Minute Transparent Spheres Patents (Class 359/536)
  • Patent number: 6110558
    Abstract: An article of clothing 10 bearing a retroreflective applique 12 that has a binder layer 14 onto which a retroreflective layer 19 is disposed. The retroreflective layer 19 includes a layer of optical elements 16 and a metal reflective layer 18, and the binder layer 14 includes a thermoplastic copolymer that includes units which contain carboxyl groups. A retroreflective applique, which uses such a binder layer in conjunction with aluminum-coated or silver-coated optical elements, demonstrates very good home laundering durability.
    Type: Grant
    Filed: April 10, 1998
    Date of Patent: August 29, 2000
    Assignee: 3M Innovative Properties Company
    Inventors: Britton G. Billingsley, Vera L. Lightle
  • Patent number: 6100217
    Abstract: A retroreflective graphic article bearing a fluorescent legend comprising a retroreflective base sheet, an image layer containing one or more pigments and one or more fluorescent dyes and a dye-receiving layer containing fluorescent dye which migrated from the image layer. Also, a method for making such articles is provided.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: August 8, 2000
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Yoshiyuki Nagaoka
  • Patent number: 6074719
    Abstract: A multi-layer article comprises a fluoropolymer layer comprising interpolymerized units derived from vinylidene fluoride, and a melt-processable, substantially non-fluorinated polymer layer comprising a polyamide, polyimide, polyurethane, or a carboxyl, anhydride, or imide functionalized polyolefin. The non-fluorinated polymer layer further contains an aliphatic di-, or polyamine which provides increased adhesion between the fluoropolymer layer and the non-fluorinated polymer layer.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: June 13, 2000
    Assignee: 3M Innovative Properties Company
    Inventors: Tatsuo Fukushi, Paul J. Wang
  • Patent number: 6054208
    Abstract: Aliphatic polyurethane film forming mixtures, image bearing aliphatic polyurethane films, and image bearing retroreflective sheeting having such image bearing films are described. The image-bearing aliphatic polyurethane films of the invention comprise an aliphatic polyurethane film derived from a film-forming mixture comprising (A) an aliphatic polyurethane, and (B) at least one hydroxy-containing imidazoline surfactant represented by the formula ##STR1## wherein R is an aliphatic group containing from about 10 to about 22 carbon atoms and R.sup.
    Type: Grant
    Filed: January 16, 1998
    Date of Patent: April 25, 2000
    Assignee: Avery Dennison Corporation
    Inventors: Robert K. Rega, George H. Wise
  • Patent number: 6030687
    Abstract: A retroreflective vision control panel which includes an opaque sheet material coated with retroreflective light reflecting particles and a dark opaque color on the reverse side thereof, and an image formed over top the retroreflective particles using colored light permeable translucent inks or films to form an image thereon. The opaque sheet and image have a plurality of perforations spaced therethrough. Translucent light-permeable sheet material is provided on the back side of the panel and overlaid on one or the other side with translucent inks to form a second image. An observer on the front side of the panel will observe one or the other of the images, depending upon the relative intensity of the light incident on the front and back sides of the panel.
    Type: Grant
    Filed: March 3, 1999
    Date of Patent: February 29, 2000
    Inventor: Michael D. Andriash
  • Patent number: 6000804
    Abstract: To provide a retroreflective material which has high utilization efficiency of light and which can give a reflected light to various color tones: the retroreflective material in accordance with the present invention, which comprises synthesizing an incident light by giving a phase contrast to a part of the incident light, and emphasizing a light component of specific wavelength region by interference and returning a colored light that the color tone is different from the incident light to the incident direction of the light, and to provide a hologram reconstructor which reflect the light to the almost the same direction as the incident direction, when the linear light that has regular directionality is irradiated, and which comprises graphic design function, decorating function and high forgery prevention property by using said retroreflective material as the hologram reconstructor: the retroreflective reconstructor in accordance with the present invention laminates said retroreflective material and a hologra
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: December 14, 1999
    Assignee: Shiseido Co., Ltd.
