LIGHTWEIGHT BOTTLE

Description

BACKGROUND

1. Field of the Invention

The present invention generally relates to lightweight containers, and more specifically to lightweight, blow molded plastic containers. Even more specifically, the invention relates to lightweight bottles for housing liquid or granular/powder material, having a spout or mouth for receiving a cap or closure, and exhibiting both reduced material usage and improved top load capabilities.

2. Description of Related Art

Blow molded plastic containers, of the bottle, jug and jar varieties, are widely used in the beverage, food, personal care, medical, pharmaceutical, household, motor oil, automotive and industrial markets and are available in a wide variety of shapes and volumes. Initially, containers were provided as either cylindrical containers with centrally oriented spouts or cylindrical containers with offset spouts. Cylindrical containers, while having various structural and manufacturing advantages, are not efficient when packaged for shipping on standard sized pallets. When multiple containers are packaged for shipping, open or void spaces are present between the adjacent containers, as well as the packaging, such as the walls of a box. More recently, such containers have been provided as either rectangular containers with centrally oriented spouts or rectangular containers with offset spouts. Rectangular containers are much more efficiently packaged because the void space between adjacent individual containers is significantly reduced. Accordingly, rectangular shaped containers are currently the most common, particularly, but not exclusively, in the United States.

In manufacturing the above mentioned plastic containers, typically, a high density polyethylene (HDPE) material is used in an extrusion blow molding process. In producing the containers, a significant portion of the overall cost of the container is a direct result of the amount of plastic resin used to form the container. Efforts to reduce the amount of plastic resin, however, are challenging.

One challenge is for the container to withstand industry standard or company specific top load requirements, testing of which is conducted under ASTM D2659-11. Minimum top load requirements ensure that the container will withstand the expected forces experienced during filling, capping, transporting and warehouse stacking. As an example, typical weights and top load capabilities of today's rectangular, off-set neck, one quart/one liter (1 Qt/1 L) motor oil containers are in the range of about 48 grams to 56 grams HDPE and about 45 to 65 lbf of top load (unvented and unfilled) capability. Reductions in the amount of plastic used in a given container are known to translate to a reduction in the top load capabilities of the container.

Since millions of containers are produced annually, it will be readily appreciated that any reduction in the amount (weight) of the plastic used to form the container, by even a few percentage points, and which does not compromise the container's top load capability, translates into enormous cost saving to the manufacturer.

SUMMARY

In overcoming the various drawbacks and limitations of the related art, the present invention provides a container for a pourable material that allows for reducing the weight of the container while retaining or improving high top load capabilities of the container.

Accordingly, in one aspect the invention provides a bottle for containment of a pourable material in which the bottle includes a spout defining an opening into a top end the bottle, a base located opposite of the spout and closing of a bottom end of the bottle, a hollow body defined about a central axis extending between the top and bottom ends of the bottle, and a transition section located between and connecting the body to the spout. In a transverse cross-section taken in a plane perpendicular to the central axis, the body has an elongated rectangular shape that is defined by four sidewalls and four corners. The four sidewalls include first and second major side walls and first and second minor sidewalls. Each of the four corners is defined by two rounded sub-corners and an intermediate wall located therebetween. A transverse axis is defined between the midpoints of the first and second minor sidewalls in the plane of the transverse cross-section. A first normal having a first length is defined in the plane of the transverse cross-section from the midpoint of one of the intermediate walls to an intersection point on the transverse axis, and a second normal having a second length is defined in the plane of the transverse cross-section from the midpoint of the first minor sidewall located adjacent to said intermediate wall to the intersection point, and the first length is substantially the same as the second length.

In another aspect, the ratio of the first length to the second length is less than 1.100.

In a further aspect, the ratio of the first length to the second length is in the range of 0.900 to 1.100.

In an additional aspect, the ratio of the first length to the second length is in the range of 0.990 to 1.100.

In yet another aspect, the ratio of the first length to the second length is in the range of 0.990 to 1.064.

In still a further aspect, a third normal having a third length is defined in the plane of the transverse cross-section from the midpoint of another one of the intermediate walls adjacent to said first minor sidewall to the intersection point, the third length being substantially the same as the second length.

In an additional aspect, a fourth normal having a fourth length is defined in the plane of the transverse cross-section from the midpoint of a further one of the intermediate walls, located adjacent to the second minor sidewall, to a second intersection point; a fifth normal having a fifth length is defined in the plane of the transverse cross-section from the midpoint of the second minor sidewall to the second intersection point. The fourth length is substantially the same as the fifth length and is substantially the same as the first length. A sixth normal having a sixth length is defined in the plane of the transverse cross-section, from the midpoint of an additional one of the intermediate walls located adjacent to the second minor sidewall to the second intersection point. The sixth length is substantially the same as the fourth length.

In still another aspect, a fourth normal having a fourth length is defined in the plane of the transverse cross-section from the midpoint of a further one of the intermediate walls, located adjacent to the second minor sidewall, to a second intersection point; a fifth normal having a fifth length is defined in the plane of the transverse cross-section from the midpoint of the second minor sidewall to the second intersection point; the fourth length is substantially the same as the fifth length and the fourth length is different from the first length; a sixth normal having a sixth length is defined in the plane of the transverse cross-section from the midpoint of an additional one of the intermediate walls, located adjacent to the second minor sidewall, to the second intersection point; and wherein the sixth length is substantially the same as the fourth length.

In yet a further aspect, a third normal having a third length is defined in the plane of the transverse cross-section from the midpoint of another one of the intermediate walls, located adjacent to the first minor sidewall, to a second intersection point; and a fourth normal having a fourth length is defined in the plane of the transverse cross-section from the midpoint of the first minor sidewall to the second intersection point. The third length being substantially the same as the fourth length and being different from the first length.

In an additional aspect, a third normal having a third length is defined in the plane of the transverse cross-section from the midpoint of another one of the intermediate walls, located adjacent to the second minor sidewall, to a second intersection point; and a fourth normal having a fourth length is defined in the plane of the transverse cross-section from the midpoint of the second minor sidewall to the second intersection point. The third length is substantially the same as the fourth length and as the second length.

In another aspect, a fifth normal having a fifth length is defined in the plane of the transverse cross-section from the midpoint of a further one of the intermediate walls, located adjacent to the first minor sidewall, to a third intersection point; a sixth normal having a sixth length is defined in the plane of the transverse cross-section from the midpoint of the first minor sidewall to the third intersection point; the fifth length is substantially the same as the sixth length and the fifth length is different from the first length; a seventh normal having a seventh length is defined in the plane of the transverse cross-section from the midpoint of an additional one of the intermediate walls, located adjacent to the second minor sidewall, to a fourth intersection point; and wherein the seventh length is substantially the same as the fifth length.

In a further aspect, a third normal having a third length is defined in the plane of the transverse cross-section from the midpoint of another one of the intermediate walls, located adjacent to the second minor sidewall, to a second intersection point, and a fourth normal having a fourth length is defined in the plane of the transverse cross-section from the midpoint of the second minor sidewall to the second intersection point. The third length is substantially the same as the fourth length and being different than the first length.

In an additional aspect, in the plane of the transverse cross-section, the first endwall defines a first width and the second endwall defines a second width, the first width being less than the second width.

