SU966656A1 - Electrochromatographic material - Google Patents

Description

 . - .. The invention relates to electrophotography can be used in copying machines for obtaining enlarged copies from microfilms in direct copying mode to the facing without changing the developing composition. Electrophotographic material containing selenium with an admixture of an mouse is shifted to which the photosensitivity region is shifted to red. spectrum band t. However, in the blue-green region of the spectrum, its photosensitivity is small. This leads to the fact that its effective photosensitivity does not exceed that of selenium, and therefore does not allow an increase in the speed of copying devices. The low sensitivity of selenium mixed with a mouse in the blue-green region of the spectrum is due to the fact that the material has a high concentration of deep levels of electron capture in the near-surface layer. As a consequence, most of the electrons generated by highly absorbing blue-green light either recombine with photogenerated holes or are captured to deep levels outside the photogeneration region and form a near-surface negative charge that prevents electrons from drifting to the substrate. In addition, an electrophotographic material with an admixture of a mouse has a short time of dark potential drop, which excludes its use in some types of commercially available electrophotoapparatus. In the apparatus for making copies from microfilms, where incandescent lamps having sufficient radiation power are used in the entire visible spectral region as a projection light source, to increase the copying speed, it is necessary to give the material sensitivity in both the blue-green and red regions of the spectrum, those. to expand the range of its sensitivity to the entire visible zone of the spectrum. The purpose of the invention is to improve the region of the spectral sensitivity of electrophotographic material with a negative charge and increase its effective C1 sensitivity. 39 The goal is achieved by the fact that in electrophotographic material based on selenium, indigo carmine in the amount of 0,, 6 wt.% Is used as a dopant. Shadigokarnia molecules, localized at the points of rupture of linear and ring selenium chains, promote crosslinking of polymer molecules of selenium and a decrease in bulk and surface defects, which leads to a decrease in activation energy for photogeneration of charge carriers in amorphous selenium and a decrease in the concentration of recombination centers and adhesion ronov and holes. As a result, in the village-i layer with the introduction of indigo-carmine admixture with a negative charge, the photosensitivity increases in the region of 400-600 nm. In addition, the indigo carmine impurity increases the rate of formation of the microcrystalline phase of hexagonal selenium at the selenium – substrate interface, which also leads to an increase in the photosensitivity in the red region of the spectrum (600–750 nm). At indigo carmine concentrations in selenium exceeding 0.6%, the time of dark potential drop in electrophoto is reduced, which makes it difficult to use it in some types of electronic camera devices. in the red parts of the spectrum it becomes insignificant, the effective photosensitivity of the electrophotographic material approaches that of a known material containing selenium without impurities. The proposed material is made as follows. otipa30M. Source selenium 1 of the UHF-2 GOST 6738-71 and indigo carmine grade h.d.a. TU-6-09-714-71 in the amount of 0.25 wt.% With respect to selenium is placed in a quartz ampoule. The ampoule is evacuated to a residual gas pressure of 10 torr and placed in. the furnace, which is heated at a rate of 80 C / h to 320 C. At this temperature, the alloy is kept for 4-5 hours with continuous stirring, carried out by oscillating slopes of the furnace, then cooled to room temperature for 1.5 hours and crushed. Then the alloy is placed in a tantalum boat and a layer of 50-70 µm thick is applied to the electrically conductive layer by the method of thermal evaporation from the melt in vacuum. substrate heated to 30-80 ° The cusp of the primer is carried out in a vacuum of 1 10 1 10 Torr, condensation on the substrate is carried out at a speed of 4-25 µm / min. The spectral photosensitivity of the proposed material for three different indigo carmine concentrations is given in the table.

Concentrated Indigo Carmine material q,% Known (.) 8-10 8-10 1-10

0.15-10® 3-10 1.5-10 5-10

Proposed

7-10 4-10 3.5-10 1-10 7-10

0.25

9-10 5.5-10

0.6

Its effective photosensitivity at negative charging according to the criterion of the potential half-decay is 0.6 (lx) (color temperature of the light source is 2850 ° K), the initial potential at negative charging is 1100-1800 V (with a layer thickness of 50-70 μm), time dark potential drop to 50% of the initial 1.5-2 minutes.

1-10

2-10 1-10

1-10

6-10

4-10

MO 6-10 4-10

6th

As can be seen from the above data, when negatively charged, the layers have a sufficiently high photosensitivity in a wide spectral range, while the initial potential and the time of the dark potential drop have values close to the corresponding parameters of commercial selenium photoelectric layers, which allows the use of 400. G 500 T 550 j 600 G 650 1 700800 Spectral photosensitivity, Sj, at, nm 2-10 2-10 4-103,5-lO

59666566

these layers in a serial electrophotograph, so that, for the purpose of rasratura, for example in apparatus of the type ER-M, to broaden the region of the spectral sensitivity, get positive copies with a negative material

and positive microfilms at one and only increase its effective sensitivity of the same developer., as an alloying additive is used .. 0.6 wt.%.

For rum la invented and sources of information

Electrophotographic material containing- 10 1.i Electrophotography and magnetography. Sb., Stichiy selenium with a dopant, about t and u-Vilnius, Mintys, 1972, p. 215-222.

 IndigarMin is used in an amount of 0.1, taken into account during the examination

Claims (1)

Claim Electrophotographic material containing 10 selenium with a dopant, o Fused in that, in order to expand the spectral sensitivity of the material during negative charging and increase its effective sensitivity, indigo carmine in the amount of O, ΙΟ, 6 weight is used as a dopant. %