Abstract: An electrical temperature sensor (10) comprises a liquid crystalline material (12). First and second electrically conductive contacts (14), (16), having a spaced relationship therebetween, contact the liquid crystalline material (12). An electric property measuring device is electrically connected to the first and second contacts (14), (16) and is arranged to measure an electric property of the liquid crystalline material (12). The liquid crystalline material (12) has a transition temperature T at which it undergoes a phase change between polar and non-polar phases. The phase change between polar and non-polar phases causes a change in said electric property of the liquid crystalline material (12).

Abstract: A method comprising injection molding a plastic part from a polymer formulation comprising an injection moldable thermoplastic and an additive, wherein the additive has a decomposition temperature that establishes a maximum processing temperature for the polymer formulation. The additive will thermally decompose to generate gaseous products causing visible bubble formation in the surface of the plastic part in response to exposure to a processing temperature that exceeds the decomposition temperature of the additive. A suitable additive may be, for example, selected from oxalates, carbamic acids, carbonic acids, diazocarbonyl compounds, and combinations thereof.

Abstract: A method comprising injection molding a plastic part from a polymer formulation comprising an injection moldable thermoplastic and a fluorescent compound, wherein the fluorescent compound has a decomposition temperature that establishes a maximum processing temperature for the polymer formulation. The fluorescent compound will thermally decompose to generate gaseous products causing visible bubble formation in the surface of the plastic part in response to exposure to a processing temperature that exceeds the decomposition temperature of the fluorescent compound. If the plastic part was processed without exposure to a processing temperature that exceeds the decomposition temperature of the fluorescent compound, then any fluorescent compound within the plastic part will cause the plastic part to fluoresce in response to exposure to black light. A suitable fluorescent compound may be, for example, selected from oxalates, carbamic acids, carbonic acids, diazocarbonyl compounds, and combinations thereof.

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 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: 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: Disclosed herein is a temperature monitoring system including a circuit board and a thermochromic coating covering at least a portion of the circuit board, wherein the thermochromic coating is capable of indicating a temperature gradient on the circuit board. The thermochromic coating may comprise a color forming leuco dye, an activator, and optionally a deprotecting agent.

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: The invention provides a set of standards for accurately calibrating a vacuum thermogravimetric analyzer (VTGA). The invention solves the problem of calibrating a VTGA by using the actual magnetic transitions and associated transition temperatures, or Curie temperatures, TC's, of a set of standards which can be used in-situ at the location of the sample holder obviating the difficulties associated with indirect methods of calibration. The set of standards permits accurate calibration through sufficiently numerous calibration points over a rather limited low-temperature range for determining vapor pressures of compounds. The set of temperature calibration standards is fabricated from slugs of ferromagnetic material. The composition of the ferromagnetic material in each slug is altered by alloying a ferromagnetic constituent with a non-ferromagnetic constituent to provide a plurality of standards with different Curie temperature over the limited temperature range.

Abstract: The invention provides a method for accurately calibrating a vacuum thermogravimetric analyzer (VTGA). The invention solves the problem of calibrating a VTGA by using the actual magnetic transitions and associated transition temperatures, or Curie temperatures, Tc's, of a set of standards which can be used in-situ at the location of the sample holder obviating the difficulties associated with indirect methods of calibration. The invention encompasses a method of using a set of calibration standards comprised of a plurality of ferromagnetic slugs to provide a temperature calibration for a VTGA. The method permits accurate calibration through sufficiently numerous calibration points over a rather limited low-temperature range for determining vapor pressures of compounds. Through the use of these standards, highly accurate measurements can be made of the vapor pressures of critical hard disk drive compounds, such as lubricants, and corrosion inhibitors, that are crucial to competitive disk drive technology.

Abstract: The present invention is directed to a thermochromic temperature sensitive composition used to detect the prevailing temperature, and particularly, to detect when the temperature is within a particular range. When the temperature is within that range, the composition undergoes a color change that is visible to the observer.

