Composite Materials for Food Contact Applications

Abstract

A composite material for food contact applications includes an absorbent layer and a non-absorbent layer, the absorbent layer having a textured surface for absorbing and trapping liquids, for example, oil, grease, or water, and the non-absorbent layer having an oleophobic surface that acts as an oil and grease specific liquid barrier. The material further includes one or more lamination layers. The lamination layer acts as a general liquid barrier between the absorbent layer and non-absorbent layer. This additional liquid barrier enhances the liquid repelling effect of the non-absorbent layer to more effectively trap liquids in the absorbent layer, thereby preventing liquids from seeping through the material onto an external surface.

We claim: 
     
         1 . A composite material comprising:
 a paper absorbent layer having a surface texture configured to absorb liquids from a food surface; and   a non-absorbent layer laminated to at least one surface of the absorbent layer, the non-absorbent layer having an oil and grease resistant material that forms a liquid barrier between the absorbent layer and the non-absorbent layer,   the material further is compostable and at least 90% bio-degradable within 84 days.   
     
     
         2 . The composite material of  claim 1 , wherein the material meets the 99% biodegradable composition requirement of the ASTM D6868-11 standard. 
     
     
         3 . The composite material of  claim 1 , wherein the material is fluorine free. 
     
     
         4 . The composite material of  claim 1 , wherein the material is non-biotoxic and safe for food contact applications. 
     
     
         5 . The composite material of  claim 1 , wherein the material has a flash point at or above 400° F. 
     
     
         6 . The composite material of  claim 1 , wherein the absorbent layer comprises one or many sheets of 5 lb to 55 lb basis weight paper. 
     
     
         7 . The composite material of  claim 1 , wherein the surface texture comprises a system of ridges and valleys, the ridges positioned on a surface of the absorbent layer to improve the absorbent layer's ability to absorb liquids from a food surface, the valleys are positioned on a surface of the absorbent layer to improve the absorbent layer's ability to trap liquids. 
     
     
         8 . The composite material of  claim 7 , wherein the absorbent layer absorbs at least 8.2 grams of fat from a large pizza after contacting the a pizza surface for at least 35 minutes. 
     
     
         9 . A composite material comprising:
 a paper absorbent layer having a surface texture configured to absorb liquids from a food surface;   a non-absorbent layer laminated to at least one surface of the absorbent layer, the non-absorbent layer having an oil and grease resistant material that forms a first liquid barrier between the absorbent layer and the non-absorbent layer; and   a lamination layer applied to at least one surface of the absorbent layer, the lamination layer joins the absorbent layer to the non-absorbent layer to create a second liquid barrier between the absorbent layer and the non-absorbent layer,   the material further is compostable and at least 90% bio-degradable within 84 days.   
     
     
         10 . The composite material of  claim 9 , wherein the liquid barrier formed by the non-absorbent layer comprises an oil and grease resistant paper material having at least 85% biobased content. 
     
     
         11 . The composite material of  claim 9 , wherein the absorbent layer further comprises at least one sheet of 5 lb to 55 lb basis weight paper, each sheet having a thickness ranging from 1.0 mils to 7.0 mils, a Sheffield porosity ranging from 150 units to 300 units, and a moisture percentage ranging from 5.0% to 7.5%. 
     
     
         12 . The composite material of  claim 9 , wherein the non-absorbent layer further comprises and oil and grease resistant material that includes at least one petroleum based polymer material. 
     
     
         13 . The composite material of  claim 12 , wherein the petroleum based polymer material in the non-absorbent layer is selected from the group consisting of high density polyethylene, low density polyethylene, linear low density polyethylene, ultra low density polyethylene, polyhydroxyalkanoate, polyglycolic acid, polyethylene terephthalate, polypropylene, polystyrene, polyvinyl chloride, and mixtures thereof. 
     
     
         14 . The composite material of  claim 9 , wherein the lamination layer comprises a water based polymer emulsion coating. 
     
     
         15 . The composite material of  claim 14 , wherein the lamination layer further comprises a binding agent that increases the lamination strength of the lamination layer, the binding agent increases the flash point of the composite to above 420° F. 
     
     
         16 . The composite material of  claim 9 , wherein the material meets the 99% biodegradable composition requirement of the ASTM D6868-11 standard. 
     
     
         17 . The composite material of  claim 9 , wherein the material is fluorine free, heavy metal free, non-biotoxic, safe for food contact applications, and has a flash point above 420° F. 
     
     
         18 . A composite material comprising:
 a absorbent layer having a biobased content of at least 90% and a surface texture configured to absorb liquids from a food surface, the surface texture having a system of valleys and ridges, the ridges positioned on a surface of the absorbent layer to provide a capillary force that wicks liquid from a food surface, the valleys are positioned on a surface of the absorbent layer to trap liquid in absorbent layer, the valleys are further positioned on a surface of the absorbent layer to draw absorbed liquid away from the ridges to increase the ridges capacity to absorb additional liquid from a food surface;   a non-absorbent layer laminated to at least one surface of the absorbent layer via a lamination layer, the non-absorbent layer having an oil and grease resistant material that forms a first liquid barrier between the absorbent layer and the non-absorbent layer, the first liquid barrier positioned between the absorbent layer and an external surface to prevent absorbed liquid trapped in the absorbent layer from seeping through non-absorbent layer and contacting the external surface; and   a lamination layer applied to at least one surface of the absorbent layer, the lamination layer joins the absorbent layer to the non-absorbent layer to create a second liquid barrier between the absorbent layer and the non-absorbent layer, the second liquid barrier compresses absorbed liquid into the space between the top surface of the ridges and the bottom surface of the valleys to prevent pooling of absorbed liquid in the absorbent layer and promote more even liquid absorption in the absorbent layer by driving absorbed liquid across the surface of the absorbent layer.   
     
     
         19 . The composite material of  claim 18 , where in the lamination layer bonds to the ridges on the surface of the absorbent layer to create a uniform surface for attaching the non-absorbent layer and form a seal over the space between the ridges and the valleys on the surface of the absorbent layer, the seal forms pockets for holding absorbed liquid in the space between the ridges and the valleys, the lamination layer traps absorbed liquid in the absorbent layer by compressing absorbed liquid into the pockets to draw absorbed liquid away from saturated portions of the absorbent layer to unsaturated portions. 
     
     
         20 . The composite material of  claim 19 , wherein the absorbent layer absorbs and traps at least 8.2 grams of fat from a large pizza after contacting the a pizza surface for at least 35 minutes.