The invention discloses a method for preparing a flaky iron oxide. The flaky iron oxide is obtained through a vacuum coating machine. The vacuum coating machine includes a vacuum pump, a vacuum pipeline arrangement, a vacuum coating chamber, a flaky iron oxide supporting chamber and an electrical discharging gas inlet. High-energy particles generated by an iron oxide target are deposited on the surface of the conveying belt; and then the flaky iron oxide on a conveying belt is stripped and calcined to obtain the flaky iron oxide with bright color. By means of the method, vacuum sputtering time can be controlled to prepare the flaky iron oxide with various diameter-to-thickness ratios, and pollution caused by a traditional chemical deposition preparation method can be avoided. The preparation method is simple and environment-friendly. Due to the adoption of roller transmission, the production efficiency is improved.

The invention discloses a method for preparing a flaky iron oxide. The flaky iron oxide is obtained through a vacuum coating machine. The vacuum coating machine includes a vacuum pump, a vacuum pipeline arrangement, a vacuum coating chamber, a flaky iron oxide supporting chamber and an electrical discharging gas inlet. High-energy particles generated by an iron oxide target are deposited on the surface of the conveying belt; and then the flaky iron oxide on a conveying belt is stripped and calcined to obtain the flaky iron oxide with bright color. By means of the method, vacuum sputtering time can be controlled to prepare the flaky iron oxide with various diameter-to-thickness ratios, and pollution caused by a traditional chemical deposition preparation method can be avoided. The preparation method is simple and environment-friendly. Due to the adoption of roller transmission, the production efficiency is improved.

The present invention provides an electrocatalytic material and a method for making an electrocatalytic material. There is also provided an electrocatalytic material comprising amorphous metal or mixed metal oxides. There is also provided methods of forming an electrocatalyst, comprising an amorphous metal oxide film.

The present invention provides an electrocatalytic material and a method for making an electrocatalytic material. There is also provided an electrocatalytic material comprising amorphous metal or mixed metal oxides. There is also provided methods of forming an electrocatalyst, comprising an amorphous metal oxide film.

A radio wave absorber provided with a radio wave absorbing film formed on a substrate, the radio wave absorber being capable of absorbing radio waves over a broad frequency band and exhibiting superior radio wave absorbing properties even with a radio wave absorbing film thinner than 1 mm. A film forming paste suitable for forming a radio wave absorbing film that is provided in the radio wave absorber. In a radio wave absorber provided with a radio wave absorbing film formed on a substrate, a particular epsilon-type iron oxide is employed in the radio wave absorbing film and relative permittivity of the radio wave absorbing film is set to 6.5 to 65.

A radio wave absorber provided with a radio wave absorbing film formed on a substrate, the radio wave absorber being capable of absorbing radio waves over a broad frequency band and exhibiting superior radio wave absorbing properties even with a radio wave absorbing film thinner than 1 mm. A film forming paste suitable for forming a radio wave absorbing film that is provided in the radio wave absorber. In a radio wave absorber provided with a radio wave absorbing film formed on a substrate, a particular epsilon-type iron oxide is employed in the radio wave absorbing film and relative permittivity of the radio wave absorbing film is set to 6.5 to 65.

The present invention relates to an improved process for producing iron oxide red pigments by the Penniman process using nitrate (also referred to as nitrate process or direct red process).

The present invention relates to an improved process for producing iron oxide red pigments by the Penniman process using nitrate (also referred to as nitrate process or direct red process).

The object of the present invention is to provide a composition for a laminated coating film having designability to a coated body and weather resistance. The present invention provides a composition for a laminated coating film, comprising silicon oxide-coated iron oxide particles, wherein at least a part of the surface of said iron oxide particles is coated with silicon oxide, wherein the diameter of said iron oxide particles is 1 to 50 nm, and wherein the average reflectivity of said silicon oxide-coated iron oxide particles for the light of the wavelengths of 620 to 750 nm is 25% or less. It is preferable that the transmittance of the dispersion comprising said silicon oxide-coated iron oxide particles for the light of the wavelength of 200 to 420 nm is 2.0% or less, and the transmittance of the same for the light of the wavelength of 620 to 780 nm is 80% or more.

An e-type iron-based oxide magnetic particle powder has narrow particle size distribution and has a low content of fine particles which do not contribute to magnetic recording characteristics. As a result, a narrow coercive force distribution is achieved and the powder is suitable for increasing recording density of a magnetic recording medium. The powder containing substituting metal elements can be obtained by: adding an alkali to an aqueous solution containing trivalent iron ions and ions of the metals for partially substituting Fe sites to neutralize the aqueous solution to a pH of 1.5 to 2.5; then adding a hydroxycarboxylic acid; further adding the alkali to neutralize the aqueous solution to a pH of 8.0 to 9.0; washing with water a precipitation of an iron oxyhydroxide containing the substituting metal elements produced; and coating the iron oxyhydroxide containing the substituting metal elements with a silicon oxide and heating the resultant.