FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to a tamper-evident closure and particularly to a closure with two or more parts which separate in an opening event and then indicates the closure has been opened at least once. 
       BACKGROUND OF THE INVENTION 
       [0002]    In many cases it is desirable for a closure to provide visible evidence that it has been opened at least once. Many different systems have been proposed for tamper-evidence. One of the most common systems is to ensure that upon first opening the closure separates into two or more parts which are not re-formed upon closing. 
         [0003]    One of the main considerations when designing a tamper-evident closure is the prevention of overcoming the tamper-evidence by reforming the closure parts. This is particularly important for products which are subject to counterfeiting, such as in the wines and spirits industry. 
         [0004]    It is known, for example, to provide a closure with a generally plain crown and a tubular skirt with a line of weakening which divides the closure into an upper top cap and a lower tamper-evident break band. Upon first opening of the closure the cap and the band are physically separated and upon re-application of the top cap the band remains broken away from the cap. However, it has been found that counterfeiters can re-form such closures by connecting the cap back to the break band using, for example, nail varnish. Such a re-formed cap may be indistinguishable from an untampered closure. 
         [0005]    The present invention seeks to address the problems with known tamper-evident closures. 
       SUMMARY OF THE INVENTION 
       [0006]    According to a first aspect there is provided a tamper-evident closure for a container, the closure comprising a shell having a break line along which it is separable, in which the shell further comprises a distortable portion which is distorted upon first opening, the distortable portion being spaced from and separate to the break line. 
         [0007]    According to a further aspect there is provided a tamper-evident closure for a container, the closure comprising a shell having a break line along which it is separable, the shell comprising a line of weakness along which it is separated upon first opening of the closure, the shell further comprising a deformable region which is distinct from the break line and is inevitably deformed by axial stretching of the shell during first opening, the closure comprising means for limiting the extent of the axial stretching of the deformable region. 
         [0008]    According to another aspect there is provided a tamper-evident closure for a container, the closure including a body having two or more parts which are separated upon first opening along a line of weakness, the opening event causes one or more parts of the body to be distorted, the distortion occurs in a region of the body discrete from the line of weakness. 
         [0009]    According to a further aspect there is provided a closure for a container, the closure comprising: an outer shell separable into a first shell portion and a second shell portion, the first shell portion and/or the second shell portion comprising a distortable portion; and an inner part in engagement with the first shell portion, wherein in an opening event, the first shell portion is movable relative to the inner part from an unactivated first position to an activated second position in which there is a predetermined axial movement of the first shell part with respect to the inner part, the opening event causing deformation of the distortable portion, the distortion being limited by the predetermined axial movement of the first shell part with respect to the inner part, the first shell portion and the inner part being arranged to become irreversibly locked in the activated second position so that the first shell portion and the inner part cannot be moved back to the unactivated first position. 
         [0010]    The tamper-evidence of the present invention therefore does not rely entirely upon separation of closure shell, but also deformation/distortion of a different part/region so that it is more clear an opening event has occurred and so that returning the closure to its original, unopened state is rendered considerably more difficult. 
         [0011]    The distortion may be produced by various methods including stretching, twisting pulling, squashing and tearing. The distortion may affect the integrity of the part and/or its properties including shape, thickness, colour and markings 
         [0012]    The or each body part may be distorted before, during or after breakage and/or separation of the shell. In other words, the distortion may be completed prior to, as part of, or following physical separation. 
         [0013]    The distortion may be caused by axial separation of two or more parts (which may, for example be shell sections) for example as the parts are pulled away from each other during opening by having one of the parts captive on a container and the other part moveable. 
         [0014]    The distorted part may be adapted to remain on the container in use. Alternatively, the distorted part may be adapted to be removable with undistorted part/s remaining on the container. 
         [0015]    The body may include one or more lines of weakness. 
         [0016]    The body may comprise a top cap with a tamper evident band at its free end. For example, the body may comprise a shell with a top plate and a depending side wall, with the tamper evident band formed at the free end of the side wall. The free end of such a side wall may be secured to a container neck for example by a tuck-in and/or a tuck-under to secure that part of the body to a container neck. 
         [0017]    In embodiments where a tamper-evident band is provided it may be the tamper-evident band which is distorted. Alternatively, or additionally, the top cap of such an arrangement may be distorted. 
         [0018]    The distortable region may include a notch line or the like along which distortion occurs in use. The notch line may involve a partial or complete cut through the material of the body. In such cases the arrangement of the distortion line must be such that distortion occurs prior to separation of the parts. This could be done, for example, by selecting an appropriate strength for frangible bridges holding the parts together at a line of weakness. 
         [0019]    The body may be formed from any suitable material, for example metal and or plastics material. In some embodiments the closure is of the form of a roll-on pilfer-proof type which is typically formed from aluminium. 
         [0020]    Different aspects of the invention may be used separately or together. 
         [0021]    Further particular and preferred aspects of the present invention are set out in the accompanying independent and dependent claims. Features of the dependent claims may be combined with the features of the independent claims as appropriate, and in combination other than those explicitly set out in the claims. 
