JPS6339902B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a photoconductive composition comprising a photoconductive material containing a novel thiopyrylium dye as a sensitizer. Thiopyrylium and pyrylium dyes are used in a variety of applications. For example, it is used as an electron-accepting compound in direct positive photographic silver halide emulsions as disclosed in Japanese Patent Publication No. 46-40900, as well as U.S. Pat. No. 3,141,700 by Davis et al.
U.S. patent by Van Allan et al.
It is useful as a sensitizer in photoconductors, particularly organic photoconductors, as described in US Pat. No. 3,250,615 and Reynolds et al., US Pat. No. 3,938,994. Photoconductors sensitized with thiopyrylium and pyrylium dyes are used in a variety of applications, such as those disclosed in the above-mentioned patent specifications, but they are particularly important for xerography and electrofax electrophotography. be. However, such conventionally known thiopyrylium dyes have a drawback of having multiple absorption bands in the visible region. In particular, almost all dyes also exhibit absorption in the blue region. That is, this sensitizing dye spectrally sensitizes in multiple wavelength ranges. Therefore, when this thiopyrylium dye is used as a sensitizer for photoconductive particles to carry out color copying, for example, when obtaining color images with trichromatic mixed particles by photoelectrophoretic electrophotography, it poses a serious problem. Collide. What is photoelectrophoresis electrophotography? U.S. Patent No. 3384448
As detailed in the specification, a suspension of photoconductive photosensitive particles in an insulating liquid is placed between two electrodes, at least one of which is transparent to light;
This is an electrophotographic method based on the fact that when a differential voltage is applied and light is exposed through a transparent electrode, the photoconductive photosensitive particles that have been exposed to this image selectively move to one of the electrodes, giving a visible image. When this electrophotographic method is applied to color copying, cyan particles that are sensitive to red light, magenta particles that are sensitive to green light, and yellow particles that are sensitive to blue light are used as photosensitive particles. If the mixed suspension is exposed to white light through a color slide using the above-mentioned apparatus, a color positive image or a color negative image can be obtained on the transparent electrode by a subtractive color method with one exposure. As disclosed in U.S. Patent No. 3,384,448, Japanese Patent Publication No. 43-21781, Japanese Patent Application Laid-open No. 52-143827, and elsewhere, the main absorption band of these particles mainly coincides with the main photosensitivity response. In addition to three-color photoconductive pigments such as cyan, magenta, and yellow, the photoconductor contains a spectral sensitizer to be sensitive to visible light, as described in U.S. Pat. No. 3,384,448. It is also possible to use photosensitive particles made to When a color image is obtained using three-color mixed particles by such electrophoretic electrophotography, when a known thiopyrylium dye is used as a spectral sensitizer for the photosensitive particles, it causes spectral sensitization in multiple wavelength ranges as described above. , only images with poor color separation could be obtained. That is, the known thiopyrylium dyes were unsuitable for color copying using photoelectrophoretic electrophotography. In order to solve the above-mentioned drawbacks, the present inventors have made repeated studies and found that the above-mentioned drawbacks of conventional thiopyrylium dyes have been improved, and in addition, they have a higher sensitizing ability for photoconductors than conventional thiopyrylium dyes. The present inventors have discovered a sensitizer consisting of a novel thiopyrylium dye having the following properties, and have completed the present invention. It is an object of the present invention to provide a photoconductive composition comprising a photoconductive material containing as a sensitizer a thiopyrylium dye that provides a high sensitizing ability to the photoconductor. A further object of the present invention is to provide a photoconductive composition comprising a photoconductive material containing a thiopyrylium dye as a sensitizer in order to obtain images with excellent color separation. The object of the present invention is achieved by using a thiopyrylium dye having the following structural formula as a sensitizer for photoconductive materials. However, in the formula, A is

