Composite interlayer for laminated glass
View Patent ↗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 multilayer composite suitable for use in glass laminates, said process comprising:
coextruding a first layer comprising a plasticized polyvinyl butyral and a second layer adjacent to said first layer comprising polyurethane under conditions wherein plasticizer can migrate from said polyvinyl butyral to said polyurethane.
2. The process of claim 1 wherein the polyurethane layer has a thickness of less than 5 mils.
3. The process of claim 1 further comprising coextruding a third layer comprising polyurethane on a side of the polyvinyl butyral layer opposite the second layer.
4. The process of claim 3 wherein the second and third polyurethane layers each have a thickness of less than 5 mils.