DE2708689A1 - ENDLESS OFFSET PRINTING SYSTEM - Google Patents

Description

MÜLLER-BORA · DlSlFiSJL · SCHÖN - HKRTEL

DR. WOLFGANG MÜLLER-BORE (PATENT ADVOCATE FROM 1927 - 1975) DR. PAUL DEUFEL. DIPL.-CHEM. OR. ALFRED SCHÖN. DIPL.-CHEM. WERNER HERTEL. DIPL.-PHYS.

Munich, * Feb. 8, 1977 Hl / ma - T 1379

TOKYO KIKAI SEISAKUSHO, Ltd.
26-24 Shiba 5 Chome, Minato ku, Tokyo / Japan

Continuous offset printing system

The invention relates generally to a continuous printing system, and more particularly to an offset printing system, its plate cylinder and / or offset cylinder is improved so that continuous printing is possible.

In general, an offset printing system has a plate cylinder, an offset or blanket cylinder and a printing cylinder. If with such an offset printing system working with direct lithography is not a

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Offset cylinder required, as the printing plate of the plate cylinder For example, a plate obtained in the following manner is generally used: by planographic plate-making a printing surface is formed on the flat surface of a metal plate; the the resulting printing plate is attached to the plate cylinder by the opposite ends of the printing plate can be inserted into the matching grooves in the plate cylinder. Similarly, the Offset surface of the offset cylinder made by a blanket is attached tightly to the offset cylinder; to this are also the opposite Ends of the blanket inserted into corresponding grooves in the offset cylinder. The one in the plate cylinder and matching grooves formed in the offset cylinder, however, lead to partial discontinuities or Discontinuities in the plate surface or the offset surface and prevent the printing from being performed on the entire surfaces. this applies also for a system that works with direct lithography. Because these discontinuities in the printing surface are not are to be avoided, it was previously not possible to use offset printing to create a continuous pattern or pattern. To print stencil and other forms of continuous printing. This is also the reason why Endlosdrutk has so far only been carried out in gravure printing. However, compared to offset printing, gravure printing has the disadvantage that the panels are extremely expensive to manufacture and require a great deal of time and labor requires because the printing surface on the plate cylinder must be produced by a complicated process, that consists of the following steps: the plate cylinder is galvanically provided with a copper coating; a certain original is printed on this surface in such a way that the tone changes of letters, figures,

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ren or patterns of the original in the form of changes in depth of a corrosion-resistant membrane (a photosensitive membrane consisting essentially of gelatin); then the surface the copper layer is provided with a coating, after which the copper surface by the corrosion-resistant Membrane is geifet so that on the copper surface a relief is created; Finally, the copper surface provided with the relief is electroplated provided with a chrome coating. For this reason, gravure printing is only an economical process when the number of prints made with it is extremely large. Now, however, everyone has their own Taste in relation to printed matter, so it is necessary to have a wide variety of printed matter manufacture to meet each different requirement. Under these circumstances, the Production of printed matter using the rotogravure printing process can hardly be paid for. As a result, it is currently pulling planographic printing is once again attracting the attention of the industry.

In addition, the following applies: if the printing process is to be switched to a new original, it is with gravure printing absolutely necessary, the existing, chrome-plated copper printing surface of the plate cylinder remove and create a new printing surface by doing all of the above, extremely complicated Process steps, beginning with the production of a copper layer by galvanic method, are repeated will.

It is therefore an object of the present invention to improve the plate cylinder and / or the Offset cylinder in a conventional offset printing press

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Se to create a printing system that enables continuous printing and with which the printing process is also easy a new original can be converted by removing the previously used printing area from the plate surface scraped off and then provided with a new printing surface, which can be seen without any difficulty on the Can form plate surface.

So far, various measures have been proposed to deal with the area with the partial discontinuities to compensate or improve in the printing surface of the offset surface of the offset printing press; this includes for example, an endless printing plate made of a cylindrical body and offset cylinders with endless offset areas consisting of two usual plate cylinders are formed. However, the first-mentioned proposal is unrealistic as there is only one procedure Proposed for the production of a printing surface and not the method is explained how this printing surface to can be attached to the plate cylinder or how easily the printing surface for a new original can be produced. A disadvantage of the last-mentioned proposal is that there is water and the Ctoick color deposited twice on each of the offset cylinders must be, the ink deposited in the second cycle will always be transferred to the water layer, which was formed in the first cycle; in addition, the ink density in the deposited ink layer becomes unevenly distributed so that there is no clear print.

So far, an offset printing system could not be used for continuous printing; this is solely on it attributed to the long-established general Concept that the offset

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Printing is linked to a mechanical limitation, namely that of the plate cylinder and that of the printing surface forming printing plate can be produced independently.