In still another aspect, the plane of the transverse cross-section, the first endwall defines a first width and the intermediate walls adjacent thereto defines a second width, the first width being substantially the same as the second width.

In yet a further aspect, in the plane of the transverse cross-section, the first endwall defines a first width and the intermediate walls adjacent thereto respectfully define second and third widths, the first width being less than at least one of the second and third widths.

In an additional aspect, the second width is the same as the third width.

In another aspect the invention provides a bottle for containment of a pourable material. The bottle includes a spout defining an opening into a top end the bottle, a base located opposite of the spout and closing of a bottom end of the bottle, a hollow body defined about a central axis and extending between the top and bottom ends of the bottle, and a transition section between and connecting the body to the spout. In a transverse cross-section taken in a plane perpendicular to the central axis, the body has an elongated shape with least two sidewalls and a corner therebetween. The two sidewalls including a major side wall and a minor sidewall with the major sidewall having a width dimension in the transverse cross-section that is greater than the width dimension of the minor sidewall in the transverse cross-section. The corner is defined by an intermediate wall between two corner transitions. The corner transitions connect the intermediate wall respectively to the major wall and to the minor wall. In the plane of the transverse cross-section, a transverse axis is defined perpendicular from the midpoint of the width of the minor sidewall. A first normal having a first length is defined in the plane of the transverse cross-section from the midpoint of the intermediate wall to an intersection point on the transverse axis, and a second normal having a second length is defined in the plane of the transverse cross-section from the midpoint of the minor sidewall to the intersection point. The first length is substantially the same as the second length.

In still another aspect, the ratio of the first length to the second length is less than 1.100.

In yet a further aspect, the ratio of the first length to the second length is in the range of 0.900 to 1.100.

In an additional aspect, the ratio of the first length to the second length is in the range of 0.990 to 1.100.

In another aspect, the ratio of the first length to the second length is in the range of 0.990 to 1.064.

In a further aspect, the major sidewall is a first major sidewall, the corner is a first corner, the intermediate wall is a first intermediate wall and the intersection point is a first intersection point, the elongated shape further including a second major side wall generally opposing the first major sidewall and a second corner being defined by a second intermediate wall between two second corner transitions, the two second corner transitions connecting the second intermediate wall respectively to the second major wall and to the minor wall; a third normal having a third length is defined in the plane of the transverse cross-section from the midpoint of the second intermediate wall to a second intersection point on the transverse axis; and a fourth normal having a fourth length is defined in the plane of the transverse cross-section from the midpoint of the minor sidewall to the second intersection point, the third length being substantially the same as the fourth length.

In still a further aspect, the first intersection point and the second intersection point are defined at a common location on the transverse axis.

In an additional aspect, the first intersection point and the second intersection point are defined at different locations along the transverse axis.

In yet another aspect, the minor sidewall is a first minor sidewall, the corner is a first corner, the intermediate wall is a first intermediate wall and the intersection point is a first intersection point, the elongated shape further including a second minor sidewall generally opposing the first minor sidewall and a second corner being defined by a second intermediate wall between two second corner transitions. The two second corner transitions connecting the second intermediate wall respectively to the second minor wall and to the major wall. A third normal having a third length is defined in the plane of the transverse cross-section from the midpoint of the second intermediate wall to a second intersection point on the transverse axis. A fourth normal having a fourth length is defined in the plane of the transverse cross-section from the midpoint of the minor sidewall to the second intersection point, the third length being substantially the same as the fourth length.

In a further the first length is the same as the third length and the second length is the same as the fourth length.

In an addition aspect, the first length is different than third length and the second length is different than the fourth length.

Further objects, features and advantages of this invention will become readily apparent to persons skilled in the art after a review of the following description, including the claims, and with reference to the drawings that are appended to and form a part of this specification.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevational view of a container embodying the principles of the present invention.

FIG. 2 is a left side elevational view of the container seen in FIG. 1.

FIG. 3 is a right side elevational view of the container seen in FIG. 1.

FIG. 4 is a top plan view of the container seen in FIG. 1.

FIG. 5 is a cross-sectional view of the container seen in FIG. 1, generally taken along line 5-5 in FIG. 1.

FIG. 6 is a cross-sectional view of the container seen in FIG. 1, generally taken along line 6-6 in FIG. 1.

FIG. 7 is a graph presenting a mapping of the wall thickness of a conventional container and the container seen in FIG. 1.

FIG. 8 is a schematic representation comparing the wall thicknesses, at various locations, of a conventional 1 Qt/1 L container against those of a 1 Qt/1 L container according to the present invention.

FIG. 9 is a front elevational view of 2.5 gallon/10 liter (2.5 Gal/10 L) container embodying the principles of the present invention.

FIG. 10 is a cross-sectional view generally taken along line 10-10 in FIG. 9.

FIG. 11 is a graph presenting a mapping of the wall thickness of a conventional 2.5 Gal/10 L container and the container seen in FIG. 9.

FIG. 12 is a schematic representation comparing the wall thicknesses, at various locations, of a conventional 2.5 Gal/10 L container against those of a 2.5 Gal/10 L container according to the present invention.

FIG. 13 is a front elevational view of an additional container embodying the principles of the present invention.

FIG. 14 is a left side elevational view of the container seen in FIG. 13.

FIG. 15 is a right side elevational view of the container seen in FIG. 13.

FIG. 16 is a top plan view of the container seen in FIG. 13.

FIG. 17 is a bottom plan view of the container seen in FIG. 13.

FIG. 18 is a line representation of the perimeter of the container seen in FIG. 13, the perimeter of a variation of the container seen in FIG. 13, and the perimeter of a symmetrical container in accordance with the principles of the present invention.

FIG. 19 is a bottom view of symmetrical container according to the present invention overlaid with a line representation of the perimeter of another variation of a container according the present invention.

FIG. 20 is a bottom view of symmetrical container according to the present invention overlaid with a line representation of the perimeter of another variation of a container according the present invention.

DETAILED DESCRIPTION

As used in the description that follows, directional terms such as “upper” and “lower” are used with reference to the orientation of the elements as presented in the figures. Accordingly, “upper” indicates a direction toward the top of the figure and “lower” indicates a direction toward the bottom of the figure. The terms “left” and “right” are similarly interpreted. The terms “inward” or “inner” and “outward” or “outer” indicate a direction that is generally toward or away from a central axis of the referred to part, whether or not such an axis is designated in the figures. An axial surface is therefore one that faces in a direction along the central axis. A radial surface therefore faces radially, generally away from or toward the central axis.

Referring now to the drawings, a blow molded plastic container embodying the principles of the present invention is generally illustrated in FIG. 1 and designated at 10. The containers discussed herein are of the bottle, jug and jar varieties but for simplicity are simply referred to as a container. The container 10, which is formed by blow molding and, in particular, extrusion blow molding, incorporates novel structural features that provide enhanced strength and rigidity to the container 10. As a result, for like-sized containers, the present container 10 can be formed from a reduced amount of plastic resin, while being able to provide a similar or greater top load capacity.

