DESSAINT ALAIN (BE)
MATTHIEU NATALIA (BE)
| WO2000059790A1 | 2000-10-12 | |||
| WO2006113428A2 | 2006-10-26 | |||
| WO2013099573A1 | 2013-07-04 | |||
| WO2000059790A1 | 2000-10-12 | |||
| WO2006113428A2 | 2006-10-26 |
| EP2103413A1 | 2009-09-23 | |||
| US20130207317A1 | 2013-08-15 | |||
| US20120267381A1 | 2012-10-25 | |||
| EP2103413A1 | 2009-09-23 |
| CLAIMS A process for making a-stretched-blow molded container having at least one deep concave grip (G), said process comprising the steps of: a) providing a preform in a mould cavity (MC), b) stretch-blow moulding the preform to form an intermediate stretched blow-molded container (1 ) comprising a biaxially stretched-blow molded hollow body (10) having a first vertical central plane (P1 ) and a second vertical central plane (P2) perpendicular to the first vertical central plane (P1 ), said stretched-blow molded hollow body (10) comprising a container side wall (10a), at least one convex and outwardly protruding deformable region (102) that is formed in the container side wall (10a), c) pushing inwardly said at least one convex and outwardly protruding deformable region (102) of the intermediate container (1 ) towards the first vertical central plane (P1 ), in such a way to invert said at least one convex and outwardly protruding deformable region (102) and form in a final container (1 ') at least one deep concave grip (G) comprising an undercut region (U) that cannot be reached from the outside of the container by a rectilinear axle that is moved in a direction perpendicular to said first central plane (P1 ). The process of claim 1 , wherein the outwardly protruding deformable region (102) that is formed in the container side wall (10a) in step b) protrudes outwardly in such a way that the orthogonal projection of the outwardly protruding deformable region (102) on the first central plane (P1 ) is located within the container. The process of any one of the previous claims, wherein the undercut region (U) of the deep concave grip (G) is located on one side of the second vertical central plane (P2) and at least a part of the deep concave grip (G) is located on the other side of the a second vertical central plane (P2). The process of any one of the previous claims, wherein the at least one convex and outwardly protruding deformable region (102) is off-center from the second vertical central plane (P2). 5. The process of claim 4 wherein all the at least one convex and outwardly protruding deformable region (102) is off-center from the second central plane (P2). 6. The process of any one of the previous claims, wherein the maximum gripping dimension (DR) of the stretched-blow molded hollow body (10) measured next to and on one side of the convex and outwardly protruding deformable region (102) in a gripping region of the container, in a cross section plane that is perpendicular to the said first (P1 ) and second (P2) central vertical planes and that is intersecting the recess (101 ), and in a direction perpendicular to the first vertical plane (P1 ), is smaller than the maximum dimension (DL) of the stretched- blow molded hollow body (10) measured next to and on the other side of the convex and outwardly protruding deformable region (102) in the same cross section plane and direction. 7. The process of any one of the previous claims, wherein in the stretch- blow moulding step b), at least one recess (101 ) off-center from the second vertical central plane (P2) is formed in said container side wall (10a), wherein the said recess (101 ) comprises a first (1010) and a second opposite (101 1 ) lateral walls and a bottom portion (1022) joining said first lateral wall (1010) to said second lateral wall (101 1 ), wherein said convex and outwardly protruding deformable region (102) comprises an outwardly protruding invertable lateral wall (1020), that is an extension of said second lateral wall (101 1 ) of the recess (101 ) at least on a portion of the periphery of the convex and outwardly protruding deformable region (102), and that extends beyond the first lateral wall (1010) of the recess (101 ), and a front wall (1021 ) that is an extension of this outwardly protruding invertable lateral wall (1020), wherein at least the junction (H) between the bottom portion (1012) and the second lateral wall (101 1 ) of said recess (101 ) forms an hinge on the periphery of the outwardly protruding convex deformable region (102) for inverting the said outwardly protruding convex deformable region ((102) and the second lateral wall (101 1 ) of the recess (101 ) by pushing them inwardly in order to form said concave deep grip (G). 8. The process of claim 7, wherein the recess (101 ) defines a closed contour and the convex and outwardly protruding deformable region (102) is surrounded by said recess (101 ). 9. The process of any one of claims 7 or 8, wherein the depth of the recess (101 ) is not the same on the whole periphery of the recess. 10. The process of any one of claims 6 to 8, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the depth (DP1 ) of said recess measured in said first portion (101 a) of the recess is smaller than the depth (DP2) of said recess measured in said second portion (101 b) of the recess. 1 1 . The process of any one of claims 7 to 10, wherein the maximum depth of said recess (101 ) is not more than 10mm, and preferably not more than 5mm. 12. The process of any one of claims 7 to 1 1 , wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the depth (DP1 ) of said recess in said first portion (101 a) is not more than 5mm. 13. The process of any one of claims 7 to 12, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the depth (DP1 ) of said recess in said first portion (101 a) is between about l imm and about 2mnn. 14. The process of any one of claims 7 to 13, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is intersected by the second vertical central plane (P2). 