Patents by Inventor Tahei Okada
Tahei Okada 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: 20160257902Abstract: Provided is a lubricating oil composition containing (A) 70 mass % or more and 95 mass % or less of a poly-?-olefin base oil, (B) 5 mass % or more and 20 mass % or less of an ester-based base oil, and (C) an ester-based defoaming agent, the poly-?-olefin base oil (A) being a polymer of an ?-olefin having 8 to 12 carbon atoms. The lubricating oil composition is able to keep excellent defoaming performance over a long period of time and is suitable as a step-up gear oil composition for wind power generation.Type: ApplicationFiled: October 30, 2014Publication date: September 8, 2016Applicant: IDEMITSU KOSAN CO., LTD.Inventors: Takuya ONO, Tahei OKADA
-
Patent number: 9410106Abstract: A lubricating oil composition containing a base oil having a kinematic viscosity at 40 degrees C. in a range from 10 mm2/s to 1000 mm2/s with: (A) at least one of phosphorus compounds represented by a formula (1) in an amount of 0.001 mass % to 0.3 mass % in terms of a phosphorus content; (B) at least one of a sulfur compound represented by a formula (2) and a sulfur compound that comprises a dithio (—S—S—) bond in a molecule in an amount of 0.01 mass % to 0.5 mass % in terms of a sulfur content, the latter sulfur compound, when added to the base oil in an amount of 1 mass %, leading to a rating of 2 or lower in a copper strip corrosion test; and (D) a succinimide derivative in an amount of 0.01 mass % to 1 mass %.Type: GrantFiled: March 11, 2013Date of Patent: August 9, 2016Assignee: IDEMITSU KOSAN CO., LTD.Inventors: Yumiko Kiko, Tahei Okada
-
Patent number: 9139795Abstract: A biodegradable lubricating oil composition includes (A) an ester represented by a formula (1) below, the ester having a kinematic viscosity in a range from 300 mm2/s to 1000 mm2/s at 40 degrees C. and an acid value of 0.5 mgKOH/g or less; (B) an ester being obtained by reacting a straight-chain saturated aliphatic carboxylic acid with a polyhydric alcohol, the ester having an acid value of 0.5 mgKOH/g or less; and (C) a phosphate amine salt being obtained by reacting an acidic phosphate with an alkylamine. In the formula, Ra is a hydrocarbyl group having 4 to 20 carbon atoms, Rb is a hydrocarbyl group having 4 to 18 carbon atoms, Rc is an acyl group having 1 to 10 carbon atoms, and n is an integer of 3 to 15.Type: GrantFiled: May 14, 2010Date of Patent: September 22, 2015Assignee: IDEMITSU KOSAN CO., LTD.Inventors: Tahei Okada, Yukitoshi Fujinami, Takuya Ohno
-
Patent number: 9068136Abstract: A lubricating oil composition for high-temperature applications contains (A) a pyromellitate ester, (B) a sulfur-containing triazine antioxidant, and (C) a thiophosphoric acid ester antioxidant. When the lubricating oil composition for high-temperature applications according to the invention is applied to a chain, a gear, a bearing and the like, an amount of evaporation of the lubricating oil composition is restrained for a long time and fluidity thereof is also kept for a long time.Type: GrantFiled: March 17, 2011Date of Patent: June 30, 2015Assignee: IDEMITSU KOSAN CO., LTD.Inventors: Takuya Ohno, Tahei Okada, Hideto Kamimura
-
Patent number: 8987177Abstract: A biodegradable lubricating oil composition includes (A) an ester being obtained by reacting a saturated aliphatic carboxylic acid, a straight-chain aliphatic dicarboxylic acid and a polyhydric alcohol together, the ester having a kinematic viscosity in a range from 400 mm2/s to 1000 mm2/s at 40 degrees C. and an acid value of 0.5 mgKOH/g or less; (B) an ester being obtained by reacting a straight-chain saturated aliphatic carboxylic acid with a polyhydric alcohol, the ester having an acid value of 0.5 mgKOH/g or less; and (C) a phosphate amine salt being obtained by reacting an acidic phosphate with an alkylamine.Type: GrantFiled: May 6, 2010Date of Patent: March 24, 2015Assignee: Idemitsu Kosan Co., Ltd.Inventors: Tahei Okada, Yukitoshi Fujinami, Takuya Ohno
-