As used in the initial discussion and comparisons of the present disclosure, both the conventional containers and the present container are containers intended to hold about one quart (32 fl. oz.)/one liter of liquid and have an overflow volume of about 36.9+/−0.5 fl. oz. The containers are sized so that the same container may be used for either volume of liquid. For conventional containers, the weight of the container is in the range of 48 to 56 grams and the top load capability of the container is in the range of 45 to 65 lbf. As noted above, top load testing for all containers discussed herein is conducted under ASTM D2659-11.

Referring now to FIGS. 1-4, seen therein is a container 10 embodying the principles of the present invention. The container 10 includes a hollow body 12, generally located between lines A and B, that is closed on its lower end by a base 14. At the opposing end of the body 12, the upper end, a tapered transition section or shoulder 16 extends to a spout 18. The spout 18 may be threaded allowing it to receive a correspondingly threaded closure or cap (not shown).

As seen in FIGS. 4 and 5, the body 12 of the container 10, when viewed from the top or bottom or from a transverse plane, has an elongated, generally rectangular shape. The cross-sectional shape of the body 12 is generally rectangular in that it has two sets of directly opposing and generally parallel sides 20, 22 that are themselves oriented approximately ninety degrees from each other. A first set of the sides 20 of the rectangular cross-sectional shape exhibits a width/dimension (measured across the body 12 of the container 10 in a direction transverse to the longitudinal axis of the container) that is substantially greater than, in some instances at least double, the dimension of the second set of opposing sides 22. Thus, the two sets of opposing sides 20, 22 may be referred to herein as major sides 20 and minor sides 22. Accordingly, the body 12 is generally provided as an elongated rectangle, as opposed to being substantially square. While the major and minor sides 20, 22 are described and/or shown as being parallel with respect to themselves, it will be appreciated that in practice, because of the nature of the plastic material forming the container 10, the sides 20, 22 may not be exactly parallel with themselves and may each exhibit a slightly outwardly (convex) or inwardly (concave) bowed shape.

Unlike conventional rectangular containers, which have rounded corners connecting corresponding major and minor sides, the major and minor sides 20, 22 of the present container 10 are connected by four corners 24 that are not rounded corners. Rather, each corner 24 is comprised of an intermediate side 26 disposed between two sub-corners 28. As will be appreciated from FIGS. 4 and 5, the intermediate sides 26 are generally planar. Accordingly, the body 12 of the container 10, while being generally rectangular, can also be described as having an elongated octagonal shape. The eight sides of the elongated octagonal shape comprising the two major sides 20, the two minor sides 22 and the four intermediate sides 26, and with each adjacent side being connected by one of the eight sub-corners 28, which may be slightly rounded. The cross-sectional shape of the body 12 of the container 10 is therefore sometimes referred to herein as being octo-rectangular. Like the major and minor sides 20, 22, while the intermediate sides 26 are shown and/or referred to as being generally planar, in practice the intermediate sides 26 may exhibit a slightly bowed (convex or concave) shape. Also, while generally shown in FIGS. 4-6 as being parallel to the intermediate wall 26 of the diagonally opposing corner 24, as further discussed below, the opposing intermediate walls 26 need not be parallel to one another.

Optionally formed within each of the intermediate walls 26 is a rib 30. The ribs 30 may extend axially along the intermediate walls 26 from adjacent the base 14, just above line B, past the upper extend of the body 12 at line A and into the transition section 16. Alternatively, the ribs 30 may extend from adjacent the base 14 substantially completely through the transition section and terminate adjacent to the spout 18. In another alternative, the ribs 30 extend from adjacent the base 14 and terminate at a location within the body 12 before the upper extent thereof at line A. In any of the above variations, the ribs may extend completely to the base 14 instead of terminating in the intermediate wall 26 adjacent to the base 14 and above line B. Viewed axially, as seen in FIG. 4, the ribs 30 are centrally located within the intermediate walls 28 and are formed as concave recesses within the intermediate walls 28. As such, the ribs 30 may be referred to as outwardly concave ribs 30. The terminal ends of the ribs 30 may take a variety shapes, including a tapered end 32 or a rounded end, the latter having a common radius of curvature both axially and transversely and the former having different radii of curvature axially and transversely.

FIG. 5 is a cross-sectional view of the container 10, generally taken along line 5-5 in FIG. 1, illustrating the container 10 without the ribs 30 discussed above. As seen in FIG. 5, the minor walls 22 and the intermediate walls 26 each define a width/dimension, designated as D in FIG. 5. In one preferred embodiment, the width D of the minor walls 22 and the width D of the intermediate walls 26 are identical or substantially the same (within +/−10%).

Optionally, the major sides 20 of the body 12 may be formed with a defined label area 34. As shown the label area 34 is slightly recessed in the major side 20, laterally terminating at the sub-corners 28 and axially terminating at upper and lower shoulders 36, 38 formed in the major side 20, generally adjacent to the transition section 16 and the base 14, respectively.

The transition section 16, when viewed in transverse cross-section, as shown in FIG. 6, also has shape that may be described as an elongated, generally rectangular shape. Like the body 12, the transition section 16 has two sets of direct opposing and parallel sides that are oriented ninety degrees from each other and which may also be referred to as major or long sides 40 and minor or short sides 42, with the major sides 40 having a dimension/width (measured in the transverse direction) that is greater (in some embodiments at least double) than the minor sides 42. Also when viewed in cross section, the major sides 40 are generally parallel with each other and the minor sides 42 are generally parallel with each other. It will be appreciated that, in practice, these sides 40, 42 may not be exactly parallel with themselves when viewed cross-sectionally in the transverse plane and may each exhibit a slightly outwardly or inwardly bowed shape, similarly to that described above in connection with the major and minor sides 20, 22 and the intermediate walls 26 of the body 12. In the axial direction, as seen in FIGS. 1-3, the major and minor sides 40, 42 of the transition section 16 exhibit a curvature and their transverse widths decreasingly taper in the direction proceeding from the body 12 to the spout 18.

Also like the body 12, the transition section 16 does not include the round corners of conventional containers. Instead, the transition section 16 is formed with corners 44 that include an intermediate wall 46 disposed between two sub-corners 48. As seen in FIG. 6, in a given transverse cross-section, the intermediate walls 46 are generally planar and, as such, the transition section 16, while being considered an elongated rectangular shape, also may be described as having an elongated octagonal shape. The eight sides of the transition section's elongated octagonal shape are thus comprised of the two major sides 40, the two minor sides 42 and the four intermediate walls 46, with the adjacent sides and walls being connected by one of the eight sub-corners 48.

Like the major and minor sides 40, 42, while the intermediate walls 46 are shown in the transverse cross-section as being substantially planar and parallel to the intermediate wall 46 of the diagonally opposing corner 44, in practice the intermediate walls 46 may exhibit a slightly bowed shape and/or may not be parallel. Also like the major and minor sides 40, 42 of the transition section 16, in the axial direction the intermediate walls 46 of the transition section 16 are curved surfaces that decrease in width proceeding from the body 12 to the spout 18. This decreasing width is similar seen in the sub-corners 48 of the transition section. The decreasing width of the various portions of the transition section 16 are best understood by collectively considering FIGS. 1-4.

