Patents by Inventor David W. Thornthwaite

David W. Thornthwaite 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: 6727382
    Abstract: Cationic peroxyacids of formula (IV) wherein: R1 is a, optionally substituted, C1-C7 alkyl or alkenyl or alkaryl with a C1-C7 alkyl group; R2 and R3 are each independently a C1-C3 alkyl or C1-C3 substituted alkyl group; n is an integer from 0 to 3; and X− is a surfactant anion selected from alkyl carboxylates; alkyl ether sulphates; alkylbenzene sulphonates; C12-15 primary and C14-18 secondary alkyl sulphates; olefin sulphonates; alkane sulphonates; dialkyl sulphosuccinates; fatty acid ester sulphonates; alkylether sulphonates, alkylether carboxylates, sulphonated alkyl polyglycosides; sulphonated alkanoyl glucose ethers, sulphonated monoglycerol ethers; secondary alkane sulphonates; esterified isethionates; alkyl and dialkyl phosphates; sodium fatty acid sulphonates; and fatty acid soaps. They can be used in bleaching and detergent compositions and in bleach additive products.
    Type: Grant
    Filed: July 13, 1993
    Date of Patent: April 27, 2004
    Assignee: Unilever Patent Holdings, B.V.
    Inventors: John Oakes, David W Thornthwaite
  • Patent number: 5422028
    Abstract: Cationic peroxyacid are provided having formula (I): ##STR1## wherein: R.sub.1 is an optionally substituted C.sub.1 -C.sub.24 alkyl or alkenyl or alkylaryl with a C.sub.1 -C.sub.24 alkyl group;R.sub.2 and R.sub.3 are each independently a C.sub.1 -C.sub.3 alkyl or C.sub.1 -C.sub.3 substituted alkyl group;R.sub.4 and R.sub.6 are each independently aryl or (CH.sub.2).sub.n where n is an integer from 1 to 7;R.sub.5 is selected from hydrogen, C.sub.1 -C.sub.7 alkyl, or arylsubstituted with a C.sub.1 -C.sub.2 alkyl; andX.sup.- is a counter anion.These cationic peroxyacids show good bleaching activity over a wide range of pH conditions.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: June 6, 1995
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventors: John Oakes, David W. Thornthwaite
  • Patent number: 5360573
    Abstract: Bleaching compositions comprising peroxy acid bleach precursors preferably based on acetylated pentose, hexose or lactose.
    Type: Grant
    Filed: August 5, 1992
    Date of Patent: November 1, 1994
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventors: Richard G. Smith, David W. Thornthwaite
  • Patent number: 5281361
    Abstract: Novel cationic nitriles, methods of preparing such nitriles and use thereof as cationic peroxyacid bleach precursor in bleaching (detergent) compositions are disclosed.The novel cationic nitriles are non-hygroscopic and are characterized in that they have a counter-anion X.sup.- selected from the group consisting of 1) R-SO.sub.3.sup.-, 2) R-SO.sub.4.sup.-, 3) R-CO.sub.2.sup.-, wherein R is a straight or branched chain, optionally substituted, alkyl, alkylether or alkylene group containing 4 to 20 carbon atoms, or a phenyl or alkyl phenyl group containing 6 to 20 carbon atoms, and 4) any other surfactant anion not falling under the groups 1), 2) and 3).
    Type: Grant
    Filed: May 29, 1991
    Date of Patent: January 25, 1994
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventors: Christopher J. Adams, Stephen A. Madison, John Oakes, David W. Thornthwaite
  • Patent number: 5241077
    Abstract: Cationic peroxycarboxylic acids having the general formula (I) ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are each independently a C.sub.1 -C.sub.7 alkyl group or C.sub.1 -C.sub.7 substituted alkyl group, n is an integer of from 2 to 10 and X is a counter anion. The peroxycarboxylic acids may be used in bleaching and detergent compositions.
