DE2513190A1 - PHOTOCULATIVE MASS AND THEIR USE - Google Patents

Description

Photoconductive compounds and their uses

The invention relates to a photoconductive composition containing an insulating polymeric matrix and a compound of formula

wherein

Ar anthryl, naphthyl, pyrenyl, indolyl, N-alkyl-2-carbazyl, Julolidinyl and the substituted analogs thereof, wherein the substituents are capable of electrons to the To give up centers within the compound with relative electron deficiency,

X denotes —NO ₂ or halogen and η can be in the range from 1 to 5.

These masses have a good spectral response in the visible Area of the electromagnetic spectrum and can be used in electrostatographic imaging elements and in imaging processes be used.

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The invention relates to a mass, an imaging element and an imaging method. The compositions according to the invention are highly effective photogenerator materials and can therefore in electrophotographic imaging elements and in imaging processes be used.

The formation and development of images on the imaging surfaces of photoconductive materials by electrostatic measures are well known. At the Best known technique, commonly known as xerography, is a latent electrostatic Image is formed on the imaging surface of an imaging element by removing the surface of the imaging layer first uniformly electrostatically charges in the dark and then this electrostatically charged surface with one Light and shadow image exposed. The areas of the imaging layer struck by light thus become relatively conductive and the electrostatic charge is selectively consumed in these exposed areas. After the photoconductor has been exposed, the electrostatic latent image of that surface bearing the image is developed with it a finely divided, colored »electroscopic ma + crial, known as "toner" is made visible. This toner is mainly attracted to the areas of the surface containing the image that retain the electrostatic charge, and thus a visible powder image is formed.

The developed image can then be read or permanently affixed to the photoconductor when the imaging layer is in place is not reused. This latter method is commonly used with binder-type photoconductive films performed (e.g. zinc oxide / insulating resin binder) where the photoconductive imaging layer is an integral part of the finished copy (see US Pat. Nos. 5,121,006 and 3 121 007).

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In the so-called copier systems with "plain paper" the latent image can be developed or based on the imaging surface of a reusable photoconductor another surface can be transferred like on a sheet of paper and then developed. If the latent Image is developed on the imaging surface or on a reusable photoconductor, it is often based on transferred to another substrate and then permanently fixed to it. To keep the toner image on the sheet of paper permanently one can use any of the well known methods including overcoating with one transparent film or you can use solvents or thermal fusing of the toner particles to the Carrier substrate.

With the above copier systems "with plain paper" should the materials that are used in the photoconductive layer are preferably able to be rapidly removed from the insulating to be switched to the conductive and the insulating state so that the imaging surface can be used cyclically can. The failure of a material, 'to its relatively insulating To return to the state before the subsequent loading / imaging sequence requires an increase in the Speed of dark decay of the photoconductor. The phenomenon often referred to as "fatigue" has been avoided in the past by selecting photoconductive materials that have fast switching capacitance. Examples of materials that can be used in such fast cycling imaging systems are Anthracene, sulfur, selenium and mixtures thereof (US Pat. No. 2,297,691), with selenium being superior because of its Photosensitivity is preferred.

In addition to anthracene, other organic photoconductive materials have been used in electrophotography (See US Pat. No. 3,037,861) $ of these materials is poly- (N-

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vinylcarbazole) is the best known. Until recently, ".. none of these organic materials have been seriously considered as alternatives to inorganic photoconductors such as selenium due to manufacturing difficulties and / or the relative lack of speed and photoconductivity within the visible region of the electromagnetic spectrum. The recent discovery that high loadings of 2,4,7-trinitro-9-fluorenone in polyvinyl carbazoles greatly improve the photosensitivities of these polymers, has led to renewed interest in organic photoconductive materials (US Pat. No. 3,484,237) Loading with such activators lead to phase separation of the various materials in such masses, and this is usually the case.There are therefore areas in these masses with an excess of activator, areas with a deficiency of activator and areas with the appropriate stoichiometric ratio of Activator to photoconductor on. The maximum amount of activator that can be added to most polymeric photoconductive materials without such phase separations occurring occasionally will not exceed about 6 to about 8 weight percent .

