Food container having enhanced biodegradability, heat-stability and absorbability

Abstract

A paper laminate provided for a food container includes a substrate paper or paper sheet, and at least a fibrous or fabric absorbent layer consisting of a biodegradable polymer selected from the group consisting of polylactic acid (PLA), polyhdroxyalkanoate (PHA), and polyhydroxy butyrate-co-valerate (PHBV), and a reinforcing polymer which includes a thermobondable polymer of polyethylene; with the absorbent layer formed, coated, bonded or adhered on the substrate paper to form a moisture and oil absorbable layer inside the food container to absorb moisture and oil in the food container for enhancing the food taste and quality, and also to provide a heat-durable and biodegradable food container.

1 . A food container made of a paper laminate comprising:
 a paper substrate made of paper, paper sheet or paper board; and   at least a fibrous absorbent layer formed on at least one surface of said paper substrate for absorbing moisture or oil as vaporized or released from a food as contacted with the surface of the food container and as stored in the food container;   said fibrous absorbent layer comprising a multi-component fiber including at least a biodegradable polymer and a reinforcing polymer.   
     
     
         2 . A food container according to  claim 1 , wherein said fibrous absorbent layer includes a non-woven fabric or woven fabric made from said multi-component fiber. 
     
     
         3 . A food container according to  claim 1 , wherein said biodegradable polymer is selected from the group consisting of: polylactic acid (PLA), polyhydroxyalkanoate (PHA), polyhydroxybutyrate-co-valerate (PHBV) and Copoly-L-Lactide (CPLA). 
     
     
         4 . A food container according to  claim 1 , wherein said reinforcing polymer includes a thermobondable polymer, which includes polyethylene (PE), and polypropylene (PP). 
     
     
         5 . A food container according to  claim 1 , wherein said fibrous absorbent layer is coated on said paper substrate by an adhesive or a binder. 
     
     
         6 . A food container according to  claim 5 , wherein said adhesive is a thermally bondable adhesive or a heat adhesive. 
     
     
         7 . A food container according to  claim 6 , wherein said adhesive includes polylactic acid and polyethylene. 
     
     
         8 . A food container according to  claim 1 , wherein said paper laminate further includes a protective film layer coated or formed on at least one side or one surface of said paper substrate. 
     
     
         9 . A food container according to  claim 8 , wherein said protective film layer includes a heat stable and biodegradable polymer. 
     
     
         10 . A food container according to  claim 9 , wherein said polymer includes polyethylene blended with polylactic acid. 
     
     
         11 . A food container according to  claim 1 , wherein said fibrous absorbent layer is further incorporated therein with a nano silver ingredient or an anti-bacterial ingredient. 
     
     
         12 . A food container according to  claim 1 , wherein said fibrous absorbent layer is further perforated to make it capillarily penetrable by oil and moisture. 
     
     
         13 . A food container made of a paper laminate comprising:
 a paper substrate; and   a protective film layer formed on at least one side or one surface of said paper substrate;   said protective film layer including a thermobondable polymer and a biodegradable polymer co-extruded or laminated to form said film layer.   
     
     
         14 . A food container according to  claim 13 , wherein said thermobondable polymer is polyethylene. 
     
     
         15 . A food container according to  claim 13 , wherein said biodegradable polymer is selected from the group consisting of: polylactic acid (PLA), polyhydroxy alkanoate (PHA), polyhydroxy butyrate-co-valerate (PHBV), and Copoly-L-Lactide (CPLA).