Publication number: 20150051128Abstract: A lubricating oil composition containing a base oil having a kinematic viscosity at 40 degrees C. in a range from 10 mm2/s to 1000 mm2/s with: (A) at least one of phosphorus compounds represented by a formula (1) in an amount of 0.001 mass % to 0.3 mass % in terms of a phosphorus content; (B) at least one of a sulfur compound represented by a formula (2) and a sulfur compound that comprises a dithio (—S—S—) bond in a molecule in an amount of 0.01 mass % to 0.5 mass % in terms of a sulfur content, the latter sulfur compound, when added to the base oil in an amount of 1 mass %, leading to a rating of 2 or lower in a copper strip corrosion test; and (D) a succinimide derivative in an amount of 0.01 mass % to 1 mass %.Type: ApplicationFiled: March 11, 2013Publication date: February 19, 2015Applicant: IDEMITSU KOSAN CO., LTD.Inventors: Yumiko Kiko, Tahei Okada
-
Patent number: 8703678Abstract: A grease which comprises a base oil containing at least 50% by mass of a diester compound having a total carbon number of 28 to 40 and represented by the general formula (I): R1OOC—(R2)n—COOR3??(I) wherein R1 and R3 each independently represent a C4 to C20 monovalent aliphatic hydrocarbon group, R2 represents a C1 to C20 divalent hydrocarbon group and n is 0 or 1. The grease is excellent in both low-temperature performance and high-temperature performance and has low oil separation tendency even under high centrifugal force (acceleration). In particular, when the grease is used in a rotational transmission device having a built-in one-way clutch, the grease can provide satisfactory clutch engagement property (intermeshing ability) at low temperatures and a prolonged bearing life at high temperatures and is less apt to cause oil separation under high centrifugal force.Type: GrantFiled: October 5, 2007Date of Patent: April 22, 2014Assignee: Idemitsu Kosan Co., Ltd.Inventors: Yukitoshi Fujinami, Tahei Okada, Shinya Nakatani, Atsushi Yokouchi
-
Publication number: 20140051618Abstract: The lubricating oil composition contains a base oil; (A) an acidic alkyl phosphate ester having a C6 to C20 alkyl group; (B) a dialkylamine and/or a trialkylamine; and (C) (c-1) a sulfur compound in an amount of 0.2 to 0.6 mass % as reduced to S, the sulfur compound containing no poly-sulfur bond which is equal to or longer than —S—S—S— in a molecule thereof and having an S content of the molecule of 15 mass % or more and (c-2) an optional thiophosphoric acid trihydrocarbyl ester in an amount of 0.1 to 1.0 mass %, the ester being represented by formula (I): (R—O—)3P?S??(I) (wherein R represents a C6 to C20 hydrocarbyl group) and having a P content of the composition of 150 to 500 ppm by mass The lubricating oil composition has excellent anti-seizure performance, excellent anti-fatigue performance (e.g., anti-FZG-micropitting performance), and reduced sludge formation in an oxidation test.Type: ApplicationFiled: October 25, 2013Publication date: February 20, 2014Applicant: IDEMITSU KOSAN CO., LTD.Inventor: Tahei OKADA
-
Patent number: 8609596Abstract: To provide a gear oil composition containing a base oil, and compounded therein, (A) an ashless dithiocarbamate compound and (B) an ester of pentaerythritol and a C12 to C20 branched fatty acid, the ester having a hydroxyl value of 20 to 100 mg KOH/g. The gear oil composition has a high transmission efficiency and shows both of resistance to sludge formation and extreme pressure property.Type: GrantFiled: March 19, 2008Date of Patent: December 17, 2013Assignee: Idemitsu Kosan Co., Ltd.Inventors: Tahei Okada, Shigeo Hara
-
Patent number: 8394749Abstract: The present invention provides a pressure-medium oil comprising at least one of a hydrocarbon compound and an ether compound and having the following properties (1) to (4): (1) a kinematic viscosity as measured at 40° C. of 2 to 30 mm2/s; (2) a viscosity index of 110 or higher; (3) a density as measured at 15° C. of 0.86 g/cm3 or less; and (4) a pour point of ?50° C. or lower. The pressure-medium oil does not solidify under an ultra-high pressure, for example, 1.5 GPa or higher, and has a low pour point and excellent compatibility with test samples and with the material of the apparatus employed in the test.Type: GrantFiled: October 30, 2006Date of Patent: March 12, 2013Assignee: Idemitsu Kosan Co., Ltd.Inventors: Shoji Aoyama, Keizo Murata, Hiroshi Nagakawa, Tahei Okada
