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.

Claims

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.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Further advantages of the present invention may become apparent to those skilled in the art with the benefit of the following detailed description of the preferred embodiments and upon reference to the accompanying drawings in which:

[0009] FIG. 1 is a diagrammatic perspective view of one non-limiting example of a multi-layer composite pulp product, in the form of a pallet;

[0010] FIG. 2 is a further diagrammatic perspective view of the example multi-layer composite pulp product of FIG. 1;

[0011] FIG. 3 is a diagrammatic top view of the example multi-layer composite pulp product of FIG. 1;

[0012] FIG. 4 is a diagrammatic cross-sectional view taken along lines 4-4 of FIG. 3;

[0013] FIG. 5 is a magnified view of detail 5 in FIG. 4;

[0014] FIG. 6 is a diagrammatic exploded cross-sectional view of the example multi-layer composite pulp product of FIG. 1, taken along lines 4-4 of FIG. 3;

[0015] FIG. 7 is a diagrammatic view of one non-limiting system for manufacturing a multi-layer composite pulp product, shown prior to implementation of the system;

[0016] FIG. 8 is a diagrammatic view of the manufacturing system of FIG. 7, but wherein an example reinforcement layer fabrication subsystem is shown fabricating an example reinforcement layer, and a quantity of fluid pulp is shown applied to an example forming mold;

[0017] FIG. 9 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 8, wherein the reinforcement layer has now been removed from the fabrication subsystem, and a formed soggy first pulp layer now resides on the forming mold ready for transfer;

[0018] FIG. 10 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 9, wherein the transfer mold has now received the formed soggy first pulp layer from the forming mold;

[0019] FIG. 11 is a diagrammatic view of the manufacturing system of FIG. 7, but showing steps subsequent to those shown in FIG. 10, wherein the transfer mold and the lower hot press mold have moved into alignment with one another;

[0020] FIG. 12 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 11, wherein the soggy first pulp layer has now been released from the transfer mold and onto the lower hot press mold;

[0021] FIG. 13 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 12, wherein the reinforcement layer is being placed onto the soggy first pulp layer residing on the lower hot press mold, and the transfer mold has returned to alignment with the forming mold;

[0022] FIG. 14 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 13, wherein the transfer mold has now received a formed soggy second pulp layer from the forming mold;

[0023] FIG. 15 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 14, wherein the transfer mold with the soggy second pulp layer has returned into alignment with the lower hot press mold;

[0024] FIG. 16 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 15, wherein the soggy second pulp layer has now been released from the transfer mold and positioned onto the reinforcement layer, thereby completing formation of an example wet precursor composite;

[0025] FIG. 17 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 16, wherein the lower hot press mold with the wet precursor composite has now moved into alignment with a corresponding upper hot press mold;

[0026] FIG. 18 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 17, wherein the precursor wet composite is now being dried under compression between the upper and lower hot press molds;

[0027] FIG. 19 is a diagrammatic view of the manufacturing system of FIG. 7, but showing manufacturing steps subsequent to those shown in FIG. 18, wherein the multi-layer composite pulp product is now released (e.g., ejected) from the upper and lower hot press molds;

[0028] FIG. 20 is a diagrammatic side view of an example multi-layer composite pulp product in the form of a pallet, wherein the pallet is shown supporting a load above a local substrate

[0029] FIG. 21 is a diagrammatic top view of a second non-limiting example of a multi-layer composite pulp product in the form of a pallet;

[0030] FIG. 22 is a diagrammatic cross-sectional view taken along lines 22-22 of FIG. 21;

[0031] FIG. 23 is a diagrammatic magnified view of detail 23 in FIG. 22;

[0032] FIG. 24 is a diagrammatic exploded cross-sectional view of the example multi-layer composite pulp product of FIG. 21, taken along lines 22-22 of FIG. 21;

[0033] FIG. 25 is a diagrammatic view of one non-limiting example of a step of fabricating a reinforcement layer from a plastic sheet, for example by way of vacuum forming or stamping operation;

[0034] FIG. 26 is a diagrammatic view of a second non-limiting system for manufacturing a multi-layer composite pulp product, showing a formed pulp layer retained on an upper hot press mold, and a first reinforcement layer placed on a lower hot press mold;

[0035] FIG. 27 is a diagrammatic view of the manufacturing system of FIG. 26, but wherein the lower hot press mold is moved into alignment with the upper hot press mold;

