Shanghai wax powder manufacturers take you to understand the application characteristics of rapid curing polyester in powder coatings

Shanghai wax powder manufacturers take you to understand the application characteristics of rapid curing polyester in powder coating:

For the fast curing powder coating, the traditional concept is that the purpose of fast curing can be easily achieved by adding curing accelerator in the formula design of powder coating. However, excessive reliance on additives often brings other adverse complaints, such as: poor leveling, baking yellow fading, powder heat storage performance is poor. In this paper, based on the actual construction conditions of low temperature curing texture and flat flour, conventional sand wrinkle powder, heat transfer powder, etc., the apparent properties of coating film, mechanical properties and the requirements of thermal storage stability of powder are discussed to demonstrate the influence of the selection of different reactive polyester on various performance indexes, and finally put forward the overall solution.

Fast curing polyester in the use of powder coatings often has the following help in the following aspects. For example: (1) improve the crosslinking density, thereby improving the film hardness, grid adhesion, impact resistance and other mechanical properties; (2) Reduce the curing temperature or shorten the curing time to achieve low temperature curing or rapid curing; (3) Hinder the melting and leveling of the powder, and achieve apparent control of the size and three-dimensional sense of the texture; (4) Interspersed with the slow or medium speed curing system to interfere with each other, and reduce the apparent luster while leveling. However, fast curing polyester in the above advantages at the same time, other disadvantages are slowly revealed. For example: (1) the heat storage stability is not good, and the powder coating made is easy to cluster; (2) The film leveling performance is poor, and it is easy to appear orange peel. For this reason, a successful fast curing polyester product must balance the two contradictory indicators of mechanical properties and leveling properties, thermal storage stability and curing conditions. In order to adapt to the use of different types of powder coatings, rapid curing polyester has different emphasis on the above indicators in research and development and production engineering; Therefore, the classification is different, and the use characteristics are also different. The following will specifically introduce several types of fast curing polyester and their corresponding use characteristics.

2. The application of fast curing polyester in thermal transfer powder coating

The difficulty of thermal transfer powder coating has always been the problem of tearing paper. Tear paper effect is good, there is no imprint or less imprint, transfer production efficiency is high; It is not good to tear paper or stick paper, then the impression is obvious, and the production efficiency is low. After many experiments, the results show that the main factors affecting the film transfer paper tearing are: (1) the hardness of the film, the higher the hardness, the better the paper tearing; (2) the complete degree of polyester curing, the faster the curing speed, the more complete, the better to tear the paper; (3) The distribution of polyester molecular weight, the larger the molecular weight, and the narrower the distribution, the better the tear paper.