Method of producing ribbed board and product thereof

Abstract

A method for the production of ribbed board product, such as fiberboard, flakeboard, or waferboard, which resists fracturing during manufacture. The ribbed board product made according to the invention can be used as decking and in packaging and shipping components.

1 . A method of producing a ribbed board product, said method comprising the steps of: 
 a) forming a mat comprising a material selected from the group consisting of wood-based materials, agricultural fibers, and synthetic fibers;    b) providing the mat in a die, said die having a ribbed configuration with at least two outer zones and at least two angled zones;    c) closing the die to form a die gap, wherein the die gap at at least two of the outer zones differs from the die gap at at least two of the angled zones; and    d) consolidating said mat under pressure and heat to form the ribbed board product wherein the density of the ribbed board product differs in at least two locations.    
     
     
         2 . The method of  claim 1  wherein the die gap at the at least two outer zones during step (d) is about 0.090 inch to about 0.115 inch.  
     
     
         3 . The method of  claim 1  wherein the die gap at the at least two outer zones during step (d) is about 0.1 inch to about 0.115 inch.  
     
     
         4 . The method of  claim 1  wherein the die gap at the at least two angled zones during step (d) is about 0.115 inch to about 0.140 inch.  
     
     
         5 . The method of  claim 1  wherein the die gap at the at least two angled zones during step (d) is about 0.125 inch to about 0.130 inch.  
     
     
         6 . The method of  claim 1  wherein the product has a draft angle of from about 30 degrees to about 90 degrees.  
     
     
         7 . The method of  claim 1  wherein the material comprises wood fiber and step (d) comprises consolidating the mat to a board having an overall specific gravity of about 0.85 to about 1.10.  
     
     
         8 . The method of  claim 1  wherein the material comprises wood flakes and/or wafers and step (d) comprises consolidating the mat to a board having an overall specific gravity of about 0.65 to about 0.85.  
     
     
         9 . The method of  claim 1  wherein step (d) comprises consolidating the mat to a board having a specific gravity at the outer zones of about 0.75 to about 1.10.  
     
     
         10 . The method of  claim 1  wherein step (d) comprises consolidating the mat to a board having a specific gravity at the angled zones of about 0.65 to about 0.95.  
     
     
         11 . The method of  claim 1  wherein the material comprises wood flakes and/or wafers and step (d) comprises consolidating the mat to a board having a specific gravity at the outer zones of about 0.75 to about 0.85.  
     
     
         12 . The method of  claim 1  wherein the material comprises wood flakes and/or wafers and step (d) comprises consolidating the mat to a board having a specific gravity at the angled zones of about 0.65 to about 0.75.  
     
     
         13 . The method of  claim 1  wherein the ribbed board has a depth of draw of from about 0.125 inches to about 6.0 inches.  
     
     
         14 . The method of  claim 1  wherein the outer surfaces of the outer zones lie in a single plane.  
     
     
         15 . The method of  claim 1  further comprising consolidating the mat to produce a product having low density areas on the outer zones.  
     
     
         16 . A board product produced by the method recited in  claim 1 .  
     
     
         17 . A ribbed board product comprising: 
 at least two longitudinally extending outer zones having a first caliper;    at least one longitudinally extending angled zone having a second caliper, wherein said angled zone is disposed between and contiguous with said outer zones;    wherein said first caliper and said second caliper differ; and    wherein the density of the ribbed board product differs in at least two locations.    
     
     
         18 . The ribbed board product of  claim 17  wherein the ratio of the first caliper to the second caliper is less than about 0.9.  
     
     
         19 . The ribbed board of  claim 17  wherein said first caliper is about 0.090 inch to about 0.115 inch.  
     
     
         20 . The ribbed board of  claim 17  wherein said first caliper is about 0.1 inch to about 0.115 inch.  
     
     
         21 . The ribbed board of  claim 17  wherein said second caliper is about 0.115 inch to about 0.140 inch.  
     
     
         22 . The ribbed board of  claim 17  wherein said second caliper is about 0.125 inch to about 0.130 inch.  
     
     
         23 . The ribbed board of  claim 17  wherein the outer zones and angled zone form a draft angle in a range of about 30 degrees to about 90 degrees.  
     
     
         24 . The ribbed board of  claim 17  wherein the board comprises wood fiber and has an overall specific gravity of from about 0.85 to about 1.10.  
     
     
         25 . The ribbed board of  claim 17  wherein the board comprises wood flakes and/or wafers and has an overall specific gravity of from about 0.65 to about 0.85.  
     
     
         26 . The ribbed board of  claim 17  wherein the board has a specific gravity at the outer zones of about 0.75 to about 1.10.  
     
     
         27 . The ribbed board of  claim 17  wherein the board has a specific gravity at the angled zones of about 0.65 to about 0.95.  
     
     
         28 . The ribbed board of  claim 17  wherein the board comprises wood flakes and/or wafers and has a specific gravity at the outer zones of about 0.75 to about 0.85.  
     
     
         29 . The ribbed board of  claim 17  wherein the board comprises wood flakes and/or wafers and has a specific gravity at the angled zones of about 0.65 to about 0.75.  
     
