Patent Publication Number: US-2017349337-A1

Title: Cap with a cutting element

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of U.S. patent application Ser. No. 14/900,549 filed on Dec. 21, 2015, which is a U.S. National Stage application of International Patent Application No. PCT/EP2014/062535 filed on Jun. 16, 2014, which claims priority to Swedish Patent Application No. 1350756-1 filed on Jun. 20, 2013, the entire contents of all three of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The invention generally relates to the field of packaging technology. More particularly, the invention relates to a cap with a cutting element. The invention also relates to a spout arranged to interact with the cap, a bottle provided with the spout, and a method for applying the cap onto the spout. 
     BACKGROUND OF THE INVENTION 
     Within the field of food packaging, and packaging of any perishable product, it is of concern to contain the product in a safe way until it reaches the end consumer. Even more so, the end consumer should preferably be able to judge whether the product is safely contained or not before acquiring the product. This is particularly true for the closure of the package. A regular screw-cap closure may be opened and reclosed without causing any visible leakage, yet breaking the hermetic seal may hamper the quality of the product in a dramatic way. This is one of the reasons to why tamper evidence has been introduced. A common tamper evidence is the well-known tamper ring, which is torn of the cap as the container is opened for the first time. The functionality of the tamper ring may vary, and there are numerous options available. Also, there are other tamper evidences too, such as lacquer seals and various shrink plastic arrangements, etc. 
     The closure of a packaging container has to fulfill several demands. It should provide adequate barrier properties, such that liquids or gas does not pass into or out of the container before it is opened for the first time. Also, it should provide adequate resealing properties such that no leakage occurs after the first opening. Additional demands are that it should be easy to open, efficient to manufacture and appealing to the eye. 
     A thorough overview of the technical field is disclosed in WO2008148764 to SACMI, and it is considered that the skilled person would have no problem in realizing the present invention after studying the teachings disclosed herein combined with the prior art. One example is that the present invention does not discuss moulding of plastic closures. Even if this knowledge is essential for the manufacture of plastic closures, it does not define the present invention in the light of prior art and is therefore considered superfluous for the purposes of disclosing the present invention in a sufficiently detailed manner for the skilled person to practice it. 
     SUMMARY 
     In an effort to provide an improved opening device the present invention, according to one aspect thereof, provides a cap arranged to interact with a spout. The cap comprises a top portion, a sidewall portion depending from the top portion and formed in one piece therewith, the sidewall portion comprising an interior threading arranged to interact with exterior threading of the neck during an opening operation and during a closing operation. Further, the cap comprises a tamper evidence removably attached to the sidewall portion, and the sidewall portion further comprises cutting elements having a first end hingedly attached to the sidewall portion and a free end portion arranged to interact with a membrane portion of the spout, wherein the hinged attachment allows for the cutting element to pivot in an axial direction. The cap is characterized in that the free end portion has a blunt tip and a comparatively sharper cutting edge on a lateral side of the free end portion. This design facilitates initial arrangement of the cap onto a neck or spout, and it also provides an adequate operation during use of the device. 
     According to one or more embodiments the blunt tip of the cutting elements are arranged to penetrate the neck portion in the region of the membrane portion during a first sequence of a first opening operation, and wherein the cutting edge is arranged to cut the membrane portion from the neck portion during later stages of the first opening operation, and wherein the cutting elements are arranged to hold the removed membrane portion in an area between the cutting elements and the top portion. Before being utilized the first time for opening purposes the cutting elements will lean onto the neck or spout of the packaging container, directed in an opening direction (towards an opening end of the packaging container). As the cap is unscrewed the cutting element will pivot and eventually be forced towards a weakened region of the membrane and penetrate the same, in a way to be further explained in the detailed description. 
     According to one or more embodiments the cutting elements comprises a local protrusion extending from an axial side of the cutting element, resulting in advantages to be described in the detailed description. In a related embodiment the local protrusion is arranged at an axial side facing the tamper evidence and/or to a side remote to the cutting edge. 