    Inventor: Asa Kimura
  • Patent number: 5988822
    Abstract: Luminous retroreflective sheetings have a transparent cover layer, an optical layer disposed beneath the cover layer, and a reflective layer. The optical layer includes a first polymer layer and a monolayer of beads at least partially embedded therein. The reflective layer is disposed proximate a focal plane of the monolayer of beads. The monolayer of beads includes transparent beads that, in combination with the reflective layer, retroreflect incident light. The monolayer also includes light-emitting beads that emit light under the influence of an applied voltage or ultraviolet (UV) radiation. Processes for making such sheetings are also disclosed.
    Type: Grant
    Filed: November 19, 1998
    Date of Patent: November 23, 1999
    Assignee: 3M Innovative Properties Company
    Inventors: Hidetoshi Abe, Yoshinori Araki
  • Patent number: 5988821
    Abstract: This invention relates to lens type functional retroreflective sheeting having retroreflective regions and visual functionality presenting regions, the retroreflective sheeting comprising:a base sheet consisting of a support comprising a functional resin layer containing a functional pigment having light-storing or fluorescent properties, microspherical lens-embedding regions in which microspherical lenses are densely distributed on the surface of the functional resin layer of the support so as to form a mono-layer, and microspherical lens-free regions in which substantially no microspherical lens is embedded and the functional resin layer is exposed;a transparent protective film disposed above the microspherical lens-bearing surface of the base sheet; andbonds at which said base sheet and said transparent protective film are partly bonded together. This lens type functional retroreflective sheeting not only afford good visibility to viewers positioned in the direction of the light source (e.g.
    Type: Grant
    Filed: January 16, 1998
    Date of Patent: November 23, 1999
    Assignee: Nippon Carbide Kogyo Kabushiki Kaisha
    Inventors: Osamu Tanaka, Kiyohito Hiromitsu, Kunihiro Takao, Katsura Ochi
  • Patent number: 5984479
    Abstract: The present invention discloses lens-type retroreflective sheeting excellent in appearance and having constant thickness and desired retroreflective performance, wherein the transparent microspheres in the retroreflective layer are composed of transparent microspherical lenses (A) having a refractive index of 1.8 or more and transparent microspherical fillers (B) having a refractive index different by at least 5% from the refractive index of the lenses (A).
    Type: Grant
    Filed: August 25, 1997
    Date of Patent: November 16, 1999
    Assignee: Nippon Carbide Kogyo Kabushiki Kaisha
    Inventors: Katsura Ochi, Osamu Tanaka, Makoto Takeda
  • Patent number: 5975706
    Abstract: A reflective plate (10) is disclosed, comprising a substrate (1), a retroreflective sheet (2) adhered to the surface of said substrate and having substantially flat base portions (3) covered with said retroreflective sheet (2), the retroreflective sheeting having retroreflective elements and a light transmissive cover layer; and a plurality of projections (4) covered with said retroreflective sheet and present on the corners of regular polygons that are arranged to form a regularly repeated pattern, wherein the arrangement of the projections (4) satisfies the relationship 0.05<h/P<0.60.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: November 2, 1999
    Assignee: 3M Innovative Properties Company
    Inventor: Naoki Nakayama
  • Patent number: 5959775
    Abstract: A retroreflective article utilizing a solventless bead bond composition wherein the bead bond composition includes a urethane/acrylate interpenetrating polymer network in which the urethane polymer is a thermoplastic and the acrylate component is a thermoset. The solventless bead bond is applied as a mixture of diisocyanates, diols, multifunctional acrylates and additives and thermally cured to a rubbery, thermoplastic solid. At this point the bead bond can be softened or molded with the application of heat or stored for a period of time without loss of thermoplasticity. Final retroreflective sheeting constructions which possess superior adhesion to acrylics, toughness and high retroreflectance are achieved by curing the multifunctional acrylates with radiation.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: September 28, 1999
    Assignee: 3M Innovative Properties Company
    Inventors: William D. Joseph, Lee A. Pavelka
  • Patent number: 5939168
    Abstract: A retroreflective vision control panel which includes an opaque sheet material coated with retroreflective light reflecting particles and a dark opaque color on the reverse side thereof, and an image formed over top the retroreflective particles using colored light permeable translucent inks or films to form an image thereon. The opaque sheet and image have a plurality of perforations spaced therethrough. Translucent light-permeable sheet material is provided on the back side of the panel and overlaid on one or the other side with translucent inks to form a second image. An observer on the front side of the panel will observe one or the other of the images, depending upon the relative intensity of the light incident on the front and back sides of the panel.
