Chemically Activated Type Patents (Class 116/206)
  • Patent number: 5727498
    Abstract: A retractable indicator assembly 10 may be mounted on a container C which transmits air through the container and removes deleterious gases with an activated charcoal medium M in the container. An elongate indicator housing 12 has a chamber 20 therein. A male adaptor 14 has external threads 16 for sealing engagement with the container. A plug 40 is provided at the upper end of the housing 12. Housing 12 includes a transparent wall portion 28 for viewing at least a portion of the chamber 20. A litmus indicator 42 is moveable by a retractable rod 54 from a retracted position within the container to an extended position within the chamber 20 of the housing 12. An outer housing 64 is secured to the upper end of the rod 54, and protects the indicator housing 12 while the litmus indicator 42 is in its normally retracted position.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: March 17, 1998
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: George R. Hackler, Ronald J. Gamboa, Victor Dominquez
  • Patent number: 5717972
    Abstract: A cartridge (10) of photographic medium includes a housing (14-24) having an interior volume (15); an exit slit (26) from the interior volume to an exterior of the housing; a photographic medium element (12) enclosed within the interior volume; an indicator (36-44) supported by one of the housing and the medium element, the indicator being responsive to a liquid reagent to change color and provide a visible indication of a status of the medium element; a source (46-52; 72-76; 90; 112) of the liquid reagent supported by the one of the housing and the medium element; and means (32, 34, 54-62; 778-86; 94-100; 22, 26, 28, 110) for causing flow of the reagent to the indicator upon movement of the medium element through the exit slit, whereby the indicator will change color and indicate the status. An indicator apparatus for mounting on a cartridge and a photographic medium supporting an indicator and source of reagent also are disclosed.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: February 10, 1998
    Assignee: Eastman Kodak Company
    Inventors: David L. Patton, Virginia M. Moszkowicz, William G. Hoyt, Edgar G. Earnhart
  • Patent number: 5707680
    Abstract: There is disclosed a method for the time-delayed defacement of all or part of a printed work, such as a time-dependent coupon. Such method comprises applying opaque print onto a substrate and applying an opacity-labile composition of lesser nascent opacity than the visible print onto the substrate in such a manner that a change in the opacity of the opacity-labile composition causes a time-delayed defacement of the printed substrate.
    Type: Grant
    Filed: January 2, 1996
    Date of Patent: January 13, 1998
    Inventor: Steven Jerome Moore
  • Patent number: 5666949
    Abstract: An exposure indicating apparatus and indicating method includes a sensor having a property responsive to a concentration of a target species. A processing device generates a concentration signal as a function of the property and an indicator is activated as a function of the concentration signal. The indicator is activated at a signaling rate indicative of an exposure indicating apparatus operating within predefined design parameters and at an exposure signaling rate indicative of the concentration attaining a predetermined threshold concentration. The indicator may also be activated at a signaling rate indicative of an exposure indicating apparatus operating outside of the predefined design parameters, and after the predetermined threshold concentration is attained, the indicator may be activated at an exposure signaling rate which varies as a function of the concentration signal.
    Type: Grant
    Filed: October 24, 1994
    Date of Patent: September 16, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Mark K. Debe, Lowell R. Miller, Edward E. Parsonage, Richard J. Poirier, Gregory Yuschak
  • Patent number: 5630372
    Abstract: An improved on demand useful life indicator that may be attached to or placed in manufactured goods at a selected time. This indicator includes a base member; an indicating material layer, an adhesive layer, and a co-layered covering material. The indicating material layer is formulated to provide a visual indication when exposed to a selected component of an ambient fluid. The indicating material is applied to one side of the impermeable base member in a selected pattern. The adhesive layer is made of an impermeable material and applied in a selected pattern over the indicating material layer so that at least one selected portion of the indicating material is exposed to the ambient fluid. An inner layer of the co-layered cover member has a greater adhesion to the adhesive layer when an impermeable outer layer is removed. The inner layer is permeable to the ambient fluid. The useful life indicator remains in a selected state of dormancy until the outer layer of the co-layered cover member is removed.
