FIELD OF THE INVENTION The present in\ ention pertains to the field of indicator de\ ices, particularh indicator de\ices comprising transition substances coupled to textiles, and processes of manufacturing same

BACKGROUND

Use of transition substances, such as thermochromic and/ or photochromic d} es, is known in the art for manufacturing indicator de\ ices and apparel, wherein change in colour of the transition substances is used to indicate in an ambient condition

U S Patent No 6,504,161 discloses a radiation indicator de\ ice comprising a radiation sensitπ e mixture which undergoes a colour change which is \isualh recognizable when exposed to UV radiations The radiation sensitπ e mixture includes an organic halogen constituent capable of producing at least one acidic product upon exposure to ultra\iolet radiation and an indicator constituent capable of producing a change in colour in response to a change in concentration of the acidic product The radiation sensitπ e mixture has a first colour representing a relatπ eh low concentration of the acidic product and has a second colour representing a relatπ eh high concentration of the acidic product The first colour is \ isualh distinguishable from the second colour The de\ice maj also include a graphic pattern interposed amongst the radiation sensitπ e mixture, which graphic pattern has a graphic pattern colour substantialh identical to either the first colour or the second colour

U S Patent No 6,585,555 discloses a colour changing w ater to} ha\ing a porous absorbent core made from soft open cell foam, and is co\ ered with colourful graphics, at least one of which are printed with thermochromicalh sensitπ e paint or d} e

U S Patent No 4,601,588 discloses a temperature-indicating sheet which, when exposed to temperatures higher than the prescribed temperature in temperature-control for the common low -temperature preseπ ed goods, changes in colour according to the exposure temperature and time The sheet of this patent comprises a component which melts at the prescribed temperature, a substance w Inch changes in colour in contact with the component and a membrane permeable to the molten component The component is included in microcapsules which can be broken b} outer pressure at a temperature used, and in which the component and the substance are arranged at the opposite sides with respect to the membrane

U S Patent No 6,990,688 discloses use of thermochromic and/ or photochromic d} es in the manufacture of w aterproof apparel, wherein the use of thermochromic and/ or photochromic d} es are incorporated into the resin mix for fabricating the flexible sheet material

U S Patent No 5,985,381 discloses methods for increasing the camouflaging effect of an} camouflaging pattern, b} coating a photochromic material o\ er at least a portion of the camouflaging pattern

The maiorit} of the transition substances of the prior art are incorporated into the fibers used in the manufacture of the fabric In a few cases the d} eing or printing methods are used to apph the transition substances to the fabric materials With respect to textile or fabric materials d} ed or coated w ith the transition substances, there exists a problem w ith respect to the durability of such coated or d} es materials and. in particular, with respect to colour fastness, w ash fastness etc

SUMMARY OF THE INVENTION

The present im ention relates to a process of manufacturing indicator de\ ices im ohing coupling of at least one transition substance to a textile or fabric material The process of the present im ention pro\ ides indicator de\ ices with increased durability , in particular with respect to w ash fastness and/or colour fastness under \ anous conditions such as repeated w ashing, dr\ cleaning, bleaching or exposure to heat and/or light

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 illustrates an embodiment of the indicator de\ ice formed b} the process of the present im ention showing the transition and non-transition substances applied in predetermined shapes and colours, wherein the non-transition substance becomes \ isible upon colour change in the transition substance with a change in temperature from abo\ e 0 degrees C to below -15 degrees C.

Figs 2a and 2b illustrate embodiments of the indicator de\ice formed b} the process of the present im ention showing the transition and non-transition substances applied in predetermined shapes and colours, wherein the non-transition substance becomes \ isible upon colour change in the transition substance with a change in temperature from about normal bod} temperature to abo\ e 38 degrees C.

Figs. 3a and 3b illustrate embodiments of the indicator de\ ice formed b} the process of the present inv ention showing the transition and non-transition substances applied in predetermined shapes and colours, wherein the non-transition substance becomes \ isible upon colour change in the transition substance with a change in temperature from about normal bod} temperature to abo\ e 37 or 38 degrees C.

