Pigmented alkoxyzirconium sol

A graded mixed metal Zr:Si sol-gel, comprising:

• (a) a first layer made by mixing in a suitable carrier an effective amount of an organozirconium with TEOS to form a sol-gel network;
• and
• (b) a second layer made by mixing in a suitable carrier an effective amount of the organozirconium and an organosilane selected from the group consisting of:
• 3-aminopropyltriethoxysilane,
• 3-glycidoxypropyltrimethoxysilane,
• p-aminophenyltrimethoxysilane,
• m-aminophenyltrimethoxysilane,
• allyltrimethoxysilane,
• n-(2-aminoethyl)-3-aminopropyltrimethoxysilane,
• 3-aminopropyltrimethoxysilane,
• 3-glycidoxypropyldiisopropylethoxysilane,
• (3-glycidoxypropyl)methyldiethoxysilane
• 3-glycidoxypropyltrimethoxysilane,
• 3-mercaptopropyltrimethoxysilane,
• 3-mercaptopropyltriethoxysilane,
• 3-methacryloxypropylmethyldiethoxysilane,
• 3-methacryloxypropylmethyldimethoxysilane,
• 3-methacryloxypropyltrimethoxysilane,
• n-phenylaminopropyltrimethoxysilane,
• vinylmethyldiethoxysilane,
• vinyltriethoxysilane,
• vinyltrimethoxysilane, and mixtures thereof
• to form a sol-gel network, wherein the first layer has a stronger ceramic character than the second layer.

A sol suitable for surface treatment of a substrate to provide a high temperature sol gel coating, made by mixing in a suitable carrier:

• a) an effective amount of tetra-propoxyzirconium (TPOZ) for covalently bonding to the substrate;
• b) an effective amount of an organosilane coupling agent for forming a sol-gel network with the TPOZ;
• c) an organic acid to catalyze the networking of the organosilane to the TPOZ and to stabilize the rate of hydrolysis of the TPOZ;
• d) an effective amount of a pigment to control gloss, color, reflectivity, electrical conductivity, emissivity, or a combination thereof of the substrate when coated with the sol to form the sol-gel as a thin film finish, the pigment including metal, carbon, graphite, or a combination thereof;
• and
• e) an effective amount of aminopropyltrimethoxysilane as a dispersant.