Stiff interlayers for laminated glass structures

Abstract

A new laminated glass structure for automotive glazing, architectural window and other applications that includes two sheets of relatively thin, optionally chemically strengthened glass, such as Corning® Gorilla® Glass, with a composite interlayer structure that includes at least one relatively stiff layer having relatively high Young's modulus of 50 MPa or higher and a relatively softer polymer layer having a relatively low Young's modulus of 20 MPa or lower.

What is claimed is: 
     
         1 . A glass laminate comprising:
 a first chemically strengthened alkali aluminosilicate glass sheet having a thickness of 1.5 mm or less;   a second glass sheet; and   a composite interlayer positioned between the first and second glass sheets, the composite interlayer comprising:
 two relatively stiff polymer layers having a Young's modulus of 50 MPa or greater, and selected from the group consisting of polyvinyl butyral (PVB), polycarbonate (PC), or polyethylene terephthalate (PET), and 
 a relatively soft polymer layer having a Young's modulus of less than 20 MPa, and selected from the group consisting of polyvinyl butyral (PVB), acoustic polyvinyl butyral (A-PVB), ethylene vinyl acetate (EVA), plasticized polyvinyl chloride (PVC), or thermoplastic polyurethane (TPU), 
 wherein the relatively soft polymer layer is disposed between the two relatively stiff polymer layers. 
   
     
     
         2 . The glass laminate of  claim 1 , wherein the two relatively stiff polymer layers have a Young's modulus of 100 MPa or greater. 
     
     
         3 . The glass laminate of  claim 1 , wherein the two relatively stiff polymer layers have a Young's modulus ranging from 100 MPa to 1000 MPa. 
     
     
         4 . The glass laminate of  claim 1 , wherein the relatively soft polymer layer has a Young's modulus of 10 MPa or less. 
     
     
         5 . The glass laminate of  claim 1 , wherein the relatively soft polymer layer has a Young's modulus ranging from 1 MPa to 10 MPa. 
     
     
         6 . The glass laminate of  claim 1 , wherein the two relatively stiff polymer layers have a Young's modulus 10-100 times greater than the Young's modulus of the relatively soft polymer layer. 
     
     
         7 . The glass laminate of  claim 1 , wherein the composite interlayer makes up a majority of a total thickness of the glass laminate. 
     
     
         8 . The glass laminate of  claim 7 , wherein the composite interlayer makes up at least 57% of the total thickness of the glass laminate. 
     
     
         9 . The glass laminate of  claim 7 , wherein at least one of the first or second glass sheets has a thickness ranging from 0.5 mm to 1.5 mm. 
     
     
         10 . The glass laminate of  claim 1  comprising a total thickness of from about 2 mm to about 4 mm. 
     
     
         11 . The glass laminate of  claim 1 , wherein the second glass sheet is chemically strengthened. 
     
     
         12 . The glass laminate of  claim 1 , wherein the second glass sheet is non-chemically-strengthened. 
     
     
         13 . The glass laminate of  claim 1 , wherein the first chemically strengthened alkali aluminosilicate glass sheet comprises from 8 mol% to about 18 mol% Na 2 O. 
     
     
         14 . The glass laminate of  claim 1 , wherein the first chemically strengthened alkali aluminosilicate glass sheet comprises from 9 mol% to about 21 mol% Na 2 O. 
     
     
         15 . The glass laminate of  claim 1 , wherein the first chemically strengthened alkali aluminosilicate glass sheet is an alkali aluminoborosilicate glass.