     In one or several embodiments the local protrusion may have an elongated extension in a radial direction, such that it may be in contact with a newly cut edge of the neck during the first opening operation. 
     In still further embodiments stop elements extend from the top portion along the sidewall portion, preferably being formed in one piece therewith, the stop elements being configured to contact a cooperating circumferential counter element of the neck to limit the movement of the cap in an axial direction. The use of an additional stop element not interfering with other functional portions of the cap will enable tailormade solutions in these other functional portions. 
     It is preferred, though not a necessity, that the cap is moulded in one piece. A suitable material for the cap is polypropylene, though the materials or compounds of materials are possible. 
     According to another aspect of the present invention it relates to a method for arranging a cap onto a neck, comprising the steps of arranging the cap in a cap-holder device, aligning the cap with a neck, positioning the cap onto the neck by means of a relative axial movement. 
     In one or more embodiments the step of positioning the cap also comprises a relative rotational motion. When screwing the cap into position an extra added value is obtained from embodiments of the cap including the protrusions. 
     According to one or several embodiments the method further comprises the preceding step of moulding a neck onto a paper-based container sleeve. 
     The cap may be made of polypropylene. Since polypropylene is harder than High Density PolyEthylene (HDPE) a cap made of polypropylene may advantageoulsy be used with a spout made of HDPE. An advantage of having the spout made of HDPE is that the shelf life of the liquid food stored in a bottle provided with the spout may be prolonged since the liquid food is less affected by the outside conditions due to the more resistent material in the spout. More particularly, a spout made of HDPE has a lower Oxygen Transmission Rate (OTR) than, for instance, a spout made of Low Density PolyPropylene (LDPP), which has the positive effect that less oxygen will enter the bottle or the package provided with the spout through the spout, which in turn has the effect that the liquid food in the bottle or package may be stored for a longer period of time without being unsafe to consume. 
     Another advantage of having a spout made of HDPE is that a more roboust package is achieved having the effect that more packages or bottles provided with spouts made of HDPE can be piled on top of each other. 
     There are other possible solutions for obtaining the right performance for the spout and the cap. One example is that instead of using a pure material, such as PP for the cap or HDPE or LDPE for the spout a compound, mixture or layered construction may be used. E.g. an inferior pure material may be improved by additives, and by adding an extra barrier layer the OTR may be adjusted. Such considerations may be relevant for various applications of the present invention in terms of being relevant for caps and spouts as such, yet they are not important for the understanding of the present invention as defined by the claims 
     According to a fifth aspect a method for packaging liquid food in a bottle is provided. The method comprising forming a body portion of said bottle in the form of a sleeve of a carton-based laminate, forming a top section of said bottle, said top section comprising a spout according the second aspect, joining said top section to said body portion, filling said bottle with liquid food via an open end of said bottle, sealing said open end of said bottle, and applying a cap according to the first aspect onto said spout according to the fourth aspect. 
     The step of forming said top section of said bottle may comprise molding said spout. 
     The spout may be applied onto said spout such that a spout neck combination is formed, and said forming said top section of said bottle may comprise molding a top section such that said spout of said spout neck combination is joined to said top section. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above, as well as additional objects, features and advantages of the present invention, will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments of the present invention, with reference to the appended drawings, wherein: 
         FIG. 1  illustrates a carton-based bottle having a top section made of plastic and a body made of carton-based laminate. 
         FIG. 2  illustrates a cap according to a first aspect of the present invention. 
         FIG. 3  illustrates a neck according to a second aspect of the present invention. 
         FIG. 4  illustrates a cap/neck assembly according to a third aspect of the present invention. 
         FIG. 5  illustrates a first side of a cutting element according to one embodiment thereof. 
