Alkyd-based coating composition

1. A coating composition comprising:

a) silanized colloidal silica particles having an average particle diameter ranging from 2 to 150 nm and a weight ratio of silane to silica ranging from 0.05 to 0.4,

b) an alkyd-containing binder and, optionally, an other binder,

c) a carrier fluid selected from water and/or an organic solvent, and

d) optionally, a cobalt based drier,

wherein the cobalt based drier, if present, has a cobalt content of less than 200 ppm based on the total weight of binder, and wherein the alkyd-containing binder is selected from epoxy-modified or polyurethane-modified alkyds.

2. The composition according to claim 1 , wherein the composition contains cobalt in an amount less than 100 ppm based on the total weight of binder.

3. The composition according to claim 1 , wherein no cobalt drier is present in the coating composition.

4. The composition according to claim 1 , wherein the colloidal silica particles have an average particle diameter ranging from about 6 to about 12 nm.

5. The composition according to claim 1 , wherein the weight ratio of silanized colloidal silica particles to total amount of binder ranges from about 0.05 to about 2.

6. The composition according to claim 1 , wherein the composition is an aqueous dispersion.

7. The composition according to claim 1 , wherein the silanized colloidal silica particles are present in the composition in an amount from about 2 to about 25 wt % based on the carrier fluid free weight of the composition.

8. A method of producing a coating composition comprising mixing

a) silanized colloidal silica particles having an average particle diameter ranging from 2 to 150 nm and a weight ratio of silane to silica of 0.05 to 0.4; and

b) an alkyd-containing binder and, optionally, an other binder; and

c) a carrier fluid selected from water and/or an organic solvent; and

d) optionally, a cobalt based drier,

wherein the cobalt based drier, if present, has a cobalt content of less than 200 ppm based on the total weight of binder in the coating composition, and wherein the alkyd-containing binder is selected from epoxy-modified or polyurethane-modified alkyds.

9. The method according to claim 8 , wherein no cobalt-based drier is added to the coating composition.

10. The method according to claim 8 , wherein the silanized colloidal silica particles and alkyd-containing binder or total amount of binder are added in a weight ratio of silanized silica to binder ranging from about 0.05 to about 2.

11. A method of coating a substrate comprising coating a substrate with the coating composition according to claim 1 .