Patents by Inventor Motohide Wada

Motohide Wada 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).

  • Process for producing silica particles suitable for use as filler for paper
    Patent number: 6685907
    Abstract: The present invention relates to a process for easily and efficiently producing silica particles having a narrow particle size distribution and a high porosity from inexpensive starting materials such as sodium silicate. The silica particles of the present invention can be obtained in the form of a slurry containing them by (1) forming a slurry by mixing first particles difficultly soluble in an alkali and soluble in an acid, with an aqueous alkali silicate solution to form a first slurry containing the first particles, (2) neutralizing the first slurry with a mineral acid to prepare a second slurry containing second particles wherein silica is deposited on the first particles, and (3) adding a mineral acid to the second slurry to dissolve the first particles from the second particles, to prepare a third slurry containing silica particles.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: February 3, 2004
    Assignee: Oji Paper Co., Ltd.
    Inventors: Masashi Matsuda, Masasuke Watanabe, Hitoshi Okada, Motohide Wada, Osamu Kitao
  • Process for producing silica particles suitable for use as filler for paper
    Patent number: 6413373
    Abstract: The present invention relates to a process for easily and efficiently producing silica particles having a narrow particle size distribution and a high porosity from inexpensive starting materials such as sodium silicate. The silica particles of the present invention can be obtained in the form of a slurry containing them by (1) forming a slurry by mixing first particles difficultly soluble in an alkali and soluble in an acid, with an aqueous alkali silicate solution to form a first slurry containing the first particles, (2) neutralizing the first slurry with a mineral acid to prepare a second slurry containing second particles wherein silica is deposited on the first particles, and (3) adding a mineral acid to the second slurry to dissolve the first particles from the second particles, to prepare a third slurry containing silica particles.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: July 2, 2002
    Assignee: OJI Paper Co., Ltd.
    Inventors: Masashi Matsuda, Masasuke Watanabe, Hitoshi Okada, Motohide Wada, Osamu Kitao
  • Process for producing silica particles suitable for use as filler for paper
    Publication number: 20020040773
    Abstract: The present invention relates to a process for easily and efficiently producing silica particles having a narrow particle size distribution and a high porosity from inexpensive starting materials such as sodium silicate. The silica particles of the present invention can be obtained in the form of a slurry containing them by (1) forming a slurry by mixing first particles difficultly soluble in an alkali and soluble in an acid, with an aqueous alkali silicate solution to form a first slurry containing the first particles, (2) neutralizing the first slurry with a mineral acid to prepare a second slurry containing second particles wherein silica is deposited on the first particles, and (3) adding a mineral acid to the second slurry to dissolve the first particles from the second particles, to prepare a third slurry containing silica particles.
    Type: Application
    Filed: April 12, 2001
    Publication date: April 11, 2002
    Applicant: Oji Paper Co., Ltd.
    Inventors: Masashi Matsuda, Masasuke Watanabe, Hitoshi Okada, Motohide Wada, Osamu Kitao
  • Process for producing silica particles suitable for use as filler for paper
    Publication number: 20010018038
    Abstract: The present invention relates to a process for easily and efficiently producing silica particles having a narrow particle size distribution and a high porosity from inexpensive starting materials such as sodium silicate. The silica particles of the present invention can be obtained in the form of a slurry containing them by (1) forming a slurry by mixing first particles difficultly soluble in an alkali and soluble in an acid, with an aqueous alkali silicate solution to form a first slurry containing the first particles, (2) neutralizing the first slurry with a mineral acid to prepare a second slurry containing second particles wherein silica is deposited on the first particles, and (3) adding a mineral acid to the second slurry to dissolve the first particles from the second particles, to prepare a third slurry containing silica particles.
    Type: Application
    Filed: April 12, 2001
    Publication date: August 30, 2001
    Applicant: Oji Paper Co., Ltd.
    Inventors: Masashi Matsuda, Masasuke Watanabe, Hitoshi Okada, Motohide Wada, Osamu Kitao
  • Process for producing silica particles suitable for use as filler for paper
    Patent number: 6264907
    Abstract: The present invention relates to a process for easily and efficiently producing silica particles having a narrow particle size distribution and a high porosity from inexpensive starting materials such as sodium silicate. The silica particles of the present invention can be obtained in the form of a slurry containing them by (1) forming a slurry by mixing first particles difficultly soluble in an alkali and soluble in an acid, with an aqueous alkali silicate solution to form a first slurry containing the first particles, (2) neutralizing the first slurry with a mineral acid to prepare a second slurry containing second particles wherein silica is deposited on the first particles, and (3) adding a mineral acid to the second slurry to dissolve the first particles from the second particles, to prepare a third slurry containing silica particles.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: July 24, 2001
    Assignee: OJI Paper Co., Ltd.
    Inventors: Masashi Matsuda, Masasuke Watanabe, Hitoshi Okada, Motohide Wada, Osamu Kitao