DE1909742A1 - Process for the production of an electrophotographic recording material - Google Patents

Description

Process for the production of an electrophotographic recording material

The invention concerns? · A method of making a electrophotographic recording material in which on an electrically conductive layer support, a photoconductive layer is produced from an organic photoconductor, a dye and a hydrophobic polymer, the Photoconductor through a two-phase, heterogeneous system of dye and polymer, the phases of which are approximately 2500 times magnification visible Bind, being sensitized.

Processes for making electrophotographic recording materials and the use thereof for making copies are known and are described, for example, in U.S. Patents 2,221,776; 2 277 2 297 013i 69I; 2,357,809; 2,551,582; 2,825 81H; 2,833 6M8; 3,220,324; 3 220 831 and 3 * 220 833. In the known processes, electrophotographic imaging materials are used as an insulating, photoconductive layer,

909836/134

BATH ORIGINAL

those with imagewise exposure to electromagnetic radiation provide a latent, electrostatic charge image. That on The electrostatic charge image obtained in this way can be further processed or developed in the most varied of ways to form a permanent copy.

The known electrophotographic recording materials usually consist of a layer support and one here. on applied photoconductive layer from in one: "resin, shaped binder dispersed photoconductor particles. Of the

The support can consist of a film that has been coated with a layer of a conductive material, or of a chemical or other conductive material. It is also known that the sensitivity of the photoconductive layers and / or to increase their spectral response by incorporating sensitizing substances into the photoconductive layer. Such sensitizing additives are known, for example, from US Patents 3,250,615; 3 I ¹ U.770 and 2,987,395 The Mec The hanism of such sensitization has not yet been fully clarified. The importance or importance of such awareness effects is indicated by. the intensive research in the field of photosensitization of photoconductors of electrophotographic recording materials.

eomft / mf. "" ν? _BAD0RUälNAt

1Π09742

■ Usually, the degree of change in electrophotographic properties is determined by the way in which the electrophotographic recording materials are used. Applies, for example, for copying · documentary evidence that the spectral presence _t-speaking capacity of the photoconductor so supposed to be that these are able to reproduce a wide color range. In many cases, the electrophotographic recording materials must also meet other requirements, for example they must have a high surface potential and the charge drop must be small in the dark. It is also desirable that the electrophotographic recording material have high electrical sensitivity, only a low potential after exposure, and that the material is also fatigue-resistant.

It is known that photoconductors by adding certain Let dyes sensitize and that by such Sensibilisieruhg the desired flexibility in the design achieve electrophotographic recording materials leaves.

It has been shown, however, that to date there have been no sensitization additives are known which practically all to improve essential characteristics of electrophotographic recording materials in the desired manner capital. For example, it has also been shown that by adding common dyes to phptoconductive layers only a limited improvement in the essential properties of electrophotography rather than recording materials can achieve. ,. ";".

There has therefore been no lack of attempts to establish the properties to improve electrophotographic recording materials, In particular, their sensitivities, both

BATHROOM GINAL

909836/1341

■ their "shoulder sensitivity as well as their sensitivities in the sagging area of the sensitivity curves" · Furthermore, there has not been a lack of attempts _s . Reproduction or · reproduction of large areas % u improve and remove? The electrophotographic sensitivity of the teaching equipment _s so improved that they are suitable for a ._-..- positive as well as for a negative electrostatic charge « @ nd @ t can /

A significant advance in the development of highly sensitive electrophotographs is rather recording materials through the development of electrophotographic recording materials rials. with so-called photo-conductive aggregate sy stones succeeded ^ as you can see from the Belgian patent specification 705 11?

scanned- have become ₀ s © wi @ aws &<at belgischen- Paten.tsch.r'i £ t ■ ''"70S. 11Su - -----

The object of the invention was "a process for production". eini elektrophotographlsGtera Aufseichntmggmat.erials "anssu -..- '-.- give _s -which © © di © H © s? stallimg further ¥ @ rb®ssert © r and Ins- - ■ -, _ special'nochempfinailchex ³ © ^ elitrophotographic recording materials. ■ - "': .-" ■ -

The invention had the Erkeniitöi © sügrün AEE _s that die.Emp "flndlichkeit elektrophotögraphisehsr Aufseiehnungsmaterialien the 'type ,, the -beispielsvfeise from the -belgischen patent is known 705,117, still vielter improve / _s can wsnn such elektrophotographlsehe Auf'zeichnungsmateriälleh. treated once more or several times with a solution © ines / sensitizing dye, * d »h. when the known. Elektrophötographen recording materials are "once" or several times coated with a solution of a sensitive dye.

909 8 36 / 13-4 1

909742

The subject of the invention is thus a process. " % ur production of an electrophotographisohea Äufäeichnwgsmaterial-, in which on an electrically conductive ^ «. Substrate _s a dye and a hydrophobic polymer is formed a photoconductive layer of an organic photoconductor, wherein said photoconductor äixroh a from & wei phases existing ^ heterogeneous system of dye and polymer _a whose phases at about 25OO-fan magnification are visible _s sansibilisiert ,, which is characterized. that on the photoconductive layer of the recording material. solvent coating a solution of a sensitizing dye in a volatile hydrocarbon and the solvent evaporated _s is said "process optionally sin ~ or more times is repeated"""-;. -

Preferably i? © r ^a applies, one for? "This" .possible sensitization a dye-of the class " ₉ or sur- production of the photoconductive layer of the -sighting material was used or -be used 'Icaaa"

As a precaution ¥ @ rwenast one aur- Erseugmig ubtp photoconductive layer and sui ³ . After sensitization according to the invention, known pyrylium dyes, and partly in particular Pyrylium- _S: Selenapyrylium- and / or Thiapyryllumfärbs.to ffsalse »

The preparation of the photoconductive layers of the photographic recording material of the invention is based on the Belgian method. Patent 7Q5 117 known. The two-phase heterogeneous system from sensibili _s ^ i © = · · 'rendem dye and ■ hydrophobsiö polymer takes öafeel ®n ~ - j ter conditions which for. Education -a recognizable®!?. Two «phase system lead, -i ^ elohea" sis Radiationafeaoimfeions = ·. ' maximum, - which differs from the ..Strahluhgsm'asiimoi ctes dye, which. dissolved in the polymer iyfc »

i 3 t / 1 * 3 4-f

As is apparent 117. Belgian Patent _JOS.,: Blank "Siph the photoconductive layers of such On = zeichnungsmateriälien in different ways generating Thus, it is possible for instance ^ a solution of the components of the photoconductive unit system in the form of a layer in. Conventional manner to a conventional To apply layer support and to create the heterogeneous system consisting of two phases in situ in the layer formed »One method of transferring a homogeneous layer of dye and polymer into the heterogeneous system consists of the layer created. Lean time the vapors of a solvent . suspend can, WEL 'EHES dl © layer to soften ,, wherein the dye is caused to migrate and forms aggregates in a two ~ Phase.n · = system at a temperature of for example 21 ⁰ C;. an effective formation of a successful consist of two phases = · the _s heterogeneous system sehoa with an action lasting 2 minutes de r solvent "fumes other hand, it is also possible in · = ■" play to generate the heterogeneous system characterized _s that removal of the solvent, the cher in Übli »way applied from a solution photoconductive Sehieht geheram ¹ -.! or behindergA Furthermore, ^es: For example, it is also possible to dip the homogeneous layer in a solvent! to immerse or sm? B & reltmig the photoconductive layer a .Lösungsmittelgemiscb to use _s which is a. _: - high-boiling solvent contains _s . which during drying of the layer ^ process in this .verbleibt, A further advantageous method for producing such aggregates aufwei- V:. sender j, ph'o to le it viable layers is _s for the Preparation of the layers veww ended Besehichtungsniassen ■■ "■ '■. Strong shear forces are used and the coating maeses pretreated in this way are to be applied in the usual way, to a layer ■ carrier, to dry in the usual way ⁵ titsa ■ -''_

