Abstract: A dispenser box having a modified rectangular shape with leaf-shaped end walls and partly curved main walls that may form symmetrically or non-symmetrically configured halves of the dispenser box. The first main wall has a substantially flat surface extending from a first side edge of the dispenser box and changing into a curved surface when moving in a direction from the first side edge towards a second side edge of the dispenser box. The second main wall has a corresponding substantially flat surface at the second side edge, which changes into a curved surface when moving in a direction towards the first side edge.

Abstract: The present invention relates to a system for providing food expiration date information using a TTI (time temperature integrator) and a method for providing food expiration date information using the same. The system for providing the food expiration date information and the method for providing the food expiration date information using the same of the present invention includes: an input unit for receiving TTI information, food information, and distribution history information; a calculation unit for producing a TTI indication value corresponding to an expiration date of the food; and an output unit which determines and outputs a color corresponding to the expiration date of the food among stages of colors which can be expressed through the TTI according to time and temperature conditions using the TTI indication value.

Abstract: The present invention relates to a time temperature indicator comprising at least one indicator compound in a first isomeric form, which is converted into a second isomeric form of said indicator compound in a valence isomerization reaction without migration of an atom or chemical group attached to said indicator compound in a time and temperature dependent manner, wherein the formation of the second isomeric form is detectable by monitoring a physical characteristic of the indicator. The present invention also relates to a method of manufacturing such a time-temperature indicator comprising the steps of (a) embedding in or atop a matrix said indicator compound; and (b) inducing the formation of a metastable state of said embedded indicator compound.

Abstract: The subject matter described herein relates to thermoresponsive switching materials that undergo a thermal transition over a narrow temperature range and to devices, such as actuators, indicators, and sensors, prepared from such compositions.

Abstract: A packaging nexus that drives a predetermined message to facilitate a consumer message is described. The nexus formed from the one or more components of the packaging assembly is configured to collectively signal and/or reinforce a predetermined message and at least partially facilitate a consumer impression.

Abstract: In today's lifestyle it is not always practical to be able to prepare foodstuff on a freshly prepared basis. Therefore partial cooking of foodstuff and preparation for heating and completion of cooking is used. An apparatus, a container and methods thereof for heating foodstuff at the home environment provides a solution for preparation of restaurant quality foodstuff. The apparatus, containing water, is adapted to accept the container that contains the foodstuff, where the water temperature is set to a desired temperature that is appropriate for the foodstuff. The container is left within the apparatus for the appropriate amount of time before removal from the apparatus, extracted from the container and served as high quality foodstuff to the table. The container may be used with or without the apparatus and have means to enable handling of the foodstuff in warm to hot water as may be necessary and providing feedback thereof.

Abstract: A heat-in package with doneness indicator for heating applications, such as microwave heating of foods or sterilization applications. The doneness indicator comprises indicia printed with thermochromatic ink on the heat-in packaging. The doneness indicator can be sealed from front to back on the heat-in packaging in such a way that the heat transfer to the sealed area is controlled so that the contents contained within the heat-in packaging has adequate time to heat before a color change or other visual transformation is observed in the doneness indicator. Furthermore, the sealed area containing the thermochromatic ink is not in direct contact with the contents within the packaging. The ink changes due to heat conduction through the film. A venting system can further be incorporated to prevent excessive pressure build-up within the packaging.

Abstract: Ingestible compositions comprising a chromic change agent together with methods of making and using them are provided. The chromic change agent alternatively may be associated with the ingestible, such as a packaging material for the ingestible. In response to a triggering event, physical or chemical, the chromic change agent changes color to provide information as to the history of the ingestible, either prior or contemporaneous with use. Depending on the use, the color change agent may be reversible or irreversible. Various solid or liquid ingestible compositions are provided for determining ingestible temperature, storage temperature, user temperature, light exposure, pH change, hydration or solvation change, mechanical stress, and the like, particularly in comestibles. Of particular interest are polydiacetylene polymers that may be formulated to provide compositions having numerous different color transition triggering mechanisms.

Abstract: A food emulator for the production of an edible article that can substitute for a food item and that includes a carrier element formed of an edible material and an information element disposed on one or more surface of the carrier element. The one or more information element includes information related to the food item. The information may be one or more of a flavoring agent, a coloring agent or a texturing agent, for example. Different types and combinations of information may be provided by way of the information element and/or the carrier element to substitute for food items.