    Type: Grant
    Filed: July 25, 1995
    Date of Patent: May 20, 1997
    Inventors: Joseph W. Ramsey, Peter L. Gill
  • Patent number: 5620656
    Abstract: Devices useful to monitor whether or not an article has been exposed to sterilizing conditions are provided and comprise a package and an indicator associated with the package. The package is sufficiently permeable to admit sterilizing gas or vapor into the package. The indicator associated with the package changes color from a first color (indicating ambient conditions) to a second color (indicating exposure to acidic gas or vapor). Both the first and second colors of the indicator are stable and preferably substantially maintain their colors under ambient conditions. Particularly, preferred embodiments are adapted for use with peracetic acid sterilization processes.
    Type: Grant
    Filed: December 4, 1995
    Date of Patent: April 15, 1997
    Assignee: Abtox, Inc.
    Inventors: Afaf Wensky, Phillip A. Martens, Ross A. Caputo
  • Patent number: 5617812
    Abstract: A tamper evident system for indicating when a closed enclosure (24) has been opened comprises a window (21) and a sensor (22) colour sensitive to presence of a gas. The sensor (22) is located in the enclosure (24) so as to be visible through the window (21). Any compositional change of gas in the enclosure (24) is signalled by a change of colour of the sensor (22).
    Type: Grant
    Filed: July 16, 1996
    Date of Patent: April 8, 1997
    Assignee: Sealed Air (NZ) Limited
    Inventors: Simon N. Balderson, Robert J. Whitwood
  • Patent number: 5602804
    Abstract: The time indicator device of this invention is provided with a display layer with at least one defined display region therein. A migration layer is provided which overlies and is attached to the display layer. The migration layer has at least one migration region therein and in use each migration region is in contact with at least one display region. An activation layer is provided which has at least one defined activation region therein. The activation region includes a migrating agent capable of migrating laterally through the migration region. When the activation layer overlies the migration layer, each activation region overlies at least one migration region. The migration region connects each activation region with at least one display region which is laterally distal from the activation region. In use and in order to activate the device the activation layer and migration layer are adhesively attached to each other.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: February 11, 1997
    Assignee: Temtec Inc
    Inventor: David J. Haas
  • Patent number: 5555223
    Abstract: A process for producing or packing an item with a limited period of use or interest, e.g. a regularly issued periodical or foodstuffs to be consumed within a limited time, in which the consumer item or its packaging is fitted by adhesive means or other means of attachment with a timer having an indication which, close to the time of the production of the consumer item (2), especially at the time of securing to the consumer item or its packing, is set and/or otherwise configured to synchronize its indicator with the actual time, and consumer items produced by the process.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: September 10, 1996
    Inventor: Markus Barainsky
  • Patent number: 5529841
    Abstract: A field test kit for determining quantity of hydrogen sulfide in a liquid st sample. The test kit includes a test container with an opening for a liquid test sample containing hydrogen sulfide gas and a cap provided over the opening. The cap has colorimetric particulate indicator on its top inside surface. A silicone barrier disposed over the indicator protects the indicator from contact with the test sample.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: June 25, 1996
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Rex A. Neihof
  • Patent number: 5517985
    Abstract: An apparatus (14) for detecting carbon dioxide in exhaled gas is disclosed. The apparatus comprises an indicating element (10) for changing color when exposed to carbon dioxide and a carbon dioxide shield (12) for absorbing a predetermined level of carbon dioxide from the exhaled gas before exposing the indicating element (10) to the exhaled gas.
    Type: Grant
    Filed: November 2, 1994
    Date of Patent: May 21, 1996
    Inventors: Gilbert M. Kirk, James D. Bickley
  • Patent number: 5435010
    Abstract: An article of clothing that changes color when exposed to varying moisture levels within the article. The article has a body with an outer surface, and a moisture sensitive coating disposed upon the outer surface of the body that changes color when in contact with varying moisture levels in the body.
    Type: Grant
    Filed: October 18, 1993
    Date of Patent: July 25, 1995
    Inventor: Robert E. May
  • Patent number: 5415809
    Abstract: A method for determining the concentration of dissolved oxygen in a water sample comprising the steps:(a) providing a water sample of predetermined volume, the oxygen content of which is to be determined;(b) mixing additives with the water sample to form a mixture, the additives comprising an oxidizable metal salt comprising a transition metal cation selected from the group consisting of scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel and copper, and an anion selected from the group consisting of an inorganic anion and an organic anion which, with the cation, results in a water soluble oxidizable metal salt, at least one water soluble alkali metal compound selected from the group consisting of an alkali metal oxide and an alkali metal hydroxide and at least one oxidation-reduction indicator capable of a color change upon oxidation of the metal salt;(c) preventing any substantial contact of the mixture with atmospheric oxygen; and(d) comparing the color of the mixture to a predetermined
    Type: Grant
    Filed: July 15, 1992
    Date of Patent: May 16, 1995
    Assignee: Aquarium Pharmaceuticals, Inc.
