Composite boards comprising cellulosic plant material

Abstract

There is described a composite board comprising: iv) cellulosic plant material; v) a hydrophilic substance; and vi) an adhesive or resin. There is described a method of making a composite board comprising the steps of: i) providing particulate cellulosic plant material; ii) treating the cellulosic plant material with a hydrophilic substance; iii) adding an adhesive or resin to the cellulosic plant material treated with the hydrophilic substance iv) forming a board with the mixture formed in step iii); and v) drying the board.

1 . A composite board comprising:
 i) cellulosic plant material;   ii) a hydrophilic substance in the form of ascorbic acid and/or vitamin C; and   iii) an adhesive or resin.   
     
     
         2 . The composite board according to  claim 1  which is a particle board or fibre board. 
     
     
         3 . The composite board according to  claim 1  wherein the cellulosic plant material comprises cellulosic material derived from a woody plant, cellulosic material derived from recovered or recycled wood, non-wood cellulosic material or mixtures thereof. 
     
     
         4 . The composite board according to  claim 3  wherein the cellulosic plant material comprises material derived from a woody plant. 
     
     
         5 . The composite board according to  claim 3  wherein the cellulosic plant material comprises non-wood cellulosic plant material. 
     
     
         6 . The composite board according to  claim 5  wherein the non-wood cellulosic plant material is selected from corn stover, rice straw, wheat straw, barley straw, oat straw, rape seed straw, switch grass, siteria grass, flax, yukka fibre, lemongrass, jute, sisal, bamboo, pine needles, lupins, kenaf, coir fibre, coconut husks, cotton stalks, coffee husks, ground nut husks, areca nut husks, casaurina leaves, banana leaves and banana stem. 
     
     
         7 . The composite board according to  claim 1  wherein the hydrophilic substance is selected from polyhydroxy compounds, polycarboxylic acids, hydroxycarboxylic acids, amino acids and hydroxyamino compounds. 
     
     
         8 . The composite board according to  claim 7  wherein the hydrophilic substance is selected from ascorbic acid. 
     
     
         9 . The composite board according to  claim 8  wherein the carbohydrate is selected from glyceraldehyde, erythrose, threose, ribose, arabinose, xylose, lyxose, allose, allose, glucose, mannose, gulose, idose, galactose, talose, sucrose, maltose, lactose, fructose and mixtures thereof. 
     
     
         10 . The composite board according to  claim 8  wherein the hydrophilic substance is ascorbic acid in the form of vitamin C. 
     
     
         11 . The composite board according to  claim 1  wherein the adhesive or resin is selected from a polyvinylacetate resin, a formaldehyde resin, a urea melamine resin, a melamine formaldehyde resin, a phenol formaldehyde resin, a phenol melamine formaldehyde resin, a melamine resin, a urea formaldehyde resin, a melamine urea formaldehyde resin, a melamine urea phenolic formaldehyde resin, a methylene diphenyl diisocyanate resin, a polymethylene diphenyl diisocyanate resin or a combination thereof. 
     
     
         12 . The composite board according to  claim 11  wherein the adhesive or resin is selected from a melamine urea formaldehyde resin and a polymethylene diphenyl diisocyanate resin. 
     
     
         13 . A method of making a composite board comprising the steps of:
 i) providing particulate cellulosic plant material;   ii) treating the cellulosic plant material with a hydrophilic substance;   iii) optionally adding an adhesive or resin to the cellulosic plant material treated with the hydrophilic substance   iv) forming a board with the mixture formed in step iii); and   v) drying the board.   
     
     
         14 . The method of making a composite board according to  claim 13  wherein the composite board is selected from a particle board and a fibre board. 
     
     
         15 . The method according to  claim 13  wherein the cellulosic plant material comprises cellulosic material derived from a woody plant, cellulosic material derived from recovered or recycled wood, non-wood cellulosic material or mixtures thereof. 
     
     
         16 . The method according to  claim 13  wherein the cellulosic plant material comprises material derived from a woody plant. 
     
     
         17 . The method according to  claim 13 , wherein the particulate cellulosic plant material has an average particle size in the range of 5 to 200 mm in length. 
     
     
         18 . The method according to  claim 13  wherein the hydrophilic substance is added in an amount of 3 to 7% by weight of the cellulosic plant material. 
     
     
         19 . The method according to  claim 13 , wherein the resin is a melamine urea formaldehyde resin. 
     
     
         20 - 27 . (canceled) 
     
     
         28 . The method according to  claim 13  wherein the resin is a polymethylene diphenyl diisocyanate resin. 
     
     
         29 . The method according to  claim 13  wherein the resin or adhesive is added in an amount of between 1 and 40% by weight of the cellulosic plant material. 
     
     
         30 . The method according to  claim 13  wherein the melamine urea formaldehyde resin is added in an amount of 10 to 20% by weight of the cellulosic plant material. 
     
     
         31 . The method according to  claim 13  wherein the polymethylene diphenyl diisocyanate resin is added in an amount of 1 to 10% by weight of the cellulosic plant material.