Abstract: A safety label for use with chafing fuel cans capable of providing the user with information about the current physical characteristics of the can, including as they relate to temperature, employing the use of thermochromic materials dispersed within a media such as ink or paint. The thermochromic materials are capable of undergoing a sharp, reversible visible metachromism between the temperatures of −40° C. and 80° C. The method of manufacturing safety labels according to the invention include the steps of applying informational indicia on the safety label, and then covering such indicia with the media containing the thermochromic materials dispersed therein. When the chafing fuel can is ignited, the media with the thermochromic materials visually undergoes a metachromism, rendering the media invisible, thereby revealing the informational indicia applied with the non-thermochromic ink.

Abstract: An irreversible temperature indicating paint comprises 25 wt % to 50 wt % cobalt silicate, 0 wt % to 20 wt % alumino silicate, 0.5 wt % to 5 wt % toluidine red, 25 wt % to 40 wt % acrylic resin and 10 wt % to 20 wt % silicone resin excluding solvent. The solvent comprises a mixture of 80% 1-methoxy-2-propanol and 20% dipropylene glycol monomethyl ether. The irreversible temperature indicating paint has at least five colour changes in the temperature range 1050° C. to 1350° C. A particular irreversible temperature indicating paint comprises 33.8 wt % cobalt silicate, 16.9 wt % alumino silicate, 2 wt % toluidine red, 30.8 wt % acrylic resin and 16.5 wt % silicone resin excluding solvent. The irreversible temperature indicating paint is used to determine the temperatures to which various parts of turbine blades, turbine vanes or other components are subjected in operation of the gas turbine engine.

Abstract: The invention relates to polymer compositions which enable thermooptic control of signal attenuation in the ultraviolet, visible and near infrared (NIR) regions of the electromagnetic spectrum, and devices incorporating such compositions. The compositions are derived from polymer mixtures which exhibit a cloud point phase transition at a temperature in the range of a thermooptically controlled device such as a programmable waveguide attenuator, a programmable neutral density filter, or an optically absorbent switch. An especially preferred embodiment of the invention comprises a mixture of a high molecular weight chlorotrifluoroethylene fluid and a wax with an “ON-state” insertion loss of below 0.1 dB/cm and an extinction ratio of 22 dB/cm in the 1550 nm NIR telecommunication band.

Abstract: Disclosed is a thermochromic microencapsulated pigment which comprises as four essential components (a) an electron-donating chromatic organic compound, (b) an electron-accepting compound, (c) a reaction medium determining the temperatures at which the color reactions of component (a) with component (b) take place, and (d) a color change temperature regulator, the color change temperature regulator (d) comprising one or more compounds selected from the group consisting of esters, alcohols, ketones, acid amides, hydrocarbons, and fatty acids and having a melting point Y (° C.) satisfying the relationship (X+30)° C.≦Y≦200° C., wherein X (° C.) is the melting point of component (c), and the four essential components being microencapsulated.

Abstract: A barrier for halogenated aromatic compounds is provided, especially fluorinated hydrocarbon films useful for containing precise quantities of halogenated aromatic compounds used as thermally sensitive materials in reversible chemical thermometers. A new shape of chemical thermometer is also disclosed.

Abstract: Helical arrays comprising structurally different chiral non-racemic molecules or molecular entities that control the helical sense of the helical array provide a method for temperature measurement with a unique characteristic in that the temperature dependent chiral biases of the competing structurally different chiral non-racemic entities control the helical sense population since these biases differ in their temperature dependence. By varying the composition of the chiral non-racemic entities, the temperature at which the helical sense population is equal and how the helical sense population varies as a function of temperature can be controlled. In this way, competing structurally different non-racemic chiral groups can be varied in their composition so that a helical array can be formed under their effect and be sensitive to temperature over a wide temperature range. In this way a temperature may be preselected so that a chiral optical property can reach a minimum near to zero at this temperature.

