Container with reinforced upper portion for receiving welded closure

A method of forming a plastic container with a longitudinal axis that extends through a center of an opening of the container comprising:

• providing a mold;
• and
• blow molding the container to include:
• an upper portion that defines the opening into the container;
• a sidewall portion that extends from the upper portion in a longitudinal direction parallel to the longitudinal axis;
• and
• a base portion that extends from the sidewall portion and that closes off the container, the base portion extending perpendicularly to the longitudinal axis,
• the upper portion including a rim member, a neck member that extends in the longitudinal direction away from the rim member, and a shoulder member that extends from the neck to the sidewall portion, the shoulder member extending at an acute angle relative to a transverse plane that is substantially perpendicular to the longitudinal axis;
• a first side and a second side that extends parallel to the first side;
• a third side and a fourth side that extends parallel to the third side, the third and fourth sides extend perpendicular to the first and second sides and are arranged at opposite ends of the first and second sides;
• a plurality of first reinforcing members evenly spaced apart along the first side, each one of the first reinforcing members protecting outwardly from the neck member and extending in the longitudinal direction between the rim member and the shoulder member;
• a plurality of second reinforcing members evenly spaced apart along the second side, each one of the second reinforcing members protecting outwardly from the neck member and extending in the longitudinal direction between the rim member and the shoulder member;
• a first rib protecting outwardly from the neck member at the third side and extending longitudinally in a transverse direction that is perpendicular to the longitudinal axis, a single side reinforcement member protects outward from the neck member at the third side and is centered along a length of the first rib;
• and
• a second rib protecting outwardly from the neck member at the fourth side and extending longitudinally in a transverse direction that is perpendicular to the longitudinal axis, a single side reinforcement member protects outward from the neck member at the fourth side and is centered along a length of the second rib;
• wherein the container is rectangular.