Fibrous mat-faced gypsum board

• US 4,810,569 A
• Filed: 03/02/1987
• Issued: 03/07/1989
• Est. Priority Date: 02/27/1984
• Status: Expired due to Term

• Current Assignee: G-P Gypsum Corporation (Golden Eagle Industries, Inc.)
• Original Assignee: Georgia-Pacific Corporation
• Inventors: Randall, Brian G., Lehnert, Charles W.
• Primary Examiner(s): HERBERT JR, THOMAS
• Application Number:
  US07/020,872
• Time in Patent Office: 736 Days
• Field of Search: 428/703, 428/285, 428/489, 428/484, 428/311.5, 428/312.4, 428/322.7, 428/171, 428/228, 428/332, 428/337, 428/426, 428/539, 428/535, 156/40, 156/42, 156/39, 156/41, 156/44, 156/71, 346/348, 106/111, 206/417, 52/481
• US Class Current: 442/386
• CPC Class Codes: B28B 19/0092 to webs, sheets or the like, e.g. of paper, cardboard
• CPC Class Codes: B28B 23/0006 the reinforcement consisting of aligned, non-metal reinforcing elements
• CPC Class Codes: B32B 13/14 next to a fibrous or filamentary layer
• CPC Class Codes: E04C 2/043 of plaster E04C2/049 takes precedence
• CPC Class Codes: E04C 2/284 at least one of the materials being insulating
• CPC Class Codes: E04C 2/288 composed of insulating material and concrete, stone or stone-like material
• CPC Class Codes: E04D 11/02 Build-up roofs, i.e. consisting of two or more layers bonded together in situ, at least one of the layers being of watertight composition gravelling of flat roofs E04D7/00; venting or ventilation E04D13/17
• CPC Class Codes: E04D 13/1643 the roof structure being formed by load bearing corrugated sheets, e.g. profiled sheet metal roofs
• CPC Class Codes: E04D 13/1668 the insulating material being masses or granules applied in situ
• CPC Class Codes: E04F 13/047 Plaster carrying meshes
• CPC Class Codes: Y10T 428/232 Encased layer derived from inorganic settable ingredient
• CPC Class Codes: Y10T 428/237 Noninterengaged fibered material encased [e.g., mat, batt, etc.]
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 428/266 of base or substrate
• CPC Class Codes: Y10T 442/665 Including a layer derived from a water-settable material [e.g., cement, gypsum, etc.]

Abstract

An exterior finishing system for a building. including particularly an exterior insulation system, which includes a fibrous mat-faced gypsum board, preferably a board in which the set gypsum core thereof is water resistant, and preferably one in which the set gypsum core is sandwiched between two sheets of porous glass mat, with the outer surface of at least one of said mats being substantially free of set gypsum, and means for preparing the board, including control of the viscosity of the aqueous gypsum slurry from which the set gypsum core of the board is formed. Also, the use of fibrous mat-faced gypsum board as the shaft liner panel in a shaft wall assembly.

Claims

1. Gypsum board comprising a set gypsum core sandwiched between two sheets of porous glass mat, each of which has an inner and outer surface, said mat comprising randomly distributed glass fibers bonded by an adhesive material, the inner surface of each of said mats adhered to said gypsum core by a portion of the set gypsum comprising said core, the outer surface of one of said mats having portions thereof coated with set gypsum comprising portions of the set gypsum of said core, and the outer surface of the other of said mats being substantially free of set gypsum.

2. Gypsum board according to claim 1 wherein said mat is a glass fiber mat comprising randomly distributed glass filaments bonded by an adhesive material.

3. Gypsum board in accordance with claim 1 wherein each of said mats comprises randomly distributed glass filaments bonded by an adhesive material, wherein said gypsum-coated mat is substantially penetrated by set gypsum over substantial area portions of the outer surface thereof, and wherein the set gypsum of the core penetrates but part-way into the thickness of the other of said mats.

4. Gypsum board in accordance with claim 3 wherein about 45 to about 55% of the outer surface of said gypsum-coated mat is substantially penetrated by the set gypsum.

