Abstract: A temperature-activatable time-temperature indicator that can be used to monitor the historical exposure of a host product to ambient temperatures includes an optically readable, thermally sensitive indicator element. The indicator element can be inactive below a base temperature and is intrinsically thermally responsive at or above an activation temperature which is equal to or greater than the base temperature. The indicator can record cumulative ambient temperature exposure above the activation temperature irreversibly with respect to time. The indicator element can include a synthetic polymeric material, and optionally, a dye. A side-chain crystallizable polymer such as poly(hexadecylmethacrylate), that is solid below the base temperature and is a viscous liquid above the activation temperature can be employed. Intense indicator element colors can be obtained using an appropriate dye or dyes. Various structural configurations of indicator are described and illustrated.

Abstract: Described herein are temperature condition indicators (e.g. freezing, threshold temperature, thermal history indicators, etc.) comprising three phase emulsions. Methods of forming and using these indicators, and products that include these indicators, are also disclosed.

Abstract: A dual-function heat indicator for monitoring two or more modes of heat exposure is described. A manufacturing process for the dual-function heat indicator is also described. Dual-function heat indicators as described may be useful for monitoring the exposure of host products, with which the dual-function heat indicators may be associated, to cumulative ambient heat exposure and to a peak ambient heat exposure, and for other purposes.

Abstract: A dual-function heat indicator for monitoring two or more modes of heat exposure is described. A manufacturing process for the dual-function heat indicator is also described. Dual-function heat indicators as described may be useful for monitoring the exposure of host products, with which the dual-function heat indicators may be associated, to cumulative ambient heat exposure and to a peak ambient heat exposure, and for other purposes.

Abstract: A freeze indicator including an indicator dispersion is described herein. Such an indicator dispersion can include: a liquid medium and particles of a colored indicator agent dispersed in the liquid medium. The colored indicator agent particles having an inherent color; wherein the indicator dispersion exhibits the inherent color of the colored indicator agent particles after freezing and is configured to have a less colored appearance before freezing and wherein light scattering masks the inherent color of the colored indicator agent particles before freezing. Some indicator dispersions can be free of color-changing chemical co-reactants. These freeze indicators can be small, have a low cost, and have a simple configuration.

Abstract: A freeze indicator including an indicator dispersion is described herein. Such an indicator dispersion can include: a liquid medium and particles of a colored indicator agent dispersed in the liquid medium. The colored indicator agent particles having an inherent color; wherein the indicator dispersion exhibits the inherent color of the colored indicator agent particles after freezing and is configured to have a less colored appearance before freezing and wherein light scattering masks the inherent color of the colored indicator agent particles before freezing. Some indicator dispersions can be free of color-changing chemical co-reactants. These freeze indicators can be small, have a low cost, and have a simple configuration.

Abstract: A dual-function heat indicator for monitoring two or more modes of heat exposure is described. A manufacturing process for the dual-function heat indicator is also described. Dual-function heat indicators as described may be useful for monitoring the exposure of host products, with which the dual-function heat indicators may be associated, to cumulative ambient heat exposure and to a peak ambient heat exposure, and for other purposes.

Abstract: Described herein are temperature condition indicators (e.g. freezing, threshold temperature, thermal history indicators, etc.) comprising three phase emulsions. Methods of forming and using these indicators, and products that include these indicators, are also disclosed.

Abstract: Crystallized diacetylenic compounds having certain crystallographic and other characteristics; diacetylenic compounds and mixtures crystallized from diacetylenic solutions; methods of preparing and identifying solvent systems for dissolving diacetylenic compounds; diacetylenic solutions; methods of recrystallizing diacetylenic compounds; crystals of 2,4-hexadiyn-1,6-bis(alkylurea) compounds; and ambient condition indicators and time-temperature condition indicators comprising crystallized diacetylenic compounds.

Abstract: A temperature-activatable time-temperature indicator that can be used to monitor the historical exposure of a host product to ambient temperatures includes an optically readable, thermally sensitive indicator element. The indicator element can be inactive below a base temperature and is intrinsically thermally responsive at or above an activation temperature which is equal to or greater than the base temperature. The indicator can record cumulative ambient temperature exposure above the activation temperature irreversibly with respect to time. The indicator element can include a synthetic polymeric material, and optionally, a dye. A side-chain crystallizable polymer such as poly(hexadecylmethacrylate), that is solid below the base temperature and is a viscous liquid above the activation temperature can be employed. Intense indicator element colors can be obtained using an appropriate dye or dyes. Various structural configurations of indicator are described and illustrated.

Abstract: A temperature-activatable time-temperature indicator that can be used to monitor the historical exposure of a host product to ambient temperatures includes an optically readable, thermally sensitive indicator element. The indicator element can be inactive below a base temperature and is intrinsically thermally responsive at or above an activation temperature which is equal to or greater than the base temperature. The indicator can record cumulative ambient temperature exposure above the activation temperature irreversibly with respect to time. The indicator element can include a synthetic polymeric material, and optionally, a dye. A side-chain crystallizable polymer such as poly(hexadecylmethacrylate), that is solid below the base temperature and is a viscous liquid above the activation temperature can be employed. Intense indicator element colors can be obtained using an appropriate dye or dyes. Various structural configurations of indicator are described and illustrated.

