TECHNICAL FIELD This invention relates to a device for delivering, data tags and, particularly, although not exclusively, to a device for delivering micro data tags for marking an item.

BACKGROUND Owners of motor vehicles or items may choose to apply data tags to mark the identification of each part of the vehicle or item. Data tags may be applied to a plurality of parts of the vehicle or item. These data tags may be a micro, tag (also known as a microdot) which are small individual tags with an identification code etched on each tag. Once these tags are applied to a vehicle or item, law enforcement agencies, insurance companies or other parties can examine the data tag applied on the vehicle or item and identify the ownership of the item or vehicle by cross referencing the identification code on the data tags.

Typically, data tags have been applied to vehicles or items by the use of spray guns. Spray guns are suitable for use in workshops or factories, but are otherwise unsuitable for enclosed spaces or non industrial environments. .

SUMMARY OF THE INVENTION

The present invention in its preferred embodiments seeks to provide devices for applying data tags by direct application to the item, avoiding the use of a pressurised spray.

In accordance with a first aspect of the present invention, there is provided a device for delivering data tags comprising:

a reservoir ^{^} storing data tags in a solution, the reservoir being in liquid communication with an applicator head, the applicator head being arranged to receive data tag solution and apply it to an item when the applicator head contacts the item. In accordance with another aspect of the invention, there is provided a device for delivering data tags comprising:

a reservoir storing data tags in a solution, wherein the reservoir is arranged to communicate with an applicator head to apply data tags when a plunger arrangement utilisable to discharge the data tag solution from the reservoir is actuated.

In an embodiment, the plunger is arranged to travel towards the applicator head, and is restricted from moving away from the applicator head.

In one form, a rotatable actuator is actuable to displace the plunger, and the actuator preferably includes a threaded member arranged to transfer pressure from the actuator to . the plunger such that the pressure displaces the plunger towards the applicator. In another form, an actuator including a button mechanism arranged to receive digital pressure from a user is actuable to displace the plunger towards the applicator head.

In practice, the data tags used in the preferred embodiments of the invention are microdots typically having a width or diameter of up to about 1mm. Particularly advantageously, the data tags used in the preferred embodiments have a thickness of only a few microns, about 6 microns in one practical example, but more conventional microdots having a greater thickness, for example around 60 microns, would be suitable for use in some embodiments where the delivery/applicator system is able to cope with microdots of that size. Advantageously, the solution is a water-based adhesive, and, preferably, is visually distinctive when exposed to light in a non-visible spectrum (U.V. light, for example).

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a front view of a data tag in accordance with one embodiment of the present invention;

Figure 2A is a front perspective view of a data tag delivery device in accordance with one embodiment of the present invention;

Figure 2B is a front view of the data tag delivery device of Figure 2A;

Figure 3 is an exploded view of the data tag delivery device of Figures 2 A and 2B;

Figure 4 is a longitudinal section of the data tag delivery device of Figures 2 A, 2B and 3;

Figure 4A is a longitudinal section of an associated cover; Figure 5 A is a front perspective view of a data tag delivery device in accordance with another embodiment of the invention;

Figure 5B is a front view of the data tag delivery device of Figure 5 A; Figure 6 is an exploded view of the data tag delivery device of Figures 5A and 5B;

Figure 7 is a longitudinal section of the data tag delivery device of Figures 5 A, 5B and 6; Figure 7A is a longitudinal section of an associated cover;

Figure 7B is a longitudinal section of an embodiment of the plunger arrangement of the data tag delivery device of Figures 5 A, 5B, 6 and 7;

Figures 7C and 7D are transverse sections of certain components of the plunger arrangement of Figure 7B;

Figures 7E to 7G show successive stages in the operation of an actuator of the plunger arrangement of Figure 7B; Figure 8A is a side view of a data tag delivery device in accordance with yet another embodiment of the invention;

Figure 8B is an exploded view, partly in section, of the data tag delivery device of Figure 8A; .

Figure 9A is a view of the applicator portion of a modified form of the embodiment of Figures 8 A and 8B; and Figure 9B is a schematic sectional view corresponding to Figure 9A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to Figure 1, an embodiment of a data tag 100 is shown. In this embodiment, the data tag 100 is a planar sheet cut into a hexagon shape. The data tag 100 has a unique code 102 etched onto the surface of the tag 100. This code may be observed by a user and recorded for storage or referencing purposes.

