DE2413743A1 - PADDED PRINTING PLATE LAMINATE AND THE METHOD OF ITS MANUFACTURING - Google Patents

Description

G-aineBvi.il e, Georgia /V.St,A.

Our reference: W 889

Padded printing plate laminate and method of making it

The invention relates to a padded printing plate laminate and a method for its production.

With the progressive improvement in the quality of printing facilities Tighter tolerances are also required for the flexible printing plates, which are used in conjunction with such Facilities are used. As the speed of the printing devices increases, there is also a tendency that the plate cylinder carrying the printing plates impacts in an undesirable manner when the trailing edge of the printing plate comes together with the printing cylinder or the document cylinder due to the medium to be printed

Because it has proven difficult for the printing facility required close tolerances in forming the printing plate and in securing the same are to be maintained

Dr.Hn/ju

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Various attempts have been made to make a printing plate capable of a wider dimensional tolerance at the pressure plate to compensate at the same time. Maintaining good print quality and which ones absorbs the high-speed impact effect · One of these Attempts consisted in using the usual double-sided adhesive backing, known as "stickyback", to be replaced by a sponge rubber pad, its opposite sides with a pressure-sensitive (self-adhesive) adhesive are coated. It is true that the desired tolerance compensation was achieved in this attempt can be achieved at the start of work, but various problems have arisen, including the widespread Have prevented use of the same

One of these problems is that the cushioning material used did not have the necessary elasticity, so that the material between the impressions a printing device did not fully recover or spring back, causing a permanent Deformation arises which reduces the effectiveness of the cushion · Another problem is that it is difficult is to find an adhesive that will prevent the lifting of the pressure plate prevented during operation. Another problem is that due to the fact that the strength of the Padding material is relatively small, it is practically impossible to remove it from the cylinder plate without destroying it, when a print job is finished · But even if the cushioning material is destroyed when removing it, one is such removal is unduly time consuming and renders use of strong solvents, which attack the neighboring printing plates on the same printing cylinder can. Another problem is that those for use in color solutions (printing color solutions) are solvent-based required solvent at a fast

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Impairment (deterioration) of the upholstery material, so that it becomes unusable

These and other problems and disadvantages are overcome according to the invention in that a padded or resilient (elastic) print laminate has been found that not only has good printability over a wide tolerance range and has a good absorption capacity for chocolate, but also does not accept any permanent deformation during pressing in addition, this virtually eliminates the separation, attachment and removal of the pad from the pressure plate of the laminate is lightened while maintaining the same solvent resistance as conventional printing plates will. In addition, the padded laminate of the invention is attached and handled in the same way like a conventional printing plate so that no special equipment or procedures are required. To adjust its thickness, the same grinding process can be used on the laminate as with conventional ones Printing plates can be applied.

The laminate consists of a first layer of a simple one (pure or unmixed) rubber races on which the printing elements are formed, and a second layer from a rubber compound in which a foaming agent is dispersed is. The foaming agent foams the second layer during the simultaneous curing of both layers from the rubber compound in a printing plate molding press.When the layers harden, they are also vulcanized together, so that the laminate obtained thereby represents a unit. Behind the second layer can be a third layer of a be arranged simple (pure) rubber compound, which serves as a base (carrier) for the laminate and with the other Layers is hardened.

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The first layer is prepared in the usual way, while the second layer with the foaming agent dispersed therein, for example an azo compound, an ff-mtroso compound, a sulfonyl hydrazide or an inorganic one Carbonate, by mixing, and then calendering the mixture or only by calendering. the Layers can be calendered on top of one another or they can be placed on top of each other separately in a compression molding press then heat and pressure are applied to the compression molding press, to first foam the second layer and then cure the layers to form the printing plate laminate.

