106 results about "Time temperature indicator" patented technology

A time-temperature indicator label for measuring the length of time to which a product has been exposed to a temperature above a pre-determined temperature is provided. The period of time of exposure is integrated with the temperature to which the indicator is exposed. The label is a composite of a plurality of layers adapted to be adhered at its underside to a product container. The label includes a printable surface layer, a longitudinal wicking strip that is adhered underneath the surface layer substantially at the opposite extremities only of the wicking strip and a lower substrate layer forming an envelope with said surface layer. A heat-fusible substance, which melts and flows above a pre-determined temperature, is applied on the surface of the wicking strip contiguous to at least one of the ends of the wicking member. When the heat-fusible substance is exposed to a temperature above the pre-determined temperature, the heat-fusible substance flows along the length of the wicking member. The label has a printable surface layer and is sealed at its peripheral edge to the peripheral edge of the substrate layer. These layers encapsulate the wicking member and the heat-fusible substance. The surface layer is provided with a sight window at an intermediate location over the wicking member through which the progress of flow on the wicking member is observed.

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.

A full-history time-temperature indicator system which is capable of exhibiting a time-temperature dependent and visually detectable chemical reaction, useful for monitoring the time and temperature exposure of food products. The system comprises an immobilized reactant, such as Fe³⁺, and a mobile reactant, such as Fe(CN)₆^4-, initially contained in separate compartments, and separated by a sealing. The system is activated by removing a sealing between the compartments whereby the mobile reactant in a time-temperature dependent manner is brought into contact with the immobilized reactant resulting in a visually detectable reaction signal.

This invention covers improved electronic time-temperature indicators with a visual output, and other devices and methods by which the thermal history of a complex material, which may not obey a simple exponential Arrhenius law degradation equation, may be monitored, and the subsequent fitness for use of the tracked material may be quickly ascertained. In particular, the invention discloses a rapidly reprogrammable electronic time-temperature tag that may be easily customized with the thermal time-temperature stability profile of an arbitrary material, using electronic data transfer methods. Using this device, a single, low-cost, generic time-temperature tag may be mass-produced, and then subsequently programmed to mimic the stability characteristics of nearly any material of interest.

This invention covers improved electronic time-temperature indicators with an RFID output, and other devices and methods by which the thermal history of a complex material, which may not obey a simple exponential Arrhenius law degradation equation, may be monitored, and the subsequent fitness for use of the tracked material may be quickly ascertained. In particular, the invention discloses a rapidly reprogrammable electronic time-temperature RFID tag that may be easily customized with the thermal time-temperature stability profile of an arbitrary material, using electronic data transfer methods. Using this device, a single, low-cost, generic time-temperature tag may be mass-produced, and then subsequently programmed to mimic the stability characteristics of nearly any material of interest. By utilizing data compression to compress a material's extensive thermal history into the small user data field transmitted by modern RFID tags, a considerable amount of information relating to product status and cause of failure may be rapidly transmitted within the small memory confines of standard RFID tag protocols.

The invention is a modified atmosphere package comprising about 0.1 to 5 vol. % carbon monoxide and that includes a time-temperature indicator that is disposed in a temperature monitoring relationship with the package and that is configured to indicate whether a perishable product disposed in the package has been exposed to a time-temperature exposure that may have caused spoilage of the product. The time-temperature indicator may be used to alert a person that a red meat product disposed in the package has potentially spoiled even though the meat product may have a fresh “bloomed” appearance. As a result, the possibility of a consumer purchasing a spoiled product may be reduced. The invention is also directed to a method of using the time-temperature indicator to indicate the likelihood of spoilage in the packaged product. In one embodiment, the time-temperature indicator changes visual appearance based on a combination of predetermined times and temperatures.

The invention discloses a time temperature indicator and a manufacturing method thereof. The time temperature indicator comprises a substrate layer, a bonding layer, an indication layer, a phase-change material and a blocking layer, wherein part of the indication layer forms a convex hull, and the convex hull is provided with a storage room; the indication layer comprises at least two interlayers and a sandwich layer arranged between the two interlayers, the interlayer between the sandwich layer and the bonding layer is a dense film layer, a notch passing through the sandwich layer is arranged on the dense film layer, and a liquid channel is communicated between the storage room and the notch; the phase-change material is located in the storage room, and the blocking layer is arranged between the phase-change material and the notch; and the liquid phase-change material can press the blocking layer broken under effects of an external force to enter the liquid channel and be penetrated in the sandwich layer through the notch, and the penetration length to the time length of the liquid phase-change material on the sandwich layer is in direct proportion. Due to the time temperature indicator of the invention, the liquid phase-change material can be prevented from passing through the interlayers to be penetrated in the sandwich layer.

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.

