Patents by Inventor Ligia Dominguez

Ligia Dominguez 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: 6793083
    Abstract: A preblended additive composition and process for the preparation of polyester resins useful in the manufacture of plastic containers such as bottles is disclosed. The additive composition includes a cobalt-containing compound that is preblended with a phosphorous compound. The polyester resin, e.g., a PET resin, may be prepared by reacting ethylene glycol with dimethyl terephthalate (DMT) or terephthalic acid (TA) in an esterification reaction. The additive composition may be prepared by quickly dumping the phosphorus compound into the cobalt compound such as cobalt acetate, and the resulting composition is added to the reactor vessel before the polycondensation reaction. On the other hand, the additive composition may be prepared by slowly dumping the phosphorus compound into the cobalt compound over a period of at least 5 minutes. Such preblending substantially eliminates any yellow or blue color, or haze in the product article.
    Type: Grant
    Filed: September 2, 2003
    Date of Patent: September 21, 2004
    Assignee: Invista North America S.A.R.L.
    Inventors: Rehka V. Kulkarni, Ligia Dominguez
  • Patent number: 6787630
    Abstract: Process for the preparation of heat-stable, antimony-free polyesters of neutral color and the products which can be prepared by this process A process for the preparation of heat-stable, antimony-free polyesters of neutral color by esterification of aromatic dicarboxylic acids or transesterification of lower aliphatic esters of aromatic dicarboxylic acids with aliphatic diols and subsequent polycondensation in which a possible transesterification is carried out in the presence of 20 to 120 ppm, based on the catalyst metal, of a transesterification catalyst, after the esterification or transesterification has ended, phosphoric acid, phosphorous acid and/or phosphonic acids or a derivative thereof are added to the esterification or transesterification batch as a completing agent in an amount which is 100% of the amount equivalent to the transesterification catalyst employed and up to 99% of the amount equivalent to the cobalt to be employed, up to 80 ppm of cobalt in the form of a cobalt compound are then adde
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: September 7, 2004
    Assignee: Arteva North America S.A.R.L.
    Inventors: Ligia Dominguez De Walter, Banks Bryan Moore, Peter Klein
  • Publication number: 20040044172
    Abstract: A preblended additive composition and process for the preparation of polyester resins useful in the manufacture of plastic containers such as bottles is disclosed. The additive composition includes a cobalt-containing compound that is preblended with a phosphorous compound. The polyester resin, e.g., a PET resin, may be prepared by reacting ethylene glycol with dimethyl terephthalate (DMT) or terephthalic acid (TA) in an esterification reaction. The additive composition may be prepared by quickly dumping the phosphorus compound into the cobalt compound such as cobalt acetate, and the resulting composition is added to the reactor vessel before the polycondensation reaction. On the other hand, the additive composition may be prepared by slowly dumping the phosphorus compound into the cobalt compound over a period of at least 5 minutes. Such preblending substantially eliminates any yellow or blue color, or haze in the product article.
    Type: Application
    Filed: September 2, 2003
    Publication date: March 4, 2004
    Applicant: ARTEVA NORTH AMERICA S.a.r.l.
    Inventors: Rekha V. Kulkarni, Ligia Dominguez
  • Patent number: 6632917
    Abstract: A preblended additive composition and process for the preparation of polyester resins useful in the manufacture of plastic containers such as bottles is disclosed. The additive composition includes a cobalt-containing compound that is preblended with a phosphorous compound. The polyester resin, e.g., a PET resin, may be prepared by reacting ethylene glycol with dimethyl terephthalate (DMT) or terephthalic acid (TA) in an esterification reaction. The additive composition may be prepared by quickly dumping the phosphorus compound into the cobalt compound such as cobalt acetate, and the resulting composition is added to the reactor vessel before the polycondensation reaction. On the other hand, the additive composition may be prepared by slowly dumping the phosphorus compound into the cobalt compound over a period of at least 5 minutes. Such preblending substantially eliminates any yellow or blue color, or haze in the product article.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: October 14, 2003
    Assignee: Arteva North America S.A.R.L.
    Inventors: Rehka V. Kulkarni, Ligia Dominguez
  • Patent number: 5874517
    Abstract: There is disclosed a process for reducing the amount of acetaldehyde generated when polyethylene terephthalate (PET) chip is subjected to high temperatures in order to render the PET chip suitable for making food containers, particularly beverage bottles. This process comprises the addition of primary and secondary antioxidants either prior to or after the PET polycondensation reaction in order to reduce the amount of regenerated acetaldehyde produced by the polymer. The polyethylene terephthalate produced by this process reduces regenerated acetaldehyde by at least 25% in comparison to control resin produced without antioxidants, while maintaining suitable color for use as clear glass replacement. There is also disclosed a process for molding a PET preform wherein the polymer prepared as described above is melted, formed into the desired preform shape, and solidified by cooling. This preform can then be reheated above its glass transition temperature and molded into the desired container shape.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: February 23, 1999
    Assignee: Hoechst Celanese Corporation
    Inventors: Xiaoyan Huang, Ligia Dominguez
  • Patent number: 5874515
    Abstract: There is disclosed a process for reducing the number of gels generated in polyethylene terephthalate (PET) resin. Gels are crosslinked polymers created by thermal and thermo-oxidative degradation induced during polymer production. The instant process comprises the addition of primary and secondary antioxidants prior to the PET polycondensation reaction in order to reduce the amount of thermal degradation which occurs. The polyethylene terephthalate produced by this process formed approximately 25 to 90% fewer gels while maintaining physical properties suitable for use in fiber, film, and molding applications.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: February 23, 1999
    Assignee: Hoechst Celanese Corporation
    Inventors: Xiaoyan Huang, Ligia Dominguez
  • Patent number: 5283316
    Abstract: The present invention provides a process for the production of polymers with an optical position in diagram where refraction index n.sub.D is plotted against optical dispension v.sub.D expedient for an optical use by metathetic counterion exchange, wherein, in a polymer of the general formula: ##STR1## R.sub.1 and R.sub.2, which can be the same or different, are divalent organic radicals, R.sub.3 and R.sub.4, which can be the same or different, are monovalent organic radicals, n is a whole number greater than 2 and y is 0 or 1. R.sub.1, R.sub.2, R.sub.3, R.sub.4, y and n are so chosen that together they form a polymeric basic structure which promotes glass formation and prevents crystallisation, and X.sup.- is a halogen atom. The halogen ion is replaced by an equivalent of a mono- or polyvalent organic or inorganic counterion different from the halogen ion and suitable for the adjustment of the desired solid body properties.
    Type: Grant
    Filed: June 4, 1992
    Date of Patent: February 1, 1994
    Assignee: Max-Planck-Gesellschaft Zur Fordrung Der Wissenchaften
    Inventors: Ligia Dominguez, Wolfgang H. Meyer, Ullrich Simmrock, Gerhard Wagner