It has been shown _s - άε & sich di.® - InsItM erssiagtep _s hetero-; ■ .gsnen phases erkemiea let _s' when ίάεμ the layers at;. "" ■■ -; ■ :.

i 0 g Il 8 / ta 4 ί -. '\.; ^V BAD ORIGINAL "

about 25OCHfold? VesvgFoSenasg betiraehtstp although the layer t @ si fe © i aösriisler observation nit d © m Awg © © has VgygrdS ^ fftss & g the appearance is practically optical. felar © x. Layer © »hab © n _a The aggregates always end Layera can, however, also @ isi @ visible heterogeneity s © igem ₀ Ia typicalfr way b © sits © a di © Aggregate © d © r dislcoEtimisierliehta Phas © predominantly © in © Groß © von about 0.1 "to 25 Mifeoaa .- ■" .-

The process d © F Erfinimig © rmöglicht "thus dl © Hers part in

iotögfsphisches'

whereby

dam to day © enters _& w © aa cally on in ©

As' special ©! Fs yos "t © ilhaft @ seasibiiisi @ f @ ad @ dyestuff® to etzengmig d & t ph © toconductive © m layers as well as- to

Here in

R ₉ R ₆ R ₈ R uad R each represent a hydrogen atom or a

aliphatic radical having preferably 1 to 15 carbon atoms' or one

© in sulfurized oxygen or selenium atom and '

an anion. ■ "" -

0 0-8-36 / 1 3 A 1-

BATH

In detail, R ¹ , R ² , R ³ , R * and R ^{5 can represent,} for example: alkyl radicals with 1 to 15 carbon atoms, for example methyl, ethyl, propyl, isopropyl, butyl ^, tert «, * Butyl ^, amyl, isoamyl, hexyl, octyl, nonyl or dodecyl radicals; or styryl, methoxystyryl, diethoxystyryl, dimethylaminostyryl, i-butyl-4-p-dimethylaminophenyl-i, 3-butadienyl or β-ethyl-4-dimethylaminostyryl radicals; or alkoxy radicals with preferably 1 to 15 carbon atoms, for example methoxy, ethoxy, propoxy, butoxy, amyloxy, hexoxy or octoxy radicals or alkenyl radicals with 1 to 15 carbon atoms, ζ , e.g. vinyl radicals W or optionally substituted aryl radicals, e.g. B, the phenyl. or naphthyl series, preferably having 6 to 14 carbon atoms, e.g. B. phenyl, 4-diphenyl or alkylphenyl, e.g. B. 4-ethylphenyl or 4-propylphenyl radicals, or alkoxyphenyl radicals, for example 4-xthoxyphenyl, 4-methoxyphenyl, 4-amyloxyphenyl, 2-hexoxyphenyl, 2-methoxyphenyl or 3,4-dimethoxyphenyl radicals, or β-hydroxyalkyi radicals , e.g. B «2-Hydroxyäthoxyphenyl- or 3-Hydroxyälihoxyphenylreste, or 4-Hydroxyphenylreste or Halophenylreste, ζ. B. 2,4-dichloxophenyl, 3 ^ 4-dibromophenyl, 4-chlorophenyl, 2,4-dichlorophenyl, or azidqphenyl, nitrophenyl, aminophenyl, e.g. 4-diethylaminophenyl or 4-dimethylaminophenyl, or naphthyl.

'Z can be, for example, a perchlorate, fluoroborate, Iodide, chloride, bromide, sulfate, periodate or p-toluenesulfpnate anion "

Furthermore, R. ¹ and R ² and R ⁴ and R ⁵ together represent the atoms #, which are necessary for a Veryollständigung Arylringest which is ankohdensiert on the pyrylium ring.

J.i λ

Typical ones suitable for practicing the method of the invention Pyryiii / uifArerstoffef sand ^ in the following Table 1 to ^ - together te ^ L It:

9 0 98367

TABELEE

Connecting

number name of the connection

4- (4-bia- (2-chloroethyl jaminopheny1) -2,6-diphenylthiapyrylium perchlorate,

4- (4-Dimethylaminophenyl) -2 , 6-diphenylthia ^ pyrylium perchlorate,

"4- (4-dimethylaminophenyl) -2,6-diphenylthia-

pyrylium fluorobarate,

* 4- (4-dimethylamino-2-methylphenyl) -2,6-diphe-

nylpyrylium perchlorate,

4- (4-Bi3 (2-chloroethyl) aminophenyl) -2- (4-methoxyphenyl) -6-phenylthiapyrylium perchlorate,

4- (4-Dlraethylamlnophenyl) -2,6-diphenylthiapyrylium sulfate,

4- (4-Dimethylaminophenyl) -2,6-diphenylthiapyry.lium-p.-toluenesulfonate,

4- (4-dimethylaminophenyl) -2,6-diphenylpyrylium p-toluenesulfonate,

2- (2,4-Dimethoxy pheny 1) - 4- (4-dimethyl am * »inophenyl) benzo (b) pyrylium perchlorate, 2,6-bis (4-ethylphenyl) -4-C4-dimethylaminophenyl) thiapyrylium perchlorate,

. 4- (4-dimethylaminophenyl) -2- (4-methoxyphenyl) -

6-phenylthiapyrylium perchlorate, 4- (4-Dimethylaminophenyl) -2- (4-ethoxypheiiyl) -6-phenylthiapyrylium perchlorate, 4- (4-dimethylaminophenyl) -2- (4-methoxyphenyl) -6- (4-methylphenyl) pyrylium perchlorate, 4- (4-dimethylaminophenyl) -2,6-diphenylthi} ipyry- = 1 iump er chi or at,

2,4,6-triphenylpyrylium perchlorate, . 4- (4-r-methoxyphenyl) -2,6-diphenylpyrylium per-

chlorate,

4- (2,4-dichlorophenyl) -2,6-diphenylpyrylium per- - chlorate,

4- (3,4-dichlorophenyl) -2,6-diphenylipyrylium perchlorate ^ '^;

2,6-bis (4-methoxyphenyl) -4-phenylpyrylium perohlorate,

909836/1341

20 6- (4-methoxyphenyl) -2,4 - diphenylpyrylium perchlorate,

21 2- (3, ⁱ * -Dichlorophenyl)> 4- (4-methoxyphenyl) -6-phenylpyryllumperchlorate,

22 4- (il-Ainyloxyphenyl) -2,6-bis (4-ethylphenyl) -pyryliümperchlorat,

23 4- (4-Amyloxyphenyl) -2,6-bis (4-methoxyphenyl) -. pyryl perchlorate,.

