Patents by Inventor Tamotsu Sobata

Tamotsu Sobata 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: 6090254
    Abstract: A process for coating a metallic molding article comprising transporting said article by conveyer means continuously and serially through a degreasing stage (1), a first water rinsing stage (2), a surface conditioning stage (3), a chemical conversion treatment stage (4), a second water rinsing stage (5), and an electrodeposition coating stage (6), wherein at least one stage of said stage (1), (2), (3), (4), (5) comprises in dipping said article in a treating bath of dipping system, at least one unit of said treating bath is provided with a vibratory agitation means, and the angles of immersion and emergence of said article with respect to said bath are not less than 25 degrees. The invention contributes to a curtailment of pre-treatment before coating and an effective elimination of adherent metal particles from the matallic article to provide a very satisfactory coating film.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: July 18, 2000
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Naohiko Sumie
  • Patent number: 5935919
    Abstract: An alkaline degreasing solution containing 0.01 to 3 g/l of alkali silicate calculated as Si concentration, and 0.01 to 10 g/l of a nonionic surfactant having an HLB value (=20.times.Mw/M, where Mw represents the weight of a hydrophilic group part and M represents the molecular weight of the surfactant) of 5 to 11 and a structure being expressed in the following general formula (I), with a pH value of at least 9.5:R--O--(EO).sub.m (AO).sub.n H (I)where R represents alkyl group, EO represents ethylene oxide group, AO represents alkylene oxide group (propylene oxide group and/or butylene oxide group), m represents an addition molar number of EO which is an integer of 3 to 7, n represents an addition molar number of AO which is an integer of 1 to 6, and m and n satisfy the relation of n<m .ltoreq.3n.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: August 10, 1999
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Mitsuo Shinomiya, Minoru Ishida, Shoji Shiraishi, Tamotsu Sobata
  • Patent number: 5925613
    Abstract: An alkaline degreasing solution containing 0.01 to 3 g/l of alkali silicate calculated as Si concentration, and 0.01 to 10 g/l of a nonionic surfactant having an HLB value (=20.times.Mw/M, where Mw represents the weight of a hydrophilic group part and M represents the molecular weight of the surfactant) of 5 to 11 and a structure being expressed in the following general formula (I), with a pH value of at least 9.5:R--O--(EO).sub.m (AO).sub.n H (I)where R represents alkyl group, EO represents ethylene oxide group, AO represents alkylene oxide group (propylene oxide group and/or butylene oxide group), m represents an addition molar number of EO which is an integer of 3 to 7, n represents an addition molar number of AO which is an integer of 1 to 6, and m and n satisfy the relation of n<m.ltoreq.3n.
    Type: Grant
    Filed: May 14, 1996
    Date of Patent: July 20, 1999
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Mitsuo Shinomiya, Minoru Ishida, Shoji Shiraishi, Tamotsu Sobata
  • Patent number: 5908512
    Abstract: The present invention provides a highly durable surface-conditioning agent for use in a pretreatment step for a phosphate coating treatment of metallic materials, which is an aqueous solution comprising 1 to 50 ppm of titanium ion, 50 to 1,000 ppm or phosphate ion, 50 to 400 ppm of tripolyphosphate ion and 20 to 1,500 ppm of carbonate ion, with a tripolyphosphate ion/titanium ion weight ratio of 10 to 100, and having a pH of 8.5 to 10.0.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: June 1, 1999
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Seiichiro Shirahata, Mitsuo Shinomiya, Tamotsu Sobata
  • Patent number: 5863357
    Abstract: Disclosed is a method for zinc phosphating a molded metal article wherein a treating bath composition comprises from 1.5 to 5.0 g/l of zinc ion, from 0.1 to 3.0 g/l of manganese ion, from 5 to 40 g/l of phosphate ion, from 0.05 to 3.0 g/l of a fluorine compound as HF and hydoxylamine as a chemical conversion accelerator. A concentration of hydroxylamine is maintained to satisfy the following relationship:0.5.ltoreq.?hydroxylamine!(g/l)-2.0.times.?Fe.sup.2+ !(g/l).ltoreq.3.0 The treating bath is agitated by a vibratory agitating means provided in the treating vessel so that a mean acceleration a of a treating solution present within a bath region in which the molded metal article is immersed to be treated under fluid agitation is at least 8 cm/sec.sup.2. The mean acceleration is calculated from the following equation: ##EQU1## wherein values of X, Y and Z, each in unit of cm/sec.sup.
