It is easy to be confused with background advertisements and the like. The yellow color is better, and it also enriches the colors of the field and makes the picture more beautiful. This is theory. In fact, the yellow ball will age slightly faster, but this speed is very small. This is because the wavelength of yellow light will cause the object itself to age faster - this is the reason why yellow areas on a piece of cloth will rot more easily. Now basically We don’t use white ones, because white ones give people a bad visual effect and may affect their performance, so they are all yellow now. In the past, seamed balls made of celluloid were used. Celluloid is a material that is flammable, explosive, not resistant to beating, and is also relatively fast. This time the ball was changed, it was supposed to be a plastic seamless ball. However, the patented technology of seamless balls was registered by European black merchants at a high price. The ITTF cannot afford the patented technology of seamless balls, so now all seam balls of new materials are used. Seamless balls may have to wait until patent protection is passed before they can be promoted. As for the purpose of changing the ball, it is called reducing pollution and being safer. In fact, it is to make the ball slower and spin weaker, and continue to suppress the dominance of the Chinese team.