Color-changing environmental stimulus indicator with reference of variable appearance

Patent metadata

Field	Value
Publication number	US-11435294-B2
Application number	US-201715723693-A
Country	US
Kind code	B2
Filing date	Oct 3, 2017
Priority date	Oct 12, 2016
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

A color-changing environmental stimulus indicator includes a substrate, an active indicator placed above the substrate, and a reference component. The active indicator is configured to change color in response to an environmental stimulus. The reference component is also color changeable in response to an environmental stimulus. The reference component is configured to have a similar appearance to the active indicator at an end point. The environmental stimulus includes one or more of temperature, cumulative temperature, humidity, pH, and ultraviolet radiation.

First claim

The invention claimed is:

1. A color-changing environmental stimulus indicator comprising:
a substrate;
an active indicator overlaying the substrate; and
a reference component overlaying the substrate,
wherein the active indicator and the reference component are configured to both be exposed to the same environmental stimulus conditions over time and are both color changeable in response to cumulative exposure over time to the environmental stimulus;
wherein the color change of the active indicator and the reference component is irreversible and is at least one selected from the group consisting of a change in hue, a change in darkness, a change in color density, a change in fluorescence, and a change in opacity;
wherein an end point of the environmental stimulus indicator occurs after a predetermined cumulative exposure over time to the environmental stimulus and is detectable by comparison of the active indicator to the reference component; and
wherein the reference component is a combination of a color-changing material overlaying a non-color changing material that is visible through the color changing material in at least some color states of the color-changing material.

2. The color-changing environmental stimulus indicator of claim 1 , wherein both the active indicator and the reference component are configured to darken in response to cumulative exposure over time to the environmental stimulus.

3. The color-changing environmental stimulus indicator of claim 1 , wherein at least one of the active indicator and the reference component change color by using a technique selected from the group consisting of a color changing ink, metal etching, dye diffusion, acid/base reactions, and combinations thereof.

4. The color-changing environmental stimulus indicator of claim 1 , further comprising an ultraviolet radiation filter configured to protect at least one of the active indicator and the reference component from exposure to ultraviolet radiation.

5. A temperature-sensitive product, comprising:
a temperature perishable host product;
a container containing the host product; and
the color-changing environmental stimulus indicator of claim 1 ,
wherein the color-changing environmental stimulus indicator is attached to the container.

6. The temperature-sensitive product of claim 5 , wherein the host product is selected from the group consisting of a vaccine, a drug, a medication, a pharmaceutical, a cosmeceutical, a nutricosmetic, a nutritional supplement, a biological material, and a food stuff.

7. The temperature-sensitive product of claim 5 , wherein the host product is a vaccine and the container is a vaccine vial.

8. The temperature-sensitive product of claim 5 ,
wherein the active indicator and the reference component change color in response to the same environmental stimulus; or
wherein the active indicator and the reference component change color in response to different environmental stimuli; or
wherein the active indicator is configured to darken in response to exposure to the environmental stimulus and the reference component is configured to lighten in response to exposure to the environmental stimulus; or
wherein both the active indicator and the reference component are configured to darken or lighten in response to exposure to the environmental stimulus preferably at different rates; or
wherein the reference component is configured to change color with time.

9. The temperature-sensitive product of claim 5 , wherein at least one of the active indicator and the reference component change color by using a technique selected from the group consisting of a color changing ink, metal etching, dye diffusion, acid/base reactions, and combinations thereof.

10. The temperature-sensitive product of claim 5 , further comprising an ultraviolet radiation filter configured to protect the active indicator or the reference component from exposure to ultraviolet radiation.

11. The color-changing environmental stimulus indicator of claim 1 , wherein both the active indicator and the reference component are configured to lighten in response to cumulative exposure over time to the environmental stimulus.

12. The color-changing environmental stimulus indicator of claim 1 , wherein the reference component color changing material is placed over the reference component constant-color material, so that, when the reference component color changing material is in an initial state, the reference component constant-color material is visible through the reference component color changing material.

13. The color-changing environmental stimulus indicator of claim 1 , wherein the reference component consists essentially of a single color changing material.

14. A color-changing environmental stimulus indicator comprising:
a substrate;
an active indicator placed overlaying the substrate and configured to change color in response to cumulative temperature exposure over time; and
a reference component overlaying the substrate and configured to change color in response to an environmental stimulus,
the environmental stimulus indicator having an end state determinable by comparison of the color of the reference component and the color of the active indicator,
wherein the active indicator and the reference component are together configured to indicate in the end state that cumulative temperature exposure over time has exceeded a predetermined threshold; and
wherein both the active indicator and the reference component are configured to darken in response to cumulative temperature exposure over time at different rates, the reference component having an initial color state, wherein the color-changing environmental stimulus indicator has a higher effective activation energy than a second environmental stimulus indicator with the an identical active indicator and a fixed color state reference component having a color that is the same as the initial state of the reference component.

15. The color-changing environmental stimulus indicator of claim 14 , wherein the reference component is configured to change color in response to exposure to at least one of humidity, pH, and ultraviolet radiation.

16. The color-changing environmental stimulus indicator of claim 15 , wherein the reference component is configured to lighten in response to exposure to the at least one of humidity, pH, and ultraviolet radiation.

17. The color-changing environmental stimulus indicator of claim 14 , wherein
the active indicator is configured to darken in response to a cumulative exposure to temperature over time and the reference component is configured to lighten in response to the cumulative exposure to temperature over time such that the color-changing environmental stimulus indicator has a lower effective activation energy than the active indicator.

18. A temperature-sensitive product, comprising:
a temperature perishable host product;
a container containing the host product; and
the color-changing environmental stimulus indicator of claim 14 ,
wherein the color-changing environmental stimulus indicator is attached to the container.

19. A color-changing environmental stimulus indicator comprising: a substrate;
an indicator component comprising an indicator material which is color-changeable in response to cumulative temperature exposure over time;
a reference component comprising a reference material;
wherein the reference material is color-changeable in response to an environmental stimulus other than temperature;
wherein the indicator component and the re

Assignees

• Temptime Corp

Inventors

• Abdo Mohannad
• Grabiner Frederick Robert
• Smith Dawn E

Classifications

• G01N31/22

  using chemical indicators (G01N31/02 takes precedence) · CPC title

• G01N21/78 Primary

  producing a change of colour · CPC title

• G01N21/81

  Indicating humidity · CPC title

• G01N21/80

  Indicating pH value · CPC title

• G01N2021/7786

  Fluorescence · CPC title