As a common industrial and household product, coatings often need to be stored for a period of time after manufacturing before they can be put into use. Coatings can be affected by a variety of factors during storage, such as environmental conditions, packaging quality, and chemical composition, so it is important to check the condition and storage stability of the container when purchasing and using coatings. This article will introduce the inspection methods and standards commonly used in the storage management of coating products.
During the paint sampling process, the condition of the paint in the container needs to be checked in detail to ensure its quality and suitability. The following are common check-ups:
1. Container integrity and logo clarity
Check that the container is intact and free of damage or missing seals.
Confirm that the markings and labels on the container are legible, including information such as product model number, date of manufacture, etc.
2. Inspection items of liquid coatings
Crusting: Whether there is crusting on the surface of the coating, which may affect the performance of the coating.
Delamination: Observe whether there is color or component delamination in the paint, and if so, stir evenly.
Pigment floating or precipitating agglomeration: Check the paint for pigments that are not evenly dispersed, or if they precipitate to form clumps, which may affect the color and uniformity of the paint.
3. The state after stirring
After mixing, the paint should be uniform and consistent, without sedimentation and delamination, and the color should be consistent.
Storage stability refers to whether the coating can maintain its original physical and chemical properties after a certain period of time in the packaging state and under normal storage conditions. Commonly used storage stability testing methods are as follows:
Storage under natural environmental conditions:
Test conditions: Temperature23±2℃, the storage time is 6 to 12 months.
Operation Brief: Divide the paint samples to be tested into a standard gland metal paint tank and store at a defined temperature.
Inspection items: including crusting, corrosion and spoilage odor, particles on the surface of the paint film, glue blocks and brush marks, degree of sedimentation, viscosity changes, etc., and the results are divided into different grades according to the standard.
Artificially Accelerated Conditional Storage:
Test conditions: Temperature 50±2℃, the storage time is 30 days.
Operation Brief: Paint samples are also loaded into standard paint cans and stored in a high-temperature environment for accelerated storage testing.
The results are indicated: Based on the results of the experiments, the stability of the coating under different storage conditions is evaluated, usually in the form of pass or fail.
In addition to visual and manual inspections, the storage stability of coating products can be quantitatively assessed with the help of instruments, such as the application of force Testers:
Measurement of sedimentation velocity
Evaluate the deposition trend of solid particles in the paint by recording the relationship between time and amount of deposition.
Measure the properties of the sediment
A dynamometer probe is used to insert the sediment and the hardness and redispersibility of the sediment are evaluated based on the insertion resistance and depth.
Based on the measurements of the dynamometer, it is possible to further understand the sediment characteristics that may occur during the storage of the coating and help to evaluate its redispersibility after reagitation.
Through the above detailed description of the condition check and storage stability of the container, users and manufacturers can effectively manage the quality and performance of coating products. When purchasing coatings, sufficient testing should be carried out, especially for products that are susceptible to environmental influences such as oxidative drying coatings, and more attention should be paid to the assessment of their storage stability to ensure that the expected coating effect and protection effect can be achieved when used.