What are the factors that affect the anti-ultraviolet properties of fabrics?

(1) Fabric structure: The fabric's loose thickness, tightness (coverage or porosity) and the original yarn structure, the number of fibers in the cross section, twist, hairiness, etc., have differences in the shielding effect of ultraviolet rays.

(2) Fiber types and dye types: Different fibers are dyed with dyes of different properties, and different dye molecular structures have different absorption of the spectrum.

(3) The effect of the color and amount of dyes: Even if the dyes of the same nature are dyed with different colors and the amount of dyes, the UV shielding performance of the fabric is different; generally speaking, the textiles of the same material have different performances. For dyeing with the same dye, the darker the color, the more it absorbs ultraviolet rays, and the better the shielding effect of ultraviolet rays. The ultraviolet protection performance of dark cotton cloth is better than that of light colors.

(4) The anti-ultraviolet performance of textiles is also affected by the fiber's own matrix and the organic or inorganic materials artificially attached to the fiber; natural fibers such as cotton and silk have low ultraviolet absorption capacity, so the anti-ultraviolet performance is poor, while wool is slightly better ; Synthetic fiber has a stronger ability to absorb ultraviolet rays than natural fiber.

(5) The effect of finishing: water and oil repellent finishing. On the one hand, the thickness of the fabric increases, and the porosity of the fabric will also decrease; on the other hand, the functional finishing agent itself may also increase the effect of shielding ultraviolet rays.