Abstract: A printable ink for reversible thermal indicators that includes microcapsules retaining therein a core material that is opaque as a solid and transparent as a liquid, and a binder and a rheology modifier as a carrier for the microcapsules. The binder and the rheology modifier are either the same substance or different substances. The microcapsules in the printable ink retain the core material therein for repeated, reversible transitions from solid to liquid and liquid to solid.

Abstract: Visual and electronically readable temperature indicators and methods of making the same have an electric circuit with a microchip and a bridge within the circuit, and a facing material over the electric circuit. The bridge includes either a single layer or multiple layers that include a conductive material, a phase change material having a pre-selected melt temperature, a binder, a first colorant that is soluble in the phase change material and/or a second colorant that is a special effect pigment. In operation, at temperatures below the pre-selected melt temperature, the bridge is electrically conductive, and at a temperature at or above the pre-selected melt temperature, the phase change material melts and dilutes the conductive material, so that the bridge is electrically non-conductive, and a color change occurs that is visible to the user through the facing material such as through a transparent window or in an absorbent material.

Abstract: A printable ink for reversible thermal indicators that includes microcapsules retaining therein a core material that is opaque as a solid and transparent as a liquid, and a binder and a rheology modifier as a carrier for the microcapsules. The binder and the rheology modifier are either the same substance or different substances. The microcapsules in the printable ink retain the core material therein for repeated, reversible transitions from solid to liquid and liquid to solid.