EM-R42 gray bamboo charcoal 1.4D functional fiber, as an innovative environmentally friendly material, is gradually showing its performance and broad application prospects in many fields such as textiles, home furnishings and health protection. This fiber is integrated into the preparation process of 1.4D fine denier fiber, and finally spun into shape to obtain EM-R42 gray bamboo charcoal functional fiber. The addition of bamboo charcoal masterbatch effectively improves the fiber's moisture absorption and perspiration, antibacterial and deodorizing capabilities, while enhancing the fiber's air permeability and temperature regulation functions, bringing users a healthier and more comfortable wearing experience. This fiber not only retains the original moisture absorption and drying, deodorizing and antibacterial, and negative ion penetration characteristics of bamboo charcoal, but also because of its unique 1.4D fine denier design, it gives the fabric a softer and more delicate feel and air permeability. Its cross-section is full of elliptical pores of varying sizes. These pores are like micro-water pumps that can instantly absorb and quickly evaporate a large amount of water, allowing the wearer to enjoy a dry and comfortable experience in any season. The antibacterial performance of EM-R42 gray bamboo charcoal 1.4D functional fiber is particularly outstanding, with an antibacterial rate of up to 94%, effectively inhibiting the growth of bacteria and providing a healthy and safe protective barrier for the wearer. At the same time, the fiber also has anti-ultraviolet ability to protect the skin from ultraviolet damage.