    Inventors: Jesse Elson, Michael Yoshpa
  • Patent number: 5383338
    Abstract: An in-line sight indicator structure for a fluid system wherein a chamber defining flow-through sight housing includes a sight glass in one wall portion thereof and a support member extending from an opposite wall portion in spaced relation to the sight glass to support an indicator element mounted thereon within a fluid stream passed through the chamber, the housing being hermetically sealed from ambient.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: January 24, 1995
    Assignee: Emerson Electric Co.
    Inventors: Benjamin Bowsky, George J. Sciuto
  • Patent number: 5377496
    Abstract: An improved vapor compression refrigeration system that has an indicator for detecting the presence of acid contamination in the refrigerant contained in the system. The indicator is permanently or semipermanently installed so that continuous monitoring of the refrigerant for acid is possible. The indicator is located in a portion of the system where the refrigerant is always in a gaseous state. In a preferred embodiment, the indicator is located in a bypass line between the suction and the discharge of the system compressor. The indicator preferably shows the presence of acid by a color change, visible from a point external to the indicator, in an indicator bed in the indicator. The color change may be either permanent or the indicator bed may return to its original color when the acid contamination is no longer present in the refrigerant.
    Type: Grant
    Filed: October 5, 1993
    Date of Patent: January 3, 1995
    Assignee: Carrier Corporation
    Inventors: Nancy M. Otto, Warren R. Clough, Henry B. Balduzzi
  • Patent number: 5375592
    Abstract: An apparatus (14) for detecting carbon dioxide in exhaled gas is disclosed. The apparatus comprises an indicating element (10) for changing color when exposed to carbon dioxide and a carbon dioxide shield (12) for absorbing a predetermined level of carbon dioxide from the exhaled gas before exposing the indicating element (10) to the exhaled gas.
    Type: Grant
    Filed: April 8, 1993
    Date of Patent: December 27, 1994
    Inventors: Gilbert M. Kirk, James D. Bickley
  • Patent number: 5349718
    Abstract: An improved wiper blade of the type used on a vehicle windshield having an indicator means painted on the wiper blade which indicates that the wiper blade should be replaced. The exposure to UV light of the indicator painted on the wiper blade causes it to change in color and thus communicate to the user that it is time to change. The indicator paint is a silicone resin paint and would be applied to a wiper blade made of a resilient elastomeric material which is degraded with exposure to UV light in the atmosphere.
    Type: Grant
    Filed: August 9, 1991
    Date of Patent: September 27, 1994
    Assignee: JMK International, Inc.
    Inventor: Robert M. Gibbon
  • Patent number: 5323774
    Abstract: A breathing mask with a mask interior, through which the respiration air flows, and with a detection device with an indicator for indicating the presence of a toxic substance having penetrated into the breathing mask, is to be improved such that the indicator can be activated when the breathing mask has been put on. To accomplish this task, the detection device (1), which gas-tightly surrounds the indicator (6), has an operating means (5), which can be operated from the outside (21) of the mask, and with which the indicator (6) can be brought into contact with the respiration air in the mask interior (22) when the breathing mask has been put on.
    Type: Grant
    Filed: February 23, 1993
    Date of Patent: June 28, 1994
    Assignee: Dragerwerk AG
    Inventor: Kai-Uwe Fehlauer
  • Patent number: 5317987
    Abstract: An indicator for attachment to objects to display elapsed times and/or changes of state, in which a visible display is brought about by color change of the indicator upon reaction of chemical substances and with destruction of a barrier preliminarily separating the chemical substances. The barrier is a separating or covering layer that can be penetrated by selective pitting by a chemical substance preliminarily enclosed by the barrier. An embodiment of the invention includes selective pitting of the barrier member with a resulting visible change of the indicator. Another embodiment of the invention includes initial separation of two chemical substances that can react with one another with visible change, of which at least one reacts chemically with the barrier for the latter's penetration.
