Hygroscopic powder paint itself (moisture) directly affects the power self resistance Yong dielectric constant. If severe moisture will agglomerate powder.This is not for electrostatic coating. The general moisture, in addition to its effects on live performance, will also reduce the flow of powder and film, the filmis not smooth and even difficult to the workpiece on adsorption and film will produce bubbles and pinhole.
Moisture absorbing and do not pay attention to save storage caused by powder coating, and spraying of compressed air purification degree. Because of easy to produce condensation water in the compressed air in the air purification system,there must be a filtering moisture absorption device, which is reduced to the minimum degree of moisture in the air to the powder supply device.
In addition, powder spraying field relative humidity of the air is to be attached.Data report, relative humidity 30% change, changes of resistivity is equivalent to the powder of two orders of magnitude (omitted). Specialty Carbon Black
the stability of powder coatings
The stability of powder coatings are powder during storage or whether the occurrence of powder agglomeration in use, flow characteristics of variation,charged effect is poor, the film orange peel was weakened, gloss, pinhole bubble generation etc..
In the production of powder coatings, attention must be paid to its storagestability, only with a certain stability of powder coating, can let the users. Abroad,often adding some additives in powder coatings, powder coatings to enhance the stability, so this kind of powder coatings in general in the damp or high temperature 70-75. also won't produce agglomerate.
The stability of Powder Coatings powder coating is used at a certain temperature, the flow changes to determine treatment after a certain period of time. Because of the stability of Powder Coatings powder coating in the storageconditions and the molecular cross-linking degree of crosslinking reactionoccurred; powder more intense, the molecular weight of powder, as reflected in the powder in the curing temperature viscosity, and flow characteristics of variation.