Making method for titania nanoparticle

• US 8,178,073 B2
• Filed: 09/04/2009
• Issued: 05/15/2012
• Est. Priority Date: 09/05/2008
• Status: Active Grant

• Current Assignee: Sukgyung AT Co., Ltd.
• Original Assignee: Sukgyung AT Co., Ltd.
• Inventors: Lim, Hyung Sup, Lim, Hyung Joon, Yoo, Young Cheol, Kwon, Osung
• Primary Examiner(s): BOS, STEVEN J
• Application Number:
  US12/554,558
• Publication Number:
  US 20110189605A1
• Time in Patent Office: 984 Days
• Field of Search: 423610-616, 423 80- 86
• US Class Current: 423/610
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01G 23/047 Titanium dioxide
• CPC Class Codes: C01G 23/053 Producing by wet processes, e.g. hydrolysing titanium salts
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

The present invention relates to a method of manufacturing titania nanoparticles, and specifically to a method of manufacturing titania nanoparticles wherein the particle size is uniform, it is possible to manufacture monodisperse particles without aggregation among particles, a uniform coating can be applied, that is suitable to large-scale production, and that can obtain high-resolution images by maintaining the toner electric charge and electric charge distribution; and the developer included in said titania nanoparticles.

Claims

1. A method of manufacturing titania nanoparticles, comprising:

(1) a step wherein a salt or alkoxide of titania is mixed with a solvent and scanned with microwaves to synthesize a titania precursor;

(2) a step wherein an alkaline catalyst is added to the solvent and the titania precursor obtained in step (1) to produce spherical nanoparticles of titanium hydroxide;

(3) a step wherein crystalline spherical titania particles are made by-drying and sintering the titanium hydroxide; and

(4) a step wherein the crystalline spherical titania particles obtained in step (3) are hydrophobized.

2. The method of manufacturing titania nanoparticles of claim 1, wherein the titania salt or titania alkoxide of step (1) comprises one or more titania salt or titania alkoxide selected from the group consisting of titanium oxychloride, titanium chloride, titanium nitrate, titanium sulfate, and C1-C12 titanium alkoxides.

3. The method of manufacturing titania nanoparticles of claim 1, wherein the alkaline catalyst is a compound containing an amine group, hydroxy group, or an aqueous solution of an amine group or hydroxy group.

4. The method of manufacturing titania nanoparticles of claim 1, wherein the alkaline catalyst is added so that the pH of the combined salt or alkoxide of titania and solvent is between 5 and 10 after the addition of the catalyst.

5. The method of manufacturing titania nanoparticles of claim 1, wherein the drying takes place over 4 to 12 hours at 100-130°

C. after preparatory drying at 50-70°

C. over 1 to 3 hours.

6. The method of manufacturing titania nanoparticles of claim 1, wherein the sintering takes place over 1 to 4 hours at 600-800°

C.

7. The method of manufacturing titania nanoparticles of claim 1, wherein the hydrophobization of step (4) is performed with one or more hydrophobization agents selected from the group consisting of hexamethyldisilazane, methyltrimethoxysilane, dimethyldiethoxysilane, and trimethylethoxysilane, isopropyl triisostearoyl titanate, isopropyl dimethaacryl isostearoyl titanate, isopropyl tri(dodecyl)benzenesulfonyl titanate, isopropyl tri(dioctyl)pyrophosphato titanate, di(cumyl)phenyl oxoethylene titanate, di(dioctyl)pyrophosphate oxoethylene titanate, neopentyl(diallyl)oxy, and tri(dioctyl)pyro-phosphato titanate.

8. The method of manufacturing titania nanoparticles of claim 7, wherein the hydrophobization agent is used at 1 to 20 weight parts with respect to 100 weight parts of crystalline titania nanoparticles, relative to the solid component.