Patents by Inventor Man C. Tam

Man C. Tam 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: 7414775
    Abstract: A display member having improved optical contrast and brightness. The display member includes bichromal capsules, an absorptive layer, an adhesive layer, a substrate and a top layer. The bichromal capsules form a close-packed monolayer configuration positioned on the absorptive layer. The adhesive layer is adjacent to the absorptive layer. The absorptive layer is formed on the substrate. The top layer is formed adjacent the adhesive layer. A method for producing a display member with high optical contrast and brightness. The method includes forming an absorptive layer on a substrate. A close-packed monolayer configuration of bichromal capsules is formed on the absorptive layer by exposing the absorptive layer to a plurality of bichromal capsules. A top layer is formed adjacent the adhesive layer.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: August 19, 2008
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Peter M. Kazmaier, Naveen Chopra
  • Patent number: 7294358
    Abstract: An anisotropic conductive film includes a release layer, an insulating adhesive matrix on the release layer, and conductive particles distributed in the matrix in a substantially uniform pattern. The film may also include a patterned adhesive layer on the release layer, so that the particles are positioned in a pattern that substantially corresponds to the pattern of the patterned adhesive layer.
    Type: Grant
    Filed: June 21, 2005
    Date of Patent: November 13, 2007
    Assignee: Xerox Corporation
    Inventor: Man C Tam
  • Patent number: 7235196
    Abstract: A method for producing a display capsule includes the following steps. A multichromal bead having at least two surfaces differing from each other in optical and electrical characteristics is formed. A dispersing agent on an outer surface of the multichromal bead is applied, preferably via spray coating. The multichromal bead is then encapsulated. The invention is also directed to a method for producing multichromal capsules. A multichromal bead having at least two surfaces differing from each other in optical and electrical characteristics and further includes a charge control additive. A dispersing agent is applied on an outer surface of the multichromal bead to prevent diffusion of the charge control additive from the multichromal bead. The multichromal bead is encapsulated at an encapsulation reaction temperature greater than 40° C.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: June 26, 2007
    Assignee: Xerox Corporation
    Inventors: Thomas E. Enright, San-Ming Yang, Ahmed Alzamly, Naveen Chopra, Man C. Tam
  • Patent number: 7078095
    Abstract: An anisotropic conductive film includes a release layer, an insulating adhesive matrix on the release layer, and conductive particles distributed in the matrix in a substantially uniform pattern. The film may also include a patterned adhesive layer on the release layer, so that the particles are positioned in a pattern that substantially corresponds to the pattern of the patterned adhesive layer.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: July 18, 2006
    Assignee: Xerox Corporation
    Inventor: Man C. Tam
  • Patent number: 6699570
    Abstract: A dynamic reimageable document or electric paper can be formed from ordinary substrates such as paper, transparencies or fabric by printing of microencapsulated Gyricon beads onto one or more discrete surface areas of the substrate. The substrate can include both fixed print regions formed by conventional fixed ink processes and dynamic reimageable regions formed by the Gyricon beads. The Gyricon beads are preferably bichromal and of contrasting colors, such as black/white so as to be changeable to display two states by selective application of electromagnetic force to the beads. By providing bichromal beads in differing color combinations, such as red/white and black/white, a multi-colored document can be achieved in which various fields of the document, representing text, images or graphics, may be in differing colors. Moreover, operations to perform both imaging or erasure can act on the discrete reimageable regions so that the versatility of the electric paper can be enhanced.
    Type: Grant
    Filed: November 6, 2001
    Date of Patent: March 2, 2004
    Assignee: Xerox Corporation
    Inventors: Naveen Chopra, Steven Georges, Peter M. Kazmaier, Sammy Y.H. Ro, Man C. Tam, Francisco E. Torres, Sophie V. Vandebroek
  • Publication number: 20030087068
    Abstract: A dynamic reimageable document or electric paper can be formed from ordinary substrates such as paper, transparencies or fabric by printing of microencapsulated Gyricon beads onto one or more discrete surface areas of the substrate. The substrate can include both fixed print regions formed by conventional fixed ink processes and dynamic reimageable regions formed by the Gyricon beads. The Gyricon beads are preferably bichromal and of contrasting colors, such as black/white so as to be changeable to display two states by selective application of electromagnetic force to the beads. By providing bichromal beads in differing color combinations, such as red/white and black/white, a multi-colored document can be achieved in which various fields of the document, representing text, images or graphics, may be in differing colors. Moreover, operations to perform both imaging or erasure can act on the discrete reimageable regions so that the versatility of the electric paper can be enhanced.