    Type: Grant
    Filed: May 4, 1992
    Date of Patent: June 7, 1994
    Assignee: Badische Tabakmanufaktur Roth-Handle GmbH
    Inventors: Hubert Muller, Bruno Langenfeld
  • Patent number: 5306466
    Abstract: A food contamination detector. The detector comprises a tray for holding a food product. A collector is placed in the tray for collecting liquids from the food. A bar code detector is located in the collector.
    Type: Grant
    Filed: May 19, 1993
    Date of Patent: April 26, 1994
    Assignee: California South Pacific Investors
    Inventor: Robert M. Goldsmith
  • Patent number: 5293648
    Abstract: An indicator tag is provided for visually indicating the remaining effectiveness of a protective chemical treatment agent on a textile article. The tag is made from a fabric dyed with at least one dye to impart to the piece of fabric a predetermined initial color which indicates that the chemical treatment agent on the textile article is effective. The dye has a chromophore which is susceptible to degradation by reagents which would destroy the effectiveness of the chemical treatment agent so that exposure of the indicator tag to such reagents causes the indicator tag to change from its predetermined initial color to another color, thereby indicating that the textile article with which the indicator tag is used has been exposed to reagents which may cause a loss in the effectiveness of the protective chemical treatment agent on the textile article.
    Type: Grant
    Filed: October 28, 1991
    Date of Patent: March 15, 1994
    Assignee: Galey & Lord, Incorporated
    Inventor: Randolph L. Finley
  • Patent number: 5265538
    Abstract: A warning detonator for use on railway tracks or the like is disclosed. The detonator comprises a tube or cylinder (18) having disposed therein at spaced apart locations a length of elastomer (20) and a first explosive component (24, 25). A second explosive component (21) is located therebetween. The second explosive component (21) is also disposed within a cartridge (19) inside the cylinder (18). In use the cylinder (18) is affixed along a length of railway track in a manner whereby the wheel of a passing train progressively compresses the elastomer from its outer end so as to burst an end face (23) of the cartridge (19) and drive the second explosive component (21) into contact with the first explosive component (24, 25) to cause detonation thereof.
    Type: Grant
    Filed: July 29, 1992
    Date of Patent: November 30, 1993
    Inventor: Ronald S. Sampson
  • Patent number: 5253674
    Abstract: A fluid sensor for heat exchanger system includes a supporting device such as a tubular hose fitting for mounting the sensor in the system so that heat exchanging fluid circulated in the system comes into contact with the sensor. A window or sight glass is mounted in the supporting device along with corrodible separating means interposed between the sight glass and the heat exchanging fluid. A visual indicator such as a movable flap or a colored ball can be viewed through the sight glass when the separating means is ruptured or broken by corrosion. The viewing of the indicator provides an indication that the heat exchanging fluid has reached a certain corrosive state and requires replacement or treatment. In a preferred embodiment, the separating means is a metal diaphragm spaced from the sight glass.
    Type: Grant
    Filed: November 4, 1992
    Date of Patent: October 19, 1993
    Assignee: Long Manufacturing Limited
    Inventors: Charles S. Argyle, Brian E. Cheadle, Steven L. M. Bokor
  • Patent number: 5242830
    Abstract: A process and device for revealing impact(s) received by a substrate make use of a film capable of being deposited onto said substrate and consisting of a matrix in which are embedded microcapsules intended to be broken during the impact and thus to release product(s) which they enclose and which is (are) endowed with different photoluminenscence properties according to whether it is (they are) encapsulated or released into the matrix.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: September 7, 1993
    Assignee: Hutchinson
    Inventors: Gilles Argy, Andre Cheymol, Hubert Hervet
  • Patent number: 5228573
    Abstract: A method of packaging, comprising the steps of disposing an article in a package and airtightly sealing an air sensitive reagent, which changes color upon contact with air, as at least part of the package for the article such that the seal must be broken to access the article and thereby cause the reagent to contact the air or another agent and change color. A semi-permeable membrane will allow the same reagent to function as a shelf-life indicator.
