Zinc rich epoxy coating
The present disclosure relates to a coating composition, comprising: —a resin component containing an epoxy resin and a petroleum resin; —zinc particles in an amount of at least 65 wt.-%, based on the total solid weight of the coating composition; —a metallic salt of phosphorous acid; and —a hardener. In addition, the present disclosure also relates to a multi-part coating form of said coating composition, a method for preparing the coating composition and a substrate coated with the coating composition.
1 . A coating composition, comprising:
a resin component comprising an epoxy resin and a petroleum resin;
zinc particles in an amount of at least 75 wt.-%, based on the total solid weight of the coating composition;
a metallic salt of phosphorous acid; and
a hardener,
wherein the weight ratio of the metallic salt of phosphorous acid to zinc particles is 1:25 to 1:45.
2 . The coating composition according to claim 1 , wherein the coating composition contains at least 70 wt.-%, of zinc particles.
3 . The coating composition according to claim 1 , wherein the amount of the petroleum resin is greater than 0 up to 10 wt.-%, based on the total weight of the coating composition.
4 . The coating composition according to claim 1 , wherein the weight ratio of said epoxy resin to said petroleum resin is in a range of 2-10:1.
5 . The coating composition according to claim 1 , wherein the metallic salt of phosphorous acid comprises phosphate, phosphite, hypophosphite, hydrogen phosphate, dihydrogen phosphate, hydrogen phosphite, dihydrogen phosphite and polyphosphate, phosphates or polyphosphates modified with silicon, or mixtures thereof.
6 . The coating composition according to claim 1 , wherein the amount of said epoxy resin is 3 to 25 wt.-% based on the total weight of the coating composition, and/or the epoxy equivalent is 100 to 2,000 g/eqv.
7 . The coating composition according to claim 1 , wherein said epoxy resin includes both liquid type epoxy resin and solid type epoxy resin.
8 . The coating composition according to claim 7 , wherein the amount of said liquid type epoxy resin is 0.5 to 15 wt.-% and the amount of said solid type epoxy resin is 1 to 20 wt.-% based on total weight of the coating composition.
9 . The coating composition according to claim 1 , wherein the hardener comprises polyamine, primary or secondary diamines or polyamines, wherein the groups linked to a nitrogen atom may be saturated or unsaturated aliphatics, alicyclics, aromatics, aromatic substituted aliphatics, aliphatic substituted aromatics, heterocyclics, or mixtures thereof.
10 . The coating composition according to claim 1 , further comprising glass microspheres in an amount of 1 to 5 wt.-%, based on the total weight of the composition.
11 . The coating composition of claim 1 , wherein the epoxy resin is saturated or unsaturated, cyclic or acyclic, aliphatic, alicyclic, aromatic or heterocyclic, unsubstituted or substituted, or mixtures thereof.
12 . The coating composition of claim 1 , wherein the petroleum resin comprises an aliphatic or cycloaliphatic resin based on C5 or cycloaliphatic dienes, aromatic components based on C9, hydrogenated products, or mixtures thereof.
13 . The coating composition claim 1 , wherein the zinc particles are at least 94% pure, have an average particle size from 1 to 150 μm, are present in the coating composition in an amount of no more than 95 wt % based on the total weight of the composition, and/or are surface treated.
14 . The coating composition of claim 1 , wherein the composition comprises 5 wt % or less of metal particles other than zinc.
15 . The coating composition of claim 1 , wherein the metallic salt of phosphorus acid does not comprise an alkaline metal salt.
16 . The coating composition of claim 1 , further comprising a hardening promoter, a solvent, a thixotropic agent, a wetting and dispersing agent, a filler, a pigment, or mixtures thereof.
17 . A substrate coated with the coating composition of claim 1 .
18 . The substrate of claim 17 , wherein the substrate comprises iron, steel, and/or aluminum and/or alloys thereof.
19 . The substrate of claim 17 , wherein the substrate comprises part of a vehicle.
20 . A coating composition, comprising:
a resin component comprising an epoxy resin and a petroleum resin;
zinc particles in an amount of at least 75 wt.-%, based on the total solid weight of the coating composition;
a metallic salt of phosphorous acid; and
a hardener, wherein said epoxy resin includes both liquid type epoxy resin and solid type epoxy resin, and
wherein the amount of said liquid type epoxy resin is 0.5 to 15 wt.-% and the amount of said solid type epoxy resin is 1 to 20 wt.-% based on total weight of the coating composition.