Patents Assigned to TDK Electronics Co. Ltd.
  • Patent number: 4416947
    Abstract: A magnetic recording medium is provided which has smooth and stable running performances and is free of "squeal" phenomenon, especially in an environment of high temperature and high humidity. A highly viscous silicone oil having a viscosity of 100,000 centistokes or more is incorporated in combination with a higher fatty acid ester composed of a higher fatty having a melting point of 44.degree. C. or more and a monohydric alcohol containing 3 to 8 carbon atoms into a magnetic coating layer of the magnetic recording medium. Such silicone oil is represented by the general formula: ##STR1## wherein R is CH.sub.3, R' is CH.sub.3, C.sub.6 H.sub.5 or F and n is a number which determines a viscosity thereof. Such higher fatty acid ester is selected from butyl myristate, butyl palmitate, propyl stearate, butyl stearate and the like.
    Type: Grant
    Filed: March 31, 1982
    Date of Patent: November 22, 1983
    Assignee: TDK Electronics Co. Ltd.
    Inventors: Kuniichi Yoda, Takehisa Ohkawa
  • Patent number: 4416948
    Abstract: A magnetic recording medium is provided which has smooth and stable running performances and is free of "squeal" phenomenon, especially in an environment of high temperature and high humidity. A highly viscous silicone oil having a viscosity of 100,000 centistokes or more is incorporated in combination with a higher fatty acid glycerine ester composed of a higher fatty acid having a melting point of 44.degree. C. or more and glycerine into a magnetic coating layer of the magnetic recording medium. Such silicone oil is represented by the general formula: ##STR1## wherein R is CH.sub.3, R' is CH.sub.3, C.sub.6 H.sub.5 or F and n is a number which determines a viscosity thereof. Such higher fatty glycerine ester is selected from monoglyceride of myristic acid, monoglyceride of palmitic acid, monoglyceride of stearic acid, monoglyceride of oleic acid and the like.
    Type: Grant
    Filed: March 31, 1982
    Date of Patent: November 22, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Takehisa Ohkawa, Kuniichi Yoda
  • Patent number: 4416709
    Abstract: The present invention relates to an amorphous magnetic alloy material suited for use as a core material of a magnetic head.When the magnetic head is subjected to a slide contact with a magnetic tape over a long period of time, a film of oxide and the like is formed on the surface of an amorphous magnetic alloy material due to chemically corrosive media frequently contained in the magnetic coating layer of the magnetic tape or due to carbon dioxide, water and the like contained in the air.The amorphous magnetic alloy material of the present invention is highly corrosion resistant due to the combination of chromium and platinum family element(s), and, the inconveniences in a magnetic head, due to chemical wear, can be prevented even where the magnetic head is operated or stored in a considerably severe condition.
    Type: Grant
    Filed: September 10, 1981
    Date of Patent: November 22, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Kazuo Ohya, Hiroki Fujishima, Norio Ishijima, Hiroyoshi Itoga, Yasuhiko Kominami
  • Patent number: 4415630
    Abstract: A magnetic recording medium comprises a substrate and a magnetic recording layer formed thereon and which is made of a magnetic coating material consisting essentially of a magnetic powder dispersed in a binder, the coating material containing a titanium coupling agent. The magnetic powder is coated with the coupling agent or is mixed with the agent and then dispersed in the binder. The binder is prepared by mixing and plasticizing a radiation-sensitive modified resin with a radiation-sensitive soft resin and subjecting the mixture to radiation cross-linking and polymerization. Process for producing the medium comprises coating the magnetic particles with the titanium coupling agent, blending the coated particles with the binder to form a magnetic coating material, and then applying the material to the substrate.
    Type: Grant
    Filed: February 28, 1983
    Date of Patent: November 15, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Yuichi Kubota, Masaharu Nishimatsu, Kazushi Tanaka
  • Patent number: 4414288
    Abstract: A magnetic recording medium which comprises a substrate coated with a magnetic paint which has a magnetic powder dispersed in a binder comprising a vinyl chloride - vinyl acetate copolymer containing at least 10% of polyvinyl alcohol, a urethane resin and a polyester resin.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: November 8, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Hiroshi Kawahara, Hitoshi Azegami, Eiji Horigome
  • Patent number: 4414289
    Abstract: A magnetic recording medium comprised of a nonmagnetic base and a magnetic coating layer thereon, said magnetic coating layer comprises ferromagnetic particles dispersed in a binder vehicle, characterized in that said magnetic coating layer contains a glyceride and a sorbitan ester of fatty acid.
