DE1472915B2 - Process for the image-wise dissolution of photoconductive layers - Google Patents

Description

1 2

The invention relates to a method for imagewise conductive layers, in which a charge image

Dissolution of photoconductive layers, in which one produces the photoconductive layer, with one off

Charge image generated on the photoconductive layer, carrier liquid and toner existing, the whole

developed and the developed photoconductive layer photoconductive layer wetting, electrophoto-

developed with a solvent for the photoconductive graphic developer 5 and the developed

Layer is treated. photoconductive layer with a solvent for

It is known (German Patent 1137 625) that the photoconductive layer is treated from and

the development by dusting with a toner is characterized in that the still wet,

made of carbon black and plastic and the toner-developed photoconductive layer with an as

fix the image by briefly heating it. The non-io developers already used the ones with charges

toner covered image portions of the photoconductive (and toner) covered image portions wetting the second

Layer are removed by removing the one liquid that is immiscible with the carrier liquid

Surface of the recording material with a and which is a solvent for the photoconductive

Solvent for the photoconductive layer over layer is or contains, is treated,

wipes. 15 Through this invention it is achieved that one without

The disadvantage of this is that the use of a heat source results in a negative relief image.

Heat source material expense and care in the case of the three methods according to the invention

the application requires. first liquid compared to the charge image

The object of the invention is to provide a method for image an opposite charge, so that the liquid

moderate dissolution of photoconductive layers attracted to the parts of the image covered with charges

admit that developing, fixing and becoming. The second liquid, which is the same as the first

Removing the unexposed parts of the image, the photo-liquid is immiscible, does not settle in the

conductive layer allowed without a heat source covered with the first liquid image parts, so

must be used. that in those parts of the picture the photoconductive

The object of the invention proceeds from a 25 capable layer in which as a liquid is dissolved

Process for image-wise dissolution of photoconductive a solvent for the photoconductive layer

Layers in which a charge image is used on the photo.

conductive layer is generated, developed and the dissolved parts of the image can be through mechanical

wrapped photoconductive layer with a solvent, for example by a water jet or

means for the photoconductive layer, 30 an abrasive, can be removed. In this way

and is characterized in that the charge offset printing forms can be obtained,

picture with one already used as a developer, to the first liquid against removal during

to protect the parts of the image that are covered with charges from wetting the application of the second liquid,

- possibly containing a toner - the first, the two processes with such great speed

Liquid developed and then run with a second 35 that prevented the first liquid from doing so

Liquid that is immiscible with the first and will leave the relevant part of the image. Here

The one solvent for the photoconductive layer is also not destroyed when the charge image

is or contains, is treated. The temperature first liquid is an insulator.

is not critical here. According to one embodiment of the invention, as

By means of the invention it is achieved that the ent- 40 first liquid or, as carrier liquid, is a solution

wrapping, fixing and image-wise dissolving of a liquid silicone in an insulating, liquid one

the photoconductive layer without using a hydrocarbon or an electrically conductive liquid

Heat source can be done. In addition, between speed is used.

the individual process steps no drying. This configuration ensures that the

necessary, so that the procedure in the shortest time ever 45 liquids in the image parts have the tendency

possible time. maintain their limits as they have a high viscosity

Another object of the invention is to have.

a method for image-wise resolution photo- It can also be a toner together with the conductive layers, in which a charge image on liquid is used, which is the liquid the photoconductive layer is generated, developed and absorbed in order to better keep it within its limits, the developed photoconductive layer with a. According to one embodiment of the invention, as Solvent for the photoconductive layer when the second liquid uses a polar liquid, acts is, from and is characterized, becomes this polar liquid after the development that the charge image with a developer as the first liquid, as long as the liquid image used, the charge-covered image parts 55 is still wet, then the polar wetting - optionally a toner separating liquid from the insulating first liquid holding - first developed liquid, with a repelled. The polar liquid is then only second liquid, which cannot be mixed with the first, is able to moisturize the remaining parts of the image, treated and then treated with a solvent for hold.

the photoconductive layer, either with the 60. According to a further embodiment of the invention

first or with the second liquid is miscible, is called polar liquid water, which in a

is treated. Is emulsified hydrocarbon, alcohol or a

The result of this invention is that the alcoholic KOH solution is used.
The drawing explains two possibilities to achieve a positive or a negative relief image 65 Carrying out the method using the Verwill, driving steps.