24 2 ₉ 4 ₃ 6-triphenylpyrylium fluoroborate ₃

25 2,6-bis (4-ethylphenyl) -4- (4-methoxyphenyl) pyrylium perchlorate,

26 2,6-Bl3 (4-ethylphenyl) -4- (4-methoxyphenyl) -pyryllumfluoroborat,

27 6- (3,4-Dläthoxystyryl) -2,4-Diphenylpyrylluinperchlorat,

28 6- (3,4-diethoxy-βxamylstyryl) -2,4-diphenyl- < pyryllum fliioroborate,

29 6- (4-DlmethylamIno-ß-ethylstyryl) -2 _a 4-diphenylpyryllum fluoroborate,

30 6- (l-n-amyl-4-p-dimethylaminophenyl-1,3-butadienyl) -2,4-diphenylpyryllunifluoroborat,

31 6- (4-dimethylaniinostyryl) -2,4 ^ diphenylpyrylium fluoroborate,

32 6- / ~ a-ethyl-ß, 8-bis (dlraethyraminophenyl) yinyleri7-2, ^ - diphenylpyryllum fluoroborate,

33 6- (l-butyl-4-p-dimethylaminophenyl-1,3-butadieriyl) -2,4-diphenylpyrylium fluoroborate,

34 6- (4-Dlmethylaminostyryl) -2,4-dlphenylpyrylium perchlorate,

35 6 - / "ß, ß-Bl3 (4-dimethylamlnophenyl) vinylen_7-2, If-dlphenylpyrylium perchlorate,

36 2,6-Bi3 (4-diraethylaminostyryl) -4-phenyipyry-1lumperchlorate,

37 6-U-methyl-4-dimethylaminostyryl) -2,4-dlphenylpyrylium fluoroborate,

38 6- (l-Ethyl-4-p-dlmethylamlnopheriyl-1,3-butadlenyl) -2,4-dlphenylpyrylium fluoroborate,

39 6- / ~ 0,3-Bi8 (4-difflethylam-inophenyl) vinylen_7-2,5-dlphenylpyryliumfluororpborat, ",

40 6- (l-methyl-4-p-dlmethylaminophenyl-1,3-butadieny1) -2,4-dlphenylpyrylium fluoroborate,

909836/1341, ORiGiNAL inspected

41. 4-X4-Diraethylamlnpp-henyl) -2-, 6-diphenyl- ·

pyrylium perchiorate ;, ".

42 - 2 _y 6-bis (-4-'äthylpheny.l> -4 - phezqrlpyt ^> yliumpeJ? -

chlorate

43. 2,6r bis (4-ethylphenyl) - ¹ l-methdxyphenylthia-

pyrylium fluoroborate,

44 ... 2 _J 4,6-triphenylthiäpyrylium ^{per t} chlorate,

45 4- (4-metho9yphenyl) -2,6-diphenylthlapyrylium perchlorate,

46 6- (4-Methoxyphenyl) -2,4-diphenylthiapyrylivunpercltlorat, ^s

47 2,6-bis (4-methoxyphenyl) -4 ^ phenylthiapyrylium perchlorate, '.

48 ^ "Cej ^ -Mchlorophen
"^; pyryllumperchlGrat,

49 2 ₉ M _t 6
chlorate,

50 2,6-bis (4-ethy! Phenyl) -4-phenylthlapyryliumperehioratj -

51. 4- (4-amyloxyphenyl) -2,6-bis (4-ethylphenyl) -

thiapyryli perchlorate,

52 - 6- (4-dimethylaminostyryl) -2 _J 4-diphenylthla-

pyrylium perchlorate, -

53. 2,4,6-triphenylthiapyrylium fluoroborate;

54 ■ 2,4,6-Trlphenylthiapyryllumsuli'at,

55 · '4- (4-methoxypheriyl) -2,6-diphenylthiapyryliuiii-

fluoroborate ^,.

56 "^; 2,4,6-triphenylthiapyryllum chloride,

57. 2- (4-amyloxyphenyl) -4,6-diphenylthiapyrylium- • ■ 'fluoroboratj

58 4- (4 ^ amyloxyphenyl) ~ 2,6-bis (4-methoxyphenyl) -thlapyryl perchlorate,

59 2 _s 6-bis (4-ethylphenyl) -4- (4-ynethoxyphenyl) - "■" .-. "■ thiapyrylium perchlorate,

βθ '4-aisyl-2,6-bis (4-n-amyloxyphenyl) thiapyry-. ■ / - ■ ", fluoro chloride,"

61 2- / ~ &, ß-bis (4-dimethylaminophenyl) vinylene_7-. \ - 4, S-diphenylthiapyrylium perchlorate,

62 6- (e ^ JCthy 1-4-dimethylamino styryl) -2,4-dipheny 1- ^: - '_; -. ^{thiapyryliumperchlorat;} ; ;.

90 98 36V 1 ^ 3

63 2- (3,4-diethoxy styryl) -4,6-dlphenylthiapyry-

1lumperchlorate,.:

64 2,4,6-trianisylthiapy.rylium perchlorate, 65. ö-ethyl-aj ^ -diphenylpyryllumflüoröborats ·

66 2 ₉ 6-bis (4-ethylphenyi) -4- (4-methoxypiaenyl) thia = pyrylium chloride,

67 6- / ~ β, ß-bis (4-dimethylaminophenyl) vinylene_7 ~ 2,5-dl- (4-ethylphenyl) pyrylium perchlorate, ~

68 2 _i 6-bis (4-amyloxyphenyl) -4- (4-methoxyphenyl) -thiapyryllumperchlorate _s

69 6- (3 _J 4-DIäthoxy-ß-ethylstyryl) -2 _s 4-d ± phenylpyrylium fluoroborate,

70 6- (4-methoxy-ß-ethylstyryl) -2 _s 4-diphenylpyrylium fluoroborate,.

71 2- (4 ~ ethylphenyl) -4,6-diphenylthiapyrylium perchlorate,

72 2,6-Diphenyl-4- (4-methoxyphenyl) thiapyrylium ^ perchlorate

73 2,6-Diphenyl ~ 4- (4-methoxyphenyl) thiapyrylIuin>, - fluoroborate,

74 2,6-bis (4-ethylphenyl) -4- (4-n-amyloxyphenyl) thia-

pyrylium perchlorate 5

75 2,6-bis (4-methoxyphenyl) -4- (4-n-amyloxypbenyl) -thiapyrylium perchlorate,

76 2 _s 4 _s 6-tri (4-methoxyphenyl5 ~ tiiiapyryliumfluoro> boratej · '■■ ".-"".- ■■

77 2 _? 4-diphenyl-6- (3 _s 4-diethoxystyryl) pyrylium perchlorate j

78 4- (4-Dimethylarainophenyl) -2-phenylbenzo (b) -. selenapyryllumperchlorate,

79 2- (2 _J 4-Dlmethoxyphenyl) -4- (4-dlmethylaminophenyl) -benzo (b) selenapyryilumperchloratj

80 4- (4-Dlmethylämlnophenyl) -2 _J 6-dlphenylselenapyryliumperchlorat,

31 4- (4-Dlm.ethylamlnophenyl) -2- (4-ethoxyphenyl) -

6-phenylselenapyryllumperchlorate ₃

82 4- (4-bis (2-chloroätliyl) aminophenyl) -2 _i, 6 _»s dlphenylselenapyryllumperchlorat

83 4- (4-Dlmethylaminophenyl) -2 _J 6-bls (4-ethylphenyDselenapyryllumperchlorat,

90983 "$ / 13A1

84 i »- (4-Dlmethylaniino-2-methylphenyl) -2,6-diphenylselenapyrylium peroxide ₃

85 3- (4-Dimethylaminopheny1) naphtho (2,1-b) selenapyrylium perchlorate _s

86 .4- (4 ^ Dimethylaminostyryl) ~ 2- (4 ~ methoxyphenylbenzo (b) -selenapyrylium perchlorate _s

87 2,6-di- (4-diethylaminophenyl) -4-p.henylselenapyrylium perchlorate, .