Figs. 4a and 4b illustrate embodiments of the indicator de\ ice formed b} the process of the present inv ention showing the transition and non-transition substances applied in predetermined shapes and colours, wherein the non-transition substance becomes \ isible upon colour change in the transition substance w ith a change in ultra\ iolet (UV) radiation detection from little or no UV radiation detected to a relatπ eh high degree of UV radiation detected, such as betw een 4 - 10 and hi ^L gBh ^L er on the UV index

DETAILED DESCRIPTION OF THE INVENTION

Definitions

The term "condition ^" is used to define an existing state, with reference to an entit} including but not limited to a lrung being or inanimate ob)ect Examples of existing states, include but are not limited to, temperature state, pressure state, moisture state, ultra\ iolet radiation state, or other state which ma} change or transform in an identifiable manner in response to a stimulus, as w ould be readih understood b} a w orker skilled in the art The existing state ma} also be w ith reference to the em ironment proximate to the entit} , including but not limited to the atmospheric state proximate to an entit} or state of a second entit} proximate to a first entit} The term "identifiable change ^" is used with reference to a change in a transition substance that can be detected including, but not limited to, changes that can be detected b} one or more unassisted human senses or with the assistance of instruments and the like

As used herein, the term "about ^" refers to a +/- 10% \ anation from the nominal \ alue It is to be understood that such a \ anation is alw a} s included in an} gi\ en \ alue pro\ided herein, w hether or not it is specificalh referred to

Unless defined otherwise, all technical and scientific terms used herein ha\ e the same meaning as commonh understood b} one of ordinan skill in the art to which this in\ ention belon ^l gBs ^J

Process of the Present Invention

The present in\ ention pro\ ides a process for manufacturing an indicator de\ice comprising at least one transition substance coupled to a textile or fabric material The process of the present in\ ention generalh comprises the steps of apph ing at least one transition substance to the textile follow ed b} apph ing a poh mer coating o\ er the transition substance, and curing the coated textile The transition substances used in the process of the in\ ention are configured to change in the presence of or in response to a change in the condition/state

The process of the present in\ ention ma} further comprise a step of apph ing a non- transition substance to the textile The non-transition substance can be applied before or after the application of the transition substance The non-transition substance can be applied under, o\ er and/or ad)acent the transition substance

The non-transition substance can be applied in specific colours, forms or shapes to pro\ ide further information and/or signals about the change in a condition as indicated b} the transition substance The non-transition substance can also be applied in specific colours, forms or shapes to pro\ide a reference point for comparing the degree of change and/or lntensit} of the stimulus causing the change in that condition For example, the non-transition substance can be applied in the same colour as the final colour of the transition substance to indicate the end point or the maximum le\ el of a stimulus causing the change

The non-transition substance can be applied to be \ isible subsequent to colour change in the transition substance The non-transition substance can be applied to gradualh be re\ ealed w ith the corresponding change in colour of the transition substance For example the non-transition substance can be applied under a transition substance, which masks the non-transition substance initialh and gradualh changes from a dark colour to a light colour thereb} gradualh re\ eahng the non-transition substance

The process maj further comprise the step of dn ing the non-transition substance after application

The process maj further im oh e the steps of dn ing the textile after apph ing the transition substance and/or non-transition substance and/or after apph ing the poh mer coating

The process maj further include a step of apph ing an acn he coating to the textile/fabric material before the step of apph ing the transition and/or non-transition substance in order to impart strength to the material for handling during the coupling process and to impro\ e the w ash fastness of the indicator de\ice under \ anous w ashing conditions and/or to pre\ ent fra} ing if the textile material/fabric is cut

The process maj further comprise a step of prehminan curing after apph ing the transition substance and/or poh mer coating to enhance the durability of the indicator

In one embodiment of the in\ ention, the process comprises the steps of apph ing an acn he coating to the textile, apph ing a non-transition substance to the textile, dn ing the non-transition substance, apph ing a transition substance on the textile, dn ing the transition substance, apph ing a poh mer coating to the non-transition and transition substances, and curin *g& the textile

The process of the present in\ ention can be carried out b} printing, screening or other method as w ould be readih understood b} a w orker skilled in the art Suitable printing processes include rotan printing, w here the ink is applied to the fabric using a rotan drum In other embodiments, a screen printing process machine, a roto print machine, stamping machine, or flexographic print machine ma} be used to couple the transition substance to the textile

In another embodiment of the present inv ention, the transition substance is a d} e, wherein the fabric material can be dipped into the d} e enabling the coupling thereof w ith the fabric material A w orker skilled in the art w ould readih understand a number of w a} s to couple a transition substance in the form of a d} e w ith a fabric material, w herein the selection of apparatus can depend on how much and/or where the transition substance is to be coupled w ith the fabric material

