Patents by Inventor John David Schofield

John David Schofield 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: 7732514
    Abstract: A composition comprising a plastics material, an inorganic particulate solid such as aluminium trihydrate and a coupling modified of formula A-(X—Y—CO)m(O—B—CO)nOH wherein A is a moiety containing a terminating ethylenic group with one or two adjacent carbonyl groups; X is a direct bond, O or N; Y is C1-18-alkylene or C2-18-alkenylene; B is C2-6-alkylene; m is from 1 to 4 and n is from 0 to 5 provided that when A contains two carbonyl groups adjacent to the ethylenic group then X is N. Specific examples of coupling modifiers are ?-carboxyl ethylacrylate and 5-carboxy pentyl maleimide.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: June 8, 2010
    Assignee: The Lubrizol Corporation
    Inventors: Roger Norman Rothon, Dean Thetford, Stuart Nicholas Richards, John David Schofield
  • Patent number: 7442327
    Abstract: Dispersions useful in making capacitors, printed circuit boards, etc., comprising an electronic particulate solid, a carrier and a dispersant of formula (1): R—(O-A-CO)x(O—B—CO)y-Z wherein R is hydrogen or a polymerisation terminating group; A is C8-20-alkylene and/or C8-20-alkenylene; B is C1-6-alkylene or a lactone thereof; Z is hydroxyl or a basic group or a moiety containing a basic group; x is from 2 to 45; Y is from 0 to 15; and the ration of x:y is not less than 3:1, the carrier is a high boiling organic liquid having a boiling point between 150 and 350° C. selected from monohydric alcohols and esters of dialkylene glycol monoalkyl esters.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: October 28, 2008
    Assignee: The Lubrizol Corporation
    Inventors: Dean Thetford, John David Schofield
  • Patent number: 7095044
    Abstract: A field effect transistor in which a continuous semiconductor layer comprises: a) an organic semiconductor; and, b) an organic binder which has an inherent conductivity of less than 10?6Scm?1 and a permittivity at 1,000 Hz of less than 3.3 and a process for its production comprising: coating a substrate with a liquid layer which comprises the organic semiconductor and a material capable of reacting to form the binder; and, converting the liquid layer to a solid layer comprising the semiconductor and the binder by reacting the material to form the binder.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: August 22, 2006
    Assignee: Merck Patent GmbH
    Inventors: Beverley Anne Brown, Domenico Carlo Cupertino, Janos Veres, John David Schofield, Stephen William Leeming, Stephen George Yeates
  • Patent number: 7008988
    Abstract: A paint comprising a film-forming resin, an organic liquid, a pigment and a dispersant of formula 1, including salts thereof (T-(O-A-CO)n(O-B-CO)mpZ wherein T is H or a polymerisation terminating group; A is C16-20-alkenylene; B is C10-20-alkylene; Z is the residue of a polyamine or polyimine; n is 2 to 50; m is 0 to 25; and p is not less than 2. Preferred dispersants are derived from poly(ricinoleic acid) and polyethylene imine.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: March 7, 2006
    Assignee: The Lubrizol Corporation
    Inventors: Dean Thetford, John David Schofield
  • Patent number: 6770704
    Abstract: The use of an amine functional polymer, including salts thereof, as a rheology modifier for solvent-based paints, inks, filled thermosetting resins and thermosetting resin-based gelcoats whereby the amine functional polymer contains not less that 42% by weight of the residue of one or more amine-containing monomers, or salts thereof, relative to the weight of the polymer. Preferably the amine functional polymer is obtainable from two or more monomers which contain at least one ethylenically unsaturated group such as styrene and 2-dimethylaminoethylmethacrylate.
    Type: Grant
    Filed: December 5, 2002
    Date of Patent: August 3, 2004
    Assignee: Avecia Limited
    Inventors: David John Cartridge, Dean Thetford, John David Schofield, Paul Gough, Stuart Nicholas Richards
  • Publication number: 20040116568
    Abstract: A paint comprising a film-forming resin, an organic liquid, a pigment and a dispersant of formula 1, including salts thereof
    Type: Application
    Filed: January 23, 2004
    Publication date: June 17, 2004
    Inventors: Dean Thetford, John David Schofield
  • Publication number: 20040038459
    Abstract: A field effect transistor in which a continuous semiconductor layer comprises:
    Type: Application
    Filed: May 6, 2003
    Publication date: February 26, 2004
    Inventors: Beverley Anne Brown, Domenico Cupertino, Janos Veres, John David Schofield, Stephen William Leeming, Stephen George Yeates
  • Publication number: 20030171485
    Abstract: The use of an amine functional polymer, including salts thereof, as a rheology modifier for solvent-based paints, inks, filled thermosetting resins and thermosetting resin-based gelcoats whereby the amine functional polymer contains not less that 42% by weight of the residue of one or more amine-containing monomers, or salts thereof, relative to the weight of the polymer. Preferably the amine functional polymer is obtainable from two or more monomers which contain at least one ethylenically unsaturated group such as styrene and 2-dimethylaminoethylmethacrylate.
