Patent Publication Number: US-9895826-B2

Title: Preform, container and method for forming a container

Description:
FIELD OF THE INVENTION 
     This disclosure is directed to a preform and to a method for blow moulding a container. 
     DESCRIPTION OF RELATED ART 
     Blow moulding is a well know technique for manufacturing containers, such as but not limited to bottles for beverages. In this technique a plastic preform is moulded, for example by injection moulding. The preform is heated to a temperature below the melting temperature of the plastic. A blow moulding tool is inserted into the preform, which is placed inside a blow moulding mould, having the shape of the desired container. With the blow moulding tool the preform is stretched and then the preform is blown to the desired shape against the inner surface of the mould. 
     In some cases it is desirable to have a lid element attached to such blow moulded container. 
     In WO 2008083782 a container is shown having a valve assembly provided in a neck portion by using a welding method, such as ultrasonic welding or laser welding. This valve assembly is welded into the neck region after blow moulding the container. 
     In WO 2008098937 a container is shown having a valve assembly provided in a neck portion by using a laser welding method. This valve assembly is welded into the neck region after blow moulding the container, by directing a laser beam though a wall of the neck portion onto an annual part of the valve assembly. 
     It is desirable to provide an alternative method and preform for manufacturing blow moulded containers having a lid element attached thereto. 
     SUMMARY OF THE INVENTION 
     In a first aspect the present description is related to a preform for blow moulding a container, wherein a lid element is attached to the preform before blow moulding a container from the preform. 
     In another aspect the present description is directed to a method for blow moulding a container from a preform. The method can comprise the step of first attaching a lid element to the preform and then blow moulding the container from the preform. 
     In still another aspect the description is directed to a container, blow moulded from a preform of this description or using method steps according to the description. 
     Other aspects of preforms and methods are further disclosed in the dependent claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to further clarify the subject of this disclosure, embodiments of a preform, method and container are discussed hereafter, with reference to the drawings, which are only schematically representations. In these drawings: 
         FIG. 1  schematically shows a first embodiment of a preform; 
         FIG. 2  schematically shows a lid element, in cross section and partially in bottom view; 
         FIG. 3  schematically shows the preform of  FIG. 1  with a lid element attached at the neck portion; 
         FIG. 4  schematically shows a second embodiment of a preform; 
         FIG. 5  schematically shows a third embodiment of a preform; 
         FIG. 6  schematically shows a preform assembly; 
         FIG. 7  schematically shows a further preform assembly; 
         FIG. 8  schematically shows a container manufactured according to the description; and 
         FIG. 9  schematically shows an alternative embodiment of a container manufactured according to the description, with connecting means. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION 
     In this description embodiments are described with respect to plastic containers, blow moulded, such as stretch blow moulded, from a preform, wherein a preform can for example be manufactured by injection moulding or extrusion. These containers can be used for example but not limited to storage of beverages, such as but not limited to carbonated beverages. Obviously the containers can be made of other materials, such as blends of plastics, combinations of plastics and metals, such as metal foils, scavengers and the like. The embodiments are disclosed only as exemplary embodiments and are not to be considered as limiting the disclosure in any way. 
     In this description blow moulding has to be understood as at least comprising but not limited to stretch blow moulding, wherein a preform is heated, stretch lengthwise and blown into a desired shape. During lengthwise stretching the preform can already be blown to some extent. 
     In this description a preform, which can also be a parison, has to be understood as at least including but not limited to an element injection moulded from plastic, to be blown into a blow moulded container. In this description preforms shall be described for blow moulding containers which basically have a bottle shape, including a neck portion, a body portion and a bottom portion, but it will be obvious to any skilled person that different shapes of containers can be made using different shapes of preforms falling within the same inventive concept. A preform can be single or multi layer. A multi layer preform can be manufactured using well known techniques, such as but not limited to co-injection, co-extrusion or over moulding. A multi layer preform can have a delaminating layer or layers. 
     In this description wording like about and substantially should be understood as meaning that variations of a given value it refers to are allowable within the given definition, which variations can at least be 5%, preferably at least 10% and more preferably at least 15% of the given value. 