Abstract: Composition containing two components, which together show an elevated freezing point and bring about a color change at selected temperatures and method of making the same. Use of the composition to prepare a temperature indicating device by filling the same in a suitable transparent container and with a background in the form of a color, a number or a letter, which facilitates to visually observe the difference in color change.

Abstract: A composition of matter suitable for use in a reversible thermometer is disclosed which comprises a thermally responsive material capable of being supercooled at least for several minutes, and subject to a change in state from a solid to a liquid substantially at a predetermined temperature; means for visually observing the change in state; and a matrix forming material comprising an amorphous organic compound, the matrix forming material being insoluble in the thermally responsive material; whereby the thermally responsive material is dispersed within the matrix forming material, the composition of matter being reversibly responsive to changes in temperature, and remaining in the liquid state for a time sufficient to permit a user of the composition to observe the change in state. The preferred matrix forming material is polyisobutylene, and the preferred thermally responsive material is a solid solution of ortho-chloronitrobenzene and ortho-bromonitrobenzene.

Abstract: A clinical thermometer with maximum function with a non-toxic eutectic Ga alloy as measuring fluid 14 inside a measuring tube 13 which provides adhesion forces larger than the cohesion forces inherent in liquid 14. To reach the maximum function, therefore, the customary Hick'sche constriction is not required any more facilitating production and handling of said clinical thermometer. Furthermore, a special Ga/In/Sn alloy is described, which may be used not only for clinical thermometers but also as a lubricant.

Abstract: A critical temperature indicating device is provided. It includes a microporous membrane, an indicating composition containing less than about 10 wt-% water, and means for containing the microporous membrane and the indicating composition. The indicating composition includes: a primary organic component comprising at least one compound that has a freezing point above the critical temperature and does not spontaneously wet out the microporous membrane at a temperature at least about 30.degree. C. above the critical temperature; a modifying component comprising at least one compound that has a freezing point below the critical temperature; and a wetting component comprising at least one compound that has a freezing point below the critical temperature and is capable of spontaneously wetting out the microporous membrane at about the critical temperature.

Abstract: A process for homogeneously dispersing at least one reactant in a fluid matrix, characterized in that capsules of a first type containing the reactant(s) are prepared with a first encapsulation product and capsules of a second type containing the fluid matrix are prepared with a second encapsulation product which is compatible with the first, these two types of capsules bearing electric charges of opposite polarity, the capsules of the two types are combined by electric attraction and the first and second encapsulation products are removed so as to obtain a composite material consisting of the fluid matrix containing the reactant(s) in homogeneous dispersion form, and products obtained according to this process.

Abstract: A reversible thermochromic composition comprising as essential components (a) an electron-donating color-developing organic compound, (b) at least one electron-accepting compound selected from alkoxyphenol compounds represented by Formula I: ##STR1## wherein R represents an alkyl group; and (c) a compound serving as a reaction medium capable of reversibly causing electron-donating/accepting reaction attributable to the components (a) and (b). This composition has a reversible metachromatic function that it presents a color-developed state when heated in a color-extinguished state and presents the color-extinguished state when temperature-dropped or cooled in the color-developed state, or that it begins to develop a color in the course of temperature drop after heating, having been triggered by its temperature rise when heated in a color-extinguished state, and returns to the color-extinguished state after it has presented a color-developed state in a maximum developed-color density.

Abstract: A microcapsulated pigment contains, as reaction media one or more specific aliphatic acid alcohol esters obtained from monohydric aliphatic alcohols having odd numbers of carbon atoms and aliphatic carboxylic acids, these reaction media in a homogeneous compatible state with chromatic components are occluded in microcapsules to obtain characteristics of thermochromism with a hysteresis range (segment HG) from 8.degree. C. to 30.degree. C.

