Building panel with magnesium oxide-phosphate backcoating

Patent metadata

Field	Value
Publication number	US-2016230013-A1
Application number	US-201514619317-A
Country	US
Kind code	A1
Filing date	Feb 11, 2015
Priority date	Feb 11, 2015
Publication date	Aug 11, 2016
Grant date	—

Abstract

Methods for making building panels are described. The methods include combining water, an inorganic fiber, and one or more binders to form a slurry, wherein at least one of the binders comprises starch; shaping the slurry into a panel; applying a coating to a back side of the panel, the coating comprising a reaction product of magnesium oxide and a phosphate salt in the absence of an amino alcohol; and drying the panel. Building panels are also described.

First claim

What is claimed is:

1 . A method for making a building panel comprising:
combining water, an inorganic fiber, and one or more binders to form a slurry, wherein at least one of the binders comprises starch; shaping the slurry into a panel; applying a coating to a back side of the panel, the coating comprising a reaction product of magnesium oxide and a phosphate salt in the absence of an amino alcohol; and drying the panel.

2 . The method of claim 1 wherein the phosphate salt comprises at least one of potassium phosphate, and sodium phosphate.

3 . The method of claim 1 wherein the magnesium oxide is a high reactivity magnesium oxide.

4 . The method of claim 1 wherein a molar ratio of the magnesium oxide to the phosphate salt is in a range of about 0.1 to about 0.9.

5 . The method of claim 1 wherein applying the coating to the back side of the panel comprises applying the coating over a portion of the back side of the panel.

6 . The method of claim 1 wherein applying the coating to the back side of the panel comprises applying the coating over all of the back side of the panel.

7 . The method of claim 1 wherein applying the coating to the back side of the panel comprises:
preparing a dispersion of the magnesium oxide;
preparing a dispersion of the phosphate salt; and
combining the magnesium oxide and phosphate dispersions and immediately applying the magnesium oxide dispersion and the phosphate salt dispersion to the back side of the panel.

8 . The method of claim 8 further comprising adding an acid to at least one of the magnesium oxide dispersion and the phosphate salt dispersion.

9 . The method of claim 1 wherein the coating further comprises at least one of a filler, a flow aid, and a retarder.

10 . The method of claim 1 wherein the coating is applied in an amount of less than about 25 grams of solids per square foot.

11 . The method of claim 1 wherein the slurry further comprises at least one of expanded perlite and a renewable fiber.

12 . The method of claim 11 wherein the renewable fiber is cellulose fiber.

13 . A building panel comprising;
a base mat comprising an inorganic fiber, and one or more binders, wherein at least one of the binders comprises starch; a coating on a back side of the base mat, the coating being the reaction product of magnesium oxide and a phosphate salt.

14 . The building panel of claim 13 wherein the phosphate salt comprises at least one of potassium phosphate, and sodium phosphate.

15 . The building panel of claim 13 wherein the magnesium oxide is a high reactivity magnesium oxide.

16 . The building panel of claim 13 wherein a molar ratio of the magnesium oxide to the phosphate salt is in a range of about 0.1 to about 0.9.

17 . The building panel of claim 13 wherein the coating covers a portion of the back side of the panel.

18 . The building panel of claim 13 wherein the coating covers all of the back side of the panel.

19 . The building panel of claim 13 wherein the base mat further comprises at least one of expanded perlite and a renewable fiber.

20 . The building panel of claim 13 wherein the coating is applied in an amount of less than about 25 grams of solids per square foot.

Assignees

• Usg Interiors Llc

Inventors

• Englert Mark H
• Yeung Lee K

Classifications

• C09D1/00 Primary

  Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances · CPC title

• B05D3/007

  After-treatment · CPC title

• C04B41/5092 Primary

  Phosphate cements · CPC title

• C04B26/28

  Polysaccharides or derivatives thereof · CPC title

• C04B2111/00094

  Sag-resistant materials · CPC title