         FIG. 6  illustrates the cutting element of  FIG. 5  from the reversed side. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     To put the present invention into context a packaging container is shown in the perspective view of  FIG. 1 . This is a type of packaging container which may utilize an cap according to the present invention. It should be noted that an inventive cap, inventive neck, etc may be used in combination with other packaging containers too. Returning to the packaging container of  FIG. 1 , it is composed of three constructional parts. A sleeve  150  is attached to a shoulder/neck portion  130 , and a cap  100  is arranged on the neck. It is a typical example of a Tetra Top® container, which is a well known carton bottle concept from the present applicant. The shoulder/neck portion  130  is moulded in one piece directly onto the sleeve  150 , after which a cap  100  is screwed onto the neck. The sleeve  150  is formed from a packaging laminate of standard design, i.e. a paper core with surrounding laminate layers also well known in prior art. 
       FIGS. 1 and 2  illustrates a cap and a neck respectively according to a first embodiment of the present invention. Several constructional features are similar to what has already been disclosed in the patent application PCT/EP2012/072868, which was filed yet not published at the time of filing of the present application. In particular, for details regarding the membrane portion  202  of the neck, and how it cooperates with the upper rim of the spout when resealing, reference is made directly to corresponding disclosure of PCT/EP2012/072868. 
     The cap  100  as shown in  FIG. 2  comprises a disc-shaped top portion  102 . The top-portion may be flat, or have another shape, such as the one shown in  FIG. 2 , i.e. have a central depression over a majority of the surface. In the embodiment of  FIG. 2  the top portion displays rotational symmetry, which is often the case. 
     A sidewall portion  104  depends from the top portion  102 , in what may be referred to as a generally axial direction. The exterior side of the sidewall portion  104  may be designed for e.g. appearance and for increasing gripability, yet for the purposes of the present invention it is the interior side of the sidewall portion  104  that is of concern. 
     A tamper evidence  106  is arranged a a lower end of the sidewall portion  104 . The tamper evidence  106  is preferably formed in one piece with the sidewall portion  104 , and this with the rest of the cap  100  for that matter, and is designed to break away from the sidewall portion  104  as the cap  100  is removed for the first time. For this reason there is a weakened area defining the interface between the sidewall portion  104  and the tamper evidence  106 . The weakened area, indicated by a dotted line in  FIG. 2  may be arranged during moulding of the cap  100 , or during post-moulding processing, e.g. by slitting the cap such that the interface consists of a finite number of material bridges and/or an area with material of smaller thickness in a radial direction. Such techniques are well known in literature, and with the purpose of being brief on details not relevant in isolation we will leave it to that. 
     Several tamper tabs  108  extends from a portion of the tamper evidence  106 , in the present embodiment from an end portion remote from the top portion  102 . The tamper tabs  108  are likewise formed in one piece with the tamper evidence  106  and comprises a free end and and opposite end being hingedly supported by the tamper evidence  106 . The tamper tabs  108  have two main purposes. Firstly, they should prevent the tamper evidence from rotating relative to the container neck as the cap  100  is unscrewed from the neck, and secondly they should prevent the remaining tamper evidence from being pulled off the neck in an axial direction. There are numerous tamper-tab designs available, and the one disclosed in the present embodiment is to be considered a standard solution. The skilled person could select one of several such standard solutions without departing from the scope of the present disclosure. The function of the tamper tabs  108  relies on cooperating elements of the neck, which will be discussed later, referring to  FIG. 3 . In the present embodiment there are a discrete number of tamper tabs  108  distributed around the circumference of the tamper evidence  106 . Turning in the direction of the top portion and on the interior side of the sidewall portion  106 , internal threads  110  are arranged. There may be several sets of threads, i.e. several separate threads forming a thread assembly, such as e.g. three main threads starting from different locations of the lower perimeter of the interior of the sidewall  104 , suggestively evenly distributed and running in parallel up the interior of the sidewall  104 . These main threads may be segmented, such that the thread is absent during part of its path. Whatever design the thread has, it is designed to cooperate with an exterior thread  210  of the neck  200  (see  FIG. 3 ). 
