Among the various paints used in aluminum plates, fluorocarbon resin has particularly superior characteristics: weather resistance, heat resistance, low temperature resistance, chemical resistance, and unique non-stickiness and low friction. These excellent characteristics make fluorocarbon resin widely used in various fields such as construction, chemical industry, electrical and electronic industry, machinery industry, aerospace industry, household goods and so on.
1. Types of fluorocarbon resin
The most common ones in the fluorocarbon resin family are PVDF and FEVE.
PVDF is polyvinylidene fluoride resin, which appeared in the 1960s and is mainly used as a building coating for metal decorative plate protective coatings. After thirty years of real tests, the original appearance is basically maintained. The fluorocarbon-coated metal baking paint type must pass through high temperature to form a film, and cannot be applied at normal temperature.
FEVE, which is polychlorotrifluoroethylene / vinyl ether resin, was successfully developed by Japanese scientists in 1982 using molecular chain design technology and membrane technology.
It is a fluorocarbon coating that can be cured at room temperature. At normal temperature, the fluorocarbon coating is applied to the surface of various substrates by brushing, roller coating, spraying and other common coating methods to form a fluorocarbon protective coating, which greatly expands the scope of application of fluorocarbon coatings. Fluorocarbon coatings in daily life.
2. Characteristics of fluorocarbon resin
The fluorocarbon coating for curtain wall material coating is a kind of organic coating based on fluorocarbon resin, with metal particles or mica crystal as toner, and its PVDF (polyvinylidene fluoride) content is 70% (resin Mass ratio) above. The chemical structure of the fluorocarbon base material is bonded by a fluorine / carbon chemical bond, which is considered to be the most stable and strongest bond so far. Under normal circumstances, it has the following excellent performance:
Weather resistance—It has the ability to resist bad weather and ultraviolet rays, so it can maintain color and gloss for a long time;
Corrosion resistance—It is resistant to acid and liquid alkali and is not affected by air pollution and acid rain. The permeability of oxygen, moisture and corrosive particles is low, and it can withstand the harsh environment for a long time without corrosion.
Mechanical properties—Excellent impact resistance, wear resistance and excellent paint film flexibility.
In the coating named KYNAR500®, the required weight ratio of KYNAR500® resin is ≥70%. The reason is that when the resin content is 70%, the performance of PVDF, especially the weather resistance and durability, can meet the higher requirements, and when it is greater than 70%, its performance impact is not large, basically 70% In the same performance state, and the primer content is 30% and 70% PVDF match, the best performance KYNAR500®resin content is less than 70%, the name of KYNAR500® coating is not allowed.
3. Coating method of fluorocarbon resin paint
There are many coating methods for fluorocarbon resin coating, which can be roller coating, spray coating or electrostatic powder coating. Different coating methods require different production equipment and substrate treatment requirements, and the resulting coating thickness and coating effect are also different.
