Solventless epoxy-based coating composition, method of applying and article coated therewith

Claim 1

A coating composition having a viscosity less than about 1000 cps. which is substantially free of volatile solvent consisting essentially of: (a) an epoxy fraction consisting of polyphenol epoxy resins and mixtures thereof; and, (b) a curing fraction consisting essentially of: (1) about 20-80 wt.-% based on the total coating composition of a non-volatile, aromatic extender selected from the group consisting of coal tar, distillates of coke and petroleum with boiling points above about 200° C., and mixtures thereof; (2) an amine curing agent having a molecular weight of about 200-600 selected from the group consisting of: (i) cycloaliphatic diamines having a single amine group directly attached to a single ring structure and the other amine group directly attached to a carbon atom in an aliphatic chain or to a second ring structure; (ii) polyamines having polyaliphatic oxide back-bones; and, (iii) mixtures thereof; and, (3) a curing accelerator selected from the group consisting of tertiary amines.

Claim 13

A method of coating the surfaces of solid articles with a protective coating which comprises the steps of: (a) preparing an epoxy fraction consisting essentially of polyphenol epoxy resins; (b) preparing a curing fraction consisting essentially of an amine curing agent and from about 20-80 wt.-% based on the total coating composition of a non-volatile, aromatic extender wherein said amine curing agent has a molecular weight of about 200-600 and is selected from the group consisting of: (i) cycloaliphatic diamines having a single amine group directly attached to a single ring structure and the other amine group directly attached to a carbon atom in an aliphatic chain or to a second ring structure; (ii) polyamines having polyaliphatic oxide back-bones; and, (iii) mixtures thereof; and said aromatic extender is selected from the group consisting of coal tar, distillates of coke and petroleum with boiling points above about 200° C. and mixtures thereof; (c) aging said curing fraction for about twenty-four hours or longer; (d) combining the epoxy fraction and the curing fraction in the absence of volatile solvent to obtain a composition having a viscosity less than about 1000 cps; and, (e) applying the resulting composition to the surfaces of the articles to be covered.

Claim 14

A method of coating the surfaces of solid articles with a protective coating which comprises the steps of: (a) preparing an epoxy fraction consisting essentially of polyphenol epoxy resins; (b) preparing a curing fraction consisting essentially of an amine curing agent and from about 20-80 wt.-% based on the total coating composition of a non-volatile, aromatic extender wherein said amine curing agent has a molecular weight of about 200-600 and is selected from the group consisting of: (i) cycloaliphatic diamines having a single amine group directly attached to a single ring structure and the other amine group directly attached to a carbon atom in an aliphatic chain or to a second ring structure; (ii) polyamines having polyaliphatic oxide back-bones; and, (iii) mixtures thereof; and said aromatic extender is selected from the group consisting of coal tar, distillates of coke and petroleum with boiling points above about 200° C. and mixtures thereof; (c) aging said curing fraction for about twenty-four hours or longer; (d) combining the epoxy fraction and the curing fraction in the absence of volatile solvent to obtain a composition having a viscosity less than about 1000 cps; and, (e) applying the resulting composition to the surfaces of the articles to be covered.