[0036] FIG. 28 is a diagrammatic view of the manufacturing system of FIG. 26, but showing manufacturing steps subsequent to those shown in FIG. 27, wherein the upper hot press mold and the lower hot press mold are moved toward one another to compress the pulp layer and first reinforcement layer together with heat and pressure;

[0037] FIG. 29 is a diagrammatic view of the manufacturing system of FIG. 26, but showing manufacturing steps subsequent to those shown in FIG. 28, wherein the upper and lower hot press molds are separated, the lower hot press mold is moved out of alignment with the upper hot press mold, and a second reinforcement layer is placed on the pulp layer;

[0038] FIG. 30 is a diagrammatic view of the manufacturing system of FIG. 26, but showing manufacturing steps subsequent to those shown in FIG. 29, wherein the lower hot press mold is moved back into alignment with the upper hot press mold;

[0039] FIG. 31 is a diagrammatic view of the manufacturing system of FIG. 26, but showing manufacturing steps subsequent to those shown in FIG. 30, wherein the upper hot press mold and the lower hot press mold are moved toward one another to press the second reinforcement layer, the pulp layer and the first reinforcement layer together with heat and pressure;

[0040] FIG. 32 is a diagrammatic view of the manufacturing system of FIG. 26, but showing manufacturing steps subsequent to those shown in FIG. 31, wherein the upper and lower hot press molds are separated, the lower hot press mold is moved out of alignment with the upper hot press mold, and the manufactured multi-layer composite pulp product is retained on the upper hot press mold; and

[0041] FIG. 33 is a diagrammatic view of the manufacturing system of FIG. 26, but showing manufacturing steps subsequent to those shown in FIG. 32, wherein the manufactured multi-layer composite pulp product is shown being ejected from the upper hot press mold.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] Referring now to the drawings, like reference numerals designate identical or corresponding features throughout the several views.

[0043] Certain example embodiments of a multi-layer composite pulp product are shown generally at 100. Referring to FIGS. 1, 2 and 20, particular preferred embodiments of a multi-layer composite pulp product 100 may be in the form of a pallet. Referring to FIGS. 4-6, a multi-layer composite pulp product 100 may comprise a first pulp layer 102, a second pulp layer 104 and a reinforcement layer 106 disposed (e.g., fused) between the first pulp layer 102 and the second pulp layer 104.

[0044] Referring to FIGS. 1 and 2, the product 100 may be shaped to have a pattern of opposingly-disposed cavities 110 and protrusions 112. Such cavities 110 and protrusions 112 may take the form of, for example, stiffener channels 130 or pallet feet 132.

[0045] Relatedly, referring to FIG. 6, the first pulp layer 102 may have a first pattern 108a of opposingly-defined cavities 110a and protrusions 112a; the second pulp layer 104 may have a second pattern 108b of opposingly-defined cavities 110b and protrusions 112b; and the reinforcement layer 106 may have a reinforcement pattern 108c of opposingly-defined cavities 110c and protrusions 112c. In such embodiments of the product 100, the reinforcement pattern 108c is aligned with the first pattern 108a and the second pattern 108b.

[0046] Referring to FIGS. 1, 4 and 20, in certain embodiments of the product 100, particularly those in the form of a pallet, the product 100 may extend in generally planar fashion radially of a main axis 114. Referring to FIG. 6, in such embodiments of the product 100, the alignment of respective cavities and protrusions is preferably in a direction parallel to the main axis.

[0047] One or more of the various layers described herein may preferably be formed with a uniform wall thickness. For example, referring to FIGS. 4 and 5, in particular embodiments of the product 100, the first pulp layer 102 may have a uniform wall thickness 116, the second pulp layer 104 may have a uniform wall thickness 118, and the reinforcement layer 106 may have a uniform wall thickness 120. In certain such embodiments of a product 100, the uniform wall thickness 120 of the reinforcement layer 106 may be different from the uniform wall thickness (116, 118) of both the first pulp layer 102 and the second pulp layer 104. Additionally, the uniform wall thicknesses (116, 118) of the first pulp layer 102 and the second pulp layer 104 may be the same.