One method that has been proposed to overcome the difficulties associated with the use of such activators polymer photoconductors inherent to avoid is the direct incorporation of the activators into the polymeric backbone of the photoconductor (see US Pat. No. 3,418,116) This process involves the copolymerization of a vinyl monomer with an aromatic and / or heterocyclic substituent which has an electron donor function with a vinyl monomer with an aromatic and / or heterocyclic substituent that has an electron accepting function exercises, described. The spatial constraint or the spatial tension that affects such centers with different electron densities is exercised, favors the transfer of charge

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Intermediate effect in the photoexcitation of such masses. The so-called "intramolecular" charge transfer complexes, more precisely referred to as "intrachain" charge transfer complexes, act in essentially the same way as charge transfer complexes formed between small activator molecules and a photoconductive polymer. Obviously, the fact that the electron donating function and an electron accepting function occur on a common polymeric backbone does not change the ff "//" charge transfer interaction, but only increases the likelihood that it will occur. However, the preparation of such polymers from vinyl monomers with electron donor centers and vinyl monomers with electron acceptor centers is often difficult.

The preparation of the non-polymeric, photoconductive tricyanovinyl compounds, in which an electron-rich center and an electron-poor center are contained within a common molecule, is described in US Pat. No. 3,721,552 (corresponding to Australian patent application 36,760 / 68, published October 10, 1969 ). We will describe the production of photoconductive ^ ties! Ttel ^ -Schlchten by dispersion vcn about 10 to about 90 wt .. parts of this new Tricyanovinylverbindungen in about 90 to about 10 parts by weight Harzbindeaittel. The binder resins that can be used in forming the photoconductive insulating layer must have one

electrical specific volume resistance over 10 ohm-cm own. In fact, it describes all binders traditionally used in the manufacture of electrophotographic Imaging elements can be used for the preparation of these make layers are suitable. Since that preferred weight ratio of photoconductive particles to binder resin is 1: 1, it is apparent that the applicant of the patent mentioned has not recognized that significantly lower loadings with these compounds in a charge transport matrix deliver results that are equiva-

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lent to the results obtained with the compositions described as preferred. By minimizing the amount of photoconductive compound required to achieve a satisfactory photo response, the inherent physical properties of the binder resin that forms the film (e.g., flexibility, adhesion, and resistance) can be maintained the surface free energy).

It is an object of the present invention to provide a new class of photogenerator compounds which can be used in photoconductive compositions. The aim is to form photogenerator compounds with a high extinction coefficient.

According to the invention, a photogenerator connection is to be created in which the charge transfer interaction between Donor and acceptor sites occur regardless of the relative concentration of the photogenerator compounds in the resin.

Photo-conductive masses are to be created that are in the show a broad spectral response in the visible region of the electromagnetic spectrum.

According to the invention, imaging elements are to be created wherein the imaging layer is made from the above compositions, and an imaging method is also intended to be provided using these imaging elements.

The invention relates to photoconductive compositions that an insulating polymeric matrix and a bond of the formula

0 9 8 41/10 3 1

ORlGiNAL

contain, in which

Ar anthryl, naphthyl, pyrenyl, indolyl, N-alkyl-2-carbazyl, Julolidinyl and the substituted analogs thereof means in which the substituents are electrons relative to the can give up electron-poor centers within the compound,

X denotes -NO2 or halogen and η ranges from 1 to 5.

In preferred embodiments of the invention, the the above polymeric matrix also charged carriers which are formed during the photoexcitation of the above compound, transport quickly and effectively. In such preferred embodiments of the invention, the concentration is on Photogenerator compound typically less than 50 wt. 56.