    Type: Grant
    Filed: October 20, 1997
    Date of Patent: August 17, 1999
    Inventor: Michael D. Andriash
  • Patent number: 5917652
    Abstract: All-ceramic retroreflective elements which may be used in pavement markings comprising an opacified ceramic core and ceramic optical elements partially embedded into the core.
    Type: Grant
    Filed: March 2, 1998
    Date of Patent: June 29, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: James P. Mathers, Kathleen M. Humpal, Roger W. Lange
  • Patent number: 5910858
    Abstract: The present invention provides a retroreflective sheeting having a front surface and a back surface, the retroreflective sheeting retroreflecting light entering through the front surface, wherein the retroreflective sheeting comprises encapsulated-lens retroreflectors. The retroreflective sheeting includes a plurality of indentations in the back surface of the retroreflective sheeting and seal coat at least partially filling the indentations.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: June 8, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Cheryl M. Frey, Bruce B. Wilson
  • Patent number: 5900978
    Abstract: A material such as fabric, plastic, leather or paper incorporates retroreflective properties which result from the application of metal coated microbeads. Methods for the application of microbeads to various surfaces as well as the formulation of printing inks containing microheads are disclosed.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: May 4, 1999
    Assignee: Reflective Technology Industries Limited
    Inventors: Brian Sagar, Robert Moule
  • Patent number: 5896227
    Abstract: A method for forming retroreflective sheeting comprising a binder layer having a first surface with protrusions thereon and a plurality of retroreflective elements partially embedded in the surface, wherein the method comprises forming the binder layer in a first profile, embedding the retroreflective elements therein, and then activating that binder layer such that it is restored to the first profile via shape memory.
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: April 20, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Naoyuki Toriumi, Michiru Hata
  • Patent number: 5889615
    Abstract: Dual axis retroreflective articles and methods of using them are disclosed. The retroreflective articles may combine dual axis retroreflection with three axis retroreflection to provide a steady glow due to the three axis retroreflective portions of the article and also provide intermittent or flashing retroreflection as the plane of retroreflection from the dual axis retroreflector passes through or near the light source. The retroreflective articles may also include dual axis retroreflective structures in combination with sparkling reflective structures, as well as dual axis retroreflective structures in combination with both three axis retroreflective structures and sparkling reflective structures. Methods of use include moving the dual axis retroreflective structures to obtain intermittent or flashing retroreflection.
    Type: Grant
    Filed: June 27, 1997
    Date of Patent: March 30, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: John F. Dreyer, Kenneth M. White, Vera L. Lightle
  • Patent number: 5882771
    Abstract: The present invention provides a retroreflective sheeting including: optical elements arranged in substantially a monolayer; a spacing layer in which the optical elements are at least partially embedded; a specularly reflecting layer underlying the spacing layer; and a bead bond layer in which the optical elements are at least partially embedded. The bead bond layer includes an aminoplast-crosslinked polymer comprising urethane groups, wherein prior to crosslinking the polymer has a glass transition temperature (Tg) of less than about 0.degree. C.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: March 16, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Deana A. Klein, Carol-Lynn Spawn
  • Patent number: 5880885
    Abstract: Retroreflective article that provides effective retroreflective brightness at very high entrance angles as well as low entrance angles.