The data tag 100 may be dimensioned in microscopic sizes of approximately 0.3 to 1mm in width (w) and of only several microtis in thickness, 6 microns in one practical example. In this size, the tag 100 is barely visible to the naked eye and generally, will require careful examination by a user before the tags can be observed. However, a magnifying device such as a magnifying glass, portable magnifiers/microscope or electronic magnifiers can be used to examine the tag 100 to identify the identification code 102 on the surface of the tag.

The data tag 100 may be engaged to a surface of an item to be marked by the use of solution. The solution used will depend on the type and uses of the item to which the tag is applied. For example, where the item is a vehicle part, the solution may be an adhesive suitable for exposure to road dirt, heat and water. For indoor items, different solution may be used to engage the tags 100 to the surface of the item. In use, the data tag 100 may be provided to a user in a set which has a multiplicity of tags (hundreds or thousands of tags). Each set of data tags may have the same identification code 102 or share a set of identification codes. Once a user is in possession of the set of data tags, the user can proceed to apply the tags to a surface of an item by the use of solution to bond the tags to the surface.

In use, the user may apply some tags of the set to an item or the whole set to different parts of a larger article thus resulting in a large number of tags being bonded to the surface. A large number of tags provides an added advantage in that the task of removing the tags by an unauthorized party may be made inefficient or impossible, and thus discouraging theft s

or black market trading of the item.

The data tags 100 may be of a different shape to that shown. While tags of a hexagon shape offer advantages in being relatively easy to distinguish on a surface, however alternative shapes such as, but not limited to, circular, semi-circular, rectangular, square, or diamond also possible.

The data tag 100 may have a hologram on its surface. The hologram may be etched onto the tag to a holographic image to the user. The holographic image may be a brand or trademark, and therefore provides an additional identification means and/or marketing opportunity for the manufacturer or distributor of the tags.

With reference to Figure 2A and 2B, there is shown a embodiment of a device 200 for delivering such data tags comprising a reservoir 202 storing data tags in a solution, wherein the reservoir 202 is arranged to communicate with an applicator head 204 to apply data tags when a plunger arrangement 206 arranged to discharge the data tag solution from the reservoir 202 is actuated.

In this embodiment, the reservoir 202 is defined by a cylindrical wall and components of the plunger arrangement 206 at one end. Opposite to the plunger arrangement 206 is an opening 209, which in this embodiment is engaged to the applicator head 204 to permit the flow of the contents of the reservoir 202 to the exterior of the device 200. In this example, the applicator head 204 includes an applicator 220 which may be in the form of a brush to assist the user in evenly distributing the data tag solution flowing from the reservoir 202 and discharged by the applicator head 204 onto a surface.

The reservoir 202 contains a mixture of a set of data tags 100 immersed in a solution. The solution may be a water based adhesive arranged to permit the flow of the data tags from the reservoir to the exterior of the device during use whilst also bonding the data tags to a surface to which the data tags and the solution is applied. When the adhesive is of a high viscosity and density, only a small amount of solution may flow out of the opening 209 by gravity. In that case, the rate of flow of the solution through the opening can be increased by actuation of the plunger arrangement 206 which includes a plunger and an actuator arranged to push the solution through _s the opening 209 when pressure is applied on the actuator. The plunger arrangement 206 is described in detail with reference to Figures 3 and 4 and in another embodiment with reference to Figures 6, 7, 7 A and 7B.

Although embodiments of the device will subsequently be described in which the flow of solution from the reservoir is principally a gravity flow possibly assisted by squeezing the wall of the reservoir, the embodiments featuring a plunger arrangement are advantageous in that a more viscous and dense adhesive may be used within the device to provide a stronger bond between the data tags and a surface. Accordingly, these embodiments may thereby increase the range of applications concerning the distribution of data tags onto an item. By using a plunger arrangement 206, the generally more viscous and dense adhesive may be discharged with the immersed data tags from the device and applied to a surface without the requirements of gravity to assist the flow of the solution from the reservoir 202 and the head 209. As such, these embodiments may be more effective in situations where the device for applying data tags must be held upside down by a user.

In some embodiments a solid weighted member, such as a ball bearing, may be disposed into the reservoir with the mixture of data tags and solution to aid in the mixing of the tags 100 with the solution in the reservoir 202 to ensure that the tags are substantially immersed in the solution. The weighted member may have a volume of no more than 3 to 10% of the reservoir. As the weighted member is solid and is substantially denser then the data tags and the solution, the member can move within the reservoir to mix the data tags and the solution when the reservoir 202 is shaken.

