The eucalyptus-derived eco-material “Lyocell” is blended with cotton fiber. A deodorant substance is worked into this fiber that chemically eliminates the sources of ammonium gas (urine odor), acetate gas (sweat odor), and isovalerate gas (foot odor). It brings about an instant deodorizing effect. When the deodorant component of the Deo-thread comes into contact with foul air, neutralization occurs to eliminate the odors. Even after the neutralization is repeated many times, the effect remains almost permanently, without becoming saturated. In addition, the deodorant effect is hardly weakened by washing.