WO2007020418A1

WO2007020418A1 - Toy article incorporating photochromic ink and /or dyes and a light source

Info

Publication number: WO2007020418A1
Application number: PCT/GB2006/003031
Authority: WO
Inventors: Fred Cahill
Original assignee: Carterbench Product Development Ltd
Priority date: 2005-08-15
Filing date: 2006-08-15
Publication date: 2007-02-22
Also published as: GB0801701D0; GB2443120A; GB2443120B

Abstract

The invention to which this application relates is to the provision of a toy which incorporates, in at least a portion thereof, photochromic inks or dyes and the toy further incorporates means to allow the change in condition of the photochromic inks or dyes to be achieved in a controlled manner via a light source. The relative movement between the light source and the portion can be controlled by the user. The invention also incorporates means to control the light which is emitted so as to provide a safe and effective light illumination source.

Description

Toy Article Incorporating Photochromic Ink and /or dyes and a Light Source

The invention to which this application relates is to the provision of articles such as toys and games which incorporate, in at least a portion thereof, inks or dyes which are reactive to certain types of light when exposed thereto and which are hereinafter referred to as photochromic inks or dyes. Typically the toys further incorporate means to allow the change in condition of the photochromic inks or dyes to be achieved in a controlled manner which is entertaining to a child playing with the same.

The use of photochromic inks or dyes is well known and indeed, there are many patents which relate to specific photochromic ink and dye compounds. The principle behind photochromic ink is that in a first condition, the ink or dye has a first colour or shade and, when exposed to a particular type of light source, the colour or shade of the ink or dye changes. The inks or dyes can be provided to be reactive to particular types of light source so that the change in condition will only occur when the particular light source to which the same is susceptible, is exposed to the ink or dye.

An aim of the present invention is to provide apparatus and a method for the utilisation of photochromic inks or dyes in toys in a particular manner which allows the toys to be particularly attractive to children, allows the effects which are created to be unexpected, particularly to children and thereby provide a commercially attractive product. A further aim is to provide a means whereby the illumination of the light source is controlled effectively to allow unnecessary and/or prolonged illumination of the same and hence provide a toy which is safe to use. In a first aspect of the invention, there is provided a toy, said toy having a surface, at least a portion of the surface having applied thereto or formed with, at least one photochromic ink or dye, said toy further including a light source, the activation of which, and/or direction of which, can be controlled by the user of the toy, wherein said light source has at least one light component when illuminated which, when directed by the user towards the said portion of the surface, causes a change in condition of the photochromic ink or dye which is visible to the user.

In one embodiment the change in condition of the photochromic ink or dye is a change in colour. In one example the said portion, prior to the application of the light source, has an appearance which is similar to the surface adjacent to the said portion and when the light source is directed towards said portion, the change in condition renders the said portion visibly differentiated from the adjacent surface.

In an alternative embodiment, the said portion has a first colour which is different to the adjacent surface, prior to the light source being applied thereto and, once the light source is applied thereto, the change in condition causes the portion to change to a further colour which is different from the adjacent surface or, alternatively, to change to a colour which is the same as that of the adjacent surface.

In one embodiment, a plurality of light sources are provided and at least one of the light sources has a light component which when the same is switched on, and directed at the photochromic ink or dye, causes a change in condition of the same.

In one embodiment, although a plurality of light sources are provided, only one of the light sources causes the change in condition of the photochromic ink or dye and the other light source(s) is /are provided as a guidance means for the user.

In one embodiment the effect of the light transforming the surface is enhanced by the addition of sounds activated when the light source is turned on. These sounds can in one instance be used to create the illusion that the light source is a form of spray can or airbrush.

In one embodiment, the movement of the light source with respect to the surface, is controlled by the user via a mechanical guide means . In one embodiment, the mechanical guide means is a pantograph arrangement which can be controlled by the user or, alternatively, a stencil is provided to be followed by the user with the light source either by moving the light source directly with respect to the stencil or by using the stencil to restrict the movement of mechanical guide means to which the light source is connected, such as a pantograph.

In one embodiment, the light source is incorporated within a holder such as a stylus or pen which can be held by the user to control the movement of the light source with respect to the portion on which the photochromic ink or dye is provided.

In one embodiment, the toy or plaything is a writing or drawing toy.

