Patent ID: 8552083

Claim:
A cross-linking agent which is particularly useful in making optically clear low refractive index coatings having a structural formula selected from the group consisting of: and wherein R represents a hydrogen atom or a methyl group, wherein m represents an integer of 2 or higher, wherein n represents an integer of 2 or higher, wherein x represents an integer of greater than 0 and wherein the —(CF 2 CF 2 O)— repeat units and the —(CF 2 O)— repeat units can be distributed in any order, wherein R represents a hydrogen atom or a methyl group, wherein m represents an integer of 2 or higher, wherein n represents an integer of 2 or higher, and wherein ˜ indicates that the —(CF 2 CF 2 O)— repeat units and the —(CF 2 O)— repeat units can be distributed in any order.