    Type: Grant
    Filed: March 18, 1982
    Date of Patent: November 8, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Fujio Shibata, Kenji Hirabayashi, Chihoto Mikura
  • Patent number: 4412231
    Abstract: A light recording medium which has a substrate and a recording layer provided thereon and effects recording of information by selective removal or deformation of the recording layer by laser light, which is characterized by that said recording layer contains an organic dye as a light absorber, said dye is a mixed dye obtained by mixing a plurality of dyes having different light absorbing wavelengths from each other and the recording layer has a light absorptivity of 80% or more at all the wavelengths in the range of 400-900 nm in wavelength.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: October 25, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Kenryo Namba, Akihiko Kuroiwa, Shiro Nakagawa
  • Patent number: 4411957
    Abstract: A magnetic recording medium, consisting of a base coated with a magnetic coating material, uses as a binder a synthetic resin having a metal sulfonate group and a vinyl chloride-vinyl acetate copolymer containing not less than 8% vinyl alcohol, in which magnetic particles are dispersed. The binder may contain an isocyanate compound as a crosslinking agent for added particle durability.
    Type: Grant
    Filed: August 27, 1982
    Date of Patent: October 25, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Fukunori Tokuda, Yutaka Nakashima
  • Patent number: 4410406
    Abstract: A magnetic recording medium is prepared by forming a thin magnetic layer having the formulation(Co.sub.100-x Ni.sub.x).sub.100-y P.sub.ywherein x is in a range of 0 to 35 wt. % and y is in a range of more than 0 wt. % to 6 wt. % on a non-magnetic substrate by a sputtering method.
    Type: Grant
    Filed: November 12, 1981
    Date of Patent: October 18, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Osamu Kohmoto, Takahiro Yamamoto
  • Patent number: 4410139
    Abstract: A liquid nebulizer comprising a nebulizing container for a liquid, an outlet duct, and a transducer at the bottom of the container. A partition surrounding the liquid projection produced by the transducer is included, having its upper edge above the liquid surface, so that large spray particles or drops from the outlet duct fall outside the partition.
    Type: Grant
    Filed: May 8, 1978
    Date of Patent: October 18, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Kyoichi Nishikawa, Sadao Mitsui
  • Patent number: 4410590
    Abstract: A magnetic recording medium comprises a lower magnetic layer containing a magnetic powder having a coercive force of 700 Oe or higher dispersed in an organic binder which is coated on a non-magnetic substrate and an upper magnetic layer containing a magnetic powder having a coercive force higher than the coercive force of said lower magnetic la
    Type: Grant
    Filed: October 14, 1981
    Date of Patent: October 18, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Hiroshi Kawahara, Hitoshi Azegami, Eiji Horigome
  • Patent number: 4409300
    Abstract: A magnetic recording medium is provided which has smooth and stable running performances and is free of "squeal" phenomenon, especially in an environment of high temperature and high humidity. A highly viscous silicone oil having a viscosity of 100,000 centistokes or more is incorporated in combination with a sorbitan fatty acid ester into a magnetic coating layer of the magnetic recording medium. Such silicone oil is represented by the general formula: ##STR1## wherein R is CH.sub.3, R' is CH.sub.3, C.sub.6 H.sub.5 or F and n is a number which determines a viscosity thereof. Such sorbitan fatty acid ester is selected from sorbitan monopalmitate, sorbitan monostearate, sorbitan distearate, sorbitan tristearate, sorbitan monooleate and the like.
    Type: Grant
    Filed: March 31, 1982
    Date of Patent: October 11, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Takehisa Ohkawa, Kuniichi Yoda
  • Patent number: 4408171
    Abstract: A noise filter with a socket attached thereto including a case made of metallic material mounting a pair of pierce type (feed through) capacitors and a power input socket having a pair of power input contacts and a grounding contact, a choke coil having a pair of coil windings wound thereabout and a capacitor interposed between said pair of coil windings mounted inside said case, said pierce type capacitors including inner piercing (feed through) terminals and outer terminals, said power input contacts and the piercing terminals of said pierce type capacitors being connected to one another via said coil windings, and said grounding contact and the outer terminals of said pierce type capacitors being electrically connected to the case.
