DE1948078B2 - METHOD OF MANUFACTURING A LITHOGRAPHIC FLAT PRINT FORM AND LITHOGRAPHIC PRINTING PLATE - Google Patents

Description

19484) 78

tidruckfto solved the thereby marked that Daanemangsubsütwertesa-NaphÄoUindem direct attachment to the bydjoxys ^ sttaiierten Risg hsutuenten sit as alkyl, aryl, alkojty,

/ Ioxy-, hydroxy- and / or ammogropene exist, adgemaßas reaction groove barrel emelithographic printing plate with a hydrophilic printing layer which fan ionic iodide ak reactants contains, applies and for the formation of a pressure bath at least -'- heats the image-related areas.

Such normally reactive oc-naph- -thols, such as 4-methoxy-1-naphthol, are in the "; USA.-Pa $ Address 3,094,619 and will be

by exposure to ultraviolet rays or by exposure in the presence of a sensitizer, such as Erythrosine, desensitized and with visible light are therefore particularly suitable for reproducing pinched or other graphic templates

The lithographic planographic printing press made by the method of the invention enables manufacture many thousands of prints with excellent image quality

According to one embodiment of the method of the invention one transfers the -naphthol from a uniformly coated transfer sheet from image-wise. The imagewise transfer of the Λ-naphthol from the uniformly coated transfer sheet can be done by imagewise heating the transfer sheet.

The transfer sheet can be in the imagewise areas by applying a different radiation absorbent Original and intense Bestrah-Jung of the original are warmed.

According to another embodiment of the method of the invention, a transfer sheet is used, with the * -naphthol only in the areas shown in the picture is present and heated uniformly to transfer the α-naphthol.

A transfer sheet in which the Λ-naphthol only can be present in the imagewise areas by reflex exposure of a graphic original be formed by means of actinic radiation, the transfer sheet initially being a unitary one Coating of a «-naphthol and light reducible dye, so that the Λ-naphthol in combination with the dye is image-appropriately desensitized by the actinic radiation will.

Thus, the combination of light reducible dye with the 4-methoxy-l-naphthol or a correspondingly substituted x-naphthol described in U.S. Patent 3,094,417 a transfer sheet that readily image-wise desensitizes upon reflex exposure to visible light can be. The direct heating of the thus exposed transfer sheet in direct contact with the lithographic printing plate with the hydrophilic printing layer containing the ionic iodide leads to form a faint blue image on the lithographic printing plate, which is predominantly oleophü and is ink receptive and surprisingly resistant to peeling or removal. Lithographic Printing plates that have been provided with an image in the manner described many thousands of prints with no noticeable degradation in image quality or opacity.

The invention is also based on the object of providing a method which is suitable for carrying out the method of the invention to provide lithographic printing plate. - *> - *?

This object is achieved according to the invention by a Hthographic printing plate released, which is thereby marked is that it is a hydrophilic Drackschiclit has, on the surface of which an ionic iodide is present as a reactant

An inorganic iodide, such as sodium or potassium iodide, can be used as the ionic iodide.

"According to the emervorteOTiaften execution form of the Uthographic Printing plate, however, the ionic iodide is an organic compound.

As was further found, it is advantageous if this consists of an organic compound

j§ iodide is eia quaterocres ammonium iodide. The quaternary Ajnkonium iodide and as found is, to a particularly high degree, a disapproval in the hydrophilic printing layer resistant to storage at high moisture content.

ao To typical organic compounds with ionic be Iodides, which have great resistance to contamination, include methyltriethylaramonium iodide, Propyltributylammonium iodide, Ethyltriäthanotammoniumjodtd, Ptenyltrimethyl-

ss ammoniuuyodid, methyltri- (2-nitriloethanol) -ammo-

nium iodide, l-ethylchinaldinium iodide, 1-methylquino-

linium iodide, 1-ethyl pyridium iodide, trimethylsulfonium iodide and trimethylsulfoxonium iodide.

Nonionic iodides or iodide compounds in the hydrophilic printing layer, such as. B. iodoform, carbon tetraiodide, Phenyl iodide and butyl iodide are ineffective as reaction partners for the Λ-naphthols, as can be determined using the simple test procedure described below.

