Waterborne alkyd resin coatings are widely used for general protection of metal, wood and other surfaces. Today we will introduce the regulations of HG/T 4847-2015 on waterborne alkyd resin coatings .
Item detection
1. State in the container: First, we open the container, stir with a spatula or stir bar, and allow precipitation at the bottom of the container. If the primer sample and topcoat sample are easy to mix evenly after stirring, it is rated as "homogeneous and no hard lumps after stirring".
2. Viscosity: Use Tu-4 cup for testing, and the testing standard is determined by both parties according to actual requirements.
3. Fineness: If the primer sample is ≤60μm and the topcoat sample is ≤30μm, it is regarded as up to standard.
4. Skinning property: Put the primer sample and topcoat sample in the sample for 48 hours, take it out after the end to test the fluidity of the surface layer, if the surface layer is kept in a liquid state, it can be rated as "no skinning".
5. Freeze-thaw stability: The sample is subjected to three cycle tests, and the observation result is that it does not deteriorate, and it is considered to be up to standard.
6. Thermal storage stability: Put the sample in a constant temperature Drying Oven at 50°C±2°C, take it out after 7 days, and observe it after placing it at 23°C±2°C for 3 hours. If it is evenly stirred without hard lumps, it will be rated as "passed" ".
7. Hiding power: The covering power of white topcoat is ≤200g/m², black ≤45g/m², and other colors are determined by the testing parties according to the actual situation.
8. Non-volatile matter content: the primer sample and the top paint sample ≥ 40%, which is considered to be up to the standard.
9. The content of volatile organic compounds: the primer sample and the top paint sample are ≤300g/L, so as to meet the standard.
10. Workability: Choose the coating method to paint the test panel. If there is no obvious resistance during the coating process, no obvious drawing, bubbles, sags, etc., it can be rated as "construction barrier-free".
11. Appearance of the paint film: If the sample has no wrinkles, stains, particles, shrinkage cavities and uneven gloss, it can be rated as "normal".
12. Inhibition of flash rust: If there is no rust on the surface of the paint film and no rust spots on the substrate by visual observation, it is rated as "normal".
13. Drying time: the surface dryness of the primer sample and the topcoat sample is ≤8h, and the solid dryness is ≤24h.
14. Bending test: If the bending parameters of the primer sample and the top paint sample are ≤3mm, it is regarded as up to standard.
15. Impact resistance: If the bending parameters of the primer sample and the topcoat sample are ≥3cm, it is considered to be up to the standard.
16. Cross-cut test: test with a cross-cut interval of 1 mm, and the primer sample and topcoat sample are ≤ grade 1, which is considered to be up to standard.
17. Gloss: 60° is used, and the parameters are determined by the two sides of the test according to the actual situation.
18. Hardness: If the topcoat sample ≥ 0.2, it is considered up to standard.
19. Water resistance: If the topcoat sample is immersed in water for 24 hours, and then visually observed under scattered light after the end, if there is no abnormality of the coating film, it can be rated as "no change".
20. Salt water resistance: If the topcoat sample is immersed in 3% NaCl for 24 hours, rinse it with running tap water after the end, and visually observe it under scattered light. If there is no coating film sickness, etc., it can be rated as "no change" .
21. Resistance to artificial weathering: If the topcoat sample has no peeling, blistering, cracking, and pulverization, and the white, black, and discoloration are ≤2 grades, and the color loss is ≤3 grades, it is considered to be up to the standard.