15. The process of any one of claims 7 to 14, wherein all the recess (101 ) is off-center from the second central plane (P2). 16. The process of claim 15, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2), and wherein the depth (DP2) of said recess in said second portion (101 b) is not more than 10mm. 17. The process of any one of claims 7 to 16, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the distance (d1 ) between the bottom of the first portion (101 a) of the recess ( 101 ) and the first central plane (P1 ) is smaller than or equal to the distance (d2) between the bottom of said second portion (101 b) of the recess (101 ) and the first central plane (P1 ). 18. The process of any one of claims 7 to 17, wherein the symmetry plane (P3), that is substantially tangential to the hinge (H) at the junction between the bottom portion (1012) and the second lateral wall (101 1 ) of said recess (101 ) defines with the first central plane (P1 ) an angle β of not more than 15°. 19. The process of any one of claims 7 to 18, wherein the lateral invertable wall (1020) of the convex and outwardly protruding deformable region (102) defines with the second central plane (P2) an angle a of at least 10°. 20. The process of any one of claims 7 to 19, wherein the shape of said recess (101 ) is elongated. 21 . The process of any one of claims 7 to 20, wherein the bottom portion (1012) of the recess (101 ) is a flat wall . 22. The process of any one of claims 7 to 20, wherein the bottom portion (1012) of the recess (101 ) is a concave arc-shaped wall of small curvature radius. 23. The process of any one of claims 7 to 22, wherein in the stretch-blow moulding step b), two opposite convex and outwardly protruding deformable regions (102) are formed. 24. The process of claim 23, wherein each opposite convex and outwardly protruding deformable regions (102) is surrounded by a recess (101 ). 25. The process of any one of claim 23 or 24, wherein the two opposite convex and outwardly protruding deformable regions (102) are identical and the two opposite recesses (101 ) are identical. 26. The process of any one of claims 7 to 25, wherein said first (1010) and a second opposite (101 1 ) lateral walls of said recess (101 ) are flat or smoothly curved without any hinge region. 27. The process of any one of the previous claims, wherein the maximum gripping dimension (DR) is between about 30mm and about 70mm, and preferably between about 40mm and about 60mm. 28. The process of any one of the previous claims, wherein in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the final container (1 '), the minimum depth (DP) of each concave grip (G) measured in a direction perpendicular to the first central plane (P1 ), is more than 50%, and preferably more than 70% of half the said maximum gripping dimension (DR) of the stretched- blow molded hollow body (10). 29. The process of any one of the previous claims, wherein in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the final container (1 '), the minimum depth (DP) of each concave grip (G) measured in a direction perpendicular to the first central plane (P1 ), is at least 15mm, and preferably at least 20mm. 30. The process of any one of the previous claims, in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the final container (1 '), the minimum distance (D2) between the bottom wall (1021 ') of each deep concave grip (G) and the first central plane (P1 ) is preferably not more than 5mm, and more preferably not more than 2mm. 31 . An intermediate stretched-blow molded container (1 ) comprising a biaxially stretched-blow molded hollow body (10) having a first vertical central plane (P1 ) and a second vertical central plane (P2) perpendicular to the first vertical central plane (P1 ), wherein said stretched-blow molded hollow body (10) comprises a container side wall (10a), at least one recess (101 ) that is formed in said container side wall (10a), that is off-center from the second vertical central plane (P2), and at least one convex and outwardly protruding deformable region (102) that is formed in the container side wall (10a), wherein the maximum gripping dimension (DR) of the stretched-blow molded hollow body (10) measured next to and on one side of the convex and outwardly protruding deformable region (102) in a gripping region of the container, in a cross section plane that is perpendicular to the said first (P1 ) and second (P2) central vertical planes and that is intersecting the recess (101 ), and in a direction perpendicular to the first vertical plane (P1 ), is smaller than the maximum dimension (DL) of the stretched-blow molded hollow body (10) measured next to and on the other side of the convex and outwardly protruding deformable region (102) in the same cross section plane and direction, wherein the said recess (101 ) comprises a first (1010) and a second opposite (101 1 ) lateral walls and a bottom portion (1022) joining said first lateral wall (1010) to said second lateral wall (101 1 ), wherein said convex and outwardly protruding deformable region (102) comprises an outwardly protruding invertable lateral wall (1020), that is an extension of said second lateral wall (101 1 ) of the recess (101 ) at least on a portion of the periphery of the convex and outwardly protruding deformable region (102), and that extends beyond the first lateral wall (1010) of the recess (101 ), and a front wall (1021 ) that is an extension of this outwardly protruding invertable lateral wall (1020), wherein at least the junction (H) between the bottom portion (1012) and the second lateral wall (101 1 ) of said recess (101 ) forms an hinge on the whole periphery of the outwardly protruding convex deformable region (102) for inverting the said outwardly protruding convex deformable region ((102) and the second lateral wall (101 1 ) of the recess (101 ) by pushing them inwardly in order to form a concave grip (G). 