Composite cellulose material and method for making such a material

Abstract

The present invention relates to a composite cellulose material, comprising: —a layer of a cellulose material, —a starch-based reinforcement grid which is positioned on at least one surface of the layer of cellulose material, the reinforcement grid comprising a plurality of meshes which are delimited by grid wires, the composite cellulose material having a relief in three dimensions comprising folds in the positioning zones of the reinforcement grid, and relief bumps on either side of the plane of the grid which are delimited by the folds.

1 . A composite cellulose material comprising:
 a layer of cellulose material,   a starch-based reinforcement grid positioned on at least one surface of the cellulose material layer, said reinforcement grid comprising a plurality of meshes delimited by grid wires,   the composite cellulose material having a three-dimensional relief comprising folds at the areas for positioning the reinforcement grid and raised bumps on either side of the plane of the grid delimited by the folds.   
     
     
         2 . The composite cellulose material according to  claim 1  wherein the three-dimensional relief has an overall thickness greater than the sum of the thicknesses of the layer of cellulose material and of the reinforcement grid. 
     
     
         3 . The composite cellulose material according to  claim 1 , wherein a coverage rate of the reinforcement grid on the at least one surface of the cellulose material layer is greater than or equal to 10%, preferably greater than or equal to 20%. 
     
     
         4 . The composite cellulose material according to  claim 1 , wherein a coverage rate of the reinforcement grid on the at least one surface of the cellulose material layer is less than or equal to 60%, preferably less than or equal to 50%. 
     
     
         5 . The composite cellulose material according to  claim 1 , wherein the grid wires form square or rectangular meshes. 
     
     
         6 . The composite cellulose material according to  claim 1 , wherein the grid wires form hexagonal meshes. 
     
     
         7 . The composite cellulose material according to  claim 6 , wherein the grid wires form honeycomb type meshes. 
     
     
         8 . The composite cellulose material according to  claim 6 , wherein the grid wires form bowtie type meshes. 
     
     
         9 . The composite cellulose material according to  claim 1 , wherein one or more grid wires are sinusoidal. 
     
     
         10 . The composite cellulose material according to  claim 1 , wherein the reinforcing grid is positioned on the cellulose material layer by screen printing, three-dimensional printing, intaglio, flexography, or spraying via one or more nozzles. 
     
     
         11 . The composite cellulose material according to  claim 1 , wherein the reinforcement grid is positioned on the at least one surface of the layer of cellulose material according to a quantity comprised between 2 g/m 2  and 50 g/m 2  after drying. 
     
     
         12 . The composite cellulose material according to  claim 1 , wherein the grid wires have a width in a plane of the grid comprised between 0.1 mm and 3 mm, preferably between 0.5 mm and 2.5 mm. 
     
     
         13 . The composite cellulose material according to  claim 1 , wherein a coverage rate of the reinforcement grid on the at least one surface of the cellulose material layer is comprised between 10% and 60%, preferably between 20% to 50%. 
     
     
         14 . A flexible package comprising a composite cellulose material according to  claim 1 . 
     
     
         15 . A wallpaper comprising a composite cellulose material according to  claim 1 . 
     
     
         16 . A notice board, preferably sandwich type, comprising a composite cellulose material according to  claim 1 . 
     
     
         17 . An envelope comprising a composite cellulose material according to  claim 1 . 
     
     
         18 . A method for manufacturing a composite cellulose material according to  claim 1  from a layer of cellulose material, comprising:
 depositing a starch-based reinforcement grid on at least one surface of the cellulose material, said reinforcement grid comprising a plurality of meshes delimited by grid wires, in order to form a three-dimensional relief comprising folds at the areas for positioning the reinforcement grid, and raised bumps on either side of the grid delimited by the folds. 
 
     
     
         19 . The manufacturing method according to  claim 18 , wherein the reinforcement grid deposited on the cellulose material comprises a starch suspension. 
     
     
         20 . The manufacturing method according to  claim 18 , wherein the grid is deposited by screen printing, three-dimensional printing, intaglio, flexography, or spraying via one or more nozzles. 
     
     
         21 . The manufacturing method according to  claim 18 , wherein a composition of the reinforcement grid comprises at least one starch suspension having a dry matter content comprised between 5% and 65% by weight when the reinforcement grid is deposited.