The compositions of the invention can be prepared by adding one or more of the photogenerator compounds described above and the various other materials of the insulating polymeric matrix in a common solvent mixed and the resulting solution poured onto a suitable (preferably conductive) substrate or coated with it. The relative concentration of the photogenerator compound to insulating polymeric resin in such masses will be vary according to the transport capabilities of the matrix materials. The insulating polymeric matrices used in the The present invention can be either "electronically active" or "electronically inert". the Classification of the matrix as active or inert is determined by the relative ability of the matrix when used together with the photogenerator is used for charge transport. Such materials that contain at least one species of the photo-formed Can transport charge carriers are referred to as electronically active and the insulating polymers Matrix is referred to as the "active matrix". Accordingly, such materials that the transport of at least one

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Species of photo-formed charge carriers do not show up as electronically inert and are said to be insulating polymers Matrix is classified as an "inert matrix". The electronic activity (or inertia) of a matrix is therefore said to be two different Describe relationships that both must occur; the ability (or inability) of the matrix to produce a Injection of photo-formed charge carriers, into their mass, allow, and the ability (or inability) of Matrix to transport such injected charge carriers through their mass without inclusion «

In fact, any of the polymeric binders described in the literature can be used in conjunction with those of the present invention Photogenerator compounds can be used. Examples of electronically inert binders which can be used in the compositions of the invention Epoxy resins, poly (vinyl chloride), poly (vinylacetate), polystyrene), Poly (butadiene), poly (methacrylate), poly (acrylic compounds), Poly (acry! Nitrile), silicone resins, chlorinated elastomers, phenoxy resins, phenolic resins, epoxy / phenolic copolymers, Epoxy / urea / formaldehyde terpolymers, epoxy / Melamine / formaldehyde resins, poly (carbonates), poly (urethanes), Poly (amides), saturated poly (ester) copolymers, and mixtures thereof. Electronically active polymers used as a matrix for the photogenerator compound that can be used include poly- (N-vinylcarbazole), poly- (2-vinylcarbazole), poly- (3-vinylcarbazole), Poly (vinyl pyrene), poly (vinyl naphthalene), poly (2-vinyl anthracene) and poly (9-vinyl anthracene). Electronically active matrices can also be created by combining a or more of the above electronically inert polymers with one or more of the above electronically active polymers be used. The method for mixing or combining such electronically different polymers can copolymerization (random, graft, block, etc.), the formation of an interpenetrating polymer network or a polymeric blending. Alternatively, the electric

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nically inert polymer matrix can be formed as an effective means of transport for charge carriers by going inside a film made of such materials incorporates so-called "small molecules", which bring about effective carrier transport. The term "small molecules" is intended to mean any individual molecules and low molecular weight polymers include. These small molecules can become part of the casting or coating solution during the formation of the polymeric matrix be added or they can then be introduced into the matrix by the polymeric materials of the Can swell matrix in a solution that contains compounds with small molecules. When evaporating the liquid During the solution phase, the small molecules will remain trapped within the polymeric matrix, and thereby the carrier transport properties of this insulating film are improved. These small molecules can too be added to the active polymeric matrices in order to improve the transport of the charge carriers carried by the electronically active polymers are not easily transported. For example, a Lewis acid can become a photoconductive one Polymers such as poly (N-vinylcarbazole) are added to improve electron transport, examples of Addi-. Small molecule tives that are added to either an electronically active or inert polymeric matrix to facilitate the perforation or deficiency points (+) - transport Pyrene, anthracene, carbazole, triphenylamine, naphthalene, julolidine, indole and perylene. Small molecule additives, which can be incorporated into either an electronically active or an inert polymer matrix to prevent electron (-) transport to facilitate include anthracene, fluorenone, 9-dicyanomethylene fluorene, the nitro derivatives of fluorenone, the nitro derivatives of 9-dicyanomethylene fluorene and chloranil. Both hole or deficiency and electron transport materials with a small molecule can be used in combination with each other can be used in the inert polymers. It is known that a number of the above small molecules have charge transfer

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complexes with both the inert and the active polymer systems and a certain absorption of the Matrix complexes are allowed, provided that the absorptive capacity of the resulting charge transfer complex not with the Photogenerate! «connection competes in the Extent that the absorption band of the mass is determined by the absorption band of the complex. The absorbency of the charge transfer complex must also not interfere with the photogenerator connection of incident radiation shield. ·