    Type: Grant
    Filed: April 23, 1991
    Date of Patent: July 20, 1993
    Inventors: Richard Pavelle, Paul Burstein, Ronald M. Latanision
  • Patent number: 5221186
    Abstract: A wind turbine is arranged to provide for a front torroidal plate mounted from and spaced relative to a rear solid plate coaxially securing a deflecting cone coextensively and coaxially between the front and rear plate, with a series of equally spaced arcuate impeller blades mounted adjacent a periphery of the front and rear plates exteriorly of the cone to direct air flow through the turbine plates from the cone structure. The impeller also has a fluidic rotation indicator. The indicator is a set of arcuate liquid chambers which contain two different fluids of different colors and specific gravities. When the impeller is stationary, the two different fluids separate, indicating two colors. However, when the impeller rotates, the two fluids mix and indicate a single third color.
    Type: Grant
    Filed: October 23, 1991
    Date of Patent: June 22, 1993
    Inventor: Thomas H. Machin
  • Patent number: 5181536
    Abstract: A fluid sensor for heat exchanger system includes a supporting device such as a tubular hose fitting for mounting the sensor in the system so that heat exchanging fluid circulated in the system comes into contact with the sensor. A window or sight glass is mounted in the supporting device along with corrodible separating means interposed between the sight glass and the heat exchanging fluid. A visual indicator such as a movable flap or a colored ball can be viewed through the sight glass when the separating means is ruptured or broken by corrosion. The viewing of the indicator provides an indication that the heat exchanging fluid has reached a certain corrosive state and requires replacement or treatment. In a preferred embodiment, the separating means is a metal diaphragm spaced from the sight glass.
    Type: Grant
    Filed: January 16, 1992
    Date of Patent: January 26, 1993
    Assignee: Long Manufacturing Limited
    Inventors: Charles S. Argyle, Brian E. Cheadle, Steven L. M. Bokor
  • Patent number: 5182212
    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.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: January 26, 1993
    Assignee: Oscar Mayer Foods Corporation
    Inventor: Thomas J. Jalinski
  • Patent number: 5158349
    Abstract: A method of fabricating chemical lighting devices, comprising coextensive inner and outer tubes, wherein the inner tube contains multiple, segregated oxalate components, is described. Upon activation the device generates a distinct multi-color array of light.
    Type: Grant
    Filed: July 3, 1991
    Date of Patent: October 27, 1992
    Assignees: Lexington & Associates, Inc., Liquid Labs, Inc.
    Inventors: Stanley Holland, Luc Noel, Jerome Renard
  • Patent number: 5127433
    Abstract: A fluid sensor for heat exchanger system includes a supporting device such as a tubular hose fitting for mounting the sensor in the system so that heat exchanging fluid circulated in the system comes into contact with the sensor. A window or sight glass is mounted in the supporting device along with corrodible separating means interposed between the sight glass and the heat exchanging fluid. A visual indicator such as a movable flap or a colored ball can be viewed through the sight glass when the separating means is ruptured or broken by corrosion. The viewing of the indicator provides an indication that the heat exchanging fluid has reached a certain corrosive state and requires replacement or treatment. In a preferred embodiment, the separating means is a metal diaphragm spaced from the sight glass.
    Type: Grant
    Filed: November 8, 1990
    Date of Patent: July 7, 1992
    Assignee: Long Manufacturing Ltd.
    Inventors: Charles S. Argyle, Brian E. Cheadle, Steven L. M. Bokor
  • Patent number: 5128106
    Abstract: An oxygen detector for use in a double envelope lamp is described. The detector may be formed by nitriding a metal surface to produce a metal piece with a first visual color or state. The surface thickness is sufficient to exclude oxygen during normal assemble, but thin enough to change colors during lamp operation if oxygen is present.
    Type: Grant
    Filed: July 12, 1990
    Date of Patent: July 7, 1992
    Assignee: GTE Products Corporation
    Inventors: Jeffrey P. Buschmann, Arnold E. Westlund, Jr.
  • Patent number: 5112768
    Abstract: A method and device involving use of the reaction product of an aldehyde acidified with sulfuric acid in acetone for sensing moisture. The reaction product is used as a coating for colorimetric detection of humidity, the color of the coating changing as a function of the humidity level. The coating is applied to a thin layer chromatography plate which is received in a badge housing to provide a real-time colorimetric dosimeter for monitoring humidity and indicating its presence.
