Thioindigo is widely used in the textile industry as a vat dye, particularly for coloring cellulosic fibers like cotton, linen, and rayon. Its vibrant shades, especially in blues and reds, and excellent lightfastness make it suitable for producing long-lasting and bright colors in fabrics. Additionally, it is employed in the manufacturing of inks and pigments for various printing applications, where color stability and durability are essential. In some cases, thioindigo is also utilized in organic synthesis as an intermediate for creating more complex chemical compounds. Its versatility and strong coloring properties make it a valuable specialty chemical in various industrial processes.