Luminous yarn is a new type of functional yarn that can store light energy in fibers as long as it absorbs visible light for 30 minutes. It can continuously emit light for 4-5 hours in the dark and can be reused infinitely. Luminous yarn can emit various colored lights, such as blue light, green light, colorful, long-lasting, high brightness, and is non-toxic and harmless to the human body. It is an environmentally friendly and efficient high-tech product