GB2353935A

GB2353935A - Colour-changing drinking straw

Info

Publication number: GB2353935A
Application number: GB0015342A
Authority: GB
Inventors: William James Stephen Barker
Original assignee: B&H Liquid Crystal Devices Ltd
Current assignee: B&H Liquid Crystal Devices Ltd
Priority date: 1999-06-22
Filing date: 2000-06-22
Publication date: 2001-03-14
Anticipated expiration: 2020-06-22
Also published as: GB0015342D0; GB2353935B

Abstract

A drinking straw has a plastics tubular body which changes colour when subjected to a particular physical condition; the condition may not be apparent in normal operating conditions. Only parts of the straw may change colour. There may be at least two different colour-changing materials which change colour in response to different physical conditions, or there may be a single colour-changing material. The colour-changing materials may be angularly spaced apart to provide discreet regions e.g. stripes or elongate regions. The colour-changing material in one part of the body may comprise particles in a plastics material. The physical condition may be different temperatures or temperature ranges, or it may be a type of electromagnetic radiation such as ultraviolet radiation. The straw may be used as a game mechanic for a lottery-type game and the colour-change may indicate a winning straw.

Description

2353935 Drinking Straw This invention relates to a drinking straw and in

particular to a drinking straw which is able at least partially to change colour. The invention has particular, although not necessarily exclusive, application to so-called "security straws" which can be used to reveal whether a user has won a prize when the straw is subjected to certain physical conditions.

Drinking straws which change colour in use are already known. For example US-A-3957202 discloses a novelty drinking straw formed from an elongate tubular member having a layer of liquid crystalline material placed thereon. The layer of liquid crystalline material is covered by an added transparent membrane and changes colour when the temperature of a liquid drawn through the straw varies from the ambient temperature.

The present invention seeks to provide- a novel drinking straw which changes its appearance urfder different physical conditions.

According to one aspect of the present invention there is provided a drinking straw having a tubular plastics body which changes colour when subjected to a particular physical condition.

The invention covers a drinking straw with a tubular plastics body made from a single colour-changing plastics material which may form the entire tubular plastics body but which may be combined with at least one other plastics material which does not change colour to provide discrete regions, e.g. stripes, of the different plastics materials.

Preferably, however, the straw is designed to change different colours when subjected to different physical conditions. For example, the straw may be formed, e.g. extruded or otherwise moulded, from a single plastics material containing particles of at least different first 2 and second colour-changing materials. Preferably, however, the straw is formed, e.g. extruded or otherwise moulded, from at least first and second plastics materials arranged in discrete regions, e.g. stripes, which change colour when subjected to different physical conditions, e.g. over different temperature ranges. For example the first plastics material (or the first colour-changing material) can be designed to colour change when used with a cooled drink and the second plastics material (or the second colour-changing material) can be designed to colour change outside normal ambient and cold drink temperatures. Alternatively, the first and/or second plastics material (first and/or second colour-changing materials) can be designed to colour change when subjected to specific types of electromagnetic radiation, e.g. ultra violet or other wavelength electromagnetic radiation. Alternatively, the first plastics material (or first colour-changing material) can be designed to colour change over a specific temperature range and the second plastics material (or second colour- changing material) can be designed to colour change when subjected to a specific type of electromagneic radiation, e.g. ultra violet radiation.

A drinking straw according to the invention has particular application as a game mechanic giving users the possibility of winning prizes, e.g. monetary prizes, in a manner similar to a lottery scratch card. A user would recognise the straw as being a "winning" straw by the straw changing colour in use, e.g. when the user drinks a cold drink. The "winning" straw would be verified at a pay out station by being subjected to a physical condition outside the normal operating conditions of the straw, e.g. by being subjected to an elevated temperature or to a different form of electromagnetic radiation, such as ultra violet radiation. The straw would be verified if it further changed colour when subjected to such physical conditions outside the normal operating conditions of the straw. Alternatively, the colour- changing feature of the straw may only be used for "win" verification (e. g. when subjected to 3 - a physical condition outside the normal operating conditions of the straw) In this case, means other than colour change could be used to indicate to a user that the straw was a winning straw.

According to another aspect of the present invention, there is provided an extruded drinking straw 'having angularly spaced apart elongate portions formed from different plastics materials at least one of which changes colour when subjected to a particular physical condition.

A specific embodiment of the invention will now be described, by way of example only, in the following non limitative example.

EXAMPLE

Two different extrudable plastics resins were 15 prepared. The first extrudable plastics resin comprised a polypropylene plastics resin incorporating a first colourchanging material, e.g. a microencapsulated thermochromic composition, and a dye. The... second extrudable plastics resin comprised a polypropylene plastics material incorporating a second colour-changing material, e.g. a microencapsulated thermochromic composition, and a dye. Each colour-changing material exhibits a reversible change in its chemical structure when passing from one to the other side of a "clearing point" 'or clearing temperature.

Typically the colour-changing material has specific colour below its clearing point but loses its colour, and becomes clear, when its temperature passes through the clearing point so that the colour of the dye is apparent. The "clearing points" of the two colour-changing materials are chosen so that in use of the finish product the clearing points are at different temperatures or temperature ranges. Such colour-changing thermochromic compositions are typically, but not exclusively, of the electron donor/acceptor type.

