Activatable thermal indicator with blisters
AssigneeZebra Technologies Corporation
InventorsEric W. LIBERATO, Brian S. HUFFMAN, Mohannad ABDO
Life of this patent
Estimating the term…
Abstract
Activatable thermal indicators with blisters are disclosed herein. An example activatable environmental exposure indicator with a blister, includes a substrate; an indicator region; a reservoir in fluid communication with the indicator region; a blister covering the reservoir and having an internal surface; and a plurality of microcapsules, contained in the reservoir and covered by the blister; wherein applying a compressive force exceeding a predetermined threshold to the blister causes the blister to deform so the internal surface of the blister contacts the plurality of microcapsules, so that the activation action is applied to the plurality of microcapsules.
Claims23
An activatable environmental exposure indicator, comprising:
- a substrate;
- an indicator region;
- a reservoir in fluid communication with the indicator region;
- a blister covering the reservoir and having an internal surface;
- and
- a plurality of microcapsules, contained in the reservoir and covered by the blister;
- wherein each microcapsule of the plurality of microcapsules comprises a payload microencapsulated in a frangible shell,
- wherein the payload comprises a liquefiable material configured to liquefy responsive to a predetermined environmental exposure,
- wherein the frangible shells are configured to rupture responsive to an activation action, releasing the payload from the frangible shells, and
- wherein, after being released from the frangible shells, and responsive to the predetermined environmental exposure causing the liquefiable material to liquefy, the payload is configured to migrate into the indicator region producing an observable effect in the indicator region,
- wherein the frangible shells are configured to block the payload from migrating to the indicator region prior to the activation action,
- wherein applying a compressive force exceeding a predetermined threshold to the blister causes the blister to deform so the internal surface of the blister contacts the plurality of microcapsules, so that the activation action is applied to the plurality of microcapsules.
A method of forming an activatable environmental exposure indicator, comprising;
- providing a cover layer;
- forming a blister in the cover layer;
- depositing a plurality of microcapsules into the blister, each microcapsule of the plurality of microcapsules containing a payload microencapsulated in a frangible shell, the frangible shells configured to rupture responsive to an activation action and release the payload, the payload comprising a liquefiable material configured to liquefy responsive to a predetermined environmental exposure, the liquefiable material being retained by the frangible shells prior to rupture, and free to flow when liquefied after rupture of the frangible shells by the activation action;
- overlaying a wick onto the cover layer, the wick comprising an activation portion, a migration portion and an indicator portion, the wick adjacent to or in contact with the blister;
- overlaying a substrate onto the wick, microcapsules, and cover layer;
- and
- sealing the wick and the plurality of microcapsules between the cover layer and the substrate.
An article of manufacture comprising:
- a web of environmental exposure indicators, each indicator in the web of indicators demarcated by lines of weakness, each indicator in the web of substrates comprising:
- a substrate;
- an indicator region;
- a reservoir in fluid communication with the indicator region;
- a blister covering the reservoir and having an internal surface;
- and
- a plurality of microcapsules, contained in the reservoir and covered by the blister;
- wherein each microcapsule of the plurality of microcapsules comprises a payload microencapsulated in a frangible shell,
- wherein the payload comprises a liquefiable material configured to liquefy responsive to a predetermined environmental exposure,
- wherein the frangible shells are configured to rupture responsive to an activation action, releasing the payload from the frangible shells,
- wherein, after being released from the frangible shells, and responsive to the predetermined environmental exposure causing the liquefiable material to liquefy, the payload is configured to migrate into the indicator region producing an observable effect in the indicator region, and
- wherein the frangible shells are configured to block the payload from migrating to the indicator region prior to the activation action, wherein applying a compressive force exceeding a predetermined threshold to the blister causes the blister to deform so the internal surface of the blister contacts the plurality of microcapsules, so that the activation action is applied to the plurality of microcapsules.
Dependencies are inferred from the claim text.