Patents Represented by Attorney R. R. Tamte
  • Patent number: 4547420
    Abstract: Bicomponent fibers, and webs made therefrom, are taught in which one component of the fibers is a crystallizable material. When a web of the fibers is heated in a mold above the temperature at which crystallization occurs, the fibers tend to be set in the position they are held in the mold. A preferred fiber comprises blown fibers comprising as one component amorphous, crystallizable polyethylene terephthalate, and as the other component polypropylene. A web of such fibers not only becomes formed into a shape-retaining form by crystallization during the molding process, but also can be further established in its shape-retaining character by heating the web above the softening point of the polypropylene, whereupon the fibers become bonded at their points of intersection.
    Type: Grant
    Filed: October 11, 1983
    Date of Patent: October 15, 1985
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Dennis L. Krueger, Daniel E. Meyer
  • Patent number: 4511210
    Abstract: New methods for making "embedded-lens" retroreflective sheeting, and new forms of such sheeting, are provided. The new methods involve embedding microspheres into a web by continuously presenting a mass of the microspheres against the moving web and heating the web so as to soften at least an exterior stratum of the web, and adding a spacing layer to the microsphere-covered surface of the web. The microspheres are embedded on the average to less than 50 percent of their diameter, which has been found to cause the spacing layer to conform around a greater proportion of the back surface of individual microspheres and thereby position a greater portion of the specularly reflective layer carried on the spacing layer at the approximate focal point for light passed through the microspheres. Use of a preformed spacing layer also contributes to maintaining the spacing layer at a constant thickness around the back surface of the microspheres.
    Type: Grant
    Filed: September 16, 1983
    Date of Patent: April 16, 1985
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Chi F. Tung, James C. Coderre
  • Patent number: 4505967
    Abstract: A new embedded-lens retroreflective sheeting which exhibits superior properties, including superior angularity, and which is made by a new method of manufacture involving lamination techniques. Microspheres are embedded into a first polymeric layer to less than one-half the average diameter of the microspheres, and a pre-formed spacing film is laminated to the microsphere covered surface of the first layer so as to obtain conformation of the spacing film in a substantially constant thickness over a useful portion of the back surface of the microspheres.
    Type: Grant
    Filed: April 11, 1983
    Date of Patent: March 19, 1985
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Terry R. Bailey
  • Patent number: 4490432
    Abstract: Pavement-marking sheet material which comprises a non-crosslinked elastomeric precursor such as acrylonitrile-butadiene polymer; a thermoplastic polymer such as polyethylene which reinforces the sheet material, e.g., by orientation of the thermoplastic polymer so that the calendered product exhibits greater tensile strength downweb than crossweb; and a particulate inorganic filler, which preferably includes platelet-type fillers such as talc, mica, or magnesium silicate.
    Type: Grant
    Filed: November 1, 1983
    Date of Patent: December 25, 1984
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Stanley J. Jordan
  • Patent number: 4433024
    Abstract: Vapor-sorbing particle-filled sheet material having a low insulation value and useful for providing reduced-stress vapor-sorbing garments. The sheet material comprises at least one permeable support fabric attached to a fibrous web which comprises a coherent mass of melt-blown fibers and vapor-sorptive particles dispersed in the mass of fibers.
    Type: Grant
    Filed: July 23, 1982
    Date of Patent: February 21, 1984
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Gilbert L. Eian
  • Patent number: 4432172
    Abstract: Timber support poles are given desired breaking properties to reduce the deceleration of a vehicle that collides with the pole by cutting one or more recesses in the pole, and filling the recesses with a polymeric filler composition.
    Type: Grant
    Filed: January 11, 1982
    Date of Patent: February 21, 1984
    Assignee: Minnesota Mining & Manufacturing Company
    Inventors: Charles R. Kuykendall, Richard B. Castle
  • Patent number: 4429001
    Abstract: New sorbent sheet products are prepared comprising a coherent web of entangled blown fibers prepared by extruding liquid fiber-forming material into a high-velocity gaseous stream and an array of super absorbent polymeric particles dispersed within the web.
    Type: Grant
    Filed: March 4, 1982
    Date of Patent: January 31, 1984
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Barbara E. Kolpin, David C. Brownlee
  • Patent number: 4397142
    Abstract: Coded threads and sheet material for making such threads useful in counterfeit-inhibiting garments. The sheet material comprises transparent microspheres, a specularly reflective layer underlying the microspheres, and a polymeric layer underlying the specularly reflective layer and containing particulate matter which may be varied from sheet material to sheet material to encode information and allow identification of the sheet material. The sheet material is split in narrow widths and incorporated into threads.
    Type: Grant
    Filed: December 7, 1981
    Date of Patent: August 9, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Wallace K. Bingham
  • Patent number: 4393901
    Abstract: Pipe adapted to be installed underwater at increased ocean depths by practical pipe-laying procedures comprises a porous cement shell filled with hollow spheres that are slowly permeable to water under pressure. The cement shell is filled with a sufficient volume of the hollow spheres to make the pipe only slightly heavier than sea water, providing a reduced weight that overcomes previous difficulties in laying pipe at great depths. Over a period of time after the pipe has been installed underwater, the hollow spheres gradually fill with water and make the pipe rest stably on the ocean bottom. The preferred spheres comprise porous core spheres coated with thin coatings that partially seal the spheres to the needed degree of permeability.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: July 19, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Warren R. Beck
  • Patent number: 4391646
    Abstract: Glass bubbles of increased collapse strength are prepared. The bubbles have an average particle density of 0.4 or more and are made of glass that consists essentially of SiO.sub.2 (60-90 weight-percent), alkali metal oxide (2-20 weight-percent), B.sub.2 O.sub.3 (1-30 weight-percent), sulfur (0.005 to 0.5 weight-percent), and other conventional glass-forming ingredients.
