CN111471051A

CN111471051A - Phthalocyanine eutectic crystal and preparation method and application thereof

Info

Publication number: CN111471051A
Application number: CN202010360104.9A
Authority: CN
Inventors: 谢锦楼; 林日彬
Original assignee: Guangzhou Anguo Technology Co ltd
Current assignee: Guangzhou Anguo Technology Co ltd
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2020-07-31
Anticipated expiration: 2040-04-29
Also published as: CN111471051B

Abstract

The invention discloses a phthalocyanine eutectic crystal and a preparation method and application thereof. The phthalocyanine eutectic is formed by oxytitanium phthalocyanine and phthalocyanine without metal, wherein the weight ratio of the oxytitanium phthalocyanine to the phthalocyanine without metal is 99:1-1: 99. The phthalocyanine eutectic has higher sensitivity, can be used as a photogenerating material for preparing a charge generating layer of an electrophotographic imaging element, and the sensitivity of the electrophotographic imaging element can be continuously adjusted according to the weight ratio of oxytitanium phthalocyanine to phthalocyanine without metal in the phthalocyanine eutectic.

Description

Phthalocyanine eutectic crystal and preparation method and application thereof

Technical Field

The invention relates to the technical field of electrophotographic imaging devices, in particular to a phthalocyanine eutectic crystal and a preparation method and application thereof.

Background

In the field of electrophotography, an electrophotographic negative containing a conductive layer and a photoconductive insulating layer is first imaged by uniformly electrostatically charging the imaging surface of the photoconductive insulating layer; then exposing the negative to activating electromagnetic radiation that selectively dissipates the charge in the irradiated areas of the photoconductive insulating layer while leaving a latent electrostatic image in the non-irradiated areas; the resulting latent electrostatic image is developed to form a visible image by depositing finely divided electroscope toner particles on the surface of the photoconductive insulating layer, and the resulting visible image can be transferred to a suitable receiving member. This imaging process can be repeated many times with reusable electrophotographic imaging members.

The electrophotographic imaging member can be in the form of a negative, a rotating drum, or a flexible belt. These electrophotographic members are typically multilayer photoreceptors comprising a substrate, a conductive layer, an undercoat layer (hole blocking layer), an optional adhesive layer, a charge generating layer, a charge transport layer, and an optional protective layer, and in some flexible belt photoreceptors an anti-curl back layer. The charge generating layer of a multilayer photoreceptor typically comprises a polymer and either inorganic photoconductive particles or organic photoconductive particles uniformly dispersed in the polymer, and the inorganic or organic photoconductive material may be formed as a continuous uniform charge generating segment.

Sensitivity is a very important electrical property of an electrophotographic imaging member or photoreceptor. Sensitivity can be described in two ways: the first aspect is spectral sensitivity, which represents sensitivity as a function of wavelength, an increase in spectral sensitivity meaning the occurrence of sensitivity at wavelengths at which sensitivity was not previously detected; the second aspect is broadband sensitivity, which is a change in sensitivity at a specific wavelength at which sensitivity was previously displayed, or a general increase in sensitivity at wavelengths including all of the previously displayed sensitivity; the broadband sensitivity can also be described as including the change in sensitivity for all wavelengths with broadband (white) light exposure.

The sensitivity of an electrophotographic imaging member or photoreceptor is closely related to the choice of photogenerated material. Currently, common organic photogenerating materials in the field of electrophotography include pyrene, bisazo, perinone, polycyclic quinone, etc., and electrophotographic imaging elements containing such materials exhibit good photosensitivity in the visible region of the spectrum, and therefore, these organic photogenerating materials are particularly suitable for electrophotographic processes using visible light sources such as tungsten lamps, fluorescent lamps, and xenon lamps. However, these organic photogenerating materials have low photosensitivity in the near infrared region (750nm to 970nm), which prevents their use in photoresponsive imaging elements of laser printers. In addition, some of the organic photovoltaic materials described above have narrow and limited spectral response ranges, making them unable to reproduce some of the colors present in the original document, resulting in poor reproduction quality.

Oxytitanium phthalocyanine is a suitable photogenerating material currently known to absorb near-infrared light at about 800 nanometers, and has better sensitivity than other phthalocyanine materials, such as hydroxygallium phthalocyanine. Known oxytitanium phthalocyanines have crystal forms of forms I, II, III, X, IV, Y and V, among others. Various polymorphs of oxytitanium phthalocyanine have proven suitable materials in the charge generating or photogenerating layer of electrophotographic imaging members or devices. The oxytitanium phthalocyanines of different crystal forms generally have different sensitivities, but because the chemical components of the oxytitanium phthalocyanines are the same, the adjustable range of the sensitivities is very limited, and continuous adjustability cannot be realized. To meet the great demands of the modern high-speed xerographic/laser printing industry, electrophotographic imaging members with high sensitivity and continuously adjustable sensitivity are required in the market at present, and the oxytitanium phthalocyanine material is required to have adjustable crystal form and adjustable chemical composition.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a phthalocyanine eutectic, a preparation method and application thereof, wherein the sensitivity of the phthalocyanine eutectic can be continuously adjusted by changing the weight ratio of oxytitanium phthalocyanine to phthalocyanine without metal, and the phthalocyanine eutectic can be used as a photovoltaic material for preparing an electrophotographic imaging element.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a phthalocyanine eutectic is formed by oxytitanium phthalocyanine and phthalocyanine without metal, wherein the weight ratio of the oxytitanium phthalocyanine to the phthalocyanine without metal is 99:1-1: 99.

