BUILDING PRODUCT

Abstract

A building product in the form of an internal lining board. The board is made up of a mixture of a food crop byproduct, a binder, a water reducing agent, cellulose, and water. The mixture is provided between two sheets of lining paper.

Claims

1. A method of producing an internal lining board, the method comprising: mixing at least a binder, a water reducing agent and water to form a slurry; mixing at least a food crop byproduct with the slurry to form a paste; and locating the paste between two sheets of lining paper.

2. The method according to claim 1, wherein locating the paste between two sheets of lining paper comprises distributing the paste across a continuously moving belt onto a sheet of the two sheets of lining paper.

3. The method according to claim 1, wherein locating the paste between two sheets of lining paper comprises extruding the paste between the two sheets of lining paper.

4. The method according to claim 3, wherein the paste is extruded between a bottom layer of the two sheets of lining paper and a top layer of the two sheets of lining paper moving around a roller.

5. The method according to claim 3, wherein the paste extruded between the two sheets of lining paper forms a composite, and heat is applied to the composite.

6. The method according to claim 5, wherein the heat is applied via direct contact, or indirectly through convection or infrared heat.

7. The method according in claim 5, wherein the paste is distributed across a continuously moving belt onto a sheet of the two sheets of lining paper, and the heat is applied through conduction in the continuously moving belt.

8. The method according to claim 1, wherein the water is heated before the mixing of the binder, the water reducing agent and the water to form a slurry.

9. The method according to claim 8, wherein the water is heated up to 90? C. before the mixing.

10. The method according to claim 1, wherein locating the paste between the two sheets of lining paper forms at least part of an internal lining board, and the method further comprises using vibrating pads or rollers to flatten the internal lining board.

11. The method according to claim 1, wherein locating the paste between the two sheets of lining paper forms at least part of an internal lining board, and the method further comprises cutting the lining board.

12. The method according to claim 11, wherein the lining board is cut using a water jet cutter.

13. The method according to claim 1, wherein locating the paste between the two sheets of lining paper forms at least part of an internal lining board, and the method further comprises drying the internal lining board.

14. The method according to claim 13, wherein the density of the lining board after drying is between 500 and 750 kg/m.sup.3.

15. The method according to claim 1, wherein the lining paper is recycled.

16. The method according to claim 1, wherein the lining paper has a weight of between 150 and 210 g/m.sup.2.

17. The method according to claim 1, wherein the binder comprises lime and a cementitious product.

18. The method according to claim 1, wherein the food crop byproduct comprises any of: common wheat, oats, rapeseed, barley straw, giant miscanthus, bamboo, flax, rice straw, corn straw, sugarcane bagasse, or sisal straw.

19. A method of producing an internal lining board, the method comprising: mixing at least a binder and water to form a slurry; mixing at least a food crop byproduct with the slurry to form a paste; and locating the paste between two sheets of lining paper.

20. A method of producing an internal lining board, the method comprising: mixing at least a binder, a water reducing agent and water to form a slurry, wherein the binder includes lime and a cementitious product; mixing at least a food crop byproduct with the slurry to form a paste; distributing the paste across a continuously moving belt onto a bottom sheet of lining paper; extruding the paste between the bottom sheet of lining paper and a top sheet of lining paper to form at least part of an internal lining board; using vibrating pads or rollers to flatten the internal lining board; cutting the internal lining board; and drying the internal lining board in a drying chamber.

Description

[0073] Example 1 is a standard product. In Example 2 a greater proportion of cementitious product to hydrated lime is provided to increase hardness, sheer strength and compressive strength. Compressive strength and sheer strength for instance increase the ability for the product to take a screw. This increase in compressive strength will increase flexural rigidity.

[0074] Example 3 provides a more thermally and acoustically insulative product, with improved hygrothermal performance.

[0075] The finished products provide a paper faced lining board which can be cut to size by cutting the sheets with a knife and snapping the board within. The product can be attached to stud work or walls with screws in a conventional manner. The board can have square edges or tapered edges to permit jointing.

[0076] The products thus formed provide for commercial scale production of compostable materials which are fast setting. The drying process is without high temperatures or pressure and this helps to reduce the embodied energy and cost to make the product. The cellulose used has been found to improve the strength of the board and also create a bond between the paper and the board materials.

[0077] The inclusion of cellulose to the cementitious binder also improves the interface between the binder and the aggregate, creating a more structurally homogeneous composite. Conventional internal lining boards do not use compostable materials and can also use a high energy input during production. The product thus formed is lighter weight than conventional products, reducing health and safety risk at the point of installation, as well as embodied energy for transportation.

[0078] Various modifications may be made without departing from the scope of the invention. For instance retardants such as citric acid may be included if it is required to slow down curing, or accelerants such as sodium carbonate may be used if required to speed up curing. Air entraining agents may be used to improve flow of the paste in the process. Different drying conditions may be applied. The materials may be used in different proportions or combinations of those indicated. Other food crop byproducts may be suitable for use.

[0079] Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.