Extrusion blow molded pet container having superior column strength
View Patent ↗An extrusion blowmolded PET container having superior top load strength characteristics includes a sidewall having an outer surface, and an inner surface that defines an interior space. The sidewall is fabricated from a material that includes extrudable PET. The sidewall is shaped to define a bottom portion, a finish portion and a main body portion. The finish portion has an opening defined therein that is in communication with the interior space. The main body portion has a neck surface, a shoulder surface and a fillet that is defined between the neck surface and the shoulder surface. The neck surface forms a first angle with respect to a longitudinal axis of the container that is substantially within a range of about 2° to about 20°, and the fillet has an average radius of curvature that is substantially within a range of about 15 mm to about 55 mm. The container is preferably fabricated using an extrusion blowmolding process.
1. An extrusion blowmolded PET container having superior top load strength characteristics, comprising:
a sidewall having an outer surface and an inner surface that defines an interior space, the sidewall being fabricated from material comprising extrudable PET, and wherein the sidewall is shaped to define
a bottom portion;
a finish portion having an opening defined therein that is in communication with the interior space; and
a main body portion, the main body portion having a neck surface, a shoulder surface and a fillet that is defined between the neck surface and the shoulder surface, wherein the neck surface forms a first angle with respect to a longitudinal axis of the container that is within a range of 2° to 20°, and wherein the fillet has an average radius of curvature that is within a range of 15 mm to 55 mm.
2. An extrusion blowmolded PET container according to claim 1 , wherein the first angle is further within a range of 3° to 14°.
3. An extrusion blowmolded PET container according to claim 2 , wherein the first angle is further within a range of 4° to 8°.
4. An extrusion blowmolded PET container according to claim 1 , wherein the fillet has an average radius of curvature that is within a range of 17 mm to 40 mm.
5. An extrusion blowmolded PET container according to claim 4 , wherein the fillet has an average radius of curvature that is within a range of 20 mm to 28 mm.
6. An extrusion blowmolded PET container according to claim 1 , wherein the shoulder surface forms a second angle with respect to a longitudinal axis of the container that is within a range of 35° to 65°.
7. An extrusion blowmolded PET container according to claim 6 , wherein the second angle is within a range of 40° to 60°.
8. An extrusion blowmolded PET container according to claim 7 , wherein the second angle is within a range of 45° to 55°.
9. An extrusion blowmolded PET container according to claim 1 , wherein the main body portion has a handle portion defined therein and a finger access opening defined adjacent to the handle portion.
10. An extrusion blowmolded PET container according to claim 9 , wherein the handle portion has a hollow interior that is part of the interior space of the container.
11. An extrusion blowmolded PET container according to claim 9 , wherein the finger access opening has a concave upper surface.
12. An extrusion blowmolded PET container according to claim 11 , wherein the concave upper surface includes a first curved portion that is proximate to the longitudinal axis of the container and a second curved portion that is proximate to the handle portion, and wherein the first curved portion has a radius of curvature that is greater than a radius of curvature of the second curved portion.
13. An extrusion blowmolded PET container according to claim 9 , wherein the finger access opening has a maximum height that is within a range of-75 mm to 120 mm.
14. An extrusion blowmolded PET container according to claim 13 , wherein the finger access opening has a maximum width that is within a range of-13 mm to 35 mm.
15. An extrusion blowmolded PET container according to claim 1 , wherein said sidewall has a thickness in the main body portion that is within a range of 0.35 mm to 2 mm.
16. An extrusion blowmolded PET container according to claim 15 , wherein said sidewall has a thickness in the main body portion that is within a range of 0.5 mm to 1.2 mm.
17. An extrusion blowmolded PET container according to claim 16 , wherein said sidewall has a thickness in the main body portion that is within a range of 0.65 mm to 0.9 mm.
18. A method of making a PET container, comprising:
continuously extruding a parison of a plastic material comprising PET;
capturing a portion of the parison in a mold;
inflating the captured portion of the parison against an interior of the mold in order to form a PET container having a main body portion with a neck surface, a shoulder surface and a fillet that is defined between the neck surface and the shoulder surface, wherein the neck surface forms a first angle with respect to a longitudinal axis of the container that is within a range of 2° to 20°, and wherein the fillet has an average radius of curvature that is-within a range of 15 mm to 55 mm; and
removing the container from the mold.
19. A method of making a PET container according to claim 18 , wherein the first angle is further within a range of 3° to 14°.
20. A method of making a PET container according to claim 19 , wherein the first angle is further within a range of 4° to 8°.
21. A method of making a PET container according to claim 18 , wherein the fillet has an average radius of curvature that is within a range of 17 mm to 40 mm.
22. A method of making a PET container according to claim 21 , wherein the fillet has an average radius of curvature that is within a range of 20 mm to 28 mm.
23. A method of making a PET container according to claim 18 , wherein the shoulder surface forms a second angle with respect to a longitudinal axis of the container that is within a range of 35° to 65°.
24. A method of making a PET container according to claim 23 , wherein the second angle is within a range of 40° to 60°.
25. A method of making a PET container according to claim 24 , wherein the second angle is within a range of 45° to 55°.
26. A plastic container, comprising:
a sidewall having an outer surface and an inner surface that defines an interior space, the sidewall being fabricated from a plastic material, and wherein the sidewall is shaped to define
a bottom portion;
a finish portion having an opening defined therein that is in communication with the interior space; and
a main body portion, the main body portion having a handle portion defined therein and a finger access opening defined adjacent to the handle portion, the finger access opening having a concave upper surface, and wherein the concave upper surface includes a first curved portion that is proximate to the longitudinal axis of the container and a second curved portion that is proximate to the handle portion, wherein the first curved portion has a radius of curvature that is greater than a radius of curvature of the second curved portion and wherein the second radius of curvature is within a range of 3 mm to 48 mm.
27. A plastic container according to claim 26 , wherein the first radius of curvature is within a range of 5 mm to 50 mm.
28. A plastic container according to claim 26 , wherein a ratio R 2 /R 3 of the first and second radii is within a range of 1.05 to 18.