The first extrudable plastics resin is typically selected to change colour when the finished straw is used normally. For instance, the first colour-changing material could be selected to change colour when used with a cold 5 drink or a partly frozen drink. In this case the first colour-changing material could be selected to change colour when cooled to a specific temperature, e.g. within the temperature ranges of from 20C to 200C or from -101C to 100C, respectively.

The second colour-changing material is typically chosen to change colour at temperatures outside temperatures encountered in normal use. For example the second colourchanging material could be selected to change colour at hotter-temperatures. Thus for example the second colourchanging material could be one colour, e.g. red, at room temperature, another colour, e.g. yellow, at a first elevated temperature, such as around 450 C, and a different colour, e.g. white or clear, at a higher temperature, such as around 600 C.

A plastics tubular extrudate was then created by extruding the heated first 'and second colour-changing materials under pressure. The first and second materials were injected at two, four or more points to create a striped extrudate which was subsequently cut to form striped straws of the desired length.

The straws produced have stripes at least one of which will change colour at a temperature not obvious to the user outside the usual ambient or cold drink temperatures.

Instead of changing colour with temperature, the second colour-changing resin can be selected to change colour when subjected to different physical conditions, e.g. when subjected to ultra violet radiation or the electromagnetic radiation outside the ultra violet range.

The stripes in the straw may not normally be visible. For example in normal usage a straw may appear white but, when used with a cold drink, the first colour-changing material may change to red so that the straw then appears to be striped red and white. in this case the second colour changing material may be selected to change to a different colour, e.g. yellow when subjected to non-standard usage conditions, e.g. at high temperature or when subjected to U.V. radiation.

The colour-changing materials are preferably chosen to exhibit reversible colour change.

The aim of the invention is to create a drinking straw from safe, nonhazardous materials, the straws having a security feature provided by a colour-changing property not apparent in normal operating conditions of the straw. In other words the straw is intended to change colour when subjected to conditions such as an elevated temperature (i.e. above cold drink and ambient temperatiAr es) or when subjected to specific types of electromagnetic' radiation, e.g. ultra violet radiation. Th. e physical condition causing the colour changing phenomenon should preferably be selected so that a user would by unlikely to be aware of it and which would be difficult for the user to replicate. The straw can thus be used as a "win" indicating and verifying straw if the straw is used as a game mechanic for a lottery-type game. The or each colour-changing material could be prepared from a mix of standard colours, e.g. 3% blue, 1% red and 96% natural resin, resulting in a purple stripe, to make copying that much more difficult.

It is also possible to design straws according to the invention which change colour when used with hot drinks as opposed to cold drinks.

in addition to forming the stripes in a single extrusion, the stripes could be added after extrusion of the main part of the straw tube, e.g. through a printing/striping head.

It is possible to incorporate two or more colourchanging materials in a base material forming a stripe or stripes in the straw. In this case, the colour-changing materials would be selected to change colour when subjected to different physical conditions, e.g. different temperature ranges. It is also possible to provide a straw according to the invention having only a single plastics material which changes colour when subjected to a specific physical condition. For example, a striped straw could be formed from stripes of a first plastics material which do not change colour and stripes of a second plastics material which can change colour.

Claims

- 7 CLAIMS

1. A drinking straw having a tubular plastics body which changes colour when subjected to a particular physical condition.

2. A straw according to claim 1, characterised in that said particular physical condition is not apparent in normal operating conditions of the straw.

3. A straw according to claim 1 or 2, characterised in that said tubular plastics body is constructed so that only a part or parts thereof change colour when subjected to said particular physical condition.

4. A straw according to claim 1, 2 or 3, characterised in that said tubular plastics body comprises at least two different colour changing materials one of which change colour when subjected to said particular physical condition and the other of which chang es colour when subjected to a different physical condition.

5. A straw according to claim 1 or 2, characterised in that said tubular plastics body consists of a single colour-changing plastics material.

6. A straw according to claim 1, 2, 3 or 4, characterised in that said tubular plastics body comprises at least one colour-changing plastics material spaced apart from at least one other plastics material which does not change colour to provide discrete regions, e.g. stripes, of different plastics materials.

7. A straw according to claim 1, 2, 3 or 4, characterised in that said tubular plastics body comprises a base plastics material containing particles of a first colour-changing material which changes colour when.subjected to said particular physical condition and at least one second colour-changing materials which changes colour when 8 subjected to at least one different physical condition to said particular physical condition.

8. A straw according to claim 1, 2, 3 or 4, characterised in that said tubular plastics body comprises at least first and second plastics materials arranged in discrete regions, e.g. stripes, the first plastics material changing colour when subjected to said particular physical condition and said second plastics material changing colour when subjected to at least one different physical condition to said particular physical condition.

9. A straw according to claim 7 or 8, characterised in that said different physical conditions are different temperatures or temperature ranges.

10. A straw according to claim 1, 2, 3 or 4, characterised in that said tubular plastics body has angularly spaced apart first and second elongate portions formed from first and second plastics materials, respectively.

11. An extruded drinking straw having a tubular plastics body with angularly spaced apart elongate portions at least one of which changes colour when subjected to a particular physical condition. .

12. A straw according to claim 11, characterised in that said particular physical condition is not apparent in normal operating conditions of the straw.

13. A drinking straw substantially as herein described with reference to the Example.