Iron rust conversion agent and preparation method thereof

Abstract

The invention relates to an iron rust conversion agent for removing and preventing rust on the surface of steel. The iron rust conversion agent can be coated on a rusty surface of the steel, the iron rust is conversed into a layer of a protective film, the complicated components of the rust layer are converted into stable products, and the stable products show no rust in the relatively long time in the atmosphere, therefore, the rusty surface of the steel can be directly coated and constructed without removing the rust. A synthetic resin emulsion is used as a main film-forming agent, pyrogallic acid and tannic acid are used as main conversion agents, citric acid is used as an auxiliary conversion agent, and a film-forming auxiliary agent is adopted to realize the curing film-forming at room temperature, thus the compactness and water resistance of the film are improved; and moreover, isopropyl alcohol is used as a solvent and penetrating agent, so as to stabilize the rusty layer. The iron rust conversion agent is sprayed to the rusty surface of the steel, thus a compact and uniform black film is formed on the surface of the steel in short time. In addition, the iron rust conversion agent has advantages of simple preparation process, low cost, stable performance, economy and practicality, safety and environmental friendliness, not containing of toxic and harmful ingredients such as formaldehyde, benzene and nitrite, and no simulation on operating personnel and the like.

Description

technical field [0001] The invention relates to a preparation method of an iron rust conversion agent, which can be applied to the rusted steel surface and can be directly applied without derusting the substrate. The invention belongs to the technical field of steel surface anticorrosion coating. Background technique [0002] Corrosion of steel brings huge losses to the national economy. In order to protect steel components from rust, coating methods are often used. Before using the paint, a thorough derusting treatment must be carried out to remove the rust, scale and other sundries on the steel surface, so that the steel surface is clean and has a certain roughness, so as to ensure a good bonding force between the covering layer and the substrate. Otherwise, the anti-corrosion effect of the paint film will be poor due to the continuous expansion of rust, even if the best anti-corrosion coating is used, it will not be able to play its role. An example has been reported a...

AI Technical Summary

Problems solved by technology

[0004] At present, there are two main types of rust converters, namely, tannic acid type, such as EXITRUST in Australia, and phosphoric acid type, such as KO-99 in the United States. The former can only be used under the condition of a very uniform rust layer, while the latter is prone to rust Whitening, pulverization, etc.

Australia's Krasmer Company has developed a phosphoric acid-type rust conversion agent, which is composed of liquid and solid phases. It is inconvenient to recombine when used, and it contains iron powder, so the cost is relatively high.

Chinese invention patent CN101698938A provides a rust conversion agent, which is prepared from phosphoric acid, tannic acid, ethanol, glycerin, and tap water, which solves the shortcomings of poor rust conversion ability and uneven coating, but has poor water resistance The coating film is prone to whitening when exposed to water, and its stability is poor