5. Gypsum board in accordance with claim 1 or 3 in the form of a package in which two of said boards are packaged with said gypsum-free outer surfaces in face to face relationship and in which said gypsum-coated outer surfaces form the outer surfaces of said package.

6. Gypsum board comprising a set gysum core sandwiched between two sheets of porous glass mat, each of which has an inner and outer surface and a predetermined thickness, said mat comprising randomly distributed glass fibers bonded by an adhesive material, the inner surface of each of said mats adhered to said gypsum core by set gypsum of said core penetrating but part-way into the thickness of each of said mats, and wherein the outer surface of each of said mats is substantially free of set gypsum.

7. Gypsum board comprising a set gypsum core sandwiched between two sheets of porous glass mat, each of which has an inner and outer surface, said mat oomprising randomly distributed glass fibers bonded by an adhesive material, the inner surface of each of said mats adhered to said gypsum core by set gypsum of said core penetrating but part-way into the thickness of each of said mats, with the interstices between the fibers at the inner surface of each of said mats being substantially filled with set gypsum, and wherein the outer surface of each of said mats is substantially free of set gypsum.

8. Gypsum board comprising the set product of an aqueous slurry of calcined gypsum of predetermined viscosity sandwiched between underlying and overlying sheets of porous glass mat, each of which has an inner and outer surface and a predetermined thickness, said mat comprising randomly distributed glass fibers bonded by an adhesive material, wherein the relationship of the viscosity of said slurry to the porosity and thickness of each of said mats is such that said slurry penetrates but part-way into the thickness of each of said mats as said slurry sets to form a set gypsum core having adhered thereto said mats, the outer surfaces of which are substantially free of set gypsum.

9. Gypsum board according to claim 8 wherein the thickness of each of said mats is about 15 to about 40 mils and wherein the viscosity of said slurry is about 5000 to about 7000 cp at 70°

F.

10. Gypsum board according to claim 9 wherein said slurry penetrates about 10 to 50% of the thickness of the overlying mat.

11. Gypsum board according to claim 9 wherein said slurry penetrates up to about 50% of the thickness of said underlying mat.

12. Gypsum board according to claim 8, 9, 10, or 11 wherein said set product includes paper fiber.

13. Gypsum board according to claim 12 wherein the air permeability of each of said mats is about 700 CFM/sq. ft.

14. Gypsum board according to claim 12 wherein the thickness of each of said mats is about 25 to about 35 mils.

15. Gypsum board comprising a set gypsum core sandwiched between two sheets of porous glass fiber mat, each of the mats having an inner and outer surface, the inner surface of each of said mats adhered to said gypsum core by set gypsum of said core penetrating but part-way into the thickness of each of said mats, with the interstices between the fibers at the inner surface of each of said mat being substantially filled with set gypsum, and the outer surface of each of said mats being substantially free of set gypsum and comprising many interstices into which an adhesive composition can flow and bond.

16. Gypsum board according to claim 15 wherein each of said mats comprises randomly distributed glass fibers bonded by an adhesive material.

17. A process for manufacturing in continuous fashion a glass fiber mat-faced gypsum board of indefinite length comprising:

(A) forming an aqueous slurry of calcined gypsum;

(B) continuously feeding said aqueous slurry onto an underlying, moving and supported porous glass fiber mat having an outer surface;

(C) forming said deposited slurry as it is carried on said moving mat into a panel-like shape;

(D) applying to the top surface of said panel-like shape of slurry an overlying porous glass fiber mat of predetermined thickness;

(E) maintaining the viscosity of said slurry at a value such that said underlying mat is substantially penetrated by said slurry over substantial area portions of the outer surface thereof, and at a value such that portions of said slurry penetrate but part-way into the thickness of said overlying mat; and

(F) maintaining said panel-like shape as said calcined gypsum sets to form a set gypsum core having adhered to one surface thereof said underlying glass fiber mat which is substantially penetrated by set gypsum over substantial area portions of the outer surface thereof, and the core having adhered to its other surface said overlying glass fiber mat, the outer surface of which is substantially free of set gypsum.

