DE2308070C3 - Method for producing an electrophotographic recording material - Google Patents

Description

On the other hand, is used to relieve tension during the

Avoid cooling, at low temperatures

30 ren vapor-deposited, the wetting of the support by the photoconductive layer turns out to be so

The invention relates to a method for the production of poor quality that also soon detachment of the pholes of an electrophotographic recording layer from the substrate,
terials in which selenium, a selenium alloy or an object of the invention is the adhesion of a

Selenium compound as a photoconductor in a vacuum under 35 photoconductor layer on a support with under formation a photoconductive layer is vapor-deposited onto a different expansion coefficient of photoelectrically conductive substrate. to improve conductor layer and substrate.

Electrophotographic Process and Apparatus This problem is addressed in a process for

The production of an electrophotographic recording sheet has been developed for this purpose in the field of duplication technology Spread found. They are based on the nung material, selenium, a selenium alloy Property of the photoconductive material, in the case of Beiich or a selenium compound as a photoconductor in the Vatung with an activating radiation the elec- tric to form a photoconductive layer see resistance change. applied to an electrically conductive substrate

After electrical charging and exposure with vaporization, according to the invention, an activating radiation can produce a latent electrical charge at a temperature above the glass transition image, which corresponds to the optical image ^{, on a photoconductive layer at most 10 11 O of the photoconductive layer} is equivalent to. On
This is because such an increase in the conductivity of the photoconductive layer takes place in the exposed areas

instead of the electrical charge being evaporated over the conductive 50 ters.
Carrier - at least partially, but in any case more strongly Fs it is advisable that the initially deposited

temperature of the photoconductor and at least 90% photoconductive layer at a temperature below the glass transition temperature of the photoconductive

than in the unexposed areas - can flow off, while the electrical charge is essentially retained in the unexposed areas; she can go with a powder, a so-called toner, made visible 55 and the resulting toner image, if necessary should finally be transferred to paper or other support.

As electrophotographically active substances

dene layer has a thickness of about 1 μίτι. For arsenic selenium alloy whose composition corresponds as As ₂ Se _3, it is recommended that the ersie partial layer at a temperature above 18O ⁰ C, preferably at about 200 ° C to apply. The remaining portion of layer, for example about 10 μηι is mainly at a temperature below about 100 ⁰ C, preferably from about

both organic and inorganic substances 60 60 ° C, deposited.

used. Among them have selenium, selemlegienin- photoconductive layers made after the process

genes and compounds with selenium are of particular importance.

To make images with good contrast and high

deposited according to the invention on a layer support will adhere very well and also for the long term. Because of the high rate of

Achieving sharpness is known to depend on the temperature of the first layer applied, along with the other 65 Conditions required that the charge, which is based on good wetting, are on the other hand at the same time

the photoconductive layers is applied, after exposure to the exposed. Make quick,

tig but not endangered by tensions that arise during cooling. Because at high

At a higher temperature only a very thin layer is deposited and only this very thin layer on top Layer is cooled, the adhesion is not adversely affected

Another advantage of the method according to the invention compared to a process in which vapor deposition only takes place at high substrate temperatures is given by the better yield of the vaporized material. Since the vast majority the layer is evaporated at low temperatures, there is also no significant re-evaporation from the substrate surface.

Claims (3)

Patent claims: can flow off evenly and undisturbed. For this there is an intimate and even touch between the conductive support and the photoconductive layer are necessary. The disadvantage of the known designs of an electrophotographic recording material is that that the demand for intimate and even contact can only be fulfilled with difficulty, since it can in the case of the substrate and the photoconductor about substances . ' 1. A method for producing an electrophotographic recording material, wherein
Selenium, a selenium alloy or a selenium compound as a photoconductor in a vacuum with formation
a photoconductive layer is vapor-deposited onto an electrically conductive layer support, -; ..,., u · u * characterized in that high- »with quite different thennisdien extens 10 · / # of the photoconductive layer is a voltage coefficient. This is especially true for Temperature above the glass transition ternary selenium alloys with a proportion of temperature of the photoconductor and at least 90% or more than 20% by weight arsenic, such as the photoconductive layer at a temperature As., Se "that for example on a glass substrate with below the glass transition temperature of the 15 a conductive intermediate layer of tin dioxide on-photoconductor be vaporized. is brought. Such layers have only a 2. The method according to claim 1, characterized by low adhesive strength, which makes its application strong indicates that this is impaired at a temperature above. the glass transition temperature of the photoconductor. If at high substrate temperatures, especially a 1 tun thick photoconductive layer is produced 20 at temperatures above the glass transition. temperature is evaporated, is initially the 3. Process according to claim 1, characterized in that the layer support is wetted by the photoconductive, ide indicates that 10 "h of a selenium alloy of the layer is good. When cooling to room temperature formula As ₀ Se ₃ at a temperature above, however, the photoconductive layer becomes detached 180 ⁰ C., preferably at 200 ° C, and 90 · '· s at 25 ^c of the substrate due to stress cracks at a temperature below 100 C, preference on whose cause expansion coefficient in its various passes at 60 ° C, are evaporated. to is looking for.