Aircraft Transparency
A hybrid polymeric aircraft transparency is disclosed. The transparency, e.g., window, is easier to maintain because scratches can be polished out of the surface. Further, the transparency is lighter in weight and relatively tough because it is constructed of polycarbonate layers instead of acrylics. The transparency is constructed using injection-compression-molding techniques.
1 . An aviation transparency comprising:
a base layer including a polycarbonate polymer;
an upper layer including an acrylic polymer; and
an intermediate layer including a polymeric material for confining defects to the base layer and the upper layer, the intermediate layer between the base layer and the outer layer.
2 . The aviation transparency of claim 1 including an aircraft window.
3 . The aviation transparency of claim 1 wherein said polycarbonate polymer is an optical grade polycarbonate.
4 . The aviation transparency of claim 1 wherein said acrylic polymer is Polymethyl Methacrylate (methyl 2-methylpropenoate) (PMMA).
5 . The aviation transparency of claim 1 wherein said intermediate layer is Polyvinyl butyral resin (PVB).
6 . An aviation transparency comprising:
a polycarbonate polymer central layer;
a first acrylic polymer layer adhered to one side of said central layer; and
a second acrylic polymer layer adhered to another side of said central layer.
7 . The aviation transparency of claim 6 wherein said first acrylic layer is adhered to said central layer using a first intermediate layer of polymeric material and said second acrylic layer is adhered to said central layer using a second intermediate layer of polymeric material.
8 . A method of making an aircraft transparency, said method comprising:
injection compression molding a polycarbonate base layer;
injection compression molding an acrylic outer layer such that said outer layer nests with said base layer;
adhering said base and outer layers to one another using an optically-clear adhesion promoter to form an assembly; and
curing said assembly.