Abstract: A device for monitoring the expiration of goods includes a substrate and an unreacted composition affixed thereto which is intrinsically reactive to one or both of its thermal environment and the length of time following activation. The reactivity results in a color formation of the composition with the color formation being a single color upon reaction to one of said thermal environment or length of time and multiple colors upon reaction to both. The device may be a label affixed to a container containing the goods to be monitored or may be printed directly on a container.

Abstract: A method of operating a microwave oven to determine the correct cooking time for a food item placed within the oven. A food package having a thermochromic element which changes color over a predetermined temperature range is placed in the microwave oven. Microwave energy is supplied into the oven. The food package is rotated within the oven cavity and the color of the thermochromic element is monitored as it rotates past an opto-electronic device or detector capable of detecting the color changes of the thermochromic element such that a plurality of signal pulses are generated having a value corresponding to the color of the element. The supply of microwave energy into the oven is terminated when the rate of change between successive pulses decrease to a predetermined value.

Abstract: A device is provided for temperature controlled heating of primarily solid food in a microwave oven, which includes a block of polymeric material which is thermally insulated with respect to the food and which is provided so as to be exposed to a same microwave radiation as the food. A heat sensitive, readable marking which corresponds to a temperature of the food is provided on a surface of the block of polymeric material. A reader is connected to a heating system of the oven, and reads the marking and transmits control signals to a control circuit for controlling the heating system of the oven, when the reader reads a change of the marking.

Abstract: An edible product such as a unit dosage form of a pharmaceutically active substance includes a layer of a material that can receive and retain a high resolution microrelief that can convey information. The microrelief is themo-formable, preferably formed from an aqueous solution of HPMC and/or HPC plus a plasticizer and colorant. Other additives such as strengtheners, surfactants and adherents may be used depending on the application. The materials are selected and proportioned to control the fading or change in color of the visual image or effect produced by the relief to indicate exposure to an unacceptable degree of heat or humidity. The dosage form can be the relief-containing layer itself with the pharmaceutical carried therein. In a preferred form, the layer is an outer coating over a core containing the pharmaceutically active substance. Coated tablets are configured to resist twinning.

Abstract: A device for monitoring the expiration of goods includes a substrate and an unreacted composition affixed thereto which is intrinsically reactive to one or both of its thermal environment and the length of time following activation. The reactivity results in a color formation of the composition with the color formation being a single color upon reaction to one of said thermal environment or length of time and multiple colors upon reaction to both. The device may be a label affixed to a container containing the goods to be monitored or may be printed directly on a container.

Abstract: A method of verifying the usability of a photosensitive film product just prior to use by applying at least one environmental sensitive label to the photosensitive film product. The environmental sensitive label has at least one cumulative time-temperature indicator and at least one thermal event indicator each providing independent indications of product performance in a predetermined environment.

Abstract: A comparator for use with a time-temperature indicator wherein the time-temperature indicator includes an active portion having an initial color and which undergoes chemical changes as time elapses and at a rate related to the temperature of the surrounding environment and wherein the chemical changes produce changes in the color of the active portion. The comparator comprises a substantially planar support member, and a plurality of comparator stages located on the support member. Each comparator stage comprises a first portion having a reference color and a second portion having a predetermined color that is the same as one of the colors to which the active portion of the time-temperature indicator changes.

Abstract: A device composed of (1) a color changing indicator, (2) an optional polymeric binder, preferably having gel forming capability, and (3) an activator solvent system which induces a color change in the indicator when device is frozen, in the region of about 0 to −30° C. An example of the device is an indicator of a fine dispersion of partially polymerized diacetylene of the formula: R—C═C—C═C—R, where R is a substituent group, e.g., 4BCMU where R=—(CH2)OCONHCH2COO(CH2)4H, dispersed in a mixture of solvents, e.g., 96:4 water:ED (ethylene glycol diacetate), with or without a polymeric binder. When the temperature of the device is lowered to the freezing point of water, the activator solvent phase separates out of the mixture and induces a color change in the indicator. The device can undergo an irreversible color change, e.g., from blue to red, when the activator mixture is frozen in the region of about 0 to 30° C.

Abstract: A frozen ice confection of fixed shape is described which has its opacity controlled in relation of the temperature of the confection. The confection may also have an imbedded indicia which becomes view able as the transparency of this frozen confection increases.