    Type: Application
    Filed: November 6, 2001
    Publication date: May 8, 2003
    Applicant: XEROX CORPORATION
    Inventors: Naveen Chopra, Steven Georges, Peter M. Kazmaier, Sammy Y.H. Ro, Man C. Tam, Francisco E. Torres, Sophie V. Vandebroek
  • Patent number: 6180297
    Abstract: Disclosed is a process which comprises (a) providing a migration imaging member comprising (1) a substrate, (2) an infrared or red light radiation sensitive layer comprising a pigment predominantly sensitive to infrared or red light radiation, and (3) a softenable layer comprising a softenable material, a charge transport material, and a photosensitive migration marking material predominantly sensitive to radiation at a wavelength other than that to which the infrared or red light sensitive pigment is predominantly sensitive; (b) uniformly charging the imaging member; (c) subsequent to step (b), uniformly exposing the charged imaging member to a source of activating radiation with a wavelength to which the migration marking material is sensitive, wherein a filter comprising the infrared or red light radiation sensitive pigment is situated between the radiation source and the imaging member; (d) subsequent to step (b), exposing the imaging member to infrared or red light radiation at a wavelength to which the
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: January 30, 2001
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Edward G. Zwartz
  • Patent number: 6124409
    Abstract: Disclosed is a process for preparing copolymers which comprises, in the order stated: (1) adding monomers containing unsaturated carbon-to-carbon bonds, a first polymerization initiator, a second polymerization initiator, and a solvent to a reaction vessel; (2) purging the resulting solution with an inert gas; (3) sealing the reaction vessel and pressurizing it by addition of an inert gas to a pressure of from about 20 to about 600 kilopascals over ambient atmospheric pressure; (4) maintaining the temperature within the pressurized reaction vessel at a temperature of from about 50 to about 100.degree. C. for a period of from about 60 to about 300 minutes; (5) thereafter maintaining the temperature within the pressurized reaction vessel at a temperature of from about 80 to about 115.degree. C.
    Type: Grant
    Filed: August 12, 1992
    Date of Patent: September 26, 2000
    Assignee: Xerox Corporation
    Inventors: T. Hwee Ng, Hadi K. Mahabadi, Man C. Tam, Gregory J. Kovacs, Eric M. Peters, Rafik O. Loutfy
  • Patent number: 5683840
    Abstract: Methods and techniques of electrically biasing and providing a ground for migration imaging members are disclosed. An electrically conductive contact is fixed to the migration imaging member, the electrically conductive contact connecting at least an electrically conductive layer of the migration imaging member to a ground to insure proper imaging. The contacts are fixed to the migration imaging member without having to remove a portion of the softenable layer along its edge to expose the electrically conductive layer of the migration imaging member as is the current practice.
    Type: Grant
    Filed: April 11, 1996
    Date of Patent: November 4, 1997
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Edward G. Zwartz, Daniel Bihon, Robert J. Kleckner
  • Patent number: 5672451
    Abstract: Disclosed is a migration imaging member which comprises (a) a substrate, (b) a conductive layer comprising indium tin oxide dispersed in a polymeric binder, (c) a siloxane film charge blocking layer comprising a hydrolysis reaction product of a silane of the formula ##STR1## wherein R.sub.1 is an alkylidene group, R.sub.2 and R.sub.3 are each, independent of the other, a hydrogen atom, an alkyl group, a phenyl group, or a poly(ethyleneamino) group, and R.sub.4, R.sub.5, and R.sub.6 are each, independent of the others, alkyl groups, said siloxane having reactive hydroxyl and ammonium groups attached to silicon atoms, and (d) a softenable layer comprising a softenable material and a photosensitive migration marking material. Optionally an antistatic layer comprising indium tin oxide dispersed in a polymeric binder is situated on the surface of the substrate spaced from the softenable layer.
