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 freeze indicator can include an indicator dispersion having an aqueous liquid medium and organic material indicator particles dispersed in the aqueous liquid medium. The indicator dispersion can have an initial appearance before freezing and an irreversibly different appearance after freezing and can exhibit a freeze-onset temperature of about ?1.9° C. or higher. Some factors helpful to providing a relatively high freeze onset temperature are employment of a proteinaceous ice-nucleating agent, control of pH, use of a protein stabilizer and control of the ratio of protein stabilizer to ice-nucleating agent.

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: Freeze indicators providing a visual indication of exposure of the freeze indicator to a freezing or near-freezing temperature and their manufacture are disclosed. The freeze indicators employ colloidal dispersions as active elements and include flexible freeze indicators, freeze indicators protected against drying out and freeze indicators employing core shell composites, for example gold coated pigments as active indicator elements. Also disclosed are: a combination freeze indicator and threshold temperature indicator; a combination threshold indicator and cumulative temperature indicator; and three-way combination indicators that can provide indications of cumulative past temperature exposure, exposure to freezing temperatures and exposure to a temperature above a threshold.

Abstract: Freeze indicators can include an indicator dispersion, a liquid medium, indicator particles dispersed in the liquid medium and a particulate inorganic nucleating agent to inhibit supercooling of the liquid medium. The inorganic nucleating agent can have an ionic surface coating which can help provide a sharp end point. Optionally, freeze indicators can include indicator particles comprising an organic material and a softener to soften the indicator particles and provide the freeze indication with an enhanced visual appearance. Another option is to provide a temperature-sensitive stabilizer to inhibit coagulation of the indicator dispersion at temperatures above the liquid medium frozen state melting point while permitting coagulation of the indicator dispersion at the liquid medium frozen state melting point.

Abstract: A product shelf life monitoring system comprises a label substrate bearing upon a limited portion of its area an active indicator composition responsive to varying temperature over time to effect a visible change in color density or the like. The susceptibility of the indicator composition to similarly respond to incidence of vagrant ultraviolet light is ameliorated by application of an area of ultraviolet light absorbent composition in register above the indicator composition and extending at most only slightly beyond the periphery of the area of indicator composition. In this manner, the remaining area of the label is preserved for ultraviolet light responsive implementations, and only a minimal, economical amount of ultraviolet light absorbent composition is expended.

Abstract: A freeze indicator employs, as active indicator element, dispersion of solid particles in a liquid medium which can be water or aqueous and which coagulates to provide an irreversible appearance change when subject to freezing. The liquid dispersion can be contained in an indicator volume around which extends a vapor block layer. The vapor block layer can prevent loss of liquid vapor from the dispersion and consequent drying out and dysfunctionality of the freeze indicator. For containing an aqueous medium, bilayer and trilayer laminate materials can be used which have a low water vapor transmission rate. The active indicator element can be a dilute colloidal dispersion of a metal such as gold or silver or other inorganic pigment material in water or an aqueous medium. Some embodiments avoid use of dispersants and the like and employ an active indicator element consisting of inorganic pigment particles, water and optionally an ice nucleating agent.

Abstract: Freeze indicators providing a visual indication of exposure of the freeze indicator to a freezing or near-freezing temperature and their manufacture are disclosed. The freeze indicators employ colloidal dispersions as active elements and include flexible freeze indicators, freeze indicators protected against drying out and freeze indicators employing core shell composites, for example gold coated pigments as active indicator elements. Also disclosed are: a combination freeze indicator and threshold temperature indicator; a combination threshold indicator and cumulative temperature indicator; and three-way combination indicators that can provide indications of cumulative past temperature exposure, exposure to freezing temperatures and exposure to a temperature above a threshold.

Abstract: An excess temperature indicator can provide a visual indication of past exposure of perishable, maturing and other host products to an elevated temperature exceeding a threshold temperature. The indicator can have an upper layer provided with a viewing window and a wick attached to the upper layer. A reservoir of heat-fusible indicator material can be disposed in contact with the wick, to fuse and move along the wick changing the visual appearance of a first portion of the wick viewable through the window, in response to an excess temperature event. Also, the indicator can have a region of fused upper layer material attaching the wick to the upper layer. Optionally, a window seal can extend around the viewing window to prevent migration of the indicator material. The indicator can be employed to monitor vaccines, foods and other products providing an enduring visual signal of exposure to potentially damaging temperature conditions.