    Type: Grant
    Filed: April 4, 1997
    Date of Patent: January 26, 1999
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Mitsuo Shinomiya, Masashi Takahashi, Satoshi Miyamoto, Tamotsu Sobata
  • Patent number: 5780122
    Abstract: A solution which is stored in a treatment bath is stirred by vibration stirring means provided in the treatment bath in a range of receiving a metal molded article or around a substantially horizontal surface of the metal molded article so that mean acceleration a expressed in the following equation is at least 8 cm/sec.sup.2 : ##EQU1## where X, Y and Z, which are in units of cm/sec.sup.2, represent average acceleration values of flow rate changes within 60 seconds, measured simultaneously in three axial directions of X, Y and Z which are perpendicular to each other at a measuring position.
    Type: Grant
    Filed: December 6, 1996
    Date of Patent: July 14, 1998
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Seiichiro Shirahata, Mitsuo Shinomiya, Satoshi Miyamoto, Tamotsu Sobata
  • Patent number: 5635465
    Abstract: An alkaline degreasing aqueous solution containing 0.01 to 10 g/l of a nonionic surface-active agent, and an organic substance exhibiting water solubility or water dispersibility at a pH value of at least 8, having a phenolic hydroxyl group with a molecular weight of at least 500, at a weight ratio of 0.1 to 2:1=(organic substance having a phenolic hydroxyl group):(nonionic surface-active agent). The alkaline degreasing aqueous solution has a pH value of at least 8.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: June 3, 1997
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Naohiko Sumie
  • Patent number: 5478529
    Abstract: A treatment solution which is stored in a treatment vessel is supplied to a mixing vessel and a simple fluoride solution is supplied into the mixing vessel from a simple fluoride supply vessel to convert aluminum salt of complex hydrofluoric acid which is contained in the treatment solution to complex hydrofluoric acid. Concentration of HF remaining in the mixed solution is measured with a metal silicon electrode meter provided in an HF concentration measuring part, so that a control signal is transmitted from a control unit to a pump and a flow control part on the basis of the data as obtained. The simple fluoride solution is supplied from the simple fluoride supply vessel to the treatment solution which is stored in the treatment vessel to return the activity of the treatment solution stored in the treatment vessel and to control the same in a prescribed range.
    Type: Grant
    Filed: April 22, 1994
    Date of Patent: December 26, 1995
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Katsuhiro Takeshita
  • Patent number: 5456810
    Abstract: A prescribed amount of a simple fluoride is added to a zinc phosphate treatment solution, which is a target solution, the HF concentration in the target solution is measured with a silicon electrode meter after the addition, and the concentration of the consumed HF is calculated to evaluate the activity of the target solution, for adding the simple fluoride to the zinc phosphate treatment solution so that its activity is in a control reference range.
    Type: Grant
    Filed: February 10, 1994
    Date of Patent: October 10, 1995
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Isao Kawasaki, Tamotsu Sobata
  • Patent number: 5399208
    Abstract: To treat an iron-based, zinc-based, and an aluminumbased surfaces etc. with zinc phosphate using the same solution, a treating solution is adjusted in concentrations so as to contain a simple fluoride in a range of 200.about.500 mg/l upon converting into a HF concentration and to contain a fluoride complex in a range shown in the following formula; ##EQU1## and also, it is adjusted in an active fluorine concentration so as to be 15.about.130 .mu.A at a value indicated by a silicon electrode meter. Instead of such adjusting, aluminum ions in the treating solution is precipitated in an outside of a treating bath to separate them from the treating solution and then, this treating solution may be returned in to the treating bath.