    Type: Application
    Filed: December 5, 2002
    Publication date: September 11, 2003
    Inventors: David John Catridge, Dean Thetford, John David Schofield, Paul Gough, Stuart Nicholas Richards
  • Patent number: 6197877
    Abstract: A dispersant of general Formula I T—(A)n(B)p—Z   (1) wherein T is hydrogen or a polymerisation terminating group; Z is an acidic or basic group or a moiety containing either an acidic or basic group; A and B are each, independently, oxyalkylene carbonyl groups derivable from &dgr;-valerolactone, &egr;-caprolactone or alkyl substituted &egr;-caprolactone provided that both are not &egr;-caprolactone or &dgr;-valerolactone; n and p are integers; and n+p is from 2 to 100; including salts thereof. Specific examples of dispersants are the reaction product of lauric acid, &dgr;-caprolactone, 7-methyl-&egr;-caprolactone with PEI, the reaction product of lauric acid, &egr;-caprolactone, &dgr;-valerolactone with PEI and the phosphate of the reaction product of dodecanol, &egr;-caprolactone and &dgr;-valerolactone.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: March 6, 2001
    Assignee: Zeneca Limited
    Inventors: Dean Thetford, John David Schofield, Patrick John Sunderland
  • Patent number: 6197103
    Abstract: A composition of copper phthalocyanines containing, on average, from 0.1 to 3 methyl groups per phthalocyanine nucleus. The composition is suitable for the coloration of paints and plastics materials.
    Type: Grant
    Filed: November 10, 1994
    Date of Patent: March 6, 2001
    Assignee: Zeneca Limited
    Inventors: Peter Kingsley Davies, John David Schofield, John Michael McCarthy
  • Patent number: 6191253
    Abstract: A dispersant for aqueous mill-bases obtainable by reacting a polyethylene glycol with a molar excess of a hydroxycarboxylic acid containing from 4 to 17 carbon atoms or lactone thereof and/or with a C3-4-alkylene oxide to form a polymeric diol and phosphating the diol. The preferred hydroxycarboxylic acid or lactone is &egr;-caprolactone.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: February 20, 2001
    Assignee: Zeneca Limited
    Inventors: John David Schofield, Dean Thetford
  • Patent number: 6117935
    Abstract: A rheology modifier for solvent-based coatings which is a polyacrylic acid or a poly(C.sub.1-4)-alkyl acrylic acid wherein at least 30% of the --COOH groups are converted to ester and/or amide groups. Preferred compounds are esters of polyacrylic acid where about 50% of the --COOH groups are esterified with a C.sub.4-12 -alcohol.
    Type: Grant
    Filed: April 4, 1997
    Date of Patent: September 12, 2000
    Assignee: Zeneca Limited
    Inventors: John David Schofield, Paul Gough
  • Patent number: 5954870
    Abstract: A composition of copper phthalocyanines containing, on average, from 0.1 to 3 methyl groups per phthalocyanine nucleus. The composition is suitable for the coloration of paints and plastics materials.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 21, 1999
    Assignee: Zeneca Limited
    Inventors: Peter Kingsley Davies, John David Schofield, John Michael McCarthy
  • 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
  • Patent number: 5785894
    Abstract: A dispersant for aqueous mill-bases obtainable by reacting a polyethylene glycol with a molar excess of a hydroxycarboxylic acid containing from 4 to 17 carbon atoms or lactone thereof and/or with a C.sub.3-4 -alkylene oxide to form a polymeric diol and phosphating the diol. The preferred hydroxycarboxylic acid or lactone is .epsilon.-caprolactone.
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: July 28, 1998
    Assignee: Zeneca Limited
    Inventors: John David Schofield, Dean Thetford
  • Patent number: 5753022
    Abstract: A method of preparing a non-aqueous dispersion of CuPc which comprises milling crude CuPc in a high boiling liquid at a temperature from 50.degree. to 150.degree. C. in the presence of a polyester amine or polyesterammonium salt and a CuPc fluidising agent. Preferred polyesterammonium salt is obtainable by reacting polyhydroxystearic acid with 3-dimethylaminopropylamine quaternised with dimethylsulphate.
    Type: Grant
    Filed: February 5, 1996
    Date of Patent: May 19, 1998
    Assignee: Zeneca Limited
    Inventors: John David Schofield, Dean Thetford
  • Patent number: 5700395
    Abstract: A dispersant comprising a polyethyleneimine residue carrying polyester chains derived from a caprolactone and at least one other specified lactone or hydroxycarboxylic acid.
    Type: Grant
    Filed: September 25, 1995
    Date of Patent: December 23, 1997
    Assignee: Zeneca Limited
    Inventors: Dean Thetford, John David Schofield
  • Patent number: RE44769
    Abstract: A dispersant of general Formula I T—(A)n(B)p—Z??(1) wherein T is hydrogen or a polymerisation terminating group; Z is an acidic or basic group or a moiety containing either an acidic or basic group; A and B are each, independently, oxyalkylene carbonyl groups derivable from ?-valerolactone, ?-caprolactone or alkyl substituted ?-caprolactone provided that both are not ?-caprolactone or ?-valerolactone; n and p are integers; and n+p is from 2 to 100; including salts thereof. Specific examples of dispersants are the reaction product of lauric acid, ?-caprolactone, 7-methyl-?-caprolactone with PEI, the reaction product of lauric acid, ?-caprolactone, ?-valerolactone with PEI and the phosphate of the reaction product of dodecanol, ?-caprolactone and ?-valerolactone.
    Type: Grant
    Filed: September 2, 2010
    Date of Patent: February 18, 2014
    Assignee: The Lubrizol Corporation
    Inventors: Dean Thetford, John David Schofield, Patrick John Sunderland