Anti-corrosion coating refers to a type of liquid that can form a thin film on the surface of an object to perform protection, decoration or other special functions (insulation, rust prevention, mildew prevention, heat resistance, etc.) under certain conditions. or solid material. Because most of the early coatings used vegetable oil as the main raw material, they were also called paints. Now synthetic resins have mostly or completely replaced vegetable oils, so they are called coatings.
It has three main functions: protection, decoration, and concealment of product defects to enhance the value of the product.
Main types:
Epoxy anti-corrosion coating.
Epoxy anti-corrosion coatings usually consist of two components: epoxy resin and curing agent. The nature of the curing agent also affects the performance of the paint film. Commonly used curing agents are: aliphatic amines and their modifications, which are characterized by being curable at room temperature. Unmodified aliphatic amines are more toxic.
Aromatic amines and their modifications are characterized by slow reaction. Often required to be heated and cured, with weak toxicity, perchlorethylene paint, polyamide resin, characterized by good weather resistance, low toxicity, good elasticity, slightly poor corrosion resistance, phenolic resin, urea-formaldehyde resin and other synthetic resins.
Grease paint.
Grease paint is a type of paint that uses dry oil as the main film-forming substance. It is characterized by easy production, good brushability, good wettability to the surface, low price, and flexible paint film, but the paint film dries slowly, is soft, has poor mechanical properties, and is resistant to acid and alkali, water and water. Poor organic solvent resistance. Dry oil is often combined with anti-rust pigments to form anti-rust paint, which is used in atmospheric environments with low corrosion resistance requirements. Raw paint, also known as national paint and lacquer, is one of my country's specialties.
Raw lacquer.
Raw lacquer is a milky white viscous liquid that flows out from the bark of the growing lacquer tree. It is filtered through fine cloth to remove impurities. After it is painted on the surface of an object, its color quickly changes from white to red, and from red to purple. After a long time, it can turn into a hard and shiny black paint film. Urushiol is the main component of raw lacquer, with a content of 30 to 70%. Generally speaking, the higher the urushiol content, the better the quality of the raw paint. Raw paint has strong adhesion, tough paint film and good gloss. It is resistant to soil corrosion, water and oil. The disadvantage is that it is toxic and can easily cause skin allergies. In addition, it is not resistant to strong oxidants and has poor alkali resistance.
Modified raw lacquer latex paint.
There are now many modified raw lacquer latex paints, which have overcome the above shortcomings to varying degrees. Resin coatings: phenolic resin coatings: mainly include alcohol-soluble phenolic resin, modified phenolic resin, pure phenolic resin, etc. Alcohol-soluble phenolic resin coatings have good corrosion resistance, but they are inconvenient to construct, have poor flexibility and adhesion, and their applications are subject to certain limitations. Therefore, it is often necessary to modify phenolic resins. For example, by refining rosin-modified phenolic resin with tung oil, adding various pigments, and grinding, various enamels can be produced. The paint film is tough and cheap, and is widely used in the coating of furniture, doors and windows. Pure phenolic resin coating has strong adhesion, water resistance, humidity and heat resistance, corrosion resistance and good weather resistance. Epoxy resin coating: Epoxy coating has good adhesion, excellent adhesion to metal, concrete, wood, glass, etc., is resistant to alkali, oil and water, and has excellent electrical insulation properties. But its anti-aging properties are poor. ?