Patents by Inventor Chah M. Shen

Chah M. Shen 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: 4405773
    Abstract: Hydrophilic contact lenses produced by polymerizing(a) hydroxyalkyl monoesters of acrylic or methacrylic acid,(b) monomers having the formula ##STR1## where R, is hydrogen or methyl, R.sub.2 is alkylene, R.sub.3 is alkoxy and n is 1 or 2, and(c) acrylic acid or methacrylic acid.Methods of producing the lenses are disclosed.
    Type: Grant
    Filed: February 5, 1982
    Date of Patent: September 20, 1983
    Assignee: Schering Corporation
    Inventors: Samuel Loshaek, Chah M. Shen
  • Patent number: 4312725
    Abstract: This invention relates to contact lenses having an oxygen gas permeability constant of at least ##EQU1## comprising homopolymers and interpolymers formed by the polymerization of monomers comprising at least one alkyl styrene monomer having at least one C.sub.1 or higher alkyl group on the aromatic ring and improved surface wettability and to the method of making such contact lenses utilizing ultraviolet (UV) and chemical treatment.
    Type: Grant
    Filed: January 31, 1980
    Date of Patent: January 26, 1982
    Assignee: Wesley-Jessen, Inc.
    Inventors: Samuel Loshaek, Chah M. Shen
  • Patent number: 4228269
    Abstract: This invention relates to bonnets for making contact lenses and contact lenses having high gas permeability shaped from a polymer selected from (a) polymers consisting essentially of the polymerization reaction products of one or a combination of different alkyl styrene monomers with one or more alkyl substituents on the aromatic ring and an unsubstituted vinyl group, and optionally at least one compatible cross-linking monomer, (b) polymers consisting essentially of the polymerization reaction products of at least one alkyl styrene monomer as defined in (a) with one or a combination of other styrene monomers selected from styrene, styrene with an alkyl substituent on the vinyl group only, and styrene with both an alkyl substituent on the vinyl group and one or more alkyl substituents on the aromatic ring, and optionally at least one compatible cross-linking monomer and (c) polymers consisting essentially of the polymerization reaction products of one of the styrenes defined in (a) and (b) or combinations the
    Type: Grant
    Filed: June 8, 1978
    Date of Patent: October 14, 1980
    Assignee: Wesley-Jessen Inc.
    Inventors: Samuel Loshaek, Chah M. Shen
  • Patent number: 4182802
    Abstract: Cross-linked hydrophilic interpolymers and contact lenses made therefrom comprising hydrophilic units of which the only or major proportion are derived from an N-vinyl heterocyclic monomer, hydrophobic units derived from the group consisting of styrene and ring-substituted styrenes, and cross-linking units derived from monomers containing two or more polymerizable double bonds per monomer unit.
    Type: Grant
    Filed: December 27, 1977
    Date of Patent: January 8, 1980
    Inventors: Samuel Loshaek, Chah M. Shen
  • Patent number: 4111535
    Abstract: This invention comprises a gas-permeable contact lens consisting essentially of a plasticized cellulose resin selected from a partially esterified or partially etherified cellulose polymer plasticized with a compatible plasticizer in an amount sufficient to increase the gas permeability of the cellulose resin.
    Type: Grant
    Filed: October 12, 1976
    Date of Patent: September 5, 1978
    Assignee: Wesley-Jessen Inc.
    Inventors: Samuel Loshaek, Chah M. Shen
  • Patent number: 4109070
    Abstract: In the process of making optically clear hydrophilic copolymers formed by copolymerizing a glycol monoester of acrylic or methacrylic acid with an alkoxy monomer having the formula: ##STR1## wherein R is a C.sub.1 -C.sub.4 straight or branched chain alkoxy group, R' is a C.sub.2 or C.sub.3 straight or branched chain alkylene group, X is hydrogen or a methyl group, m is either 1 or 0, and n is an integer from 1 to 20, the improvement comprising distilling at least said alkoxy monomer under high vacuum and low temperature prior to copolymerization, promptly adding to said distilled monomer an amount of polymerization inhibitor below that which would inhibit copolymerization, but sufficient to provide a hydrated copolymer of high optical clarity, and then copolymerizing said monomer and said glycol monoester to form said hydrophilic copolymer. The invention also comprises the improved method of making hydrophilic buttons and contact lenses, particularly corneal contact lenses, from said hydrophilic copolymers.
    Type: Grant
    Filed: June 7, 1977
    Date of Patent: August 22, 1978
    Assignee: Wesley-Jessen Inc.
    Inventors: Samuel Loshaek, Chah M. Shen
  • Patent number: RE30368
    Abstract: This invention comprises a gas-permeable contact lens consisting essentially of a plasticized cellulose resin selected from a partially esterified or partially etherified cellulose polymer plasticized with a compatible plasticizer in an amount sufficient to increase the gas permeability of the cellulose resin.
    Type: Grant
    Filed: March 5, 1979
    Date of Patent: August 12, 1980
    Assignee: Wesley-Jessen Inc.
    Inventors: Samuel Loshaek, Chah M. Shen
  • Patent number: RE31422
    Abstract: Cross-linked hydrophilic interpolymers and contact lenses made therefrom comprising hydrophilic units of which the only or major proportion are derived from .Iadd.vinyl pyridine or .Iaddend.an N-vinyl heterocyclic monomer, hydrophobic units derived from the group consisting of styrene and ring-substituted styrenes, and cross-linking units derived from monmers containing two or more polymerizable double bonds per monomer unit.
    Type: Grant
    Filed: December 9, 1981
    Date of Patent: October 18, 1983
    Assignee: Schering Corporation
    Inventors: Samuel Loshaek, Chah M. Shen