SILANE-MODIFIED BINDER DISPERSIONS

1 . An aqueous formulation comprising

A) a silane-modified copolymer a1) and a polyorganosiloxane a2) containing hydroxyl groups;

B) optionally surface-modified inorganic particles having an average particle size (z-mean), as determined by means of dynamic light scattering in dispersion, of less than 200 nm; and

C) water.

2 . The aqueous formulation of claim 1 , wherein said silane-modified copolymer a1) comprises groups of general formula (1)

—Si(R 1 O) 2 R 2   (1)

wherein

R 1 is a C 2 - to C 8 -alkyl radical; and

R 2 is (R 1 O) or a C 1 - to C 5 -alkyl radical.

3 . The aqueous formulation of claim 1 , wherein said silane-modified copolymer a1) is a copolymer which is built up from

I) a hydroxy-functional hydrophobic polymer containing as builder monomers

Ia) (meth)acrylic acid esters having C 1 - to C 18 -hydrocarbon radicals in the alcohol part and/or vinylaromatics and/or vinyl esters;

Ib) hydroxy-functional monomers; and

IS1) silane-functional monomers capable of polymerization; and

II) a hydroxy-functional hydrophilic polymer containing as builder components

IIa) (meth)acrylic acid esters having C 1 - to C 18 -hydrocarbon radicals in the alcohol part and/or vinylaromatics and/or vinyl esters;

IIb) hydroxy-functional monomers; and

IIe) acid-functional monomers.

4 . The aqueous formulation of claim 1 , wherein said silane-modified copolymer a1) is a copolymer which is built up from

I) a hydroxy-functional hydrophobic polymer containing as builder monomers

Ia) (meth)acrylic acid esters having C 1 - to C 18 -hydrocarbon radicals in the alcohol part and/or vinylaromatics and/or vinyl esters; and

Ib) hydroxy-functional monomers; and

II) a hydroxy-functional hydrophilic polymer containing as builder components

IIa) (meth)acrylic acid esters having C 1 - to C 18 -hydrocarbon radicals in the alcohol part and/or vinylaromatics and/or vinyl esters;

IIb) hydroxy-functional monomers;

IIc) acid-functional monomers; and

IIS1) sitane-functional monomers capable of polymerization.

5 . The aqueous formulation of claim 3 , wherein said silane-functional monomer IS1), which is capable of polymerization, is a compound of the general formula (2)

(R 1 O) 2 R 2 Si—(CH═CH 2 )  (2)

wherein

R 1 is a C 2 - to C 8 -alkyl radical; and

R 2 is (R 1 O) or a C 1 - to C 5 -alkyl radical;

and/or a compound of the general formula (3)

(R 1 O) 2 R 2 Si(CH 2 ) m —O(CO)—(CR 3 CH 2 )  (3)

wherein

R 1 is a C 2 - to C 8 -alkyl radical;

R 2 is (R 1 O) or a C 1 - to C 5 -alkyl radical;

R 3 is H or CH 13 ; and

m is 1 to 4.

6 . The aqueous formulation of claim 4 , wherein said silane-functional monomer IIS1), which is capable of polymerization, is a compound of the general formula (2)

(R 1 O) 2 R 2 Si—(CH═CH 2 )  (2)

wherein

R 1 is a C 2 - to C 8 -alkyl radical; and

R 2 is (R 1 O) or a C 1 - to C 5 -alkyl radical;

and/or a compound of the general formula (3)

(R 1 O) 2 R 2 Si(CH 2 ) m —O(CO)—(CR 3 ═CH 2 )  (3)

wherein

R 1 is a C 2 - to C 8 -alkyl radical;

R 2 is (R 1 O) or a C 1 - to C 5 -alkyl radical;

R 3 is H or CH 3 ; and

m is 1 to 4.

7 . The aqueous formulation of claim 3 , wherein said silane-functional monomer IS1), which is capable of polymerization, is selected from the group consisting of vinyltriethoxysilane, vinyltrisisopropoxysilane, vinyl-tris-(2-methoxyethoxy)silane, vinylmethyldiethoxysilane, vinylmethyldiisopropoxysilane, vinylethyldiethoxysilane, 3-(triethoxysilyl)-propyl methacrylate or 3-(tris-isopropoxysilyl)-propyl methacrylate, vinylphenyldiethoxysilane, vinylphenylmethylethoxysilane or vinyltri-t-butoxysilane.