In the case of the present invention, this principle, which has long been used and recognized, is completely abandoned, so that even with an offset printing system, continuous printing can be done by coating the entire periphery of the plate cylinder with a hydrophilic metal so that hydrophilic areas are formed on the printing surface; on these hydrophilic areas deposited oleophilic areas by any of the processes known for the manufacture of planographic printing plates, which are to serve as pressure areas; then the resulting offset plate cylinder is attached to the corresponding Place on a standard offset printing press.

In the offset printing system according to the present invention, since the printing surface is formed endlessly on the entire peripheral surface of the plate cylinder without any partial discontinuities occurring therein, printing of a continuous pattern or stencil and other forms of continuous printing can be carried out; After use, the printing surface, which contains the image of an original, can easily be removed and a new original can be applied in its place. This offset printing system contributes so for economic use in the media. However, since the offset plates can be produced at a cost low enough to reduce the cost of plate production very much, the offset system of this invention enables a significant reduction in the price of such printed matter such as wallpaper,

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Objects that contain woodgrain prints or prints as well as printed matter.

The invention thus provides a continuous printing system with which continuous patterns and other forms of continuous printing Can be printed by using an offset plate cylinder is produced with an offset printing surface, which is formed in the endless state directly on the entire peripheral surface of the plate cylinder itself; the resulting offset plate cylinder is sent to the corresponding Place attached in an offset printing press. The offset printing surface is in the endless state directly on the Circumferential surface of the plate cylinder itself from the same Material formed like the plate cylinder and attached to the circumference of the plate cylinder.

The invention will be described in the following on the basis of exemplary embodiments with reference to the accompanying schematic Drawings explained in more detail.

Show it:

Fig. 1 is a partially cut-away front view of a plate cylinder which is an essential Figure 3 represents a component of the device according to the present invention;

Fig. 2 is a cross-sectional view of the state in which the plate cylinder of FIG Location in a printing system;

FIGS. 5 through 5 are overall side views of preferred embodiments of the present invention, where Fig. 3 shows an embodiment of the offset

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Type, Fig. 4 shows an embodiment of the direct printing type and Fig. 5 represent an embodiment that the offset printing system according to the present invention combined with a conventional gravure printing system;

Fig. 6 is an explanatory diagram showing a method of coating the plate cylinder with a light sensitive liquid, Fig. 6 (A) referring to the Application by the roll coating method and Fig. 6 (B) relates to the application obtain by a dip coating process; and

7 is an explanatory diagram showing a method of printing an original " films on the printing surface, with Fig. 7 (A) relating to the printing by the The wrap-around technique and Fig. 7 (B) relate to the printing by the Refer to the film-belt technique.

The invention will be explained in more detail below with reference to the accompanying drawings. The one you want Continuous printing is performed by the plate cylinder according to Fig. 1 and an offset printing press, tfie it is shown in Fig. 2 can be used in combination; the plate cylinder is shown in FIG Position attached. The continuous printing can be by the offset method, as shown in Fig. 3, or can be performed by direct printing as shown in FIG.

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The plate cylinder 1 made of cast iron has a combination of the actual plate cylinder 3 and sleeves or sockets 5, which are integral with fastening axes 4 are formed; the actual plate cylinder 3 is designed so that on it one Pressure surface 2 is formed. The actual plate cylinder 3 and the bushings 5 can be made in one piece by casting or be manufactured integrally. As can be seen from the illustration, a wall 6 can be attached to each the opposite ends of the actual plate cylinder 3 may be provided; the sleeves 5 can be removed be attached to the walls 6 with the aid of bolts or screws 7. There is also an offset cylinder 8 and a pressure cylinder 9 is provided. The entire peripheral surface of the offset type offset cylinder 8 and the entire Circumferential surface of the printing cylinder 9 of the direct printing type are each endlessly coated with an elastic element 10, which consists, for example, of rubber, In addition, a device 11 for supplying the printing ink, a device 12 for supplying the water and a material 13 is provided which is to be printed with copies of the original.

So that the hydrophilic areas of the printing surface 2 can be formed, the surface of the actual Plate cylinder 3, which is formed by a hollow cylinder made of cast iron, galvanically with provided with a layer of rigid chrome; as an alternative to this, it can be fused with a sheet-like structure or sheet or sheet of stainless steel are coated, followed by a high-gloss polish is carried out; then the resulting surface is honed by pressure blasting or sandblasting treated so that the high-gloss polishing surface is fine-grained or becomes rough. These surface treatments are supposed to

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improve the water absorption capacity of the surface and cause the photosensitive liquid to adhere quickly. After these surface treatments, the Printing surface 2 by any of the known methods of making planographic printing plates directly on the whole Surface of the actual plate cylinder 3 formed, which has previously been roughened.