    Type: Grant
    Filed: June 27, 1996
    Date of Patent: March 9, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Terry R. Bailey, Louis C. Belisle, deceased, Larry K. Stump, Gregory F. Jacobs, David G. Schueler, Dale H. Haunschild
  • Patent number: 5835271
    Abstract: A retroreflective element that exhibits exceptional wet retroreflectivity, and a method of manufacturing the same. The retroreflective element includes an assembly having a multi-sided retroreflector and a clear thermoplastic. In one embodiment, the clear thermoplastic is at least partially thermally deformed to create a convex retroreflective dome for capturing high incident angle light rays. The retroreflective elements may be used in a pavement marking system, such as attached to pavement marking tape or deposited in pavement marking paint.
    Type: Grant
    Filed: June 29, 1995
    Date of Patent: November 10, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Larry K. Stump, Thomas V. Kusilek, David C. May, Terry R. Bailey, Louis C. Belisle
  • Patent number: 5824390
    Abstract: The present invention provides a method for producing retroreflective sheeting useful for marking or the like of signs such as road signs and construction signs; number plates of vehicles such as motorcars and motorcycles; materials for safety such as clothes and life jackets; signboards, etc.
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: October 20, 1998
    Assignee: Nippon Carbide Kogyo Kabushiki Kaisha
    Inventors: Katsura Ochi, Osamu Tanaka, Masaki Yoshizawa
  • Patent number: 5820988
    Abstract: A retroreflective sheeting have a multitude of retroreflective elements that include a layer of optical elements and a reflective element(s) that is positioned functionally behind the optical elements. The retroreflective elements are supported by a polymeric layer, and an adhesive layer positioned below the support layer. The adhesive layer contains a polyurethane crosslinked by at least an isocyanate compound. The polyurethane is polymerized from a component containing a polyol having at least one alkyl side chain in a molecule, and the adhesive has (i) a storage modulus of about 2.times.10.sup.7 to 8.times.10.sup.7 dyne per square centimeter when measured in a tensile mode at a frequency of 35 Hz and 25.degree. C., and (ii) a softening point of about 80.degree. C. to less than 200.degree. C.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: October 13, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Yoshiyuki Nagaoka
  • Patent number: 5822120
    Abstract: A retroreflective element which may be used in pavement markings comprising a core having (a) a central layer having first and second major surfaces and at least one vertical surface, (b) a barrier layer applied to the first major surface, and (c) a barrier layer applied to the second major surface; and a plurality of optical elements embedded in the vertical surface(s) of the central layer.
    Type: Grant
    Filed: February 5, 1996
    Date of Patent: October 13, 1998
    Inventors: Michael C. Palazzotto, Wayne S. Mahoney
  • Patent number: 5812317
    Abstract: An exposed lens retroreflective article 10 has in sequence a layer of microspheres 12, a polymeric intermediate layer 18, a metal reflective layer 16, and a polymeric binder layer 14. Microspheres 12 are partially embedded in the binder layer 14, and the intermediate layer 18 and the metal reflective layer 16 are disposed between the microspheres 12 and the binder layer 14 such that the intermediate layer 18 is in contact with microspheres 12. Retroreflective articles of this construction provide improved laundering durability.
