         6 . The film of  claim 2  wherein the amorphous silica has a mean pore diameter of between 20 and 200 Å.  
     
     
         7 . The film of  claim 2  wherein the amorphous silica comprises a synthetic amorphous silica.  
     
     
         8 . The film of  claim 2  further comprising an oxygen barrier layer.  
     
     
         9 . The film of  claim 2  further comprising an abuse resistant layer.  
     
     
         10 . The film of  claim 2  further comprising a heat sealable layer.  
     
     
         11 . The film of  claim 2  further comprising an intermediate adhesive layer disposed between any of the abuse-resistant layer and oxygen barrier layer, between the oxygen barrier layer and the layer comprising the oxygen scavenger, between the layer comprising the oxygen scavenger and the layer comprising the amorphous silica, and between the layer comprising the amorphous silica and the heat sealable layer.  
     
     
         12 . The film of  claim 2  wherein the film is cross-linked.  
     
     
         13 . The film of  claim 2  wherein the film is oriented.  
     
     
         14 . The film of  claim 2  wherein the film is heat shrinkable.  
     
     
         15 . The article of  claim 1  wherein the article is in the form of a sealing compound.  
     
     
         16 . The sealing compound of  claim 15  wherein the sealing compound is in the form of a gasket.  
     
     
         17 . The gasket of  claim 16  wherein the gasket comprises a polymer, an oxygen scavenger, and an amorphous silica.  
     
     
         18 . The gasket of  claim 16  wherein the gasket adheres a lid to a rigid or semi-rigid container.  
     
     
         19 . A package comprising: 
 a) an oxygen-sensitive article; and    b) a container into which the oxygen sensitive article is disposed, the container comprising an oxygen scavenger and an amorphous silica.    
     
     
         20 . A method of making an article of manufacture comprising: 
 a) providing an article comprising an oxygen scavenger and an amorphous silica; and    b) exposing the article to actinic radiation.