     
         30 . The ribbed board of  claim 17  wherein the board has a depth of draw from about 0.125 inches to about 6.0 inches.  
     
     
         31 . The ribbed board of  claim 17  wherein the outer surfaces of the outer zones lie in a single plane.  
     
     
         32 . The ribbed board of  claim 17  wherein the board has low density areas on the outer zones.  
     
     
         33 . The ribbed board of  claim 32  wherein the low density areas on the outer zones extend upwardly from the outer zones and are about 0.06 inches to about 0.312 inches in diameter.  
     
     
         34 . A pallet comprising the ribbed board of  claim 17 .  
     
     
         35 . A method of producing a ribbed board product, said method comprising the steps of: 
 a) forming a mat comprising a material selected from the group consisting of wood-based materials, agricultural fibers, and synthetic fibers;    b) providing the mat in a die, said die having a ribbed configuration with at least two outer zones and at least two angled zones;    c) closing the die to form a die gap, wherein the die gap at at least two of the outer zones differs from the die gap at at least two of the angled zones; and    d) consolidating said mat under pressure and heat to form the ribbed board product wherein the density of the angled zones is less than the density of the outer zones.    
     
     
         36 . The method of  claim 35  wherein the material comprises wood fiber and step (d) comprises consolidating the mat to a board having an overall specific gravity of about 0.85 to about 1.10.  
     
     
         37 . The method of  claim 35  wherein the material comprises wood flakes and/or wafers and step (d) comprises consolidating the mat to a board having an overall specific gravity of about 0.65 to 0.85.  
     
     
         38 . The method of  claim 35  wherein step (d) comprises consolidating the mat to a board having a specific gravity at the outer zones of about 0.75 to 1.10.  
     
     
         39 . The method of  claim 35  wherein step (d) comprises consolidating the mat to a board having a specific gravity at the angled zones of about 0.65 to about 0.95.  
     
     
         40 . The method of  claim 35  wherein the material comprises wood flakes and/or wafers and step (d) comprises consolidating the mat to a board having a specific gravity at the outer zones of about 0.75 to about 0.85.  
     
     
         41 . The method of  claim 35  wherein the material comprises wood flakes and/or wafers and step (d) comprises consolidating the mat to a board having a specific gravity at the angled zones of about 0.65 to about 0.75.  
     
     
         42 . The method of  claim 35  wherein the ribbed board has a depth of draw of from about 0.125 inches to about 6.0 inches.  
     
     
         43 . A ribbed board product comprising: 
 at least two longitudinally extending outer zones having a first caliper;    at least one longitudinally extending angled zones having a second caliper, wherein said angled zone is disposed between and contiguous with said outer zones;    wherein the said first caliper and said second caliper differ; and wherein the density of the angled zones is less than the density of the outer zones.    
     
     
         44 . The ribbed board product of  claim 43  wherein the ratio of the first caliper to the second caliper is less than about 0.9.  
     
     
         45 . The ribbed board of  claim 43  wherein said first caliper is about 0.090 inch to about 0.115 inch.  
     
     
         46 . The ribbed board of  claim 43  wherein said first caliper is about 0.1 inch to about 0.115 inch.  
     
     
         47 . The ribbed board of  claim 43  wherein said second caliper is about 0.115 inch to about 0.140 inch.  
     
     
         48 . The ribbed board of  claim 43  wherein said second caliper is about 0.125 inch to about 0.130 inch.  
     
     
         49 . The ribbed board of  claim 43  wherein the outer zones and angled zone form a draft angle in a range of about 30 degrees to about 90 degrees.  
     
     
         50 . The ribbed board of  claim 43  wherein the board comprises wood fiber and has an overall specific gravity of from about 0.85 about 1.1.  
     
     
         51 . The ribbed board of  claim 43  wherein the board comprises wood flakes and/or wafers and has an overall specific gravity of from about 0.65 to about 0.85.  
     
     
         52 . The ribbed board of  claim 43  wherein the board has a specific gravity at the outer zones of about 0.75 to about 1.10.  
     
     
         53 . The ribbed board of  claim 43  wherein the board has a specific gravity at the angled zones of about 0.65 to about 0.95.  
     
     
         54 . The ribbed board of  claim 43  wherein the board comprises wood flakes and/or wafers and has a specific gravity at the outer zones of about 0.75 to about 0.85.  
     
     
         55 . The ribbed board of  claim 43  wherein the board comprises wood flakes and/or wafers and has a specific gravity at the angled zones of about 0.65 to about 0.75.  
     
     
         56 . The ribbed board of  claim 43  wherein the board has a depth of draw from about 0.125 inches to about 6.0 inches.  
     
     
         57 . The ribbed board of  claim 43  wherein the outer surfaces of the outer zones lie in a single plane.  
     
     
         58 . The ribbed board of  claim 43  wherein the board has low density areas on the outer zones.  
     
     
         59 . The ribbed board of  claim 58  wherein the low density areas on the outer zones extend upwardly from the outer zones and are about 0.06 inches to about 0.312 inches in diameter.