     In this description preforms and containers will be discussed made of PET or PET blends. However, preforms and containers according to the present disclosure could also be made of different materials, blends or combinations of materials, such as but not limited to polypropylene or polystyrene, PEN, polyethylene, Polycarbonate, PBT, blends of the forgoing or combinations thereof. In case of PET or PET blends, standard PET has to be understood in this respect as at least including PET without added additives for preventing crystallisation of the PET during forming such as injection moulding of a preform. 
     In this description reference shall be made to containers for holding and dispensing beverages, especially carbonated beverages such as beer and soft drinks. However other contents can be stored and dispensed using a container according to this description. 
     In the present disclosure preforms can be formed of a plastic material that can be stretch blow moulded into a container having a relatively thin wall or combination of walls, wherein the preform is substantially amorf, whereas the bottle is at least partly crystalline. Preferably the preform is formed of a material substantially free of crystallisation preventing additives, such as glycol. It has been recognised that such additives can be favourable in injection moulding a preform substantially amorf, but these additives remain in the blown container, which is detrimental to the strength and/or stiffness of the container. The preforms are preferably injection moulded having a wall thickness sufficiently small to substantially prevent crystallisation of the plastic material. 
     For containers stretch blow moulded from a preform, having an internal volume, especially a volume of more than 3 liters, the opening of a preform is to be relatively large, for example 2 cm or more. Providing a rug element with a smaller opening; enables easy placement of a valve or valve assembly with smaller dimensions. For example, when standard aerosol type valves, spray can type valves or the like are used, for example to be clinched, such is advantageous. 
     In  FIG. 1  a preform  1  is shown, injection moulded in a commonly known method. The left side of  FIG. 1  shows the preform  1  in cross section, the right side in side view. The preform  1  can have a substantially cylindrical wall  2  with a closed first end  3  and a neck portion  4  at the opposite second end  5 . An inner volume  6  extends from a neck opening  7  into an inner space  8 . The inner space  8  is largely defined by an inner surface  9 . The wall  2  surrounding the inner space  8  can have a thickness T w  which can be for example the same or larger than the thickness T n  of the neck portion  4 . On an outside  10  of the neck portion  4  grip elements  11  can be provided, for example one or two flanges  12 , and/or screw threads  13 . The or each flange  12  can extend substantially perpendicular to a longitudinal axis L of the preform  1 . If there is more than one such flange  12 , they can extend substantially parallel to each other. In the embodiment of  FIG. 1  one such flange  12  is shown. Flanges  12  are common and can be used for handling the preform  1  and/or a container  23  blown from it. Moreover these can be used for rigidifying the neck portion  4 , in order to maintain its shape and dimensions as good as possible. Another aspect can be that these flanges allow other elements to be attached to the neck portion, such as but not limited to lids, dispense mechanisms, top ring structures and the like. Embodiments can be comprised having flanges that are of different diameters. 
     In the embodiment of  FIG. 1  the inner surface  9  extends directly and continuously into the neck portion  4 . Apart from the part  14  at the first end  3 , which can be substantially spherical or shaped for forming a petal shaped bottom, the inner surface  9  can be substantially cylindrical. The neck portion  4  can have, at the first end  3 , a substantially flat, circular end surface  15 . In another embodiment the neck portion can have a differently shaped end surface  15 , for example but not limited to partly or completely conical, recessed or toothed. In another embodiment the end surface can have a shape different from circular, such as but not limited to oblong, oval, square, rectangular or multi angled. 
     In  FIG. 2  a lid element  16  is shown, partially in cross section. In this embodiment the lid element  16  is substantially ring shaped, having a peripheral ring  17  and a central opening  18 . The central opening  18  can be provided in a tubular portion  19  extending from or through the ring  17 . An outer surface of the tubular portion  19  can in such an embodiment be useful in attaching elements to the lid element  16 , such as but not limited to a valve  20 , schematically shown in  FIG. 2  in broken lines, clinched to the portion  19 , a lid, an aeration device or the like. A lid element  16  can be made of a plastic material similar to that of the preform  1 . In another embodiment the lid element  16  can be made of a material different from the material of the preform. In an embodiment the lid element  16  can be made partly or entirely of metal. In an exemplary embodiment the preform and the lid element can both be made of PET or PEN or a blend containing at least PET or PEN. In an embodiment such blend can comprise at least 50 weight % of PET and/or PEN. In a further embodiment the blend can comprise at least 75 weight % or PET and/or PEN. In an embodiment the preform  1  and/or the lid element  16  can be made of a plastic material having CO 2  and/or O 2  barrier properties. The preform  1  can have multiple layers, one of which, especially an inner layer, can be at least partly detachable from the further layer(s) of the preform  1 . In an embodiment the preform  1  and the lid element  16  can be made of materials that can be welded or glued. 
