Abstract: An apparatus for manufacturing easy-to-open bags comprising a pair of feed rollers, at least one puncher disposed downstream of said feed rollers, upper and lower separating rollers disposed downstream of said puncher, tear string positioning member disposed downstream of said separating rollers, heat bonding means disposed downstream of tear string positioning means, bag making means disposed downstream of said heat bonding means and cutting means disposed downstream of said bag making means.

Abstract: An easy-to-open synthetic resin bag comprising: a bag body constituted by a laminated film formed by laminating several layers of synthetic resin film; a tear string bonded to part of an inner surface of the bag body corresponding to the opening thereof; and a tab formed at an end of the tear string; whereby pulling the tear string by the tab enables one side surface of the bag to be torn open, thereby allowing the bag to be opened. Also disclosed is a bag manufacturing apparatus capable of automatically bonding the tear string to the part of the inner surface of the bag body corresponding to the opening thereof when the bag body is being formed by employing the laminated film of the above kind.