88 4- (4-Dimethylaminophenyl) -2 »(4-ethoxyphenyl) -6-phenylthiapyrylinrafluoroborat _e

Pyrylium dye salts are particularly advantageous dyes for generating the aggregates and for resolving following structural formula:

Ζ ^Θ

where mean: - -

C O

R and R each aryl radicals, in particular optionally substituted phenyl or naphthyl radicals;

R represents an arylamino radical or one through an alkyl amino radical substituted aryl radical.

X and Z have the meanings already given.

R and R can thus be, for example, aryl radicals, wel-. before optionally with one or more alkyl radicals 1 to 6 carbon atoms or one or more alkoxy radicals may be substituted with 1 to 6 carbon atoms.

909a-3S J Ti41 _BAD

_ 11} "

7th
If R. has the meaning of an aryl radical substituted by an alkylamino radical, the alkyl groups of the alkylamino radicals can, for example, have Γ to β carbon atoms. The alky! Aminoaryl radicals may optionally also be halogenated ₁ ie. the alkyl group © »the radical® -can be substituted by one © der-several halogen atoms s @ in ₀ \,. ■ ■

Instead of the pyrylium dyes, other conventionally known ₃ spectral sensitizing dyes can be used for generation of the photoconductive layer, and are used to Naehsensibilisierung.

Hydrophobic polymers having particularly suitable for Erzeugung.der aggregates photoconductive layer eigneri _s particular Polydiary! Alkanes such. B. Polycarbonates and polythiocarbonates, polyvinyl ethers, polyesters, poly-α-olefins, phenolic resins and the like. Typical polymers suitable for producing the photoconductive layer of the electrophotographic recording device are the polymers listed in Table 2 below.

TABEL

No. Hydrophobic Polymers

1 polystyrene,

2 polyvinyl toluene,

3 polyvinyl anisole

4 polychlorostyrene,

5 'poly-o-methylstyrenej

6 polyacenaphthalene,

7 poly (vinyl isobutyl ether),

8 poly (vinyl cinnamate),

9 poly (vinyl benzoate),
10 poly (vinyl naphthoate) s

eoeaa «/. mi

11 polyvinyl carbazole,

12 poly (vinylene carbonate) _a

13 polyvinylpyridine,

14 poly (vinyl acetal),

15 poly (vinyl butyral),

16 poly (ethyl methacrylab),

17 poly (butyl methacrylate),

18 poly (styrene / butadiene) ₉

19 poly (styrene / methyl methacrylate) ₉

20 poly (styrene / ethyl acrylate) ₉

21 poly (styrene / acrylonitrile),

22 poly (vinyl chloride / vinyl acetate),

23 P <? Ly (vinylidene chloride / vinyl acetate),

24 poly (4,4'-isopropylidenediphenyl / 4,4'-isopropylidenedicyclohexyl carbonate), . -

25 poly / "4 ₉ 4'-isopropylidenebis (2 _s 6-dibromophenyl) carbonate-7 _s ^;

26 Poly / "" 4.4 ^ -isopropylidenbis (2 _J 6-dichlorophenyl) -carbonat_7 ₅

27 Poly / "4 ₉ 4'-isopropylidenebis (2 _s 6-dimethylpheny1) ■ carbonate? _A

28 'poly (4 ₉ 4 ^l -isopropylidenediphenyl / l _s 4-cyclohexyl-

dimethyl carbonate),

29 poly (4,4 ^f -isopropylidenediphenyl terephthalate / isophthalate), '

30 poly (3 ₉ 3 ^! -Ethylenedioxyphenyltlxiocarbonat) _il

31 poly (4 ₃ 4 ⁱ -isopropyhdendiphenylcarbonat / terephthalat),

32 poly ^^ '- isopropylidenediphenyl carbonate),

33 poly (4,4'-isopropylidenediphenylthiocarbonate),

34 poly (2,2-butane bis-4-phenyl carbonate) ₃ . -

35 poly (4 ₉ 4'-isopropylidene peripheral carbonate / block ethylene oxide) j. *

3.6 Po Iy (4 ₉ 4 <-is opropy lidendiphenylcarbonat-blo ck-

tetramethylene oxide),

37 Poly / ~ 4 _i 4'-isopropylidenebis (2-methylphenyl ') -

carbonate?

9838/1141

38 poly (4j4 ^l -isopropylidenediphenyl / lj ^ -phenylene carbonate),

39 "· poly (4,4 * -isopropylidenediphenyl / lv ^ -phenylen- '

carbonate),

40 poly (4,4 '- isopropylidenediphenyl / 4,4' "- diphenyl-. carbonate),

41 poly (4,4'-isopropylidenediphenyl / 4,4'-oxydiphenyl carbonate),

42 poly (4j4'-isopropylidenediphenyl / 4,4 ^r -carbonyldiphenyl carbonate),

43 poly (4 _J 4'-isopropylidenediphenyl / 4 _> 4'-ethylenediphenyl carbonate),

44 Poly / ~ 4,4 ^f -methylene-bis (2-methylphenyl) carbonate 77

45 poly / ~ l, l- (p-bromophenylethane) bis (4-phenyl) carbonate_7,

46 Poly / ~ 4 _J 4'-isopropylidenediphenyl / sulfonyl-bis- (4-pHenyl) carbonate_ _i 7 _J

47 Poly / ~ l, l-cyclohexanebis (4-phenyl) carbonate_7,

48 poly (4,4'-isopropylidenediphenoxydimethylsilane),

49 poly / 4,4'-isopropylidene-bis (2-chlorophenyl) carbonate j

50 Poly / 'aja, « ¹ _a o ^l -tetramethyl-p-xylylene-bis (4 ^ phenyl carbonate) _7 ,

51 PolyChexafluoroisopropylidenedi - ^ - phenyl carbonate)

52 poly (dichlorotetrafluoroisopropylidene-4-phenyl carbonate),

53 poly (4 _J 4 ^f -isopropylidenediphenyl-4,4 ^l -isopropylidenedibenzoate;

54 poly (4,4 ^l -isopropylidenedibenzyl-4 _J 4 ⁱ -isopropylidenedibenzoate),

55 poly (4.4 ^l -isopropylidene di-l-naphthyl carbonate),

56. Poly / '^^' - isopropylidene-bisCphenoxy- ^ phenyl-

sulfonate ) J7 ₃

57 acetophenone porraaldehyde resins, -

58 poly / "4,4 ^l -isopropylidene-bls (phenoxyethyl) / äthylenterephthalat_7,

59 plienol-formaldehyde resins,

60 polyvinyl acetophenone,

9098 36/1341

19097A2

70 71 72 73 74 75 76 77

chlorinated polypropylene,

chlorinated polyethylene,

Poly (2,6-dimethylphenylene oxide),

Poly (neopentyl-2,6-naphthalenedicarboxylate),

Poly (ethylene terephthalate / isophthalate),

PolydjA-phenylene / ljJ-phenylene succinate),

Poly (4,4'-isopropylidenediphenylphenylphosphonate),

Poly (m-phenyl carboxylate),

Poly (1,4-cy.clohexanedimethylterephthalate / isophthalate),

Poly (tetramethylene succinate), Poly (phenolphthalein carbonate), Poly (4-chloro-1,3-phenylene carbonate), Poly (2-methyl-1,3-phenylene carbonate), Poly (l, l-bi-2-naphthylthiocarbonate), poly (diphenylmethane-bis-4-phenyl carbonate), "Poly / ~ 2,2- (3-methylbutane) bis-4-phenyl carbonate_7,

Poly / "" 2,2- (3,3-diniethylbutane) bis-4-phenyl carbonate_7 ,.