[0048] Regarding the material of the various layers of the product 100, the reinforcement layer 106 may preferably be comprised of a plastic (e.g., recycled plastic), a metallic mesh, a metallic sheet (e.g., metal board), some combination thereof or the like. The pulp layers (102, 104) may comprise raw material such as recycled paper and/or corrugated boxes. In addition, the pulp layers may comprise chemical fibers such as waste carpet, at a concentration of, for example, 2-5% of the overall weight of the dried pulp layer. In particular embodiments of the product 100, the first pulp layer 102 and the second pulp layer 104 may comprise alkyl ketene dimer (AKD) sizing agent, or the like.

[0049] Certain example implementations of a process for manufacturing a multi-layer composite pulp product 100 are represented by the sequence illustrated in FIGS. 7-19. In particular, FIGS. 7-19 diagrammatically illustrate a system 200 for manufacturing a multi-layer composite pulp product 100, as the system 200 proceeds through the sequence of the manufacturing process.

[0050] Referring to FIGS. 8 and 9, the manufacturing process may comprise fabricating a reinforcement layer 106. This fabrication may be by way of, for example, a reinforcement layer fabrication subsystem 202. The subsystem 202 may comprise, for example, a first fabrication element 204 and a second fabrication element 206. The fabrication elements may be, for example, complementary injection molding tools, metal stamping tools, or the like. For instance, in the case in which the reinforcement layer 106 is comprised of a plastic (e.g., recycled plastic), the fabrication elements (204, 206) may represent injection molding core/cavity tooling for forming the reinforcement layer 106 into the requisite shape. Alternatively, in the case in which the reinforcement layer 106 is comprised of a metal, such as sheet metal or metallic mesh, the fabrication elements (204, 206) may represent complimentary metal stamping (e.g., pressing) tooling for forming the reinforcement layer 106 into the requisite shape.

[0051] Referring to FIGS. 8-10, the manufacturing process may comprise forming a soggy first pulp layer 102. For example, a pulp reservoir 208 may be provided with fluid pulp 210. The fluid pulp may have a pulp concentration of, for example, 1.5% to 4% pulp. A forming mold 212 may be partially or entirely submerged into the fluid pulp 210, where a quantity 220 of fluid pulp is applied to the forming mold 212. The quantity of fluid pulp may then be dehydrated (e.g., by way of vacuum dehydration) on the forming mold 212 for a set time for forming and dehydration. Such forming and dehydration may preferably leave the first pulp layer 102 formed in shape, but still soggy (i.e., not fully dehydrated).

[0052] Referring to FIGS. 10-12, the soggy first pulp layer 102 may be transferred onto a lower hot press mold 216 by way of a transfer mold 214. More particularly, referring to FIG. 10, the transfer mold 214 may drop and absorb the formed soggy first pulp layer 102. Referring to FIG. 11, the transfer mold 214 may then move up and slide over the top of the lower hot press mold 216. Referring to FIG. 12, the soggy first pulp layer 102 may be dropped, or blown via compressed air, into the lower hot press mold 216.

[0053] Referring to FIGS. 13 and 14, the reinforcement layer may be placed the on the soggy first pulp layer 102, either by manual or machine operation.

[0054] Referring to FIGS. 14 and 15, a soggy second pulp layer 104 may be formed and transferred in a manner similarly or identical to that of the soggy first pulp layer 102. Referring to FIG. 16, the soggy second pulp layer 104 may be dropped, or blown via compressed air, into positioning on the reinforcement layer. As a result, a precursor wet composite 222 may be defined by the soggy first pulp layer 102, the reinforcement layer 106, and the soggy second pulp layer 104 being in a stacked configuration on the lower hot press mold 216.

[0055] Referring to FIGS. 6 and 16, the fabricated reinforcement layer 106 may have a reinforcement pattern 108c of opposingly-defined cavities 110c and protrusions 112c. The formed soggy first pulp layer 102 may have a first pattern 108a of opposingly-defined cavities 110a and protrusions 112a. The formed soggy second pulp layer 104 may have a second pattern 108b of opposingly-defined cavities 110b and protrusions 112b. In the aforementioned stacked configuration, the reinforcement pattern 108c is preferably in alignment with the first pattern 108a and the second pattern 108b.

[0056] Referring to FIG. 17, the precursor wet composite 222 may be dried at a selected heating temperature and under a selected pressure. For example, referring to FIG. 17, the lower hot press mold 216 may slide directly under a corresponding upper hot press mold 218. Referring to FIG. 18, the step of drying may then involve compression of the precursor wet composite 222 between the lower hot press mold 216 and an upper hot press mold 218 at the selected temperature and pressure for a set time. The heating temperature may be, for example, from 150 to 260 degrees Celsius. The selected pressure may be, for example, from 19-29 PSI.

