Two-component coating composition and coating method thereof

Abstract

A two-component coating composition comprises a first component and a second component. The first component comprises: 50-75% by weight of a film-forming substance comprising an alkyd resin; 20-35% by weight of a diluent comprising unmodified cashew nut shell powder; 5-20% by weight of a pigment; and 0.5-8% by weight of a coating additive. The second component comprises: a curing accelerator, the active ingredient of which comprises at least one aliphatic or alicyclic polyisocyanate compound. The weight ratio of the total weight of the alkyd resin, the diluent, the pigment, and the coating additive to the weight of the curing accelerator is 100:1 to 3:1.

Claims

1. A two-component coating composition comprising a first component and a second component, the first component comprising: 50-75% by weight of a film-forming substance comprising an alkyd resin; 20-35% by weight of a diluent comprising unmodified cashew nut shell extract; 5-20% by weight of a pigment; and 0.5-8% by weight of a coating additive; the second component comprising: a curing accelerator, the active ingredient of which comprises at least one aliphatic or alicyclic polyisocyanate compound, wherein the total weight ratio of the alkyd resin, the diluent, the pigment, and the coating additive to the weight ratio of the curing accelerator is 100:1 to 3:1, wherein the polyisocyanate compound reacts with the hydroxyl groups in the unmodified cashew nut shell extract to form a cross-linked structure, thereby enabling film formation at room temperature even when a high proportion of unmodified cashew nut shell extract replaces the organic solvent.

2. The two-component coating composition as claimed in claim 1, wherein the film-forming substance further comprises a petroleum resin.

3. The two-component coating composition as claimed in claim 1, wherein the diluent further comprises an organic solvent, wherein the organic solvent in the diluent comprises at most 90% by weight.

4. The two-component coating composition as claimed in claim 1, wherein the pigment is selected from organic pigments, inorganic pigments, and combinations thereof.

5. The two-component coating composition as claimed in claim 1, wherein the coating additive is selected from dispersants, leveling agents, defoamers, anti-skinning agents, metal desiccants, and combinations thereof.

6. The two-component coating composition as claimed in claim 1, wherein the polyisocyanate compound is hexamethylene diisocyanate or an oligomer thereof.

7. The two-component coating composition as claimed in claim 6, wherein the hexamethylene diisocyanate oligomer is a hexamethylene diisocyanate trimer or a biuret-type hexamethylene diisocyanate.

8. A method for applying a surface coating, comprising: a preparation step, mixing a first component comprising 50-75% by weight of a film-forming substance, 20-35% by weight of a diluent, 5-20% by weight of a pigment, 0.5-8% by weight of a coating additive, and a second component comprising a curing accelerator to obtain a two-component coating composition; a coating step, coating the two-component coating composition onto a substrate surface; and a curing step, allowing the coating to stand at room temperature to form a surface coating, wherein in the preparation step, the film-forming substance comprises an alkyd resin, the diluent comprises unmodified cashew nut shell powder, the curing accelerator comprises at least a polyisocyanate compound, the weight ratio of the total weight of the alkyd resin, the diluent, the pigment, and the coating additive to the weight of the curing accelerator is 100:1 to 3:1, and the polyisocyanate compound reacts with the hydroxyl groups in the unmodified cashew nut shell powder to form a cross-linked structure.

9. The coating method as claimed in claim 8, wherein in the preparation step, the film-forming substance further comprises a petroleum resin.

10. The coating method as claimed in claim 8, wherein in the preparation step, the diluent further comprises an organic solvent, wherein the organic solvent in the diluent comprises at most 90% by weight.

11. The coating method as claimed in claim 8, wherein in the preparation step, the pigment is selected from organic pigments, inorganic pigments, and combinations thereof.

12. The coating method as claimed in claim 8, wherein in the preparation step, the coating additive is selected from dispersants, leveling agents, defoamers, anti-skinning agents, metal desiccants, and combinations thereof.

13. The coating method as claimed in claim 8, wherein in the preparation step, the polyisocyanate compound is hexamethylene diisocyanate or an oligomer thereof.

14. The coating method as claimed in claim 13, wherein in the preparation step, the hexamethylene diisocyanate oligomer is a hexamethylene diisocyanate trimer or a biuret-type hexamethylene diisocyanate.