Poly {l, l _T / "" l- (l-naphthyl) _7bis-4-phenylcarbonatJ7 ~

Poly / ~ 2,2-C4-methylpentane) bis-4-phenyl carbonate7, poly / ~ 4,4 ^r - (2-norbornylidene) diphenylcarborate _7,

Poly / ~ 4,4 ^f - (hexahydro-4,7-methanoindan-5-ylidene> diphenyl carbonate_7 »

To be particularly advantageous for the production of photoconductive layers, the use of ¹ polymers and copolymers has been shown to consist of linear polymers with recurring units of the following structural formula:

90983671341

where mean:

Rjj and R, - individually each a hydrogen atom or an optionally substituted alkyl radical or an optionally substituted aryl radical or R ^ and R ₅ together the carbon atoms which are necessary to complete a cyclic hydrocarbon radical;

Rg and R ₁ each represent a hydrogen atom or an alkyl radical having preferably 1 to 5 carbon atoms or a halogen atom, e.g. B. a chlorine, bromine or iodine atom, and - ■

Rq is a divalent residue of one of the following structures? - turformein:

O S O O

Il J Il Il

-oc-σ, -oco-, -co-, -CO-CH ₂ -,

0 CH, 0-.

Il I ³ Il -CO-CH- -CH ₂ -OCO- and

R ₁ J and R ₅ can, for example, have the meaning of methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl radicals or the meaning of, for example, trifluoromethyl radicals or radicals of the phenyl or naphthyl series, it being possible for these aryl radicals to be optionally substituted, e.g. B. by halogen atoms or alkyl radicals having 1 to 5 carbon atoms.

If R ₁ and Rf- together form a cyclic hydrocarbon radical, this radical can, for example, be a cycloalkane radical, e.g. B, a cyclohexyl radical or a polycycloalkane radical, e.g. B. be a norbornyl radical. Preferably ask

909836/1341

Rji, and Rj radicals with up to 19 carbon atoms.

As particularly advantageous diarylalkane polymers for production The photoconductive layers have polymers with recurring units the following structural formula:

where mean:

R. a phenylene radical optionally substituted by one or more halogen atoms or alkyl radicals and .

R ₂ J and Rr radicals of the meaning given.

Such polymers are described, for example, in the United States patents 3,028,365 and 3,317,466.

Polycarbonates with diarylalkane radicals, which can be produced from bisphenol A. Also include polymers which can be obtained by ester exchange between a diphenyl carbonate and 2 _I 2-bis-4-hydroxyphenylpropane, are particularly advantageous polymers for producing the photoconductive layers. Such polymers are, for example, from the following US patents 2,999 75 ° J 3 038 874; 3 38,879; 3,038,880; 3 106 544; · 3 106 545 and 3 106 546 as well as the Australian patent written ζ 19575/56 known. ■ '.- ■' ■ '

Conventional known solvents can be used to produce the photo-capable layers, e.g. B. water, β-- ¹ organic solvents, e.g. B. Aromatic carbon fiber?

(d, h »for the transfer of homogeneous layers of dye polymer into heterogeneous systems)

909836/1 ''. 1

for example benzene and toluene, or ketones, e.g. B. acetone, and ethyl ethyl ketone, or halogenated hydrocarbons, -z. B. methylene chloride and ethylene chloride, ether, e.g. B. tetrahydrofuran, or alkyl or aryl alcohols, e.g. B. methyl ,. Ethyl or benzyl alcohol, as well as mixtures of such solvents.

A wide variety of known organic photoconductors can be used to produce the electrophotographic recording materials be used. This also includes, for example, the known organometallic photoconductive substances, which little or practically no photoconductivity per · ^ show persistence. Typical organometallic compounds of this type are the organic derivatives of metals of groups IVa and Va of the Periodic Table of the Elements, which have at least one aminoaryl radical bonded to the metal atom. Typical examples of such orgahome.tallic Compounds are the iriphenyl-p-dlallylajninophenylderivate of silicon, germanium, tin and lead as well the Trl-p-dialkylaminophenyl derivatives. of arsenic, antimony, of phosphorus and bismuth.

Particularly advantageous organic photoconductor for producing the electrophotographic recording material, the conductors as a photo become known from Amintyρ photoconductor j de <ren common feature is that they _s have at least one amino group. Such organic photoconductors include arylamines such as (1) diarylamines, e.g. B. Diphenylarain; Dinaphthylaihinj N _S N'-diphenylbenzidine;N-phenyl-1-naphthylamine;N-phenyl-2-naphthylamine; N, N'-diphenylp-phenylehdiamine; 2-carboxy-5-chloro- ⁱ l'-methoxydiphenylamine; p-anilinopheilol and N, N'-di-2-naphthyl-p-phenylenediamine and (2) triarylamihe, ζ. B. (a) non-polymeric triarylamines, e.g. B. Trlphenylaminj Ν, Ν, Ν ', N ^f -etraphenyl-m-phenylenediamine; Acetyl,

909836 / 13A1 bad original

triphenylamine; Lauroyl triphenylamine; Hexyl triphenylamine; Dodecyl triphenylamine; Hexaphenylpararosaniline and 4, ² J ^f -Bis (diphenylamino) benzil; 4,4 -BIsCdiphenylamino) benzophenone and (b) polymeric triarylamines, e.g. poly - / "" N, 4 "- (N, N ^I , N'-triphenylbenzidine) _7; polyadipyltriphenylamine; polysebacyltriphenylamine; polydecamethylene triphenylamine; poly -N- (4-viny! Phenyl) -diphenylamine and poly-N- (vinylphenyl) -a, a-dinaphthylamine.

Particularly suitable organic photoconductors are of the amine type Polyarylalkanes of the following structural formula:;

R ¹ CR " ¹

R ""

where mean:

R ", R" ¹ and R "" each represent an aryl radical and

R ^{1 is} a hydrogen atom or an alkyl or

Aryl radicals, with the proviso that at least one of the radicals R ″, R ¹¹¹ and R ″ ″ have an amino radical.

Such compounds can, for example, through amino radicals substituted triphenylmethane leuco bases like them for example from French patent 1 383 46l are known.

Typical photoconductors for carrying out the method of the invention, who deal with the two-phase, hetero? · "Let the genetic system of dye and polymer sensitize, are for example:

909836/1341

TABEL

Connecting

Mr. name of the connection

"4 ¹ , 4" -Bis (diethylamino) -2 · ^ "- dimethyltriphenyl-

methane,

4 ¹ ^ "- Diamino ^ -dimethylaminO ^ ¹ , 2", 5 ', 5 "-. Tetramethyltriphenyl methane, 4', 4" -Bis (diethylamino) -2, ö-dichloro ^ ', 2 "-dimethyltriphenylmethane, ,

4 \ 4 "-bis (diethylamino) -2 ', 2" -dimethyldiphenylnaphthylmethane,

2 ', 2 "-Dimethyl-4,4 ^f , 4" -tris- (dimethylamino) -triphenylmethane,

.6 4 ', 4'! - Bis (diethylamino) -2-dimethylainino-2 ', -

2 ', 5', S '^ tetramethyltriphenylmethane, 4 ^I, 4 "-bis (diethylamino) -2-chloro-2 ^l, 2' -dimethyl-4-dimethylaminotriphenylmethane, 4 ^f, 4" -bis (diethylamino) -4 -dimethylamino-2,2 · ^ "- trimelhyltriphenylmethanj 4 ^t , 4 ^ll -Bis (dimethylamino) -2-chroro-2 ^l , 2 ^ir dimethyltriphenylmethane, 4 ^l , 4" -Bis (dimethylamino) -2 ^l , 2 "- dimethyl-4-

methoxytriphenylmethane,

> 11 4 ^I , ⁱ * "- bis (benzylethylamino) -2 ^f , 2" -dimethyl-

triphenylmethane,

4 ', 4 "-Bis (diethylamino) -2 ^f , 2", 5 ^! , 5 "-tetra-

methyltripheny! methane,:

4 ', 4 "-Bis (diethylamino) -2' ^" - diethoxytriphenylmethane. *

Other known organic hiotoconductors suitable for carrying out the method of the invention. be beispielswei- ^v se described in the following US Patents:

037 861; 3 04l 165; 3,066,023; 3,072,479; 3,047,095;

112 197; 3,133,022; 3,144,633; 3,122,435; 3,127,266;

130 046; 3,131,060; 3,158,475; 3 l6l 505; 3,163,530;

163 531; 3,163,532; 3 I69 060; 3,174,854; 3. I80 729;

180 730; 3,189,447; 3,206,306; 3,240,597; 3,139,338;

909836/1341

3,139,339; 3 1 ^ 0 946; 3 l4l 770; 3,148,982; 3,155,503; 3,257,202; 3,257,203; 3,257 2θ4; 3,265,496; 3,265,497; 3,274,000. ' . '.

The post-sensitization according to the invention or additional The electrophotographic recording materials produced in the manner described are sensitized in advantageously with sensitizing dyes of the type used to make the photoconductive layer will. This means that. For post-sensitization or additional Sensitization in particular to pyrylium dyes, namely pyrylium, selenapyrylium and thiapyrylium dye salts are suitable, solutions of one or more dyes being used for post-sensitization be able to. Although dyes are advantageously used for post-sensitization or additional sensitization as they were also used for the production of the photoconductive layer, this does not mean, however, that for post-sensitization not also other dyes that. known as sensitizing dyes are used can be. However, preference is given to producing the photoconductive layer and also for post-sensitization Sensitizing dyes of the same structure or of the same type are used.

A wide variety of customary known polar hydrocarbons can be used to prepare the solutions for the post-sensitization st off solvents are used. As particularly beneficial has the use of halogenated hydrocarbons proven. It is of course essential that a solvent is used, which is able to dissolve the dye. Furthermore, the solvent should be at least one allow certain swelling of the polymer component of the photoconductive, aggregate-containing layer. The solvent should also be volatile * Preferably it should be

909836/1341

Have a boiling point below 2OO ° C. Particularly suitable Examples of solvents are halogenated, short-chain ones Alkanes having 1 to 3 carbon atoms, e.g. B. dichloromethane, Dichloroethane, dichloropropane, trichloromethane, trichloroethane, Tribromoethane, trichloromonofluoromethane, trichlorotrifluoroethane and the like. As well as halogenated benzenes, e.g. B. Chlorobenzene, bromobenzene and dichlorobenzene.

As already explained, the photoconductive layer of a solution may be once or several times with W of a sensitizing dye to be treated of the recording material. This means that several layers of the sensitizing dye can be applied to the recording material. It has been shown that the sensitivity of the recording material can be further increased with each new coating or each newly applied layer. From a practical point of view, however, it has been found useful not to apply more than about eight coats of coating, because after about eight coats the increase in sensitivity decreases.

The concentration of the dye or dyes in the to-. The solution used to carry the sensitizing dye (s) used can vary widely, with a natural one The limit is set by the solubility of the dyes in the solvents used. As functional it has have been found to be, if possible, with highly concentrated on solutions to work. The dye solution can optionally also have other additives, for example those that facilitate the application of the solution, or additives that the Increase solution viscosity! To increase the solution viscosity For example, conventional polymers can be used, e.g. B. High viscosity carbonates * based on BiBphenol A has been manufactured Bind. The coating

909838/1341 _B ad original

ratio can be very different. As functional it has have been found to use coating ratios greater than about 5 ml per 0.09 m. (1 sq to avoid the appearance of stains or mottling effects. It has been found that the coating ratio on the dye concentration or solution viscosity is practically independent. ·

It has also been shown that the total dye concentration a photoconductive one provided with an overcoat layer Layer is not the only reason for increasing electrophotographic sensitivity. So did has shown, for example, that an electrophotographic recording material produced by the process of the invention, d. H. that is, a recording material containing a sensitizing dye both in the photoconductive layer as well as in at least one coating layer, is about four times more sensitive than a corresponding recording material with the same total dye concentration, its However, dye only in the photoconductive Shift has been accommodated. This shows that the increase in sensitivity that can be achieved according to the invention is primarily the result of which is that the dyes in the phdto-conductive Layer and distributed in one or more coating layers will. . ;

The application or the production of the coating layers can by soaking up the solutions through the photoconductive Layer done without changing the thickness of the photoconductive Layer done after coating or application of the coating layer. Usually have the photoconductive Layers treated by the method of the invention or coated to a thickness of about 5 to about 15 n.

909 8 36/1341

An essential feature of the invention is that the dye used to produce the coating layer in the coating solution has its radiation absorption characteristics. ka changed after being picked up by the underlying photoconductive layer. It has been shown that the radiation absorption maximum of the dye (s) after being absorbed by the photoconductive layer or "imbibition" is shifted significantly with respect to the radiation absorption maximum of the dye (s) in solution. The shift in the absorption maximum due to the uptake ("imbibition") of the post-sensitizing dye on the photoconductive
/ Layer is usually in the order of at least about 10 ΐημ.

According to the invention is thus carried out on a conductive layer carrier a photoconductive layer comprising aggregates is produced, which is then subsequently mixed with a solution one or more times overcoated or coated with a sensitizing dye. The dye solution is thereby converted into the photoconductive one Layer sucked in, whereupon the solvent evaporates or evaporates. The electrophotographic recording obtained Drawing material can then be carried out using customary known electrophotographic processes photoconductive layers are required can be used.

The electrophotographic made by the process of the invention Recording material can thus be used, for example, in the context of xerographic processes. In such a method, the recording materials are first stored in the dark and then, for. B, by means of a Corona discharge, uniformly electrostatically charged. This uniform charge is retained by the photoconductive layer because of the insulating Properties of the layer in the dark, d. H. the minor

909836/1341

Conductivity of the layer in the dark. The electrostatic charges on the photoconductive layer are then selectively dissipated by imagewise exposure of the layer. The imagewise exposure can take place, for example, as is customary in contact copying processes or by projecting an image through a lens and the like. During imagewise exposure, a latent electrostatic image is created in the photoconductive layer. The generation of the electrostatic charge image is made possible by the fact that the electrostatic charge in relation to the intensity of the incident or
irradiated amount of light is derived.

The latent electrostatic image obtained can then be developed or else transferred to another layer support and developed here. Both the loaded and the 'unloaded districts can be made visible. So-called electrostatically responsive particles with optical density are used for development. The electrostatically responsive particles used for development can be used in the form of a dust or powder and can, for example, consist of a pigment
in a resinous carrier, ie a so-called toner. An advantageous method for developing such latent, electrostatic images is the so-called development of a magnetic brush. Such development processes are described, for example, in the following US patents: 2-7.86,439; 2,786,440; 2,786 44l; 2,811,465;
2,874,063; 2,984,163; 3,040,704; 3,117,884 and U.S. Reissue Patent 25,779.

The latent images can also be developed, for example, with liquid developers, that is to say with
Developers in which the particles required for development are raised by means of an electrically insulating liquid
the surface to be developed can be applied.