First, a stock solution of 4-methoxy-1-naphthol made in equal parts acetone and water. For this purpose is the pure connection ineffective; a material, however, that is exposed to light exposure or contact with air is fully effective. Accordingly, if not exceptional precautions have been taken are to ensure an application of pure compound, a solution under normal Laboratory conditions and procedures have been established suitable to all requirements of the test. A small amount then becomes a small proportion of the solution thus prepared added to a solution from the compound under test. The rapid formation of a deep blue discoloration shows that the compound is suitable as a reactant. The reactant concentrations and quantities are chosen so that the color change can be recognized. The non-ionic compounds do not cause the mentioned color formation, while the blue color with ionic iodides is obtained quickly will.

Usable lithographic printing plates include silica treated aluminum plates or other hydrophilic metal plates. the

6p lithographic printing plates preferably have a size-stable support on which the hydrophilic pressure layer is located.

The ionic iodide is preferably in the hydrophilic printing layer in an amount of about 0.025

up to 2.5 g / m ⁴ available. An amount of 0.025 g / m * of the iodide is suitable if this is carefully applied as a surface coating, although this is usually the case with operational coating

5 6

larger amounts are required, such as. B. 0.4 g / m ^s , is kept heated. When removing the

to get a full. To guarantee plating, wear sheet is found that the plate is a

On the other hand, there are still good results with 2.5 g / m ^{2 of a} faint blue image corresponding to the printed one

Iodide has been obtained if it has the original hydrophilic image

The print has been incorporated. Much larger 5 The plate is etched with an acidic aqueous solution

Quantities of these iodides tend to fix the wetted parts, placed on a press uad for printing

To diminish the oleophilic image and therefore used the life of several thousand excellent prints to shorten the duration of the pressure plate.

The ionic iodide must be at or near the above Example 2

surface of the hydrophilic coating must be present in order to io

an immediate and effective implementation with the following recipe, a coating is

transferred reactants to ensure. Therefore preparation mass:

can teae the material into the crowd before ^{teasing it}

but it becomes more effective in the form of polyvinyl alcohol 5

a subsequent top coat is used, which is based on 15 kaolin 50

the previously drawn up, dried and insoluble glycerin 0.5

made hydrophilic material is applied. One-dimethylolurea 1

multiple dabbing of the plate surface with a potassium iodide 1.5

dilute aqueous solution of the reaction partner under butanol (antifoam agent) 4

Using a saturated pad of water is about 150% full of water

effective, although generally uneven to 200 moderate or incomplete coatings are achieved thereby.

The use of an applicator roller, a print run- The amount of water is just enough to make one

Squeegees or other mechanical devices allow a smooth peelable mixture to be obtained. The crowd

more precise application. The reactant can after 45 is on a dense paper backing for a lithograph "

an alternative method of working the hydrophilic over-phical printing film of great wet strength with a

tensile mass before applying the latter to the coating weight after drying of 11.8 g / m *

Underlay can be added. applied as a layer. The coating weight is not

The lithographic printing plate according to the invention is critical, but should be sufficient to produce a complete can, according to a further embodiment, of a covering and a smooth surface, a paper base and a coating of a hydrophilic while at the same time excessive curving of the hydrophilic, water-soluble binder and a hydro sheet or cracking in the coating avoided philic finely divided filler, which should also be. The leaf is dried and the overwater soluble ionic iodide contains. The hydro- traction by heating for one hour to 6O ⁰ C insoluble phile layer can z. B. clay or some other powder-35 made so as to obtain a lithographic printing plate shaped mineral filler in a cross-linked or on.