The photogenerator compounds according to the invention, which correspond to the structural formula given above, are part of a unique class of compounds which contain both an electron withdrawing group and an electron donating group ₃ which are connected to one another by a spatially constrained bond, thereby ensuring that during photoexcitation of the polymeric matrix containing such compounds, the electronic transition moment from the ground state to the excited state and the flow of charge between the two groups are colinear. The formation of charge carriers b'ex the photoexcitation of these compounds is highly effective ^{even at very low concentrations (<> Λ} - ^/ 6% by weight ). Of course, the polyisre matrix must be electronically active to the carrier, the '-sfUhi'ena aer exposure or radiation are formed with electromagnetic radiation, transport to könnsn at such low loadings. In preferred embodiments of the present invention, the concentration of photogenerator compound in an electronically active matrix is in the range as low as about 0.1 to about 6 wt. At such low concentrations, the photoconductive mass can be referred to as a solid solution, that is, as a single phase hatch between the photogenerator compound and the polymeric material.

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rialien the matrix is formed, wherein the homogeneity is not due to the formation of a compound; See Van Norstrand's Scientific Encyclopedia, 4th Ed., D. Van Norstrand Company Inc., p. 1651 (1968). Are small molecules added to the polymeric materials to reduce the Increasing transport of one or both species of charge carriers can change the homogeneity of the mass somewhat.

At concentrations above 6 wt.% (Up to approximately one Maximum of about 99.9 wt.%) Decreases the inclination of the photogenerator connection, to crystallize within the matrix, too. As the crystallization increases, the physical properties of the polymer matrix and the ability of the photoconductive composition deteriorate Holding charges will also show a progressive decline.

As previously indicated, the compositions of the invention can be easily prepared by using the photogenerator compound and the film-forming, insulating polymer in the appropriate relative proportions in a common solvent mixed and then the resulting solution is poured onto a suitable substrate and coated or coated with it. covers. The amount of material coated on such substrates should be sufficient to produce a dry film having a thickness ranging from about 0.1 to about 200 microns. The exact thickness will be determined by end use of the element. Any of the substrates that. commonly used in the manufacture of electrophotographic Imaging elements used can be coated with the above solution. Typical substrates that Suitable in this regard include aluminum, chromium, nickel, brass, metallized plastic film, with metal coated plastic film (e.g. aluminized Mylar) and Conductive glass (e.g. tin oxide coated glass, NESA glass).

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After the electrophotographic imaging member is made the elements described above can be used in standard electrophotographic imaging processes can be used by simply sensitizing the surface of the photoconductive insulating layer of the element and then exposed the sensitized surface to a light and shadow image pattern. If the Photogenerator compound is dispersed in an electronically active polymeric matrix, the wavelength of the activating electromagnetic radiation preferably within the wavelength or the wavelength range of the substantial spectral response of the photogenerator compound and outside the range of the essential special response of the electronically active polymer matrix. After the formation of the latent electrostatic With the image on the element, the image can be transferred to another substrate or directly onto the imaging layer developed and then transferred. If one or more such photogenerator compounds are within of the electronically active polymer or an electronically active polymer that is a compound with a small molecule, the absorption spectra of the mass are characteristic of the individual components of this Mass, indicating that there is no discernible interaction between the photogenerator compound and the Matrix takes place.

At those masses where the relative concentrations of photogenerator compound adversely affect the charge storage capacity change the mass, films made from such masses can be treated with an insulating (electronic "Inert") polymer film are coated. The dielectric thickness of this coating must be sufficient to at least to carry some, if not all, of the sensitizing cargo. Such imaging elements seen with a coating "/ are designed for induction imaging systems

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submitted later}

- 13 -

as described in U.S. Patents 3,324,019, 3,676,117, and 3,653,064. The one in the The imaging system described in U.S. Patent 3,653,064 is the insulating coating of a uniform corona charge in the Subject to light (the polarity of the charge is immaterial). The sensitized imaging element is then provided with image information exposed, at the same time under a corona charge of opposite polarity. The imaged element is then exposed to shielded light and the latent image thus formed is developed with charged electroscopic toner particles, and then transferred to a receiving sheet.