18. A process according to claim 17 wherein said mat comprises randomly distributed glass filaments bonded by an adhesive material and wherein the viscosity of said slurry is about 5000 to about 7000 cp at 70°

F.

19. A process for manufacturing in continuous fashion a glass fiber mat-faced gypsum board of indefinite length comprising:

(A) forming an aqueous slurry of calcined gypsum;

(B) continuously feeding said aqueous slurry onto an underlying, moving and supported porous glass fiber mat having an outer surface and a predetermined thickness;

(C) forming said deposited slurry as it is carried on said moving mat into a panel-like shape;

(D) applying to the top surface of said panel-like shape of slurry an overlying porous glass fiber mat having an outer surface and a predetermined thickness;

(E) maintaining the viscosity of said slurry at a value such that portions of said slurry penetrate but part-way into the thickness of each of said underlying and overlying mats; and

(F) maintaining said panel-like shape as said calcined gypsum sets to form a set gypsum core having adhered thereto said mats, the outer surfaces of which are substantially free of set gypsum.

22. A process according to claim 19 or 20, including adding to said slurry paper fibers.

23. A process according to claim 19, 20 or 21 wherein said mats are glass fiber mats comprising randomly distributed glass filaments bonded by an adhesive material.

24. A process according to claim 23 wherein the thickness of each of said mats is about 15 to about 40 mils.

25. A process according to claim 24, wherein the thickness of each of said mats is about 25 to about 35 mils.

26. A process according to claim 24, wherein the viscosity of said slurry is about 5000 to about 7000 cp at 70°

F.

27. A process according to claim 26, wherein the air permeability of each of said mats is about 700 CFM/sq. ft.

28. A process according to claim 19, 20 or 21 wherein said slurry penetrates up to about 50% of the thickness of said underlying mat.

29. A process according to claim 28 wherein said mats are glass fiber mats comprising randomly distributed glass filaments bonded by an adhesive material.

30. A process according to claim 19, 20 or 21 wherein said slurry penetrates about 10 to 50% of the thickness of the overlying mat.

31. A process according to claim 30 wherein said mats are glass fiber mats comprising randomly distributed glass filaments bonded by an adhesive material.

32. A process according to claim 31 wherein said slurry penetrates up to about 50% of the thickness of said underlying mat.

20. A process for manufacturing in continuous fashion a glass fiber mat-faced board of indefinite length comprising:

(A) forming an aqueous slurry of calcined gypsum;

(B) continuously feeding said aqueous slurry onto an underlying, moving and supported porous glass fiber mat having an inner and outer surface and a predetermined thickness;

(C) forming said deposited slurry as it is carried on said moving mat into a panel-like shape;

(D) applying to the top surface of said panel-like shape of slurry an overlying porous glass fiber mat having an inner and outer surface and a predetermined thickness;

(E) maintaining the viscosity of said slurry at a value such that the relationship between the viscosity of said slurry to the porosity and thickness of each of said underlying and overlying mats is such that said slurry penetrates but part-way into the thickness of each of said mats; and

(F) maintaining said panel-like shape as said calcined gypsum sets to form a set gypsum core to which said underlying and overlying mats are adhered by said set gypsum which substantially fills the interstices between the individual glass fibers at the inner surfaces of said mats, with the interstices between the individual fibers at the outer surfaces of said mats being substantially free of set gypsum.

21. A process for manufacturing in continuous fashion a glass mat-faced gypsum board of indefinite length comprising:

(A) forming an aqueous slurry of calcined gypsum;

(B) continuously feeding said aqueous slurry onto an underlying, moving and supported porous glass mat having an outer surface and a predetermined thickness;

(C) forming said deposited slurry as it is carried on said moving mat into a panel-like shape;

(D) applying to the top surface of said panel-like shape of slurry on overlying porous glass mat having an outer surface and a predetermined thickness;

(E) including in said slurry paper fibers in an amount such that portions of said slurry penetrate but part-way into the thickness of each of said underlying and overlying mats; and

(F) maintaining said panel-like shape as said calcined gypsum sets to form a set gypsum core having adhered thereto said mats, the outer surfaces of which are substantially free of set gypsum.