The amounts of the transition and non-transition substances applied on the material depend upon the t\ pe of transition desired on the final product and the nature of the stimulus to achie\ e the transition (i e thermochromic, photochromic etc )

In one embodiment, the process is carried out in a screen printing machine, wherein the transition, non-transition and/or poh mer coating is applied using a silk screen

In one embodiment of the process, one or more of the transition and non-transition substances is substantialh or completely free of phthalates and other undesirable compounds

In one embodiment of the process, the transition substance is applied to ha\ e a thickness of about 120μm after burning out cotton

In one embodiment of the in\ ention the non-transition substance is applied to ha\ e a thickness of 50-300 μm on the textile In another embodiment of the in\ ention the thickness of the non-transition substance is about 280 μm

Further the amount of the non-transition and transition substances to achie\ e the desired thickness can be calculated b} a skilled w orker depending upon the apparatus used to earn out the process The desired thickness can be achie\ ed b} using the appropriate apparatus For example, the thickness of 50-300μm of the non-transition substance and of 120μm for transition substance can be achie\ ed b} using screen printing apparatus, wherein the mesh size of the screen is 60-220 mesh, with a gentle and e\ en pressure

The steps of dn ing the textile after application of the acn lic coating, transition substance, non-transition-substance and/or poh mer coating can be achie\ ed b} an} method know n to a w orker skilled in the art In one embodiment of the in\ ention, the dr\ ing steps are carried out b} apph ing hot air

The step of curing can also be carried out according to methods known in the art In one embodiment of the in\ ention, the step of curing is carried out b} heating the textile in a curing o\ en at a constant temperature

In one embodiment the step of curing can be carried out under \ anable temperature within a set range In such an embodiment, the temperature increases, decreases or c\ cles within the range The temperature for the curing o\ en can range from 150 to 300 ⁰ F

As discussed abo\ e, the curing step in the process of the present in\ ention maj further comprise a step of pre-cuπng The step of pre-cuπng can be carried out b} heating the textile on a heating element prior to heating in the curing o\ en In one embodiment, the temperature of the heating element is about 200 ⁰ F

Indicator Devices

Indicator de\ ices made b} the process of the present in\ ention comprise a textile or fabric material, at least one transition substance coupled to the textile, and a poh mer coating The indicator de\ ices can further comprise at least one non-transition substance coupled to the textile to pro\ ide further information about the change in state indicated b} the transition substance

The indicator de\ices formed b} the process of the present in\ ention are for indicating changes in a state, for example change in temperature, exposure to heat, light and/or ultra\ iolet radiations, wherein the transition substance \ isualh transforms upon change in a state For example the colour of the transition substance can change in response to changes in temperature, moisture, or UV radiations The indicator device can be configured as a sheet of material and can be used to adhere, cover, or enclose, in whole or in part an entity.

In one embodiment of the present invention, the indicator device is configured to be attached to the clothing, for example as a label.

In one embodiment of the present invention, the indicator device is an article of clothing. The clothing described herein include for example, adult, child infant, or pet clothing, which can include shirts, blouses, t-shirts, tank tops, undershirts, hats, visors, headbands, pants, shorts, bathing suits, wetsuits, underwear, coats, jackets, junipers, sleepers, footwear, socks, tights, leotards, gloves, mittens, wrist bands, watches or other type of clothin ¹ gB a ^• s would be readilv understood bv a worker skilled in the art.

In another embodiment of the present invention, the indicator device is shaped in order to form a cover for an apparatus, for example a cover for furniture, chairs, strollers, car seats, bags, or other types of covers as w ould be readily understood by a worker skilled in the art. The fabric material may also be configured as a bag or other type of cam ing device as w ould be readily understood by a worker skilled in the art.

In another embodiment of the present invention, the indicator device is configured for a desired purpose, for example a towel, bed sheet, wash cloth, blanket, curtain, bandage, artwork, or other type of sheet-like product as w ould be readily understood by a worker skilled in the art.

In Fig. 1, the indicator device indicates changes in the temperature from above 0 degrees C to below -15 degrees C. As the temperature becomes colder, the colour and tone of the snowflake symbol become darker and more pronounced. This device may be coupled to a typical outer garment worn in a cold environment and may serve to alert the wearer and others as to a change in the temperature.