In a given transverse cross-section, such as seen in FIG. 6, the minor walls 42 and intermediate walls 46 each define a dimension/width, designated as d₁ and d₂, respectively. As will be appreciated from FIG. 6, the dimension/width d₁ of the minor walls 42 and the dimension/width d₂ of the intermediate walls 46 change as the given transverse cross-sections proceeds from body 12 to the spout 18. In each cross-section, however, the widths d₁ and d₂ are not substantially the same. In the illustrated embodiment width d₁ is smaller than the width d₂.

As noted above, the optional ribs 30 may extend from the intermediate walls 26 of the body 12 into the transition section 16, or more specifically, into the intermediate walls 46 of the transition section 16.

In forming the container 10, heated thermoplastic resin, which may be HDPE as noted above, is forced into an extrusion mechanism that operates as part of a blow molding machine. The extrusion mechanism includes a circular mandrel positioned in a circular die defining a predetermined die gap between the mandrel and the die a predetermined die angle. The resin is caused to flow about the mandrel through the die gap where it exits the extrusion mechanism and forms an extruded parison, which is in the form of a semi-molten, generally circular or oval hollow tube extending from the extrusion mechanism. By controlling the shape of the die angle and the size of the die gap with respect to the mandrel, the shape and proportions of the parison can be controlled.

With the parison in its tube-shaped form, a mold, having a mold cavity corresponding to the shape of the container 10, is closed about the parison. As the mold is closed, the shape of the parison is caused to change from a circular shape to an elliptical shape. With this change in shape, and in combination with the cross-sectional shape of the body 12 of the present container 10, the parison more closely corresponds with the shape of the container 10 and may be kept closer to the walls of the mold cavity that define the shape of the container 10. The above is representatively shown in FIG. 4 where the elliptical shape of the parison is designated by dashed line 50. It will be appreciated that the surfaces defining the walls of the mold cavity correspond to the periphery of the container 10 shown therein.

Once the mold is closed, air is introduced into the parison, which may be through the mandrel, to inflate the parison into conformity with the shape defined by the mold cavity. Replacing the rounded corners of conventional rectangular containers with the intermediate walls 26 and the sub-corners 28 reduces the amount of stretch required of the parison to form these corner replacements. As a result, a thinner parison of less material may be used while resulting thicker and stronger walls in the corners 24 of the container 10. With the addition of the optional ribs 30, the distance may be further reduced, resulting in thicker intermediate walls 26 combined with structural enhancement that may be provided by the ribs 30. With the parison 50 more closely corresponding to the shape of the container 10, the thickness of the wall forming the body 12 and the transition section 16 is more uniform and, therefore, stronger.

Unexpectedly, the inventors have found that by providing a novel relationship between the intermediate walls 26 and the endwalls 22 of the elongated, generally rectangular body 12, the wall thickness about the body 12 of the container 10, can be made more uniform or balanced. The defined relationship between the endwalls 22 and intermediate walls 26 limits the stretch of the parison 50 in the corners 24 of the container 10, which decreases thinning of the container 10 in that region. This in turn allows for extrusion of a thinner walled parison 50, which when blow molded into the shape of the present container 10, can maintain sufficient thickness in the corners 24 while reducing the wall thickness of the major walls 20. The thinner parison 50 and reduction in wall thickness of the major walls 20 allows the container 10 to be lighter in weight without sacrificing top load capabilities. In short, unneeded resin is removed from the major walls 20 without compromising the thickness of resin in the corners 24 of the container 10.

The defined relationship is illustrated in FIG. 10 and, for simplicity, also in FIG. 8. While the discussion of this defined relationship will be presented in connection with container 110 seen in FIG. 10, it will be appreciated that the relationship is equally applicable to the various other containers of the present invention discussed herein. The relationship between the endwalls 122 and the intermediate walls 126 of the elongated, generally rectangular body 112 is defined as a ratio of distances drawn from one intermediate wall 126 and from an endwall 22 adjacent thereto. This relationship is applied to at least one endwall and at least one adjacent intermediate wall but may be applied to both endwalls and at least one of the adjacent intermediate walls. Further, the distances drawn from the intermediate walls may all be the same, some be the same, or none be the same.

It is well known that on an extrusion blow molded container 110, where the two halves of the mold meet and separate, a seam is formed about the container 110. This seam is generally known as the parting line. Where the mold closes on a parison 50, flash is formed at the parting line. As a result, the parting line is more pronounced in that portion of the container 110. In FIG. 10, the more pronounced portion of the parting line is designated at PL in the base 114 of the container 110. A plane P extended through the parting line PL vertically/longitudinally bisects the container 110 at the midpoints M_P of the widths D of the endwalls 122. This plane P may be referred to as the parting line plane P.

From the midpoint M_P of width D of the intermediate wall 126, a line drawn inward along a normal vector intersects the parting line plane P at intersection point I and defines a first distance, which is herein referred to as the diagonal distance D_D. From the midpoint M_P of width D of the endwall 122, a line drawn inward along a normal vector to the intersection point I defines a second distance, which is herein referred to as the plane distance D_P. In FIG. 10 the distances for D_P from each intermediate wall 126 to its intersection I with the parting line plane P is the same. However, in certain variations of the container, one or more of these distances D_P from an intermediate walls may be different.

By providing elongated rectangular containers where the ratio of D_D:D_P is about 1.0, the present inventors have been able to significantly lightweight the container without compromising top load capabilities of the container. The inventors have found that the D_D:D_P ratio is preferably 1.0+/−10% and more preferably less than 1.1. By way of comparison, conventional elongated rectangular containers with rounded corners exhibit a ratio of about 1.2 (with the measurement Dc (see FIG. 8) corresponding to D_D and being measured normal to the tangent of the midpoint of the deepest portion of the rounded corner).

Table 1A presents D_D and D_P measurements (in inches), as well as D_D and D_P ratios, of variously sized containers A-K manufactured in accordance with the teachings herein.

	TABLE 1A
	Container	DD	DP	DD:DP

	A	0.851	0.856	0.994
	B	1.195	1.189	1.005
	C	3.595	3.627	0.991
	D	4.290	4.323	0.992
	E	2.964	2.977	0.996
	F	2.906	2.733	1.063
	G	2.466	2.486	0.992
	H	1.843	1.779	1.036
	-	1.945	1.949	0.998
	J	2.325	2.347	0.991
	K	2.949	2.959	0.997

Table 1B presents Dc and D_P measurements (in inches), as well as Dc and D_P ratios, of conventional containers L-V with rounded corners. Containers L-V generally correspond with containers A-K, respectively, in terms container volume, container depth and container width.

	TABLE 1B
	Container	DC	DP	DC:DP

	L	0.967	0.872	1.109
	M	1.419	1.151	1.233
	N	4.228	3.394	1.246
	0	4.571	3.76	1.216
	P	3.249	2.649	1.227
	Q	3.415	2.694	1.268
	R	2.898	2.281	1.270
	S	2.396	1.941	1.234
	T	5.581	4.594	1.215
	U	4.016	3.154	1.273

An extrusion blow molding machine was utilized to form containers 10 embodying the principles of the present invention. Presented in Tables 2 and 3 are results of forming and testing containers 10 incorporating the principles of the present invention. A mold was constructed having a cavity identical to the shape and volume described above and having a 38 mm (outer diameter) spout 18. Two sets of sample containers were molded. The two sets employed two different amounts of thermoplastic material, thirty-eight (38) grams and forty (40) grams, in forming the containers 10. The results for the 38-gram containers 10 are presented in Table 2, and the results for the 40-gram containers 10 are presented in Table 3.