    Type: Grant
    Filed: February 25, 1982
    Date of Patent: July 5, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Peter A. Howell
  • Patent number: 4388359
    Abstract: Pavement-marking sheet material having protuberances on its upper surface which carry partially exposed microspheres by which the protuberances are made retroreflective and which are separated by recessed areas in which microspheres are fully embedded and not exposed, so as to improve the daytime appearance of the sheet material.
    Type: Grant
    Filed: April 23, 1982
    Date of Patent: June 14, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: John L. Ethen, Timothy D. Bredahl
  • Patent number: 4377988
    Abstract: Reflective sheeting useful for application to a pesticide-impregnated animal collar, and animal collars made from the sheeting. The sheeting generally comprises a monolayer of transparent microspheres; specularly reflective material underlying the microspheres; a binder layer of polymeric binder material in which the microspheres are partially embedded; a carrier sheet stretchable about 10 percent or more before rupture, in which the portions of the microspheres protruding from the binder layer are embedded; a barrier layer underlying the binder layer, which sorbs plasticizers more slowly than the binder layer sorbs the plasticizers; and a layer of adhesive underlying the barrier layer.
    Type: Grant
    Filed: September 24, 1981
    Date of Patent: March 29, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Chi F. Tung, James C. Coderre, Chester A. Bacon, Jr.
  • Patent number: 4372997
    Abstract: Fire- and heat-resistant sheet material comprises fibrous webs adhered together with asphalt which is filled with inorganic particles, intumescable granules, and a catalyst which catalyzes charring of the asphalt.
    Type: Grant
    Filed: April 9, 1982
    Date of Patent: February 8, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gary D. Fritze, Joseph Graham
  • Patent number: 4367920
    Abstract: New methods for making "embedded-lens" retroreflective sheeting, and new forms of such sheeting, are provided. The new sheetings are retroreflective through an increased angular range, and also provide brighter overall retroreflectivity and other advantageous properties.
    Type: Grant
    Filed: June 19, 1981
    Date of Patent: January 11, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Chi F. Tung, James C. Coderre
  • Patent number: 4367919
    Abstract: Glass microspheres and other glass elements based on B.sub.2 O.sub.3, BaO, SiO.sub.2 and TiO.sub.2 have an improved combination of crushing strength, index of refraction, and, especially in some formulations, chemical resistance. The microspheres are especially adapted for use as retroreflective elements in pavement markings.
    Type: Grant
    Filed: March 19, 1981
    Date of Patent: January 11, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Chi F. Tung, Benjamin T. Fellows
  • Patent number: 4349598
    Abstract: Retroreflective film, sheeting or the like having an array of light-reflecting right triangle prisms between a transparent surface layer and a backing layer. The opposing triangular end faces of adjacent prisms are spaced apart to provide internal reflection therefrom. The retroreflective material provides efficient retroreflection at angles of incidence of about 30.degree.-85.degree. and therefore is effective where light is directed in a path nearly parallel to a reflective surface, such as highway lane dividers or guardrail markers placed parallel to a highway. Retroreflective material on such markers becomes visible to an observer while yet remote from the markers.
    Type: Grant
    Filed: December 1, 1976
    Date of Patent: September 14, 1982
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Michael L. White
  • Patent number: 4348312
    Abstract: Compositions comprising copolymers of methyl methacrylate and ethyl acrylate and of vinylidene fluoride and hexafluoropropylene may be blended to form transparent compositions of low refractive index, making them useful in retroreflective products as a layer in which glass microspheres are embedded.
    Type: Grant
    Filed: March 11, 1981
    Date of Patent: September 7, 1982
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Chi F. Tung
  • Patent number: 4312676
    Abstract: A liquid coating composition that is useful to form retro-reflective marks that actuate photoscanner sensing devices and that comprises a liquid vehicle and retro-reflective elements uniformly dispersed in the vehicle. The vehicle includes a high proportion of volatile solvent and a gel agent that gels the vehicle so that the retro-reflective elements are suspended in the vehicle. The gel agent comprises at least a large proportion of the non-volatile portion of the vehicle.
    Type: Grant
    Filed: August 26, 1977
    Date of Patent: January 26, 1982
    Assignee: Minnesota Mining & Manufacturing Company
    Inventors: John M. Hogseth, Melvin L. Johnson
  • Patent number: RE31087
    Abstract: A method for separating water-immiscible oils and oil-like substances from mixtures including said oils in an aqueous medium which comprises contacting the mixture with an oleophilic fibrous web comprising large numbers of interconnected, interstitial spaces for reception and retention of the oil to the exclusion of water.
    Type: Grant
    Filed: April 16, 1981
    Date of Patent: November 23, 1982
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: William E. Sohl
  • Patent number: RE31285
    Abstract: A method for forming a filter of electrically charged electret fiber material, consisting of a high molecular weight, nonpolar polymeric substance, comprising drawing, charging, and fibrillating a foil of said high molecular weight substance. The fibrillated foil is wound and then crimping is effected.
    Type: Grant
    Filed: December 7, 1981
    Date of Patent: June 21, 1983
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Jan van Turnhout, Johannes C. Rieke