Patents by Inventor Chander P. Chawla

Chander P. Chawla 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).

  • Publication number: 20020082323
    Abstract: The present invention provides radiation-curable compositions for coating plastic substrates, wherein the compositions, after cure, have a combination of sufficient adhesion, flexibility, and hardness.
    Type: Application
    Filed: September 14, 2001
    Publication date: June 27, 2002
    Inventors: Chander P. Chawla, Christopher Tronche
  • Publication number: 20020064357
    Abstract: Optical fiber coatings are disclosed having excellent ribbon stripping and adhesion behavior. The coatings are radiation-curable. The excellent stripping and adhesion behavior can be achieved by several means which include by use of additives, by use of radiation-curable oligomers having higher molecular weight, or by use of coatings having certain thermal properties. Combination of means can be employed. Stripping behavior can be measured by crack propagation and fiber friction measurements.
    Type: Application
    Filed: January 11, 2001
    Publication date: May 30, 2002
    Applicant: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, James R. Petisce, John T. Vandeberg, George Pasternack, Timothy E. Bishop, Paul E. Snowwhite, Edward P. Zahora, Stephen C. Lapin
  • Patent number: 6379866
    Abstract: This invention discloses compositions adapted to produce, through solid imaging means, excellent quality objects having material properties that simulate the look and feel of polypropylene articles.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: April 30, 2002
    Assignee: DSM Desotech Inc
    Inventors: John A. Lawton, Chander P. Chawla
  • Patent number: 6376571
    Abstract: A fast curing radiation-curable composition useful as coating compositions for inner and outer primary coatings, inks, ribbons other matrix material coating layers for coating and surrounding optical fibers. The improved radiation-curable compositions, having a propoxylated monomer or oligomer component, demonstrate unexpectedly fast cure speeds while providing strong adhesion characteristics to a variety of substrates and can also be used as a general radiation-curable adhesive or can be adapted for use in the specialized process of digital versatile disk (DVD) production.
    Type: Grant
    Filed: March 6, 1998
    Date of Patent: April 23, 2002
    Assignee: DSM N.V.
    Inventors: Chander P. Chawla, Gerry K. Noren
  • Publication number: 20020037146
    Abstract: Optical fiber coatings are disclosed having excellent ribbon stripping and adhesion behavior. The coatings are radiation-curable. The excellent stripping and adhesion behavior can be achieved by several means which include by use of additives, by use of radiation-curable oligomers having higher molecular weight, or by use of coatings having certain thermal properties. Combination of means can be employed. Stripping behavior can be measured by crack propagation and fiber friction measurements.
    Type: Application
    Filed: January 11, 2001
    Publication date: March 28, 2002
    Applicant: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, James R. Petisce, John T. Vandeberg, George Pasternack, Timothy E. Bishop, Paul E. Snowwhite, Edward P. Zahora, Stephen C. Lapin
  • Patent number: 6362249
    Abstract: A radiation-curable, optical fiber coating composition has enhanced color stabilization and is formulated from a composition containing at least one radiation-curable oligomer or monomer. A concentration of urethane and ether linkages in the radiation-curable composition is such that a cured optical fiber coating formed from said radiation-curable composition exhibits a &Dgr;E of about 40 or less after being exposed for 96 hours to 150° C. and then for 144 hours to 180° C. Also provided is a radiation-curable optical fiber coating composition which is substantially urethane-free.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: March 26, 2002
    Assignee: DSM Desotech Inc.
    Inventor: Chander P. Chawla
  • Publication number: 20020013383
    Abstract: A method of making radiation-curable, fiber optic materials having extended shelf-life and reduced water content which when suitably cured provide reliable and consistent adhesion characteristics to optical glass fibers.