Compared with the prior oxytitanium phthalocyanine material, the phthalocyanine eutectic crystal has higher sensitivity, and the sensitivity can be continuously adjusted according to the weight ratio of the oxytitanium phthalocyanine to the phthalocyanine without metal.

Preferably, the weight ratio of the oxytitanium phthalocyanine to the metal-free phthalocyanine is from 95:5 to 50: 50.

The invention also provides a preparation method of the phthalocyanine eutectic crystal, which comprises the following steps:

(1) weighing oxytitanium phthalocyanine coarse crystals and phthalocyanine coarse crystals without metal according to a ratio;

(2) dissolving oxytitanium phthalocyanine crude crystals and metal-free phthalocyanine crude crystals in a solvent A to obtain a mixed solution, wherein the solvent A comprises at least one of protonic acid, aromatic solvent, ether, pyrrolidone, alkyl halide and alkylene halide, and preferably the solvent A comprises at least one of trifluoroacetic acid, toluene, tetrahydrofuran, methyl pyrrolidone, chloroform and alkylene halide;

(3) adding the mixed solution obtained in the step (2) into a non-solvent for quenching, and precipitating to obtain a phthalocyanine eutectic intermediate, wherein the non-solvent comprises at least one of water, alcohol and ketone;

(4) and treating the phthalocyanine eutectic intermediate by adopting an aromatic solvent to obtain the phthalocyanine eutectic, wherein the aromatic solvent comprises at least one of aromatic hydrocarbon, aromatic nitro compound and aromatic halide.

The crystal form of the oxytitanium phthalocyanine coarse crystal is I type, and any type I oxytitanium phthalocyanine can be used as the starting material of the method. The type I oxytitanium phthalocyanines of the present invention are readily available and may be obtained by any of the presently disclosed suitable methods, including, but not limited to, the methods disclosed in U.S. Pat. Nos.5153094, 5166339, 5189155 and 5189156.

The type I oxytitanium phthalocyanine of the present invention may be prepared from DI³(1, 3-diiminoisoindolene, 1,3-diiminoisoindolene) and titanium tetrabutoxide are reacted in the presence of a 1-chloronaphthalene solvent, and are washed and refined by dimethylformamide until the purity of the type I oxytitanium phthalocyanine crude crystal reaches 99.5 percent.

The type I oxytitanium phthalocyanine can also be prepared by reacting 1,3-diiminoisoindole, phthalonitrile and tetrapropanol titanium salt in the presence of N-methylpyrrolidone solvent to obtain type I oxytitanium phthalocyanine crude crystals, and cleaning and refining the type I oxytitanium phthalocyanine crude crystals by using dimethylformamide until the purity of the type I oxytitanium phthalocyanine crude crystals reaches 99.5 percent.

The metal-free phthalocyanine crude crystal form of the present invention is form X and can be obtained by any of the presently disclosed suitable processes, including but not limited to that disclosed in U.S. patent No. 6476219.

The metal-free phthalocyanine crude crystal can be obtained by refluxing phthalonitrile and ammonia gas in 2-dimethylaminoethanol or condensing phthalonitrile in hydroquinone solvent.

The metal-free phthalocyanine crude crystals of the present invention can be prepared by reacting an aqueous or alcoholic solution of an acid, and an alkali metal phthalocyanine selected from dilithio phthalocyanine, disodium phthalocyanine, dipotassium phthalocyanine, beryllium phthalocyanine, magnesium phthalocyanine or calcium phthalocyanine, and an acid including, but not limited to, hydrochloric acid, phosphoric acid, sulfuric acid, nitric acid, sulfonic acid or carboxylic acid and mixtures thereof.

Preferably, in the step (2), the solvent a comprises trifluoroacetic acid and an alkylene halide, preferably trifluoroacetic acid and dichloromethane;

the volume ratio of the trifluoroacetic acid to the alkylene halide is 1:10-10:1, preferably 2:8-8:2, the good dissolving capacity is realized, the subsequent formation of stable eutectic is facilitated, and the cost is low.

Preferably, the step (2) further comprises the step of standing the mixed solution after completely dissolving the oxytitanium phthalocyanine coarse crystals and the metal-free phthalocyanine coarse crystals, wherein the standing temperature is-25-145 ℃, and is preferably-10-50 ℃; the standing time is 10min-24h, preferably 30min-12h, so that enough time is provided for generating the phthalocyanine eutectic.

