Multi-layer composite pulp product, and system and process for manufacturing same

Abstract

Exemplary embodiments of a multi-layer composite pulp product comprise one or more pulp layers, and one or more reinforcement layers disposed therebetween. Each of these layers preferably include a respective pattern of opposingly-defined cavities and protrusions, wherein the mutual disposition of the layers results in their patterns axially aligning with one another. The reinforcement layers may be comprised of a recycled plastic, a metallic mesh or a metallic sheet. One example process for manufacturing a multi-layer composite pulp product may comprise fabricating a reinforcement layer, forming a soggy first pulp layer, placing a reinforcement layer on the soggy first pulp layer, forming a soggy second pulp layer, and positioning the soggy second pulp layer on the reinforcement layer. A precursor wet composite may thereby be formed, and may be dried at a selected heating temperature and under a selected pressure.

1 . A multi-layer composite pulp product comprising:
 a first pulp layer;   a second pulp layer; and   a reinforcement layer disposed between the first pulp layer and the second pulp layer.   
     
     
         2 . The multi-layer composite pulp product of  claim 1 , wherein
 (a) the first pulp layer has a first pattern of opposingly-defined cavities and protrusions;   (b) the second pulp layer has a second pattern of opposingly-defined cavities and protrusions;   (c) the reinforcement layer has a reinforcement pattern of opposingly-defined cavities and protrusions; and   (d) the reinforcement pattern is aligned with the first pattern and the second pattern.   
     
     
         3 . The multi-layer composite pulp product of  claim 2 , wherein
 (a) the product extends in generally planar fashion radially of a main axis; and   (b) the alignment is in a direction parallel to the main axis.   
     
     
         4 . The multi-layer composite pulp product of  claim 2 , wherein
 (a) the first pulp layer has a uniform wall thickness;   (b) the second pulp layer has a uniform wall thickness; and   (c) the reinforcement layer has a uniform wall thickness.   
     
     
         5 . The multi-layer composite pulp product of  claim 4 , wherein the uniform wall thickness of the reinforcement layer is different from the uniform wall thickness of both the first pulp layer and the second pulp layer. 
     
     
         6 . The multi-layer composite pulp product of  claim 5 , wherein the uniform wall thicknesses of the first pulp layer and the second pulp layer are the same. 
     
     
         7 . The multi-layer composite pulp product of  claim 1 , wherein the reinforcement layer is comprised of a plastic. 
     
     
         8 . The multi-layer composite pulp product of  claim 1 , wherein the reinforcement layer is comprised of a metallic mesh. 
     
     
         9 . The multi-layer composite pulp product of  claim 1 , wherein the reinforcement layer is comprised of a metallic sheet. 
     
     
         10 . The multi-layer composite pulp product of  claim 1 , wherein the reinforcement layer is comprised of material selected from the group consisting of plastic, metallic mesh and metallic sheet. 
     
     
         11 . The multi-layer composite pulp product of  claim 10 , wherein the first pulp layer and the second pulp layer comprise alkyl ketene dimer (AKD) sizing agent. 
     
     
         12 . A process for manufacturing a multi-layer composite pulp product, the process comprising:
 fabricating a reinforcement layer;   forming a soggy first pulp layer;   placing the reinforcement layer on the soggy first pulp layer;   forming a soggy second pulp layer;   positioning the soggy second pulp layer on the reinforcement layer, wherein a precursor wet composite is defined by the soggy first pulp layer, the reinforcement layer, and the soggy second pulp layer being in a stacked configuration; and   drying the precursor wet composite at a selected heating temperature and under a selected pressure.   
     
     
         13 . The process of  claim 12 , wherein
 the fabricated reinforcement layer has a reinforcement pattern of opposingly-defined cavities and protrusions;   the formed soggy first pulp layer has a first pattern of opposingly-defined cavities and protrusions;   the formed soggy second pulp layer has a second pattern of opposingly-defined cavities and protrusions; and   in the stacked configuration, the reinforcement pattern is aligned with the first pattern and the second pattern.   
     
     
         14 . The process of  claim 13 , wherein each of the steps of forming are
 by way of applying a quantity of fluid pulp to a forming mold; and   dehydrating the quantity of fluid pulp thereat for a set dehydration time.   
     
     
         15 . The process of  claim 13 , further comprising:
 prior to the step of placing, transferring the soggy first pulp layer onto a lower hot press mold by way of transfer mold;   the step of positioning is by way of transfer mold; and   the step of drying involves compression of the precursor wet composite between the lower hot press mold and an upper hot press mold.   
     
