Planar material and method for the production thereof

Patent metadata

Field	Value
Publication number	US-12441024-B2
Application number	US-202017604532-A
Country	US
Kind code	B2
Filing date	Jan 9, 2020
Priority date	Apr 18, 2019
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

The invention relates to a planar material, comprising lignocellulose fibers and binding agents. In order to provide a planar material that using fibers has reduced swelling, it is provided that the proportion of the binding agent has more than 50 wt % of the planar material. The invention also comprises a method for producing the planar material.

First claim

The invention claimed is:

1. A method for producing a planar material, comprising lignocellulose fibers ( 5 ) and a binder comprising a binding agent and a plasticizing additive, wherein the proportion of the binding agent with the plasticizing additive is more than 50 wt % of the planar material ( 1 ), wherein the plasticizing additive is not used as the main component of the binder, comprising the steps of:
providing lignocellulose fibers ( 5 );
providing the binding agent, wherein the binding agent has melamine resin, formaldehyde resin, phenol resin, methylene diphenylisocyanate (MDI), also in emulsified form as eMDI, polymeric diphenylmethane diisocyanate (PDMI), polyurethane, or mixtures of the aforementioned binding agents as well as the plasticizing additive;
applying the binding agent with the plasticizing additive to the fibers ( 5 ), wherein the plasticizing additive is applied with the binding agent to the fibers,
forming a fiber cake from the fibers provided with the binding agent and with the plasticizing additive;
pressing the fiber cake in a press while curing the binding agent to create a planar material ( 1 ) having a single layer from an upper face ( 2 ) to a lower face ( 3 ) of the planar material, wherein the plasticizing additive and the binding agent are used in a ratio of 0.2:1 to 0.01:1.

2. The method according to claim 1 , wherein acrylate, styrene acrylate, polyurethane, polyvinyl acetate, ethylene vinyl acetate, mono- or diethylene glycol are added as the plasticizing additive of the planar material.

3. The method according to claim 2 , wherein the plasticizing additive is used as a solid.

4. The method according to claim 2 , wherein the plasticizing additive is applied to the fibers before or after the binding agent or is mixed with the binding agent before being applied to the fibers and is then applied to the fibers.

5. The method according to claim 1 , wherein a continuous or a discontinuous hot press is used for producing the planar material.

6. The method according to claim 1 , wherein the pressing temperature is 140° C. to 220° C.

7. The method according to claim 1 , wherein the pressing pressure is 0.3 N/mm 2 to 5.5 N/mm 2 .

8. The method according to claim 1 , wherein the pressing duration is 6 seconds/mm of board thickness to 60 seconds/mm of board thickness.

9. The method according to claim 1 , wherein, when applying the binding agent and the plasticizing additive, the fibers are subsequently dried.

10. The method according to claim 1 , wherein the binding agent is provided in liquid form.

11. The method according to claim 1 , wherein the pressing step comprising pressing the fiber cake to create the planar material having a thickness of between 3 mm and 80 mm.

12. The method according to claim 1 , wherein the planar material ( 1 ) comprises natural fibers, synthetic fibers, inorganic or organic fibers, or mixtures of fibers.

13. The method according to claim 12 , wherein the organic, natural fibers comprise lignocellulose fibers from renewable raw materials.

14. The method according to claim 12 , wherein the synthetic fibers comprise fibers made of thermoplastic material.

15. The method according to claim 12 , wherein the inorganic fibers comprise fibers made of mineral, ceramic, or glass materials.

16. The method according to claim 1 , wherein the fibers comprise atro wood, and wherein a proportion of binding agent in relation to atro wood is more than 101 wt %.

17. The method according to claim 1 , wherein the planar material ( 1 ) has an aggregate, non hygroscopic or non-swelling fillers.

18. The method according to claim 17 , wherein mineral, ceramic, synthetic, or glass particles are used as the aggregate.

19. The method according to claim 1 , wherein the planar material ( 1 ) has hydrophobing agents.

20. The method according to claim 1 , wherein the planar material has a homogeneous composition from the upper face to the lower face.

Assignees

• SWISS KRONO Tec AG

Inventors

• Braun Roger
• Hasch Joachim
• Schwind Volker
• Kalwa Norbert

Classifications

• C09J175/04

  Polyurethanes · CPC title

• C08L97/02

  Lignocellulosic material, e.g. wood, straw or bagasse {(manufacture of articles made from lignocellulosic material by dry processes B27N)} · CPC title

• C08G2170/20

  Compositions for hot melt adhesives · CPC title

• B27N3/04

  from fibres · CPC title

• B27N3/002 Primary

  characterised by the type of binder (compositions of macromolecular compounds C08L) · CPC title