Preform base and method of making a delamination and crack resistant multilayer container base
AssigneeGraham Packaging Company, L.P.
InventorTapan Y. Patel
Life of this patent
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Abstract
Molded preform for blow molding a plastic container for pressurized applications, the preform having a base with a multilayer wall for forming a delamination and crack resistant multilayer footed container base. The preform base forming region has an end cap portion with a non-spherical inner wall, including a flattened central section joined by arcuate corner sections to a generally cylindrical outer section. The inner wall sections provide a varying end cap thickness profile which enhances orientation in select portions of the footed container base for improved performance and/or lightweighting of the container base.
Claims42
A plastic container for pressurized applications having a crack resistant multilayer footed base, the container formed by a method comprising:
- providing a molded preform having an end cap region including a multilayer wall, the end cap region including a generally spherical outer surface and a relatively flattened central inner surface providing an end cap thickness profile which includes extending radially outwardly from a central longitudinal axis of the preform:
- a central thickened end cap region;
- an intermediate end cap region which is thinner than the central region;
- and
- an outer end cap region which is thicker than the intermediate region;
- and
- blow molding the preform to form a plastic container for pressurized applications having a delamination and crack resistant multilayer footed base.
A molded preform for blow molding a plastic container for pressurized applications, the preform having a base with a multilayer wall for forming a delamination and crack resistant multilayer footed container base, the base comprising:
- a generally cylindrical upper base portion;
- an end cap portion having a generally spherical outer wall and a nonspherical inner wall, the nonspherical inner wall having a flattened central section joined by arcuate corner sections to a generally cylindrical outer section forming an extension of the cylindrical upper base portion, wherein the inner wall sections respectively provide a varying end cap thickness profile comprising:
- a central thickened end cap region;
- an intermediate end cap region which is thinner than the central region;
- and
- an outer end cap region which is thicker than the intermediate region.
An improved injection-molded preform for blow molding a single-use plastic beverage container for pressurized liquids having a multilayer footed base, the preform having an end cap region including a multilayer wall with a layer of a polyester material and an adjacent layer of a different polyester or nonpolyester material, the improvement comprising:
- providing a non-spherical preform end cap region to form a delamination and crack resistant pressurized container base of reduced weight, wherein the non-spherical end cap region has a thickness which includes:
- a relatively flattened central inner surface forming a central thickened end cap region;
- an intermediate region surrounding the central region which is thinner than the central region;
- and
- an outer end cap region surrounding the intermediate region which is thicker than the intermediate region.
A method of making a delamination and crack resistant multilayer footed base of a plastic container for pressurized applications, the method comprising:
- providing a molded preform having an end cap region including a multilayer wall, the end cap region including a generally spherical outer surface and a relatively flattened central inner surface providing an end cap thickness profile which includes extending radially outwardly from a central longitudinal axis of the preform:
- a central thickened end cap region;
- an intermediate end cap region which is thinner than the central region;
- and
- an outer end cap region which is thicker than the intermediate region;
- and
- blow molding the preform to form a plastic container for pressurized applications having a delamination and crack resistant multilayer footed base.
Dependencies are inferred from the claim text.