Preferably, in the step (3), the volume ratio of the mixed solution to the non-solvent is 10:90-90:10, preferably 25:75-75:25, so that excessive cost is avoided while sufficient precipitation is ensured;

the non-solvent may be selected from water; alcohols such as methanol, ethanol or isopropanol; a ketone, such as acetone, to precipitate a phthalocyanine eutectic intermediate.

The precipitated eutectic intermediate may be treated by any suitable means, for example by separating the eutectic intermediate from the remaining non-solvent by suction filtration, and the separated eutectic intermediate is washed with water, methanol or acetone, followed by methanol and deionized water until the conductivity of the wash liquid is less than 10 μ S.

The separated eutectic intermediate (with water content of about 30-70%) is converted into a new crystal form in aromatic solvent, so as to obtain the ideal eutectic. Suitable aromatic solvents include aromatic hydrocarbons such as benzene, toluene and xylene; aromatic nitro compounds such as nitrobenzene; aromatic halides such as monochlorobenzene, dichlorobenzene, trichlorobenzene and chloronaphthalene; and phenol.

Preferably, in the step (4), the weight ratio of the aromatic solvent to the phthalocyanine eutectic intermediate is 99:1-50:50, preferably 98:2-80: 20.

Preferably, the phthalocyanine eutectic intermediate is treated by the aromatic solvent for 1-7h, preferably 2-6h, and more preferably 3-5h, so that sufficient time is provided for converting the crystal form.

After the crystal form conversion is completed, the phthalocyanine eutectic is subjected to filtration separation, cleaning and drying treatment, for example, deionized water and acetone cleaning, and finally, the phthalocyanine eutectic is dried under vacuum to obtain the ideal phthalocyanine eutectic. Heating may be suitably carried out during the drying, for example, at a drying temperature of 50 to 90 ℃ and preferably 60 to 80 ℃.

The phthalocyanine eutectic crystal prepared by the invention can be distinguished by an X-ray powder diffraction pattern. The X-ray powder diffraction pattern can be measured by an X-ray diffractometer commonly used on the market, such as siemens D5000. The characteristic peaks of the phthalocyanine eutectic prepared by the invention comprise Bragg angles of 7.4 degrees, 9.0 degrees, 9.7 degrees, 14.2 degrees, 14.9 degrees, 24.1 degrees and 27.3 degrees. The particle size of the phthalocyanine co-crystals prepared by the invention prepared by the method according to the disclosure is 10-500 nm. The particle size of the phthalocyanine eutectic is controlled or influenced by the quench rate of the addition of the mixed liquor of dissolved eutectic to the quenching non-solvent and the composition of the non-solvent.

The invention also provides the use of the phthalocyanine eutectic in the preparation of an electrophotographic imaging member. The sensitivity of the phthalocyanine eutectic can be continuously adjusted according to the weight ratio of the oxytitanium phthalocyanine to the phthalocyanine without metal, and the phthalocyanine eutectic can be used as a photogenerating material in a charge generating layer of an electrophotographic imaging element in an electrophotographic or xerographic process.

The invention also provides an electrophotographic imaging member for use in an electrostatographic or xerographic process comprising a substrate, a charge generating layer and a charge transport layer, the charge generating layer comprising the phthalocyanine eutectic as described above.

The present invention is not particularly limited with respect to the configuration of the electrophotographic imaging member, including but not limited to the electrophotographic imaging member shown in fig. 1 and 2.

As shown in fig. 1, a negatively charged electrophotographic imaging member comprises a substrate 1, a hole blocking layer 2, a charge generating layer 3, and a charge transport layer 4, the charge generating layer 3 comprising a phthalocyanine eutectic prepared according to the present invention.

As shown in fig. 2, a positively charged electrophotographic imaging member includes a substrate 10, a charge transport layer 12, and a charge generating layer 14, the charge generating layer 14 including a phthalocyanine eutectic prepared according to the present invention.

The phthalocyanine eutectic is formed under the condition that the oxytitanium phthalocyanine and the phthalocyanine without metal are dissolved and mixed, so that the phthalocyanine without metal has enough freedom degree to replace the oxytitanium phthalocyanine crystal lattice to form stable eutectic. The chemical composition of the phthalocyanine eutectic is continuously adjustable, so that the sensitivity of the eutectic is also continuously adjustable. The weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine in the phthalocyanine co-crystal of the invention may be from 99:1-1:99, or from 95:5-50:50 is continuously varied. The greater the weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine, the higher the sensitivity of the oxytitanium phthalocyanine and metal-free phthalocyanine eutectic. When the phthalocyanine eutectic of the invention is applied to an electrophotographic imaging member, and the film thickness of a charge transport layer of a photoreceptor is 30 μm, the sensitivity of the photoreceptor varies with the weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine in the phthalocyanine eutectic, and the weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine in the charge transport layer is 99:1-1:99, then the photoreceptor has a Vcm from 200²/ergs-620Vcm²A sensitivity of/ergs, and the change in sensitivity is continuous; the weight ratio of oxytitanium phthalocyanine to phthalocyanine without metal in the phthalocyanine eutectic in the charge generating layer is 95:5-50: at 50, then the photoreceptor has a Vcm from 300²/ergs-550Vcm²Sensitivity of/ergs, and the change in sensitivity is continuous.