In Figs. 2a and 2b. the indicator device indicates changes in the temperature in contact Λλith the device, such as when the device is coupled to clothing worn by a child, such that the device is touching the skin. When the device is in contact with the body, as the temperature rises, the device changes to reveal, for example, wording to alert the child or caregiver of the high temperature. Examples of textiles coupled to such a device include a gown, sleeper or shirt Normal bod} temperature is about 37 degrees C A rise in the temperature, shown b} the change in condition on the indicator de\ice, indicates a rise in the child ^' s skin temperature, which can indicate o\ erheating, risk of fe\ er de\ elopment. etc The indicator de\ ices as illustrated in these figures change in response to different temperature conditions Other indicator de\ ices and corresponding temperature conditions are contemplated

In Figs 3a and 3b, the indicator de\ ice can be used to indicate changes in the temperature of fluids such as bath w ater or drinking fluids The indicator de\ice is in contact with the fluid As the temperature of the fluid changes, so do the s} mbols or icons on the de\ ice w hich is in contact w ith the fluid Examples of textiles coupled to such a de\ ice include a bathmit. bib and w ashcloth The indicator de\ ices as illustrated in these figures change in response to different temperature conditions Other indicator de\ ices and corresponding temperature conditions are contemplated

In Figs 4a and 4b, the indicator de\ ice indicates changes in the UV radiation so as to alert the w earer and others as to the likelihood of UV exposure As the relatπ e amount of

UV radiation exposure to the de\ice increases, for example, a sy mbol or icon of the sun ma} become darker and more pronounced Examples of textiles include swim w ear, a blanket, bod} suit and knit cap The indicator de\ ices as illustrated in these figures change in response to different UV conditions In one embodiment, a UV Index of 2 or less is considered low , 2-4 is considered moderate and 4 to 10 or higher is considered high to extremel} high Other indicator de\ ices and corresponding UV conditions are contemplated

Further examples of garments and accessories of the present im ention are contemplated

Transition Substance

The transition substances used in the process of the in\ ention are configured to change in the presence of or in response to a change in the condition/state For example, the transition substance can be a material that is responsπ e to changes in temperature, light, ultra\ iolet radiation, changes in pressure, changes in atmospheric composition (e g the presence or absence of certain gasses in the surrounding air), changes in moisture le\ el. changes in magnetic fields, etc The response of the transition substance to a change in a state is a \ isual change, such as colour change, reflecti\it\ change, or a transition from opaque to transparent

In one embodiment of the present in\ ention, the transition substance is configured to change re\ ersibh in response to a change in a condition/state For example, the transition substance can change colour in the presence of a stimulus which changes the condition/state and upon remo\ al of the stimulus the transition substance can re\ ert to its original colour

In one embodiment of the present in\ ention, the transition substance is configured to irre\ ersibh change in response to a change in a condition Upon the change of the transition substance as a result of a change in the condition, the transition substance is not capable of re\ erting to its original state For example, if the transition substance changed colour due to a change in the condition, this colour change is permanent

In one embodiment of the present in\ ention, the transition substance is configured to respond to a change in a condition b} changing from one \ isual representation to another For example, the transition substance maj respond to a change in a condition/state b} changing from one colour to another, or from one le\ el of reflectπ IΓΛ to another

In another embodiment of the present in\ ention, the transition substance is configured to respond to changes in a condition/state in \ an ing ranges, increments, or predetermined incremental steps For example, the transition substance ma} respond to incremental changes in temperature b} shifting through multiple changes in colour or shades of a particular colour For example, an incremental change in temperature can correspond to a specific colour or a specific shade of a particular colour, for the transition substance such that w hen the transition substance is w ithin a particular temperature range or increment, it is a specific colour For example, a transition substance maj appear blue at a cold temperature, } ellow as a w arm temperature and red at a hot temperature As another example, a transition substance maj appear white at a first UV radiation le\ el, light blue at a UV radiation le\ el denoting a UV index of 5, and na\} blue at a UV radiation le\ el denoted a UV index of 7 A w orker skilled in the art w ould readih understand other ranges, increments or predetermined incremental steps which ma\ be used for the identification of a defined chan *g£Λe in a condition/state

In one embodiment, the transition substance is configured to transform upon reaching a particular temperature or a particular UV le\ el

