Nippon Aerosil Co., Ltd.

Hodogaya Chemical Co., Ltd.

Nippon Aerosil Co., Ltd. (Nac)

Yuki Amano

Hideyuki Otsuka

Hisao Okada

Masaki Okubo

Yoshikazu Aoki

Hirokuni Shirono

Takeyoshi Shibasaki

Naruyasu Ishibashi

Masamichi Murota

Naohiro Naito

Provided by the present invention is a surface-modified silica powder, characterized in that the said powder is obtained by surface treatment of a silica powder with one or two or more of a compound (A) and with an aminosilane (B), wherein the fixing rate of the compound (A) and the aminosilane (B) is a total of 50% or more, the hydrophobic rate is 80% or more, and the triboelectrostatic charge amount is 200 &#x3bc;C/g or less in its absolute value. The surface-modified silica powder of the present invention can stabilize many properties including fluidity and electrostatic properties while can significantly reduce problems such as fogging and decrease in image quality without significantly deteriorating characteristics of a developing agent and so forth when this is used as an external additive.

Surface-modified silica powder and method for producing the same, as well as toner composition for electrophotography

A surface modified inorganic oxide powder is provided, which includes inorganic oxide particles having a surface modified with a mixed solution, which includes an organopoly-siloxane and a silane compound, in the presence of an acid or a base.

Surface-modified inorganic oxide powder, process for producing the same, and use thereof

A surface modified fine silica powder which has been treated, preferably, with a treating agent containing an amino group, characterized in that the powder exhibits an adsorption amount for an anion source compound of 150% or more of that of an original powder which has not been treated; and a printing material using the silica powder. The surface modified fine silica powder can provide an excellent printed matter being free from blotting with ink or a cracking of coating film.

Surface-modified fine silica powder and use thereof

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Yokkaichi, Japan

Yuki Amano