Fluid product reservoir and method

A method of ultrasonically welding together first and second low grade thermoplastic members, comprising the steps of:

• locating the first and second members in mating relationship at the intended weld location;
• and
• applying ultrasonic energy to the first member by contact with an energized ultrasonic welding horn at a location remote from the intended weld location, and applying ultrasonic energy substantially simultaneously to the second member by contact with an energized ultrasonic welding horn at a location remote from the intended weld location to weld together the first and second members at the intended weld location.

A method of ultrasonically welding together first and second thermoplastic members having first edges adapted to be located in mating relationship at an intended weld location, and having second portions in adjacent relationship and remote from the first edges when the first edges are in mating relationship, comprising the steps of:

• locating the first and second thermoplastic members with the first edges in mating relationship;
• and
• applying ultrasonic energy to the first member by contact with an energized ultrasonic welding horn at the second portion of the first member and applying ultrasonic energy to the second member by contact with an energized ultrasonic welding horn substantially simultaneously at the second portion of the second member to weld together the first and second members at the intended weld location.