One. Why does anti-corrosion coating take a long time to cure?
1、The amount of curing agent is incorrect.
When purchasing anti-corrosion coatings, it is common to receive a bucket of anti-corrosion coating along with a small bucket of hardener. If the manufacturer's instructions are strictly followed, there should be no issues. However, in actual construction, if a bucket of hardener is used with multiple buckets of anti-corrosion coating to save costs, it can affect the curing time of the coating film.
2、Low ambient temperature
Generally, the application temperature for anti-corrosion coatings should not be lower than 5°C. Otherwise, it will affect the curing time of the coating film. The specific application plan should be determined based on the construction environment and substrate type.
3、Excessive humidity
Some coastal and riverside areas have high humidity, and the moisture in the air adheres to the surface, which can cause anti-corrosion coatings to not solidify or solidify slowly. The construction of anti-corrosion coatings requires the air humidity to be below 85%, and should not be carried out in environments above this level.
4、Excessive coating thickness
Excessive coating thickness is a factor that can affect the curing of anti-corrosion coatings. However, excessive coating thickness typically leads to slower curing, rather than complete failure to cure. When anti-corrosion coatings fail to cure, the root cause should be analyzed and appropriate solutions implemented to prevent recurrence or other common coating defects. Severely defective coatings should be removed and re-applied.
II. How to accelerate the curing time of anti-corrosion coatings
1、Optimize the formulation design of anti-corrosion coatings.
2、Add the appropriate quick-setting thiner.
3. If the ambient temperature is low, take measures to increase it, such as heating the coating environment. For chemically cured coatings, each 10-degree increase in temperature can reduce the curing and drying time by approximately half. However, raising the temperature excessively can negatively affect the coating quality. Typically, the surface temperature of steel should be above 40 degrees to prevent the rapid evaporation of solvents, which can cause bubbles in the coating film.
4. Enhance ventilation to ensure adequate air circulation on the coating surface, and promptly remove solvent vapors. Increasing air circulation can reduce curing time, improve curing efficiency, and ensure high-quality curing.
5. Control humidity, as humidity affects the evaporation of solvents.