The following examples explain the production and use of the compositions according to the invention. The procedures for The masses are produced and assessed using standard procedures or as described above. The parts and Unless otherwise stated, percentages in the examples are expressed by weight.

B e i s ρ i e 1 1

Production of 1- (2,4,6-trinitro styryl) pyrene

A mixture containing approximately 2.5 g (0 »01 mol) of pyrene-1-carboxaldehyde, 2.3 g (0.01 mol) of trinitrotoluene, 25 ml of ethanol and 0.25 ml of piperidine is placed in a reaction vessel under reflux conditions Heated for about 2 1/2 hours. The mixture is then allowed to stand over "Kraft" at room temperature, during which time fine brown, needle-like crystals form which separate from the solution. These crystals are recrystallized from ethanol; yield, 1.8 gp _p , 90-91 ° c.

About 5 parts by weight of 1- (2,4,6-trinitrostyryl) pyrene and 95 parts by weight of poly (N-vinylcarbazole) are in tetrahydrofuran dissolved and an aluminized mylar substrate is through

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Pull coated. The coated substrate is then placed in a vacuum oven and left there overnight. Sufficient solution is applied to the substrate to produce a polymer coating with a dry film thickness of approximately 35 microns. The polymer becomes intensely colored when mixed with the piezo generator compound, but it remains essentially homogeneous. The photoconductive insulating layer thus produced is sensitized by corona charging with a negative potential of about 600 volts. This sensitized surface is exposed through a quartz glass through cheinbila with a 100 watt tungsten lamp from a distance of 50 cm for a time sufficient to selectively discharge the exposed surface of the photoconductive insulating layer, thereby producing a latent electrostatic image. This electrostatic latent image is developed with positively charged toner particles and. the toner image is then transferred onto a sheet of untreated paper. Toner residues that remain on the surface of the nasty film are removed by wiping them with a soft cotton cloth. Before resensitization, the photoconductive insulating layer is generally exposed to ultraviolet light with a simultaneous positive corona charge. The copy cycle is repeated »The quality of the copies remains good and is reproducible,

JLJL ~ L · -§J £ lJL · JlJL «-, Jl

tsll ^ ig do. M-'Itä3fl »3 = - £ Eeta / lfadeI-5

In a 2000 nI-DreilialskoIuezi-, which is equipped with an icagnetisehan Rülirstaub, a Tfe-ss nonater uc4 elsisr EinlsSrchre for nitrogen _f there is 400 ml of anhydrous Di ^ -s-'thy.lj'Ormamic'.i 220 ml of water i-rslen Ithyiätiier vmu 59 ^, 36 g (C * ^ 22 MoI) 3-M-5thyliRdcIyl (srhaltellch you £ Ldrlch Chemical Compaaiy) ^ Mackdes ά 3ν contents of the fcsloea.6 is well -mixed, be about 64 _f 8 ^ g (0 ₃ 26 mole) fnalli ^ s (l) ~ ätlwlat added to the solution and represent Kolfcon. then on

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40 ° C heated with stirring for about 60 minutes, wherein the reaction mixture takes on a metallic appearance during this time. At the end of this time, 41.33 g (0.26 mol) ethyl iodide added to the flask, whereupon an orange colored, finely divided material separates out. the Reaction mass is heated to a temperature of about 50 to 55 ° C with constant stirring for a further 3 hours, cooled and the solids are separated from the reaction mass by filtration. The filtrate is made with water dilutes and separates into two distinct phases. The ether phase is set aside and the aqueous phase is extracted several times with chloroform. All of the organic layers are then reunited and reused several times Extracted water to remove residual traces of dimethylformamide. The ether phase is over anhydrous magnesium sulfate dried and evaporated to an oily residue. This residue is distilled at 80 ° C (0.2 mm) and the The fraction collected at this temperature is analyzed and found to be N-ethyl-3-niethylindole. In a 250 ml, three neck, round bottom flask fitted with a nitrogen inlet tube, magnetic stir bar, and thermometer is equipped, 3 is 17.47 ml of dimethylformamide. The flask and its contents are cooled in an ice bath and 21.29 ml of POCl are added dropwise. The flask is then placed in a room temperature oil bath and weighs 36.6 g (0.23 mol) N-ethyl-3-methylindole in 25 ml dimethylformamide are added dropwise. The implementation of these materials is strongly exothermic and the temperature of the bath is at Maintained 40 ° C while these materials are mixed and the reaction for an additional 3 hours at that temperature can expire. Towards the end of this time, the reaction mixture is poured into approximately 1 l of water with stirring and the resulting solution is triturated with sodium hydroxide until it reacts somewhat basic (approximately 7 ml become base added to the solution). An oily residue product that forms is extracted with chloroform, the chloroform