As shown in Figure 2 A, the device has a cover 212 which is arranged to cover the head 204 when the device is not in use. In one example, the cover 212 is arranged to prevent the solution and the tags within the reservoir 202 from inadvertently flowing out of the device, whilst also preventing the solution from drying out. The cover 212 may be constructed _f from a resilient material to snap fit itself to the head 204. In other examples, the cover 212 may have a screw thread for engagement to the head 204.

With reference to Figures 3 and 4, the plunger arrangement 206 comprises a plunger 302, a threaded member 304, a ratchet member 306, an annular ring 307, a drive shaft 308 and a rotatable actuator 310.

The plunger arrangement 206 is arranged to transform rotational pressure exerted by a user , on the rotatable actuator 310 into a linear pressure on the plunger 302 such that the plunger 302 pushes the solution within the reservoir 202 to discharge the solution through the applicator head 204. In this example, the actuator 310 is arranged to rotate the ratchet member 306, which rotates the threaded member 304 around an annular ring 307 fixed to walls of the reservoir 202 and the drive shaft 308. Once the threaded member 304 is rotated about the ring 307, the threaded member 304 will travel in a linear motion and as such, the plunger 302 is pushed forward towards the applicator head 204. The resulting displacement of the plunger 302 pushes the data tag solution within the reservoir 202 out of the head 204 and onto the applicator 220 for application on a surface.

Preferably, the ratchet member 306 controls the rotational movement of the actuator such that each rotation of the actuator 310 is conducted in discrete steps. This is achieved by a plurality of resilient detents 306A arranged to interact with the teeth 31 OA of the actuator to create a pawl and gear arrangement which gently resist the rotation of the actuator to each step of the teeth 31 OA of the actuator.

In this embodiment, the teeth 31 OA and the detents 306 A are shaped such that the actuator can only be rotated in one direction to push the solution through the applicator head 204. This is because the teeth 31 OA are saw tooth shaped to create a lock between the resilient detents 306 A and the teeth 31 OA if the actuator is rotated in an opposite direction in a similar fashion to a pawl and gear arrangement. By use of the ratchet member 306, the actuator 310 cannot be reversed to retract the plunger 302 towards the actuator 310. This embodiment is advantageous in that the plunger 302 cannot be returned to an initial position by pulling the plunger 302 back towards the actuator 310. By preventing the plunger 302 from moving towards the actuator 310, air cannot be drawn back into the reservoir 202 inadvertently by a user wishing to withdraw the plunger 302, as drawing air into the reserve 202 would create a negative pressure. As the adhesive may dry when exposed to air, this arrangement will increase the life of the unused solution stored within the device.

With reference to Figures 5A to 7, there is illustrated a device 500 for delivering data tags comprising: a reservoir 502 storing data tags in a solution, wherein the reservoir 502 is arranged to communicate with an applicator head 504 to apply data tags when a plunger arrangement 506 arranged to discharge the data tag solution from the reservoir 502 is actuated.

In this embodiment, the device 500 has a reservoir 502 which is defined by a cylindrical wall and components of the plunger arrangement 506 at one end. Opposite the plunger arrangement 506 is an opening 509, which in this embodiment is engaged to the applicator head 504 to permit the flow of the contents of the reservoir 502 to the exterior of the device 500. In this example, the head 504 includes an applicator 520 which may be in the form of a brush to assist a user to distribute the data tag solution flowing from the reservoir 502 evenly on a surface.

The reservoir 502 contains a' mixture of a set of data tags 100 immersed in a solution. The solution may be a water based adhesive arranged to permit the flow of the data tags 100 from the reservoir 502 to the exterior of the device 500 during use whilst also bonding the data tags to a surface to which the data tags and the solution is applied onto. When, the adhesive is of a high viscosity and density such that only a small amount of solution may flow out of the opening 509 under normal gravity, the rate of flow of the solution through the opening may be increased by actuation of the plunger arrangement 506 which includes a plunger and an actuator arranged to push the solution through the opening 509 when pressure is applied on the actuator. The plunger arrangement 506 is described in detail with reference to Figures 6, 7, 7B, 7C and 7D.

A solid weighted member, such as a ball bearing, may be provided in the reservoir with the mixture of data tags and solution to aid in the mixing of the tags 100 with the solution in the reservoir 502 such that the tags are substantially evenly dispersed throughout the solution. The weighted member may have a volume of no more than 3 to 10% of the reservoir. As the weighted member is solid and is substantially denser then the data tags and the solution, the member can move within the reservoir to mix the data tags and the solution when the reservoir 502 is shaken.