    Type: Grant
    Filed: June 18, 1990
    Date of Patent: May 12, 1992
    Inventor: Patricia T. Carver
  • Patent number: 5095844
    Abstract: A water detection plug for use in a marine engine or the like having lubricants such as oil contained therein including an arrangement for indicating the presence of water in the lubricant when the water is in contact with the plug such that the indicator arrangement presents a first distinct visual appearance when not in contact with water and a second distinct visual appearance different from the first visual appearance when the plug is in contact with water, thereby generating a visual signal which is visible to an observer located outside the device when the lubricant in contact with the plug becomes mixed with water.
    Type: Grant
    Filed: February 14, 1991
    Date of Patent: March 17, 1992
    Inventor: Phillip L. Alexander
  • Patent number: 5053339
    Abstract: A color changing device for monitoring the time-temperature storage history, i.e. shelf life, of perishable products. The device is constructed of an activator tape, containing an activator composition matrix, an indicating tape, containing an indicating composition matrix and an optional barrier matrix between the activator tape and the indicating tape. At least one matrix is a pressure sensitive adhesive. The activating composition, e.g. an organic acid such as citric acid, diffuses through the barrier and/or indicating matrix to continuously contact the indicating composition, e.g. an acid-base dye indicator such as 2,2',4,4',4",-pentamethoxy triphenylmethanol, to produce a visually observable color change at the temperature being monitored. The color intensifies with time and temperature, as more activator composition diffuses into the indicating matrix.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: October 1, 1991
    Assignee: J P Labs Inc.
    Inventor: Gordhanbhai Patel
  • Patent number: 5048334
    Abstract: A method and an apparatus for determining the thickness of a layer of a first liquid above an interface formed by the first liquid and the second liquid underlying the first liquid in a subterranean formation. The apparatus includes an elongated metal rod having a sharpened distal end. An electrode is provided adjacent the sharpened distal end to indicate when the interface formed by the two liquids has been reached. A lengthwise running elongated slot is provided in the outer surface of the body of the metal rod and contains an indicator strip. The indicator strip is adapted to undergo a color change upon contact with the first liquid. By measuring the length of the indicator strip which has undergone a color change, the thickness of the layer of the first liquid can be determined.
    Type: Grant
    Filed: August 22, 1990
    Date of Patent: September 17, 1991
    Assignee: The Board of Trustees of Western Michigan University
    Inventors: Duane R. Hampton, Ross Wagner, James Howell
  • Patent number: 5047100
    Abstract: Curcumin is employed for the purpose of detecting and warning of the presence of cyanide in a food, drug, or other oral composition. The curcumin is incorporated into a food packaging material. In the presence of cyanide, the curcumin undergoes a color change causing at least a portion of the packaging material to manifest a color change. The color change is sufficient to be detected by an observer, thereby providing a warning of cyanide adulteration of the product.
    Type: Grant
    Filed: July 18, 1989
    Date of Patent: September 10, 1991
    Assignee: Northwestern Chemical Co.
    Inventors: Susan Raymond, Michael J. Greenberg, Firoz Rajani
  • Patent number: 5045283
    Abstract: A moving boundary device for monitoring the time-temperature storage history, i.e. shelf life, of perishable products. The device is constructed of an activator tape, containing an activator composition in an activator matrix, an indicating tape, containing an indicating composition in an indicator matrix in which the matrices are adhered together to form a wedge-shaped composite matrix, preferably by means of a pressure sensitive adhesive. The device operates by allowing the activating composiiton, e.g. an organic acid such as citric acid, to diffuse through the increasingly thicker composite matrix to continuously contact the indicating composition, e.g. an acid-base dye indicator such as 2,2',4,4',4",-pentamethoxy triphenylmethanol, to produce a visually observable color change at the temperature being monitored. The color change appears as a moving boundary at the color/non-color interface which moves transversely along the length of the device toward the thicker end of the composite matrix.
    Type: Grant
    Filed: August 2, 1988
    Date of Patent: September 3, 1991
    Assignee: JP Labs Inc.