-
Publication number: 20130012417Abstract: A lubricating oil composition for high-temperature applications contains (A) a pyromellitate ester, (B) a sulfur-containing triazine antioxidant, and (C) a thiophosphoric acid ester antioxidant. When the lubricating oil composition for high-temperature applications according to the invention is applied to a chain, a gear, a bearing and the like, an amount of evaporation of the lubricating oil composition is restrained for a long time and fluidity thereof is also kept for a long time.Type: ApplicationFiled: March 17, 2011Publication date: January 10, 2013Applicant: IDEMITSU KOSAN CO., LTD.Inventors: Takuya Ohno, Tahei Okada, Hideto Kamimura
-
Publication number: 20130012416Abstract: Provided are a grease composition which inhibits simultaneously a bearing wear and a fretting wear under a high load to make it possible to elongate a life of the bearing; a grease composition which can inhibit a fretting wear caused by a change in a load in a thrust direction in addition to an usual fretting wear caused by small vibration in an oscillating direction; and a grease composition which is excellent in low-temperature characteristics. The grease compositions contain a base oil and a thickener, wherein the base oil contains a poly-?-olefin (component A) which has a kinetic viscosity of 300 mm2/s or more at 40° C. and which is produced by using a metallocene catalyst.Type: ApplicationFiled: March 25, 2011Publication date: January 10, 2013Applicant: IDEMITSU KOSAN CO., LTD.Inventors: Yukitoshi Fujinami, Tahei Okada, Takuya Ono
-
Publication number: 20120065111Abstract: A biodegradable lubricating oil composition includes (A) an ester represented by a formula (1) below, the ester having a kinematic viscosity in a range from 300 mm2/s to 1000 mm2/s at 40 degrees C. and an acid value of 0.5 mgKOH/g or less; (B) an ester being obtained by reacting a straight-chain saturated aliphatic carboxylic acid with a polyhydric alcohol, the ester having an acid value of 0.5 mgKOH/g or less; and (C) a phosphate amine salt being obtained by reacting an acidic phosphate with an alkylamine. In the formula, Ra is a hydrocarbyl group having 4 to 20 carbon atoms, Rb is a hydrocarbyl group having 4 to 18 carbon atoms, Rc is an acyl group having 1 to 10 carbon atoms, and n is an integer of 3 to 15.Type: ApplicationFiled: May 14, 2010Publication date: March 15, 2012Applicant: IDEMITSU KOSAN CO., LTD.Inventors: Tahei Okada, Yukitoshi Fujinami, Takuya Ohno
-
Publication number: 20120053098Abstract: A biodegradable lubricating oil composition includes (A) an ester being obtained by reacting a saturated aliphatic carboxylic acid, a straight-chain aliphatic dicarboxylic acid and a polyhydric alcohol together, the ester having a kinematic viscosity in a range from 400 mm2/s to 1000 mm2/s at 40 degrees C. and an acid value of 0.5 mgKOH/g or less; (B) an ester being obtained by reacting a straight-chain saturated aliphatic carboxylic acid with a polyhydric alcohol, the ester having an acid value of 0.5 mgKOH/g or less; and (C) a phosphate amine salt being obtained by reacting an acidic phosphate with an alkylamine.Type: ApplicationFiled: May 6, 2010Publication date: March 1, 2012Applicant: IDEMITSU KOSAN CO., LTD.Inventors: Tahei Okada, Yukitoshi Fujinami, Takuya Ohno
-
Publication number: 20110275867Abstract: The invention provides a lubricating oil for gears which contains an ?-olefin polymer having a viscosity index of 175 or higher and which has a viscosity index of 170 or higher. The lubricating oil for gears which has high shear stability and high oxidation resistance and which prevents malfunction during start-up at low temperature.Type: ApplicationFiled: January 22, 2010Publication date: November 10, 2011Applicant: IDEMITSU KOSAN CO., LTD.Inventor: Tahei Okada
