Method of coating an inorganic substrate with a stable organic layer
A method for coating a metallic or inorganic substrate is described, such as metal or glass supports, with an organic layer comprising conjugated diene phosphinate or phosphonate compounds.
1. A method of coating at least one surface of an inorganic substrate with an organic coating, the method comprising the following steps:
(a) treating the at least one surface of the substrate by contacting said surface with a composition consisting of a solvent and at least one compound having the following formula (I):
wherein,
each of R 1 , R 2 , R 3 , R 4 , and R 5 , which can be identical or different, and is selected from hydrogen, an alkyl, an aryl, an alkaryl, an aralkyl, a cycloalkyl, a heterocycloalkyl, or an alkenyl group;
R 6 is selected from H, an alkyl, an aryl, an alkaryl, an aralkyl, a cycloalkyl, a heterocycloalkyl,
an alkenyl group, or an —OR 8 group, wherein R 8 is selected from a hydrogen, an alkyl, an aryl, an alkaryl, an aralkyl, a cycloalkyl, a heterocycloalkyl, an alkenyl group, or a metal selected from the group consisting of Na, Li, and Ca, or an ammonium compound;
R 7 is selected from a hydrogen, an alkyl, an aryl, an alkaryl, an aralkyl, a cycloalkyl, or an alkenyl group, or a metal selected from the group consisting of Na, Li, and Ca, or an ammonium compound;
whereby the at least one compound of formula (I) adsorbs on said surface; and
(b) submitting the surface of the substrate modified in the treatment of step (a) to heat or UV irradiation;
whereby the at least one compound of formula (I) reacts and forms a stable coating on said surface.
2. The method as defined by claim 1 , wherein R 1 , R 2 and R 4 are hydrogen; R 3 and R 5 are methyl; and R 7 is hydrogen.
3. The method as defined by claim 1 , wherein R 6 is hydrogen.
4. The method as defined by claim 1 , wherein R 8 is hydrogen.
5. The method as defined by claim 1 , wherein the compound of formula (I) is a conjugated diene phosphinate.
6. The method as defined by claim 1 , wherein the compound of formula (I) is a conjugated diene phosphonate compound having the following formula:
7. The method as defined by claim 1 , wherein the method further comprises a preliminary treatment of the substrate before step (a).
8. The method as defined by claim 7 , wherein the preliminary treatment comprises oxidation of the surface of the substrate.
9. The method as defined by claim 1 , wherein the method further comprises washing of the substrate after step (b).
10. The method as defined by claim 9 , wherein the substrate is washed with acetone.
11. The method as defined by claim 1 , wherein the substrate comprises steel, aluminium, an alloy thereof, or an oxide thereof.
12. The method as defined by claim 1 , wherein the substrate is glass or tin oxide.
13. The method as defined by claim 1 , wherein the method protects the substrate against corrosion.
14. The method as defined by claim 1 , wherein the method modifies wettability and/or hydrophobicity of the substrate.
15. The method as defined by claim 1 , wherein the method improves paintability of the substrate.