[0057] In particular embodiments of the process for manufacturing a multi-layer composite pulp product 100, a quantitative waterproof preservative may be added to the fluid pulp 210 to avoid the influencing the strength of the product/pallet in wet operational environment. For example, the fluid pulp 210 may have alkyl ketene dimer (AKD) sizing agent (e.g., 0.8% to 2%) added. Thus, the soggy first pulp layer 102 and the soggy second pulp layer 104 may comprise a percentage of alkyl ketene dimer (AKD) sizing agent.

[0058] Referring to FIG. 19, after the step of drying (e.g., after the set time), the upper hot press mold 218 and lower hot press mold 216 may be separated, and the dried multi-layer pulp product 100 removing therefrom. For example, under the action of compressed air and a removal device, the dried multi-layer pulp composite product 100 may be removed to complete the processing.

[0059] Referring to FIGS. 21 and 22, an alternate implementation of a multi-layer composite pulp product is shown generally at 300. Referring to FIGS. 22-24, the product 300 may comprise a pulp layer 302 and an upper reinforcement layer 306. The pulp layer 302 may have a lower face 322 and an upper face 324 disposed oppositely of one another. The pulp layer 302 may have a core pattern 308a of opposingly-defined cavities 310a and protrusions 312a. The upper reinforcement layer 306 may be comprised of molded plastic sheet and may have an upper reinforcement pattern 308c of opposingly-defined cavities and protrusions. The upper reinforcement layer may preferably be affixed to the upper face 324 with the upper reinforcement pattern 308c being aligned with the core pattern 308a.

[0060] Referring to FIGS. 22-24, particular embodiments of the product 300 may further comprise a lower reinforcement layer 304 comprised of molded plastic sheet and having a lower reinforcement pattern 308b of opposingly-defined cavities and protrusions. The lower reinforcement layer 304 may preferably be affixed to the lower face 322 with the lower reinforcement pattern 308b being aligned with the core pattern 308a.

[0061] Referring to FIGS. 21-22, in certain embodiments of the product 300, the product 300 may extend in generally planar fashion radially of a main axis 314 so as to form, for example, a pallet shape. In such embodiments, the alignments of the agreement patters are preferably in a direction parallel to the main axis 314.

[0062] Referring to FIGS. 22-23, in particular embodiments of the product 300, the pulp layer 302 may have a uniform wall thickness 316, the lower reinforcement layer 304 may have a uniform wall thickness 318, and the upper reinforcement layer 306 may have a uniform wall thickness 320. In certain such embodiments, the uniform wall thicknesses of the reinforcement layers (304, 306) may be different from the uniform wall thickness of the pulp layer 302.

[0063] In certain preferred environment of the product 300, the reinforcement layers may be comprised of a recycled plastic.

[0064] Certain example implementations of a process for manufacturing a multi-layer composite pulp product 300 are represented by the sequence illustrated in FIGS. 25-33. In particular, FIGS. 26-33 diagrammatically illustrate one example of a system 400 for manufacturing a multi-layer composite pulp product 300, as the system 400 proceeds through the sequence of the manufacturing process.

[0065] Referring to FIG. 25, one or more plastic sheets 326 may be obtained. The plastic sheets 326 may preferably be comprised of a recycled plastic. Referring to FIGS. 24 and 25, a lower reinforcement layer 304 may be fabricated from a first plastic sheet 326 so as to have a lower reinforcement pattern 308b of opposingly-defined cavities and protrusions. Similarly, an upper reinforcement layer 306 may be fabricated from a second plastic sheet so as to have an upper reinforcement pattern 308c of opposingly-defined cavities and protrusions. This fabrication may preferably involve, for example, vacuum forming, stamping, or the like.

[0066] Referring to FIG. 26, a pulp layer 302 may be formed so as to have a core pattern 308a of opposingly-defined cavities and protrusions. The formed pulp layer 302 may initially be retained on an upper hot press mold 402. The lower reinforcement layer 304 may be placed on a lower hot press mold 404.

[0067] Referring to FIGS. 27-28, the pulp layer 302 may be placed on the lower reinforcement layer 304. Referring to FIG. 29, the upper reinforcement layer 306 may then be placed on the pulp layer 302, for example after the lower hot press mold 404 is moved out of alignment with the upper hot press mold 402.