32. The intermediate stretched-blow molded container (1 ) of claim 31 , wherein the recess (101 ) defines a closed contour and the convex and outwardly protruding deformable region (102) is surrounded by said recess (101 ). 33. The intermediate stretched-blow molded container (1 ) of any one of claims 31 or 32, wherein the depth of the recess (101 ) is not the same on the whole periphery of the recess. 34. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 33, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the depth (DP1 ) of said recess measured in said first portion (101 a) of the recess is smaller than the depth (DP2) of said recess measured in said second portion (101 b) of the recess. 35. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 34, wherein the maximum depth of said recess (101 ) is not more than 10mm, and preferably not more than 5mm. 36. The intermediate stretched-blow molded container (1 ) ) of any one of claims 31 to 35, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the depth (DP1 ) of said recess in said first portion (101 a) is not more than 5mm. 37. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 36, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the depth (DP1 ) of said recess in said first portion (101 a) is between about 1 mm and about 2mm. 38. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 37, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is intersected by the second vertical central plane (P2). 39. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 37, wherein all the recess (101 ) is off-center from the second central plane (P2). 40. The intermediate stretched-blow molded container (1 ) of claim 39, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2), and wherein the depth (DP2) of said recess in said second portion (101 b) is not more than 10mm. 41 . The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 40, wherein said off-center recess (101 ) comprises a first portion (101 a) that is far away from the second vertical central plane (P2) and a second portion (101 b) that is closest to the second vertical central plane (P2) or is intersected by the second vertical central plane (P2), and wherein the distance (d1 ) between the bottom of the first portion (101 a) of the recess ( 101 ) and the first central plane (P1 ) is smaller than or equal to the distance (d2) between the bottom of said second portion (101 b) of the recess (101 ) and the first central plane (P1 ). 42. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 41 , wherein the symmetry plane (P3), that is substantially tangential to the hinge (H) at the junction between the bottom portion (1012) and the second lateral wall (101 1 ) of said recess (101 ) defines with the first central plane (P1 ) an angle β of not more than 15°. 43. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 42, wherein the lateral invertable wall (1020) of the convex and outwardly protruding deformable region (102) defines with the second central plane (P2) an angle a of at least 10°. 44. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 43, wherein the shape of said recess (101 ) is elongated. 45. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 44, wherein the bottom portion (1012) of the recess (101 ) is a flat wall. 46. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 42, wherein the bottom portion (1012) of the recess (101 ) is a concave arc-shaped wall of small curvature radius. 47. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 46, comprising two opposite convex and outwardly protruding deformable regions (102). 48. The intermediate stretched-blow molded container (1 ) of claim 47, wherein each opposite convex and outwardly protruding deformable regions (102) is surrounded by a recess (101 ). 49. The intermediate stretched-blow molded container (1 ) of any one of claim 47 or 48, wherein the two opposite convex and outwardly protruding deformable regions (102) are identical and the two opposite recesses (101 ) are identical. 50. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 49, wherein the maximum gripping dimension (DR) is between about 30mm and about 70mm, and preferably between about 40mm and about 60mm. 51 . The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 50, wherein each convex and outwardly protruding deformable regions (102) protrudes outwardly in such a way that the orthogonal projection of the outwardly protruding deformable region (102) on the first central plane (P1 ) is located within the container. 52. The intermediate stretched-blow molded container (1 ) of any one of claims 31 to 51 wherein said first (1010) and a second opposite (101 1 ) lateral walls of said recess (101 ) are flat or smoothly curved without any hinge region. 