Direct dyes are a type of coloring agent used primarily in the textile industry. They are water-soluble and can bond directly to the fabric fibers without the need for a mordant, which is a substance that helps fix the dye to the material. This makes them easy to use and ideal for dyeing natural fibers like cotton and wool. These dyes are known for their vibrant colors and good wash fastness, meaning they resist fading when washed. However, they may not be as lightfast as some other dye types, which means they can fade when exposed to sunlight. Overall, direct dyes are popular for their simplicity and effectiveness in achieving bright hues.