    Type: Grant
    Filed: October 26, 1995
    Date of Patent: September 22, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Britton G. Billingsley, Robert J. Fleming
  • Patent number: 5784198
    Abstract: An encapsulated lens retroreflective sheeting that has a bonding layer that consists essentially of a thermoplastic polyurethane resin that has a softening point of 70.degree. C. to 200.degree. C. The bonding layer is sealed to a light transmissible surface protective layer by a multitude of bonds that form spaces between the protective layer and the bonding layer. Retroreflective elements are partially embedded in the bonding layer and interface with air in the spaces. An encapsulated lens retroreflective sheeting of this construction can be adhered to a highly plasticized plastic surface and maintain high adhesion force for an extended duration while at the same time maintaining good retroreflective performance.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: July 21, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Yoshiyuki Nagaoka
  • Patent number: 5777790
    Abstract: A retroreflective article comprising a monolayer of microspheres partially embedded in and protruding from a binder layer and specular reflector underlying the microspheres, wherein the monolayer of microspheres comprises a mixture of a first class of microspheres having a first refractive index and a second class of microspheres having a second refractive index wherein the second refractive index is higher than the first refractive index. As a result, the sheeting exhibits superior observation angle angularity.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: July 7, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Toshitaka Nakajima
  • Patent number: 5777791
    Abstract: Retroreflective articles, for example in the form of pavement markers or retroreflective elements, exhibit both wet and dry retroreflectivity by using a plurality of Type A microspheres and a plurality of Type B microspheres partially embedded in a binder layer containing specular pigments. The Type A and Type B microspheres have different average indices of refraction.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: July 7, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Thomas P. Hedblom
  • Patent number: 5759671
    Abstract: Ultraviolet luminescent retroreflective sheeting includes a retroreflective portion containing retroreflective elements and an ultraviolet luminescent portion to facilitate nighttime viewing by persons not located at or near a source of light being retroreflected by the retroreflective portion. At least part of the ultraviolet luminescent portion is provided as the bonding lines for bonding the transparent cover sheet to the support sheet to form a series of sealed cells in which the retroreflective elements, which may be of the encapsulated lens-type or the encapsulated cube-corner-type, are disposed. The ultraviolet luminescenct portion includes fluorescent agent which emits light when irradiation by ultraviolet irradiation.
    Type: Grant
    Filed: August 15, 1996
    Date of Patent: June 2, 1998
    Assignee: Nippon Carbide Kogyo Kabushiki Kaisha
    Inventors: Osamu Tanaka, Kiyohito Hiromitsu, Hidenori Fushimi
  • Patent number: 5738746
    Abstract: An article of clothing 10 bearing a retroreflective applique 12 that has a binder layer 14 onto which a retroreflective layer 19 is disposed. The retroreflective layer 19 includes a layer of optical elements 16 and a metal reflective layer 18, and the binder layer 14 includes a thermoplastic copolymer that includes units which contain carboxyl groups. A retroreflective applique, which uses such a binder layer in conjunction with aluminum-coated or silver-coated optical elements, demonstrates very good home laundering durability.
    Type: Grant
    Filed: December 18, 1995
    Date of Patent: April 14, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Britton G. Billingsley, Vera L. Lightle
  • Patent number: 5726803
    Abstract: The present invention comprises lens-type retroreflective sheeting which is excellent in appearance and having constant thickness and desired retroreflective performance, wherein the transparent microspheres in the retroreflective layer are composed of transparent microspherical lenses (A) having a refractive index of 1.8 or more and transparent microspherical fillers (B) having a refractive index different by at least 5% from the refractive index of the lenses (A).
    Type: Grant
    Filed: September 25, 1995
    Date of Patent: March 10, 1998
    Assignee: Nippon Carbide Kogyo Kabushiki Kaisha
    Inventors: Katsura Ochi, Osamu Tanaka, Makoto Takeda
  • Patent number: 5679435
    Abstract: A retro-reflective vision control panel which includes an opaque sheet material coated with retro-reflective light reflecting particles and a dark opaque color on the reverse side thereof, and an image formed over top the retro-reflective particles using colored light permeable translucent inks or films to form an image thereon. The opaque sheet and image have a plurality of perforations spaced thereover such that when the light level on the image side of said panel is slightly less than, equal to, or greater than that on the other side, an observer on the image side clearly sees the image while an observer on the other side sees through the panel without seeing any trace whatsoever of the image or design.