【formula】

【formula】

[expression] or

A 2,6-di-t-butyl-4-substituted thiopyrylium salt, a method for producing the same, and a photoconductive composition containing the same. Z represents an anion. In the formula, X represents hydrogen, alkyl, aryl or substituted aryl group,
Substituents for substituted aryl groups include halogen, nitro, alkoxy and alkyl groups.
Preferably, as X, hydrogen, alkyl having 1 to 4 carbon atoms, phenyl, p-bromophenyl, p
-methoxyphenyl and p-tolyl groups. Further, R ¹ and R ² are the same or different alkyl groups, preferably an alkyl group having 1 to 4 carbon atoms. The thiopyrylium dyes used as sensitizers in photoconductive compositions according to the present invention are compounds having the following structural formula: and. ()2,6-di-t-butyl-4-(2,6-
Di-t-butyl-4H-thiopyran-4-ylidenemethyl)thiopyrylium salt. ()2,6-di-t-butyl-4-[3-(2,
6-di-t-butyl-4H-thiopyran-4-
ylidene)propen-1-yl]thiopyrylium salt and its derivatives (-a) 2,6-di-t-butyl-4-[3-(2,
6-di-t-butyl-4H-thiopyran-4
-ylidene)propen-1-yl]thiopyrylium salt. (-b) 2,6-di-t-butyl-4-[3-(2,
6-di-t-butyl-4H-thiopyran-4
-ylidene)-2-phenylpropene-1-
] Thiopyrylium salt. (-c) 2,6-di-t-butyl-4-[3-(2,
6-di-t-butyl-4H-thiopyran-4
-ylidene)-2-(4-bromophenyl)propen-1-yl]thiopyrylium salt. () 2,6-di-t-butyl-4-(4-dialkylaminophenyl)thiopyrylium salt (-a) 2,6-di-t-butyl-4-(4-diethylaminophenyl)thiopyrylium salt. () 2,6-di-t-butyl-4-(4-dialkylaminostyryl)thiopyrylium salt. (-a) 2,6-di-t-butyl-4-(4-diethylaminostyryl) thiopyrylium salt. (-b) 2,6-di-t-butyl-4-(4-dimethylaminostyryl) thiopyrylium salt. In the above formula, Z, R ¹ and R ² represent the same groups as described above. The anion represented by Z includes known single atomic ions or atomic group ions consisting of multiple atoms having a negative charge, preferably an anion of a strong acid represented by HZ with pKa of 5 or less, preferably pKa of 2 or less. be. Specific examples of anions include halogen anions such as fluoride ions, chloride ions, bromide ions, and iodide ions. Examples of atomic group ions include organic anions such as trifluoroacetate ion, trifluoroacetate ion, and p-toluenesulfonate ion, as well as perchlorate ion, periodate ion, tetrachloroaluminate ion, and trichlorofuerate (). ion, tetrafluoroborate ion,
Inorganic anions include hexafluorophosphate ion, sulfate ion, hydrogen sulfate ion, and nitrate ion. Among these, in the case of divalent anions, 1/2 of the anions are formally interpreted as representing monovalent anions. Among these anions, chloride ion, bromide ion, perchlorate ion, tetrafluoroborate ion, p-toluenesulfonate ion, and trifluoroacetate ion are preferred. To synthesize the above-mentioned thiopyrylium dye (), for example, 2,6-di-t-butyl-4
-(methyl)thiopyrylium salt and 2,6-di-t
-A method of reacting thiopyrylium salt with butyl-4-(methylthio)thiopyrylium salt in acetic anhydride.To synthesize thiopyrylium dye (2,6-di-t-butyl-4-(methyl)thiopyrylium salt and diphenylform) To synthesize thiopyrylium dye (), 2,6-di-t-butyl-4H-thiopyran-4-one is reacted with 4-diethylaminophylamine, followed by treatment with sodium acetate and acetic anhydride. To synthesize the thiopyrylium dye (2,6-di-
t-butyl-4-(methyl)thiopyrylium salt,
The method of reacting with 4-diethylaminobenzaldehyde in an alcohol in the presence of an amine or in acetic anhydride is advantageously employed. Also, thiopyrylium dye (-b) and (
-c) can also be produced by a method of heating 2,6-di-t-butyl-4-(methyl)thiopyrylium salt and benzoyl chloride or p-bromobenzoyl chloride in pyridine. ) is preferably produced by reacting 2,6-di-t-butyl-4-(methyl)thiopyrylium salt and 4-dimethylaminobenzaldehyde in acetic anhydride. In other thiopyrylium dyes, to obtain a compound where X is substituted aryl, 2,
6-di-t-butyl-4-(methyl)thiopyrylium salt and p-substituted benzoyl chloride,
For example, p-nitrobenzoyl chloride, p-
React with methoxy-benzoyl chloride, p-methyl-benzoyl chloride, etc. in pyridine. In addition, to obtain a compound in which X is an alkyl group, N,N-diphenylacetamidine or N,N
-diphenylpropionamidine etc. and 2,6-
and di-t-butyl-4-methylthiopyrylium salt. Further, other thiopyrylium dyes used in the present invention can be synthesized by the same method as above. The above-mentioned 2,6-di-t-butyl-4-(methylthio)thiopyrylium salt is described in "Jourmal of Heterocyclic Chemistry" by Reynolds et al.
2,6-di-t-butyl-4H-pyran- synthesized by the method described in Vol. 11, p. 1075 (1974)
4-one is (i) heated to reflux in a solvent in the presence of phosphorus pentasulfide to obtain 2,6-di-t-butyl-4H-pyran-4-thione, and (ii) this is converted into a highly polar After reacting with alkali hydrosulfide or alkali sulfide in a non-aqueous solvent under an inert gas flow to obtain 2,6-di-t-butyl-4H-thiopyran-4-thione, (iii)