     In  FIG. 3  a preform  1  is shown, with a lid element  16  attached at the neck portion  4 . In this embodiment the lid element  16  is placed with the ring  17  on the end surface  15  permanently. In an embodiment the lid element  16  can be attached to the surface  15  by welding. In an embodiment the welding can be achieved by ultrasonic welding. In still another embodiment the welding can be achieved by a welding technique chosen from the group of ultrasonic welding, laser welding, friction welding, spin welding or pressure welding. In still another embodiment the lid element  16  can be connected to the preform  1  by gluing. In another embodiment the lid element  16  can be permanently or releasably connected to the preform  1  by other means, such as but not limited to a snap connection, press fit, friction locking, screw thread, bayonet locking or other such means known in the art for connecting two elements. 
     As can be seen in  FIG. 3  the lid element  16  allows access into the inner volume  6  of the preform  1 . In an embodiment the access to the inner volume  6  can be through the lid element  16 , especially through the opening  18  therein. The access can be available for a blow moulding tool  21 , schematically shown in  FIG. 3  in broken lines. Such blow moulding tool  21  can for example be an element having a longitudinal axis L t , substantially coinciding during use with the longitudinal axis L of the preform  1 . A forward end  22  can be pushed against the first end  3  of the preform  1 , which can be heated to a temperature below the melting temperature of the plastic material of the preform  1 , but sufficiently high to make the material pliable, such that the preform  1  can be stretched in the longitudinal direction. Then gas such as air can be forced through the tool  21  and into the inner volume  6  of the preform, blowing up the preform  1  to a container  23  of a desired shape and dimension. In an embodiment the outer surface of the tool  21  can lie against the inner wall of the preform before blowing. In another embodiment the outer surface of the tool  21  can lie at least partly spaced apart from the inner wall of the preform  1 . 
     In an embodiment of the present description first a preform  1  is injection moulded. A lid element  16  can be manufactured separately, for example by machining, pressing or injection moulding. In a different embodiment the lid element  16  can be formed together with the preform, for example injection moulded with a collapsible core or in a two or more component (2K) injection moulding process. In still another embodiment the lid element  16  can be hinged to the preform, for example to a neck portion  4  thereof, and/or a valve  20  can be hinged to the ring  17 , as shown in  FIG. 4 , and forced over the opening of the neck portion after injection moulding and cooling. In a further embodiment the lid element  16  can be mounted on the neck portion  4  in a different way, for example by welding, such as spin welding, ultrasonic or laser welding, conventional welding, screwing, bayonet locks, snap elements such as a snap ring or snap hooks or a press fit. In another embodiment the lid element can be glued to the preform. The lid element  16  can be mounted or provided for within the apparatus in which the preform  1  and/or the lid  16  is or are made. 
     After or directly prior to mounting the lid element  16  to the preform  1  the preform  1  can be moved to a blow moulding station, where the preform  1  can be blown into the desired container  23 , as for example shown in  FIG. 8 . Then the container  23  can be moved to a filling station, where a beverage can be injected into the container in a known and suitable manner. The preform  1  is preferably provided with the lid element  16  before blow moulding, especially before shipment from the one or more injection moulding apparatus. This may make the manufacturing easier and prevents shipping of fully or even partly blown but, apart form air, empty containers such as bottles or kegs, which would be environmentally unfriendly. Moreover, by providing the lid  16  on the preform prior to filling, especially prior to shipment thereof to a bottler, the lid elements  16  do not have to be stored and shipped separately and the providing of the lid elements  16  does not have to be done in a wet or otherwise possibly hostile environment. 