Abstract: A composition of matter suitable for use in a reversible thermometer is disclosed which comprises a thermally responsive material capable of being supercooled at least for several minutes, and subject to a change in state from a solid to a liquid substantially at a predetermined temperature; means for visually observing the change in state; and a matrix forming material comprising an amorphous organic compound, the matrix forming material being insoluble in the thermally responsive material; whereby the thermally responsive material is dispersed within the matrix forming material, the composition of matter being reversibly responsive to changes in temperature, and remaining in the liquid state for a time sufficient to permit a user of the composition to observe the change in state. The preferred matrix forming material is polyisobutylene, and the preferred thermally responsive material is a solid solution of ortho-chloronitrobenzene and ortho-bromonitrobenzene.

Abstract: A clinical thermometer registers the maximum temperature reached and uses as the thermometric fluid a non-toxic gallium/indium alloy which adheres to the walls of the thermometer measuring tube, the adhesive force being greater than the internal cohesive force of the thermometric liquid. A Gallium/indium/tin eutectic alloy is particularly useful in such applications and others.

Abstract: A small sized temperature sensor for measuring temperatures in the body and for measuring temperatures in an extracorporeal blood circulation circuit, wherein the possibility of electrical shock and the cost are reduced, while resolution and reliability are increased. The temperature sensor comprises a source of light, an optical fiber to receive light from the light source at one end of the optical fiber, a transducer positioned near the other end of the optical fiber, a reflection means for reflecting the irradiated light, and an arithmetic processing unit which calculates temperature based upon the reflected light measured. The transducer is made up of at least two polymers that have different temperature dependencies of refractive index and form a microphase separation structure, wherein the polymers are cured products made from a cationically polymerizable compound having epoxy groups and a radically polymerizable compound having radically unsaturated groups.

Abstract: A ferrite device for sensing temperature is disclosed, which is useful for apparatuses such as hot water vessels, fire alarms, and general electronic apparatuses. More specifically, the ferrite device for sensing temperature is manufactured by stack-printing two or more ferrite layers having different Curie temperatures (Tc). Therefore, a mass production is possible with a low manufacturing cost, and control of the process conditions is easy. The temperature sensing ferrite device includes: upper and lower layers composed of a single ferrite material; a plurality of stacked layers stacked between the upper and lower layers and consisting of two or more ferrite subregions; each of the ferrite subregions of one of the plurality of stacked layers has a composition and a shape that are the same as a ferrite subregion in another of the plurality of stacked layers screw type electrodes provided on the respective ferrite subregions.

Abstract: An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually using a sensor chip and an accompanying color card.

Abstract: A method and apparatus for measuring the temperature profile of a surface exhibiting spatial and/or temporal variations in temperature, e.g., the surface of a machine or a biological system, is disclosed. The inventive method involves forming a layer of chemiluminescent material in thermal contact with the surface. The chemiluminescent activity is selected to be a function of temperature by suitable dye choices. The resulting luminescence is detected.

Abstract: A reversible thermochromic composition develops fluorescent color of yellow, yellowish orange, orange, reddish orange, or red with a high color density and high color brightness, yet gives no residual color under non-color-developing conditions, and has remarkably improved light resistance. The reversible thermochromic composition, comprising a solubilized mixture of three components of (a) an electron-donating color-developing organic compound selected from pyridine types, quinazoline types, and bisquinazoline types of compound, (b) an electron-accepting compound for the electron-donating color-developing organic compound, and (c) a compound serving as a reaction medium for causing reversibly an electron exchange reaction between the components (a) and (b) within a specified temperature range.

Abstract: An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually or by utilizing an optical fiber and an electrical sensing circuit.

Abstract: A reversible optical temperature indicator utilizes thermochromic semiconductors which vary in color in response to various temperature levels. The thermochromic material is enclosed in an enamel which provides protection and prevents breakdown at higher temperatures. Cadmium sulfide is the preferred semiconductor material. The indicator may be utilized as a sign or in a striped arrangement to clearly provide a warning to a user. The various color responses provide multiple levels of alarm.