    Type: Grant
    Filed: March 13, 1981
    Date of Patent: October 4, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Tadaharu Akino, Akira Nakamura, Hiroyuki Uemura
  • Patent number: 4407000
    Abstract: A small sized reception antenna for VHF and/or UHF band for the use in a room has been found. The antenna has a horizontal dipole type first antenna portion having a folded elongated conductor, and a vertical second antenna portion having a ferrite pole electromagnetically coupled with said horizontal first antenna portion. Said horizontal first antenna portion is rotatable in a horizontal plane, while the second antenna portion is fixed vertically. A tank circuit with a tank coil wound on the ferrite pole and a variable capacitor is provided to resonate the antenna with the reception frequency. An output coil is wound on the ferrite pole, and said output coil provides the output signal of the present antenna. Means for sliding the output coil along the ferrite pole is provided to adjust the output impedance of the present antenna for each of the reception frequencies.
    Type: Grant
    Filed: June 25, 1981
    Date of Patent: September 27, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Masanori Sasaki, Isao Yokoyama
  • Patent number: 4404245
    Abstract: A protective sheet for a cassette holding a magnetic recording tape comprises a transparent base which is coated with a hardened surface layer formed by bonding hard fine particles with a binder.
    Type: Grant
    Filed: May 14, 1981
    Date of Patent: September 13, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Toshihiko Ishida
  • Patent number: 4404029
    Abstract: A D-E hysteresis loop of ferroelectrics known in the art has a square shape when the ferroelectrics are a BaTiO.sub.3 single crystal. Such ferroelectrics are used as a non-linear dielectric element of, for example a pulse generating device. The non-linear dielectric element according to the present invention consists of a polycrystal mainly composed of Ba(Ti.sub.0.90-0.98 Sn.sub.0.02-1.00)O.sub.3 and having an average grain diameter of from 10 to 60 .mu.m. The non-linearity is excellent and the temperature dependence of the non-linearity is considerably low.
    Type: Grant
    Filed: February 19, 1982
    Date of Patent: September 13, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Shoichi Iwaya, Hitoshi Masumura, Yoshifumi Midori, Yasunobu Oikawa, Hisao Abe
  • Patent number: 4404259
    Abstract: A magnetic recording medium having a substrate coated with a magnetic layer comprises a magnetic powder and a binder, essentially consisting of 40 to 80 wt. % of a polyester resin, 60 to 20 wt. % of a nitrocellulose impregnated with vinyl chloride-vinyl acetate copolymer as a protective component and a polyisocyanate.
    Type: Grant
    Filed: October 21, 1981
    Date of Patent: September 13, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Akihiko Hosaka, Yukihiro Isobe, Kiyotaka Okuyama
  • Patent number: 4404260
    Abstract: A magnetic recording medium, having formed on the surface of a non-magnetic substrate, a layer of the dispersion in a binder vehicle of magnetic particles having the surface thereof coated with a polyaminoamide phosphate.
    Type: Grant
    Filed: July 23, 1982
    Date of Patent: September 13, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Fujio Shibata
  • Patent number: 4401462
    Abstract: A metallic magnetic powder as fine metallic particles is produced by adsorbing zinc ion on iron oxyhydroxide in a alkaline bath with heating during or after the adsorption and then reducing it.
    Type: Grant
    Filed: April 1, 1981
    Date of Patent: August 30, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Akio Watanabe, Tosiaki Ide, Tatsuo Uehori
  • Patent number: 4400444
    Abstract: A magnetic recording medium having a ferromagnetic layer formed by oblique vapor deposition wherein the residual magnetic flux density in the width direction of the recording medium is larger than the residual magnetic flux density in the longitudinal direction shows the SN ratio in a practical level at recording in the width direction.
    Type: Grant
    Filed: June 3, 1982
    Date of Patent: August 23, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Toshiaki Izumi, Fumio Maruta, Takayoshi Kobuke, Kiyoshi Noguchi