The former report show that the crinkle mechanism of crepe was a phenomenon of torsional buckling of yarns. If the elastic curve (the number and shape of helixes) of hard twisted yarns and the phase difference between contiguous hard twisted yarns were decided, the shape of crimps were determined.
And analysis for phase difference between hard twisted yarns in general crepe model was carried out, which uses hard twisted yarns for weft. The model was assumed that the phase difference was decided so that the deformation energy would be minimized by elongating warps in a reticulate fabric where there is no sliding between warps and wefts at their crossings. As the result, it was found that the phases became indentical when yarns twisted in the same direction were contiguous, and that when yarns twisted in the opposite directions were contiguous the phase difference depended upon the shapes of helixes. When the helixes were crushed to vertically to the fabric surface, the phase became identical, but when the helixes were crushed to horizontally to the surface or the helixes could be regarded as circles, the phase shifted by half.
Crepe were made by using silk and cotton yarns, in order to compare with the model fabric. From the comparison, it confirmed that the result can explain the phase difference between contiguous hard twisted yarns in crepe.

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