It is synthesized through a three-step process of reacting this with a methylating agent. Further, the above 2,6-di-t-butyl-4H-thiopyran-4-one is synthesized by hydrolyzing the above 2,6-di-t-butyl-4-(methylthio)thiopyrylium salt. The above 2,6-di-t-butyl-4-(methyl)thiopyrylium salt is the 2,6-di-t-butyl-4-(methyl)thiopyrylium salt.
It can be synthesized by reacting 4H-thiopyran-4-one with a Grignard reagent and then treating it with an acid. For details on each of the above synthesis methods, please refer to the patent application published in 1983.
81523 (JP 56-7779), 54-81524 (JP 56-7780), 54-81525 (JP 56-7781)
(Japanese Patent Application No. 1983-37249), and Japanese Patent Application No. 1983-37249
129283). The thiopyrylium dyes used in the present invention are used as sensitizers in acid-free and organic photoconductive materials to improve the photoconductivity and sensitivity properties of various photoconductive materials. Inorganic photoconductive substances include zinc oxide, but particularly effective photoconductive substances are organic photoconductive substances. Organic photoconductive substances include low molecular compounds such as carbazoles such as carbazole and N-ethylcarbazole; triarylamines such as tri-p-tolylamine and triphenylamine; (In the formula, m is an integer of 2 to 4, n is an integer of 0 to 2,
R ³ , R ⁴ and R ⁵ are hydrogen, an alkyl group such as methyl, ethyl and propyl, and an aryl group such as phenyl and tolyl, and n+m≦4. ); fused aromatic ring compounds such as anthracene; aromatic compounds with unsaturated bonds such as tetraphenylbutadiene and tetraphenylhexatriene; and oxadiazole, thiadiazole, triazole,
These include unsaturated heterocycle-containing compounds such as imidazole, pyrazoline and various derivatives thereof, and examples of polymer compounds include poly-N-vinylcarbazole, brominated poly-N-vinylcarbazole, etc. Examples include vinylcarbazole derivatives; polyvinylanthracene; polyacenaphthylene; polyvinylacridine; polyvinylphenothiazine. Among these photoconductive materials are poly-N-vinylcarbazole; triarylamines such as tri-p-tolylamine and triphenylamine; 4,4'-bis(diethylamino)-2,2'-
Unsaturated heterocycle-containing compounds represented by polyarylmethane such as dimethyltriphenylmethane; and pyrazoline derivatives such as 3-(4-dimethylaminophenyl)-1,5-diphenyl-2-pyrazoline are preferably used. It will be done. The photoconductive composition of the present invention containing a thiopyrylium dye as a sensitizer is obtained by dissolving these thiopyrylium dyes and a photoconductive substance in an organic solvent, and spin-coating this onto a conductive support. It can be coated and dried by a commonly used method such as blade coating, knife coating, reverse roll coating, dip coating, rod bar coating or spray coating, and then used as a photoreceptor, or it can be coated with the above organic solvent solution using a mini spray device, etc. Particles are produced using this method, and the particles are used as a dispersion liquid in an insulating liquid for photoelectrophoresis. Conductive supports include paper; aluminum-paper laminates; metal foils such as aluminum foil and zinc foil; metal plates such as aluminum, copper, zinc, brass and galvanized plates; paper or cellulose acetate, polystyrene, etc. These include ordinary photographic film bases with metals such as chrome, silver, nickel, and aluminum deposited on them. Preferably, paper, cellulose acetate, polyethylene terephthalate, etc., on which a metal such as chromium, silver, nickel, aluminum, or indium oxide is vapor-deposited, is used. Volatile hydrocarbon solvents with a boiling point of 200°C or lower are used as organic solvents, especially dichloromethane,
Preferred are halogenated hydrocarbons having 1 to 3 carbon atoms, such as chloroform, dichloroethane, tetrachloroethane, dichloropropane or trichloroethane. Various other solvents used in coating compositions, such as aromatic hydrocarbons such as chlorobenzene, toluene, xylene or benzene, ketones such as acetone or 2-butanone, ethers such as tetrahydrofuran, and methylene chloride, and mixtures of the above solvents may also be used. Available for use. The solvent is added in an amount of 1 to 100 g, preferably 5 to 20 g, per gram of the total amount of dye, photoconductive material and other additives. The amount of the sensitizer used in the present invention is 0.0001 to 30 parts by weight, preferably 0.001 to 10 parts by weight, per 100 parts by weight of the photoconductive substance. In particular, as a mode of use of the composition of the present invention, it is preferable to incorporate a sensitizer into particles used for photoelectrophoresis. When performing color copying by photoelectrophoresis using these particles, images with excellent three-color separation can be obtained. Particles used in the photoelectrophoresis method are produced from a solution consisting of a photoconductive substance such as poly-N-vinylcarbazole and the sensitizer of the present invention using a mini-spray apparatus. These particles further contain insulating liquids containing saturated hydrocarbons such as decane, dodecane, octane, paraffin, and isooctane, preferably long-chain alkyls such as Isopar E, Isopar H, and Isopar G (manufactured by Etsuo Kagaku Co., Ltd., trade name). It is dispersed in hydrocarbon to form a dispersion liquid, which is used for photoelectrophoresis. Isopar E, Isopar H, and Isopar G contain 99.9, 99.3, and 99.8% by weight of saturated hydrocarbons, respectively, and 0.05, 0.2, and 0.2% by weight of aromatic hydrocarbons, respectively.
