公开(公告)号：JPH07266493A

公开(公告)日：1995-10-17

申请号：JP24128494

申请日：1994-10-05

Applicant: MITSUI TOATSU CHEMICALS

Inventor： KIJIMA SHIGEKI ,  TAGAWA KIMITERU ,  KOBAYASHI YOSHITAKE ,  KABETANI TOSHIHIKO ,  YAMAMURA TAKESHI ,  OTSUBO EIJI

IPC: B32B15/088 ,  B32B15/08 ,  H05K3/38

Abstract: PURPOSE:To obtain a workpiece of a metallic plate coated with a thermoplastic polyimide having excellent heat resistance which can be easily punched, cut, drilled, notched, etched, polished, plated, bent or drawn, and further to obtain a secondary workpiece formed by attaching with heat and pressure the metallic plate and a matter to be attached through the thermoplastic polyimide as an adhesive. CONSTITUTION:A metallic plate is coated with a thermoplastic polyimide obtained by means of polycondensation of at least one diamine out of 1,3-bis(3- aminophenoxy)benzene, 4,4'-bis(3-aminophenoxy)biphenyl and 3,3'- diaminobenzophenone and at least one tetracarboxylic acid dianhydride out of 3,-3',4,4'-diphenylether tetracarboxylic acid dianhydride, 3,-3',4,4'-benzophenone tetracarboxylic acid dianhydride, and 3,3',4, 4'-biphenyl tetracarboxylic acid dianhydride. By using the metallic plate, a workpiece and a secondary workpiece are obtained.

公开(公告)号：JPH0471321B2

公开(公告)日：1992-11-13

申请号：JP17930083

申请日：1983-09-29

Applicant: MITSUI TOATSU CHEMICALS

Inventor： KOBAYASHI SADAO ,  OOSHIMA KAZUFUMI ,  SUDO KAZUTO ,  TAGAWA KIMITERU

IPC: B22F9/22 ,  C09D5/23 ,  C09D7/12 ,  C09D177/00 ,  G11B5/706 ,  H01F1/06

公开(公告)号：JPH04219323A

公开(公告)日：1992-08-10

申请号：JP41059590

申请日：1990-12-14

Applicant: MITSUI TOATSU CHEMICALS

Inventor： IWASAKI KOZO ,  TAGAWA KIMITERU ,  HASHIMOTO MITSUYOSHI

IPC: C01G49/02 ,  H01F1/11

Abstract: PURPOSE:To provide a process for producing an acicular goethite having small axial ratio and uniform particle size distribution. CONSTITUTION:Acicular crystal of goethite having an axial ratio (L/D) of 5-6 and uniform particle size distribution (sigmaL/L=0.4 to 0.5) can be produced by continuously mixing and reacting an aqueous solution of a ferrous salt with an aqueous solution of an alkali using a line mixer, quickly mixing an oxidizing gas into the reaction mixture in the subsequent line mixer to quickly oxidize 7-15% of the hydroxide formed by the former reaction, charging the obtained reaction mixture into a subsequent post-reactor and introducing oxidizing gas into the reactor to complete the reaction.

公开(公告)号：JPH04205912A

公开(公告)日：1992-07-28

申请号：JP33003490

申请日：1990-11-30

Applicant: MITSUI TOATSU CHEMICALS

Inventor： TAGAWA KIMITERU ,  TAKAHASHI SEIICHI ,  KOBA SHIGEO ,  SUDA SATORU

IPC: G11B5/712 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/06

Abstract: PURPOSE:To obtain a magnetic recording medium fit for high density magnetic recording by using ferromagnetic metal particles surfacecoated with a ferrite compd. contg. Fe, Co and at least one kind of metal such as Cu and having spinel structure. CONSTITUTION:Ferromagnetic metal particles surface-coated with a ferrite compd. contg. Fe, Co and at least one kind of metal selected among Zn, Ni, Mn, Al, Cr and Cu and having spinel structure are used. The particles have satisfactory oxidation stability and maintain high saturation magnetization even in deteriorated environment or after a weather resistance test. When a magnetic layer is formed with the particles and a binder, a high rate of filling of the particles is attained in the magnetic layer and a magnetic recording medium having superior oxidation stability, maintaining high saturation magnetization and fit for high density recording can be obtd.

公开(公告)号：JPH0366727B2

公开(公告)日：1991-10-18

申请号：JP4919882

申请日：1982-03-29

Applicant: MITSUI TOATSU CHEMICALS

Inventor： OZAWA HIROSHI ,  OBARA YOSHIAKI ,  TAGAWA KIMITERU

IPC: C09D5/23 ,  C09D175/00 ,  C09D175/04 ,  G11B5/702

公开(公告)号：JPH02204333A

公开(公告)日：1990-08-14

申请号：JP1984689

申请日：1989-01-31

Applicant: MITSUI TOATSU CHEMICALS

Inventor： TAGAWA KIMITERU ,  HAYASHI FUJIO ,  UTSUNO NORITOSHI

IPC: C01G49/00 ,  H01F1/11

Abstract: PURPOSE:To improve dispersibility in a resin binder by hydrolyzing a soln. of alcohol-soluble ferric salts in alcohol and heating the resulting sol. CONSTITUTION:Alcohol-soluble ferric salts (e.g. FeCl2) are dissolved in alcohol (e.g. methanol) and alcohol-soluble salts of one or more among Ba, Sr, Pb, Co, Ni and Ti (e.g. BaCl2) are further dissolved as required. Water is added to the resulting soln. and this soln. is hydrolyzed to obtain a sol. This sol and alcohol are heated at 150-600 deg.C for 0.5-20hr to obtain fine iron-based oxide particles in the form of hexagonal platy magnetic oxide particles contg. at least one among Ba, Br, Pb, Co, Ni and Ti and having magnetoplumbite structure.

