To provide a production method of a nonwoven bag and a nonwoven sheet, having no color irregularity and cost advantage, and to provide the nonwoven bag and the nonwoven sheet.
The production method of nonwoven bags different in color tone of the outer surface and the inner surface comprises, a step (1) for preparing a nonwoven planar substance by supplying many fibers compounded with a colorant of one color tone on a belt conveyor, then passing the formed web between hot-rolls to press-weld the fibers each other and winding the obtained to form the nonwoven planar substance, and, a step (2) for cutting the nonwoven planar substance produced in the step (1) to be desired size and processing the obtained to be bag-like by sewing or welding the obtained. In the production method, by previously preparing a nonwoven planar substance compounded with another colorant of different color tone from that of the above colorant and having desired thickness and passing the nonwoven planar substance together with the web when passing the web between the hot-rolls, the nonwoven planar substance of two-layer structure is produced.
MIWA SHINICHIRO
Miyazaki Yoshio
Mitsuo Tateishi
Toshio Nakamura
Tsutomu Kato
Kaoru Onozuka
High Masahiro