However, Isopar H contains 0.5% by weight or less of olefin. The boiling point of each is 115℃~142
℃, 174℃ to 189℃ and 158℃ to 177℃. The amount of particles in the dispersion is between 0.5 and 10% by weight, preferably between 1 and 3% by weight, based on the dispersion. The photoelectrophoresis method and its apparatus are described in Japanese Patent Publication No. 1983-20640. Color photoelectrophoretic electrophotographic photosensitive particles containing the sensitizer of the present invention are different from those made using known thiopyrylium dyes, and can improve color separation from blue-sensitive yellow particles. For example, if cyan particles containing the compound () or () as a sensitizing dye in the red region are mixed with yellow and magenta particles to perform color photoelectrophoresis electrophotography of the three-color mixed particles, good color separation is achieved without color mixing with yellow particles. Give a statue. Magenta particles containing compound () or () as a sensitizing dye in the green region also provide images with good color separation without being mixed with yellow particles. The novel thiopyrylium dyes (), (), () and () having a 2,6-di-t-butylthiopyrylium nucleus used in the present invention can also be used in photoconductors, especially poly-N-vinylcarbazole, thiopyrylium, etc. When used as a sensitizer for organic photoconductive substances such as lylamine and triarylmethane, conventional
It has been found that thiopyrylium dyes with -diphenylthiopyrylium nuclei provide photoconductors with higher sensitivity. To give some specific examples, the novel thiopyrylium dyes ('), ('), (') and (') of the present invention can be used as the conventional thiopyrylium dyes (),
(), () and () give a more sensitive photoconductor. The reason for this is not yet clear, but one of the reasons seems to be that the t-butyl substituent of the compounds (), (), (), and () increases the compatibility with the organic photoconductor. Necessary additives can be appropriately added to the photoconductive layer and particles to improve the properties of the photoconductive layer and particles. For example, an electrically insulating binder component can also be present in the photoconductive compositions of the present invention. Preferred binders used in making the photoconductive compositions of the present invention are film-forming, hydrophobic polymeric binders with fairly high dielectric strength and good electrical insulation. Representative examples of such substances are as follows; natural resins such as vinyl resins, gelatin, cellulose ester derivatives, and cellulose nitrate; polycondensates including polyesters and polycarbonates; silicone resins; styrene-alkyd resins alkyd resins, including paraffin; and various mineral waxes; etc. Examples of specific polymeric materials useful as binders are described in Research Pisclosure, Volume 109, pages 61-67 under the heading "Electrographic Elements, Materials and Methods." Generally, the amount of binder present in the photoconductive compositions of the present invention can vary. Typically, useful amounts of binder are from about 10 to about 100%, based on the total amount of the photoconductive material and binder mixture.
Within the range of 90% by weight. When producing photoconductive particles, a charge control agent,
Dispersion stabilizers may also be added. In particular, a copolymer of lauryl methacrylate and styrene (copolymerization ratio of 4 to 2:
1) or a copolymer of 2-ethylhexyl methacrylate and styrene (copolymerization ratio 4:2-1)
etc. are advantageously used. In addition, in order to improve flexibility and strength, plasticizers such as chlorinated diphenyl, dimethyl phthalate, and epoxy resin (trade name Epicoat) are added to 100 parts by weight of the photoconductive material.
It is also possible to add up to 60 parts by weight, preferably from 10 to 40 parts by weight. The coating thickness of the photoconductive composition of this invention on a suitable support can vary widely. Usually about 10