These and other features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention in conjunction with the accompanying drawings. In the accompanying drawings, like parts are used marked with the same reference numbers. They show:

Fig. 1 is a perspective view of the printing laminate of the invention mounted on a plate cylinder is;

Figure 2 is a partial cross-sectional view of an embodiment of the invention after curing;

FIG. 3 is a partial cross-sectional view of that shown in FIG Embodiment of the invention before curing;

Figure 4 is a partial cross-sectional view of another embodiment of the invention after curing;

Fig. 5 is a schematic diagram showing the manufacture of the printing laminate according to the invention explained;

6 is a perspective view of a printing plate molding press; which the production of the invention

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Laminate explained;

Pig. 7 is a diagram showing the hardening according to the invention - cyelus explains

The accompanying drawings and the following detailed Descriptions illustrate specific embodiments of the invention; however, it will be apparent to those skilled in the art that the invention is not limited to this, but that the illustrated or described preferred embodiments in many respects can be changed and modified without departing from the scope of the present invention.

In the figures of the accompanying drawings, there is the hardened Printing plate laminate 10 generally consists of a top layer 11 which rests on a cushion layer 12. The laminate 10 is in a conventional printing device (printing machine) by known methods, for example by means of a Adhesive back or by fastening on a magnetic base mounted on a plate cylinder PO.

The top layer (cover layer) 11 is made using common rubber compounds as they are currently used for the production of conventional printing plates. Although the Various rubber stocks are available, some of the more common stocks are the natural rubbers, nitrile, vinyl and other synthetic rubbers · All of these rubbers can be inside des in a conventional molding press or in a vulcanizer, as is currently used for molding and hardening conventional Printing plates are used, the available temperature and pressure range are hardened The raised (protruding) Printing elements 14- are on the outer surface side 15 of the Layer 11 is provided, while the cushioning layer 12 is pressed onto the rear side 16 of the layer 11

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The cushion layer 12 is during the curing of the laminate has been foamed with a foaming agent or blowing agent. The layer '12 is made using a conventional one Gtunmimasse like layer 11, with the exception that the layer 12 contains a foaming agent, which before Forming the laminate and uniformly dispersed therein prior to curing. The foaming agent will gasified or puffed up during hardening, causing the closed ones indicated in Pig · 2 by the numeral 18 Cell cavities arise within the cushioning layer 12. It should also be noted that the layer 12 is thicker Section 19 under each outer raised pressure elements 14 and a thinner portion 20 under the non-printing or dead areas of the topsheet 11, the manufacture thereof The cavities 18 make up about 1/2 to about 3/4 of the volume of the layer 12.

Since only the printing surface 21 of each of the raised printing elements 14 with the inking roller of the printing device and the to printing substrate comes into contact when it rests on the printing cylinder, only this area under the needs raised elements 14 to be essentially padded or sprung (elastic) · Also by reducing the thickness of the foamed Layer 12 in the Mcht-print or dead areas becomes the lateral stability of the elements 14 and the print surface 21 each guaranteed. In this way there is a uniform contact between the printing surfaces 21 and the Inking roller, so that the desired uniform coloring of the surfaces 21 is maintained, as well as the contact ensured between the surfaces 21 and the substrate to be printed when it rests on the printing cylinder, so that the substrate is printed evenly. Although the sections 19 can have varying thicknesses, they will be good ones Results obtained when sections 20 are 0.038 to 0.127 cm (0.015 ms. 0.050 inch) thick · The sections 20 should be as thin as practical, but good results are obtained if the thickness of the sections

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20 1/2 Ms 2/3 the thickness of the sections 19 is

The laminate 10 before curing is in the pig. 3 explains · The layer 12 has discrete particles of the foaming agent evenly dispersed therein, which are indicated by the number 22 · The layers 11 and 12, which are of the same size, lie on top of one another and can be calendered together or they can remain separate until hardened The layer 12 can be colored differently than the layer 11 _{1 in} order to facilitate the identification of the layers, especially if the layers are calendered together for curing before they are placed on top of one another in an insert (oven insert).

