Cement reinforced gypsum foam with mineral wool

• US 4,310,996 A
• Filed: 04/23/1980
• Issued: 01/19/1982
• Est. Priority Date: 04/23/1980
• Status: Expired due to Term

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: General Electric Company
• Inventors: Mulvey, Robert F., Crepeau, Charles E.
• Primary Examiner(s): Bell, J. Karl
• Application Number:
  US06/142,912
• Time in Patent Office: 636 Days
• Field of Search: 52/309.4, 52/404, 52/806, 52/809, 52/785, 52/612, 106/88, 106/111, 106/113, 156/42
• US Class Current: 52/794.1
• CPC Class Codes: E04B 1/80 slab-shaped
• CPC Class Codes: E04B 7/225 the slabs having non-structural supports for roofing materials

Abstract

An improved material particularly suited for the thermal insulation of building structures such as residential housing. The material comprises an inorganic, low-density cellular thermally insulating foam comprising a gypsum matrix having minute cavities homogeneously distributed therein. The material has a dry density of less than about 6 pounds per cubic foot and a thermal coefficient of less than about 0.37. The gypsum matrix includes therein approximately 1 to 15% by weight of cement, approximately 0.5 to 7% by weight of mineral wool and at least approximately 0.25% by weight of chopped glass.

Claims

1. A thermally insulating composite assembly, comprising generally at least one structural surface element and a low-density cellular gypsum material positioned adjacent to said surface element, said cellular gypsum material comprising a gypsum matrix having minute cavities homogeneously distributed therein, said gypsum material having a dry density of less than about 6 pounds per cubic foot and a thermal coefficient of less than about 0.37, said gypsum matrix including therein:

(a) approximately 1 to 15 percent by weight of a cement dispersed homogeneously throughout said gypsum matrix;

(b) approximately 0.5 to 7 percent by weight of a mineral wool dispersed homogeneously throughout said gypsum matrix; and

(c) at least approximately 0.25 percent by weight of a chopped glass distributed homogeneously throughout said gypsum matrix.

2. A composite assembly according to claim 1, wherein said gypsum material has a dry density of more than 0.8 pounds per cubic foot.

3. A composite assembly according to claim 1, further comprising at least first and second joists positioned adjacent to said one structural element for containing said gypsum material therebetween, and thereby to form a thermally insulating ceiling structure.

4. A composite assembly according to claim 1, further comprising a second structural element spaced parallel to said one structural element to hold said gypsum material therebetween, whereby to form a thermally insulating composite wall assembly.

5. A low-density cellular thermally insulating gypsum material comprising a gypsum matrix having minute cavities homogeneously distributed therein, said gypsum material having a dry density of less than about 6 pounds per cubic foot, and a thermal coefficient of less than about 0.37, said gypsum matrix including therein:

(a) approximately 1 to 15 percent by weight of a cement dispersed homogeneously throughout said gypsum matrix;

(b) approximately 0.5 to 7 percent by weight of a mineral wool dispersed homogeneously throughout said gypsum matrix; and

(c) at least approximately 0.25 percent by weight of a chopped glass distributed homogeneously throughout said gypsum matrix.

6. A low-density cellular thermally insulating gypsum material according to claim 5, wherein said gypsum material has a dry density of more than about 0.8 pounds per cubic foot.