In one embodiment of the present in\ ention, the transition substance is configured to be responsπ e to stimulus resulting in a predetermined change in a condition/state, wherein the change is identified b} a particular threshold For example, if the condition is temperature, the transition substance can be configured to be responsπ e to a particular temperature and therefore a change in the condition is represented b} a temperature abo\ e or below the selected particular temperature In one embodiment, the present in\ ention can be used to e\ aluate bod} temperature, and the transition substance can be configured to be responsπ e when bod} heat reaches a particular le\ el, which can be defined as a fe\ er for example The definition of a particular threshold for other conditions w ould be readih understood b} a w orker skilled in the art For example, a threshold defining a particular ultra\ iolet radiation le\ el, a particular pressure le\ el or a particular moisture

In one embodiment, the transition substance is combined with other elements or substances so as to produce an additional result when the transition substance changes Examples of additional substances are, for example, magnetic substances, exothermic substances, luminescent substances, and the like

In one embodiment of the present in\ ention, the transition substance is applied in predetermined forms, shapes, and sizes For example the transition substance can be applied to the textile such that a predetermined image is created, wherein this predetermined image ma} or ma} not be \ isible in one of the original state, or changed state of the transition substance, when a condition is changed For example, in one embodiment of the present in\ ention, the transition substance is transparent upon initial coupling with the fabric material and upon interaction with a stimulus which changes the condition, the transition substance becomes a particular colour In another embodiment, the transition substance can change colour, for example from } ellow to red in response to a change in a condition, or other identifiable changes in the transition substance as w ould be readih understood b} a w orker skilled in the art

In one embodiment of the present in\ ention, the transition substance is applied in a predetermined shape that is eas> to read and understand For example the transition substance maj be formed in a predetermined shape which ma} be eas> to understand regardless of hteraα and colour-blindness In one embodiment, the transition substance is integrated into clothing, wherein the transition substance is configured to e\ aluate a condition associated with the w earer In one embodiment the transition substance, when integrated into clothing is configured to not ad\ erseh affect the comfort of the w earer

In one embodiment of the present inv ention, the preconfigured shape in which the transition substance is coupled to the fabric material is representatπ e of the particular condition for which the transition substance is responsπ e to changes In addition, for example, if the transition substance is responsπ e to an ultra\ iolet radiation state, the transition substance can be configured in the shape of the sun, as in Figs 4a and 4b In addition, if the transition substance is responsπ e to a temperature state, the transition substance can be configured in the shape of a thermometer, as in Figs 2a and 2b, or in the shape of a water droplet, as in Figs 3a and 3b A w orker skilled in the art w ould readih understand a \ ariet\ of different shapes in which the transition substance can be configured for coupling to the fabric material, wherein the condition is represented b} the shape

In another embodiment of the present in\ ention, the preconfigured shape of the transition substance maj be that of a geometrical shape such as a square, circle, triangle, rectangle, and the like, wherein a change in a condition can be indicated b} the appearance or disappearance of the geometrical shape

In one embodiment of the present in\ ention, the preconfigured shape and size of the transition substance is based on the number of changes in a condition that the transition substance is responsπ e to For example, the preconfigured shape and size of the transition substance can be selected to respond to one or more incremental changes in a condition such as the intensity of UV radiation le\ el In this embodiment, the response to each radiation le\ el w ould be indicated b} a different region of the transition substance In one embodiment of the present in\ ention, the transition substance is a thermochromic substance In one embodiment of the present in\ ention, the thermochromic substance is a thermochromic ink or d} e

Examples of thermochromic substances are liquid en stals and leucod} es In one embodiment both classes of substances are encapsulated in suitable microcapsules Liquid en stals change the en stal structures as the temperature rises and results in colourless materials Leucod} es require a combination of chemicals w orking together to change colours This SΛ stem is usualh protected in microcapsules at 3-5 microns The temperature to cause colour change ranges from -15°C (5°F) to 65°C (149°F) depending on the thermochromic inks It takes 2-4°C to change to clear Leuαxh es can withstand temperatures up to 250 ⁰ C, which is sufficient for com entional d} eing processes

In one embodiment of the present in\ ention, the transition substance is a photochromic substance In one embodiment of the present in\ ention. the photochromic substance is a photochromic ink or d} e

In one embodiment, the photochromic substance is formulated so that its threshold for colour change is ultra\ iolet radiation concentrations abo\ e UV index 5 In this embodiment the condition is the concentration of UV radiation and the threshold is the amount of UV radiation hkeh to cause sunburn