A wide variety of foaming agents 22 can be used, but it must be capable of operating within the curing temperature range of the rubber composition of layers 11 and 12 to pass into a gas or to puff and it should be essentially gasified before any substantial hardening of the Rubber mass takes place «The foaming agent or blowing agent 22 is a thermally unstable chemical compound that is formed when Heating to the curing temperatures of the rubber compound decomposes, releasing a gas and leaving behind one inert residue. The gas release is controlled (regulated) by choosing the appropriate chemical or by adding activators to keep it up with the initial rise of the Module of the rubber mass collapses, causing the gas bubbles in the vulcanized rubber mass are held and a allow maximum expansion · A bheometer diagram which the relative curing times illustrated is shown in Fig. 7, the diagram (the curve) of the top layer represented by a dashed line and the diagram (curve) of the cushion layer represented by a solid line are.

Some types of foaming or blowing agents 22 that

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can be used according to the invention are the following:

Azo compounds

Azodicarbonamide • O j1'-azobisformamide) Azobis (isobutyronitrile) diazoaminobenzene

Decomposition temperature range in

⁰ C ( ⁰ F) 149-204 (300-400)

84.4-115.4 (194-239) 93-99 (200-210)

Gas yield in ml / g / with STP

220

130 115

N-nitroso compounds

N, B - dimethyl-] J, B - · -dinitroterephthalamide

N, N ¹ -Dinitrosopentamethylene ^ tetramine

Sulfonyl hydrazides

Benzene sulfonyl hydrazide p-ioluene sulfonyl hydrazide

Diphenylsulfon-3,3'-disulfonylhydrazide

ρ, ρ'-oxybis (benzenesulfonyl) hydrazide

inorganic carbonates sodium bicarbonate

82-104 (180-220) 125 Ϊ3Ο-Ι9Ο (266-374) 265 99-104 (210-220)
99-110 (210-230) 130
111 130-150 (266-302) 110 127-150 (260-302) 125

99-116 (210-240)

In general, organic compounds provide a foam layer 12 with closed cells, while inorganic carbonates form a foam layer 12 with open cells (interconnected Cells) provide · Although the percentage of foaming agent 22 in relation to the rubber mass can vary in Depending on the gas yield of the foaming agent, it has been found that a layer 12 is satisfactory which contains about 3 to 6 vol .-% of the foaming agent, des-

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sen gas yield is in the range of 100 to 150 ml / g *

Although it is not necessary that the rubber weights of layers 11 and 12 be the same so long as they are both within the same temperature range and harden within the same time, the rubber masses are preferably the same, to ensure a simultaneous complete curing of both layers to ensure that sufficient Bonding of the layers to one another takes place, and to ensure that the resistance of both layers against Solvent attack is the same · Because layer 12 is made of a rubber compound, recovery or springback occurs of layer 12 after being compressed by the impression cylinder while in contact with the substrate of the elements 14 for printing practically immediately, so that no permanent Deformation occurs

In Fig. 4 is a second embodiment of the laminate shown, which is designated by the numeral 10 '. Because some of the components of the laminate 10 * are identical to those of the laminate 10, they are. Components through the the same numerals as in the laminate 10. The laminate 10 * also includes a backing layer 30 that is bonded to the side of the cushioning layer 12 that is the The layer JO serves to keep the layer 12 sufficiently close to the pressure elements 14 to ensure good padding of the elements and also good firmness of the back side of the laminate 10 'to ensure that it can be dismantled from the plate cylinder again without damage. To the Production of the backing layer (backing layer) 30 can Different materials are used in the enclosed r the drawing shows a rubber compound that is satisfactory Delivers results. It should also be noted that the pad is a metal pad or a 'magnetic Can be underlay. The rubber compound shown is the same as that used for the topsheet 11

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to ensure a good bond between layers 30 and 12, while layers 11, 12 and 30 in be hardened in a compression molding press. The topsheet 11 should preferably be as thin as possible, but still sufficient Flow during the deformation and hardening ensure the correct shaping of the pressure elements 14 to ensure. - ·.