    Type: Grant
    Filed: March 20, 1992
    Date of Patent: August 31, 1993
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventors: John Oakes, David W. Thornthwaite
  • Patent number: 5236616
    Abstract: Bleaching compositions are disclosed comprising a peroxide bleaching agent and a novel cationic peroxyacid bleach precursor having at least one of the following groups (A) and (B) : ##STR1## wherein R.sub.1 and R.sub.2 are each individually H, or a substituent group containing at least one carbon atom, provided that R.sub.1 and R.sub.2 are not both H.The novel bleach precursor of the cationic nitrile type shows no tendency to deliquesce under normal atmospheric conditions.
    Type: Grant
    Filed: May 24, 1991
    Date of Patent: August 17, 1993
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventors: John Oakes, David W. Thornthwaite
  • Patent number: 5106528
    Abstract: Bleaching and detergent compositions are disclosed which upon dissolution in aqueous medium provide a mixture of hydrophobic and cationic peroxyacids. The compositions which are highly effective at removing a wide range of stain types with better background whiteness at bleach solution temperatures of 40.degree. C. and less, comprise a peroxide bleach compound, a hydrophobic peroxyacid (bleach precursor) and a cationic or amphoteric peroxyacid (bleach precursor).
    Type: Grant
    Filed: May 10, 1990
    Date of Patent: April 21, 1992
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventors: Keith C. Francis, Stephen A. Madison, John Oakes, David W. Thornthwaite
  • Patent number: 5002687
    Abstract: An improved alkaline enzymatic fabric-washing composition is disclosed comprising a surface-active material, detergency builders, an enzyme, a peroxide compound bleach and a peroxyacid bleach precursor of the formula: ##STR1## wherein R is an unsubstituted alkyl group containing 1 to 9 carbon atoms or a phenyl group; and M is hydrogen, alkali metal, alkaline earth metal, ammonium or alkyl or hydroxyalkyl substituted ammonium cation. The composition is effective for washing fabrics at the low temperature region of 40.degree. C. and below.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: March 26, 1991
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventors: David W. Roberts, Peter S. Sims, David W. Thornthwaite
  • Patent number: 4904406
    Abstract: A quaternary ammonium-substituted peroxycarboxylic acid bleach precursor, its quaternary ammonium peroxycarboxylic acid derivative, and bleaching-detergent compositions containing these materials are disclosed herein. The bleach precursor structurally comprises a quaternized ammonium group linked to a carboxyl moiety having a leaving group via an aromatic or heterocyclic bridging group which, upon perhydrolysis in the presence of hydrogen peroxide, generates a highly effective, quaternary ammonium-substituted aromatic or heterocyclic peroxycarboxylic acid bleach.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: February 27, 1990
    Assignee: Lever Brothers Company
    Inventors: James R. Darwent, Keith C. Francis, John Oakes, David W. Thornthwaite
  • Patent number: 4788316
    Abstract: A process for preparing sulphonated aromatic esters of the group consisting of substituted or unsubstituted sulphonato-phenyl carboxylates and sulphonato-phenyl carbonates is disclosed, comprising the steps of:(1) preparing the unsulphonated aromatic ester;(2) sulphonating said unsulphonated aromatic ester; and(3) neutralizing the acid-sulphonated aromatic ester in a non-aqueous organic solvent with an alkali metal, earth alkali metal or ammonium carboxylate in an amount in excess over the amount needed to neutralize the sulphonic acid group(s) and any free or complexed SO.sub.3 present in the product mixture from the sulphonation reaction.Preferred neutralizing agent is sodium acetate; preferred solvents are acetic acid or glyme and diglyme.
    Type: Grant
    Filed: December 16, 1986
    Date of Patent: November 29, 1988
    Assignee: Lever Brothers Company
    Inventors: David W. Thornthwaite, David W. Roberts, Stephen A. Madison
  • Patent number: 4325883
    Abstract: A process for bleaching an oil or fat is disclosed wherein a polar bleaching agent is employed in the presence of a phase transfer catalyst.
    Type: Grant
    Filed: October 24, 1980
    Date of Patent: April 20, 1982
    Assignee: Lever Brothers Company
    Inventors: Keith Jones, Francis R. M. McDonnell, Stuart N. Morgan, David W. Thornthwaite