Substrate with anti-soiling coating

1. A substrate having at least one main surface comprising a first coating deposited on said main surface and a second coating having anti-soiling properties deposited and adhering on the surface of said first coating,

the first coating being a (meth)acrylate based coating and being obtained by polymerizing a polymerizable composition comprising:

i) at least one (meth)acrylate compound and

ii) at least one compound I having at least one —M—Z′ bond with M representing Si or a Metal atom, Z′ representing OH or a hydrolysable group, and at least one ethylenic unsaturated group or epoxy group, and/or

iii) at least one silica or metal oxide colloid having free ethylenically unsaturated groups;

and

the second coating, having anti-soiling properties, being obtained by depositing on said first coating an anti-soiling coating composition comprising at least one compound II, or a hydrolyzate thereof, having at least one —Si—Z″ group with Z″ representing OH or a hydrolysable group.

2. A substrate according to claim 1 , wherein said polymerizable first coating composition comprises at least one metal alkoxide compound that do not contain any reactive unsaturated group.

3. A substrate according to claim 1 , wherein compound I is a colloidal silica having free acryloxy groups.

4. A substrate according to claim 3 , wherein compound II is a silane or a silazane bearing at least one group selected from fluorocarbons, polyfluorocarbons, fluoropolyethers and polyfluoropolyethers.

5. A substrate according to claim 1 , wherein said polymerizable first coating composition comprises from 2 to 50% by weight of compound I.

6. A substrate according to claim 1 , wherein said polymerizable first coating composition comprises from 10 to 40% by weight of compound I.

7. A substrate according to claim 1 , wherein the unsaturated group is a (meth)acryloxy group or a vinyl group.

8. A substrate according to claim 1 , wherein the second coating having anti-soiling properties is hydrophobic and/or oleophobic.

9. A substrate according to claim 1 , wherein compound II is a fluoro compound.

10. A substrate according to claim 1 , wherein compound II is a silane comprising polyfluoro polyether groups.

11. A substrate according to claim 1 , wherein compound II is represented by the general formula (I)

and has a number average molecular weight of from 5×10 2 to 1×10 5 wherein Rf represents perfluoroalkyl; Z represents fluoro or trifluoromethyl; a, b, c, d and e each independently represent 0 or an integer of 1 or above, provided that a+b+c+d+e is not less than 1 and the order of the repeating units parenthesized by subscripts a, b, c, d and e occurring in the formula is not limited to that shown; Y represents hydrogen or alkyl containing 1 to 4 carbon atoms; X represents hydrogen, bromo or iodo; R 1 represents hydroxy or a hydrolyzable substituent group; R 2 represents hydrogen or a monovalent hydrocarbon group; I represents 0, 1 or 2; m represents 1, 2 or 3; and n represents an integer of 1 or above, preferably 2 or above.

12. A substrate according to claim 1 , wherein the second coating having anti-soiling properties is deposited by dip coating or spin coating, preferably by dip coating.

13. A substrate according to claim 1 , wherein said polymerizable coating composition comprises:

i) at least one (meth)acrylate compound and

ii) at least one compound I having at least one —M—Z′ bond with M representing Si or a Metal atom, Z representing OH or a hydrolysable group, and at least one epoxy group, and optionally

iii) at least one silica or metal oxide colloid having free ethylenically unsaturated groups.

14. A substrate according to claim 1 , wherein said polymerizable first coating composition comprises:

i) at least one (meth)acrylate compound and

ii) at least one silica or metal oxide colloid having free ethylenically unsaturated groups and optionally

iii) at least one compound I having at least one —M—Z′ bond with M representing Si or a Metal atom, Z′ representing OH or a hydrolysable group, and at least one ethylenic unsaturated group or epoxy group.

15. A substrate according to claim 1 , wherein said at least one (meth)acrylate compound is selected from the group consisting of: allyl methacrylate; 2-ethoxyethyl acrylate; 2-ethoxyethyl methacrylate; caprolactone acrylate; isobornyl methacrylate; lauryl methacrylate; polypropylene glycol monomethacrylate; 1,4-butanediol diacrylate; 1,6-hexanediol diacrylate; 1,6-hexanediol dimethacrylate; polyethylene glycol diacrylate; tetraethylene glycol diacrylate; polyethylene glycol dimethacrylate; polyethylene glycol diacrylate; ethoxylated bisphenol A diacrylate; tetraethylene glycol diacrylate; tripropylene glycol diacrylate; neopentyl glycol diacrylate; 1,4-butanediol dimethacrylate; tetraethylene glycol dimethacrylate; diethylene glycol diacrylate; trimethylolpropane trimethacrylate; trimethylolpropane triacrylate; pentaerythritol triacrylate; ethoxylated trimethylolpropane triacrylate; trimethylolpropane trimethacrylate; dipentaerythritol pentaacrylate; pentaerythritol tetraacrylate; ethoxylated pentaerythritol tetraacrylate; and pentaacrylate ester.