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2513130

is evaporated and the product is purified by vacuum distillation; the yield is about 50%.

Example 3

Production of 5- (2,4,6-trinitrostyryl) -N-ethyl-3-iaethylindole

The above product is prepared in the same manner as described in Example 1 by adding equimolar amounts of N-ethyl-3-methylindole-5-earboxaldehyde and trinitrotoluene converts.

Example 4

Production of N-Ethylindolo-3-carboxaldehyde

Indole-3-carboxaldehyde (available from Aldrich Chemical Comp.) is first purified by dissolving the commercially available material in hot tetrahydrofuran until the solution is saturated is. This saturated solution is then treated with charcoal to remove colored impurities, and then filtered. The hot filtrate is added to hot hexane until the first signs of precipitation appear Hexane solution is cooled overnight and the crystalline (Purified) indole-3-carboxaldehyde is obtained by filtration severed.

100 ml of anhydrous dimethylformamide and 80 ml of anhydrous ethyl ether are placed in a 500 ml reaction vessel equipped with a magnetic stirrer. The reaction vessel is now partially immersed in an oil bath and 14.2 g (0.098 mol) of indole-3-carboxaldehyde (purified) are added to the reaction vessel, followed by 24.9 g (0.1 mol) of thallium (I) ethylate added. The reaction mixture is then heated to a temperature in the range of about 35 to 4O ⁰ C with constant stirring over a period of about 20 minutes. Towards the end of this time, approximately 15.6 g (0.1 mol) of ethyl iodide are added to the reaction vessel and the

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Oil bath temperature is increased to approximately 55 ° C. Subsequent to the addition of the above materials and before increasing the The reaction vessel is equipped with a reflux condenser. The heating is carried out at the above temperature for about 60 minutes. A large amount of an orange / yellow precipitate is formed during this time. the The reaction mixture is allowed to cool to room temperature, it is filtered and the filtrate is poured into 1 l of water. The ether layer is separated and the water layer is extracted with chloroform. The chloroform extracts are combined with the ether part and the combined solution is re-extracted several times with water to remove residual traces to remove from dimethylformamide. The chloroform layer is then dried over anhydrous magnesium sulfate, filtered and evaporated while relaxing. An oily residue that remains is crystallized from cyclohexanone; yield 50 to 60% of colorless, platelet-like crystals, melting point 103 ° C.

Example 5

Production of 3- (2,4,6-trinitrostyryl) -N-ethylindole

The above product is in the same way \ rf.e described in Example 1 was prepared by mixing equimolar amounts of N-Äthylindol-3-carboxaldehyde and trinitrotoluene.

Example 6

Production of Julolidine-9-carboxaldehyde

A 200 ml three-necked flask fitted with an addition funnel, a magnetic stir bar and a reflux condenser with a calcium chloride drying tube attached to the reflux condenser, is equipped, is cooled in an ice bath. Following cooling, approximately 55.49 grams (0.75 moles) of dimethylformamide are added Pour into the flask and then add approximately 32.46 g (0.21 mol) of phosphorus (III) oxychloride with rapid stirring added. These two materials form when mixed together