    Type: Grant
    Filed: February 8, 1996
    Date of Patent: October 21, 1997
    Inventor: Michael D. Andriash
  • Patent number: 5674605
    Abstract: A retroreflective applique is provided that includes a layer of optical lens elements partially embedded in and protruding from a transfer adhesive layer prepared from ingredients comprising a vinyl plastisol and a substantially nonhydrolyzed aminosilane adhesion promoter; wherein the aminosilane adhesion promoter is used in an amount effective to produce an applique capable of:(a) retaining at least about 60% of its initial retroreflectivity after being laminated to 65/35 polyester/cotton blend fabric (100 g/m.sup.2) at about 174.degree. C. and about 2.8 Kg/cm.sup.2 pressure for about 20 seconds and subjected to home laundering conditions five times; and(b) retaining at least about 40% of its initial retroreflectivity after being laminated to 65/35 polyester/cotton blend fabric (100 g/m.sup.2) at about 174.degree. C. and about 2.8 Kg/cm.sup.2 pressure for about 20 seconds and subjected to home laundering conditions twenty-five times.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: October 7, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Paul E. Marecki
  • Patent number: 5673148
    Abstract: Encapsulated retroreflective element comprising a retroreflective assembly made up of a transparent optical body and a reflective member and essentially completely encapsulated within a dense, substantially transparent oxide coating. Also a method for making such retroreflective elements and articles and compositions comprising such retroreflective elements.
    Type: Grant
    Filed: June 23, 1994
    Date of Patent: September 30, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Geoffrey P. Morris, Kenton D. Budd
  • Patent number: 5639530
    Abstract: Retroreflective articles for life saving devices at sea are described comprising a layer of a pressure-sensitive adhesive made using a solvent-free hot melt process which employs as starting material a tackified non-thermoplastic hydrocarbon elastomer. The process employs a continuous compounding device that has a sequence of alternating conveying and processing zones.
    Type: Grant
    Filed: June 16, 1995
    Date of Patent: June 17, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gary R. Miron, Thanh-Huong Thi Nguyen
  • Patent number: 5621571
    Abstract: An integrated retroreflective data communication display for visual and electromagnetic communication is described. The display may be configured as an integrated retroreflective electronic license plate, with printed visual information, similar to the information printed on traditional license plates, on retroreflective sheeting. An antenna network is integrated within the license plate for electromagnetic communication and may be connected to external electronic modules. The display may also be configured as an integrated retroreflective electronic road sign, also providing visual and electromagnetic information in a unitary structure.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: April 15, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Heinrich Bantli, Thomas I. Bradshaw, Stephen W. Mohn, Edmund J. Ring
  • Patent number: 5620775
    Abstract: This invention relates to glass microsphere (bead) coated articles having an upper surface comprising a layer of low refractive index transparent glass microspheres such as those made from recycled ordinary glass. The articles of the invention have an extremely smooth tactile feel and a low friction surface even though they can be prepared from glass microspheres intermixed with abrasive irregularly shaped glass particles. The invention also relates to the method making the bead coated articles of the invention and transfer articles that can be used to make the bead coated articles of the invention.
    Type: Grant
    Filed: November 3, 1995
    Date of Patent: April 15, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: James D. LaPerre
  • Patent number: 5605761
    Abstract: An article exhibiting durable fluorescent properties comprising a polymeric matrix, dye, and hindered amine light stabilizer, wherein the polymeric matrix is comprised of polycarbonate and the dye is comprised of a dye selected from the group consisting essentially of thioxanthone, perylene imide and/or thioindigoid compounds. The article exhibits durable fluorescence which resists degradation by ultraviolet or visible radiation. The invention is optionally combined with retroreflective elements so that the resultant article has durable fluorescent properties when exposed to sunlight and is also retroreflective. A method of manufacturing an article exhibiting durable fluorescent properties is also disclosed along with a method of increasing the durability of polycarbonate in a dyed system.
    Type: Grant
    Filed: May 21, 1996
    Date of Patent: February 25, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: David M. Burns, Lee A. Pavelka
  • Patent number: 5557461
    Abstract: A novel roadway or similar marker strip having preferably retro-reflective-beaded protuberances in a critical "herringbone"-like pattern that provides a surprising degree of azimuthal uniform omindirectionality of light reflected from the strip.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: September 17, 1996
    Assignee: BriteLine Industries, Inc.
