[0001] This invention relates to container closures and is more particularly concerned with
tamper-evident closures.
[0002] According to the present invention there is provided a container closure comprising
a top, a dependent skirt and a tamper-evident ring connected to the bottom edge of
the skirt by a plurality of circumferentially spaced frangible bridges or along a
circumferentially extending line of weakening, the radially-outer faces of the ring
and the skirt of the closure having applied thereto a coherent pattern, legend or
representation which is in colour constrast with other parts of the skirt and ring
and which becomes visually disrupted or distorted on fracture of the frangible bridges
or line of weakening during removal of the closure from a container.
[0003] The pattern, legend or representation may extend continuously along the band, and
at least the adjoining portion of the skirt. A legend where employed may be in the
form of words and/or names and/or digits, for example the name of the product in the
container, and/or the manufacturer of the product and/or the batch coding of the products,
or a "sell by" date, or a direct message such as "Do not accept if this band is broken".
Thus a pattern of lines or a legend would be disrupted by any circumferential displacement
of the ring relative to the skirt and would render words distorted or illegible so
as to call immediate attention to the fact that the closure had been tampered with,
although the tamper-evident ring might otherwise appear to the eye to be still intact
and connected to the skirt.
[0004] Examples of the types of pattern which may be applied to the ring and the radially-outer
surface of the part of the skirt immediately adjoining the band are fine, dotted rectilinear
oblique lines, and heavy dotted rectilinear oblique blocks, but there are numerous
possible alternative patterns.
[0005] In production of the container closures described in the foregoing, the radially
outer surface of the band and of at least the immediately adjoining portion of the
skirt of the moulded closure may be treated to improve their capacity to form a good
bond with the ink or paint to be employed. In one such process, the said surfaces
are subjected to a corona discharge, which serves also to neutralize or remove from
the closure any of the release agent employed to facilitate removal of the moulding
from the mould. Paint or ink is then applied to the surfaces in the desired pattern,
legend or representation and is air-dried or cured by heating or infra-red or ultra-violet
treatment according to the type of colouring substance used. Where wording is to be
employed on the said surfaces, pulse-jet apparatus may be used.
[0006] It will be understood that the type of mechanism by which the tamper-evident ring
is induced to become at least locally separated from the skirt on removal of the closure
is irrelevant to the invention.
[0007] One embodiment of the invention is shown in the accompanying diagrammatic drawings
in which:
Figure 1 shows a closure according to the invention applied to a container,
Figure 2 shows the commencement of separation of the tamper-evident from the closure
as the closure is removed from the container, and
Figure 3 shows the closure after removal from the container.
[0008] Referring to the drawings, there is shown a closure 10 of the tamper-evident type
secured on the neck of a bottle 11. The closure comprises a top 12, a depending skirt
13 and a tamper-evident ring 14 connected to the bottom end of the skirt by a line
of weakening 15 incorporating a series of circumferentially spaced frangible bridges
16 and a wide bridge 17. The top, skirt and ring 14 are moulded in one piece from
plastics material but the closure may incorporate a separate sealing gasket made from
the same or a different plastics material. From one end of the wide bridge 17 an axial
line of weakening 18 extends to the bottom edge of the ring 14. The radially inner
surface of the ring 14 has a series of inward projections 19. The neck of the bottle
is formed with an external screw-thread by which the closure is engaged on the bottle,
and below the screw-thread has an annular security band 20. When the closure is screwed
onto the bottle, the projections on the ring 14 pass over the security band, but when
the closure is removed the projections 19 engage the bottom edge of the security band
20 and resist upward movement of the tamper-evident ring, causing the frangible bridges
to fracture in the well known manner. Numerous forms of projection equivalent to projections
19 have been proposed and the particular form is irrelevant to this invention.
[0009] As shown in Figure 1, a representation 21 of some notes of music is printed on the
ring 14 and on the adjoining portion of the skirt 13, for example removing any release
agent remaining on the closure by means of a corona discharge technique and subsequently
applying paint or ink as described previously. The representation 21 forms a coherent
whole such that any distortion of the parts thereof on the ring 14 or any displacement
of the parts thereof on the ring 14 relative to the parts thereof on the skirt 13
is readily apparent to the eye.
[0010] As shown in Figure 2, during removal of the closure from the bottle the ring 14 breaks
along the line of weakening 15 and commences to separate from the skirt by breaking
the bridges 16. When removal of the closure from the bottle is complete, the ring
14 remains attached to the skirt by the wide bridge 17. However, during removal of
the closure, some permanent distortion of the material of the ring takes place, so
that even if the closure is replaced on the bottle with the tamper-evident ring 14
apparently in its former position, secured for example by glue, the representation
17 is no longer coherent by reason of the distortion and it is therefore readily apparent
to the eye that the closure has been removed and replaced.
[0011] The invention is applicable also to metal closures having a tamper-evident ring,
including closures where the screw-thread and the tamper-evident ring are rolled on
to the closure in the well-known manner.
[0012] In all cases it is preferable that there should be one or more wide bridges interconnecting
the skirt and the tamper-evident ring so as to produce the maximum distortion of the
ring, with at least local permanent stretching or other mis-shaping of the ring, during
removal of the closure.
1. A container closure comprising a top, a dependent skirt and a tamper-evident ring
connected to the bottom edge of the skirt by a plurality of circumferentially spaced
frangible bridges or along a circumferentially extending line of weakening, the radially-outer
faces of the ring and the skirt of the closure having applied thereto a coherent pattern,
legend or representation which is in colour constrast with other parts of the skirt
and ring and which becomes visually disrupted or distorted on fracture of the frangible
bridges or line of weakening during removal of the closure from a container.
2. A closure as claimed in claim 1, wherein a line of weakening is present between
the tamper-evident ring and the skirt and has a circumferential interruption whereby
the ring remains connected to the skirt along the interruption of the line of weakening
on removal of the closure from a container.
3. A closure as claimed in claim 1, wherein the connection between the skirt and the
tamper-evident ring includes one or more wide bridges in a line of frangible bridges.
