Materials used traditionally in Japan to make brushes used to be the hair of animals like deer, raccoon dogs, and horses found in Japan. However, today imported animal hair such as that of weasels, goats, and rabbits is used. To ensure that the hair can absorb ink well, the hair is first treated with ash to remove oil. It takes great craftsmanship to blend the different types of hair depending on the purpose of the brush. This step is called kegumi and the blend can greatly influence the quality of the brush.