D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
D01C—CHEMICAL OR BIOLOGICAL TREATMENT OF NATURAL FILAMENTARY OR FIBROUS MATERIAL TO OBTAIN FILAMENTS OR FIBRES FOR SPINNING; CARBONISING RAGS TO RECOVER ANIMAL FIBRES
D01C1/00—Treatment of vegetable material
D01C1/02—Treatment of vegetable material by chemical methods to obtain bast fibres