Engineered molded fiberboard panels and methods of making and using the same

Patent metadata

Field	Value
Publication number	US-8936699-B2
Application number	US-201213662737-A
Country	US
Kind code	B2
Filing date	Oct 29, 2012
Priority date	Mar 28, 2008
Publication date	Jan 20, 2015
Grant date	Jan 20, 2015

Abstract

A fiberboard panel is formed from at least one corrugated sheet of molded cellulose fiber material having alternating ribs and grooves. The corrugated sheet or panel is formed by a wet processing method including successive cold and hot press steps in which a wet mat is pressed between an opposing perforated platen and non-perforated, elastomeric material platen of cross-sectional shape substantially matching the desired panel shape and dimensions.

First claim

The invention claimed is:

1. A method of molding a fiberboard panel in a predetermined three-dimensional non-planar shape, comprising the steps of:
hydropulping a furnish of cellulose fiber material into a water solution and mixing to separate the fibers into a pulp;
pouring the pulp onto a first surface of a perforated mold screen in a former box, the screen having opposite first and second surfaces and a shape including a plurality of protrusions corresponding to a first side of the predetermined three-dimensional panel shape;
removing water from the pulp through the mold screen by applying a vacuum to the second surface of the screen to leave a wet fiber mat on the screen;
removing the sides of the box and transferring the mold screen carrying the wet fiber mat into a first press between a first, perforated platen of a shape substantially corresponding to the mold screen shape including a plurality of protrusions corresponding to a first side of the predetermined three-dimensional panel shape, and a second platen of the first press, the second platen being of non-porous elastomeric material and having a second plurality of protrusions corresponding to the second side of the predetermined three-dimensional panel shape;
placing the mold screen onto the first, perforated platen of the first;
moving the second platen of elastomeric material into engagement with the wet fiber mat to close the first press, whereby a plurality the second plurality of protrusions extend in between the at least some of the protrusions of the first press;
pressing the opposing first and second platens towards each other to squeeze the wet fiber mat between the platens and squeeze water out of the mat through the openings in the mold screen and first platen; and
hot pressing the fiber mat to remove at least substantially all of the water from the mat and form a finished panel.

2. The method of claim 1 , wherein hot pressing the fiber mat comprises separating the platens of the first press and transferring the mold screen and fiber mat onto a perforated first platen of a second press having an opposing second platen of non-porous elastomeric material, the first press comprising a cold press and the second press comprising a hot press, the first platen of the hot press having a cross-sectional shape similar to that of the first platen of the cold press, and the second platen of the hot press having a cross-sectional shape similar to that of the second platen of the cold press;
closing the platens of the hot press on the cold-pressed wet mat and applying pressure and heat to the mat to remove additional water by squeezing and vaporization until the mat has reached a desired densification and is substantially moisture free; and
separating the hot platens and removing the mold screen and finished panel from the hot press.

3. The method of claim 2 , wherein the non-porous elastomeric platens of the hot and cold presses each have at least a first face facing the first platen having a shape substantially matching that of the first platen of the respective press.

4. The method of claim 1 , wherein the non-porous elastomeric platen has at least a first face facing the first platen having a shape substantially matching that of the first platen and mold screen.

5. The method of claim 1 , wherein the mold screen has a corrugated shape of alternating ribs and grooves.

6. The method of claim 5 , further comprising cutting a series of spaced slits through the ribs on a first face of the finished panel to form at least one slotted portion along at least part of the length of the panel, each slit terminating short of the opposing, second face of the panel.

7. The method of claim 6 , further comprising bending the panel at the slotted portion to form a curve.

8. The method of claim 7 , wherein the panel is bent with the first face and slots facing inward into the curve and the second, unslotted face facing outward.

9. The method of claim 1 , wherein the finished panel is flat.

10. The method of claim 1 , wherein the finished panel is three dimensional.

11. A method of forming a fiberboard panel having at least one curve, comprising:
hydropulping cellulose fibers and water to form a slurry;
pouring the slurry over a corrugated form having alternating ribs and grooves corresponding to a predetermined corrugated panel shape;
removing water from the slurry to form a mat having a shape corresponding to the form shape;
pressing the mat to remove at least some water from the mat using a first platen having the corrugated shape, and a second platen having a mirror image of the corrugated shape;
hot pressing the formed mat to remove at least substantially all of the water from the mat, forming a corrugated panel of bonded cellulose material;
cutting a series of slits along at least part of the length of the panel to form a slotted panel portion, the slits extending through the ribs on a first face of the panel and terminating short of the peaks of the ribs on an opposite, second face of the panel; and
bending the panel at the slotted panel portion to form a curve.

12. The method of claim 11 , wherein the panel is bent so that the slots are on the inside of the curve.

13. The method of claim 12 , wherein the panel is bent until the inner ends of the slits close together.

14. The method of claim 12 , wherein adhesive is placed at the outer end of each slit to seal the outer end of the slit shut when the curve is formed.

15. A method of molding a fiberboard panel in a predetermined three-dimensional non-planar shape, comprising the steps of:
hydropulping a furnish of cellulose fiber material into a water solution and mixing to separate the fibers into a pulp;
pouring the pulp onto a first surface of a perforated mold screen in a former box;
removing water from the pulp through the mold screen by applying a vacuum to the second surface of the screen to leave a wet fiber mat on the screen;
transferring the mold screen carrying the wet fiber mat into a first press, including: positioning the mold screen between a first perforated platen and a second elastomeric platen, the first platen being perforated of a shape substantially corresponding to the mold screen shape including a plurality of protrusions corresponding to a first side of the predetermined three-dimensional panel shape, and the second platen including a substantially elastomeric material having a second plurality of protrusions corresponding to the second side of the predetermined three-dimensional panel shape, the elastomeric material placed on a rigid base having a shape that is different from that of an operating surface of the elastomeric material;
pressing the opposing first and second platens towards each other to squeeze the wet fiber mat between the platens and squeeze water out of the mat through the openings in the mold screen and first platen, whereby a plurality the second plurality of protrusions extend in between the at least some of the protrusions of the first press; and
hot pressing the fiber mat to remove at least substantially all of the water from the mat and form a finished panel.

Assignees

• Noble Environmental Technologies Corp
• Us Agriculture

Inventors

• Noble Robert
• Hunt John F
• Newburn Timothy L
• Gu Hongmei

Classifications

• E04F13/16

  of fibres or chips, e.g. bonded with synthetic resins {, or with an outer layer of fibres or chips (E04F13/0864 takes precedence)} · CPC title

• B32B3/12

  characterised by a layer of regularly- arranged cells, e.g. a honeycomb structure · CPC title

• Y10T428/24694

  Parallel corrugations · CPC title

• Y10T428/1348

  Cellular material derived from plant or animal source [e.g., wood, cotton, wool, leather, etc.] · CPC title

• B32B3/10

  characterised by a discontinuous layer, i.e. formed of separate pieces of material · CPC title