Anti-mold agents for adhesives have become a hot topic in recent years, especially since 2006, when developed countries in Europe and America adopted trade protection policies against China, increasingly restricting our exports with environmental thresholds. Although factories have taken various measures to prevent mold, according to incomplete statistics from the customs department, in 2006, the annual export of footwear alone reached 10 billion pairs. At the same time, due to mold spoilage, preliminary statistics from the Ministry of Commerce show that in 2006, 9.8% of China's finished shoes were rejected by foreign customers due to mold, resulting in direct economic losses of US$2.98 billion.
In addition, statistics show that losses from export products have been rapidly growing at a rate of 3.6% in recent years. Entire containers of products being destroyed, rejected, or even claimed for compensation have caused factories great hardship. What exactly happened? Is mold like an invisible, persistent ghost? For this reason, entrusted by the China Industrial Products Anti-bacterial Association, we organized a thirty-person expert group to conduct follow-up investigations on 206 large and medium-sized shoe factories, 83 furniture factories, and 47 handbag factories. We went deep into the factory workshops, from material procurement to cutting, stitching, (shaping) packaging, warehousing, and transportation, and everyone gave an unexpected result: 46.8% of mold growth was caused by adhesive used for lamination, 23.2% by packaging, 13.5% by other reasons, and only 16.5% by the material itself being unclean. This is why mold is becoming more prevalent despite prevention efforts; it turns out that the root cause, adhesives, was not identified.
So why do adhesives become the main culprit for mold? First, general adhesives are composed of polyvinyl alcohol, white latex, sodium stearate, talcum powder, urea, ethylene glycol, sucrose, flavors, water, etc. They have a slightly irritating smell, are volatile, and their volatile gases have a weak tear-inducing effect. To eliminate the irritating smell in adhesives, adhesive manufacturers add a small amount of ammonia water to balance it, achieving a deodorizing effect. However, at the same time, the alkaline environment provides a large amount of breeding nutrients and food for mold, especially the rich sugars and proteins in water-based white latex. Secondly, the Pearl River Delta and Yangtze River Delta regions have a subtropical climate, and maritime transport involves significant temperature and humidity changes, increasing the risk of adhesives getting damp and molding.
The American Society for Testing and Materials (ASTM) points out that to solve the problem of adhesive mildew, American researchers irradiated 10G of adhesive with Pγ rays, then stored it at 30℃ and 80% relative humidity for 360 days, and no mold grew; while un-irradiated adhesive molded after being stored under the same conditions for the same duration. Radiation treatment can achieve sterilization effects, allowing for long-term storage without deterioration. However, the long-term effects of using irradiated adhesive on humans and animals are unknown.
Therefore, for mold prevention in apparel/footwear, Hengyuan's bagged fiber desiccant can be used. Its dehumidifying and anti-mold effects are far superior to silica gel and minerals. Moreover, it is made of all-natural plant fibers, making it environmentally friendly and safe, with no adverse effects on humans or animals, and it is naturally degradable.
