Patents Represented by Attorney Robert P. O'Flynn
  • Patent number: 5491214
    Abstract: The color of hydrocarbon resins having carbon-carbon double bonds and containing color bodies is lightened by a hydrotreating process comprising contacting a resin having a weight average molecular weight Mw of 250-10,000 with hydrogen in the presence of a catalyst that promotes the hydrogenation of the color bodies without substantially changing the content of carbon-carbon double bonds in the resin. The preferred catalysts are copper chromite and copper/zinc.
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: February 13, 1996
    Assignee: Hercules Incorporated
    Inventors: Norman E. Daughenbaugh, Dane G. Goodfellow
  • Patent number: 5491249
    Abstract: Cyclic polysiloxanes are produced by continuously passing a feed comprising linear polysiloxanes through a reactor containing a solid acidic catalyst at a pressure greater than one atmosphere under an inert atmosphere to produce a mixture comprising volatile cyclic polysiloxanes, nonvolatile reaction products, and unreacted linear polysiloxanes. The volatile products can then be recovered, and the nonvolatile reaction products and unreacted linear polysiloxanes can be added to the linear polysiloxane feed to form a recycle stream that is passed back through the reactor. Recycling increases the yield of the desired cyclic species.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: February 13, 1996
    Assignee: Hercules Incorporated
    Inventor: John N. Kostas
  • Patent number: 5419998
    Abstract: In an aqueous-developable dry-film photoresist containing a carboxyl-group containing film-forming polymeric binder, the improvement wherein the binder is obtained by polymerizing a mixture including: (a) a monomer of the formula H.sub.2 C.dbd.CRCOO[(C.sub.n H.sub.2n)X(C.sub.p H.sub.2p)].sub.m R', wherein R is hydrogen or methyl and R' is a saturated or unsaturated C.sub.5 -C.sub.12 bridged alkyl optionally substituted by at least one C.sub.1 -C.sub.4 alkyl or halogen, X is oxygen or sulfur, n is 2-4, p is 0-4, m is 0-2; and (b) at least one C.sub.3 -C.sub.15 .alpha.,.beta.-unsaturated carboxyl-containing monomer having 3-15 carbon atoms.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: May 30, 1995
    Assignee: Hercules Incorporated
    Inventors: Richard T. Mayes, Rudolph L. Pohl
  • Patent number: 5415972
    Abstract: An aqueous-developable dry-film photopolymerizable composition is disclosed wherein the photopolymerizable composition contains a carboxyl-containing polyurethane having at least one ethylenically unsaturated end group as a plasticizer.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: May 16, 1995
    Assignee: Hercules Incorporated
    Inventor: Richard T. Mayes
  • Patent number: 5242979
    Abstract: This invention is directed to a polymeric composition comprising (a) a continuous phase of a cross-linked organosilicon polymer comprised of alternating (i) polycyclic hydrocarbon residues derived from polycyclic polyenes having at least two non-aromatic, non-conjugated carbon-carbon double bonds in their rings and (ii) residues derived from the group consisting of cyclic polysiloxanes and tetrahedral siloxysilanes, linked through carbon to silicon bonds, and (b) a discontinuous phase of a low molecular weight hydrocarbon elastomer having at least two hydrosilation reactable carbon-carbon double bonds.
    Type: Grant
    Filed: October 5, 1990
    Date of Patent: September 7, 1993
    Assignee: Hercules Incorporated
    Inventors: Paquita E. Barnum, Richard L. Brady