TEMPERATURE INDICATOR
A temperature indicator includes a transparent substrate with a first code and a second code disposed on a first side of the transparent substrate. The first code comprises a first color and the second code comprises a second color different than the first color. An absorbent medium is disposed on a second side of the transparent substrate opposite the first side and comprises a third color that contrasts with only the second color of the first and second colors. A substance is disposed between the absorbent medium and the transparent substrate. The substance comprises a fourth color that contrasts with only the first color of the first and second colors and is meltable and absorbed by the absorbent medium in response to a temperature exceeding a temperature threshold.
1 . A temperature indicator, comprising:
a transparent substrate;
a first portion of a first code and a second portion of a second code disposed on a first side of the transparent substrate, the first portion comprising a first color, the second portion comprising a second color different than the first color;
an absorbent medium disposed on a second side of the transparent substrate opposite the first side, the absorbent medium comprising a third color that contrasts with only the second color of the first and second colors; and
a substance disposed between the absorbent medium and the transparent substrate, the substance comprising a fourth color that contrasts with only the first color of the first and second colors, the substance meltable and absorbed by the absorbent medium in response to a temperature exceeding a temperature threshold.
2 . The temperature indicator of claim 1 , wherein the first code and the second code comprise a respective first quick response (QR) code and a second QR code.
3 . The temperature indicator of claim 1 , wherein, responsive to the substance being absorbed by the absorbent medium, the first code is unreadable.
4 . The temperature indicator of claim 1 , wherein, prior to the substance being absorbed by the absorbent medium, the second code is unreadable.
5 . The temperature indicator of claim 2 , wherein the substance is disposed in alignment with at least one of a position detection marker of the first QR code.
6 . The temperature indicator of claim 1 , wherein the first code is spaced apart from the second code.
7 . The temperature indicator of claim 1 , wherein the first code represents a non-actuated state of the temperature indicator and the second code represents an actuated state of the temperature indicator.
8 . A temperature indicator, comprising:
a code layer comprising at least a first portion of a code, the code representing a non-actuated state of the temperature indicator;
a substrate layer; and
a compound layer disposed between the code layer and the substrate layer, the compound layer comprising a substance responsive to a temperature change and, responsive to the temperature indicator being exposed to a temperature threshold, the substance changes to a color impairing readability of the code.
9 . The temperature indicator of claim 8 , wherein the substance comprises a thermochromic substance.
10 . The temperature indicator of claim 8 , wherein the first portion of the code is applied to a top side of the compound layer.
11 . The temperature indicator of claim 8 , wherein the substrate layer forms at least a second portion of the code.
12 . The temperature indicator of claim 8 , wherein, in a non-actuated state, the substrate layer is visible through the compound layer.
13 . The temperature indicator of claim 8 , wherein the first portion of the code comprises a first color, and wherein the substance changes to a second color lacking contrast to the first color.
14 . The temperature indicator of claim 8 , wherein the compound layer is substantially transparent in the non-actuated state.
15 . A temperature indicator, comprising:
a substrate having a first side and second side opposite the first side;
a first portion of a code disposed on the first side of the substrate, the first portion comprising a first color; and
a substance disposed on the second side of the substrate, the substance comprising a second color contrasting with the first color and forming a second portion of the code at a first temperature, and wherein responsive to the substance being exposed to a second temperature meeting a temperature threshold of the substance, the substance changes from the second color to a third color, the third color impairing readability of the code.
16 . The temperature indicator of claim 15 , wherein the substance comprises a thermochromic substance.
17 . The temperature indicator of claim 15 , wherein the code comprises a quick response (QR) code.
18 . The temperature indicator of claim 17 , wherein the substance is disposed in alignment with at least one of a position detection marker of the QR code.
19 . The temperature indicator of claim 15 , wherein the third color matches the first color.
20 . The temperature indicator of claim 15 , wherein the substrate comprises a transparent substrate.