Enameled wire paint for environmental protection

Winding wire insulation paints are almost all solvent paints in the world. They not only use organic solvents unnecessarily, but also seriously pollute the environment during manufacturing and use, causing damage to living things (humans, animals and plants). Efforts to eliminate this kind of harm have long been committed, especially in recent years, the introduction of ISO14000 will greatly promote this effort. The following is a summary of the experimental research and trial production in this area. As an industrial promotion, it will take some time. It is expected that some varieties may be introduced to the market in the next five to ten years.

(1) No cresol insulating paint

The most common solvent for winding wire insulation paints is cresol. The main component of the mixed solvent is also cresol. Cresol not only poisons the environment, but also has serious corrosive effects on the skin. Solvent systems that currently do not contain cresols are typically based on glycol ethers (such as glycol ethers and diethylene glycol ethers) and their derivatives.

(2) High solid content insulating varnish

At present, the highest solid content of winding wire insulation paint in the world has reached 60-65%. The painting method requires special mold, and the high temperature state of the insulating paint (>65 °C) should be maintained on the equipment.

(3) Extrusion resin

The volatile component of the extruded resin has tended to be zero, and in addition to the special manufacturing techniques, an extremely high precision extruder is required.

(4) UV-curable polymer

Ultraviolet (UV) curable resins do not contain volatile solvents. Currently, acrylic and methacrylic liquid resins have been developed which can be converted into solids under the action of ultraviolet rays. Compared with traditional solvent-based paints, it has a fast reaction time and can form a pinhole-free paint film to overcome the defects caused by solvent evaporation. The disadvantage is that the resin is toxic, high in cost, and poor in thermal performance.

(5) Water-based paint

It is highly desirable to use water as a solvent or medium to make an insulating varnish, since water is non-toxic and tasteless and is a purely natural substance. Waterborne paints include water soluble paints, water emulsion paints and water dispersion paints. The foreign Dr.Beck company pioneered the development, and the domestic Shanghai Cable Research Institute has carried out successful research in the 1970s. In the industrial promotion, measures are still needed.

(6) Powder coating

Powder coatings have been used in a large number of applications in the coatings industry. The electrostatic powder coating on the winding wire has been successfully developed in the manufacture of transformer coils, etc. in cooperation with Westinghouse and 3M after the successful development of ETI (ElectistaticTechuologylnc) in the United States.