As seen in Table 2, the actual average weight for the set of 38-gram containers 10 was 38.1 grams, with an average overflow volume of 35.7 fl. Oz. The 38-gram containers 10 also exhibited an average top load capability of 45.45 lbf. And all passed a 6 ft. drop test. When compared with heavier 48 and 56-gram, 1 Qt/1 L containers of a conventional rectangular construction with four rounded corners, the 38-gram containers 10 embodying the principles of the present invention were approximately 20% to 32% lighter in weight, while still providing top load and drop test capabilities consistent with the conventional container and industry standards (a top load of 45 to 65 lbf).

TABLE 2
New 1 Qt/1 L (38 mm
neck) container	Cavity 1	Cavity 2	Cavity 3	Average

Weight (grams)	38.1	38.0	38.1	38.1
Overflow Vol. (fl. oz.)	35.9	35.9	35.9	35.9
Top Load (lbf.)	47.05	44.26	45.04	45.45
Drop Test (6 ft.)	Pass	Pass	Pass	Pass
20.6% less plastic resin than conventional 48 gram 1 Qt/1 L container
32.0% less plastic resin than conventional 56 gram 1 Qt/1 L container

As seen in Table 3, the average weight for the set of 40-gram containers 10 was 40.1 grams, with an average overflow volume of also 35.7 fl. Oz. The 40-gram containers 10 exhibited an average top load capability of 51.67 lbf. And passed a 6 ft. drop test. When compared with heavier, 48 to 56 gram, 1 Qt/1 L containers of a conventional rectangular construction with four rounded corners, the 40-gram containers 10 embodying the principles of the present invention were approximately 16% to 28% lighter in weight, while still providing top load and drop test capabilities consistent with the conventions container and industry standards (a top load of 45 to 65 lbf).

TABLE 3
New 1 Qt/1 L (38 mm
neck) Container	Cavity 1	Cavity 2	Cavity 3	Average

Weight (grams)	40.2	40.2	40.1	40.1
Overflow Vol. (fl. oz.)	35.7	35.7	35.7	35.7
Top Load (lbf.)	52.84	50.56	51.61	51.67
Drop Test (6 ft.)	Pass	Pass	Pass	Pass
16.5% less plastic resin than conventional 48 gram 1 Qt/1 L container
28.4% less plastic resin than conventional 56 gram 1 Qt/1 L container

As a result of the shape of the container 10 discussed above, a lighter weight container 10, on average about 25% lighter, can be formed with comparable top load capabilities to those of the heavier conventional containers. The present container 10 may thus have a weight less than a conventional container at 48 grams, while still achieving a top load capability of greater than 45 lbf. As seen above, containers 10 having a weight between 40 and 41 grams exhibit a top capability significantly greater than 45 lbf. This is believed to be in part the result of the present design enabling the molding process to provide a more consistent, yet similar minimum, wall thickness about the body 12 of the container. The difference in top load capability may therefore be seen as derived from less variance in the wall thickness of the container 10.

Presented in the graph of FIG. 7 is a wall thickness map of the body of a conventional, existing rectangular 1 Qt/1 L container formed using fifty-five (55) grams of thermoplastic resin and the body of a 1 Qt/1 L container 10 according to the principles of the present invention formed using forty-one (41) grams of thermoplastic resin, the latter using over 25% less resin to form the container 10. Beginning at map position A, the lower line (the dashed line) represents the wall thickness measurements of the conventional container at various locations about the body of the container. The upper line beginning a map position A, the solid line, represents the wall thickness measurements of the container 10 according to the principles of the present invention. Map position measurements were taken in corresponding location on each container and are presented in thousandths of an inch.

Progressing counter clockwise about a central position on the body 12 of the container 10, depicted by the solid line:

• • map position H (0.024 in.) corresponds to a central location (beneath the spout 18) on minor side 22;
  • (while not presented in FIG. 7, but seen in FIG. 8, it is noted that the adjacent intermediate wall 26, located between the minor side 22 at map position H and the next major side 20 at map position J, has a wall thickness of 0.022 in.)
  • map position I (0.019 in.) corresponds to the sub-corner 28 adjacent to the major side 20;
  • map position J (0.032 in.) corresponds to a central location on major side 20 as the container is presented in FIG. 1;
  • map position K (0.025 in.) corresponds to the sub-corner 28 adjacent to the major side 20;
  • (while not presented in FIG. 7, but seen in FIG. 8, it is noted that the adjacent intermediate wall 26, located between the major side 20 at map position J and the next minor side 22 at map position L, has a wall thickness of 0.026 in.)
  • map position L (0.027 in.) corresponds to a central location on minor side 22 opposite of the spout 18;
  • (while not presented in FIG. 7, but seen in FIG. 8, it is noted that the adjacent intermediate wall 26 located between the minor side 22 opposite of the spout 18 at map position L and the opposing major side 20 at map position N, has a wall thickness of 0.027 in.)
  • map position M (0.026 in.) corresponds to the next sub-corner 28 adjacent the opposing major side 20.;
  • map position N (0.035 in.) corresponds to a central location on the opposing major side 20;
  • map position O (0.023 in.) corresponds to the sub-corner 28 that that forms the transition from the opposing major side 20 to the next intermediate wall 26, which is adjacent to minor side 22 exhibiting map position H;
  • (while not presented in FIG. 7, but seen in FIG. 8, it is noted that the remaining intermediate wall 26 located between the opposing major side 20 at map position N and the minor side 22 at map position H has a wall thickness of 0.024 in.); and
  • Map positions A-G and P-W represent similar wall thickness measurements taken in the transition section 16 and base 14, respectively, above and below lines A-A and B-B of FIG. 1.

Corresponding to the above, wall thickness measurements on the conventional 1 Qt/1 L container, depicted by the dashed line in FIG. 7, are:

• • map position H (0.027 in.);
  • map position I (0.022 in.), corresponding to rounded corner between positions H and J;
  • map position J (0.043 in.);
  • map position K (0.026 in.), corresponding to rounded corner between positions J and L;
  • map position L (0.029 in.);
  • map position M (0.024 in.), corresponding to rounded corner between positions L and N;
  • map position N (0.046 in.); and
  • map position O (0.022 in.), corresponding to rounded corner between positions N and H.
  • Map positions A-G and P-W represent similar wall thickness measurements taken in the transition section and base, above and below the body of the conventional container.

FIG. 8 is a schematic comparison of the wall thicknesses of a conventional 1 Qt/1 L container (55 grams) and a 1 Qt/1 L container 10 (41 grams) according to the present invention, taken at a location generally corresponding to line 5-5 in FIG. 1. As demonstrated therein, using the geometry of container 10 maintains and allows for an increase in the wall thickness (0.022 to 0.027 inches; an average of 0.0248 in.) of the intermediate walls 26 of the corners 24, as compared to the wall thickness (0.022 to 0.026 inches; an average of 0.0235 in.) of the rounded corners of a conventional rectangular container. Simultaneously, the thicknesses of the corresponding major and minor sides 20, 22 of the present container 10 can be reduced. The wall thickness increase in the intermediate sides 26 translates into greater top load capabilities for the present container 10. It follows that the weight of the present container 10 can be reduced relative to a similarly sized conventional container while still achieving comparable top load capabilities, as was noted above.

