I/We Claim:
1. A protective coating on a substrate, the coating comprising:
a. a primer comprising an epoxy ester resin, a solid epoxy, and a modified
melamine crosslinker; and
5 b. a top-coat comprising a thermosetting acrylic resin, and a modified
melamine crosslinker,
wherein the modified melamine crosslinker is selected from C1-3 alkyl
substituted melamine formaldehyde.
2. The coating as claimed in claim 1, wherein the epoxy ester resin is in a weight
10 range of 15 to 70%, with respect to total weight of the primer; the solid epoxy
is in a weight range of 5 to 30%, with respect to total weight of the primer;
and the modified melamine crosslinker is in a weight range of 4 to 30%, with
respect to total weight of the primer.
3. The coating as claimed in claim 1, wherein the thermosetting acrylic resin is
15 in a weight range of 30 to 85%, with respect to total weight of the top-coat;
and the modified melamine crosslinker is in a weight range of 5 to 30%, with
respect to total weight of the top-coat.
4. The coating as claimed in claim 1, wherein the epoxy ester resin has a
molecular weight in a range of 6000 to 7000 g/mol, an acid value in a range
20 of 4 to 6 and a hydroxy functionalisation in a range of 130 to 150%; and the
solid epoxy has an epoxy equivalent weight in a range of 250 to 700.
5. The coating as claimed in claim 1, wherein the epoxy ester resin is a fatty acid
ester; and the solid epoxy is a bisphenol A based epoxy.
6. The coating as claimed in claim 1, wherein the ratio of combined weight of
25 the epoxy ester resin and the solid epoxy to the weight of modified melamine
crosslinker is in a range of 8.5:1.5 to 7.5:2.5; and the ratio of the thermosetting
24
acrylic resin and the modified melamine crosslinker is in a range of 7: 3 to 8:
2.
7. The coating as claimed in claim 1, wherein the thermosetting acrylic resin has
hydroxy functionalisation in a range of 50 to 100 % and is a styrenated acrylic.
5 8. The coating as c