The phthalocyanine eutectic prepared in the present invention may be uniformly dispersed in a polymer selected from at least one of polycarbonate, polyvinyl butyral, polyvinyl chloride/polyvinyl acetate copolymer selected from at least one of polycarbonate A, Z, S, C, F, M, P, F and AP, polyvinyl butyral selected from S-L EC B L-1, BM-1, B L-S, BM-S, BX-L, BX-1, and the like, produced by Nippon hydro chemistry, including carboxylic acid modified polyvinyl chloride/polyvinyl acetate copolymers such as maleic acid modified polyvinyl chloride/polyvinyl acetate copolymer, VMCH produced by Dow chemistry, VINNO L E15/45M TF produced by Wacker polymer, VAMA produced by Xinfeng prefecture, and the like, to form the charge generating layer of an electrophotographic imaging member, the polymer is present in an amount of 20% to 95%, preferably 25% to 75%, and the corresponding phthalocyanine eutectic is present in an amount of from about 80% to about 5%, preferably from about 25% to about 75%, by weight.

In the preparation of the charge generating layer, the polymer is usually dissolved in a suitable solvent and then mixed with the phthalocyanine eutectic for dispersion, so that the phthalocyanine eutectic is better dispersed in the polymer. The solvent is selected not only in view of the solubility of the polymer, but also in view of the fact that the selected solvent does not adversely affect the phthalocyanine eutectic itself and other functional layers of the electrophotographic imaging member. Suitable solvents for the present invention include, but are not limited to, ketones, alcohols, aromatic hydrocarbons, halogenated aliphatic hydrocarbons, ethers, esters, amides and mixtures thereof, preferably cyclohexanone, acetone, isobutyl ketone, methanol, ethanol, butanol, pentanol, toluene, xylene, chlorobenzene, carbon tetrachloride, chloroform, dichloromethane, trichloroethylene, tetrahydrofuran, dioxane, diethyl ether, dimethylformamide, dimethylacetamide, butyl acetate, ethyl methoxyacetate and mixtures thereof.

Any suitable technique may be used to disperse the eutectic in the polymer solution to form the eutectic charge generation layer dispersion, including a grinder, ball mill, dynami LL ball mill, paint shaker, homogenizer, ultrasonic, microfluidizer, mechanical agitation, mixer, and other suitable grinding techniques.

Any suitable coating technique can be used to coat the phthalocyanine eutectic charge generating layer dispersion of the present invention on another functional layer of the photoreceptor to form a charge generating layer. Typical coating techniques include dip coating, roll coating, spray coating, rotary atomizer, flow coating, spin coating, extrusion, and the like.

The thickness of the charge generating layer is generally 0.05 to 5 μm, preferably 0.1 to 1 μm.

The charge generating layer containing the phthalocyanine eutectic of the present invention may be used in any known photoreceptor, such as single and multilayer photoreceptors, including but not limited to those disclosed in U.S. patent nos.6800411, 6824940, 6818366, 6790573 and U.S. patent application No. 20040115546. The photoreceptor generally comprises a substrate, a conductive layer, an optional hole blocking layer, an optional adhesive layer, a charge generating layer, a charge transport layer, and an optional protective layer.

Substrates of the invention include, but are not limited to, polyesters coated with a thin layer of titanium/zirconium alloy, such as DuPont

Aluminum/chromium/nickel/brass/stainless steel and their alloy pipes; plastics, cloth, glass and paper coated with a thin layer of a conductive metal oxide such as indium tin oxide, indium oxide, and metal drums and the like which have been subjected to metal oxidation treatment by electrode oxidation or the like.

The conductive layer of the substrate may optionally be coated with a hole blocking layer. The hole blocking layer includes a polymer and a metal oxide such as titanium oxide, zinc oxide, or the like uniformly dispersed in the polymer. The polymers include phenolic resins, polyurethanes, alkoxyalkylated polyamides and their crosslinking systems, crosslinked systems of polyvinyl butyral and polyisocyanate, polyhydroxyethylmethacrylate and its crosslinking systems, and similar thermosetting crosslinking systems. The thickness of the hole-blocking layer is 0.1 to 30 μm, preferably 0.5 to 10 μm.

The hole blocking layer may be coated with an adhesive layer having a thickness of 0.001 to 1 μm, preferably 0.01 to 0.2 μm. The adhesive layer is composed of a polymer comprising at least one of polyester, polyamide, polyvinyl butyral, polyurethane, polyvinyl alcohol.