Abstract: A freeze indicator including an indicator dispersion is described herein. Such an indicator dispersion can include: a liquid medium and particles of a colored indicator agent dispersed in the liquid medium. The colored indicator agent particles having an inherent color; wherein the indicator dispersion exhibits the inherent color of the colored indicator agent particles after freezing and is configured to have a less colored appearance before freezing and wherein light scattering masks the inherent color of the colored indicator agent particles before freezing. Some indicator dispersions can be free of color-changing chemical co-reactants. These freeze indicators can be small, have a low cost, and have a simple configuration.

Abstract: A dual-function heat indicator for monitoring two or more modes of heat exposure is described. A manufacturing process for the dual-function heat indicator is also described. Dual-function heat indicators as described may be useful for monitoring the exposure of host products, with which the dual-function heat indicators may be associated, to cumulative ambient heat exposure and to a peak ambient heat exposure, and for other purposes.

Abstract: Crystallized diacetylenic compounds having certain crystallographic and other characteristics; diacetylenic compounds and mixtures crystallized from diacetylenic solutions; methods of preparing and identifying solvent systems for dissolving diacetylenic compounds; diacetylenic solutions; methods of recrystallizing diacetylenic compounds; crystals of 2,4-hexadiyn-1,6-bis(alkylurea) compounds; and ambient condition indicators and time-temperature condition indicators comprising crystallized diacetylenic compounds.

Abstract: Crystallized diacetylenic compounds having certain crystallographic and other characteristics; diacetylenic compounds and mixtures crystallized from diacetylenic solutions; methods of preparing and identifying solvent systems for dissolving diacetylenic compounds; diacetylenic solutions; methods of recrystallizing diacetylenic compounds; crystals of 2,4-hexadiyn-1,6-bis(alkylurea) compounds; and ambient condition indicators and time-temperature condition indicators comprising crystallized diacetylenic compounds.

Abstract: An optically readable ambient condition history indicator can have a substrate, an indicator agent on the substrate surface, and a transparent layer overlying the indicator agent. The indicator agent can be capable of changing appearance in response to exposure to an ambient condition and the transparent layer can be subject to exposure to environmental ultraviolet radiation. The indicator can also include a radiation-filtering adhesive layer overlying the indicator agent to secure the transparent layer to the indicator agent, which adhesive layer can include an adhesive and an ultraviolet radiation filter and can contact both the transparent layer and the indicator agent-bearing substrate. The radiation-filtering adhesive layer can protect the indicator agent from ultraviolet radiation transmitted through the transparent layer and provide a simple, robust construction that is easy to manufacture and resists delamination. The adhesive itself is also protected from ultraviolet radiation.

Abstract: Indicator inks, indicators formed by printing or otherwise utilizing the inks and host products utilizing the indicators are disclosed. Reactivity-enhancing adjuvants stimulate enhanced thermal reactivity of diacetylenic or other indicator agents capable of responding to ambient thermal conditions with a visual change signaling an end point. The diacetylenic or other agents may be sensitive or relatively insensitive to ambient temperatures. Use of a reactivity-enhancing adjuvant provides a useful means for adapting the reactivities of indicator agents to the response characteristics of prospective host products, for example perishables such as vaccines or fresh fish and maturables such as fruit, cheese and wine. Some exemplary adjuvants include low-temperature polymerization initiators, for example methyl ethyl ketone peroxide and polymerization accelerators, for example cobalt compounds. Such initiators and accelerators can also be used in combination.

Abstract: A color-changing emulsion for use in a freeze indicator can employ a dispersion medium, for example, an aqueous liquid, a first reactant phase and a second reactant phase, which two reactant phases can both be dispersed in the dispersion medium. The first reactant phase includes a hydrophobic liquid and a first reactant, for example, a color precursor such as a leuco dye. The second reactant phase can include a hydrophobic liquid, and includes, or can be, a second reactant, for example, a color developer such as a leuco dye developer. The first and second reactant phases can be essentially unmixed, and can be co-reactable to provide a color change. In response to a freezing temperature, the color-changing emulsion can coagulate and change color irreversibly. An intense color change can be obtained by using, for example, a suitable leuco dye precursor and developer.

Abstract: Solid polymerizable diacetylenic monomer compositions, including compositions co-crystallized from a diversity of solvent systems under diverse cooling conditions, can exhibit diffraction patterns associated with the color development reactivities of the compositions. High reactivity compositions are disclosed and high reactivity and low reactivity phases can be identified. A low angle powder X-ray diffraction peak can indicate the presence of one or more crystal phases in a composition. A fingerprint region can exhibit fingerprint patterns of diffraction peaks associated with different reactivities. Information about polymerization of the diacetylenic monomers is disclosed using 13C nuclear magnetic resonance (“NMR”) characterization. Diacetylenic monomer compositions useful in ambient condition indicators, for example time-temperature indicators are disclosed.

Abstract: Crystallized diacetylenic compounds having certain crystallographic and other characteristics; diacetylenic compounds and mixtures crystallized from diacetylenic solutions; methods of preparing and identifying solvent systems for dissolving diacetylenic compounds; diacetylenic solutions; methods of recrystallizing diacetylenic compounds; crystals of 2,4-hexadiyn-1,6-bis(alkylurea) compounds; and ambient condition indicators and time-temperature condition indicators comprising crystallized diacetylenic compounds.