     After filling the container  23  with the beverage in a further station other elements can be added to the container  23 , such as a closure, closing the container  23 , or a valve or valve assembly  20 , such as for example but not limited to a combination of a beverage valve and a gas valve. Such valve assembly can be a known type valve assembly such as a Sankey type or a flat head type assembly. In another embodiment a dispensing device, such as a riser pipe  26  and connector or locking element  27  can be provided in the lid  16 , as for example shown in  FIGS. 7 and 8 , for allowing the container  23  to be connected to a dispensing device  30 , as for example shown in  FIG. 8 , for dispensing the beverage. Such dispensing devices are for example known from EP 1003686 or WO2004/050539 or EP 1626925. Other dispensing devices can be for example regular devices having a tapping head to be connected to the neck  4  of the container  23 , for introducing a pressure gas such as CO 2  into the container and allowing beverage to be dispensed form the container, for example to a beverage engine, a tapping cock  30 A or the like. In still another embodiment a valve  20  such as an aerosol type valve can be provided in the lid  16 , for dispensing the beverage and in an alternative embodiment also for introducing a pressure gas into the container  23 . Such valve is for example known from WO 2008/048098. 
     In an embodiment the preform  1  can be designed for blow moulding a container  23  having a content of between 1 and 10 liters, for example between 2 and 6 liters. In an embodiment the container  23  can have a content of about 5 liters. In an embodiment the preform  1  can be designed for stretch blow moulding a container  23  having a content of over 10 liters, for example between 10 and 50 liters. In an embodiment the container can have a content of between 15 and 30 liters, for example about 17 to 20 liters. A preform  1  according to the disclosure can be made of a single material, such as but not limited to PET, PEN, PP, PS, PC or another thermoplastic material and/or crystallizing and/or stretch blow mouldable plastic material or combinations of such materials. In another embodiment the preform can be multi layered, comprising layers of a similar or different materials such as plastics or plastic blends. Multi layer bottles are known in the art and shall not be discussed here extensively. An example of a multi layer bottle and a dispensing device for such bottle are disclosed in WO 92/012926. The content of this application is incorporated herein by reference, at least for the dispensing devices, bottles and materials disclosed therein. 
     The preform  1  can have a neck portion  4  with an internal cross section perpendicular to a longitudinal axis A-A, which cross section has a surface area formed by or comparable to a circular area having a diameter D of more than 2 cm, for example a diameter between 2 and 10 cm, more specifically between 3 and 6 cm, such as for example about 49 mm. The lid element  16  can have a central opening  18  with an inner surface area formed by or comparable to a circular surface having a diameter D 1  for example between 0.5 and 6 cm, for example between 0.5 and 4 cm, the area being smaller than the area of the opening  7  of the neck portion  4 . The opening  18  can be circular and can be designed to have a valve such as an aerosol valve  20  fitted in or over it. In another embodiment the lid element  16  can have different openings  18 , for example two, side by side, such that for example in one of the openings  18  a dispensing element can be fitted, such as a valve  20  with or without a riser pipe  26  for dispensing the content of the container  1 , such as a beverage, for example beer, whereas in the other opening  18 A a gas inlet can be attached, such as for example a CO 2  source or an air pump  31 A. 
     In an embodiment the preform can be injection moulded, after which the lid element  16  is provided on and/or in the preform  1  or one of the preforms in a preform assembly. Then the preform(s) can be transferred to a bottling line, in which preforms are in line blow moulded and filled with for example a beverage such as but not limited to beer. In an embodiment then a valve assembly  20  or a dispensing assembly  30  or part thereof can be placed in and/or on the opening  18 . 
     In  FIG. 4  a preform  1  is shown, schematically in cross section, a lid element  16  in the form of a ring  17  with a valve  20  attached to it via for example an integrated hinge  32 A is shown. In this embodiment the ring  17  is mounted on the preform  1 , for example welded to it, wherein the valve  20  is folded away from the central opening  18 , such that the container  23  can be blow moulded from it and a filling pipe can be introduced into the container  23  through said opening  18 , where after the valve  20  can be folded into the opening  18 , closing off the container  23 . In the embodiment shown the valve  20  is enclosed in a clamping tube that can be clamped into the opening  18 , as is schematically shown in  FIG. 4  on the right hand side. The valve  20  is preferably pushed into the opening  18  after blow moulding a container  23  from the preform and filling the container  23 . In  FIG. 4  schematically a shoulder part  23 P of a container is shown. 
