Patents by Inventor John Philip Tatum

John Philip Tatum 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: 10583651
    Abstract: A droplet deposition head having a fluid chamber connected to a droplet ejection nozzle and to a reservoir for the fluid, and a piezoelectric actuator element formed at least in part by a fluid chamber wall having an electrode thereon, which element is displaceable in response to a drive voltage to generate a pressure in the chamber to eject a droplet of fluid from the chamber through the nozzle wherein the electrode is provided with a passivation coating which comprises, at least in part, a laminate comprising an inorganic insulating layer nearest to or contacting the electrode and an organic insulating layer overlying the inorganic insulating layer wherein defects in the insulating layers tend to be misaligned at the interface there between and wherein the inorganic insulating layer has thickness less than or equal to 500 nm and the organic insulating layer has a thickness less than 3 ?m.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: March 10, 2020
    Assignee: XAAR TECHNOLOGY LIMITED
    Inventors: Song-Won Ko, Peter Mardilovich, John Philip Tatum, Alexandru Cazacu
  • Publication number: 20190030885
    Abstract: A droplet deposition head having a fluid chamber connected to a droplet ejection nozzle and to a reservoir for the fluid, and a piezoelectric actuator element formed at least in part by a fluid chamber wall having an electrode thereon, which element is displaceable in response to a drive voltage to generate a pressure in the chamber to eject a droplet of fluid from the chamber through the nozzle wherein the electrode is provided with a passivation coating which comprises, at least in part, a laminate comprising an inorganic insulating layer nearest to or contacting the electrode and an organic insulating layer overlying the inorganic insulating layer wherein defects in the insulating layers tend to be misaligned at the interface there between and wherein the inorganic insulating layer has thickness less than or equal to 500 nm and the organic insulating layer has a thickness less than 3 ?m.
    Type: Application
    Filed: December 22, 2016
    Publication date: January 31, 2019
    Inventors: Song-Won Ko, Peter Mardilovich, John Philip Tatum, Alexandru Cazacu
  • Patent number: 6476096
    Abstract: An ink jet printer ink is provided in the form of a non-aqueous dispersion of colorant in a diluent and containing a dispersant for the colorant and which yields print having no discernible odor. The diluent comprises more than 50% by volume of white oil and the dispersant, which is employed in an amount of at least 20% by weight of the colorant, comprises at least one compound having both a long chain aliphatic group and at least one &agr;, &bgr;-dicarboxylic acid moiety, e.g. a polyisobutylene succinimide.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: November 5, 2002
    Assignee: Xaar Technology Limited
    Inventors: Stuart Molloy, John Philip Tatum
  • Patent number: 6379440
    Abstract: Ink jet printer dispersion inks are provided which contain a dispersant having basic or acid groups and a non-destabilizing amount of a neutralizer for said groups. The inks exhibit improved non-wetting characteristics leading to lengthening of the duration of periods of continuous printing that can be achieved before cleaning or replacement of the nozzle plate of the ink jet print head is required.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: April 30, 2002
    Assignee: Xaar Technology Limited
    Inventors: John Philip Tatum, Jill Woods, Mary Catherine Ambrose Griffin
  • Patent number: 6162289
    Abstract: Ink jet printer dispersion inks are provided which contain a dispersant having basic or acid groups and a non-destabilizing amount of a neutralizer for said groups. The inks exhibit improved non-wetting characteristics leading to lengthening of the duration of periods of continuous printing that can be achieved before cleaning or replacement of the nozzle plate of the ink jet print head is required.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: December 19, 2000
    Assignee: Xaar Technology Limited
    Inventors: John Philip Tatum, Jill Woods, Mary Catherine Ambrose Griffin
  • Patent number: 5910372
    Abstract: A coating on a substrate which endows the substrate with a desired surface property, the coating comprising a cross-linked polysiloxane containing X'-- and X-groups attached to different Si atoms wherein the groups X'-- are monovalent organic groups which provide the desired surface property and the groups X-- are monovalent organic groups which are reactive with a group on the substrate surface and have a higher surface tension than the groups X'--, said coating being bonded to said substrate by reaction of X-groups with substrate surface groups reactive therewith. In one embodiment a non-wetting coating is provided wherein the X'-- group has the formula CF.sub.3 Z-- where Z is a divalent organic group or the formula CH.sub.3 (CH.sub.2).sub.t where t is at least 3.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: June 8, 1999
    Assignee: Xaar Technology Limited
    Inventors: Mary Catherine Ambrose Griffin, Leslie George Howarth, John Philip Tatum
  • Patent number: 5843219
    Abstract: A dispersion ink for ink jet printing and which is stable and produces good quality print on plain paper for extended periods of time without the need to interrupt printing to clean the print head, comprises a diluent containing a non-polar component, a pigment and a dispersant for stabilizing the dispersion of the pigment in the diluent, and has a polar solubility parameter greater than 0 but not greater than 7.0 MPa.sup.1/2 and a dewetting velocity of at least 100 .mu.m.sec.sup.-1, measured on a surface having a surface energy of 10.+-.1 mN.m.sup.-1.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: December 1, 1998
    Assignee: Xaar Technology Limited
    Inventors: Mary Catherine Ambrose Griffin, John Philip Tatum, Jill Woods
  • Patent number: 5837046
    Abstract: An ink jet printer ink of the kind comprising a dispersion of a pigment in a non-aqueous diluent wherein the diluent is a single phase liquid comprising a major amount of aliphatic hydrocarbon and a minor amount of a polar component, comprising oleyl alcohol alone or in combination with a least one other polar liquid such as an ether or an ester.
    Type: Grant
    Filed: July 23, 1997
    Date of Patent: November 17, 1998
    Assignee: Xaar Technology Limited
    Inventors: John David Schofield, John Philip Tatum, Jill Woods