TABLE 4
Corresponding Wall Thickness Comparison (inches)

	Existing 1 Qt/1 L
	(55 gram)		New 1 QT/1 L
	conventional		(41 gram)
	container		container
Map position H	0.027		0.024
Map position I	0.022	Intermediate wall	0.022
Map position J	0.043		0.032
Map position K	0.026	Intermediate wall	0.026
Map position L	0.029		0.027
Map position M	0.024	Intermediate wall	0.027
Map position N	0.046		0.035
Map position O	0.022	Intermediate wall	0.024

As seen from Table 4, at map position H, the 55-gram conventional container has a wall thicknesses of 0.043 in. versus 0.032 in. for the 41-gram container 10 hereof. At map position J, the wall thicknesses are 0.043 in. versus 0.032 in. At map position L, the wall thicknesses are 0.029 in. versus 0.027 in. And at map position N, the wall thicknesses are 0.046 on. versus 0.035 in. In all instances of the major and minor sides 20, 22, the wall thickness in the body of the present container 10 is less than that of the conventional container. In comparing the wall thicknesses in rounded corners (map positions I, K, M, O) of the conventional container with the intermediate walls 26 of the present container 10, it is seen that the average wall thickness is increased in the present container 10. As a result, even while reducing the amount of plastic resin used in forming comparable volume containers (by 25%), the top load capability (58 lbf) of the present container 10 is greater than the top load capability (52 lbf) of the conventional container. (See FIG. 7)

The ratio of the wall thickness of the intermediate walls 26 to the major sides 20 of the present container 12 is a measure of wall thickness uniformity and is seen as varying from 0.63 to 0.77 (1.0 being a uniformly thick wall). When compared to the ratio of the rounded corners and corresponding major sides of a conventional container, which varies from 0.51 to 0.55, it is seen that wall thickness of the present container 10 is significantly more uniform, increasing from an average uniformity of about one-half (53%) to an average uniformity of greater than two-thirds (70%).

The above wall thickness ratios, while presented for a 1 Qt/1 L container 10 having a weight of 41 grams, are similarly true for 1 Qt/1 L containers 10 of lesser and greater weight and volumes.

Referring now to FIG. 9, seen therein is a 2.5 Gal/10 L container 110, embodying the principles of the present invention. The container 110 includes a hollow body 112, generally located between lines A and B, that is closed on its lower end by a base 114. At the opposing end of the body 112, the upper end, a transition 116 extends to a spout 118 and includes a handle 119. The spout 18 may be threaded allowing it to receive a correspondingly threaded closure cap (not shown).

As seen in FIGS. 9 and 10, the body 112 of the container 110, when viewed from a transverse plane, has an elongated, generally rectangular shape. The cross-sectional shape of the body 12 includes opposing major and minor sides 120, 122, wherein the major sides 120 are substantially greater, and in the illustrated embodiment at least double, than the dimension of the minor sides 22, similar to the 1 Qt/1 L container discussed above. While the major and minor sides 120, 122 may be described and/or shown as being parallel with respect to themselves, it will again be appreciated the sides 120, 122 may not be exactly parallel with themselves and may each exhibit a slightly outwardly (convex) or inwardly (concave) bowed shape.

The major and minor sides 120, 122 of the container 110 are connected by four corners 124, which are not rounded corners like conventional 2.5 Gal/10 L containers. Rather, like the container 10 of FIG. 1, each corner 124 is comprised of a generally planar, intermediate side 126 disposed between two sub-corners 128. In practice the intermediate sides 126 may exhibit a slightly bowed (convex or concave) shape. In a preferred embodiment, the width D of the minor walls 122 and the width D of the intermediate walls 126 are identical or substantially the same (within +/−10%).

As seen from the above, the body 112 of the container 110 also exhibits an octo-rectangular shape having eight sides that may be generally planar (the two major sides 120, the two minor sides 122 and the four intermediate sides 126) being connected by one of the eight sub-corners 128, which are slightly rounded. As seen in FIG. 10, the body 112 of the container 110 is symmetrical about the parting line plane P and a plane perpendicular to the parting line plane P along the central axis of the container 110, and the ratio of D_D:D_P is in accordance with the above described parameters and about 1.0.

Presented in FIG. 11 is a wall thickness map of the body of a conventional rectangular 2.5 Gal/10 L container formed using 361 grams of thermoplastic resin and the body of a 2.5 Gal/10 L container 110 according to the principles of the present invention formed using 280 grams of thermoplastic resin, the latter using over 22% less resin to form the container 110. The lower line of the two lines drawn initially from map position A to map position B, the solid line, represents the wall thickness measurements of the conventional container at various locations about the body of the container, and the upper line proceeding from map position A to map position B, the dashed line, represents the wall thickness measurements of the container 110 according to the principles of the present invention. Map position measurements were taken in corresponding location on each container and are presented in thousandths of an inch.

Progressing counter clockwise about a central position on the body 112 of the container 110, the map positions may be defined as follows:

• • map position I (0.039 in.) corresponds to a central location (beneath the spout 118) on minor side 122;
  • map position J (0.033 in.) corresponds to a central location in the adjacent intermediate wall 126;
  • map position K (0.032 in.) corresponds to a central location on major side 120 as the container is presented in FIG. 9;
  • map position L (0.037 in.) corresponds to a central location on the next intermediate wall 126;
  • map position M (0.032 in.) corresponds to a central location on minor side 122 opposite of the spout 118;
  • map position N (0.036 in.) corresponds to a central location of the next adjacent intermediate wall 126;
  • map position O (0.034 in.) corresponds to a central location on the opposing major side 120; and
  • map position P (0.041 in.) corresponds to a central location on the next intermediate wall 126, which is adjacent to minor side 122 exhibiting map position I.

Map positions A-H and Q-X represent similar wall thickness measurements taken in the transition section 116 and base 114, respectively, slightly above and below lines A-A and B-B of FIG. 9.

Corresponding to the above, wall thickness measurements on the conventional 2.5 Gal/10 L container are:

• • map position I (0.055 in.);
  • map position J (0.045 in.);
  • map position K (0.060 in.);
  • map position L (0.049 in.);
  • map position M (0.046 in.);
  • map position N (0.042 in.);
  • map position O (0.058 in.); and
  • map position P (0.047 in.).

Map positions A-H and Q-X represent similar wall thickness measurements taken in the transition section and base, just above and below the body of the conventional container.

TABLE 5
Corresponding Wall Thickness Comparison (inches)

	Conventional
	2.5 Gal/10 L		New 2.5 Gal/10 L
	(361 gram)		(280 gram)
	container		container
Map position I	0.055		0.039
Map position J	0.045	Intermediate wall	0.033
Map position K	0.060		0.032
Map position L	0.049	Intermediate wall	0.037
Map position M	0.046		0.032
Map position N	0.042	Intermediate wall	0.036
Map position O	0.058		0.034
Map position P	0.047	Intermediate wall	0.041

As seen from the above and Table 5, the wall thicknesses of the present 2.5 Gal/10 L container 110 have been reduced in all map positions relative to a conventional 2.5 Gal/10 L container. While the reduction in thickness may have been expected because of the reduction in the thermoplastic resin used to form the container 10 (361 grams to 280 grams, a 23% reduction), unexpected is the resulting increase in top load capability, an increase from 87.7 lbf to 128.7 lbf, an increase of 47%.

