Patents by Inventor David C. Weigel

David C. Weigel 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).

  • Patent number: 5576074
    Abstract: A process is described for providing a conductive metal circuit using a coherent radiation source. The circuit pattern is directly written onto a laser addressable element having a supercooling material layer. A conductive metal toner is then applied to the light struck areas and fired in a furnace to provide a conductive metal circuit.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: November 19, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: David C. Weigel, David A. Morgan
  • Patent number: 5278024
    Abstract: A photothermographic composite structure for use in a solvent-free dye thermal positive imaging diffusion-transfer process comprising:(a) an image-receiving element comprising a polymeric dyeable image-receiving layer having a glass transition temperature in the range of 20.degree. to 200.degree. C., and(b) strippably adhered to said image-receiving element, an imageable photothermographic element comprising in at least one layer thereof a binder, a silver source material, photosensitive silver halide in catalytic proximity to said silver source material, and a formazan dye.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: January 11, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Richard C. Cotner, David C. Weigel, Kumars Sakizadeh
  • Patent number: 5275932
    Abstract: Thermal recording material containing a suitable substrate coated with an image forming layer. The image forming layer contains a thermally reducible source of silver, a 3-indazolinone or urea compound; a polymeric binder; and optionally, an auxiliary reducing agent and toner. Preferably, an anti-stick layer is coated on top of the imaging layer.The 3-indazolinone and urea compounds have been found to enhance the thermal image forming capability of thermal recording material.
    Type: Grant
    Filed: July 22, 1992
    Date of Patent: January 4, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: David C. Weigel, Oanh V. Pham
  • Patent number: 5206112
    Abstract: A photothermographic composite structure for use in a solvent-free dye thermal positive imaging diffusion-transfer process comprising:(a) an image-receiving element comprising a polymeric dyeable image-receiving layer having a glass transition temperature in the range of 20.degree. to 200.degree. C., and(b) strippably adhered to said image-receiving element, an imageable photothermographic element comprising in at least one layer thereof a binder, a silver source material, photosensitive silver halide in catalytic proximity to said silver source material, and a formazan dye.
    Type: Grant
    Filed: June 27, 1991
    Date of Patent: April 27, 1993
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Richard C. Cotner, David C. Weigel, Kumars Sakizadeh
  • Patent number: 5185231
    Abstract: Certain fluoran dyes have been found to be effective reducing agents for silver ion in dry silver constructions. The fluoran dyes have the following structure: ##STR1## wherein: R.sup.1 represents methyl or n-butyl;R.sup.2 represents n-butyl or cyclohexyl;R.sup.3 represents hydrogen, methyl, or methoxy; andR.sup.4 represents ##STR2## where X represents halogen (preferably chlorine); and a binder.
    Type: Grant
    Filed: August 26, 1991
    Date of Patent: February 9, 1993
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: David C. Weigel
  • Patent number: 5026633
    Abstract: Photothermographic dry silver emulsions containing a benzylidene lenco dye and a development accelerator provide a high density yellow image upon exposure to actinic radiation and thermal developing at a relatively low temperature and for a short period of time.
    Type: Grant
    Filed: July 27, 1989
    Date of Patent: June 25, 1991
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: David C. Weigel
  • Patent number: 4923792
    Abstract: A photothermographic element comprising:(A) a coating comprising a support bearing a photothermographic medium, the medium comprising a light sensitive silver halide in reactive association with a silver salt of an organic acid and a color generating reducing agent which is a leuco compound which is oxidizable by silver ions into a colored dye of the general formula: ##STR1## in which: n=0, 1 or 2,R.sup.1 represents H, CN, lower alkyl of 1 to 5 carbon atoms, aryl or COOR.sup.6 in which R.sup.6 is lower alkyl of 1 to 5 carbon atoms or aryl,R.sup.2 and R.sup.3 independently represent CN, NO.sub.2, COOR.sup.6, SO.sub.2 R.sup.6, CONHR.sup.6 in which R.sup.6 is as defined above or R.sup.2 and R.sup.3 together represent the necessary atoms to form a 5- or 6-membered carbocyclic or heterocyclic ring having ring atoms selected from C, N, O and S atoms, whch carbocyclic or heterocyclic rings possess at least one conjugated electron withdrawing substituent,R.sup.4 and R.sup.
    Type: Grant
    Filed: June 20, 1989
    Date of Patent: May 8, 1990
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Duncan M. A. Grieve, Stephen S. C. Poon, Tran V. Thien, Kumars Sakizadeh, David C. Weigel
  • Patent number: 4883747
    Abstract: A photothermographic element comprising a support bearing a photothermographic medium, the medium comprising a light sensitive silver halide in reactive association with a silver salt of an organic acid and a color generating reducing agent which is a leuco compound which is oxidisable by silver ions into a colored dye of the general formula: ##STR1## in which: n=0, 1 or 2,R.sup.1 represents H, CN, lower alkyl of 1 to 5 carbon atoms, aryl or COOR.sup.6 in which R.sup.6 is lower alkyl of 1 to 5 carbon atoms or aryl,R.sup.2 and R.sup.3 independently represent CN, NO.sub.2, COOR.sup.6, SO.sub.2 R.sup.6, CONHR.sup.6 in which R.sup.6 is as defined above or R.sup.2 and R.sup.3 together represent the necessary atoms to form a 5- or 6-membered carbocyclic or heterocyclic ring having ring atoms selected from C, N, O and S atoms, which carbocyclic or heterocyclic rings possess at least one conjugated electron withdrawing substituent,R.sup.4 and R.sup.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: November 28, 1989
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Duncan M. A. Grieve, Stephen S. C. Poon, Tran V. Thien, Kumars Sakizadeh, David C. Weigel
  • Patent number: 4795697
    Abstract: Alkyl ketazine dyes are stabilized by the presence of poly(vinyl chloride) and/or poly(vinylidene chloride) binders in photothermographic emulsions.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: January 3, 1989
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Kim M. Vogel, David C. Weigel, Roger A. Mader
  • Patent number: 4782010
    Abstract: The use of phenazine, phenoxazine and phenothiazine color forming developers in photothermographic dry silver emulsions provides a stable imaging system under both light and dark storage.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: November 1, 1988
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Roger A. Mader, David C. Weigel, Louis M. Leichter, Kristen A. Hoff
  • Patent number: 4587211
    Abstract: Certain effective leuco dyes for silver halide/silver salt/reducing agent photothermographic color imaging materials tend to bleach in the final image. The presently disclosed system of a syringaldazine and a stabilizing binder resin is more stable.
    Type: Grant
    Filed: February 1, 1985
    Date of Patent: May 6, 1986
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Takuzo Ishida, David C. Weigel
  • Patent number: 4585734
    Abstract: Certain effective toning systems for silver halide/silver salt/reducing agent photothermographic imaging materials tend to bleach the final image. The presently disclosed toning system of phthalazine and an active-hydrogen containing heterocyclic compound is more stable than some previous toners.
    Type: Grant
    Filed: February 1, 1985
    Date of Patent: April 29, 1986
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: David C. Weigel
  • Patent number: 4328181
    Abstract: Indicator material for monitoring personal exposure to hazardous substances in ambient air comprising a pigment material, a binder and a sensitizer coated upon a transparent support member as a porous coating which permits gaseous diffusion throughout the coating is disclosed. Detection or monitoring is effected when the indicator material undergoes a visually observable reaction with hazardous material in the atmosphere at room temperature.
    Type: Grant
    Filed: July 6, 1979
    Date of Patent: May 4, 1982
    Assignee: Minnesota Mining and Manufacturing Co.
    Inventors: Leon W. Anders, David C. Weigel