Method for preparing coloring layer composition for chromatic device

• US 5,961,891 A
• Filed: 07/24/1998
• Issued: 10/05/1999
• Est. Priority Date: 07/24/1997
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Original Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Inventors: Komori, Takashi, Kato, Yoshifumi, Murasaki, Takanori, Inoue, Toshiki
• Primary Examiner(s): WU, SHEAN CHIU
• Application Number:
  US09/122,357
• Time in Patent Office: 438 Days
• Field of Search: 423/606, 423/62, 427/126.3, 252/586, 252/301.5, 252/186.41, 252/583, 252/582, 428/469, 428/472, 359/265, 359/270, 359/273
• US Class Current: 252/582
• CPC Class Codes: C09K 9/00 Tenebrescent materials, i.e. materials for which the range of wavelengths for energy absorption is changed as a result of excitation by some form of energy
• CPC Class Codes: G02F 1/1524 Transition metal compounds

Abstract

The present invention relates to a method for preparing a coloring layer composition for a chromatic device comprising a step of preparing a peroxotungstic acid solution comprising a solute including WO₃ aNb₂ O₅ bH₂ O₂ cH₂ O (a, b, and c represent a positive number), water for dispersing and holding the solute, and an organic solvent compatible with water, and aging the peroxotungstic acid solution to obtain a polymer. According to the method of the present invention, a large size chromatic device can be reliably produced at a low cost. Further, a composition having a sufficient coloring effect and a quick response speed of the coloration-bleaching change in the chromatic device can be prepared.

Claims

1. A method for preparing a coloring layer composition for a chromatic device comprising a step of preparing a peroxotungstic acid solution comprising a solute including WO₃ 

aNb₂ O₅ 

bH₂ O₂ 

cH₂ O (a, b, and c represent a positive number), water for dispersing and holding the solute, and an organic solvent compatible with water, and aging the peroxotungstic acid solution to obtain a polymer.

2. The method according to claim 1, comprising:

a first step of obtaining a first solution by dissolving W powders and NbC powders in H₂ O₂ ;

a second step of obtaining a second solution by separating C from the first solution;

a third step of obtaining a third solution containing WO₃ 

aNb₂ O₅ 

bH₂ O₂ 

cH₂ O (a, b, and c represent a positive number) by decomposing excessive H₂ O₂ and evaporating excessive water from the second solution; and

a fourth step of adding an organic solvent to the third solution.

3. The method according to claim 1, wherein the organic solvent is selected from alcohols having C₁ to C₆ carbon atoms.

4. The method according to claim 3, wherein the alcohol is propanol.

5. The method according to claim 1, wherein the ratio of the solute :

water ;

organic solvent is, 1 ;

about 0.1 to 5 ;

about 0.4 to 20.

6. The method according to claim 1, wherein the aging operation is conducted at a temperature of from about 20°

C. to 80°

C.