| 摘要 |
Shirred tubular material comprising a plurality of outer folds arranged along at least two parallel and two counter-directional parallel, longitudinal extending, crisscrossing helixes and inner folds connecting opposing points of diamond shapes defined by said outer folds is disclosed together with a method for its preparation comprising repeatedly applying a set of shirring forces, each of the forces in the set being simultaneously at circular circumferential equally spaced positions along a plurality of equidistant helical lines within the periphery of said tubular material to shirr such material. |
