Under normal conditions, the lifespan of photochromic fluorescent anti-counterfeiting ink under sunlight is 30 days. With the development of printing and new material technologies, the indoor lifespan of photochromic fluorescent anti-counterfeiting ink has been greatly improved, and even can be used indefinitely. The main function of photochromic fluorescent anti-counterfeiting ink is to exhibit bright and vibrant colors in printed materials. The advantages of fluorescent ink during printing include thin ink layer, precise background, fast drying, etc., which should be determined based on the characteristics and printing method of the printed material.

In the anti-counterfeiting printing of invoices, fluorescent ink is usually used, but the process requirements are relatively high, requiring advanced technology and rich experience. When printing the supervision seal with fluorescent ink on watermark anti-counterfeiting paper, there are usually quality problems such as paper fuzzing and shedding, dirty and pasted layout, especially in cold winter when the temperature is low. In addition, there are serious and prominent problems of ink viscosity and strong adhesive film. Later, through the exploration and technological innovation of printing enterprises, the addition of No. 6 ink thinner in fluorescent ink has solved these problems very well, and the overall production efficiency has also been improved.