[0068] Referring to FIGS. 30-31, the upper reinforcement layer 306, the pulp layer 302 and the lower reinforcement layer 304 may be pressed together, for example by way of mutual engagement between the upper hot press mold 402 and the lower hot press mold 404, with the lower and upper reinforcement patterns being aligned with the core pattern. This step of pressing may be at a first selected heating temperature and under a first selected pressure.

[0069] Referring to FIG. 28, particular implementations of a process for manufacturing a multi-layer composite pulp product 300 may further comprise, after the step of positioning the pulp layer 302 on the lower reinforcement layer 304, compressing the pulp layer 302 and lower reinforcement layer together 304. This step of compressing may be at a second selected heating temperature and under a second selected pressure.

[0070] With reference to the aforementioned steps of pressing and compressing, the heating temperatures may preferably from 150 to 260 degrees Celsius. Alternatively or in addition, the selected pressures may preferably be 19-29 PSI. In certain implementations of the manufacturing process, the first selected heating temperature may preferably be different from the second selected heating temperature. Likewise, in certain implementations of the manufacturing process, the first selected pressure may be different from the second selected pressure.

[0071] The following listing matches certain terminology used within this disclosure with corresponding reference numbers used in the non-limiting examples illustrated in the several figures. [0072] 100 multi-layer composite pulp product (e.g., pallet) [0073] 102 first pulp layer [0074] 104 second pulp layer [0075] 106 reinforcement layer [0076] 108 pattern (of cavities and protrusions) [0077] 108a pattern (of cavities and protrusions of first pulp layer) [0078] 108b pattern (of cavities and protrusions of second pulp layer) [0079] 108c pattern (of cavities and protrusions reinforcement layer) [0080] 110 cavity (of pulp product) [0081] 110a cavity (of first pulp layer) [0082] 110b cavity (of second pulp layer) [0083] 110c cavity (of reinforcement layer) [0084] 112 protrusion (of pulp product) [0085] 112a protrusion (of first pulp layer) [0086] 112b protrusion (of second pulp layer) [0087] 112c protrusion (of reinforcement layer) [0088] 114 main axis [0089] 116 wall thickness of first pulp layer [0090] 118 wall thickness of second pulp layer [0091] 120 wall thickness of reinforcement layer [0092] 122 first side of reinforcement layer [0093] 124 second side of reinforcement layer [0094] 126 load (e.g., bearing it weight on pallet 100) [0095] 128 substrate (e.g., ground, floor or storage shelf) [0096] 130 stiffener channels [0097] 132 feet [0098] 200 manufacturing system [0099] 202 reinforcement layer fabrication subsystem [0100] 204 first fabrication element (e.g., stamping or injection molding core/cavity tool) [0101] 206 second fabrication element (e.g., stamping or injection molding core/cavity tool) [0102] 208 pulp reservoir [0103] 210 fluid pulp [0104] 212 forming mold [0105] 214 transfer mold [0106] 216 lower hot press mold [0107] 218 upper hot press mold [0108] 220 quantity of fluid pulp (e.g., applied to forming mold) [0109] 222 precursor wet composite [0110] 300 multi-layer composite pulp product (e.g., pallet) [0111] 302 pulp layer [0112] 304 lower reinforcement layer [0113] 306 upper reinforcement layer [0114] 308 pattern (of cavities and protrusions) [0115] 308a core pattern (of cavities and protrusions of pulp layer) [0116] 308b lower reinforcement pattern (of cavities and protrusions of lower reinforcement layer) [0117] 308c upper reinforcement pattern (of cavities and protrusions of upper reinforcement layer) [0118] 310 cavity (of pulp product) [0119] 310a cavity (of pulp layer) [0120] 310b cavity (of lower reinforcement layer) [0121] 310c cavity (of upper reinforcement layer) [0122] 312 protrusion [0123] 312a protrusion (of pulp layer) [0124] 312b protrusion (of lower reinforcement layer) [0125] 312c protrusion (of upper reinforcement layer) [0126] 314 main axis [0127] 316 wall thickness of pulp layer [0128] 318 wall thickness of lower reinforcement layer [0129] 320 wall thickness of upper reinforcement layer [0130] 322 lower face of pulp layer [0131] 324 upper face of pulp layer [0132] 326 plastic sheet [0133] 400 manufacturing system [0134] 402 upper hot press mold [0135] 404 lower hot press mold

[0136] While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.