     In  FIG. 5-7  preform assemblies  31  are shown, comprising a first preform  1 A and a second preform  1 B. The first preform  1 A can have been inserted into the second preform  1 B or vice versa. In an alternative embodiment one of the first and second preforms  1 A, B can have been injected in or on the other of the two preforms  1 A, B. The preforms  1 A, B can have been injection moulded or otherwise formed separately, from the same or different materials. The preforms  1 A, B can have some or all of the properties of preforms described before. 
     In the embodiment of  FIG. 5  the first preform  1 A can have a substantially cylindrical wall  2 A with a closed first end  3 A and a neck portion  4 A at the opposite second end  5 A. An inner volume  6  extends from a neck opening  7  into an inner space  8 . The inner space  8  is largely defined by an inner surface  9 . A lid element  16  such as a ring  17  has been mounted on the neck portion  4 A, having a central opening  18  with a diameter D i  smaller than the diameter D ni  of the neck portion  4 A and/or has an outer diameter D o  larger than the outer diameter D no  of the neck portion  4 A. The lid element  16  can again have been mounted in any suitable way, for example as disclosed here above. The second preform  1 B can have a substantially cylindrical wall  2 B with a closed first end  3 B and a neck portion  4 B at the opposite second end  5 B. The neck portion  4 B can be wider than a body forming portion thereof, defined by the wall  2 B. A shoulder  32  is provided between the neck portion  4 B and the wall  2 B, on which the lid element  16  or a flange or partial flange extending from the neck portion  4 B can rest, when the first preform  1 A is inserted into the second preform  1 B. This way the first preform  1 A can for example be suspended in the second preform  1 B. In  FIG. 5  the outer surface of the first preform  1 A is spaced apart over at least part of the surface from the inner surface  9 B of the second preform  1 B. A space  33 , for example filled with a gas such as air can be provided between said two surfaces. This space  33  can be closed off to the environment by the ring  17 . Upon blow moulding the container from the preform assembly  31  the space  33  can be maintained, such that the container may become more rigid and light. In another embodiment the space  33  may be in communication with the environment, for example through one or more openings  18 A ( FIG. 9 ) in the ring  17  and/or by leaving some space between at least part of the ring  17  and the surrounding wall of the neck  4 B of the second preform  1 B. This way pressure can be relieved from the space  33  and/or in the container  23  a pressure fluid such as but not limited to gas, for example air, can be brought into the space  33 , for compression off the container part  23 A blow moulded from the first preform  1 A. In still another embodiment the space  33  can be filled with a curable fluid or with a coating, such as but not limited to a coating providing a barrier against migration of gas such as O2 into and/or out of the container, a scavenger for such gas, for example for O2, and/or a colouring. The coating can be provided as a layer on or in a preform, can be a foil such as an in mould label, and can for example extend over all of the space or only part thereof. 
     In  FIG. 6  the preform assembly  31  comprises a first preform  1 A that fits relatively snugly into the second preform  1 B, the ends  5 A, B thereof lying substantially in the same plane. A lid element  16  comprising an opening  18  is provided on at least one of the two preforms  1 A, B. In the embodiment shown the lid element  16  has a peripheral ring  17  extending outside the outer surface  9 C of the neck portion  4 B. Preferably the lid element  16  is at least connected to the second preform  1 B, thus enclosing the first preform  1 A within the second preform  1 B. 
     In  FIG. 7  the preform assembly  31  comprises a first preform  1 A that fits into the second preform  1 B, the end  5 A of the first preform  1 A lying below the end  5 B of the second preform  1 B. A lid element  16  comprising an opening  18  is provided on at least one of the two preforms  1 A, B, preferably the first preform  1 A. In the embodiment shown the lid element  16  has a peripheral ring  17  extending to or preferably slightly outside the outer surface  9 C of the neck portion  4 A. The peripheral ring  17  can be slightly flexible or compressible, such that the lid element  16  can be press fitted into the opening  7  within the neck  4 B of the second preform  1 B. Thus the first preform  1 A can be easily fixated inside the second preform  1 B, for example storage and transport and during (stretch) blow moulding. 