Because of the inherent resistance to movement between the raised pressure elements 14 and the dead area of the unfoamed Layer 11 was found to increase both the amount of cushioning and the rate of recovery (rebound rate) of the printing surface 21 of the elements 14 somewhat -dependent on the thickness of the layer 11. Satisfactory results are obtained when the cushion layer 12 within 0.025 *> is 0.127 cm (0.010 to 0.050 inch) of the printing surface 21 of the elements 14 is.

It has also been found that the cushion layer 12 prior to hardening of the surface layer 11 and the backing layer 30 can be hardened and foamed separately. The hardened one Padding layer 12 is then placed between the uncured surface layer 11 and the backing layer 30 forming a filling (insert) and the filling is hardened in the usual way to form the laminate 10 or 10 '. The laminate obtained is practically the same. Cross-sectional configuration as shown in the figures 2 and 4, in which the cushion layer 12 under the pressure elements 14 in the surface layer 11 is thicker Sections 19 and under the Mcht-pressure areas of the surface layer 11 has thinner sections 20. The mode of action (performance) of this laminate is practically the same like that of laminates 10 and 10 *

5 shows the production of the uncured layers 12 explained. The foaming agent can be in layer 12

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be dispersed by first mixing the foaming agent in powder form with the rubber compound in a conventional mixer M and then calendering in a calender mill 0 to the final size indicated by dashed lines in FIG. 5 or by adding the already dispersed foaming agent in a high concentration in a gum compound, as indicated at D in Fig. 5, and this is then calendered with another simple (pure) gum compound, as indicated at G in Fig. 5, in the mill C, as shown by the solid lines, for production the right dispersion. After properly dispersing the foaming agent in the layer 12, it can be rewound on a roll at a winding station W, as shown in dashed lines in Fig. 5, or the uncured layer 11 can be in a mill G ^ without any dispersion between the layers are calendered thereon and the composite of the layers 11 and 12 can be wound up at the winding station Wp, as shown in FIG. 5 by solid lines. It should also be pointed out that the uncured backing layer 20 can also be calendered onto the composite. The roll from the layer 12 of the winding station W or the roll from the composite consisting of the layers 11 and 12 of the winding station W is then usually sent to the plate manufacturer, who deforms and hardens the layers to form the printing plate laminate 10 or 10 .

The plate manufacturer uses a conventional printing plate press or a vulcanizer V, as shown, for example, in FIG. 6, to produce the laminate 10 or 10 ¹ . The preparation of the load (filling) for the press is similar to that as it is currently used. If the layers 11 and 12 are picked up separately, the uncured surface layer 11 is first cut to such a size that it just makes the impression of the matrix types MX covered and is placed on the die · Then the uncured .upholstery layer 12 is cut to such a size that it just covers the already applied layer 11 · The panel manufacturer

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then determines if any additional gum compound is required is to achieve the correct height for the filling and, if necessary, place it over the layer 12 »If the Layers 11 and 12 are already calendered together, the panel manufacturer simply cuts the composite to such a size that it just covers the die MX, and lays the composite on the die in such a way that the surface layer 11 is above the indentation (depression) on the die. Then, on the back of layer 12, as above explains how the additional rubber compound required to complete the filling is applied · The supports or side irons B are then selected to correspond to the total desired thickness of the laminate 10 and they are customary Way, as in Pig. 6 shown, arranged. A paper or metal cover sheet is placed on the entire filling (loading) CS and carrier B placed in order to prevent the formed laminate 10 from sticking to the cover plate of the press V during curing sticks.