53. A process for making a-stretched-blow molded container comprising the steps of : d) providing a preform in a mould cavity (MC), e) stretch-blow moulding the preform to form an intermediate stretched blow-molded container (1 ) defined in any one of the claims 31 to 52, f) pushing inwardly each convex and outwardly protruding deformable region (102) of the intermediate container (1 ) towards the first vertical central plane (P1 ), in such a way to invert each convex and outwardly protruding deformable region (102) and the second lateral wall (101 1 ) of each recess (101 ) and form at least one grip (G) in a final container (1 '). 54. The process of claim 53, wherein the intermediate stretched blow- molded container (1 ) is designed in such a way that after step c), in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the final container (1 '), the minimum depth (DP) of each concave grip (G) measured in a direction perpendicular to the first central plane (P1 ), is more than 50%, and preferably more than 70% of half the said maximum gripping dimension (DR) of the stretched-blow molded hollow body (10). 55. The process of claim 53 or 54, wherein the intermediate stretched blow-molded container (1 ) is designed in such a way that after step c), in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the final container (1 '), the minimum depth (DP) of each concave grip (G) measured in a direction perpendicular to the first central plane (P1 ), is at least 15mm, and preferably at least 20mm. 56. The process of any one of claims 53 to 55, wherein the intermediate stretched blow-molded container (1 ) is designed in such a way that after step c), in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the final container (1 '), the minimum distance (D2) between the bottom wall (1021 ') of each deep concave grip (G) and the first central plane (P1 ) is preferably not more than 5mm, and more preferably not more than 2mm. 57. The process of any one of claims 53 to 56, wherein the intermediate stretched blow-molded container (1 ) is designed in such a way that after step c), at least one deep concave grip (G) comprises an undercut region (U) that cannot be reached from the outside of the container by a rectilinear axle that is moved in a direction perpendicular to said first central plane (P1 ). 58. The process of claim 57, wherein the undercut region (U) of the deep concave grip (G) is located on one side of the second vertical central plane (P2) and at least a part of the deep concave grip (G) is located on the other side of the a second vertical central plane (P2). 59. The process of any one of claims 53 to 58, wherein said first (1010) and a second opposite (101 1 ) lateral walls of said recess (101 ) are flat or smoothly curved without any hinge region. 60. A stretched-blow molded container (1 ') issued from the process of any of claims 53 to 59 and comprising at least one deep concave grip (G) in the container sidewall (10a). 61 . The stretched-blow molded container (1 ') of claim 60, wherein in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the container, the minimum depth (DP) of each concave grip (G) measured in a direction perpendicular to the first central plane (P1 ), is more than 50%, and preferably more than 70% of half the said maximum gripping dimension (DR) of the stretched-blow molded hollow body (10). 62. The stretched-blow molded container (1 ') of claim 60 or 61 , wherein in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the container, the minimum depth (DP) of each concave grip (G) measured in a direction perpendicular to the first central plane (P1 ), is at least 15mm, and preferably at least 20mm. 63. The stretched-blow molded container (1 ') of any one of claims 60 to 62, wherein in at least one horizontal cross section perpendicular to the first (P1 ) and second (P2) vertical planes of the container, the minimum distance (D2) between the bottom wall (1021 ') of each deep concave grip (G) and the first central plane (P1 ) is preferably not more than 5mm, and more preferably not more than 2mm. 64. The stretched-blow molded container (1 ') of any one claims 60 to 63 wherein at least one deep concave grip (G) comprises an undercut region (U) that cannot be reached from the outside of the container by a rectilinear axle that is moved in a direction perpendicular to said first central plane (P1 ). 65. The stretched-blow molded container (1 ') of claim 64, wherein each convex and outwardly protruding deformable regions (102) protrudes outwardly in such a way that the orthogonal projection of the outwardly protruding deformable region (102) on the first central plane (P1 ) is located within the container. |
CONTAINER Technical field
The present invention relates to the field of stretched-blow molded containers having an integrally molded deep grip, preferably with good ergonomics for large containers.
Prior art
Processes for making stretched-blow molded containers, and in particular injection stretched-blow molded (ISBM) containers, having an integrally molded deep handgrip have already been disclosed in PCT applications WO 00/59790 and WO 2006/1 13428, and in European patent application EP 2 103 413.
According to said known processes, in a first blow molding step a first intermediate stretched-blow molded container is formed by stretch-blow molding a preform in a blow mold cavity to form an intermediate container comprising opposite "ears" or "bubbles" forming convex deformable regions. Then in a second boxing step carried out either in the same blow mold cavity or in a specific boxing mould, each deformable region of the intermediate container is mechanically pushed inwardly, preferably while maintaining a certain pressure inside the container, to invert the deformable region and form a molded hand grip in a final container.