If the coating is applied within the range of 30 microns (before drying), there is no problem in carrying out the present invention. A preferred range of coating thickness before drying has been found to be within the range of about 50 microns to about 150 microns. However, useful results can be obtained outside this range. The dry thickness of this coating may range from about 2 microns to about 50 microns. However, beneficial results can be obtained with dried coating thicknesses between about 1 and about 200 microns. Figures 1, 2, 3 and 4 show novel thiopyrylium dyes [('), ('),
(') and (')] are respectively used as spectral sensitizers for poly-N-vinylcarbazole, and Figures 5, 6, 7, and 8 show conventional thiopyrylium dyes [ (),
(), () and ()] are respectively poly-N-
This is a spectral sensitivity spectrum when vinyl carbazole is used as a spectral sensitizer. As is clear from comparing Figures 1, 2, 3, and 4 with Figures 5, 6, 7, and 8, respectively, the new thiopyrylium dye is present at the 2 and 6 positions of the thiopyran ring. Because it has a t-butyl group, unlike conventional dyes with aryl groups, there is no sub-absorption near 400 nm, and the photoconductive composition using this new thiopyrylium dye as a spectral sensitizer can be used in the blue region of the visible range, especially at 400 nm. Not sensitive to light of ~450 nm. Next, production examples and examples of a thiopyrylium dye, which is a sensitizer of the present invention, will be shown. Production example 1 2,6-di-t-butyl-4-(2,6-di-
t-Butyl-4H-thiopyran-4-ylidenemethyl)-thiopyrylium perchlorate (compound') 200 mg of 2,6-di-t-butyl-4-methyl-thiopyrylium perchlorate and 2,6-di -t
-Butyl-4-methylthio-thiopyrylium iodide (230 mg) was heated and stirred in 1 ml of acetic anhydride at 100°C for 30 minutes. After cooling, the crystals were filtered and recrystallized from ethyl acetate. Yield 135mg Melting point 195-198℃ Elemental analysis value Calculated value as C ₂₇ H ₄₁ S ₂ ClO ₄ C=
61.28%, H = 7.81%, S = 12.11% Measured value C = 60.99%, H = 7.85%, S = 12.40% Infrared absorption spectrum (wave number cm ^-1 ) 1567,
1480, 1090 nuclear magnetic resonance spectrum (chemical shift, unit ppm)
Trimethylsilane standard 24℃ in heavy acetone
1.53, 7.81, 8.49, each a single line with an area ratio of 36:
The ratio was 4:1. Ultraviolet, visible absorption spectrum (wavelength nm) (ε)
573 (72000), 536 (23700) in acetonitrile,
360 (6400), 295 (17700), 249 (15600) (ε is the extinction coefficient.) Production example 2 2,6-di-t-butyl-4-[3-(2,6-
Di-tert-butyl-4H-thiopyran-4-ylidene)propan-1-yl]-thiopyrylium perchlorate (compound') 2,6-di-tert-butyl-4-methyl-thiopyrylium perchlorate A mixture of 0.2 g of Lato and 0.15 g of diphenylformamidine was heated at 165°C in a test tube for 50 minutes.
After heating for 165 minutes, add 0.2 g of 2,6-di-t-butyl-4-methyl-thiopyrylium perchlorate, 0.2 g of sodium acetate and 1 ml of acetic anhydride.
After heating at ℃ for 5 minutes, it was allowed to cool. Diethyl ether was added, the crystals were filtered, washed with water, dried, and recrystallized from ethyl acetate to obtain 0.128 g of crystals.
Yield 36% Melting point 226-227℃ Elemental analysis values Calculated as C ₂₉ H ₄₃ S ₂ ClO ₄ C = 62.73%, H = 7.81%, S = 11.55%,
Actual value C = 62.61%, H = 7.79%, S = 11.09% Infrared absorption spectrum (wave number cm ^-1 ) 1500,
1272, 1175, 730 Nuclear magnetic resonance spectrum (chemical shift, unit ppm)
Trimethylsilane standard 24℃ in heavy acetone
1.49 (single line), 6.61 (double line), 7.85 (single line),
8.82 (triple line) area ratio is 36:2:4:
It was 1. Ultraviolet, visible absorption spectrum (wavelength nm) (ε)
694 (214000), 645 (74900) in acetonitrile,
380 (2700), 313 (12700), 232 (11100) Production example 3 2,6-di-t-butyl-4-(4-diethylaminophenyl)-thiopyrylium perchlorate (compound') Under argon stream A solution of 0.206 g of 2,6-di-t-butyl-4H-thiopyran-4-one in 30 ml of diethyl ether was cooled to 0°C, and a tetrahydrofuran solution containing 2 mmole of 4-diethylaminophenylmagnesium bromide was added. 4ml was added dropwise over 30 minutes. After the completion of the dropwise addition, the reaction solution was stirred at room temperature for one hour, and the reaction solution was poured into 100 ml of a 2% aqueous perchloric acid solution, and the resulting crystals were filtered, washed with water, and dried. Recrystallized from ethyl acetate. Yield 0.327mg Needle-shaped crystals Melting point 217-218℃ Elemental analysis value Calculated value as C ₂₃ H ₃₄ NSClO ₄ C=
60.57%, H = 7.51%, N = 3.07%, S = 7.03% Measured value C = 60.59%, H = 7.58%, N = 3.05%,
S=7.12% Infrared absorption spectrum (wavenumber cm ^-1 ) 1560,
1275, 1213, 1090 nuclear magnetic resonance spectrum (chemical shift, unit ppm)
Trimethylsilane standard in deuterated chloroform (S, d, t, and q in the box are singlets,
Represents a doublet, triplet, or quartet, the number before H represents the area ratio, and J represents the coupling constant (in hertz) 1.28 (t, 6H, J = 7.08), 1.60 (S, 18H),
