Patents Assigned to SKC Limited
  • Patent number: 7144973
    Abstract: The biaxially oriented, white polyester film of the present invention having improved flame-retardancy, covering ability, flexibility and heat-resistance comprises a polyester resin having an intrinsic viscosity of 0.4 to 0.9 dl/g, a flame-retardant which is alkylene bistetrabromophthalimide or decabromodiphenylalkane, and a fluorescent whitening agent, said polyester film being biaxially drawn at a total draw ratio of 9 or more.
    Type: Grant
    Filed: October 19, 2004
    Date of Patent: December 5, 2006
    Assignee: SKC Limited
    Inventors: Jae-Suk Joo, Gwan-Hyung Lee, Yong-Won Kim
  • Patent number: 7018689
    Abstract: A heat-shrinkable polyester film comprising a polyester base film and a coat layer formed on one or both sides of the polyester base film, said coat layer comprising a copolymerised polyester having carboxyl group terminals and Tg in the range of 70 to 80;É, exhibits superior properties suitable for labeling or shrink-wrapping containers.
    Type: Grant
    Filed: November 2, 2002
    Date of Patent: March 28, 2006
    Assignee: SKC Limited
    Inventors: Junggyu Lee, Jonghyuk Eun, Namil Kim, Sangil Kim, Yongin Park, Changju Lee
  • Patent number: 6902819
    Abstract: The biaxially oriented polyester film of the present invention useful for twist wrapping is prepared by biaxially drawing a polyester sheet which has a glass transition temperature (Tg) of at least 60° C., in the longitudinal and transverse directions, wherein the biaxially oriented film has a specific gravity of 1.38 or less.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: June 7, 2005
    Assignee: SKC Limited
    Inventors: Sangil Kim, Changju Lee
  • Patent number: 6818312
    Abstract: Disclosed in this invention is a heat-shrinkable polyester film comprising a polyester film support and a coat layer formed on one or both sides of the polyester film support, said coat layer comprising a quaternary ammonium sulfate and a polysiloxane resin.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: November 16, 2004
    Assignee: SKC Limited
    Inventors: Jung-Gyu Lee, Nam-Il Kim, Sang-Il Kim
  • Patent number: 6794088
    Abstract: The lithium ion polymer battery having high capacity, capacity retention and cycling life is prepared by gelating a gel polymer electrolyte composition comprising an organic solvent, a lithium salt, and a gelling agent composed of a nitrogen-containing polymer and an epoxy group-containing polymer at room temperature according to the present invention free from heating step at a low cost.
    Type: Grant
    Filed: March 11, 2003
    Date of Patent: September 21, 2004
    Assignee: SKC Limited
    Inventors: Kwon-Sun Roh, Jae-Myoung Lee, Jon-Ha Lee
  • Patent number: 6410134
    Abstract: A silicone coating composition comprising an alkylvinylpolysiloxane, an alkylhydrogenpolysiloxane, a platinum complex catalyst and a water-soluble polyester resin is advantageously used for the preparation of a polyester release film having good release property and improved rub-off resistance.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: June 25, 2002
    Assignee: SKC Limited
    Inventors: Eung-Sik Park, Jong-Seob Won
  • Patent number: 6355326
    Abstract: A phase change optical disk having excellent corrosion resistance, recording signal properties and overwrite cyclability, which contains a first dielectric layer, a recording layer, a second dielectric layer, a reflection layer and a protection layer, characterized in that the reflection layer comprises a first reflection layer made of a metal or an alloy thereof having an electronegativity ranging from 1.9 to 3.0 and a second reflection layer made of Cu, Ag or an alloy thereof, said first reflection layer being in closed contact with the second dielectric layer, and the second reflection layer, with the first reflection layer and the protection layer.
    Type: Grant
    Filed: September 28, 1999
    Date of Patent: March 12, 2002
    Assignee: SKC Limited
    Inventors: Jae-Won Lee, Jung-Ki Jun
  • Patent number: 6063469
    Abstract: A triple substrate optical disk comprises a center substrate layer, a top substrate layer, a bottom substrate layer, a top adhesion layer bonding the top substrate layer to the center substrate layer and a bottom adhesion layer bonding the center substrate layer to the bottom substrate layer. The center substrate layer has a center substrate containing a top surface and a bottom surface thereof, a first recording layer deposited on the top surface of the center substrate and a second recording layer deposited on the bottom surface of the center substrate. The top substrate layer includes a top substrate and a third recording layer, wherein the top substrate has a top surface and a bottom surface thereof and the third recording layer is deposited on the bottom surface of the top substrate.
