Weldable coating compositions
First Claim
1. In a weldable coating composition for metallic substrates which comprises in admixture a high molecular weight epoxy or phenoxy resin, an electroconductive pigment and an diluent;
- the improvement which comprises replacing at least about epoxy or phenoxy resin with a composition consisting essentially of;
(A) a low molecular weight epoxy resin or mixture of epoxy resins having an average of more than one vicinal epoxy group per molecule;
(B) a hydroxyl-containing or thiol-containing material or mixture of such materials which is (1) a polyhydric phenolic or thiophenolic compound or (2) the product of reacting (a) a low molecular weight epoxy resin having an average of more than one vicinal epoxy group per molecule with (b) a polyhydric phenolic or thiophenolic compound wherein the phenolic hydroxyl or thiol to epoxy equivalent ratio is from about 2;
1 to about 12;
1;
(C) a catalytic quantity of a catalyst for effecting the reaction between (A) and (B);
wherein (A) and (B) are present in quantities such that the hydroxyl or thiol to epoxy equivalent ratio is from about 0.5;
1 to about 1.1;
1.
1 Assignment
0 Petitions
Accused Products
Abstract
An improvement in a weldable coating for metallic substrates containing a high molecular weight epoxy or phenoxy resin, an electroconductive pigment such as zinc and a diluent such as a glycol ether wherein the improvement resides in replacing at least about 70 weight percent of said resin with a composition containing a low molecular weight epoxy resin such as the diglycidyl ether of bisphenol A, a phenolic hydroxyl-containing compound such as a phenolic hydroxyl terminated adduct of a diglycidyl ether of a diphenolic compound such as bisphenol A and a catalyst for effecting the reaction between the epoxy resin and the adduct.
66 Citations
27 Claims
-
1. In a weldable coating composition for metallic substrates which comprises in admixture a high molecular weight epoxy or phenoxy resin, an electroconductive pigment and an diluent;
- the improvement which comprises replacing at least about epoxy or phenoxy resin with a composition consisting essentially of;
(A) a low molecular weight epoxy resin or mixture of epoxy resins having an average of more than one vicinal epoxy group per molecule; (B) a hydroxyl-containing or thiol-containing material or mixture of such materials which is (1) a polyhydric phenolic or thiophenolic compound or (2) the product of reacting (a) a low molecular weight epoxy resin having an average of more than one vicinal epoxy group per molecule with (b) a polyhydric phenolic or thiophenolic compound wherein the phenolic hydroxyl or thiol to epoxy equivalent ratio is from about 2;
1 to about 12;
1;(C) a catalytic quantity of a catalyst for effecting the reaction between (A) and (B); wherein (A) and (B) are present in quantities such that the hydroxyl or thiol to epoxy equivalent ratio is from about 0.5;
1 to about 1.1;
1. - View Dependent Claims (2, 3, 4, 5, 6)
- the improvement which comprises replacing at least about epoxy or phenoxy resin with a composition consisting essentially of;
-
7. A weldable coating composition comprising:
-
(A) a low molecular weight epoxy resin or mixtures of thereof having an average of more than one vicinal epoxy group per molecule; (B) a hydroxyl-containing or thiol-containing material or mixture of such materials which is (1) a polyhydric phenolic or thiophenolic compound or (2) the product of reacting (a) a low molecular weight epoxy resin having an average of more than one vicinal epoxy group per molecule with (b) a polyhydric phenolic or thiophenolic compound wherein the phenolic hydroxyl or thiol to epoxy equivalent ratio is from about 2;
1 to about 12;
1;(C) a catalytic quantity of a catalyst for effecting the reaction between (A) and (B); (D) an electroconductive pigment and; wherein the equivalent ratio of phenolic hydroxyl or thiol groups in (B) to epoxy groups in (A) is from about 0.5;
1 to about 1.1;
1; and(E) a diluent or solvent in an amount of from about 2% to about 40% by weight of the total composition. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
Specification