Abstract: A shielding method for achieving highly uniform temperatures in liquids during microwave heating by substantially enhancing vertical mixing currents in said liquids, making determinations of final temperature reached in said liquids either by touch or the use of a temperature indicator efficacious, comprising: a electrically conductive shield having very low impedance at microwave frequencies; having, a generally cylindrical shape, and dimensions chosen to accommodate a variety of microwaveable containers. said shield: to be concentric with a microwaveable container, containing a liquid to be heated by microwave radiation; and, to be located so as the top edge of said shield is at or above a vertical level corresponding to the level of the liquid in said container; and, to be of sufficient height as to cover at least 10% of the height of the liquid in said container.

Abstract: Temperature control is carried out with a temperature control material comprising a temperature indicator whose developed color density differs according to temperature, which is irreversible at environmental temperature, which changes its color according to crystal or non-crystal, or phase separation or non-phase separation, and whose glass transition temperature is set to a temperature higher than control temperature, by irradiating the temperature indicator with light having a wavelength absorbed by a color developed by the temperature indicator and detecting the intensity of the reflected light or transmitted light. Accordingly, even when the temperature becomes higher than control temperature temporarily, temperature control can be carried out smoothly thereafter.

Abstract: A defrosting indicator for frozen foods is made from a piece of transparent tape and a layer or multiple layers of absorbent material. The indicator also includes a segment of a frozen ink cartridge of the kind used in ball point pens. The absorbent material is placed on top of the adhesive side of the tape with the frozen segment placed on top of the absorbent material. The tape and absorbent material are then folded over with the frozen ink segments in between the absorbent material. The edges of the tape are sealed together and the indicator placed on a container of frozen food.

Abstract: A method of manufacturing a product, and a product, in which a logo and/or trademark of a sports team, league or association is applied to the food product. The method of applying the logo and/or trademark includes ink jet printing, or printing with a roller or plate with an edible coating, or branding with a hot grill element.

Abstract: This invention relates to the technical field of culinary arts. It includes an amusing way of presenting a novelty item such as a figurine or other promotional or warning message during the heating of a microwave food package which may also serve as a food ready indicator. It may be used as a retrofit to a food package or integrated into a food package.

Abstract: A shielding method for achieving highly uniform temperatures in liquids during microwave heating by substantially enhancing vertical mixing currents in said liquids, making determinations of final temperature reached in said liquids either by touch or the use of a temperature indicator efficacious, comprising: a electrically conductive shield having very low impedance at microwave frequencies; having, a generally cylindrical shape, and dimensions chosen to accommodate a variety of microwaveable containers. said shield: to be concentric with a microwaveable container, containing a liquid to be heated by microwave radiation; and, to be located so as the top edge of said shield is at or above a vertical level corresponding to the level of the liquid in said container; and, to be of sufficient height as to cover at least 10% of the height of the liquid in said container. 2.

Abstract: A filter for the adsorption of ingredients from and/or the dispersion of ingredients into a fluid includes a matrix which has a plurality of particles having an inherently active surface or an active surface made of a fluid treating material. The particles are held in place by a moderately viscous binder which is impervious to the flow of the fluid. The particles, however, are made of a fluid pervious material. An insufficient amount of binder is incorporated in the matrix to otherwise completely cover the particles. Thus portions of the active surface of the particles remains exposed to the flow of fluid thereby resulting in tortuous paths of flow through the matrix, thereby assuring contact with the treating particles.

Abstract: Time and temperature integrating devices for providing a visually observable indication of cumulative thermal exposure are disclosed comprising (a) a substrate having thereon a thermally sensitive image-forming area comprising a combination of (i) an organic silver salt oxidizing agent and (ii) a reducing agent for the organic silver salt oxidizing agent, and (b) indicating indicia in association with the image forming area for indicating when the device has been exposed to a predetermined cumulative thermal exposure. In accordance with further embodiments of the invention, a process of applying such a device to a perishable product, and a perishable product having such a device applied directly thereto or to packaging thereof, are also disclosed. Time-temperature indicators in accordance with the invention undergo readily detectable changes can be easily optimized to match various rates of time-temperature dependent cumulative changes desired to be monitored for various products.

