Acoustical sound proofing material with improved fracture characteristics and methods for manufacturing same

Abstract

A material for use in building construction (partition, wall, ceiling, floor or door) that exhibits improved acoustical sound proofing and fracture characteristics optimized for efficient installation. The material comprises a laminated structure having as an integral part thereof one or more layers of viscoelastic material which also functions both as a glue and as an energy dissipating layer; and one or more constraining layers, such as gypsum or cement-based panel products modified for easy fracture. In one embodiment, standard paper-faced wallboard, typically gypsum, comprises the external surfaces of the laminated structure with the inner surface of said wallboard being bare with no paper or other material being placed thereon. The resulting structure improves the attenuation of sound transmitted through the structure while also allowing installation of the sound proofing material as efficiently as the installation of standard material when the sound proofing material is used alone or incorporated into a partition assembly.

What is claimed is: 
     
         1 . A laminated, sound-attenuating structure, comprising:
 a first gypsum board having two surfaces, the two surfaces including a first outer faced surface and a first inner unfaced surface;   a layer of viscoelastic glue placed directly on the first inner unfaced surface; and   a second gypsum board located proximate to the layer of viscoelastic glue, the second gypsum board having two surfaces, the two surfaces including a second outer faced surface and a second inner unfaced surface.   
     
     
         2 . The structure of  claim 1 , wherein:
 at least one of the first inner unfaced surface and the second inner unfaced surface is substantially unfaced.   
     
     
         3 . The structure of  claim 1 , wherein:
 at least one of the first inner unfaced surface and the second inner unfaced surface is faced from a board edge to a determined distance from the board edge.   
     
     
         4 . The structure of  claim 3 , wherein:
 the determined distance is less than ¼ of a distance from the board edge to an opposite board edge.   
     
     
         5 . The structure of  claim 1 , wherein the second gypsum board directly contacts the layer of viscoelastic glue. 
     
     
         6 . The structure of  claim 1 , wherein the first outer faced surface is paper. 
     
     
         7 . The structure of  claim 1 , wherein the structure has a flexural strength of less than about 50 pounds force when one of the first or second outer faced surfaces has been scored. 
     
     
         8 . The structure of  claim 7 , wherein the structure has a flexural strength of about 22 pounds force when one of the first or second outer faced surfaces has been scored. 
     
     
         9 . A method of forming a laminated, sound-attenuating structure, comprising:
 forming a first gypsum board having two surfaces, the two surfaces including a first outer faced surface and a first inner unfaced surface;   placing a layer of viscoelastic glue directly on the first inner unfaced surface; and   placing a second gypsum board proximate to the layer of viscoelastic glue, the second gypsum board having two surfaces, the two surfaces including a second outer faced surface and a second inner unfaced surface.   
     
     
         10 . The method of  claim 9 , wherein:
 at least one of the first inner unfaced surface and the second inner unfaced surface is substantially unfaced.   
     
     
         11 . The method of  claim 9 , wherein:
 at least one of the first inner unfaced surface and the second inner unfaced surface is faced from a board edge to a determined distance from the board edge.   
     
     
         12 . The method of  claim 11 , wherein:
 the determined distance is less than ¼ of a distance from the board edge to an opposite board edge.   
     
     
         13 . The method of  claim 9 , wherein the second gypsum board directly contacts the layer of viscoelastic glue. 
     
     
         14 . The method of  claim 9 , wherein the first outer faced surface is paper. 
     
     
         15 . The method of  claim 9 , wherein the structure has a flexural strength of less than about 50 pounds force when one of the first or second outer faced surfaces has been scored. 
     
     
         16 . The method of  claim 15 , wherein the structure has a flexural strength of about 22 pounds force when one of the first or second outer faced surfaces has been scored. 
     
     
         17 . A laminated, sound-attenuating structure, comprising:
 a first gypsum board having two surfaces, the two surfaces including a first outer surface and a first inner surface;   a layer of viscoelastic glue placed directly on the first inner surface; and   a second gypsum board located proximate to the layer of viscoelastic glue, the second gypsum board having two surfaces, the two surfaces including a second outer surface and a second inner surface.   
     
     
         18 . The structure of  claim 17 , wherein:
 at least one of the first inner surface and the second inner is substantially unfaced.   
     
     
         19 . The structure of  claim 17 , wherein:
 at least one of the first inner surface and the second inner surface is faced from a board edge to a determined distance from the board edge.   
     
     
         20 . The structure of  claim 19 , wherein:
 the determined distance is less than ¼ of a distance from the board edge to an opposite board edge.   
     
     
         21 . The structure of  claim 17 , wherein the second gypsum board directly contacts the layer of viscoelastic glue. 
     
     
         22 . The structure of  claim 17 , wherein the first outer surface is faced with paper. 
     
     
         23 . The structure of  claim 17 , wherein the structure has a flexural strength of about 22 pounds force when one of the first or second outer faced surfaces has been scored. 
     
     
         24 . A method of forming a laminated, sound-attenuating structure, comprising:
 forming a first gypsum board having two surfaces, the two surfaces including a first outer surface and a first inner surface;   placing a layer of viscoelastic glue directly on the first inner surface; and   placing a second gypsum board proximate to the layer of viscoelastic glue, the second gypsum board having two surfaces, the two surfaces including a second outer surface and a second inner surface.   
     
     
         25 . The method of  claim 24 , wherein:
 at least one of the first inner surface and the second inner surface is substantially unfaced.   
     
     
         26 . The method of  claim 24 , wherein:
 at least one of the first inner surface and the second inner surface is faced from a board edge to a determined distance from the board edge.   
     
     
         27 . The method of  claim 26 , wherein:
 the determined distance is less than ¼ of a distance from the board edge to an opposite board edge.   
     
     
         28 . The method of  claim 24 , wherein the second gypsum board directly contacts the layer of viscoelastic glue. 
     
     
         29 . The method of  claim 24 , wherein the first outer surface is faced with paper. 
     
     
         30 . The method of  claim 24 , wherein the structure has a flexural strength of about 22 pounds force when one of the first or second outer faced surfaces has been scored.