Successful production of electrostatic powder coating

For the first time, scientists of the Institute of Chemistry (Vietnam Institute of Science and Technology) have researched, manufactured and successfully applied the technology of producing electrostatic powder paint. This success has opened the direction of producing electrostatic powder coatings to meet domestic demand, limit imports and protect the environment.

Production of electrostatic powder paints at the Institute of Chemistry. (Photo: Nhandan) To serve the process of socio-economic development, especially the construction industry, civil . to protect and decorate, each year Vietnam consumes a large amount of paint. . The main and largest paints used are mainly liquid paints.

About 10 years ago, countries around the world have gradually replaced the paint solution with powder paint. This conversion step is not only economically significant but also plays an important role in protecting the water environment because in liquid paint, the amount of solvent accounts for about 40-50% will escape to the air, causing environmental pollution. school In Vietnam in the past few years, the demand for powder coating has also increased dramatically in the automobile and motorbike manufacturing industries to paint machine parts, in civil and industrial construction structures. . However, the amount of powder coating in the country cannot be produced but must be imported. Vietnam paint market has gradually appeared many types of powder paint brands: Dupont, ICI, Jotun . to serve domestic consumption demand.

Facing the challenges and demands of powder coating, the success in researching the technology of producing electrostatic powder coatings (unidirectional electric fields with voltage from 40-120KV) independent of foreign countries has opened up the possibility of application. Producing Vietnamese brand electrostatic powder paint.

On the basis of Epoxy DER662, DER663, DER672 and phenolic curing agents DEH80, DEH84, DEH90 with catalyst 2 methyl imidazol, domestic scientists have built and fully mastered the technological process of powder coating production. electrostatic; At the same time, the standards and methods for assessing the quality of electrostatic powder coatings such as the amount of pigment and powder, the amount of pile and shaking, the flow of powder, the ratio, dispersion, and properties are determined. Mechanical properties of paint film.

During the study, the scientists also selected the type of TiO ₂ base additive system and use modified CaCO ₃ powder with locally produced paraffin suitable for the production of powder coating to reduce production costs. .

According to Assoc. Prof. Dr. Do Truong Thien - Chairman of the research project, in the technology of producing electrostatic powder paint, the most important factor determining the quality of paint is the technology of mixing in the state of flowing and superfine grinding. . Electrostatic paint must be mixed on the screw mixing device with the most appropriate temperature from 95 - 105 ⁰ C and crushed according to the principle of hammering the rotational speed of the rotor more than 7,000 rpm with the grinding chamber temperature not exceeding 50 ⁰ C.

Not only is it technologically successful, Vietnam has been able to manufacture its own equipment to produce electrostatic powder paint, including: dry mixing equipment with capacity of 40 kg / batch, screw mixing with capacity of 1.75 KW with 10 - 15 kg / h capacity, electrostatic spray equipment 60 - 120KV, electrostatic spraying chamber with recovery principle of cyclone and bag of drying chamber with highest temperature of 250 ⁰ C.

On the basis of mastering the technology, the research team produced more than 3,000 kg of powder paint in black, white and red colors to paint more than 10,000m2 of products which are details of petrol pump casing, steel frame structure of the factory. Thai Binh plating, motorbike details, electric cooker cover, gas stove frame .; at the same time providing test products for the Union of Science and Technology for New Materials and Equipment Manufacturing, Nam Thang Electrostatic Coating and Technology Co., Ltd, the number of electrostatic painting enterprises under the Development Consultancy Company. Construction for civil works.

According to experts, although this is the first product that has been successfully researched and produced in Vietnam, it can guarantee nearly equal quality and cheaper price than static powder coating products. Imported electricity is available in Vietnam market .

Electrostatic powder coating products are not officially available in the market but the applicability is very large. Dr. Thien said, a factory producing electrostatic powder paint with a capacity of 1,000 tons / year has been studied and developed. However, in order to serve the domestic market needs, it is necessary to continue through the pilot production project to continue improving the technology.