    Type: Application
    Filed: January 29, 2001
    Publication date: January 31, 2002
    Inventors: Chander P. Chawla, Steven R. Schmid, John M. Zimmerman, James M. Julian
  • Patent number: 6339666
    Abstract: Optical fiber coatings are disclosed having excellent ribbon stripping and adhesion behavior. The coatings are radiation-curable. The excellent stripping and adhesion behavior can be achieved by several means which include by use of additives, by use of radiation-curable oligomers having higher molecular weight, or by use of coatings having certain thermal properties. Combination of means can be employed. Stripping behavior can be measured by crack propagation and fiber friction measurements.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: January 15, 2002
    Assignee: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, James R. Petisce, John T. Vandeberg, George Pasternack, Timothy E. Bishop, Paul E. Snowwhite, Edward P. Zahora, Stephen C. Lapin
  • Publication number: 20010033725
    Abstract: Optical fiber coatings are disclosed having excellent ribbon stripping and adhesion behavior. The coatings are radiation-curable. The excellent stripping and adhesion behavior can be achieved by several means which include by use of additives, by use of radiation-curable oligomers having higher molecular weight, or by use of coatings having certain thermal properties. Combination of means can be employed. Stripping behavior can be measured by crack propagation and fiber friction measurements.
    Type: Application
    Filed: April 20, 2001
    Publication date: October 25, 2001
    Inventors: David M. Szum, Chander P. Chawla, James R. Petisce, John T. Vandeberg, George Pasternack, Timothy E. Bishop, Paul E. Snowwhite, Edward P. Zahora, Stephen C. Lapin
  • Patent number: 6298189
    Abstract: Optical fiber coatings are disclosed having excellent ribbon stripping and adhesion behavior. The coatings are radiation-curable. The excellent stripping and adhesion behavior can be achieved by several means which include by use of additives, by use of radiation-curable oligomers having higher molecular weight, or by use of coatings having certain thermal properties. Combination of means can be employed. Stripping behavior can be measured by crack propagation and fiber friction measurements.
    Type: Grant
    Filed: March 6, 1998
    Date of Patent: October 2, 2001
    Assignee: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, James R. Petisce, John T. Vandeberg, George Pasternack, Timothy E. Bishop, Paul E. Snowwhite, Edward P. Zahora, Stephen C. Lapin
  • Publication number: 20010025062
    Abstract: Radiation-curable inner and outer primary optical fiber coatings are disclosed having both fast cure speed and reduced rates of yellowing. The compositions comprise particular photoinitiators and UV absorbers which are used in amounts to provide the combination of properties. The UV absorber can have ethylenic unsaturation. Outer primary coatings can be formulated to screen inner primary coatings and have fast cure speed.
    Type: Application
    Filed: December 22, 2000
    Publication date: September 27, 2001
    Applicant: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, Timothy E. Bishop
  • Publication number: 20010008906
    Abstract: A radiation-curable, optical fiber coating composition has enhanced color stabilization and is formulated from a composition containing at least one radiation-curable oligomer or monomer. A concentration of urethane and ether linkages in the radiation-curable composition is such that a cured optical fiber coating formed from said radiation-curable composition exhibits a &Dgr;E of about 40 or less after being exposed for 96 hours to 150° C. and then for 144 hours to 180° C. Also provided is a radiation-curable optical fiber coating composition which is substantially urethane-free.
    Type: Application
    Filed: September 4, 1998
    Publication date: July 19, 2001
    Inventor: CHANDER P. CHAWLA
  • Patent number: 6214899
    Abstract: A method of making radiation-curable, fiber optic materials having extended shelf-life and reduced water content which when suitably cured provide reliable and consistent adhesion characteristics to optical glass fibers.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: April 10, 2001
    Assignee: DSM N.V.
    Inventors: Chander P. Chawla, Steven R. Schmid, John M. Zimmerman, James M. Julian
  • Patent number: 6187835
    Abstract: Radiation-curable inner and outer primary optical fiber coatings are disclosed having both fast cure speed and reduced rates of yellowing. The compositions comprise particular photoinitiators and UV absorbers which are used in amounts to provide the combination of properties. The UV absorber can have ethylenic unsaturation. Outer primary coatings can be formulated to screen inner primary coatings and have fast cure speed.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: February 13, 2001
    Assignee: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, Timothy E. Bishop
  • Patent number: 6169126
    Abstract: Optical fiber primary coating systems are disclosed having excellent ribbon stripping and adhesion behavior. The coatings are radiation-curable. The excellent stripping and adhesion behavior can be inner primary coating composition having a slip enhancing component and a high modulus outer primary coating composition. Combination of means can be employed. Stripping behavior can be measured by crack propagation and fiber friction measurements.