A charge transport layer may also be coated on the charge generating layer. The charge transport layer is typically a charge transport material such as hole transporting small molecules uniformly dispersed in an inactive polymer. Non-living polymers include polycarbonates, such as polycarbonate Z, A, C and AP, having a weight average molecular weight of from 20000-. In addition, aromatic polyesters are also suitable for use as the dead polymer in the charge transport layer. The aromatic amines disclosed in U.S. Pat. No.4,265,990 may also be used in the charge transport layer as suitable hole transporting small molecules. In practice, the chemical structure of the aromatic amine is shown below:

and

wherein X is alkyl, halogen, alkoxy or a mixture thereof. Typically halogen is chlorine and typically alkyl has from 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms. Commonly used hole transporting small molecules include N, N-diphenyl-N, N-bis (3-methylphenyl) -1, 1-biphenyl-4, 4-diamine (mTBD), N-diphenyl-N, N-bis (4-methylphenyl) -1, 1-biphenyl-4, 4-diamine (pTBD), N-tetrakis (4-methylphenyl) -1, 1-biphenyl-4, 4-diamine, and N, N-diphenyl-N, N-bis (4-methoxyphenyl) -1, 1-biphenyl-4, 4-diamine.

In addition, other suitable power transmission materials are specifically described in Japanese patent laid-open No. 11-172003.

The weight ratio of the polymer to the hole transporting small molecule in the charge transport layer is from 80:20 to 30:70, preferably from 40:60 to 75: 25. The thickness of the charge transport layer is generally from 2 to 50 μm, preferably from 15 to 35 μm. The thickness ratio of the charge transport layer to the charge generating layer is generally from 2:1 to 200:1, and in some cases can be as high as 400: 1.

When the electrophotographic image forming element includes a charge generating layer, the charge generating layer dispersion may be coated on the adhesive layer, the conductive layer, or the charge transporting layer during the production process. When a charge generating layer and a charge transport layer are present together, the charge generating layer may be sandwiched between the surface of the conductive layer and the charge transport layer, or the charge transport layer may be sandwiched between the surface of the conductive layer and the charge generating layer.

In a multilayer photoreceptor, the charge generating layer, the charge transport layer, and other functional layers can be arranged in a suitable order to produce a positively or negatively charged multilayer photoreceptor either with the charge generating layer applied first and the charge transport layer applied second, or with the charge transport layer applied first and the charge generating layer applied second.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the phthalocyanine eutectic is prepared by adding a mixed solution of oxytitanium phthalocyanine and metal-free phthalocyanine into a proper non-solvent for quenching, and then performing crystal form conversion by adopting an aromatic solvent. The phthalocyanine eutectic has higher sensitivity, can be used as a photogenerating material for preparing a charge generating layer of an electrophotographic imaging element, and the sensitivity of the electrophotographic imaging element can be continuously adjusted according to the weight ratio of oxytitanium phthalocyanine to phthalocyanine without metal in the phthalocyanine eutectic.

Drawings

FIG. 1 is a schematic structural view of a negatively charged electrophotographic imaging member having a charge generating layer comprising a phthalocyanine eutectic of the present invention;

FIG. 2 is a schematic illustration of a positively charged electrophotographic imaging member having a charge generating layer comprising a phthalocyanine eutectic according to the present invention;

FIG. 3 is a graph of the weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine 95: and 5, obtaining the X-ray diffraction pattern of the phthalocyanine eutectic crystal.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to specific examples. It will be understood by those skilled in the art that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the examples, the experimental methods used were all conventional methods unless otherwise specified, and the materials, reagents and the like used were commercially available without otherwise specified.

Preparation of phthalocyanine co-crystals

Example 1: preparation of type I oxytitanium phthalocyanine coarse crystal

A three-necked flask with a mechanical stirrer, condenser and thermometer under argon atmosphere was kept, 3.6g of 1, 3-diiminoindoline and 9.6g of phthalonitrile were first dissolved in 75M L N-methylpyrrolidone, 7.1g of titanium tetrapropanolate were then slowly added, the mixture obtained was stirred and heated to reflux (198 ℃) for about 2h, the black suspension obtained was cooled to 150 ℃ and was then filtered through an M-porosity sintered glass funnel preheated with boiling dimethylformamide, the solid product obtained was washed in the funnel with dimethylformamide boiling at 150M L, slurried and filtered again, the solid obtained was washed in the funnel again with dimethylformamide boiling at 150M L, slurried and filtered again, the solid obtained was finally washed with 50M L methanol and dried overnight at 70 ℃ to give about 10g of violet solid (yield about 70%). the violet solid was confirmed to be type I titanylphthalocyanine phthalocyanine according to X-ray powder diffraction pattern.