8 . The aqueous formulation of claim 4 , wherein said silane-functional monomer IIS1), which is capable of polymerization, is selected from the group consisting of vinyltriethoxysilane, vinyltrisisopropoxysilane, vinyl-tris-(2-methoxyethoxy)silane, vinylmethyldiethoxysilane, vinylmethyldiisopropoxysilane, vinylethyldiethoxysilane, 3-(triethoxysilyl)-propyl methacrylate or 3-(tris-isopropoxysilyl)-propyl methacrylate, vinylphenyldiethoxysilane, vinylphenylmethylethoxysilane or vinyltri-t-butoxysilane.

9 . The aqueous formulation of claim 1 , wherein said silane-modified copolymer a1) is a copolymer which is built up from

I) a hydroxy-functional hydrophobic polymer containing as builder monomers

Ia) (meth)acrylic acid esters having C 1 - to C 18 -hydrocarbon radicals in the alcohol part and/or vinylaromatics and/or vinyl esters; and

Ib) hydroxy-functional monomers; and

II) a hydroxy-functional hydrophilic polymer containing as builder components

IIa) (meth)acrylic acid esters having C 1 - to C 18 -hydrocarbon radicals in the alcohol part and/or vinylaromatics and/or vinyl esters;

IIb) hydroxy-functional monomers;

IIc) acid-functional monomers; and

IIS2) monomers which contain at least one epoxide function in addition to silane groups.

10 . The aqueous formulation of claim 9 , wherein said monomers IIS2) are selected from the group consisting of γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyl-tris-isopropoxysilane, γ-glycidoxypropyl-diethoxy-methylsilane, β-(3,4-epoxycyclohexyl)-triethoxysilane, and β-(3,4-epoxycyclohexyl)-tris-isopropoxysilane.

11 . The aqueous formulation of claim 1 , wherein said polyorganosiloxane a2) containing hydroxyl groups is a compound of the general formula (I)

wherein

X is an aliphatic, optionally branched C 1 to C 10 radical or

 a [—CH 2 —O—(CH 2 ) p —]Si unit, wherein r is an integer from 1 to 4;

R is a —CH(OH)Y group, wherein

Y is a —CH 2 —N(R 2 R 3 ) group, wherein

R 2 is H or a methyl, ethyl, n-propyl, iso-propyl, or cyclohexyl radical, or a 2-hydroxyethyl, 2-hydroxypropyl, or 3-hydroxypropyl radical; and

R 3 is a 2-hydroxyethyl, 2-hydroxypropyl, or 3-hydroxypropyl radical,

R 1 is, identically or differently, H or a C 1 - to C 10 -hydrocarbon radical optionally containing hetero atoms; and

n is an integer from 1 to 40.

12 . The aqueous formulation of claim 1 , wherein said polyorganosiloxane a2) containing hydroxyl groups is a compound of the general formula (V)

wherein

m is an integer from 5 to 15;

Z is H or methyl; and

n and o is an integer from 1 to 12.

13 . The aqueous formulation of claim 1 , wherein said polyorganosiloxane a2) containing hydroxyl groups is a compound of the general formula (VI)

wherein

m is an integer from 5 to 15; and

y is an integer from 2 to 4.

14 . The aqueous formulation of claim 11 , wherein said polyorganosiloxane a2) having the general formula (I) has a number-average molecular weight in the range of from 200 to 3,000 g/mol and an average OH functionality of at least 1.8.

15 . The aqueous formulation of claim 11 , wherein said polyorganosiloxane a2) having the general formula (I) has a number-average molecular weight in the range of from 250 to 2,250 g/mol.

16 . The aqueous formulation of claim 1 , wherein said inorganic particles B) are selected from the group consisting of inorganic oxides, mixed oxides, carbides, borides and nitrides of elements of main group II to IV and/or elements of subgroup I to VIII of the periodic table, including the lanthanides.

17 . The aqueous formulation of claim 1 , wherein said inorganic particles B) are inorganic nanoparticles in a colloidally disperse form in organic solvents or in water.

18 . The aqueous formulation of claim 1 , wherein said inorganic particles B) are inorganic particles in the form of aqueous formulations.

19 . The aqueous formulation of claim 1 , wherein said inorganic particles B) are surface-modified inorganic nanoparticles.

20 . An aqueous coating composition comprising the aqueous formulation of claim 1 and at least one crosslinking agent D).

21 . An aqueous two-component coating composition comprising the aqueous formulation of claim 1 and a polyisocyanate.

22 . A clear lacquer comprising the aqueous formulation of claim 1 .