100% Soy Fibre. 100% Soy Fibre. Extremely clean combed top in "natural" ivory. Staple length of 4 to 5 inches. SoySilk® is a registered trademark, but our supply is a very similar product from another manufacturer. It turns out that what we have been selling for years is the bleached version of soy fibre. Lustrous and soft, soy fibre is enjoying great popularity by itself or in blends with wool and other fibres. Very well-suited to summer wear since it's great at absorbing moisture. Soy fibre is manufactured from the waste pulp that remains after soybeans have been pressed for oil. Surprisingly, though it comes from plants, soy fibre has more in common with protein fibres in the dyepot. It takes colour beautifully using acid dyes and will respond well to the usual natural dye premordants that are used on animal fibres.