This invention relates to an information indicating device.

It is known to provide a tamper evident sealing device comprising a membrane adapted to be located adjacent an opening of a container so that, when the container is opened, the membrane is modified, for example by being severed. The membrane may, for example, comprise shrink-sleeving extending around a lid and neck of a container, shrink-sleeving of the complete container, or a label.

A problem with such a tamper evident device is that human awareness is necessary when a membrane is modified.

It is desirable, therefore, to provide a tamper evident sealing device which is adapted to provide a signal to a machine if a membrane of the device has been modified and the device subsequently is scanned by the machine. In this manner many articles each having such a device may be scanned without each having to be examined by human intervention for tamper evidence.

It is also known to provide colour-change time/temperature sensors for indicating when perishable goods have been removed from a controlled environment for longer than a predetermined period. However operation of this system also is generally dependant on human awareness of colour change of the sensors.

It is desirable, therefore, to provide a system in which a signal is transmitted to a machine from packaging of such goods when the packaged goods are scanned by the machine subsequent to the predetermined period.

The invention is characterised in that information reproduced on a membrane which is adapted to be carried on a container and which is adapted to indicate undesirable exposure of at least a portion of the container is machine readable coded information indicative of contents of the container.

The information may be a bar code arranged such that, when the membrane is modified, for example severed, on opening of the container provided with the membrane and the bar code subsequently is scanned by scanner, a signal is generated indicative of the fact that the container has been opened.

If the bar code is reproduced on a membrane adapted to respond by colour change to a time/temperature exposure, the colour change may be arranged to cause a signal to be generated when ^• the bar code subsequently is scanned by a scanner indicating the undesirable exposure beyond a predetermined interval or beyond a predetermined temperature.

Following is a description, by way of example only and with reference to the accompanying drawings, of one method of carrying the invention into effect.

In the drawings:-

Figure 1 is an elevation of an upper portion of a container which is closed by a cap and is sealed by one embodiment of a device in accordance with the present inventionm

Figure 2 is a perspective view of a security envelope which includes another embodiment of a device in accordance with the present invention,

Figure 3 is a transverse cross section of a portion of the envelope shown in Figure 2

Figure 4 is a transverse cross section of a portion of a security envelope which includes another embodiment of a device in accordance with the present invention.

Referring now to Figure 1 of the drawings there is shown a tamper evident sealing seal 1 comprising a heat shrink sleeve 6 having a scannable bar code portion 2 printed on an outer surface thereof and the sleeve 6 extending circumferentially of a container 3 so as to bridge a neck 4 of the container 3 and a screw cap 5 located on the neck 4. The heat shrink characteristics of the sleeve 6 are such as to restrict relative movement between the sleeve 6 and the container 3 and cap 5. The sleeve 6 is provided with a plurality of spaced

parallel rows of perforations 7 extending in an axial direction of the neck 4 through an area of the sleeve 6 provided with the code 2.

When the cap 5 is unscrewed relative to the neck 4 of the container 3, the sleeve 6 is subjected to torsional forces and shears at the rows of perforations 7 thus destroying the code 2 and rendering it unscannable.

The arrangement of the spaced parallel rows of perforations 7 extending in an axial direction of the neck 4 of the container 4 ensures that, when the cap 5 is unscrewed from the neck 4, portions of the sleeve 6 between adjacent rows of perforations 7 detach from the container 3, thereby providing a clear indication that the container 3 has been opened.

It will be appreciated that the rows of perforations 7 may be arranged to extend in a circumferential direction of the neck 4 of the container 3 instead of in an axial direction thereof.

It will also be appreciated that circumferential flanges 8,9 may be•provided on the neck 4 and or the cap 5 or other means such as studs and protrusions may be provided to ensure destruction of the sleeve 6 when the cap 5 is unscrewed.

Referring now to Figure 2 of the drawings there is shown a security envelope 10 comprising a closure flap 11 adapted to be adhesively secured in a closed position to a back face 12 of the envelope 10. The flap 11 includes a pair of spaced

parallel transverse perforations 14, 15 providing a tear strip 13 which is severable from the flap 11 to open the envelope 10.

Referring now to Figure 3 of the drawings, the tear strip 13 is shown in greater detail and comprises a transparent layer 16, which is the material of the flap 11, and and adhesive layer 17 overlying an information layer 18 which, in turn overlies a substrate layer 19. The substrate layer 19 is united with the back face 12 by means of a further adhesive layer 20, which is a permanent adhesive.

The information layer 18 preferably is a bar code which is scannable from outside of the envelope 10 and is sandwiched between the substrate layer 19 and adhesive layer 17 such that it is anaerobically sealed from the atmosphere. Peeling of the transparent layer 16, to open the envelope 10 results in separation of the first layer 16 and the adhesive layer 17 to expose the information layer 18. This is achieved by ensuring that the adhesive layer 17 has less affinity to bond with the information layer 18 than the adhesive layer 20 to bond the substrate layer 19 with the back face of 12 the envelope 10. Exposure of the information layer 18 to air results in chemical or physical change and causes alteration or obliteration of the information thereby indicating that the envelope 10 has been opened.

Referring now to Figure 4 of the drawings , there is shown a security envelope similar to the envelope 10 shown in Figure 2

except that the information layer 18 disintegrates upon peeling away of the tear strip 13 - part of the layer 18 remaining bonded to the adhesive layer 17 and part remaining bonded to the substrate layer 19.

In another embodiment (not shown), the substrate layer 19 may be removed and the information layer 18 thus is sandwiched between the two adhesive layers 17 and 19.

It will be appreciated that alteration or obliteration of the information layer 18 need not be air initiated. For instance, tearing or separation of the components could result in release of a chemical which affects alteration or obliteration of the information.

The information layer 18 may comprise a magnetic coating which is destroyed when the information layer 18 is destroyed.

It will be appreciated that the membrane may be adapted to expose additional machine readable information when the membrane is modified.

It will also be appreciated that the membrane may be adapted such that, when modified, the machine readable information remains scannable but a different message is read.

Furthermore, it will be appreciated that the membrane may envelop additional machine readable information and may be arranged such that, when the membrane is modified, a substrate

carrying the additional machine readable information is exposed.

It will also be appreciated that the membrane may envelop the machine readable information and may be arranged such that, when the container is exposed beyond a predetermined period, the machine readable information is obscured from being scanned.