The type I oxytitanium phthalocyanine can also be prepared in 1-chloronaphthalene by the following specific method:

a three-necked flask, with a mechanical stirrer, condenser and thermometer kept under argon atmosphere, was first charged with 14.5g of 1, 3-diiminoindolene dissolved in 75M L1-chloronaphthalene, followed by the slow addition of 8.5g of titanium tetrabutoxide, by stirring and heating the mixture, at 140 ℃ the mixture turned dark green and started to reflux, at which time steam (n-butanol, identified by gas chromatography) was allowed to escape into the atmosphere until the reflux temperature reached about 200 ℃ and the reaction was maintained at this temperature for 2h, then cooled to 150 ℃, and the suspension obtained was filtered by suction through an M-porosity sintered glass funnel preheated with boiling dimethylformamide, then washed with three portions of dimethylformamide boiling at 150M L, then with three portions of dimethylformamide at room temperature 150M L, and finally with three portions of 50M L methanol, 10g of the purple solid thus obtained (yield about 70%), which was identified as type I oxytitanium phthalocyanine by X-ray powder diffraction pattern.

Example 2: preparation of X-type metal-free phthalocyanine coarse crystal

14.1g of phthalonitrile was dissolved in 50m L2-dimethylaminoethanol and then 7.7g of ammonium acetate was added, the mixture was stirred and heated to about 120 ℃ for 15min, then heated to reflux (about 140 ℃) for 6h, then the dark blue-green solution was diluted with 100m L dimethylformamide and cooled to room temperature, the solid was separated and washed with four portions of 25m L dimethylformamide and then three portions of 100m L acetone, and the separated solid was dried by heating to 60 ℃ to obtain a blue solid which was confirmed to be X-type metal-free phthalocyanine according to X-ray powder diffraction pattern.

Example 3: preparation of Phthalocyanine cocrystals (weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine 95:5)

In a 500m L conical flask, type 47.5g I oxytitanium phthalocyanine (example 1) and type 2.5g X metal-free phthalocyanine (example 2) were dissolved in a 300m L trifluoroacetic acid-dichloromethane mixed solvent (the volume ratio of trifluoroacetic acid to dichloromethane is 1: 4), and the mixture was left for 1 hour;

cooling 2600m L methanol in ice salt water bath until the final temperature is about-10 deg.C, adding the mixed solution with dissolved oxytitanium phthalocyanine and metal-free phthalocyanine into the mixed solvent within 60min, quenching, and stirring for 30 min;

the mixture was subjected to hose vacuum filtration through a 2000m L buchner funnel with fibrous frit having porosity of 4-8 μm and the obtained solid was mixed with 1500m L methanol and vacuum filtered, then the solid was mixed with 1000m L hot water (hot water temperature greater than 90 ℃) and vacuum filtered four times, finally the solid was mixed with 1000m L cold water and vacuum filtered, the conductivity of the final filtrate was measured to be less than 10 μ S, the obtained wet cake contained about 50% water, the obtained wet cake was redispersed in 700g monochlorobenzene and stirred for 2h and the dispersion was subjected to hose vacuum filtration through a 2000m L buchner funnel with fibrous frit having porosity of 4-8 μm within 2h, finally the solid was mixed well with 1500m L methanol and vacuum filtered twice in the funnel, the obtained blue solid was vacuum dried at 60-65 ℃ for two days to obtain about 45g of solid phthalocyanine eutectic.

The X-ray powder diffraction pattern of the phthalocyanine eutectic is shown in fig. 3, and the phthalocyanine eutectic has characteristic peaks including bragg angles of 6.8 degrees, 7.4 degrees, 9.0 degrees, 9.7 degrees, 11.6 degrees, 13.5 degrees, 14.2 degrees, 14.9 degrees, 18.0 degrees, 24.1 degrees and 27.3 degrees.

Example 4: preparation of Phthalocyanine cocrystals (weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine 90:10)

In a 500m L conical flask, 45g I type oxytitanium phthalocyanine (example 1) and 5g X type metal-free phthalocyanine (example 2) were dissolved in a 300m L mixed solvent of trifluoroacetic acid and dichloromethane (the volume ratio of trifluoroacetic acid to dichloromethane is 1: 4), and left for 1 h;

cooling 2600m L methanol in ice salt water bath until the final temperature is about-10 deg.C, adding the mixed solution with dissolved oxytitanium phthalocyanine and metal phthalocyanine without containing into the mixed solvent for quenching within 60min, and stirring for 30 min;

the mixture was vacuum filtered through a hose through a 2000m L buchner funnel with a fibrous frit having a porosity of 4-8 μm, followed by mixing the obtained solid with 1500m L methanol and vacuum filtering, then the solid was well mixed with 1000m L hot water (hot water temperature greater than 90 ℃) and vacuum filtered four times, finally the solid was mixed with 1000m L cold water and vacuum filtered, the conductivity of the final water filtrate was measured to be less than 10 μ S, the obtained wet cake contained about 50% water, the obtained wet cake was redispersed in 700g monochlorobenzene and stirred for 2h, and the dispersion was vacuum filtered through a hose through a 2000m L buchner funnel with a fibrous frit having a porosity of 4-8 μm within 2h, finally the solid was mixed with 1500m L methanol and vacuum filtered twice in the funnel, the obtained blue solid was vacuum dried at 60-65 ℃ for two days to obtain about 45g of solid phthalocyanine co-crystal.