Abstract: A maximum temperature indicator comprises a body of inexpensive and highly durable polymeric material adapted to be affixed to a support, such as within a mechanical device. The polymeric material undergoes a detectable physical change unique to a maximum temperature to which the polymeric material was exposed. After exposure, the polymeric material is easily tested to accurately determine the maximum temperature that the sample was exposed to.

Abstract: There are provided a thermochromic opaque composition capable of exhibiting change in transparency together with change in color in response to temperature variation, a laminate member employing the same, and a three-dimensional article capable of concealing and revealing the interior, utilizing the laminate member. The thermochromic oaque composition is formed by dispersing a thermochromic material, capable of developing and erasing color by an electron donating-accepting reaction, in small particles in vinyl chloride-vinyl acetate matrix resin. The above-mentioned structure realizes reversible change in transparency, together with change in color, in response to temperature variation, with hysteresis with a temperature difference of 10.degree. C. at minimum to 50.degree. C. between the high and low trigger temperatures.

Abstract: A color changing pigment composition which changes color reversibly when ted comprising (a) a cyclic aryl lactone dye, (b) a diaminoalkane activator and (c)an ester. The pigment composition can also include a white pigment such as titanium dioxide as an opacifier or a yellow dye such Hansa yellow G. The pigment composition changes from a dark color, e.g. blue, to white when the composition is heated to a specified temperature, e.g. to a temperature of 52.degree. C., and reversibly changes from white back to the blue color when the pigment composition is cooled, e.g. to a temperature below about 25.degree. C.

Abstract: The present invention relates to the effective leak detection of refrigerants by the addition of dyes from the general chemical class of naphthalimide fluorescent dyes in a refrigeration system where said refrigeration system employs alone, or in combination, a refrigerant in a hermetic system such as, but not limited to, chlorofluorocarbons (CFC), hydrochlorofluorocarbons (HCFC), hydrofluorocarbons (HFC) and any hydrogen, halogenated or ether derivatives of the methane, hydrogen, halogenated, ether or cyclic derivatives of either ethane, propane, butane, pentane, mixtures of HCFC, HFC, hydrocarbons, carbon dioxide and ammonia.Leakage is determined by inspection of the sealed system using a lamp having an emission wavelength from 300 to 480 nanometers providing an indication of any system leakage.

Abstract: Refrigerant leakage in heating, ventilating and air conditioning systems employing hydrofluorocarbon refrigerants is determined by adding a mixture of predetermined amounts of a naphthalamide optical brightener with an appropriate lubricant to the system. Inspection of the system under ultraviolet light provides an indication of any leakage occurring in the system of liquid and/or gas.

Abstract: Laser-writable, black-colored blends of carbonate and polyester resins are provided by the incorporation of a black colorant formulation comprising carbon black and a fatty acid metal salt. Zinc stearate is a preferred fatty acid metal salt. The black-colored resin blends can be inscribed using standard YAG lasers and maintain an excellent balance of other properties including surface aesthetics, physical properties, heat resistance, chemical resistance and processability.

Abstract: A temperature sensor has a body whose thermal expansion is evaluated in the event of a change in temperature, there being deposited on the body a layer which has a layer structure containing less than 8% by weight of phosphorus, preferably containing up to 3% by weight of phosphorus, up to 2% by weight of an element of main group IV or main group V, in particular antimony, and up to 5% by weight of a transition metal element, in particular cobalt. The percentages by weight resulting from the sum being increased up to 100% with nickel. The layer modifies the magnetic flux in a coil arrangement comprising at least one coil. This change in the magnetic flux in the coil arrangement is evaluated and the change in the magnetic flux being detected as a change in the inductance. The change in length of the body and the change in temperature are deduced therefrom.

