Patents by Inventor John Robert Lawson

John Robert Lawson 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: 6025114
    Abstract: 1. This invention relates to a liquid composition comprising:a) 2 to 20 parts of a monomeric poly(meth)acrylate having a functionality of at least 3 and a MW of at least 650;b) 20 to 60 parts of a urethane(meth)acrylate having a functionality of 2 to 4 and a MW of 400 to 10,000;c) 20 to 80 parts of a monomeric or oligomeric di(meth)acrylate based on bisphenol A or bisphenol F; andd) 0.1 to 10 parts of a photoinitiator;wherein all parts are by weight and the total number of parts of a)+b)+c)+d) add up to 100.The compositions are suitable for the stereolithographic production of three-dimensional articles such as models of mechanical and body parts and are particularly notable for their low curl & shrinkage coupled with fast rate of cure.
    Type: Grant
    Filed: September 11, 1997
    Date of Patent: February 15, 2000
    Assignee: Zeneca Limited
    Inventors: Ajay Haridas Popat, John Robert Lawson
  • Patent number: 5684101
    Abstract: Process for the free-radical polymerization of at least one olefinically unsaturated monomer, the polymerization being performed in the presence of a compound for effecting molecular weight control, being a CoII chelate of the following formula: ##STR1## wherein each group X is a divalent group which forms with the two carbon atoms to which it is bonded a pericondensed polycyclic group, being a group having 3 or more carbocyclic rings where the oxime-containing carbocyclic ring has carbon atoms in common with 2 or more of the other rings, the polycyclic group being unsubstituted (apart from the oxime groups) or having at least one hydrocarbyl substituent; and wherein each group Q is independently selected from F, Cl, Br, OH, C.sub.1-12 alkoxy, aryloxy, C.sub.
    Type: Grant
    Filed: October 11, 1996
    Date of Patent: November 4, 1997
    Assignee: Zeneca Limited
    Inventors: Andrew Victor Graham Muir, John Robert Lawson, David Mark Haddleton
  • Patent number: 3996221
    Abstract: Dyestuffs of the formula ##STR1## WHEREIN (R).sub.n represents n substituents R each of which may be independently halogen, lower alkyl, lower alkoxy or COOHR.sup.1 is H, optionally substituted lower alkyl, optionally substituted aryl or optionally substituted aralkyl,n is 0-3,(a+b) is 0-4,X is O, S or NR.sup.2, where R.sup.2 is H or optionally substituted lower alkyl,Y is an optionally substituted aliphatic or optionally substituted araliphatic linking group, andEach Z is independently a H or a cellulose-reactive group, and when (a+b) is O there is at least one SO.sub.3 H group as substituent on the groups R.sup.1, X or Y.The dyestuffs when both Z are H are valuable acid dyes, e.g. for wool, and when one or both Z are reactive groups the dyestuffs are valuable reactive dyestuff especially for cellulose fibers.
    Type: Grant
    Filed: January 9, 1975
    Date of Patent: December 7, 1976
    Assignee: Imperial Chemical Industries Limited
    Inventors: John Lindley Leng, Brian Parton, Denis Robert Annesley Ridyard, John Robert Lawson