3.56 (q, 4H, J=7.08), 6.93 (d, 2H, J=
9.28), 8.06 (d, 2H, J = 9.28), 8.34 (S,
2H) Ultraviolet/visible spectrum (wavelength nm) (ε) in acetonitrile 532 (62200), 288 (11300), 259
(7700) Production Example 4 2,6-di-t-butyl-4-(4-diethylaminostyryl)thiopyrylium perchlorate (compound') 2,6-di-t-butyl-4-methyl-thiopyryl 0.496 g of lium perchlorate and 0.26 g of 4-diethylaminobenzaldehyde were heated in 1.5 ml of acetic anhydride at 95°C for 7 minutes. The mixture was allowed to cool, diethyl ether was added to precipitate crystals, filtered, and recrystallized from ethanol. Yield 0.404g Needle-shaped crystals Melting point 218-219℃ Elemental analysis value Calculated value as C ₂₅ H ₃₆ NSO ₄ Cl C =
62.28%, H = 7.52%, N = 2.90%, S = 6.65% Measured value C = 62.26%, H = 7.55%, N = 3.05%,
S=6.74% Infrared absorption spectrum (wavenumber cm ^-1 ) 1552,
1515, 1183, 1152 Nuclear magnetic resonance spectrum (chemical shift, unit ppm)
Trimethylsilane standard in deuterated chloroform
1.24 (t, 6H, J=7.08), 1.55 (S, 18H),
3.49 (q, 4H, J=7.08), 6.74 (d, 2H, J=
9.28), 7.85 (d, 2H, J=9.28), 7.31 (d,
1H, J=15.1), 8.13(d, 1H, J=15.1),
8.12 (S, 2H) Ultraviolet/visible absorption spectrum (wavelength nm) (ε)
622 (82900), 350 (6100), 310 in acetonitrile
(11600) Production example 5 2,6-di-t-butyl-4-[3-(2,6-
Di-tert-butyl-4H-thiopyran-4-ylidene)-2-phenylpropen-1-yl]thiopyrylium tetrafluoroborate 2,6-dimethyl-4-methylthiopyrylium tetrafluoroborate 310 mg and benzoyl chloride 80 mg and was heated in 10 ml of pyridine on an oil bath at 120° C. for 30 minutes. After cooling, 50 ml of diethyl ether was added to precipitate crystals, which were recrystallized from ethyl acetate. Yield 30mg. Melting point 249-250℃. Assuming elemental analysis value C ₃₅ H ₄₇ S ₂ BF ₄ Calculated value C = 67.93%, H = 7.66%, S = 10.36
% Measured value C=67.76%, H=7.65%, S=10.09
% Infrared absorption spectrum (wave number cm ^-1 ) 1588, 1467, 1413, 1233, 1180, 1080 Ultraviolet/visible absorption spectrum (wavelength nm) (ε) In acetonitrile 705 (112000) 360 (15600) 308 (10200) Production example 6 2,6-di-t-butyl-4-[3-(2,6-
di-t-butyl-4H-thiopyran-4-ylidene)-2-(4-bromophenyl)propene-
1-yl]thiopyrylium tetrafluoroborate 310 mg of 2,6-dimethyl-4-methylthiopyrylium tetrafluoroborate and 110 mg of p-bromobenzoyl chloride were heated in 10 ml of pyridine on an oil bath at 120°C for 40 minutes. After cooling, diethyl ether
50 ml was added to precipitate crystals, which were recrystallized from ethyl acetate. Yield 20mg. Melting point 247-248℃. Elemental analysis value C ₃₅ H ₄₆ S ₂ BrBF ₄ Calculated value C = 60.29%, H = 6.64%, S = 9.19
%. Measured values C=60.01%, H=9.34%, S=9.34
%. Infrared absorption spectrum (wave number cm ^-1 ) 1588, 1460, 1413, 1235, 1190, 1080 Ultraviolet/visible absorption spectrum (wavelength nm) (ε) In acetonitrile 706 (100000) 365 (18900) 308 (12900) Production example 7 2 ,6-di-t-butyl-4-(4-dimethylaminostyryl)thiopyrylium perchlorate 319 mg of 2,6-di-t-butyl-4-methylthiopyrylium perchlorate and 150 mg of 4-dimethylaminobenzaldehyde were combined into 5 mg. in acetic anhydride
Heated on a 100°C oil bath for 40 minutes. After cooling, 100 ml of diethyl ether was added to precipitate crystals, which were then recrystallized from ethanol. Yield 210mg. Melting point 240℃. Elemental analysis value C ₂₃ H ₃₂ NSClO ₄ Calculated value C = 60.85%, H = 7.10%, N = 3.09
%. Measured values C=60.91%, H=7.05%, N=3.22
%. Infrared absorption spectrum (wave number cm ^-1 ) 1552, 1528, 1187, 1160, 1120. Ultraviolet/visible absorption spectrum (wavelength nm) (ε) In acetonitrile 610 (68100) 310 (11800) Example 1 1 g of poly-N-vinylcarbazole and Production Example 1
3 mg of the compound (') obtained above was dissolved in 10 g of 1,2-dichloroethane and coated on a polyester film coated with aluminum using a No. 16 rod bar. A photoreceptor was prepared by drying at 55°C for one day. This photoreceptor was charged to +450V by corona discharge of +6kV using a commercially available device, and then the surface was irradiated with light using a tungsten lamp at an illuminance of 4.5 lux, and its surface potential was increased.
The exposure amount was obtained by determining the time (seconds) it took for the voltage to reach 225V. The result was E1/2 = 67 lux seconds. Example 2 and Comparative Examples 1 to 2 Compounds (') shown in Table 1 below were used in place of the compound (') of Production Example 1 used in Example 1,
A photoreceptor was prepared according to the same photoreceptor preparation method as in Example 1 except that (V) and () were used respectively, and the same measurements as in Example 1 were carried out on these photoreceptors to obtain the results shown in Table 1. Ta. Comparative Examples 1 and 2 using known thiopyrylium dyes () and () are controls for comparison with Examples 1 and 2.

