Hot fill containers with improved top load capabilities

A thin walled, blow molded, polyester container adapted to be filled with a liquid at a temperature elevated above room temperature, said container comprising:

• a mouth defining an opening into said container;
• a neck including sealing means formed at least partially thereon for receiving a closure cap to seal said container;
• a shoulder portion adjacent to said neck and extending generally downward and outward therefrom, said shoulder portion including a upper portion extending downward from said neck and generally increasing to a first diameter proceeding away from said mouth, a lower portion defining a second diameter being greater than said first diameter, and a reduced diameter portion located between and unitarily connecting said upper and lower portions, said reduced diameter portion extending circumferentially around said container and forming a recessed annular groove between said upper and lower portions, said reduced diameter portion having a diameter which is less than said second diameter and greater than that of said first diameter;
• at least three substantially upright ribs formed in said reduced diameter portion, said ribs being located such that no two ribs are in a common plane drawn through a longitudinal axis through said container and being hollow and extending longitudinally between said upper portion and said lower portion, said ribs reinforcing said reduced diameter portion increasing the top load capacity of said container, said ribs being equidistantly spaced around said reduced diameter portion and protruding radially outward from said reduced diameter portion;
• a side wall of generally tubular shape, said side wall being configured to accommodate a volumetric shrinkage of the liquid as a result of cooling of the liquid;
• and
• a bottom portion closing off said side wall and forming a base of said container.