Observe if the color coated steel sheet paints have crust, gel, delamination, precipitation, fineness and other conditions, it’s preferably measure the storage stability of the color coated steel sheet paints in accordance with the national standard GB 6753.3-86.
After the paint is opened, it is often found that there is a layer of crust on the uppermost layer, which is formed by the oxidation and solidification of the alkyd paint. To observe the extent of crusts, if there has crust, then remove along the inner wall of the container. Crust has been unable to use, but the underlying paint can continue to use. However, CAMELSTEEL recommend that it’s better to stir them evenly before use.
When the paint appears gel phenomenon, staff can stir or add the solvent and then stir. When filter during use, if it can not disperse into a normal state, then the paint will scrap.
After the paint storing for a period of time, the paint may appears stratification. Paint particles sink, forming a layer of water solution above the upper quarter, that indicate the quality of the paint is very good. If the water solution was turbid, showing the paint colors or a large number of internal floating objects, or even covered with the solution surface, that indicate the poor quality of paint or shelf life is expired. It is not suitable to use.
4. Particles fineness of the paint
It can be checked by a cup of water. Take a small amount of paint into the water, if the cup of water is still crystal clear after gently stirring, the coating particles in water is relatively independent, there is no adhesion, and the particle size is more uniform. That indicate the paint quality is very good. If once agitated, the water in the cup immediately becomes cloudy, and the particle size becomes differentiation. That indicate the paint quality don’t reach a standard. It is not suitable to use.
5. Appearance and colour
The paint used in paint production line is the colloidal particle body with color. The normal appearance requirements are same color, and does not produce floating color. It also does not allow there’s dark or shallow color.