JPH0335064A - Production of titanyl phthalocyanine by crystallization - Google Patents

Abstract

PURPOSE:To obtain the title crystalline titanyl phthalocyanine which is useful in electrophotographic receptor by treating amorphous titanyl phthalocyanine with a specific organic solvent in the presence of water. CONSTITUTION:(A) Amorphous titanyl phthalocyanine is treated with (B) an aliphatic organic solvent of 8 to 11 solubility parameter such as cyclohexanone, or dichloroethane to convert the crystal structure into the one having peaks of X-rays diffraction spectrum to Cu-Kalpha line at 9.50+ or -0.2 deg., 24.1+ or -2 deg. and 27.2+ or -0.2 thereby the subject titanyl phthalocyanine is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for converting the crystal structure of titanyl phthalocyanine into a specific useful form.

[Prior art]

As electrophotographic photoreceptors, selenium, I lead oxide,
A photosensitive layer containing an inorganic photoconductive substance such as cadmium sulfide as a main component is provided; inorganic photoreceptors have been widely used; Cadmium sulfide has poor moisture resistance and durability, and zinc oxide also has poor moisture resistance and durability.
However, in recent years, organic photoconductive materials, which have various advantages, have been widely used in electrophotographic photoreceptors due to problems such as poor durability. Among them, phthalocyanine compounds have high photoelectric conversion quantum efficiency and exhibit high spectral sensitivity up to the near-infrared region, so they have attracted attention, especially as electrophotographic photoreceptors compatible with semiconductor laser light sources.

For such purposes, copper 7 talocyanine, metal-free 7
Electrophotographic photoreceptors using talocyanine, chlorindium 7-thalocyanine, chlorgallium phthalocyanine, etc. have been reported, but in recent years, titanyl 7-thalocyanine has attracted particular attention.
No. 48, No. 62-670943, No. 62-27227
2 and No. 63-116158, many electrophotographic photoreceptors using various crystal forms of titanyl phthalocyanine have been disclosed.

[Problem that the invention seeks to solve]

Generally, when a 7-thalocyanine compound is used in an electrophotographic photoreceptor, the properties thereof vary significantly depending on its crystalline state, so controlling the crystalline state is an important technique. For this reason, various crystal forms of titanyl phthalocyanine have been developed as seen in the above-mentioned publications. However, the characteristics of an electrophotographic photoreceptor vary significantly depending on the crystal type and also depending on the manufacturing conditions, so a crystal type with high sensitivity and excellent charging ability is required for titanyl phthalocyanine for electrophotographic photoreceptors. At the same time, it is necessary that it can be produced in a stable state. Under such circumstances, the X-ray diffraction spectra for the Cu-Ka line were 9.5±0.2@, 24.1±0.2°, 27.2±
It has been found that particularly remarkable sensitivity is achieved in a crystalline state with a peak at 0.2". However, this particular crystalline state cannot be stably produced by conventional solvent treatment or milling. There wasn't.

[Purpose of the invention]

The object of the present invention is to provide CB-Ka, which is useful for electrophotographic photoreceptors.
9.5±0.2m of the X-ray diffraction spectrum for the line, 2
The object of the present invention is to provide a method for producing titanyl phthalocyanine having a crystalline state showing peaks at 4.1±0.2° and 27.2±0.2°.

[Structure and effects of the invention]

The production method targeted by the present invention involves converting titanyl-7 thalocyanine into an amorphous state or other thermally non-equilibrium crystalline state, and then changing the solubility parameter value from 8 to 8 in the presence of water.
The treatment is carried out with an aliphatic organic solvent falling within the range of No. 11.

Titanyl 7-lycyanine is represented by the following general formula, where xi xM xl X4 represents a hydrogen atom, a halogen atom, an alkyl group, or an alkoxy group, and n,
m, (1, represents an integer from 0 to 4.

The X-ray diffraction spectrum is measured under the following conditions, and the peak here is an acute-angled pyramidal projection that is clearly different from noise.

X-ray tube Cu voltage 40.0 kV
Current 100 mA
Starting angle 6. Odeg.

Stop angle 35. Odog.

Step angle 0.02 dos.

Measurement time 0.50 sec.

In the present invention, the amorphous state is a state in which the peak is generally broad or no peak is observed in the X-ray diffraction spectrum, and for example, titanyl-7 talocyanine is dissolved in sulfuric acid and then poured into water to precipitate. You can get it by doing this. This method is called acid paste treatment, and the amorphous titanyl-7-talocyanine obtained by acid paste treatment generally has a peak in the 6-8° region of the X-ray diffraction spectrum.

The amount of water used can be selected within a wide range. The concentration of water in the immediate vicinity of titanyl-7-thalocyanine is important, so when using wet paste immediately after acid paste treatment, the surface of titanyl-7-thalocyanine is moistened with water, so A very small amount of water is sufficient.

Aliphatic organic solvents can be classified by solubility parameters,
If the solubility parameter is too large, a crystalline state other than the desired crystalline type will preferentially be produced during crystal growth of titanyl-7-talocyanine, making it impossible to stably obtain the desired crystalline state. Furthermore, if a solvent has a too small solubility parameter, the affinity for titanyl phthalocyanine will be too low, and the ability to create a crystal arrangement will be insufficient, making it impossible to sufficiently grow the desired crystal.