     Following the threads  110  cutting elements  112  are arranged. Specific features of these form a central part of one aspect of the present invention and they will be described later in reference to  FIGS. 5 and 6 . The purpose of the cutting elements or knives  112  is to penetrate a section of the neck  200 , below a membrane portion  202  thereof, and to separate that membrane portion  202  from the rest of the neck  200 . After that step, the cutting elements  112  serve the purpose of securing the membrane portion  202  in an axial position between the cutting elements  112  and the interior of the top portion  102 . This will reduce the amount of litter generated, yet the technical reason is that the membrane portion  202  serves an important purpose when resealing the closure. There are a number of cutting elements  112  distributed around the perimeter of the sidewall portion  104 . In the present embodiment there are five. The number of cutting elements  112  will depend on several factors, yet one important factor is the rising of the threads  110 / 210 . The cutting action is effected when unscrewing the cap  100 , and the cutting elements  112  will follow the rotational motion of the cap  100  as well as the axial movement thereof, all relative to the neck  200 . This implies that the cutting action, or “removal action” to be more general, have to be finalized within a certain turning angle since otherwise the axial movement will move the cutting element  112  out of reach from the area to be cut. So, the steeper the rising of the threads, the more cutting elements  112  are needed. On the other hand, each cutting element  112  will generate a torque resistance when the cap  100  is unscrewed the first time, and in order to reduce the opening torque to acceptable levels it is not wise to have too many cutting elements  112 . Hence, for the present embodiment five cutting elements  112  have been used, yet it is up to the skilled person to deduce a suitable number. 
     At about the same axial position as the cutting elements  112  stop elements  114  are arranged. In the present embodiment the stop elements are realized by stop ledges  114 , i.e. flanges extending from the top portion  102  down to a specific axial position, and a small distance radially inwards. In the present embodiment there are a total of five stop ledges  114  and they are dimension so as to allow for the membrane portion  202  to fit between them. The purpose of the stop elements is to prevent the cap  100  from being screwed to far down (i.e. in a closing direction) onto the neck  200 , and thus to prevent damage to membrane portion  202  during application of the cap  100  or when resealing the closure after initial opening. The stop elements of the cap cooperate with a counter element  214  of the neck  100 . The distance from the lowermost portion of the stop elements  114  and the lowermost portion of the tamper evidence  106  is designated I, as shown in  FIG. 2 . “Lowermost” could be read as “most remote to the top portion  100 ” and refers to a normal position of the cap when applied onto a standing container. For the tamper evidence  104  “lowermost” corresponds also to the free end. 
     There are other means for preventing the cap from rotating any further once it has reached a certain position on the neck. Examples include various stop arrangement on in the thread, may it be a physical block at the end of the threads  210  of the neck which the threads cannot override, or a change in rising of the threads of the neck preventing further rotation of the cap. There are more options available. The solution used in the present embodiment is simple, straightforward, does not involve any other operational parts of the cap or neck, as well as being predictable, straightforward and providing a distinct stop. 
       FIG. 3  illustrates the neck  200 , parts of which have already been described. Starting from the top a membrane portion  202  is arranged. The shape and features of the membrane portion  202  are important for various functions, and these are exensively described in the patent application already cited. These features will offer the same advantages in the present context and as such they may be incorporated in preferred embodiments of the present invention, yet they are not essential for the present invention as such. The membrane portion  202  bridges to a spout portion  204  via connection portion  203 . The connection portion  212  is a circumferential portion of reduced material thickness, which is analoguous to a weakening line. The cutting elements  112  will separate the membrane portion  202  from the spout portion  204  in the connection portion  212 . 
     In the initial position, before unscrewing the cap  100  the first time, the cutting elements  112  are positioned at an axial distance from the area to be cut, and it is of importance that the tamper evidence  106  breaks away from the cap  100  before the cutting action of the cutting elements is initiated. 
