The application of coatings has been very extensive now, that is to say, more and more attention has been paid to coatings. People not only pay attention to the basic performance, characteristics and uses of coatings, but also pay attention to whether the coatings are environmentally friendly, whether they have certificates and so on. So there is paint testing, through testing to determine whether the products they buy are environmentally friendly and whether the quality is up to standard. Usually, many manufacturers also use this to show their superiority. However, many people don't know what items there are in paint testing, and how can we distinguish the quality of paint? The following is a summary of these two issues in Xiaobian.
what are the items for coating testing
1. basic properties: coating thickness, density, viscosity, fineness, moisture content, solid content and acid value
2. physical properties: adhesion, pencil hardness, wear resistance, impact resistance, bending strength, cupping and washing resistance
3. optical properties: color, color difference. Solvent resistance, acid and alkali resistance, oil resistance, detergent resistance and pollution resistance
6. Thermal properties: heat resistance, wet and heat resistance, low temperature resistance, temperature shock resistance, constant temperature and humidity, cold and hot wet cycle
7. Biological properties: anti-mold performance
8. Aging properties: rapid ultraviolet aging, xenon lamp aging, salt spray test, water mist test.
9. Post-aging evaluation: color difference, cracking, foaming, erosion, pulverization and peeling
1. Safety and environmental protection performance: VOC, formaldehyde, benzene, toluene, xylene, free TDI, PAHs? Heavy metal detection EN71-3, ASTM? F963，ROHS? Safety and fire prevention
How to distinguish the quality of paint
1. Leveling: open the can for inspection: open the paint, stir, and observe whether the paint is fine, smooth and free from obvious caking. Pulling out the brush, we can find that the coating can quickly restore its original state, which means that the leveling performance of the product is excellent.
2.? Scrubbing resistance: high-grade paint has excellent scrubbing resistance. If it is simply tested, first, you can write with a watercolor pen on the test paper painted with paint, and then judge whether the paint is harmful to water according to the wiping degree of the handwriting. Scrubbing resistance of colored pens. Then you can try other stains such as crayons and jam. Wait for a few minutes, gently wipe, and the stain will be erased without any damage to the paint film, which shows the excellent scrub resistance of the product.
3.? Covering power: If you encounter some indelible stains, repainting a layer of paint on the original wall is the best solution. Therefore, the covering ability is also an important basis for judging the performance of coatings. We can brush a thin layer of paint on the handwriting on the paint surface for covering, and the test results show that the coverage rate can reach 9%.
4.? Effect of covering cracks: it is also a function that a high-quality coating should have to deal with the problem of wall cracking. When inspecting the product, you can find a cracked wall and then brush it with a layer of paint. When the paint is fully dried, observe whether the paint film has completely covered the cracks. If the cracks completely disappear, it shows that the product has excellent effect of covering the cracks.
5.? Elasticity, flexibility and anti-cracking: for quick detection of products, a layer of paint can be evenly brushed on the surface of inflatable balloons, and the balloons will be deflated slowly after the paint is dried. This process is not small for the elasticity, adhesion and anti-cracking of paint films? Test. During the whole deflation process, the paint film did not appear such as cracking and powder dropping. Even if the balloon is completely deflated, the paint film does not peel off, indicating that its adhesion ability is quite good.
6.? Anti-fouling ability: directly test the anti-fouling ability of the product. You can try to apply daily stains, such as drinks, jam and chocolate, to the paint film. After waiting for a few minutes, try to wipe it directly with a towel or water to see the performance of the product.
what are the items of paint testing, and how can we distinguish the quality of paint? This is roughly the above knowledge. According to the different types of coatings, of course, the focus of coating testing is different, such as interior wall coatings pay more attention to environmental protection, exterior wall coatings pay more attention to sun protection and so on. Many people hesitate to choose paint, fearing that it will not be easy to clean, that there will be scratches after being caught by cats and dogs, and that they will buy fakes. There are too many such worries. I believe reading this article will make you feel more at ease.