    Type: Grant
    Filed: October 22, 1998
    Date of Patent: May 16, 2000
    Assignee: SKC Limited
    Inventors: Su-Sun Ryu, Chang-Yong Lee
  • Patent number: 5897959
    Abstract: A biaxially extended polyester film which comprises a polyester resin having ethylene A biaxially oriented polyester film comprises a polyester resin having ethylene terephthalate and ethylene isophthalate repeating units in a weight ratio of 90:10 to 75:25; 0.02 to 0.06 weight % of an organic phosphite or phosphate ester; and 0.01 to 0.05 weight % of a hindered phenol compound, wherein the film possesses good thermal stability, processability, and thermal adhesive strength to a metal surface and is useful in forming the inner laminate layer of a metal container.
    Type: Grant
    Filed: November 20, 1996
    Date of Patent: April 27, 1999
    Assignee: SKC Limited
    Inventors: Sang-Il Kim, Byoung-Ho Cho
  • Patent number: 5864005
    Abstract: A copolyester resin having excellent physical properties and a low acetaldehyde content is produced by: polycondensing a mixture of terephthalic acid and isophthalic acid with a glycol in the presence of a phosphate compound to prepare a copolyester prepolymer having an intrinsic viscosity of more than 0.5 dl/g; subjecting the copolyester prepolymer to a first heat-treatment to obtain a pre-crystallized resin; and subjecting the pre-crystallized resin to a second heat-treatment, to obtain a copolyester resin having an intrinsic viscosity of 0.62 to 0.80 dl/g and a melting point of 190.degree. to 240.degree. C.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: January 26, 1999
    Assignee: SKC, Limited
    Inventors: Sang-Il Kim, Bum-Sang Kim
  • Patent number: 5858527
    Abstract: A biaxially oriented polyester film consisting essentially of a polyester resin, polytetrafluoroethylene resin particles having an average particle diameter of 3 to 8 .mu.m in an amount ranging from 0.3 to 0.6% by weight based on the weight of the polyester resin, and a polyacrylate dispersant in the amount 0.05 to 5 wt % based on the weight of polytetrafluoroethylene particles. The film possesses excellent surface properties, e.g., abrasion resistance, scratch resistance, transparency, void resistance, surface smoothness, slurry stability, running property and dielectric strength.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: January 12, 1999
    Assignee: SKC Limited
    Inventors: Kwang-Hyung Lee, Seung-Soo Woo
  • Patent number: 5838444
    Abstract: A magneto-optic characteristic measuring device which is adapted to measure a Kerr rotation angle is a kind of magneto-optic characteristic exhibited in materials used for magneto-optic recording media. Known materials exhibiting a magnetic Kerr effect have very small Kerr rotation angle ranging from about 0.1.degree. to about 0.5.degree.. As a result, it is difficult to accurately measure such a small Kerr rotation angle using known measuring devices due to an influence caused by noise components. In the magneto-optic characteristic measuring apparatus, its electronic circuit unit, which serves to magneto-optically modulate a laser beam from an optical unit introduced in a beam splitter via a polarizer and to record the modulated beam in an X-Y recorder using a detect signal from an optical detector unit, includes a lock-in amplifier,.thereby accurately measuring a small Kerr rotation angle.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: November 17, 1998
    Assignee: SKC Limited
    Inventor: Yung Kuk Jo
  • Patent number: 5756032
    Abstract: A biaxially extended polyester film comprising light calcium carbonate particles, spherical silica particles and .gamma.- or .delta.-alumina particles or a mixture thereof treated with a silane coupling agent prepared by the inventive process possesses excellent surface and physical properties.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: May 26, 1998
    Assignee: SKC Limited
    Inventors: Kwang-Hyung Lee, Seung-Soo Woo
  • Patent number: 5718860
    Abstract: A polyester base film for magnetic recording media having improved adhesion to the magnetic layer applied thereon as well as good abrasion and scratch resistance prepared by melt-extruding a polyester resin containing inorganic and organic particles to form a sheet; extending the sheet; and heat-setting the extended film, wherein the heat-setting step is carried out by heat-treating a first surface of the film, which is to be coated with a magnetic material, at a temperature ranging from 170.degree. to 290.degree. C. for 1 to 50 seconds so that the crystallinity thereof ranges from 50 to 70% and heat-treating the other surface of the film at a temperatue which is lower than the first heat-treatment temperature by 20.degree. C. or more for 1 to 200 seconds so that the other surface attains a crystallinity which is lower than that of the first surface by at least 5%.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: February 17, 1998