The plate-making can be carried out, for example, by the following method.

(1) Production of the surface:

The surface of the actual plate cylinder 3 is cleaned using a degreasing agent from Removes oils and fats or lubricants that stick to the surface; then the area Washed thoroughly with water and in preparation for the subsequent printing step in the appropriate Treated wisely.

(2) Application of the photosensitive liquid:

On the entire surface of the actual plate cylinder 3, which in the manner described above has been prepared, the photosensitive liquid, which is the composition suitable for offset printing applied by roller coating or by dip coating. With roller coating must the actual plate cylinder 3 with the help of rollers with the photosensitive liquid coated, which is located in a bath; the rollers are designed so that they are in rolling contact can be brought with the cylinder surface as shown in Fig. 6 (A). In the Dip coating, the light sensitive liquid is applied to the actual plate cylinder,

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putting one with the photosensitive liquid Filled bowl or drip tray brought into rapid contact with the plate cylinder at one end whereby the plate cylinder can move downward while the plate surface is in sliding contact with the inner edge of the drip tray.

The photosensitive liquid is in two Types available, one type for positives and the other type for negatives. Generally used the first-mentioned type is a photo-soluble resin and the last-mentioned type is a photo-curing one Resin. After the application of the photosensitive liquid, the actual plate cylinder becomes Left to its own devices in a hot air stream or exposed to heat rays. As a result the photosensitive liquid forms a photosensitive liquid Film that quickly adheres to the entire surface of the plate cylinder 3 proper. This photosensitive film forms oleophilic areas the printing area when subjected to printing of an image in an original film, such as will be described below.

(3) Print of the original film:

A negative original film in which the photosensitive Film is made from a negative photosensitive liquid, or positive original film, in which the photosensitive film is obtained from a positive photosensitive liquid is held tightly against the photosensitive film surface; Light of one wavelength, which is suitable for sensitization is shown by the original film on the light-sensitive

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is projected onto the film, which copies the original onto the photosensitive film. The ones in very good Contact application of the original film to the surface of the photosensitive film and the subsequent copying of the original can be carried out either by the winding method or by the film belt method be performed; In the winding process, the original film is transferred directly by means of a Pressure roller against the surface of the photosensitive Film is pressed, with light from a suitable light source passing through the tight-fitting original film is projected on the surface as shown in Fig. 7 (A); in the film belt method the original film is formed in the endless state, with the endless original film in close rolling contact with the surface of the photosensitive film on the surface of the plate cylinder proper 3 is brought; at the same time, the photosensitive film is exposed or exposed to light through the original film. exposed as shown in Fig. 7 (B).

(4) Development:

A developer for the negative, photosensitive Film or for the positive, photosensitive film - it depends on which one Film type is used - is applied to the photosensitive film so that the unexposed Areas in the negative photosensitive film or the exposed areas in the positive photosensitive Film can be extracted. Then the photosensitive film is washed thoroughly with water. Then a ball of cloth or cloth, which is impregnated with an offset printing ink, is applied to the The surface of the photosensitive film is bumped to ensure that the graphic Representation between the pressure (oleophilic) areas

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and the non-printing (hydrophilic) areas of the printing surface corresponds exactly to the original. Then the plate making is brought to an end by removing the adhering Offset printing ink with a liquid for treating an offset printing surface from the copy is wiped off.

In general, the printing area will be 2, with all of the above Process steps described have been carried out with a dilute gum arabic solution as Protective layer until it is actually used for printing.

The plate cylinder 1 thus contains the offset printing area 2 formed as a result of the method described above; this plate cylinder 1 is then on attached to the corresponding point of an offset printing press and used for continuous printing. The exact The position of the plate cylinder in the printing press depends on various circumstances; at an offset printing press the plate cylinder becomes close to the offset cylinder 8, the device 11 for supplying the printing ink and the device 12 for supplying the water; in a direct printing system, the plate cylinder is in the vicinity of the impression cylinder 9, the device 11 attached for supplying the printing ink and the device 12 for supplying the water; be there each its pods. 5 supported in their respective bearings 15 so that the plate cylinder is in rolling contact with these parts is located. When the printing press is started, each device 11 feeds printing ink or the device 12 supplies water to the pressure surface 2. On the printing surface 2 forms the area of the photosensitive Film that has withstood the action of the developer, the oleophilic (print) areas, while the other

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ren areas that have been dissolved out by the developer, the hydrophilic areas in which the Hard chrome plate or another hydrophilic, deposited on the surface of the actual plate cylinder 3 Metal plate exposed to light rays or exposed. Form the oleophilic areas of the pressure surface the pressure areas. The printing ink supplied by the device for supplying the printing ink is only applied to the oleophilic areas of the printing surface and not transferred to the hydrophilic areas that hold back water or record. On the printing material 13 to be printed on, the printing ink is only used by the Transferred oleophilic areas (namely the pressure areas) of the plate surface. This is how offset printing works carried out.