The filling (charge) is then introduced into the conventionally preheated press V and the filling is then subjected to heat and pressure within the time and temperature range prescribed for the rubber compound "of the layers. In the Hegel, about 8 to about A heated for 12 minutes at etv / 14-9 to about 155 ° C (300-312 ⁰ F.). in general, the curing of the rubber composition begins after about 3 minutes in the press and is completed in about 8 minutes · the foaming agent begins typically gas or puff itself in about 1 minute in the press and it will be completely gasified in about 3 minutes in the press The fact that the foaming agent is gasified before hardening essentially begins serves to provide sufficient flow ensure within the rubber mass of the layer 12 to prevent destruction of the layer, while at the same time the surface layer 11 partially in the impression (Recess) is pressed on the matrix MX, so that the thicker sections 19 in the

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Layer 12 formed under the finished molded elements while the thinner sections 20 are formed where the mattress supports the layer 11 in the districts, which become dead areas in the finished laminate 10

The thickness of the layer 12 is generally controlled by the distance between the platens of the press V and the thickness of layer 11 as well as any backing layer applied to the back of cushion layer 12 during layup is · In general, the layer sequence (stacking) of the filling or loading is the same as with the usual Printing plate production, but with the exception that the filling is an uncured Po 1st layer 12 has. The excess Parts of the initially uncured layer 12 are ejected as the overflow during the molding

Although the thickness of the uncured surface layer (top layer) 11 can be varied, need for good. Formation and good operation of the laminate are two factors to consider * - be required: the first is that the visual layer 11 must be thick enough to allow sufficient flow of the rubber compound during molding to ensure the pressure elements 14 · correctly form, and the second is that they are attached to the Printing elements must be thin enough to ensure that the cushioning effect of the layer 12 on the printing surface ^ edes of the elements is transferred. Satisfactory results are obtained using a layer 11 with an uncured one 0.051 to 0.152 cm (0.020 to 0.060 inch) thick.

The thickness of the cushioning layer 12 is determined by the desired cushioning. If the thickness is too great, then the printing elements 14- are not stable enough to achieve good print quality.Although this thickness can be varied, good results are obtained using a layer of uncured thickness of about 0.0635 cm (0.025 inch) _t the hardened thickness of the sections 19 of about

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0.0 $ 81 to 0.127 cm (0.015 to 0.050 inch) gives · Let be pointed out that the uncured layer 12 must have exposed edges so that that formed during foaming excess material escape and from the finished Laminate can be trimmed.

When the backing layer 30 is applied, it becomes used to complete the overall thickness required for the laminate 10. Layer 30 is in the filling ((Charging) laid and hardened at the same time as layers 11 and 12. In the Hegel, the thickness of the unhardened is Layer 12 about 0.076 to 0.152 cm (0.030 to 0.060 inch) when the finished laminate 10 is to have a nominal thickness of 0.318 cm (0.125 inch). These thicknesses can be more suitable Ways to be varied if the finished laminate has a nominal thickness of 0.229 cm (0.090 inch) or 0.635 cm (0.250 inch) as it is sometimes required.

It should be noted that the hardening remains the same as with the conventional printing plates, so that no additional Personnel training is required · In addition, the cushioning layer 12 is removed during the stacking handled exactly like any other piece of a common rubber compound for molding · Also the finished laminate 10. or 10 · can be attached and checked like a conventional pressure plate.

Alternatively, the uncured cushioning layer 12 can be individually cured so that the layer 12 is foamed to the prescribed thickness. This can be done in a conventional compression molding press or carried out in a vulcanizer by suitably adjusting the thickness of the supports or side irons. There the hardening and foaming of the layer 12 takes place much faster than the normal hardening of a simple (pure) rubber compound, the hardening time can be appropriately reduced will.

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The final feed for the laminate is carried out in a similar way, as already described. The uncured surface layer is cut to the appropriate size and placed on the matrix MX of the compression molding press V · Then For example, the cured cushion layer 12 is cut to the appropriate size and placed on the uncured surface layer 11 placed. Then the backing layer 50 is coated with the appropriate Thickness cut to the correct size and placed on the hardened cushion layer 12

The carrier or side iron B are then selected so that they correspond to the desired total thickness of the laminate and they are arranged in the usual manner as shown in FIG. On the entire load and the carriers B a paper or Metal cover sheet OS placed, uia to prevent the laminate formed during curing on the cover plate of the press V sticks.