Another object of the invention is based on FIG. Fig. 1 shows a method with a small number

a method for the image-wise resolution of process steps.

1 472

In step one, a photoconductive layer 2 on a support 3 carries charges 1. The photoconductive Layer consists of selenium deposited in vacuum or of zinc oxide, dispersed in a binder. The substrate is made of aluminum or paper. The charges are on applied in any way, for example by first applying a corona discharge to the photoconductive layer and then subject to exposure through a negative master copy.

In step two, an initial liquid is being used the roller 4 applied. The roller is permeable and carries the first liquid 5 with it. It arises a liquid image on the photoconductive layer 2.

At step three, the second liquid 6 is applied using a roller 7, which is the second liquid contains, applied. The photoconductive layer is through this liquid in those parts of the image, in which the first liquid 5 is not retained, wetted. The two liquids are immiscible, so that the first liquid 5 controls the deposition of the second liquid 6. The liquid 6 contains a agent dissolving the photoconductor.

In step four, a jet of water 8 or some other liquid with sufficient Force is applied, the second liquid and the dissolved photoconductive layer is removed, so that the substrate 3 is exposed. Although the jet can the first liquid 5 and the second Remove liquid 6, but since the first liquid 5 is not a solvent for the photoconductive layer or contains, it is obvious that even if both liquids are removed, the photoconductive Layer is only removed in the parts of the image covered with liquid 6.

In Fig. 2 shows step one charges 10, a photoconductive layer and a support 12. In step two, the roller 13 applies a first insulating liquid 14 to the charges 10. At step three a second polar liquid 16 is applied by means of the roller 15. In step four, a Roller 17, a liquid 18, which is a solvent for the photoconductive layer or contains, is applied. The liquid 18 mixes with the liquid 16, but not with the liquid 14, whereby the photoconductive layer 11 is dissolved in the image parts covered with liquid 16. At step five the liquids 18 and 16 and the photoconductive layer are removed by means of the jet 19, while the photoconductive layer is retained in the parts of the image covered with liquid 14.

It will be appreciated that the liquid 18 can also be selected to be with the Liquid 14 mixed so that just the opposite parts of the image as in FIG. 2 can be removed.

B e i s ρ i e 1 1

A sheet of paper is coated with a coating liquid the end

100 g zinc oxide,
30 g of little modified alkyd resin,

0.1 g rose bengal,

0.01 g fluorescein sodium,

0.01 g brilliant green,

0.02 g cobalt naphthenate,
50 g of toluene

applied.

60 After 6 to 5 hours of drying at 60 ° C., the photoconductive layer is charged at a field strength of 25.4 kV / cm, whereby a surface charge of 300 V is generated.

Then a photoconductive layer is imagewise exposed and off in a developer

90 parts by volume of a liquid hydrocarbon and

10 parts by volume of a liquid silicone with a viscosity of 200 cPs

developed.

Development is done either face down in a metal bowl for 30 seconds up to 1 minute or by rolling a metal roller four times. The liquid silicone sets on the loaded parts of the image. Then the wet sheet is mixed with a liquid hydrocarbon rinsed to remove the excess and while still wet in an emulsion of the following composition placed:

60 ml of liquid hydrocarbon,

40 ml water,

1 ml Oktylphenyläthylenoxydkondensat (cloud point 45 to 50 ⁰ C, a non-dissociated wetting agent).

This emulsion covers the parts of the image not covered with silicone with water.

The still moist sheet is then immersed for 20 seconds in a 10% solution of potassium hydroxide in ethyl alcohol, so that the photoconductive layer is dissolved in the parts of the image covered with water. Then the leaf is washed off in a water bath or under a jet of water. The planographic printing plate obtained is wetted with a 5% ig ^en sodium orthophosphate solution in water and provided with greasy ink.