The boxing step can be carried out when the temperature of the first intermediate stretched-blow molded container is below ("cold boxing") the glass transition temperature (Tg) of the polymer constituting the container, or when the temperature of the first intermediate stretched-blow molded container is above ("hot boxing") said glass transition temperature (Tg) as disclosed in EP 2 103 413.
The deformable convex regions of the intermediate container described In PCT application WO 00/59790 and shown on the drawings thereof are formed in two flat and opposite parallel vertical walls of the intermediate container, which limits the container size and volume for an ergonomic gripping.
In PCT application WO 2006/1 13428, the container side wall is designed in order to advantageously form a hand gripping region of smaller dimensions, and the deformable convex regions are formed in curved portions of the container side wall, which advantageously enables to make a container of large volume that is easier to grip. But the depth of the concave regions forming the molded hand grip after inward deformation of the deformable convex regions of the intermediate container is limited, and the solution disclosed in said PCT application WO 2006/1 13428 does not enable to make ISBM containers of large volume having a molded hand grip that is sufficiently deep for an ergonomic gripping of the container.
In European patent application EP 2 103 413, the outward "bubbles" forming the deformable convex regions can be inverted only by carrying out a hot boxing step, i.e. when the temperature of the first intermediate stretched- blow molded container is above the glass transition temperature (Tg) of the polymer constituting the container, and are not suitable for carrying out a cold boxing step.
Objective of the invention
An objective of the invention is to propose a novel solution for making a stretched-blow molded containers having an integrally molded deep grip, said solution overcoming the drawbacks of the aforesaid solutions of the prior art.
Summary of the invention
A first object of the invention is a process, as defined in claim 1 ,for making a stretched-blow molded container with at least one concave deep grip with an undercut region.
A second object of the invention is an intermediate stretched-blow molded container as defined in claim 31 .
A second object of the invention is a process, as defined in claim 53, for making a-stretched-blow molded container with least one concave grip. A third object of the invention is an ISBM container with least one concave grip as defined in claim 60.
Brief description of the drawings
Other technical characteristics and advantages of the invention will appear more clearly on reading the following detailed description which is made by way of non-exhaustive and non-limiting example, and with reference to the appended drawings, as follows:
- Figure 1 is a side view of an example of an intermediate stretched blow-molded container of the invention.
- Figure 2 is schematic side side view of a blow mold cavity containing the intermediate stretched blow-molded container of figure 1 .
- Figure 3 is a view in cross section of Figure 2 in plane Ill-Ill.
- Figure 4 is a side view of an example of the final stretched blow- molded container obtained from the intermediate stretched blow- molded container of figure 1 .
- Figure 5 to 15 are views in cross section of the final stretched blow- molded container of figure 4 respectively in horizontal cross section planes V-V, VI-VI, VII-VII, VIM-VIM, IX-IX, X-X, XI-XI, XII-XII, XIM-XIM, XIV-XIV, XV-XV, said views showing in dotted lines the convex and outwardly protruding deformable region of the intermediate stretched blow-molded container of figure 1 .
- Figure 16 is a view in cross section of the final stretched blow-molded container of figure 4 in cross section plane XVI-XVI.
- Figure 17 is an enhanced detail of figure 10.
- Figure 18 is another example of profile for the bottom portion of the recess of an intermediate stretched blow-molded container of the invention.
- Figures 19 to 25 are other examples of horizontal cross section of a final stretched blow-molded container of the invention, the convex and outwardly protruding deformable region of the corresponding intermediate stretched blow-molded container being represented in dotted lines.
Detailed description
Some preferred embodiments of the invention are discussed in detail below. While specific exemplary embodiments are discussed, it should be understood that this is done for illustration purpose only. A person skilled in the art will recognize that other container designs or container dimensions can be used without parting from the spirit and scope of the invention.
Referring now to the drawings, figure 1 illustrates an intermediate plastic container 1 having a biaxially stretched blow-molded hollow body 10, and a cylindrical neck finish 1 1 comprising a top pouring opening 1 1 a. The biaxially stretched blow-molded hollow body 10 comprises a vertical side wall 10a extended by a bottom wall 10b forming the base of the container.
Within the scope of the invention, the intermediate plastic container 1 can be made of any thermoplastic material that can be processed by using injection stretched bow molded techniques. Preferred thermoplastic materials useful for the invention are polyesters, and in particular polyethylene terephtalate (PET), homo or copolymers thereof, and blend thereof. Other materials suitable for use in the present invention are polypropylene (PP), polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC) and polylactic acid (PLA), homo or copolymers thereof, and blend thereof.
