Making Method for Titania Nanoparticle

• US 20110189605A1
• Filed: 09/04/2009
• Published: 08/04/2011
• Est. Priority Date: 09/05/2008
• Status: Active Grant

• Current Assignee: Sukgyung AT Co., Ltd.
• Original Assignee: Sukgyung AT Co., Ltd.
• Inventors: Kwon, Osung, Lim, Hyung Joon, Yoo, Young Cheol, Lim, Hyung Sup
• Granted Patent: US 8,178,073 B2
• Time in Patent Office: Days
• US Class Current: 430/108.6
• 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 stage wherein a salt or alkoxide of titania is mixed with a solvent and scanned with microwaves to synthesize a titania precursor;

(2) a stage wherein an alkaline catalyst is added to the solvent containing titania precursor obtained in stage (1) above, so as to produce spherical nanoparticles of titanium hydroxide;

(3) a stage wherein crystalline spherical titania particles are made through stages of drying and sintering the titanium hydroxide obtained in step (2) above; and

(4) a stage wherein the nanoparticles obtained in step (3) above are hydrophobized.

2. The method of manufacturing titania nanoparticles of claim 1, wherein the titania salt or titania alkoxide of step (1) comprises 1 or more selected from among the group comprising 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 of step (2) above is a compound containing an amine or hydroxy group, or an aqueous solution of same.

4. The method of manufacturing titania nanoparticles of claim 1, wherein the aforementioned alkaline catalyst of step (2) is added so that the pH of the mixture is between 5 and 10 after the addition of the catalyst.

5. The method of manufacturing titania nanoparticles of claim 1, wherein the aforementioned drying of step (3) 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 aforementioned sintering of step (3) takes place over 1 to 4 hours at 600-800°

C.

7. The method of manufacturing titania nanoparticles of claim 1, wherein the aforementioned hydrophobization of step (4) is performed using one or more hydrophobization agents chosen from among the group comprising hexamethyldisilazane (HMDS), methyltrimethoxysilane (MTMS), dimethyldiethoxysilane (DMDES), and trimethylethoxysilane (TMES), isopropyl triisostearoyl titanate (KR-TTS), isopropyl dimethaacryl isostearoyl titanate (KR-7), isopropyl tri(dodecyl)benzenesulfonyl titanate (KR-9S), isopropyl tri(dioctyl)pyrophosphato titanate (KR-38S), di(cumyl)phenyl oxoethylene titanate (KR-134S), di(dioctyl)pyrophosphate oxoethylene titanate (KR-138S), neopentyl(diallyl)oxy, and tri(dioctyl)pyro-phosphato titanate (LICA-38).

8. The method of manufacturing titania nanoparticles of claim 7, wherein the aforementioned hydrophobization agent of step (4) is used at 1 to 20 weight parts with respect to 100 weight parts of crystalline titania nanoparticles (relative to the solid component).

9. Monodisperse spherical titania nanoparticles, wherein an average diameter of said titania nanoparticles is between 30 and 200 nm, a specific surface area is between 20 and 100 m2/g.

11. The titania nanoparticles of claim 9, wherein said titania nanoparticles have a contact angle with respect to water of between 100 and 170°

.

12. The titania nanoparticles of claim 9, wherein said titania nanoparticles are an external toner additive for electrostatic development.

10. (canceled)

13. A developer comprising monodisperse spherical titania nanoparticles and toner particles.

14. The developer of claim 13, further comprising a carrier.

15. The developer of claim 13, wherein 0.01 to 20 weight parts of the aforementioned titania nanoparticles are included with respect to 100 weight parts of toner particles.

16. The developer of claim 13, wherein an average diameter of said titania nanoparticles is between 30 and 200 nm, a specific surface area is between 20 and 100 m2/g.

17. The developer of claim 13, wherein the monodisperse spherical titania nanoparticles have a contact angle with respect to water of between 100 and 170°

.

18. The developer of claim 13, wherein the monodisperse spherical titania nanoparticles are an external toner additive for electrostatic development.