Natural Bast Fibers are strong, cellulosic fibers obtained from the phloem or outer bark of jute, kenaf, flax and hemp plants.
They are annually renewable crops, growing in 90 to 100 days. The fiber is around the outside of the plant and comprises one-third of the weight. The center (core) resembles balsa wood and has many uses, including animal bedding and oil absorbants. In India and Bangladesh, it is mostly used as firewood.
Unlike synthetic fibers, bast fibers are made up of bundles of fibers. These bundles are broken down mechanically or chemically to achieve the fineness required. The degree of this breakdown, in turn, dictates their end use.