In the production method of the present invention, the solubility parameter is 8 to 11.
A solvent within the range of is used. Examples of solvents in this range include ketones such as cyclohexanone, methyl ethyl ketone, and methyl t-butyl ketone, ethers such as tetrahydro7rane, dioxane, and diimbutyl ether, dichloromethane, chloroform, carbon tetrachloride, and 1,2- Halogenated hydrocarbons such as dichloroethane, 1.1.2-trichloroethane, 1.1.2.2-tetrachloroethane, bromogloban, 1.1.24-lichlorethylene, ethyl acetate, isopropyl acetate, vinegar fi
Examples include esters such as -t-butyl and methyl propionate, and long chain alcohols such as cyclohexanol and pentanol.

The processing method is to stir with a general stirring device, but it is also possible to use mechanical force using a homomixer, disperser, agitator, ball mill, sand mill, attritor, ultrasonic dispersion device, etc. .

The titanyl phthalocyanine thus obtained exhibits particularly excellent properties when used as a carrier generating material for electrophotographic photoreceptors. In such applications, titanyl phthalocyanine is first dispersed in a suitable solvent using a sand mill, ball mill, etc., and coated on a conductive support to form a carrier generation layer, and a carrier transport material is applied on top of this. An electrophotographic photoreceptor can be produced by coating a solution obtained by dissolving the above and a binder in a solvent to form a carrier transport layer.

Next, the specifics of the present invention! l! An example is shown.

〔Example〕

(Synthetic leather of titanyl 7 thalocyanine) 1.3-diiminoinindoline: 29.2g and α-
Mix 20Gm+2 of chlornaphthalene, add 20.4g of titanium tetrabutoxide, heat at 140-150°C for 2 hours under nitrogen atmosphere, and heat to 180°C.
The reaction was carried out at ℃ for 3 hours. After cooling, the precipitate was collected by filtration, a.
- Washing with chlornaphthalene, then washing with chloroform, further washing with 2% aqueous hydrochloric acid, washing with water, and finally washing with methanol to obtain 26.2 g (91.0%) of titanyl 7-talocyanine after drying.

(Example 1) Titanyl phthalocyanine; 100 g was dissolved in 2 kg of concentrated sulfuric acid, poured into 2,012 ml of water, precipitated and collected by filtration to obtain an amorphous wet paste.

Further, a part of this wet paste was dried to obtain an amorphous dry powder. The X-ray diffraction spectrum of the dry powder is shown in FIG.

Amorphous wet paste; 1.2- to 2g
Dichloroethane; Add 200ml and leave at room temperature 2
Stir for hours. Thereafter, the mixture was diluted with 400 mg of methanol, filtered, washed with methanol, and dried to obtain crystals having the X-ray diffraction pattern shown in FIG.

<*Example 2)! lI Add 200·a of nat-2-hydrofuran to 2 g of the amorphous wet paste used in Example 1,
Stirring was performed for 1 hour while cooling with water. The mixture was diluted with methanol, filtered, washed with methanol, and dried to obtain crystals having the X-ray diffraction pattern shown in FIG.

(Example 3) 1.1 g of the amorphous dry powder obtained in Example 1
．． 2.2-tetrachloroethane; add 100-a,
Water; 100 mff1 was added dropwise with stirring, and then 3 at 50°C.
Stir for hours. After cooling, dilute with methanol; 400ml, filter, wash with methanol, dry, and
A crystal with a line diffraction pattern was obtained.

(Application example) Titanyl 7 thalocyanine shown in Figure 1 obtained in Example 1: 2 g
and silicone resin rKR-5240, 15% xylene-
Disperse 30 g of "butanol solution" (manufactured by Shin-Etsu Chemical Co., Ltd.) in a 100 m2 inklorol solution using a sand mill, and apply this onto a polyester base coated with aluminum using a wire bar to form a carrier generation layer with a thickness of 0.3 mm. was formed. Next, 1.2 g of N,N-diethylamino-p-benzaldehyde diphenylhydrazone as a carrier transport substance and a polycarbonate resin "Nipilon Z-200J (manufactured by Mitsubishi Gas Chemical Co., Ltd.)" were added thereon.
;1.5g and 1,2-dichloroethane; 10m+1
A carrier transport layer having a thickness of 20 μm was formed by applying a solution dissolved in the above using a blade coating machine, and an electrophotographic photoreceptor was prepared.
.

The photoreceptor thus obtained was processed using a paper analyzer E.
The following evaluation was performed using PA-8100 (manufactured by Kawaguchi Electric Co., Ltd.). That is, the surface is negatively corona charged to approximately 1200V, the potential decay rate is determined for 5 seconds, and the surface is exposed to light such that the surface illuminance is 2 (lux). The exposure amount E 1/1 required to reduce the value to 1/2 was determined.

The result was D-21% and E I/! −0,7(1
(ux-sec), and exhibited excellent characteristics in both charging ability and sensitivity.

[Brief explanation of drawings]

FIG. 1 is an X-ray diffraction diagram of titanyl phthalocyanine in an amorphous state, and FIGS. 2 to 4 are X-ray diffraction diagrams of titanyl 7-thalocyanine according to the present invention.

Claims (1)

[Claims] By treating amorphous titanyl phthalocyanine with an aliphatic organic solvent having a solubility parameter value in the range of 8 to 11 in the presence of water, the X-ray diffraction spectrum for the Cu-Ka line was 9.5±0.2.゜、24.1±0
．． A method for producing titanyl phthalocyanine, which comprises converting the titanyl phthalocyanine into a crystalline state exhibiting peaks at 2° and 27.2±0.2°.