Although the containers shown in the appended drawings are monolayer containers, the invention is however not limited to monolayer containers but encompasses also multilayer containers.
A well-known injection stretched blow molding technique can be used for making the intermediate plastic container 1 . In particular, a small tubular plastic preform having the same neck finish 1 1 than the intermediate container 1 is knowingly injected in a mould. In reference to figures 2 and 3, this preform is subsequently biaxially stretched in a mold cavity MC of a blow mold 2 in order to form the intermediate container 1 . During this blow molding step, the neck finish 1 1 is not stretched and only the body of the preform below the neck finish 1 1 is biaxially stretched in the mold cavity MC, in order to form the stretched blow-molded hollow body 10 of the container 1 .
Within the scope of the invention a "one stage process" or a "two stages process" can be carried out. In the one stage process", the stretch- blow molding step of the preform is performed in line immediately after the first injection step (preform injection). In the "two stages process", the stretch-blow molding step of the preform in the blow mold cavity is postponed, and a reheating of the preform is performed prior to this stretch- blow molding step.
The blow mold 2 knowingly comprises two halves 2a, 2b that define a contact plane P when the mold is closed as depicted on figure 3. These two mold halves 2a ,2b can be moved away from each other in a direction perpendicular to plane P (arrows F of figure 3) in order to open the mold cavity MC and remove the container from the mold cavity MC.
The outer surface of the stretched blow-molded hollow body 10 of the intermediate container 1 comprises two visible and thin molding lines PL (figure 1 ), commonly referred as "parting lines". These parting lines PL are formed at each vertical intersection line L (figure 3) between the two mold halves 2a, 2b and the stretched blow molded hollow body 10. On figure 1 , only one parting line PL is visible, the other opposite parting line PL being hidden and located on the opposite face of the container 1 . These parting lines PL define for the intermediate container 1 a first main central vertical plane P1 that includes these parting lines PL. This first main central vertical plane P1 corresponds to aforesaid contact plane P when the container 1 is in the closed mold cavity (figure 3).
As depicted on the appended figures, the intermediate container 1 also comprises a second vertical central plane P2 perpendicular to the first vertical central plane P1 . The vertical axis C at the intersection between the first P1 and second P2 central planes is the vertical central axis of the stretched blow-molded hollow body 10 of the intermediate container 1 . In the particular example of figure 1 , this central axis C is also the central axis of the cylindrical neck finish 1 1 . In other variants within the scope of the invention, the central axis of the cylindrical neck finish 1 1 is not necessarily the same than the vertical central axis C of the stretched blow- molded hollow body 10, but can be offset from said vertical central axis C. The central axis of the cylindrical neck finish 1 1 is also not necessarily parallel to the vertical central axis C of the stretched blow-molded hollow body 10, and the neck finish is not necessarily cylindrical.
In reference to figure 1 , the stretched-blow molded hollow body 10 of container 1 comprises two opposite recesses 101 that are formed in the side wall 10a of the container 1 . Each recess 101 defines a closed contour and is off-center from the second vertical central plane P2. The stretched-blow molded hollow body 10 of container 1 also comprises two opposite convex and outwardly protruding deformable regions 102 that are formed in the container side wall 10a. Each convex and outwardly protruding deformable region 102 is surrounded by one recess 101 .
In reference to figure 1 , each recess 101 forms an elongated closed contour of maximum vertical length L (maximum dimension of the recess 101 measured in a direction parallel to the central axis C of the container) and of maximum horizontal width W (dimension of the recess 101 measured in a direction perpendicular to the central axis C of the container). Within the scope of the invention, the recess 101 can form a closed contour of any shape, and can form a closed contour that is for example circular or rectangular. The recess 101 does not necessarily defined closed contour that would surround the convex and outwardly protruding deformable regions 102 on the whole periphery thereof, but the recess 101 in another variant, the recess 101 can also extend only on a portion of the periphery of the convex and outwardly protruding deformable regions 102.
In the particular embodiment of the appended figures, the two recesses 101 are identical and are symmetrical, and the two convex and outwardly protruding deformable regions 102 are also identical and are symmetrical, the central plane P1 forming a mirror symmetry plane for the recesses 101 and the convex and outwardly protruding deformable regions 102. Within the scope of the invention, in other embodiments of the invention, the two opposite recesses 101 are neither necessarily identical nor symmetrical, and the two opposite convex and outwardly protruding deformable regions 102 are neither necessarily identical nor symmetrical. The intermediate container 1 can also have only one recess 101 and one convex and outwardly protruding deformable regions 102 surrounded by said recess 101 .