In one embodiment, the photochromic substance is formulated to be non-toxic when touched b} the skin or put into the mouth of a bab} or child In one embodiment, the photochromic substance is a leucodλ e, which is a pow der of microcapsules This leucod} e does not contain an} phthalates

Photochromic inks ha\ e special chemical structures When photochromic inks are exposed to a UV light source, it causes the inks to undergo a temporan chemical change in which the molecules are nearh broken in half and the colour changes When the UV source is remo\ ed. the molecules reform their original bonding structure and the colour returns Thermochromic and photochromic dyes also have low resistance to chlorine due to their chemical structures. In one embodiment of the present invention, a catalyst is added to the photochromic dye to provide increased resistance against salt w ater and chlorine.

Examples of the thermochromic and photochromic dyes are provided in Tables 1. 2 and 3.

Table 1 Colour range of thermochromic dye

Table 2 Temperature range (clearing point) of thermochromic dye

Table 3 Colour range of photochromic dye

Non-Transition substance

As discussed abo\ e, in one embodiment the indicator de\ ice formed b} the process of the present in\ ention comprises a non-transition substance coupled to the textile The non- transition substance can be applied under, o\ er and/or ad)acent to the transition substance In one embodiment of the present in\ ention, the non-transition substance is applied, alone or in combination with other elements, to the textile in predetermined forms, shapes, and sizes, which are \ isible either before or after the transition substance \isualh transforms upon a change in a condition

For example, in one embodiment of the present in\ ention, the non-transition substance is applied in combination with a transition substance, which transforms from transparent/colourless to a particular colour on change in a state In such an instance the non-transition substance w ould be \isible initialh and w ould be co\ ered b} the colour of the transition substance after transformation thereof In one embodiment the non-transition substance is applied in a predetermined shape or pattern that is eas} to read and understand In one embodiment of the present in\ ention, the preconfigured shape in which the non-transition substance is coupled to the fabric material is representatπ e of the particular condition which the transition substance is responsπ e to changes therein For example, if the transition substance is responsπ e to an ultra\ iolet radiation state, the non-transition substance can be configured in the shape of the sun And for example, if the transition substance is responsπ e to a temperature state, the non-transition substance can be configured in the shape of a thermometer or a w ater droplet

In one embodiment, the non-transition substance is applied in the shape of sun when used w ith the transition substance that is photochromic In one embodiment of the in\ ention, the non-transition substance is applied in the form of w ords, for example, ALERT, HOT ALERT, etc , when used in combination with transition substance that is thermochromic

In another embodiment of the present in\ ention, the preconfigured shape of the non- transition substance ma> be that of a geometrical shape such as a square, circle, triangle, rectan ¹ gSl ¹ e, and the like

In one embodiment of the present in\ ention, the non-transition substance is applied in a predetermined colour which is representatπ e of a reference for comparison relating to the condition indicated b} the transition substance For example, in one embodiment the non- transition substance is applied in the form of a red outer circle and the transition substance is applied in the shape of a sun or marked as "SUN ALERT ^" , wherein the transition substance is im isible or colourless in the absence of light and/or UV radiations and assumes the red colour of same or similar intensity as the outer circle to indicate the relatπ eh higher le\ els of UV radiations upon exposure to same

Various ft pes of non-transition substances known in the art can be used in the process of the present in\ ention Such substances include, but are not limited to reactπ e d} es, direct d} es, \ at d} es and pigments etc

Acrylic Coating In one embodiment of the invention, the textile or fabric material is coated with an acrylic coating before the step of applying the non-transition substance and/or transition substance. The acrylic coating is applied to impart strength to the material for handling during the coupling process and to improve the w ash fastness of the indicator device under various washing conditions, for example including bleaching or dry cleaning.

Various types of acrylic coatings known in the art can be used in the process of the present invention. Non limiting examples of such acrylic coatings include pory(methyl methacn late) [PMMA], poly (butyl methacn late) (PBMA), poly (ethyl methacrylate (PEMA), and poly (ethyl methacn late-co-butyl methacn late) [P (EMA-BMA)] etc.

Polymer Coating

In one embodiment of the invention, the textile material is coated with a polymer coating after applying the transition substance and/or non-transition substance. Again, the polymer coating to applied to improve the durability of the indicator device, in particular under various w ashing conditions, exposure to van ing temperatures, light and/or heat.