A system and method for indication of temperature exposures beyond a set of predetermined limits employs the salts of weak acid-strong base or of a strong acid-weak base compound as reactants. A device includes a housing and capsule. A first reactant and a liquid are included within the capsule. The liquid is chosen such that it expands upon freezing. The capsule is sized such that when the liquid freezes and expands, the capsule fractures. A second reactant is provided within the housing. The location of the second reactant and the method of attaching (if any) the second reactant to the housing may take various forms. When the liquid within the capsule freezes, it expands and fractures the capsule. Upon thawing, the reactant within the capsule escapes and mixes with the reactant located outside the capsule. A second embodiment is a time-temperature indicator. A flexible housing is used, allowing the user to manually deform the housing to fracture a capsule enclosed therein. The reactants combine to produce a color. The color is chosen to be a different color than the housing, allowing a person viewing the indicator device to quickly and easily determine the status of the object being monitored. The threshold temperature at which the device will indicate a changed condition may be varied. Exemplary temperatures include below the freezing temperature, at the freezing temperature, and above the freezing temperature. The capsule composition may be varied such that it melts at a predetermined temperature. Thus, the device may also be used to indicate whether a high temperature has been met or exceeded.

The invention discloses a time-temperature indicator. The time-temperature indicator disclosed by the invention comprises a back coating, a paper base, a bottoming layer, an indicating layer and a protective layer, wherein the back coating is arranged at one side of the paper base; and the bottoming layer, the indicating layer and the protective layer are sequentially arranged at the other side of the paper base. The invention also discloses a preparation method of the time-temperature indicator. The time-temperature indicator disclosed by the invention can be better applied to monitoring thequality change of storage-resistant food.

A visual thermal history indicator comprising a pattern produced from at least two waxes wherein one wax has a melting point that differs from the other wax, or where the waxes have the same melting point but different melt flow behaviour, and wherein the pattern is adapted so that when the lower melting point wax melts or the wax with greater melt flow behaviour flows, the visual appearance of the pattern changes, and wherein when the second and subsequent higher melting waxes melt, or when the lower melt flow behaviour waxes flow, the visual appearance of the pattern changes as each wax melts or flows.

Time temperature indicators are disclosed which comprise at least one carrier material and one aggregachromic indicator dye and which respond to the combined effects of temperature and time with an easily measurable, time-temperature dependent, irreversible, color change. The invention also discloses to methods to produce such time-temperature indicators and materials therefore. Also, the devices disclose methods for determining the time/temperature history.

A device and method of making a device for indicating a change in condition is disclosed. A first embodiment is a device for indicating a transition from a frozen condition to a thawed condition is disclosed. The device includes a housing and a capsule. A first reactant and a liquid are included within the capsule. The liquid is chosen such that it expands upon freezing. The capsule is sized such that when the liquid freezes and expands, the capsule fractures. A second reactant is provided within the housing. The location of the second reactant and the method of attaching (if any) the second reactant to the housing may take various forms. When the liquid within the capsule freezes, it expands and fractures the capsule. Upon thawing, the reactant within the capsule escapes and mixes with the reactant located outside the capsule. A second embodiment is a time-temperature indicator. A flexible housing is used, allowing the user to manually deform the housing to fracture a capsule enclosed therein. The reactants combine to produce a color. The color is chosen to be a different color than the housing, allowing a person viewing the indicator device to quickly and easily determine the status of the object being monitored. The threshold temperature at which the device will indicate a changed condition may be varied. Exemplary temperatures include below the freezing temperature, at the freezing temperature, and above the freezing temperature. The capsule composition may be varied such that it melts at a predetermined temperature. Thus, the device may also be used to indicated whether a high temperature has been met or exceeded.

The present invention relates to a time-temperature indicator for monitoring the quality state of a thermally sensitive article and a monitoring method. The present invention also relates to a preparation method of the time-temperature indicator and a thermally sensitive article using the time-temperature indicator. The time-temperature indicator according to the present invention comprises two laminated layers which are physically separated, i.e. a function indication layer and an adsorption function layer. The two laminated layers are stored and transported separately, and combined together in use. Therefore, the time-temperature indicator of the present invention can be stored and transported at room temperature, which reduces the usage costs of the time-temperature indicator.

The invention discloses a diffusible time-temperature indicator, an indicator card and a preparation method thereof, wherein the time-temperature indicator consists of methyl salicylate, gamma-caprolactone and a coloring agent, and the volume ratio of the methyl salicylate to the gamma-caprolactone is 40: (1-5). The time-temperature indicator card adopts the mixture of the methyl salicylate and the gamma-caprolactone as a diffusible substance, the coloring agent is further added, the indicator is prepared by fully mixing, then the solidified state is formed by ultra-low temperature processing, and the solidified indicator is in contact with the diffusible medium for preparing the indicator card. The time-temperature indicator card can change the mixing ratio of the methyl salicylate and the gamma-caprolactone, realize the regulation of the critical temperature of the indicator, be applicable to the needs of different frozen foods and have a wide range of applications.

Provided is a saccharifying enzyme type time-temperature indicator. Dextrin solution and iodine solution are mixed to form mixing solution, the mixing solution and saccharifying enzyme liquid are independently packaged, and the mixing solution and the saccharifying enzyme liquid are mixed when in use. The purposes of indicating storage temperature and time are achieved by utilizing hydrolysis reaction of saccharifying enzyme and dextrin, using the iodine solution as indicating agents and displaying cumulative effects of time and temperature through color changes. The time-temperature indicator is stable in reaction system, obvious in color showing effect, low in cost and easy to practically apply.