    Inventor: Charles W. Wyckoff
  • Patent number: 5514441
    Abstract: Retroreflective sheeting having an aliphatic polyurethane topcoat is described. The aliphatic polyurethane topcoat is obtainable from a mixture comprising (A) an aliphatic polyurethane derived from an aliphatic polyisocyanate and a polyester polyol prepared from a mixture comprising (A-1) a dicarboxylic acid component comprising isophthalic acid as the major dicarboxylic acid; and (A-2) a polyol component; and (B) cellulose acetate butyrate. The mixture also may contain (C) at least one non-reactive solvent, and optionally, (D) one or more surfactants including, for example, hydroxy-containing non-silicone surfactants.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: May 7, 1996
    Assignee: Avery Dennison Corporation
    Inventors: Susan L. Pohto, Richard J. Katona, George H. Wise, Robert K. Rega
  • Patent number: 5502593
    Abstract: A low profile pavement marker having a glass bead type reflector and an inclined top surface is disclosed. Flanges extend from a peripheral surface on the face and from the rear of the reflector for engagement with epoxy for mounting the pavement marker to the road surface. The front face is angled to permit wiping of the glass beads of the reflector. The shell of the pavement marker may be trimmed to be combined with other shells or other reflectors.
    Type: Grant
    Filed: August 3, 1992
    Date of Patent: March 26, 1996
    Assignee: Pac-Tec, Inc.
    Inventor: Peter Hedgewick
  • Patent number: 5474827
    Abstract: A retroreflective article (100, 200, 300) includes a monolayer of retroreflective elements (120, 220, 320), a binder layer (110, 210, 310), and a compound comprising an aromatic bidentate moiety. The retroreflective elements (120, 220, 320) are partially embedded in the binder layer (110, 210, 310), and the compound is chemically associated with the retroreflective elements (120, 220, 320) to provide extraordinary laundering durability to the retroreflective article (100, 200, 300).
    Type: Grant
    Filed: March 23, 1994
    Date of Patent: December 12, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Michael D. Crandall, Allen L. Griggs, Peter M. Olofson, Taun L. McKenzie, Theresa M. Watschke
  • Patent number: 5468540
    Abstract: A retroreflective article comprising a transparent base sheet having first and second broad faces, the second face being substantially planar and the first face having an array of substantially hemi-spheroidal microlenses thereon, the microlenses being wider and shorter than portions of true spheres, the shape of the microlenses and thickness of the base sheet being such that collimated light substantially orthogonally incident to the array is focused approximately at the second face, wherein the second face has a coating of a nacreous pigment composition thereon. The article can include an optional layer of adhesive over the reflective layer to permit the article to be adhered to a document as a tamper-indicating, authenticating, and protective overlay. Special images can be formed within the article to enhance the security provided thereby. Also, a method for making such base sheets, and a method for making a forming master.
    Type: Grant
    Filed: July 29, 1993
    Date of Patent: November 21, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Shih-Lai Lu
  • Patent number: 5451447
    Abstract: Retroreflective appliques comprising a monolayer of retroreflective elements partially embedded in and protruding from the front surface of a binder layer and an optional layer of adhesive on the rear surface of the binder layer, wherein the binder layer, the adhesive layer, or both contain a metal-azo dye to camouflage the color of any exposed portions of said binder layer. Appliques comprising micropheres with aluminum reflectors as retroreflective elements and a black metal-azo dye in the binder layer will exhibit a pleasing silver appearance even after portions of the binder layer have been visibly exposed due to degradation of the aluminum reflectors, typically as a result of subjecting the applique to harsh laundering conditions.