B e i s ρ i e 1 2

The procedure is as in Example 1, but instead of the silicone-containing developer, a developer is used used, which is manufactured as follows:

100 g Monolite Red (Color Index No. 12075),
200 g lithographic varnish (linseed oil, tung oil, soybean oil or terilla oil thickened by heating),

100 g pentaerythritol resin, melting point 121 to 132 ° C, acid value No. 20 to 30, density 1.05 to 1.15 p / cm ³ ,
20 g cyclohexane

are mixed together in a billet mill. 1 g concentrate is dispersed in 100 g of a liquid hydrocarbon with a flash point of 57 ^{° C.}

EXAMPLE 3

The procedure is as in Example 1 or 2, but an aluminum sheet is used as the layer support. The exposed aluminum sheet is etched with 10% hydrofluoric acid. After removing the remaining photoconductive layer from the etched aluminum sheet, a gravure form is obtained.

Example 4

The procedure is as in Example 1 or 2, but a layer support made of glass and a photoconductor are used

5 6

from zinc oxide, bismuth trioxide, lead iodide, cadmium are. Used after heating leaf for 1 minute on sulfide or cadmium selenide. The image is 65 ⁰ C, the softened parts of the image by excessively exposed glass is etched with hydrofluoric acid. wash with xylene, cumene or turpentine oil substitute. Ornamental glass is obtained. . removed.

Ee i s ρ i e 1 5 Example 11

The procedure is as in Example 1 or 2, but the procedure is as in Example 6 (amorphous

a brass sheet is used as a layer support. Selenium as a photoconductor), but the solution of

The image-wise exposed brass leaf is replaced by potassium hydroxide in ethyl alcohol

Gold, chrome, silver or nickel electroplated. io carbon disulfide or by a solution of

You get a very wear-resistant plate for printed potassium sulfide or sodium sulfide in a higher

Circuits that have a hard edition. Alcohol.

Example example 12

The procedure is as in Example 1 or 2, but the procedure is as in Example 7, but a plastic sheet is replaced as the layer support and aromatic solvents are replaced as the potassium hydroxide solution by benzene or another photoconductive layer in a vacuum chamber.
Amorphous deposited 0.5 to 5 microns thick. .
Selenium, sulfur or arsenic trichloride are used. Example 13
Instead of 20, the silicone-containing developer contains the recording monolite red (Color Index No. 12075) specified in Example 1, microlite material, which is charged, exposed and developed, black CT (R ä m ρ p, Chemie-Lexikon, 5th edition , The developer is made by wedding
Vol. 2, column 3233) and instead of the liquid carbon ■,.
Hydrogen with a flash point of 57 ° C terpene ] ° _n § water-soluble starch and
tin oil substitute with 45% aromatic hydrocarbons - ₂₅ ⁵⁰ S ^a f hydrocarbon with a flame substance. Instead of an »octyl point, the emulsion contains ^{57 ° C}

phenyläthylenoxydkondensates «an anionic cleaning agent to a paste and dispersing of Ig paste in

agent from the group of olefin sulfates, and the 100 g of the hydrocarbon with a flash point

Ethyl alcoholic potassium hydroxide solution is prepared from 57 ° C. The strength is in the

a 10 ° / ₀ by weight solution of NaOH in water or methyl 30 loaded and the hydrocarbon in the non-

alcohol replaced. A letterpress form is obtained. - loaded parts of the image. The recording

material is then immersed in water, which the

■ Example / strength dissolves. Here, the hydrocarbons remain

A wooden support is dipped into fabric-covered parts of the image from the washing process

covered with an organic photoconductor. This 35 untouched.

