The leather used contains a nutrient source for mold growth. Leather is the product of natural polymer compounds, and its main components are collagen and fat. In the processing technology of leather, a lot of animal and vegetable oils, inorganic salts and minerals are often added. These are the nutrient sources needed for mold growth, plus the ubiquitous mold spores in the air. Generally, the storage environment will be relatively stable, and if the air is humid, mold will easily breed. According to the research and analysis of the research department () of anti-mildew and anti-bacterial technology for hobby children, the main reasons leading to moldy footwear products are: 1. The application of new materials, such as high-quality heavy materials or water-based finishing agents, are all fungi. The breeding of mold provides a hotbed. 2. EU strictly restricts the use of heavy metal chemical additives such as pesticides and preservatives, so that a large number of bacteria and molds produced in leather products can survive. 3. The temperature and humidity during storage or shipping are too high, resulting in "container rain", which increases the risk of products being damp and moldy. Yes