Various types of polymer coatings can be used in the process of the present invention. Non limiting examples of such polymer coatings include, poh butadiene, poh butadiene derivatives, polyurethane, polvurethane derivatives, styrene-butadiene, acn lonitrilebutadiene, acn lonitrile-butadiene-styrene, acn lonitrile-ethylene-styrene, poh acn lates, poh chloroprene, ethylene-vinyl acetate, etc.

Textile or Fabric Material

The textile or fabric material used in the process of the present invention can be a natural or man-made type sheet of material, for example a cotton material (100% cotton, poh /cotton blend), poh ester material, nylon material, acn lie, rayon, felt material, leather material, w ool material, hemp material, plastic material, or vinyl material.

Suitable labels can include vinyl or fabric patches, 100% cotton label tape, 100% poh ester label tape with fused or w oven edges, or label tapes that are blends of poh ester and cotton or other label configurations as w ould be know n to a w orker skilled in the art. In one embodiment of the present in\ ention, the colour of the fabric material is neutral In another embodiment, the fabric material is coloured The selection of the colour of the fabric material can be based on the predetermined shape of the transition substance, and/or the specific transition substance to be coupled to the fabric material For example, the colour of the fabric material can be chosen to be the same as that of the transition material before it has changed and to contrast with the colour of the transition material after it has changed in response to stimulus

The inv ention will now be described with reference to specific examples It will be understood that the following examples are intended to describe embodiments of the in\ ention and are not intended to limit the in\ ention in an} w a}

Example 1

In an exemplar} embodiment the process of the present in\ ention in\ oh es a process for making a roll of labels for affixing to articles for determining, for example, whether the temperature of bath w ater is too high This process in\ oh es pro\ iding a roll of cotton ribbon that is coated with acn lic coating A non-transition d} e is then applied on the ribbon in the form the w ord ALERT using silk screen ha\ ing a mesh size of 60-200 mesh w ith a constant, gentle and e\ en pressure The d} ed area of the roll is then dried w ith dn air for 10-15 seconds After the dn ing step, the coloured (e g , blue or \iolet) thermochromic d} e is applied in the form of a w ater droplet on the labels o\ er the w ord ALERT The thermochromic d} e is also applied using the silk screen ha\ing a mesh size of 60-200 mesh with a constant, gentle and e\ en pressure For w ater based thermochromic d} es, optimal ink penetration is obtained using with silk screens ha\ing a mesh size of 160 mesh with a constant, light and e\ en pressure After apph ing the thermochromic d} e, the d} ed areas of the labels are dried again with hot air for 10-15 seconds Then the label roll is coated with ACRAMIN™ or APPRETAN™ (poh mer coating) using the silk screen ha\ing a mesh size of 100-200 mesh After apph ing the poh mer coating the ribbon is passed o\ er a heating plate at temperatures and times ranging from about 200 ⁰ F for 10 seconds to about 300 ⁰ F for 7seconds to pre-cure the ribbon The ribbon is then rolled again and cured in a curing o\ en at a temperature of about 350 ⁰ F for 2 5 hours Finalh the ribbon is unrolled and passed through an electric heater tunnel for about a minute at 350 ⁰ F In this example, the thermochromic transition dye is coloured when the temperature of the bath water is within an acceptable range, and loses its colour to reveal the non- transition dye ALERT image below, when the temperature of the bath water is higher than 37.6 ⁰ C. In other tested examples, the temperature threshold is about 38°C (Fig. 3a) or 37°C (Fig. 3b).

Example 2

In an exemplar} embodiment the process of the present invention involves a process for making a roll of labels for affixing to articles of clothing to identity whether a person ^' s bod} temperature is above normal. This process involves providing a roll of cotton ribbon that is coated with acrylic coating. A non-transition dye is then applied on the ribbon in the form of the word ALERT using silk screen having a mesh size of 60-200 mesh with a constant, gentle and even pressure. The dyed area of the roll is then dried w ith dry air for 10-15 seconds. After the drying step, the coloured (e.g., blue or violet) thermochromic dye is applied in the form of a thermometer on the labels over the word ALERT. The thermochromic dye is also applied using the silk screen having a mesh size of 60-200 mesh with a constant, gentle and even pressure. After applying the thermochromic dye, the dyed areas of the labels are dried again w ith hot air for 10-15 seconds. Then the label roll is coated with ACRAMIN™ or APPRETAN™ using the silk screen having a mesh size of 100-200 mesh. After applying the polymer coating the ribbon is passed over a heating plate at temperatures and times ranging from about 200 ⁰ F for 10 seconds to about 300 ⁰ F for 7seconds to pre-cure the ribbon. The ribbon is then rolled again and cured in a curing oven at a temperature of about 350 ⁰ F for 2.5 hours. Finally the ribbon is unrolled and passed through an electric heater tunnel for about a minute at 350 ⁰ F. .