    Type: Grant
    Filed: April 11, 1996
    Date of Patent: September 30, 1997
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Liqin Chen, Edward G. Zwartz, Daniel Bihon, Marie-Eve Perron
  • Patent number: 5576129
    Abstract: Disclosed is a migration imaging member comprising a substrate, a first softenable layer comprising a first softenable material and a first migration marking material contained at or near the surface of the first softenable layer spaced from the substrate, and a second softenable layer comprising a second softenable material and a second migration marking material. Also disclosed is a migration imaging process employing the aforesaid imaging member.
    Type: Grant
    Filed: December 9, 1994
    Date of Patent: November 19, 1996
    Assignee: Xerox Corporation
    Inventors: Edward G. Zwartz, Carol A. Jennings, Man C. Tam, Philip H. Soden, Arthur Y. Jones, Arnold L. Pundsack, Enrique Levy, Ah-Mee Hor, William W. Limburg, John F. Yanus, Damodar M. Pai, Dale S. Renfer
  • Patent number: 5563013
    Abstract: Disclosed is a process which comprises (1) providing a migration imaging member comprising a substrate, an infrared or red light radiation sensitive layer comprising a pigment predominantly sensitive to infrared or red light radiation, and a softenable layer comprising a softenable material, a charge transport material, and migration marking material predominantly sensitive to radiation at a wavelength other than that to which the infrared or red light sensitive pigment is predominantly sensitive contained at or near the surface of the softenable layer, said infrared or red light radiation sensitive layer being situated between the substrate and the softenable layer; (2) uniformly charging the imaging member; (3) subsequent to step (2), uniformly exposing the imaging member to activating radiation at a wavelength to which the migration marking material is sensitive; (4) subsequent to step (3), neutralizing charge on the surface of the imaging member spaced from the substrate; (5) subsequent to step (4), expos
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: October 8, 1996
    Assignee: Xerox Corporation
    Inventor: Man C. Tam
  • Patent number: 5554470
    Abstract: A process and apparatus for preparing migration imaging members are disclosed. Two substrates with softenable layers applied to them travel through a vacuum chamber where they are simultaneously exposed to vapor deposition of the migration marking material. After the migration marking material is deposited, the two softenable layers are laminated together in the same vacuum chamber to form the migration imaging member. In one of the embodiments, the softenable layers are applied to the substrates in the same sweep of the substrate through the vacuum chamber vapor deposition and lamination steps.
    Type: Grant
    Filed: May 2, 1995
    Date of Patent: September 10, 1996
    Assignee: Xerox Corporation
    Inventors: Hardy Sonnenberg, Arnold L. Pundsack, Man C. Tam
  • Patent number: 5538825
    Abstract: Disclosed is a process which comprises (a) providing a migration imaging member which comprises a substrate and a softenable layer comprising a softenable material and a photosensitive migration marking material; (b) providing a printing plate precursor which comprises a base layer and a layer of photosensitive material selected from the group consisting of photohardenable materials and photosoftenable materials; (c) placing the softenable layer of the migration imaging member in contact with the layer of photosensitive material of the printing plate precursor and applying heat and pressure to the migration imaging member and printing plate precursor, thereby causing the softenable layer of the migration imaging member to adhere to the layer of photosensitive material of the printing plate precursor; (d) uniformly charging the migration imaging member; (e) subsequent to step (d), exposing the charged imaging member to activating radiation at a wavelength to which the migration marking material is sensitive; (
    Type: Grant
    Filed: October 2, 1995
    Date of Patent: July 23, 1996
    Assignee: Xerox Corporation
    Inventors: Arnold L. Pundsack, Hardy Sonnenberg, Man C. Tam
  • Patent number: 5411825
    Abstract: Disclosed is an apparatus for heat development of a migration imaging member containing migration marking material and a softenable material capable of softening upon exposure to heat at a development temperature, which apparatus comprises a heating source, a conveyance means for conveying the migration imaging member past the heating source, a first pinch roller in contact with the conveyance means, and a second pinch roller in contact with the conveyance means, wherein the imaging member passes through a nip between the conveyance means and the first pinch roller subsequent to entering the apparatus and prior to exposure to the heating source and passes through a nip between the conveyance means and the second pinch roller subsequent to exposure to the heating source and prior to exiting the apparatus, wherein the surface temperature of the first pinch roller is maintained at a temperature at least 20.degree. C.