公开(公告)号：JPS63184308A

公开(公告)日：1988-07-29

申请号：JP19825487

申请日：1987-08-10

Applicant: MITSUI TOATSU CHEMICALS

Inventor： TAGAWA KIMITERU ,  HIRAMATSU MASANOBU

IPC: B22F1/02 ,  C09D5/23 ,  C09D7/12 ,  G11B5/712 ,  H01F1/06

Abstract: PURPOSE:To obtain highly stable ferromagnetic metal powder by immersing ferromagnetic metal powder in an organic solvent dissolving Al alkoxide compound or/and Al alkyl compound and thereafter precipitating and depositing Al compound on the ferromagnetic metal powder with addition of methanol. CONSTITUTION:The Al alkoxide compound and Al alkyl compound do not show particularly strong bindability to the ferromagnetic metal power even when such powder is immersed into an organic solvent under the condition that such compounds are dissolved into the solvent. However, with addition of methanol, Al(OCH3)3 is generated by replacing reaction between alkoxi group or alkyl group and methoxy group and it is uniformly deposited to the ferromagnetic metal particle surface. As the Al alkoxide compound, Al(OC2H5)3, Al(iso-OC3H7)3, Al(sec-OC4H9)3 may be used and as Al alkyl compound, Al(CH3)3, Al(C2H5)3, Al(C3H7)3, Al(C4H9)3 may be used.

公开(公告)号：JPS63184306A

公开(公告)日：1988-07-29

申请号：JP19825287

申请日：1987-08-10

Applicant: MITSUI TOATSU CHEMICALS

Inventor： TAGAWA KIMITERU ,  HIRAMATSU MASANOBU

IPC: B22F1/02 ,  C09D5/23 ,  C09D7/12 ,  G11B5/712 ,  H01F1/06

Abstract: PURPOSE:To obtain highly stable ferromagnetic metal powder by immersing ferromagnetic metal powder in an organic solvent dissolving Al alkoxide compound or/and Al alkyl compound, precipitating and depositing the Al compound on the ferromagnetic metal powder through addition of methanol and giving heat treatment to the powder. CONSTITUTION:As the Al alkoxide compound or Al alkyl compound to be used, any kind of compounds which are not easily combined with ferromagnetic metal particles and easily dissolve in an ordinary organic solvent dissolving methanol such as toluene and heptane can be used. For example, as the Al alkoxide compound, Al(OC2H5)3, Al(iso-OC3H7)3, Al(sec-OC4H9)3, etc., can be used, and as the Al alkyl compound, Al(CH3)3, Al(C2H5)3, Al(C3H7)3, Al(C4H9)3, etc., can be used. The heat treatment must be conducted in an inactive gas atmosphere, in hydrogen gas, or in a reducing gas atmosphere mainly composed of hydrogen.

公开(公告)号：JPS6362803A

公开(公告)日：1988-03-19

申请号：JP20510386

申请日：1986-09-02

Applicant: MITSUI TOATSU CHEMICALS

Inventor： SUDOU KAZUFUYU ,  OSHIMA KAZUFUMI ,  TAGAWA KIMITERU

IPC: B22F9/22

Abstract: PURPOSE:To provide a material for magnetic recording having superior magnetic characteristics and oxidation stability by coating the surface of iron or an iron-base compd. with an amorphous Al compd. or an amorphous Al-base compd. and carrying out reduction under heating. CONSTITUTION:An iron-base compd. such as needlelike iron oxyhydroxide is synthesized by hydrolyzing a ferrous sulfate soln. and sodium hydroxide. The iron oxyhydroxide is diluted with water and stirred. The surface is coated with an amorphous Al compd. such as sodium aluminate or aluminum sulfate, and reduction is carried out under heating in a flow of hydrogen or a hydrogen- base gas to form metallic powder. Thus, ferromagnetic metallic powder can be formed and a material for magnetic recording having superior oxidation stability can be provided.

公开(公告)号：JPS6333510A

公开(公告)日：1988-02-13

申请号：JP17670986

申请日：1986-07-29

Applicant: MITSUI TOATSU CHEMICALS

Inventor： TSUMURA RYUICHIRO ,  OSHIMA KAZUFUMI ,  TAGAWA KIMITERU ,  MURAISHI TERUO

IPC: B22F9/26

Abstract: PURPOSE:To produce high purity fine hexagonal cobalt particles in a high yeld by reducing a cobalt monocarboxylate with pressurized hydrogen at a specified temp. in water as a solvent in the presence of a surfactant. CONSTITUTION:A cobalt monocarboxylate such as cobalt formate or cobalt acetate is dissolved in ion exchanged water as a solvent to prepare a soln. having about 1-50wt% concn. A surfactant such as sodium dodecylbenzenesulfonate is added to the soln. by about 0.01-1wt% of the amount of the solvent and the cobalt monocarboxylate is reduced with pressurized hydrogen at 150-300 deg.C. The reaction is carried out for about 0.1-10hr with stirring under about 5-200kg/cm pressure of hydrogen. Thus, high purity fine hexagonal cobalt particles are obtd. in about 100% reaction yield. The cobalt particles are suitable for use as a magnetic material for a vertical magnetic recording medium.