Patents by Inventor Jon A. Bjork

Jon A. Bjork has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20060032600
    Abstract: A composition for use in investment casting includes a pattern material. The pattern material has internal mold releasability. The composition is suitable for use in investment casting. The pattern material may include a wax, a resin, a filler, and/or a fluorochemical. The pattern material may be capable of being injected numerous consecutive times without requiring the application of an external mold release agent (such as spraying silicone release agent) to a die used in the investment casting process. The pattern material would preferably have sufficient mold releasability to not adhere to the die, but sufficient adhesion to adhere to a shell-forming material, such as a ceramic slurry.
    Type: Application
    Filed: August 10, 2004
    Publication date: February 16, 2006
    Inventor: Jon Bjork
  • Patent number: 5578548
    Abstract: A thermographic element containing: (a) a substrate; (b) an image-forming layer coated onto the substrate; and (c) overlaying the image-forming layer, a topcoat layer composed of the reaction product of (1) a polymer composed of interpolymerized units derived from: (i) about 45-65 wt % of vinyl-substituted aromatic monomer; (ii) about 15-30 wt % vinyl monomer containing a pendant nitrile group; (iii) about 5-30 wt % hydroxyl-containing; ethylenically-unsaturated monomer; and (2) a suitable crosslinking agent. A slip agent is optionally used. The topcoat layer provides a thermographic element with high gloss in the imaged areas; has excellent runnability with no chatter in the feed direction of the element; and exhibits no removal of topcoat which prevents formation of printhead-created voids in the imaged areas.
    Type: Grant
    Filed: October 16, 1995
    Date of Patent: November 26, 1996
    Assignee: Minnesota Mining & Manufacturing Company
    Inventors: Jon A. Bjork, Ramesh C. Kumar, John C. Haidos
  • Patent number: 5478614
    Abstract: A radiation thermally imageable, solid toner addressable article comprises a substrate having on at least one surface thereof a layer comprising a) a solid binder which can be converted to a supercooled liquid upon heating and subsequent cooling to room temperature, b) a dye which absorbs radiation (at the wavelength of the imaging device,, e.e., ultraviolet, visible [especially the red], and infrared wavelengths) and converts infrared radiation to thermal energy, and c) a fluorinated surfactant. A directly thermally addressable article does not require the radiation absorbable dye.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: December 26, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: David A. Morgan, Jon A. Bjork
  • Patent number: 4985392
    Abstract: The present invention provides an intensely colored thermographic medium useful for bar-coding applications which utilize near infrared scanning systems. The medium is formed of a substrate having on at least one surface thereof a coating comprising: a transparent film-forming binder, an organic solvent soluble catechol, a metal salt and colorant.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: January 15, 1991
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Jon A. Bjork
  • Patent number: 4808565
    Abstract: Thermographic materials are colorless when unexposed, but provide an intense dark image when thermally addressed. The materials comprise white ferric organophosphate, ferric organophosphinate, or ferric organophosphonate in a clear binder with a colorless catechol or polycatechol held in said binder in solid solution. The choice of substituents on the catechol nucleus can give a change in the color of the thermal image together and provide good near infrared absorption. Use of mixed catechols can give achromatic black images. These combinations of materials show high stability at ambient temperatures.
    Type: Grant
    Filed: July 7, 1987
    Date of Patent: February 28, 1989
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: David R. Whitcomb, Jon A. Bjork