PROBLEM TO BE SOLVED: To enable exertion of excellent deodorizing and antibacterial effects, etc. by using bamboo vinegar and a green bamboo extract in processing of thread and fiber cloth and also thereby prevent deterioration of texture and color loss.SOLUTION: Bamboo vinegar obtained by collecting and cooling flue gas generated in production of bamboo charcoal is purified by a low-temperature distillation method or a standing method to obtain bamboo vinegar of a Ph of 3.0-5.0, and the bamboo vinegar is diluted and left standing to an odorless state. A green bamboo extract of a Ph of 5.0-5.5 obtained by boiling green bamboo and bamboo grass is subjected to a Ph adjustment with acidic water to prepare a green bamboo extract of Ph of 3.0-5.0, and the bamboo extract is diluted and left standing to an odorless state. These liquids are used in processing of Japanese paper-made thread and fiber products.