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a reddish-orange complex. In a separate container, 36.5 g (0.21 mol) of julolidine are dissolved in dimethylformamide. The amount of dimethylformamide in this solution is the minimum amount required to dissolve the julolidine. This julolidine solution is then added to the addition funnel and gradually added dropwise to the flask over about 30 minutes. Following the mixing of these materials, the contents of the flask are heated on a steam bath for approximately 2 hours, then cooled to room temperature and neutralized to a low pH between 6 and 8 with approximately 200 ml of a saturated solution of sodium acetate and water. During this neutralization, the reaction mixture is stirred rapidly with sufficient cooling so that the temperature remains ^{at approximately 20 ° C.} The DMF / water layer is extracted three times with 200 ml portions of benzene and the benzene layer is washed three times with small portions of water. The benzene layer is then dried over anhydrous sodium sulfate. The benzene can slowly evaporate and a light green solid remains, which is then dissolved with hot cyclohexane. These solids form a dark green oily residue in the cyclohexane. This residue is then separated from the Cyclohe.xan. The cyclohexane solution is cooled and the crystals that separate in it are separated by filtration. Yield 28.8 g of julolidine-9-carboxaldehyde, mp. 77 to 79 ⁰ C.

Example 7

Preparation of 9- (2,4,6-trinitrostyryl) -julolidine

The above product is made by adding equimolar amounts of julolidone-9-carboxaldehyde and 2,4,6-trinitrotoluene mixed in the same manner as described in Example 1.

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Suitable photogenerators according to the invention are for example:

1- [β- (2,4,6-trinitrostyryl)] pyrene

1- [β- (2,4,6-trichlorostyryl)] pyrene

1- [β- (2,4,6-tribromostyryl)] pyrene

1- [β- (2,4-dinitrostyryl)] pyrene

2- [ß- (2,4,6-trinitrostyryl)] - 9-ethylcarbazole 2- [ß- (2,4,6-trichlorostyryl)] - 9-ethylcarbazole 9- [β- (2,4,6-trinitrostyryl)! -Julolidine 9- [ß- (2,4,6-trichlorostyryl)] - julolidine 9- [ß- (2,4,6-trinitrostyryl)] - anthracene 1- [β- (2,4,6-trinitrostyryl)] anthracene 2- [β- (2,4,6-trinitrostyryl)] anthracene 2- [β- (2,4,6-trinitrostyryl)! - naphthalene 1- [β- (2,4,6-trinitrostyryl)! - naphthalene 1-ethyl-3- [ß- (2,4,6-trinitrostyryl)] indole 1-ethyl-J-methyl-S- [ß- (2,4,6-trinitrostyryl)] indole 1-ethyl-3-methyl-5- [ß- (2,4,6-trichlorostyryl)] indole.

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Claims (25)