-
Publication number: 20100190670Abstract: A lubricating oil additive contains at least one steroid derivative selected from steroid saturated fatty acid ester, steroid carbonate ester and steroid ether. A lubricating oil composition added with the lubricating oil additive exhibits a low friction coefficient and excellent wear resistance, heat resistance and oxidation resistance stability.Type: ApplicationFiled: June 6, 2008Publication date: July 29, 2010Applicant: IDEMITSU KOSAN CO., LTD.Inventors: Hiroki Sekiguchi, Tahei Okada
-
Publication number: 20100113314Abstract: To provide a gear oil composition containing a base oil, and compounded therein, (A) an ashless dithiocarbamate compound and (B) an ester of pentaerythritol and a C12 to C20 branched fatty acid, the ester having a hydroxyl value of 20 to 100 mg KOH/g. The gear oil composition has a high transmission efficiency and shows both of resistance to sludge formation and extreme pressure property.Type: ApplicationFiled: March 19, 2008Publication date: May 6, 2010Applicant: Idemitsu Kosan Co., LtdInventors: Tahei Okada, Shigeo Hara
-
Publication number: 20100035779Abstract: A grease which comprises a base oil containing at least 50% by mass of a diester compound having a total carbon number of 28 to 40 and represented by the general formula (I): R1OOC—(R2)n—COOR3 ??(I) wherein R1 and R3 each independently represent a C4 to C20 monovalent aliphatic hydrocarbon group, R2 represents a C1 to C20 divalent hydrocarbon group and n is 0 or 1. The grease is excellent in both low-temperature performance and high-temperature performance and has low oil separation tendency even under high centrifugal force (acceleration). In particular, when the grease is used in a rotational transmission device having a built-in one-way clutch, the grease can provide satisfactory clutch engagement property (intermeshing ability) at low temperatures and a prolonged bearing life at high temperatures and is less apt to cause oil separation under high centrifugal force.Type: ApplicationFiled: October 5, 2007Publication date: February 11, 2010Applicant: Idemitsu Kosan Co., LtdInventors: Yukitoshi Fujinami, Tahei Okada, Shinya Nakatani, Atsushi Yokouchi
-
Publication number: 20100009880Abstract: The lubricating oil composition contains a base oil; (A) an acidic alkyl phosphate ester having a C6 to C20 alkyl group; (B) a dialkylamine and/or a trialkylamine; and (C) (c-1) a sulfur compound in an amount of 0.2 to 0.6 mass % as reduced to S, the sulfur compound containing no poly-sulfur bond which is equal to or longer than —S—S—S— in a molecule thereof and having an S content of the molecule of 15 mass % or more and (c-2) an optional thiophosphoric acid trihydrocarbyl ester in an amount of 0.1 to 1.0 mass %, the ester being represented by formula (I): (R—O—)3P?S??(I) (wherein R represents a C6 to C20 hydrocarbyl group) and having a P content of the composition of 150 to 500 ppm by mass The lubricating oil composition has excellent anti-seizure performance, excellent anti-fatigue performance (e.g., anti-FZG-micropitting performance), and reduced sludge formation in an oxidation test.Type: ApplicationFiled: September 27, 2007Publication date: January 14, 2010Inventor: Tahei Okada
-
Publication number: 20090071870Abstract: The present invention provides a pressure-medium oil comprising at least one of a hydrocarbon compound and an ether compound and having the following properties (1) to (4): (1) a kinematic viscosity as measured at 40° C. of 2 to 30 mm2/s; (2) a viscosity index of 110 or higher; (3) a density as measured at 15° C. of 0.86 g/cm3 or less; and (4) a pour point of ?50° C. or lower. The pressure-medium oil does not solidify under an ultra-high pressure, for example, 1.5 GPa or higher, and has a low pour point and excellent compatibility with test samples and with the material of the apparatus employed in the test.Type: ApplicationFiled: October 30, 2006Publication date: March 19, 2009Applicant: Idemitsu Kosan Co., Ltd.Inventors: Shoji Aoyama, Keizo Murata, Hiroshi Nagakawa, Tahei Okada