     
         16 . The process of  claim 15 , further comprising:
 after the step of drying, separating the upper hot press mold and lower hot press mold, and removing the multi-layer composite pulp product therefrom.   
     
     
         17 . The process of  claim 16 , wherein the reinforcement layer is comprised of material selected from the group consisting of plastic, metallic mesh and metallic sheet. 
     
     
         18 . The process of  claim 17 , wherein the soggy first pulp layer and the soggy second pulp layer comprise alkyl ketene dimer (AKD) sizing agent. 
     
     
         19 . The process of  claim 12 , wherein
 the reinforcement layer is comprised of recycled plastic, and   the step of fabricating includes injection molding.   
     
     
         20 . The process of  claim 12 , wherein
 the reinforcement layer is comprised of sheet metal or metallic mesh, and   the step of fabricating includes a pressing or stamping operation.   
     
     
         21 . The process of  claim 12 , wherein the heating temperature is from 150 to 260 degrees Celsius. 
     
     
         22 . The process of  claim 12 , wherein the selected pressure is 19-29 PSI. 
     
     
         23 . The process of  claim 12 ,
 wherein the fluid pulp has a pulp concentration of 1.5% to 4% pulp.   
     
     
         24 . A multi-layer composite pulp product comprising:
 a pulp layer having a lower face, an upper face disposed oppositely of the lower face, and a core pattern of opposingly-defined cavities and protrusions; and   an upper reinforcement layer comprised of molded plastic sheet and having an upper reinforcement pattern of opposingly-defined cavities and protrusions;   wherein the upper reinforcement layer is affixed to the upper face with the upper reinforcement pattern being aligned with the core pattern.   
     
     
         25 . The multi-layer composite pulp product of  claim 24 , wherein
 the product further comprises a lower reinforcement layer comprised of molded plastic sheet and having a lower reinforcement pattern of opposingly-defined cavities and protrusions; and   the lower reinforcement layer is affixed to the lower face with the lower reinforcement pattern being aligned with the core pattern.   
     
     
         26 . The multi-layer composite pulp product of  claim 25 , wherein
 (a) the product extends in generally planar fashion radially of a main axis; and   (b) the alignments are in a direction parallel to the main axis.   
     
     
         27 . The multi-layer composite pulp product of  claim 25 , wherein
 (a) the pulp layer has a uniform wall thickness;   (b) the lower reinforcement layer has a uniform wall thickness;   (c) the upper reinforcement layer has a uniform wall thickness; and   (d) the uniform wall thicknesses of the reinforcement layers are different from the uniform wall thickness of the pulp layer.   
     
     
         28 . The multi-layer composite pulp product of  claim 24 , wherein the reinforcement layers are comprised of a recycled plastic. 
     
     
         29 . A process for manufacturing a multi-layer composite pulp product, the process comprising:
 obtaining a first plastic sheet and a second plastic sheet, the first and second plastic sheets being comprised of a recycled plastic;   fabricating a lower reinforcement layer from the first plastic sheet, the lower reinforcement layer having a lower reinforcement pattern of opposingly-defined cavities and protrusions;   fabricating an upper reinforcement layer from the second plastic sheet, the upper reinforcement layer having an upper reinforcement pattern of opposingly-defined cavities and protrusions;   forming a pulp layer having a core pattern of opposingly-defined cavities and protrusions;   positioning the pulp layer on the lower reinforcement layer;   placing the upper reinforcement layer on the pulp layer; and   pressing the upper reinforcement layer, the pulp layer and the lower reinforcement layer together with the lower and upper reinforcement patterns being aligned with the core pattern;   wherein the step of pressing is at a first selected heating temperature and under a first selected pressure.   
     
     
         30 . The process of  claim 29 , further comprising:
 after the step of positioning the pulp layer on the lower reinforcement layer, compressing the pulp layer and lower reinforcement layer together;   wherein the step of compressing is at a second selected heating temperature and under a second selected pressure.   
     
     
         31 . The process of  claim 30 , wherein the heating temperatures are from 150 to 260 degrees Celsius. 
     
     
         32 . The process of  claim 30 , wherein the selected pressures are 19-29 PSI. 
     
     
         33 . The process of  claim 31 , wherein the first selected heating temperature is different from the second selected heating temperature. 
     
     
         34 . The process of  claim 31 , wherein the first selected pressure is different from the second selected pressure.