     Next to the connection portion  212 , on the side of the spout, the area which is to be the rim of the spout is located, which in turn connects to the area of the spout portion  204  where the exteriour threads  210  are located. As for the interior threads  110  of the cap the threads  210  may be an assemble of several threads. Between the area of the threads and the rim the counter element  214  is located. The counter element  214  is basically a circumferential ledge with a contact surface extending in a generally radial direction. The stop element  114  of the cap  100  is sized to abut the counter element  214  as the cap  100  is screwed onto the neck  200 . The element following the threads  210  is a stop lug  208 . The stop lug  208  (there are several such stop lugs arranged distributed along the circumference of the neck) extends radially from the neck and is designed to cooperated with the tamper tabs  108  of the cap  100  in order to prevent the tamper evidence  106  from rotating in relation to the neck. The stop lug  208  may be designed to efficiently engage with the tamper tab  108 , e.g. by being undercut in an opening direction such that it engages with a gripping engagement with a tamper tab  108  in an opening direction. The opposite side of the stop lug  208  may be gently slanted such that a tamper tap  108  easily slides over it when passing in a closing direction. This makes it possible to easily arrange the cap on the neck when applying it for the first time. It is often desired to break the tamper evidence  106  as soon as possible, and the highest of the frequency at which the stop lugs  208  are arranged around the circumference of the neck and the frequency at which the tamper tabs  108  are arranged around the circumference of the cap  100  will be the determining factor, at least at a first approximation. 
     After the tamper evidence  106  has been released from the cap  100  their engagement with the lowermost portion of the threads  210  will secure the tamper evidence  106  to the neck  200 . In an alternative embodiment a circumferential lock flange arranged below the threads  210  could fulfil the same purpose. 
     Below the stop lug  208  a circumferential flange  216  is arranged, acting as a transition to the shoulder portion of the container, if arranged on a container as the one depicted and described in relation to  FIG. 1 . In other embodiments the flange  216  may be used as an attachment area for attaching the neck onto a package. 
     The distance between the counter element  214  and the flange  216  is designated L, and in an embodiment where the cap  100  and the neck  200  are used in combination it is preferred that the relationship L&gt;I is fulfilled. Preferably L should be at least one or so millimeters larger than I, such as 1 mm or 2 mm, or 0.8 mm or 1.2 mm, or another distance between 1 or 2 mm. One reason is that once the tamper evidence  104  is released it will fall down by gravity in a resting position towards the flange  216 . However small, the gap of a mm or so will be readily spotted, indicated that the packaging container has been opened. 
     Though described separately, it is preferred that all portions of the neck is manufactured in one piece during a single moulding operation. 
       FIG. 4  illustrates a moment in time where the cap is being screwed onto the neck. Every constructional detail shown has already been described in relation to  FIGS. 2 and 3 , yet  FIG. 4  is believed to simplify the understanding of their cooperation. Further referring to  FIG. 4  it is worth mentioning that it is of importance that the cutting element is not allowed to pivot past an horizontal position (in the direction of the view of  FIG. 4 ), since this will hamper the function of the cutting elements  112 . A straightforward solution is to ensure that the length of the cutting element exceeds a clearance between the sidewall portion  104  and the spout portion  204 . During opening, the free end of the cutting element  112  will be locked in a vertical position by the portion of the membrane extending beyond the spout portion  204  (i.e. it will be localized at the weakening or connection portion  212 ) and as the cap is moved further in an opening direction the tip of the cutting element  112  will penetrate the connection portion  212 . After being severed from the spout the membrane portion  102  will be securely localized by the cutting elements  112 . 
     The cutting element  112  will now be described in more detail referring to  FIGS. 5 and 6 .  FIG. 5  is schematic plan view from below, i.e. showing the side of the cutting element  112  which will be directed towards the spout when in use.  FIG. 6  is a schematic plan view from above, i.e. showing the side of the cutting element which will be directed towards the membrane portion  102  when in use. 
     The cutting element  112  is hingedly attached to the interior side of the sidewall portion  104 , see dashdotted line in  FIGS. 5 and 6 . This hinged attachment may be realized by means of an area of reduced thickness of the material, such that the cutting element  112  may pivot in relation to the hinged attachment. The region  112 A is the cutting region of the cutting element  112 , and in this region the thickness of the cutting element  112  is reduced to form an cutting edge  112 A. The cutting edge  112 A may be rectilinear, as in the present embodiment. 
