Method for improving color depth and light fastness of natural dye-dyed fabric

The invention relates to a method for improving color depth and light fastness of a natural dye-dyed fabric. The method utilizes an association effect between polyvinylpyrrolidone and natural dye molecules to improve the color depth of the natural dye-dyed fabric; a polyhydric alcohol method is adopted to generate nano ZnO on the surface of the fabric in situ; the excellent anti-ultraviolet performance of nano ZnO is used for improving the light fastness of the natural dye-dyed fabric. With the adoption of the method, the color depth and the light fastness of the natural dye-dyed fabric are obviously improved and the washing-resisting performance of the natural dye-dyed fabric is good.