    Type: Grant
    Filed: October 16, 1990
    Date of Patent: May 2, 1995
    Assignee: Xerox Corporation
    Inventor: Man C. Tam
  • Patent number: 5215838
    Abstract: Disclosed is a migration imaging member comprising a substrate, an infrared or red light radiation sensitive layer comprising a pigment predominantly sensitive to infrared or red light radiation, and a softenable layer comprising a softenable material, a charge transport material, and migration marking material predominantly sensitive to radiation at a wavelength other than that to which the infrared or red light radiation sensitive pigment is sensitive contained at or near the surface of the softenable layer. When the migration imaging member is imaged and developed, it is particularly suitable for use as a xeroprinting master and can also be used for viewing or for storing data.
    Type: Grant
    Filed: October 4, 1991
    Date of Patent: June 1, 1993
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Judith P. Meester, Hany M. Aboushaka, Rafik O. Loutfy, Gregory J. Kovacs, Carol A. Jennings
  • Patent number: 5202206
    Abstract: Disclosed is an imaging process for simultaneous printing of fixed and variable data which comprises, in the order states, (1) providing a migration imaging member comprising a substrate, a softenable layer comprising a softenable material and migration marking material contained at or near the surface of the softenable layer, and a charge transport material capable of transporting charges of one polarity; (2) uniformly charging the imaging member; (3) exposing the charged imaging member to activating radiation in an imagewise pattern corresponding to the fixed data, thereby forming an electrostatic latent image on the imaging member; (4) thereafter causing the softenable material to soften by the application of heat, thereby enabling the migration marking material exposed to radiation to migrate through the softenable material toward the substrate in an imagewise pattern corresponding to the fixed data; (5) uniformly charging the imaging member to the same polarity as the polarity of the charges that the cha
    Type: Grant
    Filed: October 4, 1991
    Date of Patent: April 13, 1993
    Assignee: Xerox Corporation
    Inventor: Man C. Tam
  • Patent number: 5102756
    Abstract: Disclosed is a printing plate precursor which comprises a base layer, a layer of photohardenable material, and a layer of softenable material containing photosensitive migration marking material. Alternatively, the precursor can comprise a base layer and a layer of softenable photohardenable material containing photosensitive migration marking material. Also disclosed are processes for preparing printing plates from the disclosed precursors.
    Type: Grant
    Filed: December 31, 1990
    Date of Patent: April 7, 1992
    Assignee: Xerox Corporation
    Inventors: Paul S. Vincett, Rafik O. Loutfy, Gregory J. Kovacs, Man C. Tam, Ronald Forstinger, Brian D. Lesser, Arnold L. Pundsack, Christopher Rodgers, Philip H. Soden
  • Patent number: 4970130
    Abstract: Disclosed is a xeroprinting process which comprises(1) providing a xeroprinting master comprising(a) a substrate; and(b) a softenable layer comprising a softenable material, a charge transport material capable of transporting charges of one polarity, and migration marking material situated contiguous to the surface of the softenable layer spaced from the substrate, wherein a portion of the migration marking material has migrated through the softenable layer toward the substrate in imagewise fashion;(2) uniformly charging the xeroprinting master to a polarity opposite to the polarity of the charges that the charge transport material in the softenable layer is capable of transporting;(3) uniformly exposing the charged master to activating radiation, thereby discharging those areas of the master wherein the migration marking material has migrated toward the substrate and forming an electrostatic latent image;(4) developing the electrostatic latent image; and(5) transferring the developed image to a receiver shee
    Type: Grant
    Filed: December 1, 1989
    Date of Patent: November 13, 1990
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Rafik O. Loutfy, Gregory J. Kovacs
  • Patent number: 4937163
    Abstract: An imaging member comprised of an ionically conductive film forming polymer, such as sulfonated polystyrene, and an electrically insulating softenable layer comprising a fracturable layer containing electrically photosensitive migration marking particles.
    Type: Grant
    Filed: January 27, 1989
    Date of Patent: June 26, 1990
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Arnold L. Pundsack