In reference to figure 7 to 15, dimension DR is the maximum dimension of the stretched-blow molded hollow body 10 measured in a gripping region of the container side wall 10a next to and on one side of each convex and outwardly protruding deformable region 102, in an horizontal cross section plane, that is perpendicular to the said first P1 and second P2 central vertical planes, and that is intersecting the recess 101 , and in a direction perpendicular to the first vertical plane P1 . Dimension DL is the maximum dimension of the stretched-blow molded hollow body 10a measured next to and on the other side of each convex and outwardly protruding deformable region 102in the same cross section plane and direction than dimension DR. In the invention dimension DR is smaller than dimension DL, in order to form in the container side wall 10a a gripping region that is more ergonomic. In particular, for an ergonomic gripping, dimension DR will be preferably between 30mm and 70mm, and preferably between 40mm and 60mm.
In reference to figure 17, each recess 101 comprises a first 1010 lateral wall extending between A and B, a second opposite lateral wall 101 1 extending between H and D, and a bottom portion 1012 extending between B and H, and joining said first lateral wall 1010 to said second lateral wall 101 1 . In the particular embodiment of figure 17, the bottom portion 1012 is a flat wall of small width W1 , for example between 1 mm and 2mm. In another variant, the bottom portion 1012 can be also a small concave arc-shaped portion 1012 having a small radius of curvature as shown on the variant of figure 18.
More particularly, said first 101 ) and a second opposite 101 1 lateral walls of said recess 101 are flat or smoothly curved without any hinge region.
Referring to figures 7 to 18, each convex and outwardly protruding deformable region 102, before inversion thereof, is represented in dotted lines.
Each convex and outwardly protruding deformable region 102 comprises an invertable lateral wall 1020 (figure 17/ between D and E) and a convex front wall 1021 (figure 17/ between E and E) that is an extension of this invertable lateral wall 1020. Said invertable lateral wall 1020 is an outward extension of said second lateral wall 101 1 of the recess 101 and extends outwardly beyond the first lateral wall 1010 of the recess 101 .
More particularly, the orthogonal projection on the first central plane
P1 of each outwardly protruding deformable region 102 is located within the container.
On the whole periphery of the convex and outwardly protruding deformable region 102, the junction H between the bottom portion 1012 and the second lateral wall 101 1 of each recess 101 forms an hinge that can be used for mechanically inverting said convex and outwardly protruding deformable region 102 and the second lateral wall 101 1 of the recess 101 by pushing them inwardly in order to form an ergonomic and integrally molded deep handgrip G. The final container 10f figure 4 is thus obtained by pushing inwardly, towards the first vertical central plane P1 , each convex and outwardly protruding deformable region 102 and each second lateral wall 101 1 of the recess 101 in such a way to mechanically invert them and form the ergonomic and integrally molded deep handgrip G.
In reference to figure 17, once the convex and outwardly protruding deformable region 102 (in dotted lines) and the second lateral wall 101 1 of the recess 101 have been mechanically inverted, it forms a concave grip region G, that is substantially the mirror image of the convex and outwardly protruding deformable region 102 and of the second lateral wall 101 1 of the recess 101 with respect to a symmetry plane P3 that is tangential to aforesaid hinge H.
Said mechanical inversion is performed in a boxing step subsequently to the aforesaid first blow molding step. This boxing step can be carried out either in the blow mould cavity MC that has been used for making the intermediate stretched blow-molded container 1 or in a different and specific boxing mold. The boxing step is carried out by moving inwardly a moveable plug in the mould in contact with the front wall 1021 of the convex and outwardly protruding deformable region 102, while the inside of the intermediate stretched blow-molded container 1 is preferably filled with air under a certain pressure for maintaining an internal pressure inside the container, for example a pressure of about 20 bars. The mechanical force exerted by the moving plug onto the front wall 1021 of the convex deformable region 102 (see figure 17/ arrow I) is for example, but not necessarily, perpendicular to central plane P1 . It can be exerted by a translational movement and/or a rotational movement of a plug actuated by a hydraulic, electric or pneumatic jack. During this boxing step, the deformable region 102 can be slightly stretched or on the contrary can be not stretched.
The boxing step is preferably carried out while the container is at a temperature below the glass transition temperature Tg of the polymer constituting the container (cold boxing). Within the scope of the invention, the boxing step can be however also carried out at a temperature above the glass transition temperature Tg (hot boxing step).
Once the deep concave hand grips G are formed in the final container
V, the air under pressure inside the final container 1 is exhausted in order to release the internal pressure inside the container V, the mould cavity is opened, and the final container V is removed from the mould cavity.
