Intrusion resistant glass laminates

Abstract

Composite laminate interlayers for adhering a glass laminate comprising a sheet of polyethylene terephthalate (PET) between layers of plasticized polyvinyl butyral (PVB) adhesive layers, wherein at least one of the PVB adhesive layers is stiffened, e.g. by reduction in the amount of plasticizer, and has a glass transition temperature greater than 35° C. The PET is preferably 0.075 to 0.25 mm (3-10 mils) thick and can have a functional coating for reducing radiation, e.g. UV or IR or visible light, transmission through the glass laminate. The laminate can also comprise at least one elastomeric layer adapted to reducing sound transmission through the glass laminate. The laminates exhibit enhanced maximum flexural modulus of greater than about 350 Newtons/centimeter.

1 . A composite laminate interlayer for adhering a glass laminate consisting essentially of a sheet of polyethylene terephthalate between two layers of plasticized polyvinyl butyral adhesive layers, wherein both layers of plasticized polyvinyl butyral have a thickness in the range of 0.25 to 2 millimeters (10-80 mils) and wherein at least one of said polyvinyl butyral adhesive layers has a glass transition temperature greater than 35° C. and a tensile modulus at 25° C. of greater than about 10 7  Pa.  
     
     
         2 . An interlayer according to  claim 1  wherein said polyvinyl butyral adhesive layers are of different thickness.  
     
     
         3 . An interlayer according to  claim 1  wherein said polyethylene terephthalate sheet has a thickness greater than 0.075 millimeters (3 mils).  
     
     
         4 . An interlayer according to  claim 1  wherein said polyethylene terephthalate sheet has a thickness greater than 0.1 millimeters (4 mils).  
     
     
         5 . An interlayer according to  claim 1  wherein said sheet of polyethylene terephthalate has a functional coating for reducing radiation transmission through said glass laminate.  
     
     
         6 . A composite laminate interlayer for adhering glass laminates consisting essentially of a layer of polyethylene terephthalate between two layers of plasticized polyvinyl butyral adhesive layers, wherein the polyethylene terephthalate layer has a thickness in the range of 0.125 to 0.254 millimeters (5-10 mils); and each adhesive layer has a thickness in the range of 0.25 to 2 millimeter (10-80 mils) and wherein at least one layer of plasticized polyvinyl butyral has a glass transition temperature greater than 35° C. and a tensile modulus at 25° C. of greater than about 10 7  Pa.  
     
     
         7 . A glass laminate having improved stiffness comprising in order: 
 (a) a first glass sheet,    (b) a first layer of plasticized polyvinyl butyral adhesive having a thickness in the range of 0.25 to 2 millimeters (10-80 mils),    (c) a sheet of polyethylene terephthalate greater than 0.075 millimeters (3 mils) thick,    (d) a second layer of plasticized polyvinyl butyral adhesive having a thickness in the range of 0.25 to 2 millimeter (10-80 mils), and    (e) a second glass sheet,    wherein said glass laminate exhibits a maximum flexural modulus of greater than about 350 Newtons/centimeter, and    wherein at least one of the layers of plasticized polyvinyl butyral has a glass transition temperature greater than 35° C. and a tensile modulus at 25° C. of greater than about 10 7  Pa.    
     
     
         8 . A glass laminate according to  claim 7  exhibiting a maximum load before failure of at least 3000 Newtons.  
     
     
         9 . A glass laminate according to  claim 7  wherein at least one of the layers of plasticized polyvinyl butyral has a glass transition temperature greater than 40° C.  
     
     
         10 . A glass laminate according to  claim 7  wherein said sheet of polyethylene terephthalate has a radiation blocking coating.  
     
     
         11 . A glass laminate having improved stiffness consisting essentially of in order: 
 (a) a first glass layer,    (b) a first layer of plasticized polyvinyl butyral adhesive having a thickness in the range of 0.25 to 2 millimeters (10-80 mils),    (c) a layer of polyethylene terephthalate,    (d) a second layer of plasticized polyvinyl butyral adhesive having a thickness in the range of 0.25 to 2 millimeters (10-80 mils),    (e) a second glass layer,    wherein at least one layer of plasticized polyvinyl butyral adhesive has a glass transition temperature greater than 35° C. and a tensile modulus at 25° C. of greater than about 10 7  Pa.    
     
     
         12 . A glass laminate according to  claim 11  wherein said glass laminate exhibits a maximum flexural modulus greater than about 350 Newtons/centimeter.  
     
     
         13 . A glass laminate according to  claim 11  wherein said glass laminate exhibits a maximum flexural modulus greater than about 450 Newtons/centimeter.  
     
     
         14 . A glass laminate according to  claim 11  wherein said glass laminate exhibits a maximum flexural modulus greater than about 550 Newtons/centimeter.  
     
     
         15 . A glass laminate according to  claim 11  wherein said glass laminate exhibits a maximum flexural modulus greater than about 650 Newtons/centimeter.  
     
     
         16 . A glass laminate according to  claim 11  exhibiting a maximum load before failure from a secured frame of at least 3000 Newtons.  
     
     
         17 . A glass laminate according to  claim 11  exhibiting a maximum load before failure from a secured frame of at least 4000 Newtons.  
     
     
         18 . A glass laminate according to  claim 11  exhibiting a maximum load before failure from a secured frame of at least 5000 Newtons.  
     
     
         19 . A glass laminate according to  claim 11  exhibiting a maximum load before failure from a secured frame of at least 6000 Newtons.  
     
     
         20 . A glass laminate according to  claim 11  wherein said sheet of polyethylene terephthalate has a radiation blocking coating.