In one embodiment the portion which includes the photochromic ink or dye is provided as a flat surface onto which the pen or stencil can be pressed and an electrical switch is provided to be activated when the pen or stencil is pressed onto the surface, so that the light source is then switched on. Thereafter, movement of the pen or stencil in contact with the surface, causes continued illumination of the light source and the change in condition of the photochromic ink or dye on said surface over which the light source is moved.

In one embodiment of the toy, the light source is mounted behind a portion surface which is presented to the user and the user can control movement of the light source via a joystick which operates a pantograph mechanism connected to the light source.

In one embodiment the toy may further include a top surface which is at least partially transparent to allow the user to view the changes in colour created by the light source to the flat drawing surface, but is preferably at least partially opaque to the colour frequency of the light source. In this manner the contrast between the original colour of the plastic and the light activated colour can be increased as ambient light of the activating light frequency is prevented from hitting the drawing surface. Furthermore the transmission of the light into the eye of the user is reduced.

In one embodiment there is provided over the surface which includes the photochromic ink or dye, a layer which can be etched or clouded, and which disguises the appearance of the portion which has the photochromic ink or dye.

In one embodiment, the toy is a plush or model character, said character having a surface coated with or incorporating photochromic ink or dye on at least a portion thereof, and said user is provided with a pen or stylus including a light source such that when the light source is directed towards the external surface portion including the said ink or dye, the same changes condition. In one embodiment the user can cause a change in condition of the ink or dye at said portion so as to allow patterns, writing or other drawing shapes to be formed on the external surface of the character by the change in condition of the photochromic ink or dye cause by the movement of the pen or stylus.

In this embodiment the colour change may additionally change the colour of particular characteristics of the toy such as the hair, makeup, freckles, tattoos, or bumps, scratches and bruises.

As an alternative, the plush or model character can contain the light source internally and facing outwardly, and on switching the light source on, the photochromic portion of the plush or model character changes colour.

In one embodiment, the photochromic ink or dye is incorporated within the material used to form the external surface of the character or alternatively can be printed onto the external surface.

In a further embodiment of the invention, the toy includes an article, said article positionable with respect to a light source, said light source operable and directed towards a surface of the article incorporating photochromic ink or dye such that prolonged exposure to the light source, causes a gradual change in condition of at least certain of the features of the external surface of the article to change the condition of the same.

In a further embodiment, the article is movable with respect to the fixed light source or alternatively, the article is fixed and the light source is movable with respect to the same such that relative movement between the article and the light source, causes the light source to be applied to the article in a particular path, and said path causes a visible pattern to be created on the article due to the change in condition of the photochromic ink or dye which lies along said path. In one embodiment, the light source which is provided is a relatively focused pen light source. In one embodiment, the holder which includes the light source, can include focusing means, typically in the form of optical lens, which allows the user selection of the area of the surface onto which the light source is applied at any given position and with the light source at a given distance from said surface.

As an alternative to focusing means, the pen, stencil or other holding means for the light source can be selectively changed so as to change the area of application of the light source.

In one embodiment, the activation of the light source and directing of the light source onto a surface on which the photochromic inks or dyes are provided, is caused by the user interaction with another part of the toy or plaything such that the change in condition which is created by the activation of the light source to change condition of the photochromic ink or dye, provides an unexpected change on the toy, to the user.

In a further embodiment, the application of heat, typically from a relatively gentle heat source, can be used on the photochromic ink or dye to act as a means of rapidly reversing the colour trans formation which has occurred. The heat source can be generated in many ways including creating a resistive circuit and using direct friction against the photochromic surface.

In a further aspect of the invention, there is provided a toy, said toy having a surface, at least a portion of the surface having applied thereto, or formed with, at least one photochromic ink or dye, said toy further including a light source which can be selectively directed onto the said at least one photochromic ink or dye to cause a change in condition of the same and wherein said light source is pulsed.

Preferably, the length of illumination in each pulse is greater than the required length of time of exposure of the light source to the said photochromic ink or dye to commence a change of condition of the same such that one pulse of light is sufficient to at least commence the change in condition.

Preferably, the time of non-illumination is relatively short such that to an onlooker, the appearance is of a substantially continuous light source.

However, the pulsing of the light source is controlled to ensure that the length of any given pulse of illumination is sufficiently small so as to prevent or minimise the risk of damage to the eye if looking directly at the said light source.