Example 5: preparation of Phthalocyanine cocrystals (weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine 80:20)

In a 500m L Erlenmeyer flask, 40g of type I oxytitanium phthalocyanine (example 1) and 10g of type X metal-free phthalocyanine (example 2) were dissolved in a 300m L mixed solvent of trifluoroacetic acid and dichloromethane (the volume ratio of trifluoroacetic acid to dichloromethane is 1: 4), and left for 1 h;

2600m L methanol was cooled in a bath of ice salt water until the final temperature was about-10 deg.C. the mixture of dissolved oxytitanium phthalocyanine and metal-free phthalocyanine was quenched by adding to the mixed solvent over 60min, and then the mixture was stirred for 30 min;

the mixture was subjected to hose vacuum filtration through a 2000m L buchner funnel with fibrous frit having porosity of 4-8 μm, followed by mixing and vacuum filtration of the obtained solid with 1500m L methanol, followed by mixing and vacuum filtration of the solid with 1000m L hot water (hot water temperature greater than 90 ℃) four times, finally mixing and vacuum filtration of the solid with 1000m L cold water, measuring the conductivity of the final filtrate to be less than 10 μ S, the obtained wet cake containing about 50% water, redispersing and stirring the obtained wet cake in 700g monochlorobenzene for 2h, and subjecting the dispersion to hose vacuum filtration through a 2000m L buchner funnel with fibrous frit having porosity of 4-8 μm within 2h, finally mixing and vacuum filtration of the solid with 1500m L methanol twice in a funnel, the obtained blue solid was vacuum dried at 60-65 ℃ for 60-65 ℃ to obtain about 45g of solid phthalocyanine eutectic.

Fabrication of photoreceptor devices

By fabricating a plurality of photoreceptor devices to compare various properties of different photovoltaic materials in a photoreceptor, the configuration of the photoreceptor devices is: the hole blocking layer is arranged on the aluminum alloy tube substrate.

All devices used the same aluminum alloy tube substrate, hole blocking layer and charge transport layer, and different phthalocyanine charge generation layers prepared from the coating dispersions prepared in examples 6 to 8 and comparative examples 1 to 2, respectively.

A dispersion of a hole-blocking layer coating is prepared by mixing 8 parts of titanium dioxide powder (TiO 2 MT-150W of the Japan Imperial chemical industry) and 7 parts of methoxymethylated polyamide 6 (FINE of L td. Co., Namariichi Co., Japan)

FR101) and 85 parts of ethanol were ball-milled with 400 parts of 1.0 to 1.25 mm zirconia beads for 4 h; this hole-blocking layer dispersion was coated on an aluminum alloy pipe substrate having a diameter of 30 mm and dried at 80 ℃ for about 6min to obtain a hole-blocking layer having a thickness of 2 μm.

Example 6: weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine 95:5 preparation of phthalocyanine eutectic charge generation layer coating dispersion

3 parts of the phthalocyanine cocrystal of example 3, 1 part of polyvinyl butyral (S-L EC BM-S from Japan hydrographic chemistry) and 96 parts of butyl acetate are milled for 2h together with 400 parts of 1.0 to 1.25 mm glass beads.

Example 7: weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine 90:10 preparation of phthalocyanine eutectic charge generation layer coating dispersion

3 parts of the phthalocyanine cocrystal of example 4, 1 part of polyvinyl butyral (S-L EC BM-S from Japan hydronic chemistry) and 96 parts of butyl acetate are milled for 2h together with 400 parts of 1.0 to 1.25 mm glass beads.

Example 8: weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine 80: preparation of 20 phthalocyanine eutectic charge generation layer coating dispersion

3 parts of the phthalocyanine cocrystal of example 5, 1 part of polyvinyl butyral (S-L EC BM-S from Japan hydrographic chemistry) and 96 parts of butyl acetate are milled for 2h together with 400 parts of 1.0 to 1.25 mm glass beads.

Comparative example 1: preparation of oxytitanium phthalocyanine charge generating layer coating dispersion liquid with higher sensitivity in market

3 parts of commercially higher sensitivity oxytitanium phthalocyanine (available from IT CHEM, Korea), 1 part of polyvinyl butyral (S-L EC BM-S, Japan hydrographic chemistry) and 96 parts of butyl acetate were milled for 2 hours with 400 parts of 1.0-1.25 mm glass beads.

Comparative example 2: preparation of commercially lower sensitivity oxytitanium phthalocyanine charge generation layer coating dispersion

3 parts of a commercially lower sensitivity oxytitanium phthalocyanine (available from A L P-CHEM), 1 part of polyvinyl butyral (S-L EC BM-S of Japan hydrographic chemistry) and 96 parts of butyl acetate were milled for 2 hours with 400 parts of 1.0-1.25 mm glass beads.

