Patent ID: 6090029
Filing Date: 2000-07-18
Classification: B31B,B65D,Y10S

Abstract:
A method of constructing a rigid spout fitment in a flexible and collapsible liquid impervious liner made of flexible thermoplastic sheet material adapted to be received in a rigid box or a flexible and collapsible bulk bag having an upright orientation in use and side and bottom walls, said liner having side, top and bottom walls and fill and discharge openings, said method comprising the steps of;(a) providing a self-supporting rigid spout made of thermoplastic material and having a generally cylindrical tube adapted to extend through one of the liner openings in one of the liner walls and being openable at opposite ends of the tube, one of the tube ends being adapted to be disposed interiorly of the one liner wall and the other of the tube ends adapted to be disposed exteriorly of the one liner wall, the spout also having an external rigid flange base adjacent the one interiorly disposed tube end extending radially outwardly in encircling relation to the tube,(b) providing a first backing piece of a flexible and liquid impervious plastic sheet material and disposing the same against a second surface of the flange base disposed on the opposite side of the flange base from the first flange base surface with the first backing piece radially encompassing the one tube end and having a marginal portion protruding radially outwardly beyond the peripheral edge of the flange base,(c) forming a separate first annular heat seal between the first backing piece and the flange base second surface in a first annular weld zone and spaced radially outwardly from the tube to thereby attach the first backing piece to the flange base,(d) inserting the spout other end, with the first backing piece attached to the flange base, through the one liner fitment opening to thereby dispose an interior surface of the liner against the flange base first surface and to dispose the marginal portion of the first backing piece against the liner interior surface,(e) permanently affixing the spout to the liner by a separate and circumferentially continuous second annular heat seal formed in a second annular weld zone between the first surface of said flange base and the interior surface of the liner and encompassing the opening of the liner, the second heat seal being spaced radially outwardly from the first heat seal, and(f) forming a separate and circumferentially continuous third annular heat seal between the first backing piece marginal portion and the liner interior surface in a third annular weld zone and spaced radially outwardly from the second heat seal and spaced radially from the first and second heat seals.