Abstract: An oven and a vessel having a food-stuff or beverage in it cooperate to provide optimum operation of the oven to cook or heat the food-stuff or beverage. The vessel is dimensioned to fit within the oven and has an information carrier for indicating the temperature of the food-stuff or beverage within the vessel by changing color, and a separate identification marking. A detector within the oven detects the identification marking and activates a control device for the oven if at least one predetermined identification requisite from the identification marking is met. The identification marking preferably is a hologram which may be visible, or invisible, to the naked human eye. A separate non-temperature sensitive mark may be provided on the vessel and is sensed by a separate sensing device to allow the oven to start operation.

Abstract: An indicator including an indicator product that is adapted to change visual appearance, an indicator scale in near adjacency to the indicator product including substantially all of the visual appearances that the indicator product can display and a binary scale in near adjacency with the indicator product and the indicator scale. A package adapted to contain a product is also disclosed including a container for holding the product with an indicator secured to the container. Associated methods of (i) determining whether a product in a package is acceptable; (ii) packaging a product; and (iii) making an indicator label are also disclosed.

Abstract: A container sensing system for controlling the heating in a microwave oven of a container carrying control information which may be read by an optical reading device. The optical reading device includes a light transmitter and a light receiver for sensing a reflectance of a sensor. The sensor includes a first and second region. The first region is provided for establishing a start and non-start condition while the second region is provided for reading temperature information. To avoid the surface reflected portion of incident light to gain an accurate reading, the axes of transmission and reception are offset in the same angular direction to a perpendicular of a sensor surface wherein the transmitter directs an inclined reading light beam onto a region of the sensor and the receiver receives the scattered light therefrom depending on the reflection properties of the sensor region.

Abstract: A method for controlling a heating procedure in an oven by using an optically readable information carrier with or on the heating object. The oven may be provided with an optical reading device for touchless reading of the information carrier before and/or during the heating. By providing the information carrier with one or more fields that exhibit color shift at temperatures at will, a feed-back control of the procedure is made possible with simple technical solutions. The special feature of the method is the use of an additional information field for control of the start of the oven.

Abstract: A filter is formed from a laminate of two sheets having a layer of adsorbent material and a layer of flavor enhancing material in the form of a flavor or supplement layer sandwiched between the sheets. Preferably, the adsorbent layer and the flavor or supplement layer are applied by a printing process.

Abstract: A sensor permanently indicates that it has been exposed to temperatures exceeding a critical temperature for a predetermined time period. An element of the sensor made from shape memory alloy changes shape when exposed, even temporarily, to temperatures above the Austenitic temperature of the shape memory alloy. The shape change of the SMA element causes the sensor to change between two readily distinguishable states.

Abstract: A thaw indicator unit for sensing and permanently recording a thawing event experienced by a temperature sensitive food or other item, the unit having a container of transparent, non-toxic material, and having a hermetically sealed chamber containing a frozen color change medium having at least two segments of differently colored frozen aqueous compositions, the segments being juxtaposed along an interface of molecular thickness, and at least one of the segments being substantially homogeneously colored differently from at least one juxtaposed other colored segment, wherein the colorants are food grade materials, and whereby the unit when placed on, in or in close proximity to the item will record any first thawing event by way of thawing of the juxtaposed segments and intermixing thereof at least at the interface thereof to produce at least a visible section of an intermix of said compositions and having a markedly different and readily visible color from that of the juxtaposed segments.

Abstract: A time-temperature monitor is provided that is adapted for indicating the amount of accumulated time during which the ambient temperature adjacent to the monitor is above a predetermined temperature. The time-temperature monitor comprises a viscous, non-Newtonian fluid biased within a flow path defining element, with the rate of flow therethrough being regulated by a constricting orifice disposed in a nozzle that is positioned in fluid communication with the flow path defining element.

Abstract: A device for indicating a time-temperature thermal history of a refrigerated product over a specific temperature range. The device includes a container having a high-viscosity fluid therein, the fluid remaining in either a liquid or gaseous state over the entire specific temperature range. A mobile portion moves within the fluid as a result of a return force of an elastic component. The displacement of the mobile portion indicates the time-temperature thermal history of the product over the specific temperature range.