The charge is then introduced into the press V, which has been preheated in the usual way, and heat and pressure are allowed to act on the charge in accordance with the time and temperature range prescribed for the rubber composition of the layers. Typically, this range is about 14-9 to 155 ⁰ O (300 to 312 ⁰ F) for 8 to 12 minutes. In general, the hardening of the rubber compound begins after about 3 minutes in the press and is finished after about 8 minutes.The flow within the rubber compound of layers 11 and 30 causes the formation of the thicker sections 19 in layer 12 under the finished shaped elements 14, while the thinner sections 20 are formed where the die supports the layer 11 in the areas that will become dead areas of the finished laminate.

example 1

Some laminates were made with a nominal total final thickness of 0.318 cm (0.125 inch). The cushion layer 12

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was prepared by calendering p, p'-oxybis (benzenesulfonyl) hydrazides in the form of discrete particles as a foaming agent in a layer based on an uncured Natural rubber mass until the particles were completely distributed within the layer and they made up about 3% by volume the shift. Such a foaming agent is commercially available from Uniroyal under the name "Celogen OT" The calendered thickness of the sheet was nominally 0.0635 cm (0.025 inch).

Thereafter, one load (filling) was made for each laminate Made for a conventional compression molding press by applying a layer of a simple (pure), uncured Natural rubber compound with a nominal thickness of 0.102 cm (0.040 inch) on the matrix and then applying a Layer from the uncured rubber compound with the foaming agent on the layer from the simple rubber compound. Then became on the layer of the rubber compound with the foaming agent a backing layer (backing layer) made of a simple, uncured one Natural rubber compound, nominally 0.152 cm (0.060 inch) thick, applied to complete the load with a nominal overall thickness of 0.318 cm (0.125 inch).

Each charge was placed in the compression molding press and it was cured using heat and pressure for the period customary for the gum composition. The pressure was 163j5 tonnes (180 tons), the temperature was about 152.5 ⁰ C (307 ⁰ F) and the duration was about 10 minutes for each resin composition · After curing has been removed, the laminate and mounted on a common Einspannprüfmaschine. Because tone and process printing is the most difficult to achieve, six-color printing type laminates were made comprising a total of 5 ^ laminates.

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Representative impression tests were carried out and it was found that a satisfactory print could be obtained immediately after the initial contact point was reached between the printing surface of the printing elements and the printing cylinder. The distance between the plate cylinder and the impression cylinder was' reduced until the interference was about 0.279 cm (0.011 inch) with no undesirable dot growth (this test is used in the printing industry used to determine the point at which the print destroys the imprint) · The point growth is so far in usually occurred with conventional printing plates for color tone and process printing when the interference exceeds the value by about 0.00076 cm (0.0005 inches).

The finished laminates were taken off the fixture tester taken out and using the usual double-sided adhesive, usually as "adhesive backing (adhesive pad)" labeled, mounted on commercially available anil printing presses with the laminate attached to the printing cylinder. The laminates together were enough to produce a multicolored print with halftones ·.

The first advantage over the previously known printing plates that was found was that the time required to set the prints and to align all of the laminates 2J? to JO minutes compared to 3 to 7 hours for the previously known printing plates. This is due to the ability of the laminate to compensate for a slight misalignment between the surface of the printing cylinder and the impression cylinder, as well as between the printing cylinder and the anilox roller, so that the laminate is colored evenly and a good impression is guaranteed over a much wider tolerance range than with the previously known printing plates

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Compensate tolerance range

Another advantage over the previously "known printing plates" was observed during the printing process · It occurred when the double thickness of a "flying splice" on the substrate to be printed passed the printing press Imprint settings between the different stations did not change when the "splice" passed the printing press, while with the previously known printing plates, these adjustment and impression settings have been changed. By the elasticity of the laminates according to the invention could do this Change can be prevented · Also, a break in the substrate during the printing process only led to a small change the adjustment, whereby a quick compartment adjustment was possible after the repair of the fracture · The impression settings were not changed · When using the previously known printing plates, such a break often resulted in the Adjustment and impression settings were shifted so much that it took a considerable amount of time to adjust the Adjusting the printing press again and setting the imprints again