         [0022]    According to a further aspect of the present invention there is provided a container in combination with a closure as described herein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]    The present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: 
           [0024]      FIG. 1  is a side view of a closure formed according to an embodiment of the present invention shown in a sealed, unopened position; 
           [0025]      FIGS. 2A to 2D  show the opening sequence of the closure of  FIG. 1 ; 
           [0026]      FIG. 3  is a side view of a closure formed according to an alternative embodiment and shown in an unopened condition; 
           [0027]      FIGS. 3A to 3D  show the opening sequence of the closure of  FIG. 3 ; 
           [0028]      FIG. 4  is a section of the closure of  FIG. 3 ; and 
           [0029]      FIGS. 4A to 4D  show the opening sequence in sectional form of the closure of  FIG. 4  i.e. corresponding to  FIGS. 3A to 3D  respectively. 
       
    
    
     DESCRIPTION 
       [0030]    Referring first to  FIG. 1  there is shown a tamper-evident closure generally indicated  10  attached to a container (in this embodiment a bottle) neck  15 . 
         [0031]    The closure  10  comprises a generally circular top plate  20  having a generally cylindrical side wall  25  depending from its periphery. 
         [0032]    The side wall  25  includes a knurled zone  30  adjacent the top plate  20 . Adjacent the knurled zone  30  a screw thread profile  35  is provided and corresponds to screw thread formations formed on the neck  15 ; the profile  35  is formed by rolling the side wall  25  on to the neck  15 . 
         [0033]    Towards the open end of the side wall  25  a line of weakness  40  is formed by a plurality of frangible bridges  45 . On one side the line  40  defines a tamper-evident band  50  the free end of which is turned under a bead (not shown) on the neck  15  at a tuck under  52 . At the other side of the line  40  a top cap  55  is defined. 
         [0034]    Referring now to  FIGS. 2A to 2D  the closure  10  is shown during opening. 
         [0035]    The top cap  55  is turned and the screw thread profile  35  begins to rise up the screw thread formations  36  on the neck (see  FIG. 3 ). The band  50  is prevented from lifting by the tuck under  52 . 
         [0036]    The band  50  has a distortion zone  70  formed within it. More specifically, the frangible bridges  45  are not directly connected to the distortion zone  70  but rather a solid intermediate band  80  connects the bridges  45  to the distortion zone  70 . 
         [0037]    As shown best in  FIG. 2B , the distortion zone  70  comprises a hidden notch line with alternating upper and lower slots  85   b,    90   b  which are defined by respective alternating upper and lower fixed points  85   a,    90   a,  with the upper fixed points  85   a  connected to the solid band  80  and the lower fixed points  90   a  connected to the tuck under  52 . 
         [0038]    Upon opening, the distortion band  70  is pulled and stretched into a zig-zag shape shown in  FIG. 2B . The bridges  45  then break and the top cap  55  is removed and the distorted band  50  drops down, as shown in  FIG. 2C . The band  50  remains on the glass finish. Upon re-application of the top cap  55  the zig-zag distorted area  70  remains as visual evidence the closure has been opened at least once, as shown in  FIG. 2D , with a gap G between the top cap  55  and the drop band  50  and the distorted band itself. 
         [0039]    Referring now to  FIGS. 3 and 4  there is shown a closure  110  formed according to an alternative embodiment. 
         [0040]    The closure  110  is quite similar to the closure  10 , with a top cap  155  and drop band  50  part forming an outer shell (in this embodiment formed from metal). The band  50  is longer and includes an insulating bead  154  below the break line  140  and above the distortion zone  170 . 
         [0041]    The insulating bead is rolled into the shell so as to be spaced from an undercut  117  formed on the neck finish  115 . The finish  115  also includes a step  118  below the undercut  117 . 
         [0042]    Referring now also to  FIGS. 3A to 3D  and  4 A to  4 D, when the closure  110  is first opened the tuck under  152  prevents any axial movement of the band. The band  150  is stretched against the tuck under  152  until the insulating bead  154  engages the undercut  117 . Accordingly, the notched distortion zone  170  is stretched to the position shown in  FIGS. 3B and 4B . 
         [0043]    Continued turning of the top cap  155  now causes the main bridges  145  to break. The top cap  155  can now be screwed off and the band  150  drops down, as shown in  FIGS. 3C and 4C , until the bead  154  rests on the step  118 . 
         [0044]    When the top cap  155  is replaced there is a gap G between the cap  155  and the band  150 , as shown on  FIGS. 3D and 4D . 
         [0045]    In other embodiments (not shown) a further gap generating mechanism may be included, for example as described in WO2005/049443. 
         [0046]    Although illustrative embodiments of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is understood that the invention is not limited to the precise embodiments shown and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents.
A tamper-evident closure for a container, the closure comprising a shell having a break line along which it is separable, in which the shell further comprises a distortable portion, which is distorted upon first opening, the distortable portion being spaced from and separate to the break line.