How is the 'pigment dyeing' mentioned in the description different from regular dyeing?

Starting with the fabric, it is high-density 30s cotton, and pigment dyeing has been applied to it^[1]. 30s is a yarn count notation indicating the thickness of the yarn, where a higher number means a finer yarn. This means it is a fabric densely woven with fine yarn.

Pigment, namely pigment colorant, differs from dyes in how it produces color. While dyes dissolve in water and penetrate into the fibers, pigments are insoluble color particles that sit on the surface of the fibers and are held in place with a binder. Because the color sits on the outside without soaking into the inside, as you wear and wash it, the pigment gradually comes off starting from areas exposed to friction, and the color slowly fades. It is also common with this method that areas where yarn is prominent—such as where the collar folds, the ends of the sleeves, and the stitching on the front placket—brighten first, leaving a mottled texture on the surface.

We have not yet confirmed the care instructions provided by the brand. However, for garments colored with pigments, it is generally better to wash them inside out separately, briefly in cold water, and avoid bleach and vigorous wringing. It is safe not to wash them with light-colored clothes, as color bleeding may occur during the first few washes.