This invention relates to thin indicating devices, such as time-temperature indicators and a method of making by applying and UV curing one or more layers of indicating composition are disclosed. For example, an indicator layer is applied on substrate and cured with UV light, immediately followed by an application of an activator layer which is cured by UV light. The device can have other layers, such as a permeable barrier between the activator and indicator layer and a top protective layers which are also UV cured. This fast curing method prevents premature reactions, e.g., diffusion of activator into indicator layer and vice versa during manufacturing.

This invention relates to thin indicating devices, such as time-temperature indicators and a method of making by applying and UV curing one or more layers of indicating composition are disclosed. For example, an indicator layer is applied on substrate and cured with UV light, immediately followed by an application of an activator layer which is cured by UV light. The device can have other layers, such as a permeable barrier between the activator and indicator layer and a top protective layers which are also UV cured. This fast curing method prevents premature reactions, e.g., diffusion of activator into indicator layer and vice versa during manufacturing.

A temperature exposure indicator includes a reservoir of meltable material having a melting point at an activation threshold of the temperature exposure indicator. The temperature exposure indicator also includes a light scattering material having voids and an indicia overlayed by the light scattering material such that the indicia is initially obscured by the light scattering material prior to the meltable material being exposed to a temperature above the activation threshold. The reservoir is in fluid communication with the light scattering material, such that the meltable material, when exposed to a temperature at or above the activation threshold, is configured to melt and flow into the voids of the light scattering material thereby causing the light scattering material to transition from an obscuring form to a non-obscuring form so that the indicia is viewable through the light scattering material.

A temperature exposure indicator includes a reservoir of meltable material having a melting point at an activation threshold of the temperature exposure indicator. The temperature exposure indicator also includes a light scattering material having voids and an indicia overlayed by the light scattering material such that the indicia is initially obscured by the light scattering material prior to the meltable material being exposed to a temperature above the activation threshold. The reservoir is in fluid communication with the light scattering material, such that the meltable material, when exposed to a temperature at or above the activation threshold, is configured to melt and flow into the voids of the light scattering material thereby causing the light scattering material to transition from an obscuring form to a non-obscuring form so that the indicia is viewable through the light scattering material.

An apparatus, system and method for a time temperature indicator (TTI) which is capable of providing a summary of the time and temperature history of a good to which it is coupled, optionally including with regard to providing an indication as to whether one or more temperature thresholds have been breached. According to other embodiments, the TTI specifically provides an indication as to whether a temperature threshold at or around the freeze point has been breached, optionally even without providing a time and temperature history.

A purpose of the present invention is to provide a temperature history indicator that allows for visual confirmation of whether the temperature is at or below a prescribed temperature as well as simple conversion of this information into data. A temperature history indicator according to the present invention is characterized by being provided with a label layer and a temperature-indicating layer laminated above or below the label layer, wherein the temperature-indicating layer includes a substance having at crystallization starting temperature of 10° C. or lower and a melting point at least 20° C. higher than the crystallization starting temperature.

A purpose of the present invention is to provide a temperature history indicator that allows for visual confirmation of whether the temperature is at or below a prescribed temperature as well as simple conversion of this information into data. A temperature history indicator according to the present invention is characterized by being provided with a label layer and a temperature-indicating layer laminated above or below the label layer, wherein the temperature-indicating layer includes a substance having at crystallization starting temperature of 10° C. or lower and a melting point at least 20° C. higher than the crystallization starting temperature.

The present invention addresses the problem of providing a temperature sensing body capable of sensing both a temperature increase and a temperature decrease, and having an anti-tampering function. In order to solve said problem, this temperature sensing body is characterized by including: a first ink in which a temperature T.sub.a1 for initiating color disappearance when the temperature rises and a temperature T.sub.d1 for initiating color development when the temperature falls are different; and a second ink in which a temperature T.sub.a2 for initiating color disappearance when the temperature rises and a temperature T.sub.d2 for initiating color development when the temperature falls are different, wherein the temperature T.sub.a1 for initiating color disappearance, the temperature T.sub.d1 for initiating color development, the temperature T.sub.a2 for initiating color disappearance, and the temperature T.sub.d2 for initiating color development have the relationship, T.sub.d1<T.sub.d2<T.sub.a1<T.sub.a2.

The present invention addresses the problem of providing a temperature sensing body capable of sensing both a temperature increase and a temperature decrease, and having an anti-tampering function. In order to solve said problem, this temperature sensing body is characterized by including: a first ink in which a temperature T.sub.a1 for initiating color disappearance when the temperature rises and a temperature T.sub.d1 for initiating color development when the temperature falls are different; and a second ink in which a temperature T.sub.a2 for initiating color disappearance when the temperature rises and a temperature T.sub.d2 for initiating color development when the temperature falls are different, wherein the temperature T.sub.a1 for initiating color disappearance, the temperature T.sub.d1 for initiating color development, the temperature T.sub.a2 for initiating color disappearance, and the temperature T.sub.d2 for initiating color development have the relationship, T.sub.d1<T.sub.d2<T.sub.a1<T.sub.a2.

An apparatus, system and method for a time temperature indicator (TTI) which is capable of providing a summary of the time and temperature history of a good to which it is coupled, optionally including with regard to providing an indication as to whether one or more temperature thresholds have been breached. According to other embodiments, the TTI specifically provides an indication as to whether a temperature threshold at or around the freeze point has been breached, optionally even without providing a time and temperature history.