As shown in Figure 5 A, the device has a cover 512 which is arranged to cover the head 504 when the device is not in use. In one example, the cover 512 is arranged to prevent the solution and the tags within the reservoir 502 to inadvertently flow out of the device, whilst also preventing the solution from drying out. The cover 512 may be constructed from a resilient material to snap fit to the head 504. In other examples, the cover 512 may have a screw thread for engagement to the head 504.

With reference to Figures 6, 7, 7B, 7C and 7D, the plunger arrangement 506 comprises a plunger 602, a threaded member 604, a ratchet member 606, a resilient spring 606A, an annular ring 607, a drive gear 608 and an actuator 610 which in this example includes a resilient push button mechanism 61 OA.

With reference to Figures 6, 7E and' 7 , the plunger arrangement 606 is arranged to transform the linear pushing motion of the actuator 610 by a user into a controlled rotational pressure, followed by transferring this rotational pressure into a linear pressure on the plunger 602. This linear pressure results in the plunger 602 being displaced to push the solution within the reservoir 502 for discharge thereof through the applicator head 504. In this example, the actuator 610, actuated by a user pressing on the push button mechanism 61 OA (702), is arranged to push the drive gear 608 towards the ratchet member 606 (704), which, due to the interaction of the teeth of the drive gear 608 and the ratchet member 606 rotates the ratchet member 606 to rotate the threaded member 604 around an annular ring 607 fixed to walls of the reservoir 502 (706). Once the threaded member 604 is rotated about the ring 607, the plunger 602 is pushed forward towards the applicator head 504 and in the process pushes the data tag solution within the reservoir 502 out of the head 504 and onto the applicator 520 for application to a surface or item. Once the linear pressure from a user is released from the actuator 610, a spring member 606 A resiliently returns the push button mechanism 61 OA, drive gear 608 and ratchet 606 to the initial position to allow a user to press the push button mechanism repeatedly to displace the plunger.

Preferably, a ratchet member 606 controls the rotational movement of the actuator such that each rotation of the actuator 610 can be conducted in discrete steps. This is achieved by a plurality of detents 606B arranged to interact with the teeth 608A of the drive gear 608 to gently resist the rotation of the actuator to each step of the teeth 608A of the actuator. ,

In this embodiment, the teeth 608A and the detents 606B are shaped such that the drive gear 608 can only be rotated in one direction to push the solution through the applicator head 504 in a manner similar to a pawl and gear arrangement. This is because the teeth 608A are saw tooth shaped and create a lock between the resilient detents 606B and the teeth 608A if the drive gear 608 is rotated in an opposite direction. By use of the ratchet member 606, the actuator 61 OA cannot reverse the drive gear 608 to retract the plunger 602 towards the actuator 610 and therefore, on pressing of the push button mechanism 61 OA, the plunger 602 will only push the solution out of the reservoir 502 and not retract the plunger 602 towards the actuator 61 OA.

This embodiment is advantageous in that the plunger 502 cannot be returned to the initial position by pulling , the plunger 502 back towards the actuator 610. By restricting the plunger 502 from moving towards the actuator 610, air is not drawn back into the reservoir 502. This minimises exposure of the adhesive to air. This arrangement will increase the life of the unused solution stored within a partially used device.

In practical embodiments, the mouth 214, 514 of the head 204, 504 will be sized to permit the solution and the data tags 100 to flow through the mouth 214, 514 in use. Where the data tags 100 are approximately 1 mm in width, the mouth 214, 514 may be sized to approximately 1.5 to 2 mm to permit the flow of the data tags 100 and solution through the mouth 214, 514 and onto a surface. Where the data tags are approximately 0.3 mm in width, the mouth 214, 514 is approximately 0.5 to 1 mm to permit the flow of the tags with the solution to a surface.

The device 200, 500 may be manufactured by firstl forming a reservoir 202, 502 by defining the cylindrical walls and attaching a plunger arrangement 206, 506 to the end of the reservoir 202, 502. Once the reservoir 202, 502 is defined, it can be filled with a mixture of solution and a set of data tags 100. A mixing member, which may be a small weighted rod or ball arranged to assist the mixture of the solution with the data tags 100 during use may also be added to the reservoir.

Once the reservoir is filled with the solution, data tag and the optional mixing member, an applicator head 204, 504 may be attached to the reservoir 202, 502. This is followed by the engagement of the cap 212, 512 to the head 204, 504.

