Direct overmolding

1. Curable composition comprising

a) an epoxy resin

b) a filler composition comprising

i) wollastonite having an average particle size (d 50 ) from 2 to 50 μm and

ii) amorphous silica and

c) a polyester anhydride hardener obtained from the reaction of a dianhydride and a less equimoloar amount of a diol comprising polyethylene glycol

wherein at least one of the fillers of the filler composition is surface treated with a silane and the weight ratio of amorphous silica to wollastonite is from 10:1 to 1:10.

2. Curable composition according to claim 1 wherein the amorphous silica has an average particle size (d 50 ) ranging from 2 to 50 μm.

3. Curable composition according to claim 1 wherein the wollastonite and/or the amorphous silica is surface treated with a silane selected from the group consisting of aminosilane, epoxysilane, (meth)acrylic silane, methylsilane and vinylsilane.

4. Curable composition according to claim 1 wherein the amorphous silica is natural amorphous silica or fused silica.

5. A cured product obtained by curing the curable composition as defined in claim 1 .

6. Method for the manufacturing of a component of electrical insulation equipment comprising the steps:

a) applying a curable composition as defined in claim 1 to the housing of the electrical component; and

b) curing the curable composition.

7. Method according to claim 6 wherein the electrical component is selected from the group consisting of a transformer, a bushing, an insulator, a switch, a sensor, a converter and a cable end seal.

8. Method according to claim 6 wherein the electrical component is a switch gear.

9. Method according to claim 8 wherein the curable composition is directly applied to a ceramic housing of a vacuum chamber of the switch gear.