    Type: Grant
    Filed: February 1, 1993
    Date of Patent: March 21, 1995
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Akio Tokuyama, Shoji Shiraishi, Seiichiro Shirahata
  • Patent number: 5328526
    Abstract: A zinc phosphate coating film suitable for cationic electrodeposition coating and superior in both of coating film adhesion and corrosion resistance (especially, warm brine resistance and scab resistance) is formed by a conversion treatment of a metal surface using an acidic zinc-phosphating solution which does not contain a nickel ion as an essential component. The conversion treatment is carried out by bringing a metal surface into contact with a zinc-phosphating solution containing a zinc ion of 0.1 to 2.0 g/l, a phosphate ion of 5 to 40 g/l, a lanthanum compound of 0.001 to 3 g/l in terms of a lanthanum metal, and a phosphating accelerator, thereby the zinc phosphate coating film is formed on the metal surface.
    Type: Grant
    Filed: March 31, 1993
    Date of Patent: July 12, 1994
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Masahiro Jo, Yasutake Mino, Tamotsu Sobata
  • Patent number: 5308413
    Abstract: A metal surface is processed with dipping by a first zinc phosphating solution in which a fluoride complex and a simple fluoride are contained and a concentration of this simple fluoride is 200 to 300 mg/l on a basis converted into the HF concentration and that of the fluoride complex is in a mole ratio with the simple fluoride converted into the HF as shown as, [fluoride complex]/[simple fluoride].gtoreq.0.01, and then the surface is processed with spraying by a second zinc phosphating solution in which a simple fluoride concentration is 500 mg/l or less and higher than that in said first zinc phosphating solution.Thus, on a metal surface is formed a zinc phosphate coating film which is suitable for electrodeposition coating, particular for cationic electrodeposition coating, and superior in coating film adhesion, corrosion-resistance, particularly resistance for warm brine, and prevention of scab-corrosion.
    Type: Grant
    Filed: April 17, 1991
    Date of Patent: May 3, 1994
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Teturo Kishimoto, Minoru Ishida
  • Patent number: 5232523
    Abstract: The present inventin concerns a process for phosphating a metal surface comprising treating a metal surface with an acidic aqueous phosphate solution comprising zinc ion, phosphate ion, a phosphating accelerator and particular concentration of colloidal particles having an isoelectric point of 3 or less and an average particle diameter of 0.1.mu. or less, the metal surface being iron-based surface, zinc-based surface or combination thereof and the resulted phosphate coating being excellent in film adhesion, corrosion resistance and especially scab corrosion resistance.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: August 3, 1993
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Koetsu Endo, Akio Tokuyama, Tamotsu Sobata
  • Patent number: 5221370
    Abstract: A zinc phosphate film on a metal surface is used as a surface-protecting film and an under coating film for coating and so on. The zinc phosphate film is formed by treating a metal surface with an aqueous zinc phosphate solution. The aqueous zinc phosphate solution includes solutions containing a zinc ion in a concentration of more than 2 g/l to 20 g/l, a phosphate ion in a concentration of 5 g/l to 40 g/l, and at least one of silicotungstic acid and a silicotungstate in a concentration of 0.005 g/l to 20 g/l measured in terms of tungsten content.