In one embodiment, the control means for pulsing of the light source can be provided as an integral part of the light source itself or alternatively, a separate control system can be provided in connection with the power supply to the said light source so as to provide a pulsed power supply to light source and hence provide the pulsed illumination.

It should therefore be appreciated that the provision of a pulsed light source can be incorporated with any form of light source which is suitable to cause the change in condition in the dyes or ink and therefore can be provided to cause the pulsed illumination of an LED, an infrared light source, an ultraviolet light source, a laser light source, or any other suitable light source. In one embodiment there is provided a switch device which allows the user activation of the light source.

In one embodiment, the switch device is provided of a form which is activated by bringing a light source carrier into contact with or within a predefined range of a portion on which the photochromic ink or dye is provided. In one embodiment, either of the light source holder or the portion has a magnet or reed switch mounted thereon and the other of the light source holder and portion can be formed of magnetic material such that when the light source holder and portion are brought together, within the predefined range, activation of the light source occurs as a result of activation of the switch.

In one embodiment, both the light source and portion incorporate magnets such that only when said magnets are brought together does activation of the switch occur.

The magnets which are provided may be discrete individual magnets at specific locations or alternatively, the portion may comprise an entire sheet of magnetic material.

When the switch is activated, the light source may be illuminated for a predetermined period of time. Alternatively, the light source is active for only the duration of the light source carrier being within the predefined range of the base.

In one embodiment the ink or dye which is applied or indeed the portion of the toy on which the ink or dye is located, is conductive, or is doped with sufficient carbon to change the resistance which is registered by the application of a conductive part of a light source holder onto the portion. As a result, the light source can only be illuminated when the light source is activated when the light source holder touches the conductive portion and therefore can cause the change in condition of the photochrome ink or dye.

In one embodiment, the light source holder includes two contact points, free of any cable connection, and the light source is switched on when both contact points are in contact with the conductive surface. Alternatively, a cable leads from the light source which connects the light source holder with the base and activates the light source when the portion is contacted by the contact point of the light source carrier to complete the circuit.

In one embodiment, the conductive surface is positioned under the active colour change portion of the toy, typically a base, which includes the photochromic ink or dye.

In one embodiment the light source holder is provided with a tilt switch or sensor positioned such that the tilt switch or sensor is only activated when the holder is in a particular orientation.

In one embodiment the orientation required is when facing towards the portion of the toy on which the colour change is to be provided.

This therefore means that as soon as the light source is tilted away from the portion and potentially to face the user or an onlooker, the tilt switch or sensor changes condition to be inactive and the light source cannot be illuminated.

In one embodiment the light source holder is connected via a mechanical linkage to the toy such that the light source is movable across a plane substantially parallel to the plane of the portion or a surface on which the photochromic ink or dyes are provided. This arrangement prevents the light source from being raised any significant distance from the surface.

In a further embodiment, the light source carrier is carried by a mechanical linkage behind the said portion with respect to the user and a magnet is provided on the opposing side of said portion the movement of which causes movement of the light source carrier which follows the movement of the magnet.

In one embodiment the portion incorporating the photochromic ink or dye includes a layer, a first side of said layer provided to be viewable to a user of the toy and on the opposing side of said layer, there is provided a light source and holder, said light source and holder selectively movable via direct or indirect movement means controlled by the user and wherein any ultraviolet emissions from the light source are filtered as they pass through the said layer and to which the said light source is directed, thereby filtering out UV light prior to the same reaching the user.

In one embodiment, the light source which is emitted incorporates the blue light portion of the visible spectrum rather than ultraviolet light.

In one embodiment, the light source is activated via a trigger switch, said trigger switch biased to an off condition such that in order to move the trigger switch and hence light source to an on condition, a pressure is required to be applied against the biasing means.

In one embodiment, the biasing means is at least one spring mounted so as to push the trigger switch to an off position. Specific embodiments of the invention will now be described with reference to the accompanying drawings, wherein: -

Figure 1 illustrates a first embodiment of a drawing toy in accordance with the invention;

Figure 2 illustrates a second embodiment of a drawing toy in accordance with the invention;

Figure 3 illustrates a further embodiment of the invention in which an article condition is changed as a result of the illumination of a light source;

Figure 4a and b illustrate a yet further embodiment of the invention;

Figure 5 illustrates a further embodiment of the invention with regard to model characters;

Figure 6 illustrates a yet further embodiment of the invention in which the remote activation of the light source is achieved; and

Figures 7a-b illustrate two possible switch arrangements which may be utilised..

