Polymeric anti-reflection coatings and coated articles

DETAILED DESCRIPTION This invention provides devices comprising a reflective substrate having deposited thereon as an anti-reflection coating a thin film of copolymer of fluorine-containing acrylic monomers with non-fluorinated acrylic monomers.
Such copolymer can be made under free-radical polymerization conditions.
These copolymers are amorphous and optically clear, and have low refractive indexes.
Being soluble in specific organic solvents, their solutions can be used to cast anti-reflection coatings, which can be cured by cross-linking.
These coatings are strongly adherent to substrates, including glass, polymers, polymer films and crystal substrates.
These copolymer anti-reflection coatings combine the superior properties of fluoropolymers--such as low refractive index and surface energy, good thermal and chemical resistance--with strong adhesion, flexibility, toughness, and abrasion resistance.
Moreover, they can be easily applied from solution, and they are readily cured by cross-linking.
They are suitable for application to very large area substrates at relatively low cost.
In accordance with the present invention, there are provided devices comprising a reflective substrate having deposited thereon as an anti-reflection coating an effective layer of a polymeric composition comprising fluorinated copolymer having the general composition ##STR1## wherein R.
sup.
1 is H, --CH.
sub.
3, or mixtures thereof; R.
sup.
2 is H, --CH.
sub.
3, or --CH.
sub.
2 COOH; R.
sup.
3 is H, --Ch.
sub.
3, or --CH.
sub.
2 COOC.
sub.
m H.
sub.
2m+1, wherein m is an integer of from about 1 to about 4; R.
sup.
4 is an alkylene bridging group, straight chain, branched or cyclic, having from 1 to about 8 carbon atoms; p is 1 or 2; s, t and u represent weight proportions of the respective monomer-derived units, and have values within the ranges of s=from about 0.
5 to about 0.
99; t=from about 0.
005 to about 0.
495; and u =from about 0.
005 to about 0.
495; with the sum of s+t+u being 1; and n is an integer of from about 1 to about 40; wherein the monomer-derived units may be arranged in any sequence