Recording material is charged, exposed and the recording material is treated with 30% strength with a developer according to Example 2, which instead of acetic acid, which mixes with the water and which dissolves from Monolite Red (Color Index No. 12075), Peerless zinc oxide. The recording carbon black (Color Index No. 77266) contains developed. material is colored (pictorially).
Proceed as in Example 1, but 40

the emulsion consists of a petroleum distillate, B eis ρ ie 1 14
Water and triethanolamine oleate. To the pictorial

Resolution of the photoconductive layer is 10 seconds procedure is as in Example 13, but using a solution of 5 ° / ₀ sodium hydroxide is applied, the strength announce long by resin acacia, tragacanth or Äthylin water. A planographic printing cellulose 45 is obtained.

shape. . .

Example 15

Example8 "., ... ■. ■ .." ". ,. ,,

The procedure is as in Example 13, however

The procedure is as in Examples 1, 2 or 6, a recording material with a selenium layer

however, one is used to produce a printed 50 as in the example and the strength is through

Circuit of suitable multilayer substrate replaces potassium sulfide. When moistened with water

used. The copper layer contained in it can attack the potassium sulfide and make it possible

by etching with ferric chloride or an acid form- its removal,

be removed moderately. The remaining copper _. .

lines are characterized by their absence of gaps and 55 Example 16

Edge sharpness off. The procedure is as in Example 13, however

. . in a recording material with poly- (n-propenylcarb-

U e 1 s ρ 1 e 1 y _azole ) used _as ph _oto i _e j _ter and the strength through

The procedure is as in Examples 1, 2, 6 or 7, palmitic acid, lauric acid or myristic acid as well

however, a fabric made of tree 60 the hydrocarbon with a flash point of

wool, wool or synthetic fibers are used. 57 ° C by a hydrocarbon with a boiling point

The fabric can be colored imagewise. point of 150 ° C, with silicone oil or with paraffin

. oil replaced.
Example 10

The procedure is as in example 2, but at 65 B e 1 s ρ 1 e 1 17

Place the potassium hydroxide solution in ethyl alcohol The procedure is as in one of Examples 1 to 16,

a solution of crude oleic acid in xylene is used, however the photoconductive layer is replaced by the

which softens the parts of the image, the water-moistened solution of 1 to 10 ^u / ₀ acetone in water or through

a solution of ethyl chloride dissolved in an alcohol.

Claims (6)

Patent claims: 1. Process for the image-wise dissolution of photoconductive layers, in which a charge image generated on the photoconductive layer, developed and the developed photoconductive layer with a solvent for the photoconductive layer is treated, thereby marked-io net that the charge image with one as a developer already used, wetting the parts of the image covered with charges, if necessary a first liquid containing toner and then developed with a second liquid, which is immiscible with the first and which is a solvent for the photoconductive layer or contains, is treated. 2. Process for the image-wise dissolution of photoconductive layers, in which a charge image generated on the photoconductive layer, developed, and the developed photoconductive layer is treated with a solvent for the photoconductive layer, characterized in that that the charge image was already used as a developer with one covered with charges Image parts wetting, optionally containing a toner, first liquid developed with treated with a second liquid, which is immiscible with the first, and then with a solvent for the photoconductive layer, either with the first or with the second Liquid is miscible, is treated. 3. Process for the image-wise dissolution of photoconductive layers, in which a charge image generated on the photoconductive layer, with a consisting of carrier liquid and toner, the developed and the entire photoconductive layer wetting, electrophotographic developer developed photoconductive layer is treated, characterized in that the still wet, developed photoconductive layer with one already used as a developer, the one with charges (and toner) covered parts of the image wetting the second liquid with the carrier liquid is immiscible and which is or contains a solvent for the photoconductive layer will. 4. The method according to any one of claims 1 to 3, characterized in that the first liquid or as a carrier liquid a solution of a liquid silicone in an insulating, liquid one Hydrocarbon or an electrically conductive liquid is used. 5. The method according to any one of claims 1 to 3, characterized in that the second liquid a polar liquid is used. 6. The method according to claim 5, characterized in that the polar liquid is water, that is emulsified in a hydrocarbon, alcohol or an alcoholic KOH solution is used. 1 sheet of drawings 009 542/320