Selection of fungicides that meet the requirements of green water-based building coatings (3)

3.2 Dry film anti-mold agent
wall painted water-based architectural coating, due to the substrate or film surface is contaminated, the environment is humid, not enough light and other reasons, but also vulnerable to microorganism infestation, long mold, color change, shedding phenomenon, seriously affecting the appearance, but also lost protection function. Especially for toilets, basements, garages and other dark and humid conditions of the interior wall paint, paint film mold phenomenon is particularly serious, must be added to the product dry film mold inhibitor to prevent.
Commonly used dry-film anti-mold agents are benzodiaminolamide (i.e., polybacterial, referred to as BCM), hinge isoprene (OIT), diclosin isosterone (DCOIT), zinc pyrithione (ZPT), iodine-based acetaminophen (IPBC) and so on, its main performance pairs such as Table 7.of the products listed in Table 7, BCM is widely used because of its moderate price and superior overall performance, but it is prohibited in the new green label because it is harmful to the ecological environment. ZPT and IPBC use in addition to the limit requirements, the focus should be on the adaptability of the formula, that is, whether the tendency to change color is within acceptable range. In addition to the formulation adaptability, OIT and DCOIT also consider that the total IT content should be controlled to 750 mg/kg.
2 shows the MIC (minimum anti-bacterial concentration) of commonly used anti-mold agents, from which we can see the inhibitory effect of each anti-mold agent active agent on different molds. Given that individual mold inhibitor actives are very high for individual mold MIC, the market also tends to match two or more active substances to achieve synergies.
addition, considering the use of internal and external wall coatings different places, the product's anti-mold performance requirements are also different, such as external wall coatings need to take into account the water solubility of anti-mold agent, DCOIT is not very suitable. Therefore, while meeting the green coating, it is also necessary to take into account the other properties of the coating.3.3 Dry film anti-algae agent
external wall coating surface under high humidity exposure to sunlight will have algae growth, the same will affect the appearance of the paint film, or even cause paint film damage, so the need to add dry film anti-algae agent.
The most commonly used dry film anti-algae agent is the enemy grass rumbling, this GB/T35602-2017 requirements must not add enemy grass rumble, the author and industry experts fully exchange, learn from the relevant experience of Europe and the United States, recommended the use of Tedin net. The performance comparison between Tedin Net and Enemy GrassLong is shown in Table 8.3.4 Comprehensive consideration of fungicides in formulations
When selecting fungicides in water-based building coatings, consider also the variety and quantity of fungicides added to other components of the formula, such as emulsions, color pastes, dispersants, desiccants, thickeners and other sterilizers that may be brought in, if these raw materials have banned products, suppliers should be required to replace;
in accordance with 3.1 to 3.3 selected in line with the green water-based building coating standards of the fungicide, but also according to the actual use of paint products for storage and challenge experiments, and batch trial, to ensure that the final performance of the product is met.4 Conclusion
In summary, water-based building coatings to meet GB/T 35602-2017 "Green Product Evaluation Coatings" standard requirements, dbNPA can be used as a quick-killing preservative, MIT/BIT compound as a long-acting preservative, OIT compound ZnP or IPBC as anti-mold agent, special butine as anti-algae, testing and batch testing, to achieve comprehensive performance requirements..