Patents by Inventor Tamiji Kamakura

Tamiji Kamakura 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: 6379581
    Abstract: A lubricant for use in a refrigerator which operates with a chlorine-free Flon (fluorocarbon)-type refrigerant whose molecules do not contain chlorine. The lubricant contains a synthetic oil, and molybdenumoxysulfide diorganophosphorodithioate given by the following formula (1) and/or molybdenumoxysulfide diorganodithiocarbamate given by the following formula (2), the content of the compounds of formulae (1) and (2) in total ranges from 0.1 to 10 wt % to the content of the synthetic oil: {(RO)2PS2}2Mo2SXOY  (1) where R represents a hydrocarbon group having 3 to 20 carbon atoms, and X and Y are numbers which meet the conditions of O≦X≦4, 0≦Y≦4 and X+Y=4; and (R′2NCS2)2Mo2SX′OY′  (2) where R′ is a hydrocarbon group having 3 to 20 carbon atoms and X′ and Y′ are numbers which meet the conditions of )≦X′≦4, 0≦Y′≦4 and X′+Y′=4.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: April 30, 2002
    Assignee: Asahi Denka Kogyo, K.K.
    Inventors: Tamiji Kamakura, Noriyoshi Tanaka, Kimiyoshi Namiwa, Yukio Tatsumi, Masato Namiki
  • Patent number: 6217791
    Abstract: The object of the present invention is to provide a lubricant for refrigerators having good compatibility with chlorine-free Flon-type coolants, good lubricity and resistant to hygroscopicity and a composition for refrigerators using this lubricant. This lubricant contains a monomethylether of polyoxyethyleneoxypropyleneglycol where the end group at the hydrogen terminal is an oxyethylene group, represented by the following general formula (1): CH3O(AO)m(CH2CH2O)nH wherein the AO group represents oxypropylene group, or copolymeric group of oxypropylene groups and oxyethylene groups wherein the copolymeric form may be a block type and/or a random type, m is a number of 1≦m≦50, n is a number of 1≦n≦10, and the content of the oxyethylene group in the compound ranges from 5 to 60 percent by weight. A composition for refrigerators using said lubricant is also provided.
    Type: Grant
    Filed: December 17, 1992
    Date of Patent: April 17, 2001
    Assignee: Asahi Denka Kogyo K.K.
    Inventors: Tamiji Kamakura, Noriyoshi Tanaka, Yuji Baba, Kimiyoshi Namiwa, Yukio Tatsumi, Masato Namiki
  • Patent number: 5620950
    Abstract: The objective of the present invention resides in providing a lubricant for refrigerators that reacts rapidly with free acids and contains a stabilizer that has good compatibility with a chlorine-free Flon-thpe coolant such as Flon 134a and the like whose molecules do not contain chlorine. The lubricant for refrigerators employing a chlorine-free Flon-type coolant in accordance with the present invention 100 parts by weight of a synthetic oil and is compounded with 0.05 to 15 parts by weight of an alicyclic epoxy compound having one or more functional groups represented by the following formula: ##STR1## (wherein R.sub.1 and R.sub.2 independently represent a hydrogen or methyl group, and may be the same or different).
    Type: Grant
    Filed: August 8, 1995
    Date of Patent: April 15, 1997
    Assignee: Asahi Denka Kogyo K.K.
    Inventors: Tamiji Kamakura, Noriyoshi Tanaka, Kimiyoshi Namiwa, Yukio Tatsumi, Masato Namiki
  • Patent number: 5612297
    Abstract: A grease composition comprising 0.1 to 10 parts by weight of a powdered molybdenum oxysulfide dithiocarbamate composition which comprises a compound represented by the following formula: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independent hydrocarbyl groups and may be the same or different groups, and the total number of carbon atoms contained in R.sup.1 to R.sup.4 is 4 to 36; and wherein X is sulfur or oxygen and the composition of the total of all Xs is given as S.sub.m and O.sub.n in which m and n satisfy the ranges of 1.7.ltoreq.m.ltoreq.3.5 and 0.5.ltoreq.n.ltoreq.2.3, respectively, in which the constituent particles have diameters of not larger than 50 .mu.m, based on 100 parts by weight of a base grease.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: March 18, 1997
    Assignee: Asahi Denka Kogyo K.K.