90983S / 13A1

Such development processes are known, for example, from US Pat. No. 2,907,674 and Australian Pat. No. 212,315. '

In the so-called dry development process, the most common method for creating permanent copies is to use developer particles, one of their components consists of a low-melting resin. In this way" it is possible by heating the recording material after applying the developer particles, to melt them firmly onto the surface of the recording material. To this In this way, the developer particles are permanently bonded to the surface of the photoconductive layer. :

It is also possible to do that on the photoconductive layer generated, electrostatic charge image on a second Layer support, e.g. B. from paper to transfer, whereupon this Layer base after development becomes the final copy. Development processes of this type are known, for example, from U.S. Patents 2,297,691 and 2,551,582 and the journal "RCA Review", Volume 15 (1954), pages 469-484.

The following examples are intended to further illustrate the process of the invention.

Example 1 '"

First, a photoconductive layer comprising aggregates was produced by the method known from Belgian patent specification 705 118. First, a solution was prepared having a solids content of about 10 % of the following solids: about 3 wt .- # 4- (4-dimethylaminophenyl) -2,6-diphenylthiapyrylium perchlorate as. sensitizing dye salt, 39 % 4,4 ^t -diethylamino-2 _f 2t-dimethyltriphenylmethane as photoconductor and 58 % of a polycarbonate resin

⁺ Methylene chloride

09 838/134

by reacting phosgene with a dihydroxydiarylalkane or by ester exchange between diphenyl carbonate and 2,2-bis-4-hydroxyphenylpropane (commercial product "Lexan 105", manufacturer: General Electric Company, USA).

The solution was subjected to effective shear forces. After the solution was sheared, it was applied to a conductive substrate. This conductive substrate consisted of a Pölyäthylenterephthalatfolie, initially with a so-called terpolymer of 2 wt -% had been coated Itäconsäure, 15% methyl acrylate and 83% vinylidene chloride, whereupon a nickel film was deposited on this layer in a high vacuum...

After drying, the photoconductive layer was allowed to dry calmly. After drying it had a layer thickness of about 10 μ.

The resulting electrophotographic recording material was then electrostatically charged under a Gorona discharge source until the surface potential reached a potential of about 600 V as determined by an electrometer probe. The charged recording material was then exposed through a gray scale with density levels by means of a tungsten light source of 3000 ° K. All exposures were made through a short. Wavelength transmitting interference filter with a 30 $ transmission at 600 my. As a result of the exposure, the surface potential of the photoconductive layer was reduced under each step of the gray scale from the original potential V _Q to a lower potential V, the exact value of which depends on the amount of light actually irradiated in heter-candle seconds. .

9 0 9 8 3 6/13 41

SAD ORIGINAL

19Q9742

The results of these measurements obtained were then plotted on a graph in which the surface potential V was plotted against the logarithm of the exposure for each level. _:

The actual positive or negative sensitivity of the photoconductive layer can then be expressed in the form "of the reciprocal of the exposure required ₃ to reduce the surface potential to a fixed, selected value. In the following, if not otherwise indicated, the actual positive or negative sensitivity expressed in the form of the numerical value of 10 divided by the exposure, in meter-candle seconds, which was required to reduce the surface potential charged to δΟΟ V to a value of 50 V. The sensitivities determined in this way were expressed as positive or negative 50 V sag sensitivities (toe speeds).

First, the sensitivity of the with no solution * of a sensitizing dye post-treated recording material determined. After that, the phot ο le it was able to: Layer the recording material by means of an extruder-coating device with a 0.45 solution of 4- (^ - dimethylaminophenyl) -2,6-diphenylthiapyrylium perchlorate coated in dichloromethane. The dye solution was in applied in such a way that on a carrier area of 0.09 m (1 sq.ft.) 2 ml of solution corresponding to 12 mg of dye were omitted, namely in a coating operation.

The sensitivity of the drawing material was then determined again in the manner described. The recording material was then coated a second and a third time with a solution of the sensitizing dye. The results obtained are shown in Table 4 below. -... ^ι . .-.; ..-. "■

6/1341

TABLE 4

Sensitivity - 50V

Optical density . (Sag-sensitive at 600 my )

Comparative experiment

(without coating) 0.98 900

1 coating Ij55

2 coatings 2.0? 1800

3 coatings 2.68 200Ö

From the results obtained it can be seen that each additional application of the sensitizing dye solution results in another Increase "in sensitivity leads.

Similar results were obtained when used as a solvent to produce the coating layers i, l, 2-trichloroethane or mixtures of methylene chloride and. Triehloroethane or bromoform were used.

Furthermore, corresponding results were obtained when a dye was used as the dye in the coating solution which was not identical to the dye present in the photoconductive / layer. For example, corresponding results were obtained when ^ (Jl-dimethylamino- ^; phenyl) -2,6-diphenylthiapyrylium fluoroborate was used as the sensitizing dye in the coating solution.

The recording materials obtained could be in the usual way Develop manner, for example with the aid of liquid developers of the type described in the United States patent 2 907 674 is known.

909836/1341 bathroom

Example 2; - / -

According to the method described in Example 1, an electrophotographic recording material without a coating layer was first produced. This time 10 parts by weight of the photoconductive coating material, which was not subjected to shear stress, were mixed with 90 parts by weight of a corresponding coating material which, however, was not subjected to shear stress, the whole being subjected to a short shear stress. The coating Hiasse was then, as described in Example 1, coated on a tr ^o ägel. ■ '- ■

Thereupon a solution of 0.5 wt .-> «^ - (^ - dimethylaminophenyl) -2,6-diphenylthiapyrylium perchlorate in methylene chloride. rid on the photoconductive layer of the recording material applied. The solution was applied so that on a 0.09 m (1 sq. Ft.) / About 2 ml Solution was omitted. Overall were on 'the photoconductive Layer three of these coatings applied. The recording material obtained was then, as described in Example 1, tested. The values obtained are shown in Table 5 below. · ■ compiled. The absolute value of the optical density is the optical density of the complete element minus one Value of 0.5 for the nickel-coated substrate.

The recording material was then "as described in Example 1," charged and exposed. The sensitivities determined are also compiled in Table 5 below. ■■ '...

Furthermore, a second recording material was produced which, like measurements of the optical density of the photoconductive Layer revealed a corresponding dye concentrate ion like the first described recording material 'exhibited.

909836/1341 bad DRiGiNAL.-

The photoleit capable coating composition, this second for generating the recording material contained 55 wt -.% Of a polymer mixture of 50 wt -.% Of the polycarbonate resin described in Example 1 50 wt -.% Of a highly viscous polycarbonate prepared from bisphenol A having a viscosity of 2 /? 0 centipoise, 40 % 4.4 ^l -dietbyiamine Q-2.2 ^t -.dlmethyltriphenyliiiethan as the photoconductor and 5% 4- (4-dimethylaminophenyl) -2,6-diphenylthiapyrylium perchlorate as the sensitizing dye salt -. * / The coating then became strong subjected to effective shear forces and then for the production of ■ a recording material, as described in Example 1, used.

This second recording material was then dried ate with the formation of an aggregate, photoconductive Layer, · according to which the optical density of the material and the sensitivities as described in Example 1 are determined became. The results obtained are also shown in Table 5 below.

TABLE 5.

Sensitivity -

Absolute optical 50 V (sag density at 600 my sensitivity)

Second record

material -

without coating 1.43 450

First record.

material -

with cover 1.40 l800

Comparison of the results obtained shows that the increase in electrophotographic sensitivity is not just a puncture of the dye concentration, since the second recording material one even slightly

⁺ Methylene chloride was used as solvent

909838 / 13A1

greater paraffin concentration than the first recording material had, however, a sensitivity that was four times lower than the first recording material showed.

