JPS6052090B2 - white conductive coated powder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a white conductive coating powder which has good conductivity and is particularly suitable for use in forming a conductive layer on copy paper such as electrostatic recording paper.

In general, to form a conductive layer in electrostatic recording paper, for example, it is necessary to use a white inorganic electrolyte powder such as ammonium sulfate, since the conductivity may be lower than that of electrically conductive thermal paper, that is, it may have higher resistance. Alternatively, organic electrolyte powders are used, but these white electrolyte powders have the property of adsorbing moisture in the air or paper, so this adsorbed moisture changes the resistance of the conductive layer. At present, it is extremely difficult to impart stable conductivity to the conductive layer of electrostatic recording paper. Therefore, from the above-mentioned viewpoints, the present inventors have developed a material that exhibits white color, stably has good conductivity, and is suitable for use in forming a conductive layer on copying paper such as electrostatic recording paper. As a result of research to obtain titanium oxide powder at a low cost, we found that titanium oxide (hereinafter referred to as TI
O. Copper chloride (hereinafter referred to as SbCl3) and antimony chloride (hereinafter referred to as SbCl) are dissolved in alcohol, hydrochloric acid, or acetone in a heated suspension consisting of a powder (denoted as ) dispersed in heated water. When a solution consisting of TiO is added, tin oxide (hereinafter referred to as sno2) in which antimony (Sb) is uniformly dissolved becomes the TiO. The Sb-containing SnO precipitates on the surface of the powder. T.I.O. The precipitation on the powder surface is the TIO described above. SnO containing SnO is significantly promoted by the activity of SnO. is deposited in a uniform layer thickness, and the resulting coated powder is pure white and has no hygroscopicity, and can be used, for example, to form a conductive layer in electrostatic recording paper. They found that it has a specific resistance of 1 to 1 MΩ-α and is extremely stable in terms of quality. The present invention was made based on the above findings, and includes a titanium oxide powder having a specific surface area of 1 to 10 i/g with Sb: 1 to 15% by weight (hereinafter all % means weight%). ), and the remainder is substantially s
The coating layer consisting of no2 is 0.001 to 0.007 μm.
It is characterized by a white conductive coating powder formed with a layer thickness of less than

Next, the reason why the specific surface area, Sb content, and layer thickness are limited as described above in the white conductive coating powder of the present invention will be explained.

(a) TiO.

Powder specific surface area If the specific surface area is less than ld/g, the TI
O.

As the particle size of the powder itself becomes coarser, for example, when it is used to form a conductive layer on electrostatic recording paper, the paper surface loses its smoothness.On the other hand, if the specific surface area becomes too fine, exceeding 10d/g, During its manufacture, TiO. As the cohesive force of the powder becomes strong, it becomes difficult to disperse it uniformly in heated water, and as a result, it becomes impossible to produce a homogeneous coated powder, so the specific surface area was set at 1 to 10 I/g. .
(b) Implicit S content in the coating layer If the content is less than 1%, it is not possible to ensure conductivity with a specific resistance of 1 MΩ-G or less in relation to the layer thickness.
On the other hand, if the content exceeds 15%, the white color will be lost and the color will become blueish, so the content should be between 1 and 15%.
It was determined that

(c) Thickness of coating layer If the layer thickness is less than 0.001 μm, it is possible to ensure conductivity of specific resistance: 1 MΩ-0 or less in relation to the Sb content.On the other hand, for example, conductivity in electrostatic recording paper Minimum specific resistance required for layer formation: 1KΩ-0 is 0.007
The layer thickness was determined to be less than 0.001 to 0.007 μm since a sufficiently satisfactory layer thickness of Ωm could be obtained.

Next, the white conductive coating powder of the present invention will be explained with reference to Examples.

Example 1 TlO2 powder with specific surface area of 57T1/g: 100
0g of water was added to 700C, heated and maintained at a temperature of 90C, and while stirring, a solution consisting of 150g of SnCf4 and 20g of Sbce3 dissolved in 500CC of ethanol was slowly injected over 2 hours. Then, a coating layer made of Sb-containing SnO2 was deposited on the surface of the TlO2 powder, which was then filtered, washed, and kept in air at a temperature of 500°C for 2 hours to improve crystallinity. The coated powder of the present invention was produced by heat treatment.

The resulting coated powder of the present invention has a white coating layer containing 10% Sb, with the remainder substantially consisting of SnO2, and having a uniform layer thickness of 0.003 pm, Moreover, it had a specific resistance of 1.5KΩ-α.

Example 2 TiO2 powder with specific surface area of 7 Wt/g: 1000
Add 10,001 g of methanol to 7,000 cc of water, maintain the temperature at 90°C, and add 10,001 cc of methanol while stirring.
1) Snce4:250g and SbC'3:1 to C
A solution consisting of 7 g dissolved therein was slowly added dropwise over a period of 3 hours, and thereafter the coated powder of the present invention was produced using the same operations and conditions as in Example 1.

The resulting coated powder of the present invention contains 6% Sb, with the remainder substantially consisting of SnO2, and has a white coating layer with a uniform layer thickness of 0.003 μm, Moreover, it had a specific resistance of ice Ω-0.

Example 3 Injection solution? Hydrochloric acid aqueous solution: 400CC and SnCl4:
The coated powder of the present invention was produced under the same conditions as in Example 1 except that 100 g and 17 g of Sbce3 were dissolved.

The resulting coated powder of the present invention has a specific resistance of IOKΩ-o, a composition consisting of Sb: 13%, SrlO2: the remainder, and a white coating layer with a uniform layer thickness of 0.002 μm. It was something I had.

Example 4 SnC'4 in acetone 400CC as injection solution
An example coated powder was produced under the same conditions as in Example 1 except that 75 g of SbCf3 and 12.5 g of SbCf3 were used.

The coated powder of the present invention obtained as a result has a specific resistance of 100KΩ-a, and the composition of the coating layer is Sb: 13%,
SnO2: consists of the remainder, and the layer thickness of the coating layer is 0.00
It had a white color with a diameter of 15 μm.

Claims (1)

[Claims] 1 Containing antimony: 1 to 15% by weight on the surface of titanium oxide powder having a specific surface area of 1 to 10 m^2/g,
The remainder of the coating layer consists essentially of tin oxide, with a coating layer of 0.001 to
A white conductive coating layer powder formed with a layer thickness of less than 0.007 μm.