| 摘要 |
PROBLEM TO BE SOLVED: To obtain an extracting filter or bag which has sufficient shape retention property, also feels soft, and is excellent in extraction property wherein ultrasonic or heat-sealing fusion is easy by using a double-structured polyester-based fiber comprising a relatively hard core component and a relatively soft sheath component and by scouring and heat-treating the fiber at a specific temperature. SOLUTION: A fabric, a knitted item or an unwoven product using a double- structured fiber comprising a homo polyester molecule core component and a polyester molecule sheath component including terephthalic acid and isophthalic acid, which has a melting point lower than that of the homo polyester molecule by at least 100 deg.C and is softer that the homo polyester molecule wherein a ration of the core components is 50 vol.% or more, and 75 vol.% or less is scoured at 60 deg.C or lower. Thereafter, it is subjected to heat treatment at 100 to 130 deg.C to manufacture an extraction filter and bag where intersections of threads are not fused. Thus retention property of a three-dimensional form is excellent, elastic recovery is easy when deforming, soft feeling can be obtained when touched by fingers, drainability and an appearance is good, and further fusing in making a bag is easy. |