Referring firstly to Figure I ₃ there is illustrated a first embodiment of a writing or drawing toy 2 in accordance with the invention. In this case, the writing or drawing toy 2 includes a portion 4 having a surface on which the graphical interaction occurs in accordance with the invention. The portion is mounted on a base 6.

In this embodiment the base includes a control area 8 with a joystick 10 which can be gripped by a user to be movable with respect to the control area 8. The joystick 10 is mounted and connected to a pantograph mechanical lever arrangement provided within the base 6 and under the portion 4. The free end of the mechanical arrangement includes a holder and a light source 12 which is distinguishable through the portion 4 to the onlooker. In one embodiment, the extent or degree of visibility of the light source 12 to the user, may only be such as to provide a visual indication of the location of the same with respect to the portion 4 and provide guidance to the user. The same or a further light source at the same location as the first, can be provided which includes a light component such as ultraviolet light, which causes a change in condition of the photochromic ink or dye which is selectively incorporated within, or applied to, the portion 4.

In whichever case the light source used will incorporate a light component which is known to cause the change in condition of the particular photochromic inks or dyes which have been used. For example, one required light component may be specific UV light.

In one embodiment, a series of different colours of photochromic dyes or inks can be incorporated on the portion 4 with the same being provided in distinguishable bands or lines of different colours or shades . Alternatively, the dyes or inks can be provided in a mixed, random or marbled state within the material forming the portion. In either case, when the light source with the appropriate light component is passed across the portion and, in the case of Figure 1 , behind the portion, so the photochromic ink or dye changes colour. Thus, the toy in Figure 1 has the ability to firstly, create a line drawing or area and, secondly, provide shading and different colours which are viewable. Figure 2 illustrates a further embodiment of a writing or drawing toy 2 which again includes a portion 4 on which the drawing occurs, and a base 6. In this case, there is provided a pen style light source holder 14 which is connected by cable 16 to the drawing toy base 6. In one embodiment a power supply 18 is housed within the base 6. In an alternative embodiment a power supply can be contained in the holder 14 itself. The power supply is provided to allow the illumination of a light source 20 at the free end of the holder 14 and in one embodiment, the light source can be a blue LED.

The portion 4 is impregnated with bands or areas of different colour dyes or inks that will only appear strongly when the light source 20 passes thereover under the guidance of the user who grips the holder 14. In an alternative embodiment, the surface contains only one colour of photochromic ink or dye across its entire drawing surface. In a still further embodiment multiple colours of photochromic dye or ink are mixed in the material forming the drawing portion 4 so that a generally marbled surface of colour can be revealed.

In one embodiment, the holder can also incorporate lens 22 which can be selectively positioned by the user with respect to the light source so as to alter the area of the light source applied to the portion such that, for example, in one position, the lens can cause a thin line to be created as the holder is moved across the surface and in a further position can create a thicker line such as a spray effect as the holder and light source are moved across the surface.

Preferably, a switch device is provided and in one embodiment the light source will only be illuminated when the free end is pressed down onto the portion 4 to activate an electrical switch within the holder and hence causes the supply of power to the light source 20. The provision of this feature prevents the possibility of the light source being illuminated when the pen is not directed towards the portion 4 surface and, in turn, prevents the possibility of the light source being shone into the eyes of a user, such as a child.

Also shown in this drawing is the possibility of providing stencils 24 which can be placed in a drawer 26 as shown and slidingly inserted as indicted by arrow 28 to lie under the surface 4. In this way, light will only be allowed to pass onto certain parts of the surface which are exposed by the apertures in the stencil.

Figure 3 illustrates a further embodiment of the invention in which there is provided a toy, in this case provided to depict a microwave oven. In this case, the toy has a housing 30 with a door 32 and a series of articles 34 which can be selected by the user to be placed into the housing. In this case, one of the articles 34 is shown provided in the housing and illustrated is a light source 36 which is illuminated and directed downwardly onto the article portion 38. The portion 38 has photochromic ink or dye incorporated therein and is of a type which may be of different colours and of a constitution to cause a gradual change in colour thereby giving the effect of the article, in the form of the item of foodstuff, being cooked and changing from an appearance when the same would be frozen as illustrated by the articles 34, to an appearance when the same has been cooked in a normal microwave as indicated by the articles 34'. This embodiment therefore gives the appearance of a cooking operation and can be applied to many forms of potential toy oven designs .

