Titanium oxide, conductive titanium oxide, and processes for producing these

Patent metadata

Field	Value
Publication number	US-2016376160-A1
Application number	US-201615219653-A
Country	US
Kind code	A1
Filing date	Jul 26, 2016
Priority date	Mar 7, 2006
Publication date	Dec 29, 2016
Grant date	—

Abstract

Titanium dioxide and an electro-conductive titanium oxide which each includes particles having a large major-axis length in a large proportion and comprises columnar particles having a satisfactory particle size distribution. A titanium compound, an alkali metal compound, and an oxyphosphorus compound are heated/fired in the presence of titanium dioxide nucleus crystals having an aspect ratio of 2 or higher to grow the titanium dioxide nucleus crystals. Subsequently, a titanium compound, an alkali metal compound, and an oxyphosphorus compound are further added and heated/fired in the presence of the grown titanium dioxide nucleus crystals. Thus, titanium dioxide is produced which comprises columnar particles having a weight-average major-axis length of 7.0-15.0 μm and in which particles having a major-axis length of 10 μm or longer account for 15 wt. % or more of all the particles. A solution of a tin compound and a solution of compounds of antimony, phosphorus, etc. are added to a suspension obtained by suspending the titanium dioxide. The particles are sedimented. Subsequently, the product obtained is heated/fired to produce an electro-conductive titanium oxide which comprises the titanium dioxide and an electro-conductive coating formed on the surface thereof.

First claim

1 . Titanium dioxide in the shape of columnar particles having a weight-average major-axis length of 7.0-15.0 μm and including particles having a major-axis length of 10 μm or larger in a proportion of 15% by weight or more, and having a specific surface area of 1.0-3.5 m 2 /g.

2 . Titanium dioxide according to claim 1 , wherein the particles having a major-axis length of smaller than 5.0 μm are included in a proportion of 40% by weight or less, and having a specific surface area of 1.0-3.5 m 2 /g.

3 . Titanium dioxide according to claim 1 , wherein the weight-average minor-axis length of the particles is in the range of 0.25-1.0 μm.

4 - 11 . (canceled)

12 . A process for producing titanium dioxide which comprises heating and firing a titanium compound, an alkali metal compound and an oxyphosphorus compound in the presence of titanium dioxide nucleus crystals having an aspect ratio of 2 or higher and a weight-average major-axis length of 3.0-7.0 μm, thereby producing titanium dioxide in the shape of columnar particles having a weight-average major-axis length of 7.0-15.0 μm and including particles having a major-axis length of 10 μm or larger in a proportion of 15% by weight or more, and having a specific surface area of 1.0-3.5 m 2 /g.

13 - 23 . (canceled)

Assignees

• Ishihara Sangyo Kaisha

Inventors

• Isobe Kaoru
• Chiba Katsuichi
• Sakamoto Takanori

Classifications

• C01P2006/12

  Surface area · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2004/30

  extending in three dimensions · CPC title

• C01G23/047 Primary

  Titanium dioxide · CPC title