The ratio of the wall thickness of the intermediate walls 126 to the major sides 120 of the present container 112, the wall thickness uniformity, and seen as varying from a maximum of 1.28 to a minimum of 0.97 (1.0 being a uniformly thick wall), an average of 1.125 and a variance of only 12.5% from uniform. When compared to the ratio of the rounded corners and corresponding major sides of a conventional container, which varies from 0.70 to 0.84, and average of 0.77 and a variance of 23% from uniform. Accordingly, the wall thickness of the present container 10 is significantly more uniform, by a factor of 1.8, almost double.

In addition to providing for a reduction in the weight of the container 10 without sacrificing top load capabilities, the configuration described herein also reduced the surface area of the container 10 (the surface of the container exclusive of the finish and threads) as compared to a conventional shaped rectangular container. Examples of surface area reductions include the following: 1 Qt/1 L containers 10 according to the disclosed configuration exhibited a 4.9 to 5.0% reduction in surface areas as compared to the surface area of a 1 Qt/1 L conventionally shaped rectangular container, 102.212 to 102.258 sq. in. versus 107.302 sq. in.; 2.5 Gal/10 L containers 10 according to the disclosed configuration exhibited a 3.9 to 4.1% reduction in surface areas as compared to the surface area of a 2.5 Gal/10 L conventionally shaped rectangular container, 446.821 to 447.616 sq. in. versus 465.192 sq. in.; and a 5 gallon/20 L container 10 according to the disclosed configuration exhibited a 4.5% reduction in surface area as compared to the surface area of a 5 Gal/20 L conventionally shaped rectangular container, 788.255 sq. in. versus 823.774 sq. in . . . .

While principally described above in connection with a 1 Qt/1 L container 10 and a 2.5 Gal/10 L container 110, the inventive container is not intended to be limited to a 1 Qt/1 L or 2.5 Gal/10 L containers. It will be readily appreciated that the disclosed containers 10, 110 are scalable and may be manufactured in volumes larger or smaller than those discussed herein, while still achieving the benefits discussed above

Referring now to FIGS. 13-20, seen therein are further embodiments of containers 210 embodying the principles of the present invention. The container 210 includes a hollow body 212 that is closed on its lower end by a base 214. The base 214 is generally delineated from the body by line B-B. At the upper end of the body 212 and generally delineated from the body 212 by line S-S, a transition section or shoulder 216 extends upward to a pair of spouts 218, 220, disposed toward the left and right sides, respectively, of the container 210. As such, the container 210 is a dual spout container 210. The spouts 218, 220 may include threads 222, 224 allowing the spouts to receive correspondingly threaded closures, such as a dispensing nozzle (not shown) and a cap (not shown). The dispensing nozzle may be located on spout 18 (the dispensing spout), while the cap may be located on spout 220 (the venting spout). While illustrated and discussed in connection with a dual spout container, it will be appreciated that teachings of the present the discussion of the present figures are equally applicable to a container having a single spout.

An engagement feature 226 is optionally provided about the spout 218. The illustrated engagement feature 226 is a ring with internal threads 227 and is provided to engage and releasably retain an accessory (not shown) for use with the container 210 and its contents, for example, liquid detergent. As such, the accessory may be a measuring cup (not shown) provided with corresponding threads about its open end to engage the internal threads 227.

Between the spouts 218, 220, the transition section 216 may be provided with handle 28 to aid in the carrying and handling of the container 210 by an end consumer. The handle 228 is preferably hollow to aid in the dispensing of the contents, particularly liquid contents, from the container though the dispensing spout 218.

As seen in FIGS. 16 and 17, the body 212 of the container 210 has a generally rectangular shape. In this regard, the body 212 includes a front sidewall 230 that opposes a rear sidewall 232. The front and rear sidewalls 230, 232 correspond with the previously discussed major sidewalls and may generally mirror each other in width, height and be generally planar with, optionally, a bow or slight in-plane bend about a vertical axis A located approximately midway across the width of the sidewalls 230, 232 (see FIG. 5).

Also referring to FIGS. 16 and 17, the body 212 of the container 210 includes a right endwall 234 that opposes a left endwall 236. The right and left endwalls 234, 236 correspond with the previously discussed minor sidewalls and are also generally planar. The endwalls 234, 236 may also be bowed, that is provided with an in-plane bend about a vertical axis A located about midway across the width of the endwalls 234, 236 (see FIG. 4). This in-plane bend may be less than the in-plane bend defined in the sidewalls 230, 232.

Between adjacent ones of the sidewalls 230, 232 and the endwalls 234, 236 are the corners 238 of the container 210. Each corner 238 is comprised of an intermediate wall 240 disposed between two sub-corners 242. As will be appreciated from FIGS. 16 and 17, the intermediate walls 240 are generally planar and may be slightly bowed, while the sub-corners 242 are rounded.

As shown in FIG. 17, the widths WI₁ of those intermediate walls 240 adjacent to the right endwall 234, designated as 240′, may be identical to, or substantially the same (±10%) as, the width W_R of the right endwall 234. However, the widths W_I2 of the intermediate walls 240 adjacent to the left endwall 236, designated as 240″, are not the same as the width W_L of left endwall 236. In some implementations, the widths W_I2 of the intermediate walls 240″ adjacent to the left endwall 236 may be less than of the width W_L of left endwall 236 and even half the width W_L of the left endwall 236. Additionally, the widths W_I2 of the intermediate walls 240″ adjacent to the left endwall 236 may be less than widths W_I1 of the intermediate walls 240′ adjacent to the right endwall 234 and to the width W_R of the right endwall 234.

While the endwalls 234, 236 generally oppose one another, with the above dimensioning of the intermediate walls 240′, 240″, the container 210 is provided with the left endwall 236 exhibiting a width W_L that is greater than the width W_R of the right endwall 234. In this regard, the body of the container is asymmetrical from end-to-end and about the plane that is perpendicular to the parting line plane P and extending along the central axis. The greater width W_L of the left endwall 236 allows the container 210 to be set or laid on the endwall 236, instead of the base 214, in a stable manner that further allows for the contents of the container 210 to be dispensed through the dispensing spout 218 and a dispensing nozzle. In this position, the left endwall 36 operates as a secondary base, and the container 210 does not need to tilt to be dispensed the contents from the container 210. Even with its end-to-end asymmetrical nature, the container 210 continues to provide lighter weight and enhanced top load capabilities, as discussed above, when compared to a conventional container of similar size.

Shown in FIG. 18 is an outline (at a midpoint, height-wise, in the body 212) of the perimeter A1 of the container 210 seen in FIGS. 13-17, an outline of the perimeter A2 of a variant of the container 210 seen in FIGS. 13-17, and the outline of the perimeter S of a container that is symmetrical relative to its right and left endwalls, similar to the containers depicted in FIGS. 1-5, 9 and 10. As will be appreciated, the outlines of the perimeters A1, A2, and S also correspond to the perimeter of a mold cavity defining the shape of the respective containers.