[Table] Example 3 1 g of poly-N-vinylcarbazole and 3 mg of compound (') were dissolved in 10 g of 1,2-dichloroethane, and No. 1 was placed on a polyester film deposited with aluminum.
It was applied using a No. 16 rod bar. A photoreceptor was prepared by drying at 55°C for one day. This photoreceptor was charged to +450V by corona discharge of +6kV using a commercially available device, and then the surface was irradiated with light using a tungsten lamp at an illumination intensity of 4.5 lux, and its surface potential was increased.
The exposure amount was obtained by determining the time (seconds) it took for the voltage to reach 225V. The result was E1/2 = 47 lux seconds. Example 4 and Comparative Examples 3 to 4 Photoreceptors were prepared in the same manner as in Example 3, except that compounds ('), (), and () shown in Table 2 below were used instead of compound (') in Example 3. Photoreceptors were prepared according to the method, and the same measurements as in the examples were performed on these photoreceptors to obtain the results shown in Table 2. Comparative Examples using known thiopyrylium dyes () and () are controls for comparison with Examples 3 and 4.

[Table] Example 5 Poly-N-vinylcarbazole 5g, dye 150
Particles were produced from a solution of 250 g of dichloromethane and 250 g of dichloromethane using a mini spray device (Yamato Scientific Manufacturing). However, the following three types of dyes were used to obtain three-colored particles. Cyan particles 2,6-di-t-butyl-4-[3
-(2,6-di-t-butyl-4H-thiopyran-4-ylidene)propen-1-yl]thiopyrylium perchlorate (compound) Magenta particles Rhodamine B Yellow particles Thioflavin T and a copolymer of lauryl methacrylate and styrene (copolymerization ratio 4:1, viscosity 1.52, specific gravity
0.86) 250 ml of Isopar H (manufactured by Etsuo Chemical Co., Ltd., boiling point 174° to 189°C) containing 1 g of insulation containing 99.3% by weight of saturated hydrocarbons, 0.2% by weight of aromatic hydrocarbons and not more than 0.5% by weight of olefins. A dispersion liquid for photoelectrophoresis was prepared by dispersing 2% by weight in a neutral liquid). To obtain an image using this dispersion, a photoelectrophoretic imaging device shown in FIG. 9 is used. In the drawing, 1 is a transparent electrode, which is
It consists of an optically transparent glass layer 2 coated with a thin optically transparent layer 3 of tin oxide, commercially available as NESA Glass (trade name). 4 is a dispersion liquid for photoelectrophoresis, and 5 is a blocking electrode, which is connected to a power source 6 through a switch 7. 8 is a color slide, 9 is a blocking electrode material layer, and 10 is a conductive central core. Electrode 5 is made in the form of a roller with an electrically conductive central core connected to electrode 6. The roller has a diameter of approximately 6.5 cm and has a diameter of approximately 2
It is moved across the surface of the plate at a speed of cm/sec. Arrows indicate the direction of light. It is exposed to light with an intensity of 20,000 lux on a NESA glass surface. The magnitude of the applied voltage is 1K volts. The image thus obtained has a color balance and density that matches the original, and is particularly good in trichromatic separation. Embodiments of the present invention are shown below. (1) General formula (However, A in the formula is

