This will happen if the main agent and curing agent are mixed and stirred unevenly. Hailian Daye suggested that the edge scraping and bottom cleaning should be paid attention to during the mixing process to ensure the uniformity of mixing. If possible, after mixing the main agent and curing agent evenly, pour it into another cup and stir for a while before injecting the product. Take-up container and stirring rod (including cups, etc.). ) Containers with smooth surfaces, such as metal, plastic and glass, must be used, and paper and wood containers are not allowed, because the surface of the latter material has micropores, which can easily bring air and moisture into the resin system, thus affecting the curing quality. Make sure that the container and stirring rod are dry before taking the materials. If conditions permit, the container and the stirring rod can be heated (80℃) for about 30 minutes. If the conditions are not met, at least wipe them with a dry rag. In order to ensure uniform mixing, when stirring by hand, it is suggested that the stirring time is 10- 15 minutes. At the same time, we should pay attention to the stirring intensity and try not to bring air into the resin.