The device may then be appropriately labelled with the identification code of each of the data tags 100. Once labelled, a user can then record the identification code for future identification purposes. During use, a user can hold the device and proceed to mark a surface. The user may gently shake the device such that the mixing member will assist in the mixing of the data tags 100 within the solution. Once the user wishes to deliver the data tags to a surface, the user can apply pressure to the actuator 310, 610 to push the plunger 306, 606 to discharge the solution stored within the reservoir 202, 502. The applicator 220, 520 will act to distribute a thin layer of data tags and adhesives over a surface. The data tags 100 are released with the solution onto the surface in a uniform manner. Once the data tags 100 are delivered to the surface, the solution is allowed to air dry and thereby bonding the data tags onto the surface.

In alternative embodiments, the reservoir 202, 502 may be defined by a rectangular or triangular prism wherein the side walls and end wall are arranged to define a prism to store the data tags 100 and the solution in which the tags are immersed. In other embodiments, the device may be shaped for more ergonomic grasping by a user's hand.

In the embodiments described thus far, the data tags 100 are able to be applied when the device 200, 500 is held against the direction of gravity. This is particularly useful in situations where a user must apply the data tags 100 on a surface directly above the user, as the user may actuate the plunger arrangement 206, 506 to discharge the solution without the assistance of gravity.

It will be understood that the devices described enable data tags 100 to be applied to a surface of an item without the use of spray guns which may not be suitable for operation in enclosed or domestic areas. The devices allow a user to apply data tags to an item in many environments, including those not suitable for operation of spray guns, and require minimal effort or training on the part of the user.

With reference to Figures 8A, 8B and 8C, there is shown a embodiment of an applicator device 800 in which the plunger arrangement of the previous embodiments is omitted whereby the flow of solution is primarily a gravity flow, possibly aided by manual squeezing pressure applied by the user to the body of the device. The device is therefore of simpler construction than that of the previous embodiments. The device 800 comprises a reservoir 802 storing data tags in a solution, the reservoir being in liquid communication with an applicator head, which is arranged to receive data tag solution and apply it to an item when the applicator head contacts the item.

The reservoir 802 which is defined by a cylindrical wall 806 and an end wall 808. Opposite to the end wall 808 is an opening 809, which is engaged to a head 804 arranged to permit the flow of the contents of the reservoir 802 to the exterior of the device.

The reservoir 802 contains a mixture of a set of data tags 100 immersed in a solution. The solution may be a water based adhesive arranged to permit the flow of the data tags 100 from the .reservoir to the exterior of the device during use whilst also bonding the data tags to a surface to which the data tags and the solution is applied onto. Preferably, a weighted member is disposed into the reservoir with the mixture of data tags and solution to aid in the mixing of the tags 100 with the solution in the reservoir such that the tags are substantially immersed in the solution. The weighted member may be a metallic solid rod or bearing having volume of no more than 3 to 10% of the reservoir. As the weighted member is solid and is substantially denser then the data tags and the solution, the member can move within the reservoir to mix the data tags and the solution when the reservoir is shaken. „

The head 804 has a cover 812 which is arranged to cover the head 804 when the device is not in use. In one example, the cover 812 is arranged to prevent the solution and the tags within the reservoir to inadvertently flow out of the device, whilst also preventing the solution from drying out. The cover 812 may be constructed from a resilient material to snap fit itself to the head 804. In other examples, the cover 812 may have a screw thread for engagement to the head 804. The head 804 tapers towards one end of the device distal to the reservoir to define a delivery point. At the delivery point, there is a mouth 814 arranged to allow the mixture of solution and the tags 100 within the reservoir 802 to flow from the head 804 through the mouth 814 to the exterior of the device. In this example, the mouth has a tongue 902, which is resiliently retracted into the head when pressure is applied to the tongue 902. The structure providing the resilient mounting for the tongue 902 will be described below. The tongue 902 is dimensioned to substantially close the mouth 814 from releasing the contents within the reservoir 802 when the tongue is not retracted within the head 810. This arrangement allows the user to control the flow of the mixture from the reservoir 802 to the surface of an item. Preferably the head 804 is attached to the reservoir 802 by a screw threaded connection.

The tongue 902 is connected to a ring 904 which engages the opening of the reservoir 802. The ring 904 has an aperture 906 to permit the flow of the contents within the reservoir 802 to the head 804. The tongue 902 is supported by a spring 908 which is engaged to the ring 904 whereby to provide resilient support for the tongue 902 such that the tongue may be retracted into the head during use.