Abstract: There is presented an indicator capsule for determining temperature and t exposure required for food processing comprising a cylindrical tube having a closed end and an open end, a cap for connection to and removal from the open end to close and open the tube, and a solution in the tube which is reactive to accumulated temperature and time exposure to fluoresce proportionally to the accumulated temperature and time exposure. There is further presented an indicator system for determining temperature and time exposure required for food processing including the above capsule, a pipetting device for removing the solution from the capsule, and a spectrofluorometer for indicating the fluorescence of the solution. There is still further presented an indicator capsule wherein the solution comprises bacterial spores; a system including the capsule, a pipetting device, and an agar plate for providing a count of the surviving spores to, in turn, provide an indication of the aggregate thermal effect on the solution.

Abstract: An apparatus for checking deep-frozen food, which irreversibly indicates if an additional storage temperature has been exceeded, is described. A flat plastic bag having transparent walls, into which eutectic mixture having a liquid/solid phase transition in the range from 0.degree. to -50.degree. C. has been introduced, together with a magnetic dispersion consisting of finely divided magnetic pigments, has a heat-conducting connection to the material to be frozen. A magnetic stripe which contains a magnetically recorded pattern and which remains connected to the bag until the indicating apparatus together with the material to be frozen has been cooled below the limiting temperature is stuck to the bag. The magnetic stripe is then removed. If the permissible limiting temperature is exceeded, the optically or magnetically readable structure produced by the magnetic stripe in the indicator bag is eliminated, permitting easy checking of the deep-frozen food.

Abstract: A process for controlling the microwave heating of a product to a temperature which is higher than or equal to a determined temperature for a period which is longer than or equal to a determined period, a marking support and a receptacle for product intended for such a control. Measurement is made of the resistivity of a thermally crosslinkable ink filled with conductive particles, with which the product or the receptacle containing the product has been previously marked and the resistivity of which is arranged to decrease in a predetermined manner in relation to the temperature and the period of microwave heating. The invention is applicable especially to the control of the sterilization of a pharmaceutical or agri-foodstuff product.

Abstract: Temperature indicator for refrigerated products operating on the principal of solidification and melting of liquid bodies at room temperature is provided with a transparent envelope containing a capsule filled with an aqueous solution which is liquid at room temperature. The capsule includes a fracture point causing it to split into two parts due to solidification of the solution, and further includes a compressed spring positioned so that when the capsule is fractured, the spring remains compressed as long as the solution is in the solid state, and visibly and irreversibly separates the two parts of the capsule if the solution turns to a liquid. The monitoring device serves to verify that the temperature is maintained either between two limits or below or above a critical temperature.

Abstract: Packaging apparatus and method, for use in controlled atmosphere packaging of horticultural produce in controlled permeability film. A valve apparatus mounted on or in a packaging film including a temperature sensitive sensor formed from a bimetallic or shape-memory material (2), or a chemical sensitive sensor formed from a swellable polymer, to actuate the valve member (pin or plug) (1) on, or in communication with the sensor. In use, after sealing the produce within the packaging film, the valve apparatus opens the packaging film in response to a temperature change of predetermined magnitude to allow oxygen flow for extension of storage life or fumigation of the produce.

Abstract: In the heat-sensitive indicator herein disclosed, a colored heat-fusible substance 3 is accommodated in an inner hollow portion of a projection 1 which is formed from a film collapsible by application of an external pressure such as a finger-pressure. The opening of the hollow portion is sealed with a thin cover 9 collapsible through the application of the foregoing pressure. An An absorber 7 in which the colored heat-fusible substance 3 in the molten state can permeate is arranged outside the thin cover 9 of the hollow portion. The colored heat-fusible substance 3 is supported by a carrier 5 and accommodated in the interior of the hollow portion of the projection 1. A space in which the carrier is dropped when the thin cover 9 is broken through the application of a pressure is formed, behind the thin cover 9, by a hollow ring 11.

Abstract: A process for the production of an indicator for monitoring the temperature of a cooled or deep-frozen product, such as packaged foodstuffs, pharmaceuticals and the like, is provided, which indicator shows that a predetermined critical temperature of the cooled or deep-frozen product has been exceeded. An easily applicable and economically made indicator is produced by casting a substance which is fluid or semifluid above the critical temperature into a specific geometrical shape and then cooling the substance below the critical temperature until it assumes a solid form. The critical temperature may in this connection lie above or below 0 degrees Centigrade.