In this example, the thermochromic transition dye is coloured at a normal bod} temperature, and loses its colour to reveal the non-transition dye ALERT image below, as the bod} temperature approaches 38 ⁰ C (Fig. 2a). In another tested example, the dye does not completely lose its colour, but reveals the non-transition dye ALERT image below, as the bod} temperature approaches 38 ⁰ C (Fig. 2b).

Example 3 In an exemplar} embodiment the process of the present invention involves a process for making a roll of labels to indicate high levels of UV exposure. This process involves providing a roll of cotton ribbon that is coated with acrylic coating. A non-transition dye is then applied on the ribbon in the form of a pink circle using silk screen having a mesh size of 60-200 mesh with a constant, gentle and even pressure. The dyed area of the roll is then dried with dry air for 10-15 seconds. After the drying step, the photochromic dye is applied on the labels in the shape of a sun, within the pink outer circle. The photochromic dye is also applied using the silk screen having a mesh size of 60-200 mesh with a constant, gentle and even pressure. After applying the thermochromic dye, the dyed areas of the labels are dried again with hot air for 10-15 seconds. Then the label roll is coated with ACRAMIN™ or APPRETAN™ using the silk screen having a mesh size of 100- 200 mesh. After applying the polymer coating the ribbon is passed over a heating plate at temperatures and times ranging from about 200 ⁰ F for 10 seconds to about 300 ⁰ F for 7seconds to pre-cure the ribbon. The ribbon is then rolled again and cured in a curing oven at a temperature of about 350 ⁰ F for 2.5 hours. Finally the ribbon is unrolled and passed through an electric heater tunnel for about a minute at 350 ⁰ F. .

In this example, the photochromic transition dye is non-coloured at a low level of UV exposure, and becomes coloured as the level of UV exposure increases to indicate a level of UV exposure beyond an acceptable threshold level, for example at UV index 4 - 10 and higher, as illustrated in Figs. 4a and 4b.

Test Results

During testing of the samples it was observed that polymer coatings (especially ACRAMIN™), greatly improved the colour fastness of thermochromic and photochromic inks to dry cleaning and laundering. Colour fastness to dry cleaning was tested by the standard test method CAN/CGSB 4.2 No. 29.1-M89, and the colour change after dry cleaning w as evaluated by the AATCC grey scale. Test results are shown in Table 4.

Table 4 Colour Fastness to Dry Cleaning

Colour fastness to laundering w as tested by the standard test method CAN/CGSB 4.2 No. 19.1-2004 in the Launder-Ometer apparatus at 40 ⁰ F with 100 balls. The colour change after laundering w as evaluated by the AATCC grey scale. Test results are shown in Table

Table 5 Colour Fastness to Laundering

The application of polymer coatings to non-toxic photochromic substances formed from leucodyes did not effect the time of the colour change, while the application to thermochromic inks increased the time of the colour change by approximately 1-2 seconds.

During testing it was observed that the polymer coating did not improve the colour fastness of thermochromic inks to UV exposure. How ever, a worker skilled in the art w ill appreciate that the addition of a UV absorber w ill improve the colour fastness of thermochromic inks to UV exposure

It w as also observed during testing that fraying occurred with the 100% cotton label tape after extended handling and laundering. The substitution of a 100% cotton label tape with a sy nthetic backed coating prcnided the desired ink absorption and the sy nthetic backing pre\ ented the tape from fra> ing at its edges

During testing of the process for apph ing the thermochromic and photochrome d} es it w as obsen ed that the additional step in the dn ing process of passing the ribbon through an electric heater tunnel for minute at 350 ⁰ F pro\ ides impro\ ed scratch resistance

It w as also obsen ed during testing, that w hen the temperature of the coating exceeds the recommend temperature for the thermochromic d} e, the thermochromic d} e might o\ erheat and become contaminated Such contamination w as obsen ed to cause an undesired colour change in the thermochromic indicator