The mouth 814 of the head and the tongue 902 are sized to permit the solution and the data tags 100 to flow through the mouth 814 in use. Where the data tags 100 are approximately 1 mm in width, the mouth 814 is sized to approximately 1.5 to 2 mm to permit the flow of the data tags 100 and solution through the mouth 814 and onto a surface. Where the data tags are approximately 0.3 mm in width, the mouth 814 is approximately 0.5 to 1 mm to permit the flow of the tags with the solution to a surface.

The mouth and the ball bearing are sufficiently sized to permit the flow of the data tags 100 via the ball bearing. In one preferred embodiment, the mouth is dimensioned to fit a ball bearing of at least 5 mm in diameter to permit the flow of data tags of 1 mm in diameter. Other sizes of the ball bearing are possible depending on the size of the data tags, the surface of which the data tags will likely be applied to, and the requirements of the user.

The device 800 may be manufactured by firstly forming a reservoir 802 by defining the cylindrical wall 806 and the end wall 808 through unitary construction. Once the reservoir 802 is defined, it can be filled with a mixture of solution and a set of data tags 100. The mixing member, if required may also be added to the reservoir at this stage. Once the reservoir is filled with the solution, data tag and the optional mixing member, the ring 904 assembled with the spring 908 and the tongue 902 may be engaged to the opening of the reservoir 802. This is followed by the engagement of the head 804 to the reservoir such that the mouth of the head is effectively sealed by the resiliently retractable tongue 902.

The device may then be appropriately labelled with the identification code of each of the data tags 100. Once labelled, a user can then record the identification code for future identification purposes.

During use, a user can grasp the device and proceed to mark the surface. The user may gently shake the device such that the mixing member will assist in the mixing of the data tags 100 within the solution. Once the user wishes to deliver the data tags to a surface, the user can contact the surface with the device such that the tongue 902 is retracted into the head 804. Once the tongue 902 is retracted into the head 804, the solution and the data tags will proceed to flow through from the reservoir 802, into the head 804 and out of the mouth 814 of the device to the surface of an item. The data tags 100 are released with the solution onto the surface in a uniform manner. Once the data tags 100 are delivered to the surface, the solution is allowed to air dry and thereby bonding the data tags onto the surface.

In a modification, the ring 904 has a valve which is arranged to control the flow of the data tag solution from the reservoir 802 to the head 804. The valve is actuated by the tongue 902 such that when the tongue 902 is retracted it opens the valve to permit the flow of the data tag solution from the reservoir to the head. When the tongue 902 is returned to a non- retracted position by the spring 908, the valve is closed to restrict the flow of the data tag solution from the reservoir to the head.

With reference to Figures 9A and 9B, an alternative embodiment of the device is shown. In this embodiment, the head 804 has a roller ball arrangement at the mouth 814 to control the flow of the data tags 100 and solution 110 from the reservoir and onto a surface. In particular, the mouth 814 is engaged with a ball bearing 922 which is arranged to rotate within the mouth 814. By rotating, the ball bearing 922 can deliver the data tags 100 and solution 110 from the reservoir 802 and onto a surface.

I alternative embodiments, the reservoir may be defined by a rectangular or triangular prism wherein the side walls and end wall are arranged to define a prism to store the data tags 100 and the solution in which the tags are immersed. In other embodiments, the device may be shaped for more ergonomic grasping by a user's hand.

In the embodiments described in which the plunger arrangement of the earlier embodiments is omitted, the cylindrical wall of the reservoir may have some flexibility to enable the user; when grasping the device, to gently squeeze the reservoir to assist in discharging the solution. This may be required depending on the viscosity of the solution.

The data tags applied by means of the embodiments described are, effectively, microdots. Although conventional microdots have a width or diameter of up to about 1mm, their thickness is usually around 60 microns, the data tags (microdots) particularly preferred have a thickness of only a few microns as discussed earlier, and these tags are suitable for use in all of the embodiments described. The thinness of those preferred tags is particularly advantageous in that they are virtually undetectable to the touch when applied to the surface of the, article to be marked. By the incorporation of a trace element in the solution whereby it is responsive to U.V. light, it then becomes more readily detectable by the use of appropriate equipment as may be possessed by law enforcement authorities. It is to be noted that while conventional microdots could not, due to their relative thickness, be used in the embodiments of Figures 5 to 9 as the applicator systems of those embodiments would be unsuitable, they could be used in the embodiment of Figures 2 to 4.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.