     The wall thickness of at least a body forming portion of the preform or preforms is preferably such that the preform is substantially amorphous. The container blow moulded there from is preferably stretched such that the plastic material is substantially crystalline. The plastic material preferably is substantially free of crystallisation preventing additives, such as but not limited to glycol or similar additives. Preferably the preform or preforms have a maximum wall thickness of less than 8 mm, preferably less than 6 mm, especially but not exclusively when the plastic material is substantially PET or a PET blend. 
     In  FIG. 8  a container is shown, blow moulded, such as but not limited to stretch blow moulded from a preform  1  or preform assembly  31 . A lid element  16  is provided on the neck  4 . A valve  20  is provided in the opening  18 , which can be an aerosol type valve. The valve  20  can be clinched or clamped on the lid element  16 , for example in the tube or ring  19 , using a connector or locking element  27 , for example a clinch plate. A riser pipe  26  is connected to the valve  20  for dispensing the beverage from the inner volume  6  of the container  23 . In  FIG. 8  a pressure regulator  34  is provided in the inner volume  6  of the container, from which gas such as CO2 can be introduced into said volume  6 , in order to keep the pressure within the container  23  at a desired level or within desired limits, for example at or near a equilibrium level of gas in the beverage. In such embodiment the container can be self regulating. In another embodiment the pressure regulator can be omitted and gas can be introduced via for example the valve  20  or another opening or valve into the inner volume  6 . 
       FIG. 9  shows schematically part of a container  23  blow moulded, such as stretch blow moulded from a preform  1  or preform assembly  31  such as discussed before. In this embodiment an inner container part  23 A is provided, blow moulded from a first preform  1 A, and an outer, second container part  23 B blow moulded from the second preform  1 B. At least a part of the container parts  23 A, B are not interconnected or at least releasable from each other. A lid element  16  is provided on the neck  4 A of the inner container part  23 A, resting on a shoulder  32  of the second container part  23 B. The inner container part  23 A is at least partly flexible. The container  23  preferably has been blow moulded integrally from the first and second preforms  1 A, B. At least one opening  18 A is provided in the lid element, opening into a space  33  between the inner and outer container parts  23 A, B. A lid  40  is provided over the neck  4 , clamped under the flange  12  with a peripheral portion  41 . A valve  20  is provided in the lid  40 , surrounded at least partly by a skirting  42 . A first seal  43  is provided between the end  5 B of the neck  4 B of the outer container part  23 B, whereas a second seal  44  is provided between the lid element  16  and the lower end of the skirting  42 . Thus a space  45  is provided around the skirting  42 , in fluid connection with the or each opening  18 A. 
     In the embodiment of  FIG. 9  a pump  31 A is connected to a second opening  18 B in the lid  40 , opening into the space  45 . Through this pump pressurised fluid, such as air can be introduced into the space  45  and from said space  45  through the opening  18 A into the space  33  between the container parts  23 A, B, as indicated by the arrows A, compressing the inner container part  23 A at least partly, for forcing the beverage from the inner volume  6  into the dispensing device  30  through the valve  20 . 
     The present disclosure is not limited to the embodiments disclosed or discussed herein by way of examples only. Other embodiments can fall within the inventive concept as defined by the claims. For example any combination of parts and features of the embodiments disclosed are considered to have been disclosed in this description. In another embodiment the preform can have an opening at two opposite ends, wherein a lid element  16  is provided at at least one of the openings. For example one end can have a neck portion  4  and the opposite end a foot portion with an opening in which a valve element is provided as a lid element  16 . Another example can be a lid element  16  including a valve element or at least part thereof, wherein a blow moulding tool can be introduced through the valve element or part thereof or can be connected to it for blowing the preform into a container. In an embodiment the lid element  16  can close off only part of the neck portion  4 , such that the opening  18  is at least partly defined by the lid element and partly by the neck portion. These and other embodiments such as variations are considered to have been disclosed herein.