     The free end  112 B, remote to the hinged attachment may preferably be blunt, and may preferably be less sharp than the cutting region  112 A. The results is the benefit that the free end is not prone to damage the connection region between the membrane portion and the spout portion when it is not supposed to. This may e.g. when the cap is arranged on the spout for the first time. 
     The exact design of the remaining portion  112 C of the cutting element  112  is less important, though it should be designed to promote constructional stability of the cutting element, or at least not act detrimental to the same. 
     A key feature for one aspect of the present invention, or at least to an embodiment thereof, is shown at  112 D. The feature is an elevated section or protrusion  112 D extending from the surface of the cutting element  112 , while being formed in one piece therewith. The protusion  112 D is arranged on the side which faces away from the top portion  102  of the cap  100 . In relation to the neck  200  the protrusion  112 D is arranged on the side of the cutting element  112  facing the rim of the spout portion  204 . In a radial direction the protrusion  112 D is sized to be in contact with the membrane portion  202 , the flange portion extending radially outwards above the connection portion seen in  FIG. 3 , during most of the first application of the cap onto the neck. This is further indicated in  FIG. 4 . 
     In the present embodiment the protusion  112 D has an elongate shape extending along a downstream edge  112 C of the cutting element  112 , i.e. along an edge remote to the cutting region  112 A. The feature that the protrusion  112 D has a shape following the shape of the downstream edge  112 C is a preferred feature. It is also preferred that the edge of the protrusion  112 D facing the downstream edge  112 C is provided with a radius. The radius preferably extends over at least the portion of the edge being in contact with the membrane portion during initial application of the cap onto the neck. In this way the amount of debris generated during initial application of the cap onto the neck will be significantly reduced as compared to a situation where the protrusion has a sharp edge, or is absent from the cutting element  112 . The protrusion may also serve a similar purpose during initial opening of the closure, when the cutting element  112  may be clamped between the membrane portion and the spout portion. In such a situation the protrusion may help in reducing the amount of debris generated, or shaved off to use a pictorial terminology, from the spout. 
     The cap  100  may be applied onto the neck  200  in one of two ways; either the cap is pressed onto the neck in a pure axial motion, or the cap  100  is screwed onto the neck  200 . For the present embodiment constructional elements have been designed to allow for the second alternative, such as e.g. the design of the stop lugs  208 . In each sitation the cap is first arranged in a holder after which it is aligned with the neck, and thereafter is is positioned onto the neck by means of a rotational motion combined with an axial translation, or a pure rotational motion. Aligned with the neck may be restricted to that the cap is in line with the neck, i.e. that the neck and the cap have a common central axis corresponding to the axis of rotational symmetry for the main constructional features. This is a basic level of alignment. Further details may be that the cap is positioned at a particular distance from the neck, but more commonly a further level of alignment includes that the cap and neck has a particular angular relationship, e.g. that a thread start in the cap is aligned with a thread start on the neck in order to make the process more efficient. The cap and neck may be manufactured as an assembly and applied to a packaging container in assembled state. However, the basic invention and embodiments thereof may also be manufactured such that the neck is formed on an packaging container after which the cap is applied to the packaging container now provided with a neck portion. 
     The present invention may also relate to a manufacturing method of a cap/spout assembly and of a packaging container having such cap/spout assembly 
     In order to provide for that the cap easily can cut off the membrane of the spout the cap may be made of a harder material than the spout, e.g. the cap may be made of polypropylene and the spout may be made of high density polypthylene (HDPE). However, other plastic material suitable to be used for liquid food may be used as well, such as low density polyethylene (LDPE) and medium density polyethylene (MDPE). The skilled person realized that the present invention relates to technical features not associated to particular materials as such. Suitable manufacturing methods for both the neck and the cap resides within the field of plastic moulding. For the cap injection moulding may be used, and as an alternative injection/compression or even pure compression, and the same is true for the neck, although with an emphasis of injection/compression. 
     The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within 
     the scope of the invention, as defined by the appended patent claims. 
     Known details of opening devices of the cut-and-collect type (where a membrane portion is removed and localized by e.g. a cap) have been omitted from the description not to interfere with the description of the present invention.