The coating dispersions of the charge generating layers of examples 6 to 8 and comparative examples 1 to 2 were coated on the hole-blocking layer, respectively, and dried at room temperature to obtain a charge generating layer having a thickness of 0.2 μm.

The preparation method of the power transmission layer coating solution comprises the following steps: 8 parts of N, N '-diphenyl-N, N' -bis (4-methylphenyl) -1,1 '-biphenyl-4, 4' -diamine (pTBD) and 10 parts of polycarbonate Z (PCZ-500, Mw ═ 50,000, mitsubishi gas chemical, japan) were dissolved in a mixed solvent of 57.4 parts of tetrahydrofuran and 24.6 parts of toluene. The electricity transport layer coating solution was coated on the phthalocyanine charge generating layer and dried at 135 ℃ for 45min to obtain an electricity transport layer having a thickness of 21 μm.

In this example, we did not measure the proxy electrical property of the PIDC directly, but rather, printed the photoreceptor directly in a printer to obtain a true reflection of the electrical properties.

From the 1 st jetness, the sensitivity of the phthalocyanine eutectic of the invention is between the higher and lower sensitivity oxytitanium phthalocyanines on the market. The present invention allows the sensitivity of the co-crystal to be continuously tunable by incorporating a metal-free phthalocyanine in the oxytitanium phthalocyanine lattice. From the 1000 th sheet, the jetness of all photoreceptors had a similar proportional reduction, indicating that the electrical properties of the phthalocyanine co-crystal of the invention other than the photoreceptor are similar to those of commercially available oxytitanium phthalocyanine. To our present knowledge, we believe that the sensitivity of the embodiment photoreceptor has the following order: comparative example 1 [ highly sensitive oxytitanium phthalocyanine ] example 6 [ oxytitanium phthalocyanine and metal-free phthalocyanine in weight ratio 95: phthalocyanine eutectic of 5 > example 7 [ oxytitanium phthalocyanine and metal-free phthalocyanine in a weight ratio of 90: phthalocyanine co-crystal of 10) > example 8 [ oxytitanium phthalocyanine and metal-free phthalocyanine in a weight ratio of 80: phthalocyanine co-crystal of 20) co-crystal > comparative example 2 [ hypo-allergenic titanyl phthalocyanine ]. Thus, by adjusting the weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine in the phthalocyanine eutectic, the desired sensitivity of the electrophotographic imaging member can be adjusted accordingly.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. The phthalocyanine eutectic is formed by oxytitanium phthalocyanine and phthalocyanine without metal, wherein the weight ratio of the oxytitanium phthalocyanine to the phthalocyanine without metal is 99:1-1: 99.

2. The phthalocyanine eutectic according to claim 1, wherein the weight ratio of oxytitanium phthalocyanine to metal-free phthalocyanine is 95:5 to 50: 50.

3. The process for the preparation of phthalocyanine co-crystals according to claim 1 or 2, characterized in that it comprises the following steps:

(4) and treating the phthalocyanine eutectic intermediate by adopting an aromatic solvent to obtain the phthalocyanine eutectic, wherein the aromatic solvent comprises at least one of aromatic hydrocarbon, aromatic nitro compound, aromatic halide and phenol.

4. The process for the preparation of phthalocyanine co-crystals according to claim 3, wherein in step (2), solvent A comprises trifluoroacetic acid and an alkylene halide, preferably trifluoroacetic acid and dichloromethane;

the volume ratio of the trifluoroacetic acid to the alkylene halide is 1:10-10:1, preferably 2:8-8: 2.

5. The preparation method of the phthalocyanine eutectic crystal according to claim 4, wherein the step (2) further comprises the step of standing the mixed solution after completely dissolving the oxytitanium phthalocyanine crude crystal and the metal-free phthalocyanine crude crystal, wherein the standing temperature is-25 ℃ to 145 ℃, and preferably-10 ℃ to 50 ℃; the standing time is 10min-24h, preferably 30min-12 h.

6. The method for preparing a phthalocyanine eutectic crystal according to claim 3, wherein in the step (3), the volume ratio of the mixed solution to the non-solvent is 10:90 to 90:10, preferably 25:75 to 75: 25.

7. The method for preparing a phthalocyanine eutectic crystal according to claim 3, wherein in the step (4), the weight ratio of the aromatic solvent to the phthalocyanine eutectic crystal intermediate is 99:1-50: 50.

8. The method for preparing a phthalocyanine eutectic crystal according to claim 7, wherein in the step (4), the weight ratio of the aromatic solvent to the phthalocyanine eutectic crystal intermediate is 98:2 to 80: 20.

9. Use of the phthalocyanine eutectic of claim 1 or 2 in the preparation of an electrophotographic imaging member.

10. An electrophotographic imaging member for use in an electrostatographic or xerographic process comprising a substrate, a charge generating layer and a charge transport layer, the charge generating layer comprising the phthalocyanine eutectic crystal of claim 1 or 2.