Abstract: A combination temperature exposure indicator suitable for attachment to, or association with, a host product has a substrate, a freeze indicator supported by the substrate and a cumulative ambient time-temperature indicator also supported by the substrate. The freeze indicator can provide a visual indication of exposure of the freeze indicator to a freezing or near-freezing temperature and the cumulative time-temperature indicator can provide a visual indication of exposure of the cumulative time-temperature indicator to a predetermined cumulative time-temperature value. Also disclosed are: a combination freeze indicator and threshold temperature indicator; a combination threshold indicator and cumulative temperature indicator; and three-way combination indicators that can provide indications of cumulative past temperature exposure, exposure to freezing temperatures and exposure to a temperature above a threshold.

Abstract: A freeze indicator employs, as active indicator element, dispersion of solid particles in a liquid medium which can be water or aqueous and which coagulates to provide an irreversible appearance change when subject to freezing. The liquid dispersion can be contained in an indicator volume around which extends a vapor block layer. The vapor block layer can prevent loss of liquid vapor from the dispersion and consequent drying out and dysfunctionality of the freeze indicator. For containing an aqueous medium, bilayer and trilayer laminate materials can be used which have a low water vapor transmission rate. The active indicator element can be a dilute colloidal dispersion of a metal such as gold or silver or other inorganic pigment material in water or an aqueous medium. Some embodiments avoid use of dispersants and the like and employ an active indicator element consisting of inorganic pigment particles, water and optionally an ice nucleating agent.

Abstract: A combination RFID tag intended to be associated with a host product, for example by being secured to the outside of a package containing a perishable product, e.g. foodstuffs or vaccines, which RFID tag is provided with a visually readable environmental condition exposure indicator. The visual indicator can sense the exposure of the RFID tag to an environmental condition e.g. temperature, experienced by the host product providing a visual indication, e.g. a color change, readable externally of the RFID tag of the sensed environmental condition. The visual indicator can be chemically active, for example an acetylenic agent, and may be responsive to cumulative temperature excursions over time. The novel RFID tag 11 and tag inspection methods of the invention permit an efficacious harnessing of information about the condition exposure history of a specific inventory item including product identification and related data.

Abstract: A quality assurance system having an ambient condition indicator provides a current visual indication of the cumulative exposure over time of a host product to an ambient condition such as temperature or humidity. The indicator's visual response is correlated with the response characteristics of any one of a wide range of specific host products including foods, drugs and vaccines, industrial and other products whose quality is related to condition-exposure over time. The system includes a historical record with one or more historical visual indications of past cumulative exposures. An airline meal can be accompanied by a novel freshness certification document which can simulate a travel document and provide, in a graphically appealing manner, a verified indication of the freshness of the meal served. Also disclosed are a novel quality assurance document and method and a cold chain monitor.

Abstract: A system for recovering a diacetylenic monomer shelf life monitoring compound of reduced particle size and narrow size distribution range which comprises quenching a solution of the monomer by mixing the solution in a lower temperature quenching fluid having a base temperature which is at least about 30° C. below the nominal temperature at which the monomer compound recrystallizes from solution, the mixing being effected in such a manner as to limit the resulting quenching mixture temperature to one which is not higher than a maximum of about 15° C. above the quenching fluid base temperature.

Abstract: Precipitation of polyacetylenic agents can be effected with control of a particle size parameter such as mean size or spread, by mixing a warm solution of the acetylenic agent with a cold precipitation fluid and appropriate selection of a constituent of the cold precipitation fluid and/or of the temperature conditions and collecting the precipitated acetylenic agent. Precipitation additives such as nitrocellulose or gelatin can usefully be employed. Solvents such as aqueous methanol and ethyl 3-ethoxypropionate can be useful. Polyacetylenic agents, e.g. substituted diacetylenics are useful to provide visual changes in condition-monitoring indicators such as time-temperature indicators, “TTIs”, useful as freshness indicators for radiation exposure monitoring and for other purposes. Controlled, small and/or consistent particle sizes of such polyacetylenic agents are helpful in providing consistent commercial properties, especially in inks in which they may be formulated.

Abstract: A product shelf life monitoring system comprising an active substituted diacetylenic monomer component indicator composition is responsive to an integral of varying temperature over time to effect a solid state polymerization in the active monomer which results in a visible change in color density or the like at a rate designed to closely approximate the degradation, or shelf life, of an associated foodstuff or medicament product. The reactivity of the monomer component upon which the time-temperature integral of the indicator composition, and thus the represented shelf life, primarily depends may be readily varied by refluxing a solution of the monomer in a selected solvent for a predetermined time prior to recrystallization of the monomer for incorporation into the indicator composition.