    Inventor: Gordhanbhai N. Patel
  • Patent number: 4999035
    Abstract: A device for indicating humidity in a line. A T-fitting has a cross bar portion connected in series with the line. An upright portion of the T-fitting extends outwardly from the cross bar portion. A hollow indicator body is mounted on the upright portion with a bore in the upright portion in communication with the hollow interior of the body. An end portion of the hollow interior of the body is exposed behind a transparent plate. A chamber is formed in the hollow interior of the body, and a humidity sensitive pad in the chamber is visible through the transparent panel.
    Type: Grant
    Filed: January 13, 1989
    Date of Patent: March 12, 1991
    Assignee: American Dry Air Products Company, Inc.
    Inventor: Eugene R. Warndorf
  • Patent number: 4987849
    Abstract: A signal device consisting of first and second inks applied to a surface. The first ink is sensitive to either light or air. The second ink is stable in the presence of light and/or air. The surface having first and second areas, wherein the second ink is applied in work or character form to said first area to form a signal word. The first ink is applied to the second area and is of a color so as to cooperate with the second ink to camouflage the signal word. A protective shield blocks the sensitive ink from exposure to light and/or air, wherein after a metered period of time of exposure to light or air the sensitive ink fades such that the contrast in color between the faded sensitive ink and the stable ink reveals the signal word.
    Type: Grant
    Filed: September 22, 1989
    Date of Patent: January 29, 1991
    Inventor: Daniel A. Sherman
  • Patent number: 4932247
    Abstract: A warning device for detecting mineral oil impurities in the brake fluid of hydraulic vehicle brake systems is described. The warning device comprises a body which is arranged in the brake fluid and can swell as a result of mineral oil and the change of shape of which indicates the presence of mineral oil impurities. The indication is given particularly as a result of the fact that the change in shape brought about by the swelling causes the opening or closing of an electrical circuit and thereby actuates a visual or acoustic indicator in the dashboard of the vehicle.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: June 12, 1990
    Assignee: Daimler-Benz AG
    Inventor: Bruno Gorres
  • Patent number: 4924799
    Abstract: An indicator for detecting whether the indicator has been inverted or tilted beyond a critical angle. The indicator includes a pair of reactants contained within two discrete reservoirs which are separated by a fluid passageway. When the indicator is tilted beyond the critical angle the reactants are contacted producing a reaction product having a color change. The indicator also provides a splash protector to prevent false positive reactions when the unit is agitated but has not been tilted. A first reactant is contained within a frangible ampule that can be broken when the indicator is activated for use. The color change is visible from the outside of the container.
    Type: Grant
    Filed: September 26, 1988
    Date of Patent: May 15, 1990
    Assignee: Universal Protection Corp.
    Inventor: John F. Rilling
  • Patent number: 4917503
    Abstract: A photoactivated time-temperature indicator is based on a leuco base system. A thermally insensitive, white ("inactive") leuco base (or a mixture of such leuco bases) is mixed, preferably in a polymeric matrix, with a material that generates acid upon exposure to light. Photoexcitation, preferably by UV or near UV light, causes the formation of a thermally sensitive, color-forming ("active") product. Following this activation step, a progressive color development occurs at a rate that increases with temperature. The indicator is useful for monitoring the freshness of perishable products, particularly those stored at subambient temperature.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: April 17, 1990
    Assignee: LifeLines Technology, Inc.
    Inventor: Himangshu R. Bhattacharjee
  • Patent number: 4918003
    Abstract: A disposable package is adapted to simulate the steam permeability and other qualities of the linen pack previously used to test the functioning of a steam sterilizer using a biological test device. The biological test device comprises spores on an appropriate carrier, either in a self-contained biological device or as a spore strip. The biological test device is placed within applicant's specially constructed package and the package is placed within the sterilizer, which is then cycled through a conventional sterilization cycle. During the sterilization cycle, applicant's package simulates the standard sterilizer linen pack previously used for such tests. After the sterilization cycle, sterility of the spore preparation is evaluated by incubating the spores in a culture medium to determine whether the spore population has been adequately destroyed.
    Type: Grant
    Filed: September 29, 1988
    Date of Patent: April 17, 1990
    Assignee: Propper Manufacturing Company, Inc.
