Bamboo fabric is highly absorbent. The DIY diaper crowd use it.
Why "rayon"? Because that's what bamboo fabrics are, chemically reprocessed cellulose. FWIW (1.5 cents, I guess).Rayon is a versatile fiber and has the same comfort properties as natural fibers. It can imitate the feel and texture of silk, wool, cotton and linen. The fibers are easily dyed in a wide range of colors. Rayon fabrics are soft, smooth, cool, comfortable, and highly absorbent, but they do not insulate body heat, making them ideal for use in hot and humid climates.