Figures 4a and b illustrate a yet further embodiment of the invention in which there is provided a light source 40 mounted on a holder 42 and an article in the form of a car 44. In this embodiment, an article is mounted on a turntable 46 and the turntable is pivotably moved as indicated by arrows 48, 50 via the user actuation of disc 52. In this case, the holder 42 can be fixed or alternatively, can be pivotably located about pivot points 54, 56 or alternatively may be mounted on a deformable member 58 as shown in Figure 4b so as to alter the position of the holder, and hence the light source 40, with respect to the article, as well as allowing the article 44 to be rotated. It will therefore be appreciated that by this relative movement the light source which is applied to the article external surface 45, and which surface includes portions of photochromic inks or dyes, can cause a pattern and/or shapes to be formed onto the same as the colour of the photochromic inks or dyes changes colour, typically, in this case changing from a condition whether the same is not readily visible as it is the same colour as the remainder of the external surface, to a colour which is more readily viewable as the same is exposed to the light source.

It should also be appreciated that particular patterns or shapes may be applied using the photochromic ink or dye such that when the light source is applied thereto, the shapes are already created and therefore become visible upon exposure to the light source.

Figure 5 illustrates a further arrangement whereby there are provided toy characters 60 which can be soft plush toys or vinyl shaped characters. In any case, at least the external surface of the characters can have photochromic ink or dyes applied on one or more portions by printing, or the same may be impregnated into the fabric or other material which forms the outer surface of the same. When the light source is applied thereto using the holder 62 in which the same is located so patterns, writing or shapes 64 can become visible. Furthermore, the actual colour of the surface may also change.

Figure 6 illustrates a yet further embodiment of the invention and in this case, there is provided an article 66 which has a portion 68 in which photochromic ink or dye is applied. In this case, when the article 66 is worn on the doll 70, the same is positioned close to the light source 72 within the doll in the form of a blue LED, however this light source is not viewable to the user. Furthermore, the light source is connected via hidden cable 74 to the doll's mouth 76 such that the placing of an article such as a bottle 78 or spoon 80 into the mouth 76 causes a switch at the dolls mouth to be activated which, in turn, activates light source 72 and causes light to be shone onto the portion 68 of the article worn on the doll which causes the same to change colour due to the change in condition of the polychromic ink or dye. Additionally there can be provided two light sources to separately light different portions of the diaper 66 to selectively light different coloured areas and to represent imaginary food or fluids that would have passed through the doll.

It is preferred that the light source and holder are provided with the user's safety in mind. In one arrangement the light source is illuminated in pulses with the intensity and/or duration of each pulse being sufficient so as to cause a change in condition in the photochromic ink or dye.

In addition or alternatively, a switch device can be provided which only allows operation of the light source when it is safe to do so. One form is the pressure sensitive switch in which only when pressure is applied to the free end of the holder is the switch activated and the light source illuminated. Figure 7 a — b illustrate two embodiments of switch arrangements which may be incorporated. In Figure 7a there is provided an arrangement where the light source holder 14 has a magnetic reed switch 70 at the free end thereof and the portion 4 is provided with a layer of magnetic material 72. This means that when the light source holder and portion are brought together, within a predefined range 73, activation of the light source occurs as a result of activation of the switch 70.

In an alternative embodiment shown in Figure 7b the ink or dye which is applied or indeed the portion 4 of the toy on which the ink or dye is located, is conductive. As a result this forms part of the circuit which supplies power to the light source and the light source can only be illuminated when conductive tips 74 of the holder 14 touches the conductive portion 4. In the embodiment shown in Figure 7b the light source holder includes two contact points, free of any cable connection, and the light source is switched on when both contact points are in contact with the conductive surface as the power supply circuit within the holder 14 is then completed.

In one embodiment, the conductive surface can be positioned under the active colour change portion of the toy, typically a base, which includes the photochromic ink or dye.