Example -3 , - - .-- ■ - ""'

Do the procedure described in Example 1 first a recording material without a coating layer for comparison * purposes. '

A second recording material was then produced in a corresponding manner produced, which differed from the recording material produced for comparison purposes in that that on the photoconductive layer only a dye solvent, namely ethylene chloride, was applied without dye.

Finally, a third recording material was produced in the manner described, but a solution of about 0.4% by weight of 4- (4-dimethylaminophenyl) -2j β-diphenylthiapyryliuin perchlorate in methylene on its photoconductive layer. chloride was applied. The weight ratio of both the second and third recording materials was about 2 ml per 0.09 m ^{2 of support area} (1 sq.ft.).

Using the method described in Example 1, the electrical sensitivities of the recording materials were then determined. The determined positive and negative emp- _; Sensitive elements are compiled in Table 6 below.

90 98-3 8/13 A-I bad original

TABLE 6

Electrical sensitivity

V 50 - ■ - _ 50 (D urc hhang) (slack)

First recording material without coating 900 1000

Second recording material (solvent

630 '900

Third recording material (solvent
and dye coating) 1200-1800

This Example ₅ shows that the solvent used for coating itself does not contribute to an increase in sensitivity of the recording material.

Example 1

The procedure described in Example 1 was repeated using 3IS (4-diethylamino) -l, l, l-triphenylathan instead of 4 _J ^{4'-diethylamino-2,2!} -dimethyltriphenylmethane as a photoconductor. .

From the recording material obtained, first was the electrical sensitivity determined. Thereafter, the recording material in the manner described in Example 1 coated twice with a dye solution, whereupon the electrical sensitivity was re-determined. The results of the measurements obtained are as follows Table 7 compiled.

9098 36/1 3 ^ 1 bath

TABLE 7 Sensitivity - 50V
(Sag sens
possibility). Overall, optical
Density at 600 my 710 '; ■
1400 Reference material
(without cover)
2 coatings 0.76
1.79

Example 5

Following the procedure described in Example 1, another electrophotographic recording material with a photoconductive layer with a thickness of 12.5 my, measured dry, produced without a coating layer. From the received electrophotographic recording material were then determines the total optical density as well as the electrical sensitivity. Then the recording material, as described in Example 1, with a solution of a dye coated, whereupon the density and sensitivity were determined anew. The recording material was then coated twice with a solution of the dye, whereupon optical density and electrical sensitivity were determined again. The results of the measurements are compiled in Table 8 below.

■:> TABLE 8 \

sensitivity

Total optical 50 V (sag density at 600 my sensitivity

Comparative material 1.25 ■ / - "■" * ■ (without cover) 2.00 1100 1 coating 2.95 ; i8oo 2 coatings. 2500

909836/1341 BAD

Example 6 '

Another electrophotographic recording material without a coating layer was prepared according to the procedure described in Example 1, and its total optical density and sensitivity were determined. Thereafter, the recording material was obtained in the photοleitfähige layer, a i _y 25 £ solution of ^ -Cl-DimethylaminophenyD-Sjö-diphenyithiapyryliumfluoroborat in methylene chloride is applied. The dye solution was applied at a ratio of 1.5 ml per 0.09 n (1 sq.ft.). After the coating layer had dried, the total optical density and electrical sensitivity of the recording material were determined. The results obtained are shown in Table 9 below.

TABLE LE 9

Sensitivity -

Total optical 50 V (slack D'ichte at 600 ηιμ receiver photosensitivity i)

Comparative material

(without coating) 0.96 '1000

- 1 coating. · 1.76

Example 7

Following the procedure described in Example 1, a further electrophotographic recording material without Coating layer using ^ - (ii-dimethylaminophenyl) -2,6-diphenylthiapyrylium fluoroborate as a sensitizing dye in the - photoconductive layer. After drying, two were applied to the photoconductive layer Coatings using the dye solution described in Example 1 applied.

90 9836/1 3 4 1

, 38-19QS742

After drying, the recording material was charged as described in Example 1 and exposed imagewise. The resulting latent electrostatic image was then developed by cascade development, as described in US Pat. No. 2,618,552, using a developer mixture of glass beads and toner powder made from polystyrene and carbon black. During the cascade development the electroscopic toner powder remained in the adhere to charged areas of the latent electrostatic image. The developed image was then exceed a Blldempfängsblatt W carry, were melted and then the toner particles by heating the material to the image receiving material. In this way an excellent / quality copy was obtained.

909836/1341

Claims (9)

P A T ENT -A "Ν S F RÜCHE J ^ A method for producing an electrophotographic recording material, in which on an electrically conductive Support a photoconductive layer composed of an organic photoconductor, a dye and a hydrophobic layer Polymer is produced, the photoconductor by a two-phase, heterogeneous system of dye and Polymer, the phases of which are visible at about 2500x magnification, is sensitized, characterized in that, that on the photoconductive layer of the recording material a solution of a sensitizing dye in a volatile hydrocarbon solvent is applied and the solvent is evaporated, the process is optionally repeated one or more times. 2. The method according to claim 1, characterized in that a solution of a pyrylium, thiapyrylium or selenapyrylium dye salt is applied at least once to the photoconductive layer of the recording material. --—- - ^r ~ '~ 3. A process according to claims 1 and 2, characterized in 'that a volatile halogenated Koh'lenwas- as a solvent for coating the sensitizing dye' serstoff used. 4. Process according to Claims 1 to 3, characterized in that a solution of ^ - (^ - dimethylaminophenyl) -2,6-diphenylthiapyrylium perchlorate or -A- \ k -Uimethylaminophenyl) -2, is applied to the photoconductive layer of the recording material at least once 6-diphenylthiapyryliumfluorobo.rat applies. ^: · 9836/13 ^ 1 TS09742 5. Process according to Claims 1 to 4, characterized in that that one is used as a dye to produce the photo-conductive Layer a Pyrylium ^, Thiapyrylium, or Selenapyryiium dye salt used. . /.· ": -6. Process according to claims 1 to 5 »characterized in that the '-' that is used as the polymer for forming the photoconductive layer a film forming polycarbonate resin ^v. '. 7. Process according to Claims 1 to 6, characterized in that % . that to produce the photoconductive layer as Photoconductor used:. ^{:: R} _ _v a) a polyarylalkane of the formula: "-.:."-._" ^: _ '■ .-' β ¹ - c— where mean:. R ¹¹ SR ^"f and R""are each an aryl radical, with the proviso that min- ~ ^r; least one of these radicals is substituted by an 'amino group and. R '■ "■;' a hydrogen atom, an alkyl or Ärylrestj or b) an organometallic compound of a metal of Group IVa or Va of the Periodic Table of the Elements with at least one aminoaryl radical bonded to a metal atom of groups IVa or Va. 8. The method according to claims 1 to 7 »characterized in that that one for the production of the photoconductive layer Solution of a dye salt B and a hydrophobic polymer in the presence of an "organic photoconductor of action 098 36/13 41 19P9742 exposed to strong shear forces, the mixture obtained is applied to the substrate and the liquid evaporates, ^ =. ^; . ^; V 9. The method according to claim 2, characterized in - that one as a volatile, halogenated hydrocarbon, a short-chain, halogenated alkane with 1 to 3 carbon atoms, a * hemogenated benzene or a hemogenated ether with uses up to 5 carbon atoms, IQ. Procedure according to claim 9> characterized in that the halogenated hydrocarbon dichloromethane, dichloro ' ethane, dichloropropane, triohloromethane, trichloroethane, tribroraomethane, Trichloromonofluoromethane or trichlorotrifluoroethane used. Γ