    Assignee: SKC Limited
    Inventors: Jae-Woong Lee, Joon-Hee Han
  • Patent number: 5718971
    Abstract: A biaxially oriented polyester film comprises: 0.01 to 4 wt % of .gamma., .delta.- .theta.-alumina or a mixture thereof having an average particle diameter ranging from 0.005 to 3 .mu.m and a Mohs hardness of 6 or more; 0.05 to 5 wt %, based on the amount of the alumina employed, of a silane coupling agent of the following formula (I); and, optionally, 0.01 to 4 wt % of spherical silica particle having an average particle diameter ranging from 0.005 to 3 .mu.m:R.sub.1 --R.sub.2 --Si--(OR.sub.3).sub.3 (I)wherein,R.sub.1 is a methacryl, an acryl, a glycidyl or an amino group;R.sub.2 is a C.sub.1-5 alkylene group; andR.sub.3 is a C.sub.1-3 alkyl group.The film has improved transparency as well as surface properties, and is especially useful as labels, window coating films, photoresists and the like.
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: February 17, 1998
    Assignee: SKC Limited
    Inventors: Kwang-Hyung Lee, Gwan-Hyung Lee, Young-Jin Lee
  • Patent number: 5714553
    Abstract: Apparatus for preparing a polyester resin by polymerizing a monomer produced by transesterifying a dicarboxylic acid component with a diol component while removing the vapor containing diols and other low molecular weight compound released during the polymerization, which comprises:a polymerization reactor;a condenser having an inlet, a heat exchanger and an outlet, the inlet being located below the heat exchanger and connected to the polymerization reactor while the outlet being positioned above the heat exchanger;a baffle installed between the inlet and the heat exchanger of the condenser such that the flow of the vapor is directed toward the bottom of the condenser;a trap located below the condenser to collect the condensate of the vapor; anda vacuum pump connected to the outlet of the condenser.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: February 3, 1998
    Assignee: SKC Limited
    Inventors: Nam-Il Kim, Seong-Ill Cheong, Young-Jin Lee
  • Patent number: 5699848
    Abstract: A method for forming a replica stamper for use in mass producing an optical disk, wherein the optical disk has a plurality of tracks arranged spirally or concentrically, and each of the tracks includes a recess and a protrusion for recording information signals thereon, comprises the steps of: (a) preparing a master stamper having a top surface and a flat bottom surface, wherein the top surface of the master stamper includes a plurality of tracks corresponding to the plurality of tracks of the optical disk; (b) depositing a buffer layer on the top surface of the master stamper; (c) forming a replica stamper on top of the buffer layer; (d) disengaging the master stamper from the buffer layer and the replica stamper; and (e) removing the buffer layer from the replica stamper.
    Type: Grant
    Filed: November 20, 1995
    Date of Patent: December 23, 1997
    Assignee: SKC Limited
    Inventors: Chang-Yong Lee, Joo-Hwan Kim, Soo-Sun Ryu
  • Patent number: 5676902
    Abstract: A process for preparing a thermoplastic resin film having uniform physical and chemical properties includes extending a thermoplastic resin sheet in a longitudinal direction so that the crystallization energy of the longitudinally extended sheet is 20 J/g or more to give a longitudinally extended sheet, extending the longitudinally extended sheet in a transverse direction to give a biaxially extended film, and heat treating the biaxially extended film to give the resin film.
    Type: Grant
    Filed: July 5, 1995
    Date of Patent: October 14, 1997
    Assignee: SKC Limited
    Inventors: Jeong-Wook Seo, Wan-Sup Shim, Young-Jin Lee
  • Patent number: D411840
    Type: Grant
    Filed: May 7, 1997
    Date of Patent: July 6, 1999
    Assignee: SKC Limited
    Inventor: Bong Young Lee
  • Patent number: D411993
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: July 13, 1999
    Assignee: SKC Limited
    Inventor: Bong Young Lee