Two-layer antireflective coating applied in solution

An allyl diglycol carbonate polymer or glass substrate having a two-layer antireflective coating composition comprising a bottom layer containing between 0.28 and 10% by weight of titanium dioxide and a polysiloxane resin and a titanium-free top layer containing a polysiloxane resin;

• wherein the refractive indices of said coating layers satisfy the following requirements:
• n.sub.s <n.sub.b >n.sub.t
• where n.sub.s represents the refractive index of said substrate, n.sub.b represents the refractive index of said bottom layer, and n.sub.t represents the refractive index of said top layer.

A process for preparing a two-layer antireflective coating on an allyl diglycol carbonate polymer or glass substrate comprising the steps of:

• (d) etching said substrate with a caustic solution comprising at least one fluorosurfactant in an effective amount;
• (b) applying a bottom layer to said substrate, and curing said bottom layer to obtain a layer comprising between 0.28 and 10% by weight of titanium dioxide and polysiloxane resin;
• (c) applying a top layer to said cured bottom layer, the top layer being titanium-free and comprising polysiloxane resins, and curing said top layer.