Multi-layer plasterboard

• US 3,993,822 A
• Filed: 03/16/1973
• Issued: 11/23/1976
• Est. Priority Date: 02/25/1970
• Status: Expired due to Term

• Current Assignee: Gebr. Knauf Westdeutsche Gipswerke
• Original Assignee: Gebr. Knauf Westdeutsche Gipswerke
• Inventors: Knauf, Karl, Altenhofer, Herbert, Neuhauser, Gerhard, Wirsching, Franz, Knauf, Alfons
• Primary Examiner(s): McCamish, Marion E.
• Assistant Examiner(s): Dixon, Jr., William R.
• Application Number:
  US05/341,955
• Time in Patent Office: 1,348 Days
• Field of Search: 161/88, 161/93, 161/156, 161/170, 161/192, 161/193, 161/37, 161/38, 161/39, 161/43, 161/45, 52/596, 428/247, 428/251, 428/252, 428/273, 428/213, 428/228, 428/268, 428/285, 428/299, 428/308, 428/317, 156/42, 156/71
• US Class Current: 428/213
• CPC Class Codes: B28B 19/0092 to webs, sheets or the like, e.g. of paper, cardboard
• CPC Class Codes: B32B 13/14 next to a fibrous or filamentary layer
• CPC Class Codes: B32B 2262/101 Glass fibres
• CPC Class Codes: B32B 2315/18 Plaster
• CPC Class Codes: E04C 2/043 of plaster E04C2/049 takes precedence
• CPC Class Codes: Y10T 428/2495 Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/249968 Of hydraulic-setting material
• CPC Class Codes: Y10T 428/249986 Void-containing component contains also a solid fiber or solid particle
• CPC Class Codes: Y10T 442/3797 Coating or impregnation is derived from a water-settable material [e.g., cement, gypsum, etc.]

Abstract

A multi-layered gypsum board for construction purposes in which a mixture of gypsum, water and fibers provide the center or core of the board, and a composite coating of a fiberglass layer and a layer of fiberglass fleece covers one of the major surfaces of the core, with the fiberglass layer being embedded into the mixture and plaster favorably adhering to the outer surface of the fiberglass fleece layer. The other major surface of the core may be covered with a similar coating, or a layer, for example, of pasteboard.

Claims

1. A multi-layered gypsum board for construction purposes including a plate-like core of a soft, watery paste-like mixture of gypsum, water and fibers, the core having opposite major surfaces, one major surface being covered with a layer for preventing the penetration of plaster and the other major surface being covered with two layers, one layer being a cloth and the other layer being a material which is denser than the cloth of the one layer for preventing the penetration of gypsum, said two layers being adhesively bonded to each other for providing a composite deposited in a gypsum-free dry condition on the core, one of the two layers being embedded in the core and the other layer being free of gypsum, the thickness of the combined two layers being smaller than the thickness of the core and the core after being covered on the major surfaces with the layers being allowed to harden, the improvement being that the cloth layer is embedded in the core and is fiberglass while the material of the other layer which is denser than the cloth layer is a glassfiber fleece preventing the penetration of gypsum and on the outer surface of which plaster will favorably adhere.

2. The multi-layered gypsum board as claimed in claim 1 in which said fiberglass cloth has a mesh density of 0.5/cm to about 10/cm.