Claims Compound of formula Ar anthryl, naphthyl, pyrenyl, indolyl, N-alkyl-2 « carbazyl, julolidinyl and the substituted analogs thereof, wherein the substituents are capable of relative to the to give up electrons to electron-poor centers within the compound, X denotes -NOp or halogen and η ranges from 1 to 5. 2. Compound according to claim 1, namely 1- (2,4,6-trinitro styryl) pyrene. 3. Compound according to claim 'S, namely 9- (2,4,6 ~ trinitrostyryl) -anthracene. 4. A compound according to claim 1, namely N-ethyl-3-methyl-5- (2,4,6-trinitrostyryl) indole. 5. Compound according to claim 1, namely 9- (2,4,6-trinitrostyryl) -julolidine » 6. Photoconductive mass containing a solid solution of at least one photogenerator compound of the formula 50 98.41 / 1037 Ar anthryl, naphthyl, pyrenyl, indolyl, N-alkyl-2-carbazyl, Julolidinyl and the substituted analogs thereof, wherein the substituents are capable of relative to the to give up electrons to electron-poor centers within the compound, X is -NO ₂ or halogen and η is in the range from 1 to 5, and an insulating polymeric matrix, the polymeric matrix being capable of carrying charge carriers of at least one polarity to transport quickly and efficiently. 7. Composition according to claim 6, characterized in that that the photogenerator compound is 1- (2,4,6-trinitrostyryl) pyrene. 8. Composition according to claim 6, characterized in that that the photogenerator compound is 9- (2,4,6-trinitrostyryl) anthracene. 9. Composition according to claim 6, characterized in that that the photogenerator compound N-ethyl-3-methyl-5- (2,4,6-trinitrostyryl) indole is. 10. Composition according to claim 6, characterized in that that the photogenerator compound is 9- (2,4,6-trinitrostyryl) -julolidine. 11. A mass containing from about 0.1 to about 99.9 wt. # Of at least one photogenerator compound of the formula 509841/1037 Ar anthryl, naphthyl, pyrenyl, indolyl, N-alkyl-2-carbazyl, Julolidinyl and the substituted analogs thereof mean, wherein the substituents are capable of donating electrons to give up the relatively electron-deficient centers within the compound, X denotes -NOp or halogen and η is in the range from 1 to 5, in an insulating polymeric matrix, the minimum concentration of the photogenerator compound relative to the polymer matrix is sufficient to make the mass conductive 12, mass according to claim 11, characterized in that that the photogenerator compound is 1- (2,4,6-trinitrostyryl) pyrene. 13 .. mass according to claim 11, characterized in that that the photogenerator compound 9- (2,4,6-trinitrostyryl) -anthracene is. 14. Composition according to claim 11, characterized in that the photogenerator compound is N-ethyl-3-me- ^L : iyl-5- (2,4,6-trinitrostyryl) indole. 15. Composition according to claim 11, characterized in that that the photogenerator compound is 9- (2,4,6-trinitrostyryl) -julolidine. 16. Electrophotographisch.es imaging element containing a conductive substrate and a photoconductive, insulating layer effectively distributed therein, the photoconductive, The insulating layer contains a composition comprising from about 0.1 to about 99.9% by weight of at least one photogenerator compound the formula 5098-4 1 / Ί 0 37 Ar anthryl, naphthyl, pyrenyl, indolyl, N-alkyl-2-carbazyl, Julolidinyl and the substituted analogs thereof mean, wherein the substituents are capable of donating electrons to give up the relatively electron-deficient centers within the compound, X denotes -NOp or halogen and η is in the range from 1 to 5, in an insulating polymeric matrix, the minimum concentration of the photogenerator compound being relative to the polymeric matrix is sufficient to make the composition photoconductive. 17 mass according to claim 16, characterized in that that the photogenerator compound is 1- (2,4,6-trinitrostyryl) pyrene. 18. Composition according to claim 16, characterized in that the photogenerator compound 9- (2,4,6-trinitrostyryl) anthracene is. 19. Composition according to claim 16, characterized in that that the photogenerator compound N-ethyl-3-methyl-5- (2,4,6-trinitrostyryl) indole is. 20. Composition according to claim 16, characterized in that that the photogenerator compound 9- (2,4,6-trinitrostyryl) -julolidine is. 21. Electrostatographic imaging method, characterized in that one (a) an electrophotographic imaging member having a conductive substrate and a photoconductive insulating layer effectively distributed therein, the photoconductive insulating layer containing a mass approximately equal to 0.1 to about 99.9% by weight of at least one photogenerator 509841/1037 compound of formula Ar anthryl, naphthyl, pyrenyl, indolyl, N-alkyl-2-carbazyl, Julolidinyl and the substituted analogs thereof mean, wherein the substituents are capable of donating electrons to give up the relatively electron-deficient centers within the compound, X denotes -NOo or halogen and η is in the range from 1 to 5, in an insulating polymeric matrix, the minimum concentration of the photogenerator compound relative to the polymeric matrix being sufficient to render the composition photoconductive,
and you (b) forms an electrostatic latent image on the element. 22. The method according to claim 21, characterized in that the photogenerator compound 1- (2,4,6-trinitrostyryl) pyrene is. 23. The method according to claim 21, characterized in that the photogenerator compound 9- (2,4,6-trinitrostyryl) anthracene is. 24. The method according to claim 21, characterized in that the photogenerator compound N-ethyl-3-methyl-5- (2,4,6-trinitrostyryl) indole is. 25. The method according to claim 21, characterized in that the photogenerator compound 9- (2,4,6-trinitrostyryl) -julolidine is. 509841/1037