In the arrangement where the light source holder is connected via a mechanical linkage to the toy such that the light source is movable across a plane substantially parallel to the plane of the portion or a surface on which the photochromic ink or dyes are provided the light source is prevented from being raised any- significant distance from the surface and this therefore prevents the risk of the light being emitted elsewhere other than onto the portion to which the same is directed..

In one embodiment, the biasing means is at least one spring mounted so as to push the trigger switch to an off position

It will therefore be appreciated that the use of polychromic inks or dyes allows a full spectrum of colour change to be selected and furthermore, the change in condition, and the rate of fade after the change of condition can be selected to suit particular purposes. The photochromic inks or dyes can be provided in different layers or bands to provide specific features and furthermore, the light source, which is typically ultraviolet light, can be provided in a form and or the operation of the same is controlled so as to minimise the risk of injury to a child from the same being shone into the child's eyes, by the use of electronic switches and/or positioning of filters between the light source and the child playing with the toy.

It should also be appreciated that while the invention has been described with regard to toys, the same features can equally be applied with respect to clothing, such as footwear, articles to be worn and other items such as, for example, packs, lunch boxes or the like and the same are incorporated herein by reference.

Claims

1. A toy, said toy having a surface, at least a portion of the surface having applied thereto or formed with, at least one photochromic ink or dye, said toy further including a light source, the activation of which, and/or direction of which, can be controlled by the user of the toy, wherein said light source has at least one light component when illuminated which when directed by the user towards the said portion of the surface, causes a change in condition of the photochromic ink or dye which is visible to the user.

2. A toy according to claim 1 wherein the change in condition of the photochromic ink or dye is a change in colour.

3 A toy according to claim 2 wherein the said portion, prior to the application of the light source, has a colour which is similar to the surface adjacent to the said portion and when the light source is directed towards said portion, the change in condition renders the said portion visibly differentiated from the adjacent surface.

4. A toy according to claim 2 wherein the said portion has a first colour which is different to the adjacent surface prior to the light source being applied thereto and, once the light source is applied thereto, the change in condition causes the portion to change to a further colour which is different from the adjacent surface.

5. A toy according to claim 2 wherein the said portion has a first colour which is different to the adjacent surface, prior to the light source being applied thereto and, once the light source is applied thereto, the change in condition causes the portion to change to a colour which is similar to that of the adjacent surface.

6. A toy according to claim 1 , wherein a plurality of light sources are provided and at least one of the light sources has a light component which when the same is illuminated and directed at the photochromic ink or dye, causes a change in condition of the same.

7. A toy according to claim 6 wherein only one of the light sources causes the change in condition of the photochromic ink or dye and the other light source(s) is/are provided as a guidance means for the user.

8. A toy according to claim 1 wherein the effect of the portion is enhanced by the addition of sounds activated when the light source is turned on.

9. A toy according to claim 1 wherein the movement of the light source with respect to the surface, is controlled by the user via a mechanical guide means.

10. A toy according to claim 9 wherein the mechanical guide means is a pantograph arrangement which can be controlled by the user.

11. A toy according to claim 1 wherein a stencil is provided to be followed by the user with the light source either by moving the light source directly with respect to the stencil or by using the stencil to restrict the movement of guidance means to which the light source is connected.

12. A toy according to claim 1 wherein the light source is incorporated within a holder which can be held by the user to control the movement of the light source with respect to the portion on which the photochromic ink or dye is provided.

13. A toy according to claim 1 wherein the toy is a writing or drawing toy.

14. A toy according to claim 1 wherein the portion which includes the photochromic ink or dye is provided as a surface onto which a light source holder can be pressed and an electrical switch is provided in the holder which is operated when the holder is pressed onto the surface to switch the light source on.

15. A toy according to claim 1 wherein the light source is mounted on a side of the portion opposing the surface which is presented to the user.

16 A toy according to claim 15 wherein the user controls movement of the light source via a joystick which operates a pantograph mechanism connected to the light source.

17. A toy according to claim 16 wherein the toy includes a top surface which is at least partially transparent to allow the user to view the changes in condition created by the light source and is at least partially opaque to the colour frequency of the light source.

18. A toy according to claim 1 wherein the portion which includes the photochromic ink or dye has a layer thereover which is etched or clouded to mask the appearance of the surface which has the photochromic ink or dye.