    Inventors: Louise Macaro, John Dyckman, Thomas A. Augurt, Andrew Zwarun
  • Patent number: 4909179
    Abstract: A porous web having a permanent humidity detecting sensor is disclosed in which a metal salt is permanently bonded in the porous web matrix. The metal salt undergoes a color change from its hydrated to its dehydrated state to detect a change in humidity of a surrounding environment. Nonwoven fibrous webs having a permanent humidity detecting sensor are especially adapted for containing materials such as fabric softeners that may be released upon the conditions of a conventional clothes dryer for treatment of the clothes and visual detection of the release of softener by color change of the humidity sensor.
    Type: Grant
    Filed: April 25, 1988
    Date of Patent: March 20, 1990
    Assignee: The Stearns Technical Textiles Company
    Inventor: James F. McBride
  • Patent number: 4848138
    Abstract: A gas monitor for detecting the presence of absence of a noble gas in the space between two window glazing panels. The monitor is preferably non-reactive with the noble gas, but reactive in a visible way with ambient air. When the noble gas leaks out of the space between the glazing panels and ambient air infiltrates, the monitor provides a visual indicator of the occurrence.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: July 18, 1989
    Inventor: John M. Marshall
  • Patent number: 4846095
    Abstract: Device for indicating a critical temperature, such as, for example, the freezing point of a liquid. The device comprises a sheet which is a layer having a multiplicity of micropores therein and a mixture comprising at least two liquids, said mixture incapable of wetting said sheet at a given temperature, but capable of wetting said sheet when the temperature of said mixture reaches a critical value, such as the freezing point of one of the liquids in the mixture. The micropores, or voids, in the microporous layer cause scattering of transmitted light, causing the microporous layer to appear opaque. When the voids are filled with a liquid having substantially the same index of refraction as the material of the microporous layer, the filled voids do not scatter transmitted light, thus rendering the microporous layer transmissive to visible light.
    Type: Grant
    Filed: October 2, 1987
    Date of Patent: July 11, 1989
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Jeffrey O. Emslander
  • Patent number: 4834017
    Abstract: A time-temperature integrator based on color changes produced by the chemical reaction between reducing sugars and amino groups (i.e. amino-acids, peptides, proteins) permits the verification of the thermal history during cooking at 85.degree.-100.degree. C. of a hermetically sealed package for inspection and which can not be removed or substituted without breaking the package.
    Type: Grant
    Filed: March 30, 1987
    Date of Patent: May 30, 1989
    Assignee: Frigorifico Rio Platense Saici Y F
    Inventors: Guillermo J. Favetto, Jorge Chiriffe, Osvaldo C. Scorza, Carlos A. Hermida
  • Patent number: 4822743
    Abstract: A reusable indicating material for detecting leaks in sealed structures and other closed bodies comprises a fabric saturated with an indicator solution containing an acid-base indicator, a surfactant, a buffering system and a humectant. The indicator solution remains reactive when the fabric is dry to the touch and will indicate the presence of leaks in the structure being tested by changing color when a reactive gas escapes from the structure being tested. Upon removal from the tested structure the indicator material reverts to its original color and is available for subsequent tests.
    Type: Grant
    Filed: December 13, 1984
    Date of Patent: April 18, 1989
    Assignee: Lockheed Corporation
    Inventor: Jeffrey G. Wegrzyn
  • Patent number: 4821671
    Abstract: A captive volume device containing a small amount of solid propellant and a safe life indicator such as a colorimeter material or a differential pressure sensor. As the propellant deteriorates, it expends a gas which changes the color of the colorimeter material or causes the differential pressure sensor to alter its position, indicating that the propellant material is useless.
    Type: Grant
    Filed: June 27, 1985
    Date of Patent: April 18, 1989
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Frank G. Borgardt
  • Patent number: 4812053
    Abstract: An activatable time-temperature indicator consists of an oxygen-sensitive reaction product of a triarylmethane dye and a decolorant that is coated on a substrate and covered by an oxygen barrier. Optinally, an oxygen-permeable layer is between the coating and the oxygen barrier. The indicator is activated by removing the oxygen barrier. Following this activation step, a progressive color development occurs at a rate that increases with temperature. The indicator is useful for monitoring the freshness of perishable products, particularly those stored at sub-ambient temperature.
    Type: Grant
    Filed: August 7, 1987
    Date of Patent: March 14, 1989
    Assignee: LifeLines Technology, Inc.
    Inventor: Himangshu R. Bhattacharjee