Composite Interlayer For Laminated Glass
A composite interlayer suitable for using laminated glass includes a layer of plasticized polyvinyl butyral sandwiched between second and third polymeric layers. In a preferred embodiment, at least one and preferably both of the second and third layers are less than 5 mils thick and formed of polyurethane.
1 . A process for forming a laminate, said process comprising:
coextruding a plasticized polyvinyl butyral layer, a first polyurethane layer, and a second polyurethane layer to form a composite interlayer, wherein said polyvinyl butyral layer is between said first polyurethane layer and said second polyurethane layer; and,
laminating said composite interlayer between two rigid substrates to form said laminate.
2 . The process of claim 1 , wherein at least one of said first polyurethane layer and said second polyurethane layer has a thickness of less than 5 mils.
3 . The process of claim 1 , wherein both of said first polyurethane layer and said second polyurethane layer have a thickness of less than 5 mils.
4 . The process of claim 1 , wherein said rigid substrates comprise glass.
5 . The process of claim 1 , wherein said rigid substrates comprise rigid plastic glazing panels.
6 . The process of claim 1 , wherein said first polyurethane layer and said second polyurethane layer are plasticized by migration of plasticizer from said plasticized polyvinyl butyral layer after the layers are combined.
7 . The process of claim 1 , wherein one of said first polyurethane layer and said second polyurethane layer comprises an aliphatic isocyanate-polyether urethane.
8 . The process of claim 1 , wherein one of said first polyurethane layer and said second polyurethane layer comprises an aliphatic isocyanate-polyester urethane.
9 . The process of claim 1 , wherein both of said first polyurethane layer and said second polyurethane layer comprise an aliphatic isocyanate-polyester urethane.
10 . The process of claim 1 , wherein both of said first polyurethane layer and said second polyurethane layer comprise an aliphatic isocyanate-polyether urethane.
11 . A laminated glass panel produced by the process comprising the steps of: coextruding a plasticized polyvinyl butyral layer, a first polyurethane layer, and a second polyurethane layer to form a composite interlayer, wherein said polyvinyl butyral layer is between said first polyurethane layer and said second polyurethane layer; and, laminating said composite interlayer between two rigid substrates to form said laminate.
12 . The panel of claim 11 , wherein at least one of said first polyurethane layer and said second polyurethane layer has a thickness of less than 5 mils.
13 . The panel of claim 11 , wherein both of said first polyurethane layer and said second polyurethane layer have a thickness of less than 5 mils.
14 . The panel of claim 11 , wherein said rigid substrates comprise glass.
15 . The panel of claim 11 , wherein said rigid substrates comprise rigid plastic glazing panels.
16 . The panel of claim 11 , wherein said first polyurethane layer and said second polyurethane layer are plasticized by migration of plasticizer from said plasticized polyvinyl butyral layer after the layers are combined.
17 . The panel of claim 11 , wherein one of said first polyurethane layer and said second polyurethane layer comprises an aliphatic isocyanate-polyether urethane.
18 . The panel of claim 11 , wherein one of said first polyurethane layer and said second polyurethane layer comprises an aliphatic isocyanate-polyester urethane.
19 . The panel of claim 11 , wherein both of said first polyurethane layer and said second polyurethane layer comprise an aliphatic isocyanate-polyester urethane.
20 . The panel of claim 11 , wherein both of said first polyurethane layer and said second polyurethane layer comprise an aliphatic isocyanate-polyether urethane.