19. A toy according to claim 1 wherein the toy is a plush or model character, having a surface coated with or incorporating photochromic ink or dye on at least a portion thereof, and a holder including a light source such that when the light source is directed towards the external surface of the said character, the user can cause a change in condition of the portion so as to allow patterns, writing or other drawing shapes to be formed on the external surface of the character.

20. A toy according to claim 19 wherein the change in condition may change the colour of particular characteristics of the toy or items mounted on the toy at that time.

21. A toy according to claim 1 wherein the toy contains the light source internally, and on switching the light source on, the photochromic portion of the toy exposed to the light changes colour.

22. A toy according to claim 1 wherein the photochromic ink or dye is incorporated within the material used to form the external surface of the toy or is printed onto the external surface.

23. A toy according to claim 1 wherein the toy includes an article positionable with respect to a light source, said light source operable and directed towards a portion of the article incorporating photochromic ink or dye such that prolonged exposure to the light source, causes a change in condition of at least certain of the features of the said at least one portion of the article.

24. A toy according to claim 1 wherein relative movement between an article on which the at least one portion of photochromic ink or dye is provided and the light source causes the light source to be applied to the article in a particular path, and said path causes a pattern to be created on the article due to the change in condition of the photochromic ink or dye which lies along said path.

25. A toy according to claim 1 wherein a holder is provided for the light source and the holder includes focusing means, which allows the user selection of the area of light which is applied from the light source at a given distance from said portion.

26. A toy according to claim 1 wherein the holder for the light source can be changed so as to change the area of application of the light source.

27. A toy according to claim 1 wherein the application of heat is used on the photochromic ink or dye to reverse the change of condition.

28. A toy according to claim 1 wherein the light source is continuously illuminated when power is supplied thereto.

29. A toy according to claim 1 wherein the light source is pulsed between illuminated and non illuminated conditions when power is supplied thereto.

30. A toy according to claim 29 wherein the length of illumination in each pulse is greater than the required length of time of exposure of the light source to the said photochromic ink or dye to commence a change of condition of the same.

31. A toy according to claim 29 wherein the time of non- illumination is such that, to an onlooker, the appearance is of a substantially continuous light source and the length of any single pulse of illumination is sufficiently small so as to prevent or minimise the risk of damage to the eye if looking directly at the said light source.

32. A toy according to claim 1 wherein the toy includes a switch device which allows the illumination of the light source when the switch is closed.

33. A toy according to claim 32 wherein the switch device is closed when a light source holder is brought into contact with or within a predefined range of the said at least one portion of photochromic ink or dye.

34. A toy according to claim 33 wherein either of the light source holder or the portion has a magnet or reed switch mounted thereon and the other of the light source holder and portion is formed of magnetic material.

35. A toy according to claim 33 wherein both the light source and base incorporate magnets such that when said magnets are brought together activation of the switch occurs.

36. A toy according to claims 32-35 wherein when the switch is activated, the light source is illuminated for a predetermined period of time.

37. A toy according to claims 32-35 wherein the light source is active for the duration of the light source carrier being within a predefined range of the base. "

38. A toy according to claim 1 wherein the photochromic ink or dye and /or portion to which the same is applied is conductive and a light source holder includes at least one conductive contact which, when in contact with the said portion allows completion of a power supply circuit to the light source and allows illumination of the light source.

39. A toy according to claim 38 wherein the conductive surface is positioned under the portion which includes the photochromic ink or dye.

40. A toy according to claim 32 wherein the light source holder is provided with a tilt switch or sensor positioned such that the tilt switch or sensor is only activated when the holder is in a particular orientation.

41. A toy according to claim 40 wherein the orientation required is when the light source is facing towards the said portion.

42. A toy according to claim 1 wherein a first side of said portion is provided to be viewable to a user and on the opposing side of said portion there is provided a light source and holder, selectively movable via direct or indirect movement means controlled by the user.

43 A toγ according to claim 42 wherein any ultraviolet element of the light source is filtered as it passes through the said portion thereby preventing the same from reaching the user.

44. A toy according to claim 1 wherein the light which is emitted incorporates the blue light portion of the visible spectrum rather than ultraviolet light.

45. A toy according to claim 1 wherein the light source is activated via a trigger switch, said trigger switch biased to an off condition such that in order to move the trigger switch and hence light source to an on condition, pressure is required to be applied against the biasing means .

46. A toy according to claim 45 wherein the biasing means is at least one spring mounted so as to bias the trigger switch to an off position.