【formula】

【formula】

[expression] or

[Formula], Z represents an anion, and X represents hydrogen, aryl, substituted aryl or alkyl group.
Further, R ¹ and R ² represent the same or different alkyl groups. ) A photoconductive composition comprising a photoconductive substance containing a thiopyrylium dye represented by: as a sensitizer. (2) General formula (However, A in the formula is

【formula】

【formula】

[expression] or

[Formula] is represented, and Z represents an anion. ) A method for producing a photoconductive composition, which comprises dissolving a thiopyrylium dye represented by the following formula and a photoconductive substance in an organic solvent. (3) A photoreceptor characterized in that the photoconductive composition of embodiment (1) is applied onto a conductive support and dried. (4) A dispersion liquid for photoelectrophoresis, characterized in that particles are produced from the photoconductive composition of embodiment (1) and the particles are dispersed in an insulating liquid. (5) Thiopyrylium dye is 2,6-di-t-butyl-4-(2,6-di-t-butyl-4H-thiopyran-4-ylidenemethyl)thiopyrylium salt (compound) (Z represents an anion.) The photoconductive composition according to embodiment (1). (6) Thiopyrylium dye is 2,6-di-t-butyl-4-[3-(2,6
-di-t-butyl-4H-thiopyran-4-ylidene)propen-1-yl]thiopyrylium salt (compound-a) (Z represents an anion) The photoconductive composition according to embodiment (1). (7) Thiopyrylium dye is 2,6-di-t-butyl-4-(4-diethylaminophenyl)thiopyrylium salt (compound-a) (Z represents an anion) The photoconductive composition according to embodiment (1). (8) Thiopyrylium dye is 2,6-di-t-butyl-4-(4-diethylaminostyryl) thiopyrylium salt (compound-a) (Z represents an anion) The photoconductive composition according to embodiment (1). (9) Thiopyrylium dye is 2,6-di-t-butyl-4-[3-(2,6
-di-t-butyl-4H-thiopyran-4-ylidene)-2-phenylpropen-1-yl]
Thiopyrylium salt (compound-b) The photoconductive composition according to embodiment (1). (10) Thiopyrylium dye is 2,6-di-t-butyl-4-[3-(2,6
-di-t-butyl-4H-thiopyran-4-ylidene)-2-(4-bromophenyl)propen-1-yl]thiopyrylium salt (compound-
c) The photoconductive composition according to embodiment (1). (11) The thiopyrylium dye is 2,6-di-t-butyl-4-(4-dimethylaminostyryl) thiopyrylium salt (compound-b) The photoconductive composition according to embodiment (1). (12) The photoconductive composition according to embodiment (1), wherein Z is an anion of a strong acid with a pKa of 5 or less. (13) Z is chloride ion, bromide ion,
The photoconductive composition of embodiment (1), wherein the anion is selected from perchlorate ion, tetrafluoroborate ion, p-toluenesulfonate ion, and trifluoroacetate ion. (14) The photoconductive composition according to embodiment (1), which uses at least one photoconductive substance selected from poly-N-vinylcarbazole, triarylamine, polyarylmethane, and pyrazoline derivatives. (15) 2,6-di-t-butyl-4-(2,6-
di-t-butyl-4H-thiopyran-4-ylidenemethyl)thiopyrylium salt or 2,6-
Embodiment using tricolor mixed particles obtained by mixing magenta particles containing di-t-butyl-4-(4-diethylaminophenyl) thiopyrylium salt as a sensitizing dye in the green region with cyan particles and yellow particles Dispersion of (4). (16) 2,6-di-t-butyl-4-[3-(2,
6-di-t-butyl-4H-thiopyran-4-
ylidene)-propen-1-yl]thiopyrylium salt 2,6-di-t-butyl-4-[3-
(2,6-di-t-butyl-4H-thiopyran-
4-ylidene)-2-phenylpropene-1-
yl]thiopyrylium salt, 2,6-di-t-butyl-4-[3-(2,6-di-t-butyl-
4H-thiopyran-4-ylidene)-2-(4-
Bromophenyl)propen-1-yl]thiopyrylium salt, 2,6-di-t-butyl-4-
(4-dimethylaminostyryl)thiopyrylium salt or 2,6-di-t-butyl-4-(4
-Diethylaminostyryl) thiopyrylium salt as a sensitizing dye in the red region, the dispersion according to embodiment (4), which uses trichromatic mixed particles obtained by mixing cyan particles with yellow particles and magenta particles.

[Brief explanation of the drawing]

Figures 1, 2, 3 and 4 are spectral sensitivity spectra of a photoconductive composition made of poly-N-vinylcarbazole containing a thiopyrylium dye of the present invention; FIG. 8 shows a spectral sensitivity spectrum when a conventional thiopyrylium dye is used. FIG. 9 shows a photoelectrophoretic imaging device.

Claims (1)

[Claims] 1. General formula (However, in the formula, A represents [formula] [formula] [formula] or [formula], Z represents an anion, and X represents hydrogen, aryl,
Represents a substituted aryl or alkyl group. Also
R ¹ and R ² represent the same or different alkyl groups. ) A photoconductive composition comprising a photoconductive substance containing a thiopyrylium dye represented by: as a sensitizer.