Abstract: A heat-sensitive recording composition comprising agglomerates which comprise an aromatic isocyanate compound, an imino compound and a sensitizer and have an average diameter of 2-30 .mu.m; and a process for producing the composition are disclosed. This heat-sensitive recording composition is excellent in heat response and high in sensitivity. From the point of image stability, the agglomerates are preferably contained in microcapsules together with a polymer.

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: An inorganic thermochromic substance is proposed which is a composite oxide of strontium and manganese in a specified molar ratio as prepared by the calcination of a powder blend of strontium carbonate and manganese dioxide, instead of conventional manganese carbonate, at a specified temperature for a specified length of time. The temperature of the thermochromic color change is about -130.degree. C., much lower than the color-change point of most of conventional thermochromic substances. The color of the composite oxide is grey or pale green at room temperature but reversibly changes to pale red when it is chilled to -130.degree. C. or lower.

Abstract: The invention relates to a heat-shrinkable article that is at least partially coated with a temperature indicator. This temperature indicator is composed of an organic polymer having a suitable bonding agent, whereby the organic polymer is contained therein in a finely ground condition. As a result of this condition, the appearance of the agent is opaque and has a color corresponding to the degree of granulation and material constituent. When the melting point of the composition is reached, the material melts and becomes transparent or at least translucent. The color of the article shows through, so that this color change can be interpreted as a temperature indication.

Abstract: A temperature sensing system has a signal means which provides a signal representative of a temperature responsive luminescence, where the luminescence has a characteristic time-rate-of-decay. A means for comparison is connected to the signal means and samples the signal during two time intervals, the first interval overlapping the second. The averages of the samples are compared to provide a difference signal representative of the difference between the two measured averages. Control means coupled to the comparison means provide an output representing the temperature as a function of the time-rate-of-decay, by adjusting the overlapping intervals so that the difference signal converges to a preselected limit.

Abstract: A container for a liquid crystal cumulative dosimeter 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 second constituent. The barrier is formed either by encapsulating one or both of the constituents or by using air bubbles. Methods of manufacturing the various containers shown and processes of using those containers are also disclosed.

Abstract: A temperature measuring device useful for measuring the temperature of urine samples is disclosed comprising a solid solution having incorporated therein a nucleating agent and an indicating dye system. The preferred solid solution is a mixture of ortho-chloronitrobenzene and ortho-bromonitrobenzene. The preferred dye systems are pinacyanol iodide and a mixture of bromcresol purple and ethyl red. A novel aspect of the thermometer is that it is adapted to indicate a predetermined temperature at an observable initiation of melt temperature which is about 0.3.degree. to about 1.9.degree. F. below the completion of melt temperature of the composition. The thermometer is a real time device.

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: The present invention rleates to the effective leak detection of refrigerants by the addition of dyes from the general chemical class of naphthalimide fluorescent dyes in a refrigeration system where said refrigeration system employs alone, or in combination, a refrigerant in a hermetic system such as, but not limited to, chlorofluorocarbons (CFC), hydrochlorofluorocarbons (HCFC), hydrofluorocarbons (HFC) and any hydrogen, halogenated or ether derivatives of the methane, hydrogen, halogenated, ether or cyclic derivatives of either ethane, propane, butane, pentane, mixtures of HCFC, HFC, hydrocarbons, carbon dioxide and ammonia.Leakage is determined by inspection of the sealed system using a lamp having an emission wavelength from 300 to 480 nanometers providing an indication of any system leakage.

Abstract: Refrigerant leakage in heating, ventilating and air conditioning systems employing hydrofluorocarbon refrigerants is determined by adding a mixture .[.of.]. .Iadd.including .Iaddend.predetermined amounts of a napthalamide optical brightner .[.with an appropriate lubricant.]. to the system. Inspection of the system under ultraviolet light provides an indication of any leakage occuring in the system of liquid and/or gas.