1) Increment ratio of strength of a paper yarn by twisting is so bigger than that of cellophane that the Japanese paper yarn could be considered a yarn made by twisting fibers arranged lengthwise.
2) The bigger the ratio (P_m/P_b) of lengthwise-machine direction-strength (P_m) to breadthwise strength (P_b) of a raw paper becomes, in other words fibers are better ordered lengthwise, the stronger yarns made by twisting raw papers become.
3) However strength of yarns depends more upon thinness and softness of raw papers, and length, flexibility and strength of raw-fiber, than upon P_m/P_b.