    Type: Grant
    Filed: June 14, 1990
    Date of Patent: June 22, 1993
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Masahiro Jo, Yasutake Mino, Takamasa Shimizu, Koetsu Endo, Akio Tokuyama, Tamotsu Sobata
  • Patent number: 5211769
    Abstract: To treat an iron-based, zinc-based, and an aluminum-based surfaces etc. with zinc phosphate using the same solution, a treating solution is adjusted in concentrations so as to contain a simple fluoride in a range of 200.about.500 mg/l upon converting into a HF concentration and to contain a fluoride complex in a range shown in the following formula; ##EQU1## and also, it is adjusted in an active fluorine concentration so as to be 15.about.130 .mu.A at a value indicated by a silicon electrode meter. Instead of such adjusting aluminum ions in the treating solution is precipitated in an outside of a treating bath to separate them from the treating solution and then, this treating solution may be returned into the treating bath.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: May 18, 1993
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Akio Tokuyama, Shoji Shiraishi, Seiichiro Shirahata
  • Patent number: 5156687
    Abstract: It is required to undergo painting pretreatment of a plastic formings by a method which is replaceable of a vapor-washing method using a chlorinated hydrocarbon in order to prevent from the environmental destruction by the chlorinated hydrocarbon.A plastic formings is brought in contact and treated with a treating solution prepared by suspending a hydrocarbons solvent in water.A plastic formings is brought in contact and treated with a treating solution containing an alkali component and then, said treating solution attaching on the surface of said formings is rinsed out and, in at least a final stage of the rinsing-out, the surface of said formings is brought in contact with a surface-conditioning solution which contains a nonionic surface-active agent having the HLB value of 10 to 17 in a concentration range of 0.001 to 100 g/l.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: October 20, 1992
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Akira Ushio, Tamotsu Sobata, Kazuo Nobe
  • Patent number: 5039363
    Abstract: A process for phosphating the surfaces of iron-based metals, zinc-based metals or combination of such surfaces by treating the metal surfaces with an aqueous acidic zinc-phosphating solution comprising from about 0.1 to about 200 g/l of zinc ion, from about 5 to about 40 g/l of phosphate ion, from about 0.01 to 20.0 g/l as tungsten of soluble tungsten compound and a conversion coating accelerator. The metal surfaces thus phosphated with the solution are suitable for electrocoating.
    Type: Grant
    Filed: May 30, 1990
    Date of Patent: August 13, 1991
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Masahiro Jo, Yasutake Mino, Takamasa Shimizu, Koetsu Endo, Akio Tokuyama, Tamotsu Sobata
  • Patent number: 4994121
    Abstract: Corrosive resistant, coated laminate consisting of metal substrate, anti-corrosive layer and paint layer, which is characterized by the fact that the anti-corrosive layer is formed by a composition containing, as essential components, at least one hexa-valent chromium containing chromium compound having a solubility of 20 to 10.sup.-5 and aqueous silica and/or aqueous resin as binder, and as optional component, a water soluble chromium compound having a solubility of more than 20, and the paint layer is free from chromium compound. The laminate is excellent, inter alia, in adhesion of coating and anti-corrosive property. The invention also provides a coated metal plate having excellent corrosion resistance and continuous spot weldability.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: February 19, 1991
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Masaaki Takimoto, Yuichi Yoshida
  • Patent number: 4939034
    Abstract: Corrosive resistant, coated laminate consisting of metal substrate, anti-corrosive layer and paint layer, which is characterized by the fact that the anti-corrosive layer is formed by a composition containing, as essential components, at least one hexa-valent chromium containing chromium compound having a solubility of 20 to 10.sup.-5 and aqueous silica and/or aqueous resin as binder, and as optional component, a water soluble chromium compound having a solubility of more than 20, and the paint layer is free from chromium compound. The laminate is excellent, inter alia, in adhesion of coating and anti-corrosive property. The invention also provides a coated metal plate hving excellent corrosion resistance and continuous spot weldability.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: July 3, 1990
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Masaaki Takimoto, Yuichi Yoshida
  • Patent number: 4853285
    Abstract: Corrosive resistant, coated laminate consisting of metal substrate, anti-corrosive layer and paint layer, which is characterized by the fact that the anti-corrosive layer is formed by a composition containing, as essential components, at least one hexa-valent chromium containing chromium compound having a solubility of 20 to 10.sup.-5 and aqueous silica and/or aqueous resin as binder, and as optional component, a water soluble chromium compound having a solubility of more than 20, and the paint layer is free from chromium compound. The laminate is excellent, inter alia, in adhesion of coating and anti-corrosive property. The invention also provides a coated metal plate having excellent corrosion resistance and continuous spot weldability.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: August 1, 1989
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Masaaki Takimoto, Yuichi Yoshida