Disposable sanitary article and process for providing such article with elastic members associated with leg-openings

A process for attaching elastic members associated with leg-openings to a disposable sanitary article which comprises a liquid-pervious topsheet, a liquid-impervious backsheet and a liquid-absorbent panel disposed between said topsheet and said backsheet to define a front waist region, a rear waist region and a crotch region extending between said front and rear waist regions, and said pair of leg-openings being defined at transversely opposite side edge portions of said article, comprising the steps of:

• (a) feeding a continuous web having transversely opposite side edge portions forward and coating said transversely opposite side edge portions with an adhesive agent to form first adhesive zones and second adhesive zones continuously extending in a longitudinal direction of said continuous web;
• and
• (b) feeding first and second elastic members associated with said leg-openings continuously extending in said longitudinal direction and securing sections of said elastic members placed upon said first and second adhesive zones to these zones so that said first and second elastic members extend across said first and second adhesive zones to describe a pair of continuous waveforms in a relationship of lateral symmetry, each of which is convex inward transversely beyond each of innermost side edges of said first and second adhesive zones and then convex outward transversely beyond each of outermost side edges of said first and second adhesive zones, each of said waveforms is further convex in a front or rear half of said zone in which each of the waveforms becomes convex inward transversely extending from an imaginary X-axis bisecting a longitudinal dimension of said zone than said rear or front half of said zone, said first elastic members associated with the one leg-opening lying on said first adhesive zone and said second elastic members associated with the other leg-opening are secured to said continuous web along these adhesive zones and the sections of the first and second elastic members which are convex inward and outward transversely beyond said first and second adhesive zones contract to be converged substantially into single bundles so as to move toward said first and second adhesive zones and are secured to said continuous web.