The defined relationship discussed above between an endwall and an adjacent intermediate wall of the elongated, generally rectangular body equally applied to the respective endwalls 234, 236 and intermediate walls 240, 242 the container 210 seen in FIGS. 13-17 and its variant seen in FIG. 18.

As shown in FIG. 17, the ratio of D_D:D_P is in accordance with the above described parameters. On the right side of the container 210 the width of the endwall 234 is substantially the same as the width of the adjacent intermediate walls 240′. From the midpoint M_D of width W_I1 of the intermediate wall 240′, a line drawn inward along a normal vector intersects the parting line plane P at intersection point I and defines the diagonal distance D_D. From the midpoint M_P of width W_R of the endwall 234, a line drawn inward along a normal vector to the intersection point I defines the plane distance D_P. This ratio of D_D:D_P is about 1.0, preferably 1.0+/−10% and more preferably less than 1.1.

On the left side of the container 210 the width of the endwall 236 is not the same as the widths of the adjacent intermediate walls 240″. From the midpoint M_P of width W_I2 of the intermediate wall 240″, a line drawn inward along a normal vector intersects the parting line plane P at intersection point I and defines the diagonal distance D_D. From the midpoint M_D of width W_L of the endwall 236, a line drawn inward along a normal vector to the intersection point I defines the plane distance D_P. This ratio of D_D:D_P is also about 1.0, preferably 1.0+/−10% and more preferably less than 1.1.

As is apparent from FIG. 17, the widths may be different between an intermediate wall and an adjacent endwall while still maintaining the desired ratio of D_D:D_P. What is not quite apparent in FIG. 17, but is made readily apparent in FIG. 18, is that angle of the intermediate walls relative to the adjacent end wall may be different while still maintaining the desired ratio of D_D:D_P.

Generally illustrated in FIG. 19 is further variation of the container 210. The variation of body 212 of the container 210 is depicted via a perimeter line P overlaid on a symmetrical container S. As with the other containers disclosed herein, the desired ratio of D_D:D_P is maintained.

As represented in the FIG. 19, for the variant container defined by perimeter P, the widths W_I3 of the intermediate walls 240.1, 240.2 adjacent to the right endwall 234 are the identical to, or substantially the same (±10%) as, the width W_R of the right endwall 234. Similarly, the widths of the intermediate walls 240.3, 240.4 adjacent to the left endwall 236, while not depicted, are identical to, or substantially the same (±10%) as, the width of left endwall 236.

However, the acute angle α provided between the planes defined by the left and right endwalls 234, 236 and the planes defined by intermediate walls 240.1, 240.3 adjacent to the front sidewall 230 is different than the acute angle β provided between the planes defined by the right and left endwalls 234, 236 and the planes defined by intermediate walls 240.2, 240.4 adjacent to the rear sidewall 232. Accordingly, the body 212 of the container 210 is asymmetrical front-to-back (the front half of the body 212 is asymmetrical to the rear half of the body 212) about the parting line plane P but is symmetrical from end-to-end or right to left in the figure (the right half of the body 212 is symmetrical to the left half of the body 212) about the plane along the central axis and perpendicular to the parting line plane P. Resultantly, the front sidewall 230 has a width greater than the rear sidewall 232 and provides an increased label area thereon.

A further variation of the container 210 is depicted in FIG. 20. Similar to FIG. 19, the body 212 of the container 210 is generally represented via a perimeter line P overlaid on a symmetrical container S.

As represented in the FIG. 20, the widths W_I3 of the intermediate walls 240.5, 240.6 adjacent to the right endwall 234 are the identical to, or substantially the same (±10%) as, the width W_R of the right endwall 234. However, the acute angle α provided between the plane defined by the right endwall 234 and the plane defined by intermediate wall 240.5 adjacent to the front sidewall 230 is different than the acute angle β provided between the plane defined by the right endwall 234 and the plane defined by intermediate wall 240.6 adjacent to the rear sidewall 232. Thus, the right end of the body 212 in FIG. 20 is asymmetrical front-to-rear, similarly to the container 210 of FIG. 19.

Regarding the left side of the body 212 of the container 210 represented in FIG. 20, the width W_L of the left endwall 236 is greater than the width W_R of the right endwall 234. As previously discussed, this greater width allows the container 210 to not only stand on its base but also allows the container 210 to more stably rest on the left endwall 236.

Further, the acute angle α provided between the plane defined by the left endwall 236 and the plane defined by intermediate wall 240.7, located between the left endwall 236 and the front sidewall 230, is different than the acute angle β provided between the plane defined by the left endwall 236 and the plane defined by intermediate wall 240.8, located between the left endwall 236 and the rear sidewall 232. Accordingly, the left half of the body 212 is also asymmetrical front-to-rear. However, the width W_I4 of the intermediate endwall 240.7 is less than the width W_I5 of the intermediate endwall 240.8. As such, the body 212 is asymmetrical both end-to-end (right half to left half of the body 212) and front-to-rear (front half to rear half of the body 212). This is achieved while providing the front sidewall 230 with a width greater and increased label area than the rear sidewall 232.

Notwithstanding the asymmetries seen in FIGS. 19 and 20, with the relationship discussed above between an endwall and an adjacent intermediate wall of the elongated generally rectangular body, the ratio of D_D):D_P, is applied to the respective endwalls 234, 236 and adjacent intermediate walls 240.1-240.8 and a more uniform wall thickness is obtained in the containers 210 and less resin is utilized without compromising top load strength. As shown in FIG. 19, on the right side of the container 210, From the midpoint M_D of width of the intermediate wall 240.3, a line drawn inward along a normal vector intersects the parting line plane P at intersection point I and defines the diagonal distance D_D. From the midpoint M_P of width W_R of the endwall 234, a line drawn inward along a normal vector to the intersection point I defines the plane distance D_P. The ratio of D_D:D_P is about 1.0, preferably 1.0+/−10% and more preferably less than 1.1.

As seen from the above, ratio of D_D:D_P being about 1.0 can be applied between an endwall and an adjacent intermediate wall of the elongated generally rectangular body to achieve reduced weight while maintaining strength in the container. It is noted that the corner construction disclosed herein can be applied to less than all four corners of a container having an elongated generally rectangular body. Applying the construction to less than all corners of the container, while not obtaining all of the lightweighting benefits, the container would obtain the increased strength benefits of a more uniform wall thickness.

As a result of the configurations discussed above, a lighter weight container can be formed with comparable or improved top load capabilities to those conventional containers having rounded corners. The above can be achieved regardless of whether the container is symmetrical, or asymmetrical and providing larger labeling opportunities or the ability of the container to be stable when laid on its endwall for the dispensing of the contents.

The above description is meant to be illustrative of at least one preferred implementation incorporating the principles of the invention. One skilled in the art will really appreciate that the invention is susceptible to modification, variation, and change without departing from the true spirit and fair scope of the invention, as defined in the claims that follow. The terminology used herein is therefore intended to be understood in the nature of words of description and not words of limitation.