    Type: Grant
    Filed: April 15, 1994
    Date of Patent: September 19, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Wu-Shyong Li
  • Patent number: 5422162
    Abstract: A conformable marking tape having improved mechanical properties comprises a support base and a top-coat layer, the support base comprising a highly saturated acrylonitrile elastomer grafted with a zinc salt of methacrylic acid. The top-coat layer preferably comprises a polyurethane resin having about 50 to about 65% by weight of rigid segments and about 35 to about 50% by weight of flexible segments. The rigid segments are derived from diisocyanates and aliphatic and/or cycloaliphatic chain extenders, and the flexible segments are derived from polymeric compounds having at least two active hydrogen atoms and having weight average molecular weights ranging from about 400 to about 4000.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: June 6, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Sergio Passarino, Luigi Cazzaniga
  • Patent number: 5417515
    Abstract: A retroreflective article and a method for making same are taught. The retroreflective article comprises transparent microspheres and both specular and diffuse reflective pigments dispersed in a binder layer. The utilization of both types of pigments results in improved retroreflectivity over a greater range of entrance angles than if only one or the other pigment alone were used.
    Type: Grant
    Filed: May 20, 1994
    Date of Patent: May 23, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Kathleen A. Hachey, Thomas P. Hedblom, David C. May
  • Patent number: 5387458
    Abstract: Article comprising an ultraviolet screening screen layer and a color layer containing a defined daylight fluorescent dye dissolved in a defined polymeric matrix. The article exhibits durable fluorescence and resistance to degradation from exposure to sunlight. If desired, the article is retroreflective.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: February 7, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Lee A. Pavelka, David M. Burns, Raymond P. Johnston, Edward S. Shinbach
  • Patent number: 5376431
    Abstract: Retroreflective sheet material is produced by forming sheet material with closely spaced retroreflective formations on one face and depositing on this face silver and copper atoms having high kinetic energy to provide a reflective metallic deposit comprising a base layer of metallic silver and an overlying layer of metallic copper. An organic protective coating is thereafter applied over the reflective metallic deposit. Light rays passing through the front face of the body enter the retroreflective formations, impinge upon the interface provided by the silver base layer and are retroreflected therefrom. As a result, the sheet material exhibits a bright white appearance in daylight as well as a bright white coloration at night when an incandescent beam impinges thereon.
    Type: Grant
    Filed: May 12, 1993
    Date of Patent: December 27, 1994
    Assignee: Reflexite Corporation
    Inventor: William P. Rowland
  • Patent number: 5338595
    Abstract: Retroreflective appliques comprising a monolayer of retroreflective elements partially embedded in and protruding from the front surface of a binder layer and an optional layer of adhesive on the rear surface of the binder layer, wherein the binder layer, the adhesive layer, or both contain a metal-azo dye to camouflage the color of any exposed portions of said binder layer. Appliques comprising micropheres with aluminum reflectors as retroreflective elements and a black metal-azo dye in the binder layer will exhibit a pleasing silver appearance even after portions of the binder layer have been visibly exposed due to degradation of the aluminum reflectors, typically as a result of subjecting the applique to harsh laundering conditions.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: August 16, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Wu-Shyong Li
  • Patent number: 5316838
    Abstract: A retroreflective sheet comprising a monolayer of retroreflective elements partially embedded in and partially protruding from the front surface of a binder layer and a backing bonded to the back surface of the binder layer wherein the backing is elastic and comprises a highly conformable and deformable nonwoven web comprising melt-blown microfibers having multiple layers of a relatively low modulus material and a high modulus material.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: May 31, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Michael D. Crandall, Eugene G. Joseph
  • Patent number: 5283101
    Abstract: Retroreflective appliques comprising a monolayer of retroreflective elements partially embedded in and protruding from the front surface of a binder layer and an optional layer of adhesive on the rear surface of the binder layer for securing the applique to a garment, wherein the binder layer comprises an electron-beam cured polymer selected from the group consisting of chlorosulfonated polyethylenes, ethylene copolymers comprising at least about 70 weight percent of polyethylene, and EPDM polymers.
    Type: Grant
    Filed: September 28, 1992
    Date of Patent: February 1, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Wu-Shyong Li