    Inventors: Tamiji Kamakura, Noriyoshi Tanaka, Aritoshi Fukushima, Yukio Tatsumi, Kazuhisa Morita
  • Patent number: 5498356
    Abstract: The present invention relates to a lubricated refrigerant for use in refrigerators employing hydrofluorocarbon coolants such as R 134a, R 32, R 125 and the like. The lubricated refrigerant contains fluorocarbon coolant, synthetic oil and a carbodiimide compound represented by the following general formula. R.sub.1 --N.dbd.C.dbd.N--R.sub.2, wherein R.sub.1 and R.sub.2 represent hydrogen atoms or hydrocarbly groups or nitrogen and/or oxygen containing hydrocarbly groups, and R.sub.1 and R.sub.2 may be the same or different groups. The refrigerant composition according to the present invention preferably contains said hydrofluorocarbon coolant and said lubricant at a given blending ratio.
    Type: Grant
    Filed: November 18, 1994
    Date of Patent: March 12, 1996
    Assignee: Asahi Denka Kogyo K.K.
    Inventors: Tamiji Kamakura, Noriyoshi Tanaka, Kimiyoshi Namiwa, Yukio Tatsumi, Masato Namiki, Hideo Yokobori
  • Patent number: 5494608
    Abstract: A powdery molybdenum oxysulfide dithiocarbamate composition which comprises a compound represented by the following general formula (1): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independent hydrocarbyl groups and may be the same or different groups, and the total number of carbon atoms contained in R.sup.1 to R.sup.4 is 4 to 36; and wherein X is sulfur or oxygen and the composition of the total of all Xs is given as S.sub.m O.sub.n in which n and m satisfy the ranges of 1.7.ltoreq.m.ltoreq.3.5 and 0.5.ltoreq.n.ltoreq.2.3, respectively, and in which the constituent particles have diameters of not larger than 50 .mu.m. The present invention also relates to a process for production of the composition and a grease composition containing the same.
    Type: Grant
    Filed: August 2, 1994
    Date of Patent: February 27, 1996
    Assignee: Asahi Denka Kogyo K.K.
    Inventors: Tamiji Kamakura, Noriyoshi Tanaka, Aritoshi Fukushima, Yukio Tatsumi, Kazuhisa Morita
  • Patent number: 5032305
    Abstract: A lubricant composition for refrigerators using Flon 134a comprises at least 80 percent by weight of a specific type of polyoxethylene glycol dialkyl ether having a kinematic viscosity of 6 to 500 cSt at 40 degree centigrade.
    Type: Grant
    Filed: April 13, 1990
    Date of Patent: July 16, 1991
    Assignee: Asahi Denka Kogyo K.K.
    Inventors: Tamiji Kamakura, Yuzi Baba, Kimiyoshi Namiwa
  • Patent number: 4789492
    Abstract: Disclosed is a novel sulfidoxymolybdenum dialkylphosphorodithioate represented by the following general formula (I): ##STR1## wherein R stands for a secondary alkyl group having 4 to 30 carbon atoms and four R's may be the same or different, and X stands for O or S and four X's may be the same or different.This compound is very valuable as the lubricant additive.
    Type: Grant
    Filed: March 21, 1986
    Date of Patent: December 6, 1988
    Assignee: Asahi Denka Kogyo K.K.
    Inventors: Shigeru Katsumata, Takuro Handa, Tamiji Kamakura, Noriyoshi Tanaka, Hidekatsu Katoh, Kimiyoshi Namiwa, Yoshikazu Shoji