Abstract: To understand the hygroscopic properties of bamboo shell fiber and provide theoretical basis for further developing and utilization studying bamboo shell. Characteristic curves of moisture adsorption and moisture liberation and hygroscopic expansion of bamboo shell fiber were obtained by testing under standard condition. Then the regression equation of the moisture regain to time and the rate of moisture absorption and moisture evaporation were derived during the moisture equilibrium at sorption side or moisture equilibrium at desorption side of bamboo shell fiber. The hygroscopicity of bamboo shell fiber is analyzed and compared with ramie fiber shell and cotton fiber. The results showed that: bamboo shell fiber has good moisture absorption and desorption performance property; Bamboo shell fiber initial absorption is faster, along with the extension of time moisture, moisture absorption rate of the fibers decay with exponential curve; the desorption rate of three fibers are relatively similar of three fibers. Wet hygroscopic expansion horizontal and vertical expansion of bamboo shell fiber are the largest, horizontal expansion is much larger than the longitudinal expansion.

Key words: bamboo shell fiber, hygroscopic, absorption and desorption rate, wet expansion