As shown on figures 10 and 17, each concave grip G resulting from the inversion of the convex an outwardly protruding deformable portion 102 and of the second lateral wall 101 1 of the recess 101 is deep and suitable for ergononnically receiving the fingers or thumb of a hand. Preferably, at least in a portion of the deep grip concave portion G ( see figures 10 and 17) the minimum depth DP of the concave grip portion G (figure 17) measured in a direction perpendicular to the first central plane P1 is at least 15mm, and preferably at least 20mm and/or is more than 50%, and preferably more than 70% of half the aforesaid maximum dimension DR.
In a preferred embodiment, the minimum distance D2 (figure 17) between the bottom wall 1021 ' of each deep concave portion G and the central plane P1 is preferably not more than 5mm, and more preferably not more than 2mm. In another embodiment of the invention (not shown on the appended drawings) the two bottom walls 1021 ' of the two concave deep concave portions G can be in contact with each other, and if needed can be welded together or connected by another way
In order to improve the blowing of the intermediate container 1 , the depth of the recess 101 is preferably not constant on the whole periphery of the recess. More particularly, as shown on figures 10 and 17, the recess 101 comprises a first portion 101 a that is far away from the second vertical central plane P2 and a second portion 101 b that is closest to the second vertical central plane P2, and the depth DP1 of said recess 101 measured in said first portion 101 a of the recess is smaller than the depth DP2 of said recess 1 1 measured in said second portion 101 b of the recess.
More preferably the depth DP1 of said recess 101 measured in said first portion 101 a has to be very small and is preferably not more than 10mm, more preferably not more than 5mm and even more preferably between 0mm and 2mm. When the second portion 101 b of the recess 101 that is closest to the second central plane P2 is offset from this central plane P2, the depth DP2 thereof is preferably not more than 10mm. In return, when the second portion 101 b of the recess 101 that is closest to the second central plane P2 is actually included in this central plane P2, depth DP2 can be more than 10mm, and the only limitation for depth DP2 is the preform diameter. Different trials have shown also that, for a better boxing of the intermediate container, the angle a (figure 17) between the invertable lateral wall 1020 of the convex and outwardly protruding region 102 and the second plane P2 is preferably not less than 10°. The distance d1 between the first central plane P1 and the bottom of the first portion 101 a that is far away from second central plane P2 is also preferably smaller than or equal to the distance d2 between the first central plane P1 and the bottom of the second portion 101 b of the recess 101 that is closest to the second central plane P2.
Moreover, for a good stretched blow molding of the intermediate container 1 , the angle β between the symmetry plane P3 (figure 17) and the first central plane P1 is preferably not more than 15°. In addition, the gripping of the container is improved when the angle a is large and the angle β is small.
The invention is not limited to the particular design of intermediate container 1 and final container 1 ' of figures 1 to 18. Figures 19 to 25 shows other examples of horizontal cross section of intermediate container 1 and final container V also covered by the invention. On these figures 19 to 25, the convex outwardly protruding deformable region 102 of the intermediate container is represented in dotted lines. More particularly, the orthogonal projection on the first central plane P1 of each outwardly protruding deformable region 102 is located within the container.
On figure 19, the bottom portion 1012 of the second portion 101 b of the recess 101 is intersected by the second central plane P2, and the symmetry plane P3 is parallel to first central plane P1 ( β = 0) .
On figures 20 to 23, the bottom portion 1012 of the second portion
101 b of the recess 101 is intersected by second plane P2, and the angle β between the symmetry plane P3 and first central plane P1 is about 5° for figure 20, about 10° for figure 21 and about 15° for figures 2 and 23.
On figure 24, the two bottom portions 1012 of the first 101 a and second 101 b portion of the recess 101 are offset from the second central plane P2 and are positioned respectively on each side of said second central plane.
On figure 25 the two bottom portions 1012 of the first 101 a and second 101 b portion of the recess 101 are offset from the second central plane P2 and are positioned on the same side of said second central plane P2.
In the two embodiments of figures 23 and 24 , the deep concave grip G of the final container 1 advantageously comprises undercuts regions U (in hatched lines), that is to said regions U that cannot be reached from the outside of the container by a rectilinear axle that is moved in a direction perpendicular to first central plane P1 . Usually, the blow molding of such container having undercuts would need the use of a complex blow molding mould having sliding parts for forming the undercut and enabling the removing of the container outside the mould.
More particularly, in the variants of figures 23 and 24, the undercut region U of the deep concave grip G is located on one side of the second vertical central plane P2 and at least a part of the deep concave grip G is located on the other side of the a second vertical central plane P2.