Another way of insolubilized polyvinyl alcohol. A transfer sheet is made by coating a

or another water-insoluble, hydrophilic, thin, non-porous, slightly calendered and

Contain binders. Plasticizer, hygroscopic table-transparent paper backing with a mass,

Agents, coloring substances and other auxiliary substances or 40 die

Modifying agents can, if desired, benefit

be at hand. 4-methoxy-1-naphthol 10

In the illustrative examples below are cellulose acetate butyrate 3

all parts by weight, unless otherwise indicated - diphenyl phthalate 0.3

give is. 45

B bis ο ie 1 1 ⁱⁿ g ^enu 8 ^enii contains acetone to make a liftable

^p solution, and subsequent drying hot -

A commercially available photosensitive overlay. The dry coating weight is approx

support sheet, as in U.S. Patent 4.5 g / m ² .

3 094 417 is described, and the erythrosine and 50 The transfer sheet is in direct contact 4-methoxy-l-naphthol in a polymeric binding (face to face) with the lithographic medium on a thin, transparent surface, a printing plate, and a document with content, is placed against a printed original, the printed image areas on a thin airmail then Evenly through the transfer layer of paper is exposed with the back to the transfer of a tungsten filament lamp. The 55 sheet laid. Layer exposure consisting of three sheets is just enough for a complete structure with the heat-sensitive layer on the Desensitization in the areas that are the reflective back side of the original is then rendered by an infrared unprinted areas of the base copier out. A blue picture is on the stir, out. lithographic printing plate. The plate

The transfer sheet is then etched in a direct 60 and set on the press, making contact (face to face) to a lithographic large number of lithographic prints, graphic printing plate, which is a hydro- The same transfer sheet is image-forming phile printing layer on a dense paper backing on one or more further printing plates according to. The printing layer is suitably dabbed with a dilute solution of the same procedure, an aqueous potassium iodide solution and then applied. . been dried. The lithographic printing plate with ö e s 1 ρ 1 d 1 3 the transfer sheet is then a few seconds A lithographic printing plate is relevant to a smooth hot plate at 12O ⁰ C ge layers of a paper base for a lithographic

Printing plate or film with a mass that is etched and used on the press, with a

large number of prints is obtained.

^e The printing plates made according to this example

Polyvinyl alcohol ..... 5 remain in a humidity chamber after storage

Sound ................. ...... 50 5 fully effective.

Glycerin; ..............; ......... 0.5 Example 4

Glyoxal ......... 1 printing ink is in a volatile liquid

Butanol 3 alcohol-ketone mixture dispersed, so that one for

Water sufficient for brushing on and ink suitable for writing. Certain

Fractions of this ink are made up of small amounts. The coated sheet is dried and, as in tration, is in the range from 0.5 to 4%. Heated under Example 2. The dry cover using a felt-tip pen with the weight is 11.8 g / m *. 15 different inks characters on a lithographic. The applied layer is then made further with a printing plate which has been prepared as described in Example 3, aqueous 3% solution of tetraethylammonium. The plate is then iodide coated with a coating weight after drying for a few seconds against a heating plate of 0.4 g / m *. hold, which has been heated ^{to 8O 0 C.} The plate A transfer sheet, which is etched as in Example 2 ao, and used on a press. Each which has been produced is used to produce distinctive characters made with ink that did not contain naphthol in a radiation-absorbent image and background, is not shown,
areas on the uncoated surface with ge The individual tested naphthols are:
Suitable characters made with a typewriter and

applied by hand lettering, ver as 4-methoxy-l-naphthol,

see. The transfer sheet is against the litho- 2-methyl-4-methoxy-l-naphthol,

graphic printing plate placed, and the layer structure 4-ethoxy-l-naphthol,

is as in Example 2 by the infrared copier 1,4-dihydroxynaphthalene,

device, with blue image areas on the 1,3-dihydroxynaphthalene,

Plate surface are formed. The printing plate 30 is 4-amino-1-naphthol.