Abstract: An indicator composition and process capable of changing color in relationship to its exposure to a temperature above and below a base line temperature and to the time of said exposure, for monitoring the time-temperature history of a substrate, depositable as a layer on said substrate, comprising a dispersion of either a binder comprising a reaction inert, neutral finely divided absorbent, in the presence of a reactant comprising a salt of an acid or an organic compound substituted by at least one moiety which, in ionic form, is an anion or a binder/reactant, comprising at least one solid organic polymer whose constituent units contain, as a covalent substituent, at least one moiety which, in ionic form, is an anion; as indicator, at least one acid sensitive pH dye and as activator, at least one base. This composition and process may be utilized to form a solid state device for monitoring integral values of time and temperature during storage of perishables.

Abstract: A freeze indicator comprising a frangible ampule containing a liquid which expands upon freezing, a dye soluble in the liquid and a nucleating agent, the nucleating agent and the liquid having substantially similar space groupings, the ampule being enclosed within a blister of transparent film, the blister being adhered to a backing, the inner surface of the blister being coating with an absorbent layer comprising a binder wettable by the liquid and a filler, whereby upon rupture of the ampule the liquid containing dye is absorbed by the absorbent layer thereby causing a color change in the absorbent layer visible through the transparent film.

Abstract: A new and improved integrating indicator system operable to signal the attainment of one or more preselected time-temperature integrals which monitor the temperature and time history of a product utilizes a dual system of specific reaction pairs which simultaneously generate acid and alkali from two neutral substrates. One of the substrates is present in excess of the other. The preferred dynamic indicator system generates a constant pH buffer in the alkali range that is maintained until one of the substrates is depleted. At that time, a rapid pH change in the indicator solution to the acid range occurs, resulting in a very sharp visual color change in a pH-sensitive dye. In preferred embodiments, the specific reaction pairs are enzyme/substrate pairs, preferably urease/urea and yeast/triacetin.

Abstract: Liquid and/or temperature activated elaspsed time sensors suitable, in particular, for use as doneness indicators for foodstuffs and for other purposes. The liquid activated indicators include a porous structure which generates a first color by effects which include optical interference when pores of the structure are gas-filled, and a second contrasting color when the pores of the structure are liquid filled. The porous structure is covered with a transparent or translucent cover which is unattached in certain areas to allow for capillary movement of liquid between the cover and the porous structure. An entrance permits liquid to enter between the cover and the porous structure. When contacted with liqiuid, the liquid is drawn into the device and produces an expanding area of contrasting color which is used to indicate the elapse of time.

Abstract: A method of making and using a liquid crystal cumulative dosimeter container including a resilient outer body sealed to confine a first liquid crystal composition constituent and a second liquid crystal composition constituent and having at least one transparent section to permit observation of the color of the confined composition, and a barrier contained completely within and physically unattached to the outer body for separating the first constituent from the second constituent, whereby disruption of the barrier allows the first constituent to mix with the seocnd constituent. The barrier is formed either by encapsulating one or both of the constituents or by using air bubbles.

Abstract: A temperature sensing element comprises a heat-shrinking film and a fixing means for fixing the heat-shrinking film to an article to be monitored such as a food vessel. The element indicates that the content of the food vessel being heated by a microwave oven reached a given temperature range.

Abstract: The present invention provides a process for the determination of fructosamine in body fluids using as a standard, a solution which contains a peptide or protein, the amino acid units of which consist of at least 25% of lysine and/or ornithine and is present in glycosylated form.The present invention also provides a standard solution for the determination of fructosamine containing a peptide or protein, the amino acid unit content of which consists of at least 25% lysine and/or ornithine and is present in glycosylated form, and a method of calibrating such a standard solution.

Abstract: An improved steam sterilization indicator is provided. The indicator includes a fusible material in tablet form, deposited in an embossment in one end of a thin aluminum backing. A wicking strip is attached to the backing with one end of the strip being in close proximity to the fusible tablet. A clear plastic material covers the tablet and the strip and is adhered to the backing. The melting point of the fusible tablet is depressed in the presence of saturated steam. Upon melt, the material in the tablet is absorbed by the wicking strip, producing a color front to provide an indication of the integration of time and temperature in the presence of steam. Various amounts of a binder are used in the tablet to provide a device which may be adjusted to reflect the thermal death curves of various types of microorganisms. The cover and the wick are bonded to the backing by an acyclic adhesive which also affects the rate of the indicator.