Disposable trays of fibre material coated with a removable film layer

Abstract

A method for producing a compression-moulded tray of fibre material, said tray being formed of fibre material in a compression method, from a suspension of mechanical pulp of cellulose. The formed tray is formed by press-drying using heat to a dry content of 80-95%, preferably 90-95%, and the fibre material of the formed tray has a density in the order of 400-650 kg/m3. The inside of the tray is provided with a protective barrier, said barrier being removable.

What is claimed is: 
     
         1 . A method of producing a fibre tray, comprising the steps of:
 a) forming a fibre tray by dewatering an aqueous suspension of cellulose from 1 to 15% in a forming section using a dewatering tray, the cellulose comprising at least 75% virgin fibre-based mechanical pulp, wherein the 75% virgin fibre-based mechanical pulp includes at least one of CMP (chemi-mechanical pulp), CTMP (chemithermomechanical pulp), cTMP (CTMP with a lower amount of added chemicals relative to CTMP), or HTCTMP (high temperature chemithermomechanical pulp);   b) press-drying the formed tray to a dry content of 80-95% and a density of 400-650 kg/m3;   c) coating the formed tray with a protective barrier; and   d) punching or reducing the thickness of a portion of said formed tray.   
     
     
         2 . The method according to  claim 1 , wherein said punching or reducing of the thickness of the formed tray is performed at an edge and/or rim portion of the tray. 
     
     
         3 . The method of  claim 1 , wherein said punching or reduction of the thickness of the formed tray is performed by punching or compressing said portion of the tray before or after coating with the protective barrier. 
     
     
         4 . The method of  claim 1 , wherein said press-drying is performed at 250-280° C. 
     
     
         5 . The method of  claim 1 , wherein said protective barrier is applied by coating a surface of the formed tray with a plastic emulsion that is polymerised to a film by the addition of an initiator, or dries to a film, on the formed tray. 
     
     
         6 . The method of  claim 1 , wherein said protective barrier is constituted by a film, wherein the film includes at least one of PET (polyethylene terepthalate), PA (polyamide), PP (polypropylene), PE (polyethylene), PBT (polybutylene terepthalate), or EVOH (ethylene vinyl alcohol copolymer). 
     
     
         7 . The method of  claim 1 , further comprising a step of heat laminating said protective barrier to the formed tray. 
     
     
         8 . The method of  claim 1 , wherein said protective barrier is removable from the formed tray by hand force. 
     
     
         9 . The method of  claim 1 , further comprising treating the fibre material of the formed tray with a hydrophobing agent. 
     
     
         10 . The method of  claim 9 , wherein the hydrophobing agent includes at least one of AKD (alkyl ketene dimer) and ASA (alkyl succinic anhydride). 
     
     
         11 . The method of  claim 1 , wherein the suspension of cellulose has a pH between 6 and 8.5.