Claims (12)

ί 948 078 ι 2 Iodine concentration in the surface area of the
Claims: called cover is present. X. Process for the manufacture of a lithograph! - s > schea flat printing form, characterized in that that one is a ring-substituted «-Naphthol, in which in direct binding to the hy- The invention relates to a process for the preparation Hydroxysubstituierien Ring etch substituents, those of a lithographic planographic printing form as well as one from alkyl, aryl, alkoxy, aryloxy, hydroxy ίο lithographic printing plate for carrying out a and / or amino groups exist, figuratively as such a process, Reactant to a lithographic print- D $ s duplicating graphic material using plate with a hydrophilic printing layer, which is a help of lithography is known that contains ionic iodide as a reactant, on a predominantly hydrophilic surface brings and for the formation of a print image we- 15 oleophilic dye-absorbing BQdbereich that the at least the image-related areas heated, image areas correspond to the original, can arise. 2. The method according to claim I ₁ . Oil paint is recorded selectively from the image areas by ingesting the naphthol, while the non-image areas are appropriately transferred in a state that is wetted by a uniformly coated transfer sheet of image water and is ink-repellent. stay like that. The color is then, either directly or 3. The method according to claim 2, characterized by means of a transfer sheet on the surface draws that the transfer sheet overzur image-wise a paper or other printing sheet Heat transfer of the naphthol. wear. 4. The method according to claims 2 or 3, there are numerous processes for forming the color through characterized in that the transfer-receiving image has been developed. So can sheet in the image-related areas by applying a wax image on a water-absorbing surface different radiation-absorbing surface, z. B. with wax crayons or by a Original and intense irradiation of the original by heat, shock or pressure induced transfer warmed up. from a wax-coated carbon paper or 5. The method according to claims 2 or 3, thereby 30 another transfer sheet, are generated, characterized in that a transfer sheet is water-soluble or hydrophilic coatings, e.g. B. off used, in which the »-naphthol only in the dichromate containing colloid or from diazo resin, image-wise areas are present, and these can thereby be made dye-receptive, for the transfer of the naphthol uniformly it is necessary to expose them to a photograph. Furthermore can warms. 35 oily or waxy or polymeric inclusions in 6. The method according to claim 5, characterized in that the transfer sheet is influenced by pressure or heat so that it is available by means of reflective exposure of a graphic original on the surface, a hydrophilic coating by local application,
forms actinic radiation, the transfer of reactants from a transfer sheet initially a uniform coating 40 exposed photosensitive transfer sheet on a "-naphthol as well as light-reducing- a recording sheet which has an image-forming dye, so that the" -Naphthol contains reactants as a second reactant, in combination with the dye by the acti- has previously been proposed, e.g. B. is desensitized according to image in the niche radiation. U.S. Patents 3,094,417 and 3,094,619. Under 7. The first reactant is applied to the lithographic printing plate for performing the reflex exposure tion of the method according to claim 1, characterized in that the reflective base areas are non-reactive, that it is made capable of a hydrophilic printing layer, but exhibits a small part of the reaction, on their surface an ionic iodide means that over the light-absorbing image areas is present as a reactant. of the original remains unchanged. The warming 8. The lithographic printing plate of claim 7, 50 of the exposed transfer sheet under assembly characterized in that the ionic iodide against a receiving sheet then leads to a reaction is an organic compound. with the reaction partner and causes the development 9. A lithographic printing plate according to claims with a corresponding image on the surface 7 and 8, characterized in that the take sheet from. This process is shared with other clubs Ionic compounds consisting of organic compounds are described in German Patent 1,263,032 as Iodide is a quaternary ammonium iodide. a method of forming oleophilic image areas 10. A lithographic printing plate according to an on a lithographic plate, which has a reducible claim 7, characterized in that the iodide metal salt, such as Kiipfer (II) nitrate or iron (ni) nitrate, in an amount of about 0.025 to 2, 5 g / m ^{2 in} front as a reactant, proposed, which is tied. 60 metal salt to vain oleophilic imaging material 11. Lithographic printing plate is reduced after contact. claim 7, characterized in that it is from The invention is now based on the object of a a paper base and a coating from a process for the production of a lithographic a hydrophilic water-binding agent! tiiid FiaGhdrugfcform zu sGhgffeir which allows many a hydrophilic fine vc. divided filler consists of 65 thousand prints without degradation of the image quality which also contains water-soluble ionic iodide. or the opacity. 12. Lithographic printing plate according to An. This object is achieved according to the invention by a Claim 11, characterized in that the greatest method of manufacture: a lithographic