Very aesthetic prints can be obtained by using the offset printing system of this invention with a conventional gravure plate cylinder 14 combined as shown in FIG. This results in the following mode of operation: if a certain Area of the surface of the gravure plate cylinder 14 is masked, such as with a suitable Painting, so that this surface can continue to repel the printing ink, can be done by the offset printing press a suitable pattern can be printed in the corresponding free space on the printing material. The combination enables the production of extremely attractive prints for a wide variety of flavors.

When the printing is finished, the printing surface is treated with a solvent (release agent), so that the areas of the photosensitive film which form the printing areas of the plate surface, through the Solvent to be dissolved. The dissolved film

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containing and adhering to the surface of the plate cylinder release liquid is by a suitable Solvent such as toluene removed thoroughly. Then the surface of the plate cylinder washed extensively with water. As a result of this surface treatment the surface of the actual plate cylinder 3 is restored to the state it was in before production the printing plate was present. When a new original is fed for another printing, the plate-making process described above with steps (1) to (4) must be repeated in order to be in the printing area to produce oleophilic (print) areas that correspond to the pattern of the new original "; however, it must Don't repeat the complicated process that involves applying a copper layer galvanic path begins, as is the case with relief gravure printing.

The structure of the plate cylinder 1 is designed so that the actual plate cylinder 3 is easily removed from the offset printing press can be removed by just unscrewing the screws. If the rough or granular, on the entire circumferential surface of the actual plate cylinder 3 formed surface is worn after prolonged use, it can easily, for example by honing with a pressure jet, so that a new rough or honed surface is available.

The present invention is described in detail with reference to the accompanying drawings been. As is apparent from the description, the plate surface containing a new original can easily are made while the surface of the plate cylinder is kept intact. The present invention thus contributes significantly to an economic use

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of materials for the actual printing process and enables continuous printing with an inexpensive Offset printing plate can be done. As a result, prices can be different, through Endless printing of products obtained are significantly reduced, such as, for example, the stencils or matrices or transfer printing mirrors, which are used for printing fabrics or cloths, decorative or decorative cardboard or stiff paper, patterned papers such as those used in ceiling surfaces, and wallpaper. Thus, the advantages of the present invention are both economic and industrial Area.

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Claims (6)

Claims Endless offset printing system for printing a continuous Patterns and other similar forms of continuous printing using an offset printing press, characterized in that an offset plate cylinder in an offset printing press (1) is installed, for the production of which the entire circumferential surface of a plate cylinder (3) is coated with a hydrophilic material in the endless state to have hydrophilic areas thereon To form the pressure surface, and then oleophilic areas that are to serve as pressure areas of the pressure surface (2), by one of the known processes for the production of planographic printing plates, on the surface of the hydrophilic metal are formed. 2. Endless offset printing system according to claim 1, characterized in that that chromium or stainless steel is used as the hydrophilic metal, and that the whole Circumferential surface of the plate cylinder (3) in the endless State is coated by either applying chromium by electroplating or a flat structure stainless steel is attached to it by fusing. 3. Continuous offset printing system according to one of claims 1 or 2, characterized in that the production -17- 709835/1012 ORIGINAL INSPECTED the planographic printing plate on the entire surface of the hydrophilic material is carried out after this surface has been subjected to a treatment is to form a fine-grained surface thereon. 4. Continuous offset printing system according to one of claims 1 to 3, characterized in that the plate cylinder (1) is an actual plate cylinder (3) which consists of consists of a hollow cylinder and opposing circular walls, and has sleeves (5), which are formed in one piece with fastening axles, the sleeves being removable by screws on the walls are attached. 5. Continuous offset printing system according to one of claims 1 to 4, characterized in that the offset printing press containing the plate cylinder (1) for the Offset printing is used by providing an offset cylinder therein, the entire peripheral surface of which is coated with an elastic substance in an endless state. 6. Continuous offset printing system according to one of claims 1 to 4, characterized in that the offset printing press containing the plate cylinder (1) for the direct printing is used by no offset cylinder is used and a pressure cylinder is provided, - 18 - 709835/1012 its entire circumferential surface with an elastic Substance is coated in the endless state. 709835/1012