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: January 2, 2001
    Assignee: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, James R. Petisce, George Pasternack, Timothy E. Bishop, Paul E. Snowwhite, Edward P. Zahora
  • Patent number: 6110593
    Abstract: Optical fiber primary coating systems are disclosed having excellent ribbon stripping and adhesion behavior. The coatings are radiation-curable. The excellent stripping and adhesion behavior can be inner piramry coating composition having a slip enhancing component and a high modulus outer primary coating composition. Combination of means can be employed. Stripping behavior can be measured by crack propagation and fiber friction measurements.
    Type: Grant
    Filed: May 21, 1998
    Date of Patent: August 29, 2000
    Assignee: DSM N.V.
    Inventors: David M. Szum, Chander P. Chawla, James R. Petisce, George Pasternack, Timothy E. Bishop, Paul E. Snowwhite, Edward P. Zahora
  • Patent number: 6052503
    Abstract: Provided is an optical glass fiber assembly containing a matrix material and a plurality of coated optical glass fibers bound together by said matrix material, said matrix material having a swell index and/or glass transition temperature which provides the combination of properties of: (i) a swell index of a magnitude functionally capable of facilitating mid-span access to said optical glass fibers by a solvent stripping method of said matrix material from said optical glass fibers; and/or (ii) a glass transition temperature of a magnitude to facilitate end-access to said optical glass fibers by a heat stripping method of said matrix material from said optical glass fibers at an end terminus of said optical glass fiber assembly.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: April 18, 2000
    Assignee: DSM N.V.
    Inventors: James J. Schouten, David M. Szum, Chander P. Chawla
  • Patent number: 5977202
    Abstract: A radiation-curable composition for use as an optical fiber material or coating comprising the combination of the following pre-mixture ingredients:(A) about 5 wt. % to about 95 wt. % of one or more radiation-curable oligomers,(B) about 5 wt. % to about 95 wt. % of one or more monomer diluents,(C) optionally, one or more photoinitiators,(D) about 0.1 wt. % to about 30 wt. % of one or more adhesion promoters represented by:(R.sup.1 --L).sub.4-X --Si(OR.sup.2).sub.Xwherein R.sup.1 is a group comprising an ethylenically unsaturated radiation-curable group; and said three R.sup.2 groups independently of each other are C.sub.1 -C.sub.10 groups; wherein X=1-3; and L is a linking group which comprises one or more alkoxy or branched propoxy groups.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: November 2, 1999
    Assignee: DSM N.V.
    Inventors: Chander P. Chawla, Paul E. Snowwhite, Edward P. Zahora
  • Patent number: 5907023
    Abstract: The invention provides a radiation-curable coating composition comprising:(A) 30-90% by weight of a urethane oligomer having three types of moieties: (I) a polyether/polyolefin block copolymeric backbone, (II) an aromatic group having one or more alkyl substituents, and (III) reactive termini, the three types of moieties being connected via urethane and/or urea linkages, the aromatic group being connected to a urethane and/or urea linkage via the one or more alkyl substituents;(B) 5-65% by weight of one or more reactive diluents, each diluent being terminated with at least one end group capable of reacting with the reactive terminus of (A);(C) optionally, 0-10% by weight of at least one photoinitiator;(D) optionally, 0-5% by weight antioxidant; and(E) 0-30% by weight adhesion promoter.The compositions have an excellent combination of properties including good optical clarity, good resistance to moisture and hexane, and high refractive index.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: May 25, 1999
    Assignee: DSM NV
    Inventor: Chander P. Chawla
  • Patent number: 5696179
    Abstract: The invention provides a silane-oligomer (A) of the following formula:(R.sup.3)--X--(R.sup.1.sub.x)--Y--Si(R.sup.2).sub.3 ( 1)wherein R.sup.3 is a group having a functionality that can be polymerized through actinic radiation, R.sup.1.sub.x is a backbone-oligomer having a molecular weight of more than about 200, R.sup.2 is a hydrolyzable group, and X and Y are coupling groups. The invention also provides a glass coating composition containing the silane-oligomer.
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: December 9, 1997
    Assignee: DSM, N.V.
    Inventor: Chander P. Chawla