Color coated coils are products made by coating organic coatings or plastic films on metal coils as substrates after surface pretreatment. They are widely used in industries such as construction, home appliances, and transportation. However, its quality may be compromised by various factors.
Substrate factors
The quality of the substrate is crucial. If there are untreated oil stains, impurities, oxide scales, etc. on the surface of the substrate, the adhesion of the coating will decrease, causing the coating to easily peel off and bubble. For example, in the production process of cold-rolled substrates, if the rolling oil is not completely removed and the coating is not tightly attached to the substrate after coating, defects may occur in the coating due to prolonged use or exposure to external environmental factors. Moreover, the roughness of the substrate is also important. Improper roughness can result in uneven coating thickness, affecting aesthetics and protective performance.
Coating factors
The quality and performance of the coating itself have a significant impact on the quality of the color coated roll. Improper composition ratios of coatings, such as low resin content and uneven pigment dispersion, can result in reduced flexibility and corrosion resistance of the coating. If there is too much pigment aggregation, the coating surface will appear granular, uneven, and easily worn. In addition, improper selection and use of curing agents in coatings can lead to incomplete curing, insufficient coating hardness, and reduced chemical resistance. When exposed to acidic and alkaline chemicals, the coating is prone to corrosion and discoloration.
Production process factors
There are many coating process steps, and even a slight deviation can affect the quality. Improper selection of coating methods (such as roller coating, spray coating, etc.) during the coating process can result in significant deviation in coating thickness. If the roller pressure is uneven during roller coating, it will cause the coating to have horizontal stripes or uneven thickness. Inaccurate control of curing process parameters (temperature, time, etc.) can affect the curing effect of the coating as mentioned earlier. If the curing temperature is too high and the time is too long, the coating may become brittle; Otherwise, the solidification is incomplete. Moreover, the cleanliness of the production environment also has an impact. If there is a lot of dust and impurities in the air, they will mix into the coating and cause defects.
Storage and transportation factors
Improper storage and transportation conditions during the production of color coated rolls can also damage their quality. If the storage environment is humid, color coated rolls are prone to moisture and rust, especially at the edges. Moisture erosion can cause the coating to bubble and peel off. During transportation, if the coil is subjected to collision or compression, the coating will be scratched or damaged, which will damage the integrity of the coating, reduce its protective and decorative effects, and affect its performance and service life in subsequent use.
Post time: Jan-08-2025