Example 2

A set of laminates were made which should have a nominal total final thickness of 0.318 cm (0.125 inch). The cushioning layer 12 was made by calendering p-, p ^l -oxybis (benzenesulfonyl) hydrazide in the form of discrete particles as a foaming agent uncured layer based on a natural rubber compound until the particles were evenly distributed within the layer and made up about 3% by volume of the layer. The calendered thickness of the layer was nominally 0.0635 cm (0.025 inch). Then the layer became flat between two Matrices were placed in a conventional compression molding press and the cover strips or side irons were so

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set that a layer about 0.0889 cm thick The press was placed over the sheet after preheating to a pressure of about 17.6 kg / cm (250 psi) closed and the layer was heated to about 152.5 ° C (307 ° F) for 8 minutes. This caused that the layer was foamed and hardened by the gasification of the foaming agent · The foamed layer became then removed and measured. The cured cushion layer had a nominal thickness of 0.0914 cm (0.056 inch). Die cured cushion layer also had a thin surface skin so that none of the pores (voids) opposite the surface the shift was open. The layer was compressible to about 3/10 of its normal thickness and then returned relax to their normal thickness.

The finishing touch for each laminate was then made by applying a layer of simple, uncured natural rubber compound nominally about 0.1016 cm (0.040 inch) thick to the type of die, then applying the cured cushioning layer to the rubber layer cured cushioning layer a backing layer of simple, uncured natural rubber compound is applied to a nominal thickness of 0.1524 x cm (0.060 inch) to complete the load. Each batch was placed in the compression molding press and cured using the usual heat, pressure and time for rubber compounds ⁰ F) and the time was about 10 minutes. After removing the finished laminate, it was found that the top layer was firmly vulcanized onto both the surface layer and the backing layer and that thicker sections were present in the pad layer under the printing elements, while under the non-printing areas of the surface layer thinner

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Sections were in place.

The invention has been described above with reference to
preferred embodiments explained in more detail, but it is clear to the person skilled in the art that it is by no means restricted thereto, but that these can be changed and modified in many ways without thereby departing from the scope of the
the present invention is abandoned

Patent claims:

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Claims (1)

Claims Printing plate laminate, characterized in that it consists of a printing plate made of a hardened rubber compound and a pad of the same size as the pressure plate, which has a layer of a hardened rubber compound with evenly Contains cavities distributed therein, the cushion simultaneously with the hardening of the printing plate on the printing plate has been vulcanized and the cavities through a uniformly dispersed in this layer before hardening Foaming agents have been formed and wherein the foaming agent has been selected to be the layer foams within the curing temperature of the layer. ■ 2 * printing plate laminate according to claim 1, characterized in that that the foaming agent contained therein is selected so that the foaming is within the curing temperature range occurs before the layer has substantially hardened, 3. Printing plate laminate according to claim 2, characterized in that the printing plate and the layer of the rubber compound of the cushion cure within the same temperature range and that the printing plate and the layer cured at the same time have been. 4-, printing plate laminate according to claim 3, characterized in that that the pressure plate has raised pressure elements and lower-lying pressure areas and that the cushion is thicker under the printing elements than under the Hicht-Druck districts. -. 5. Printing plate laminate according to Claim 4, characterized in that that the cushion under the pressure elements is a prescribed distance from the pressure surface of each pressure element, 4Ö9840 / 0827 which is so large that a considerable proportion of the "at The deformation of the pressure element that occurs during bridges is transferred to the padding underneath 6 · 'Printing plate laminate according to claim 5 »characterized in that that there is a material from the group of the azo compounds, the N-nitroso compounds, as a foaming agent. the Contains sulfonyl hydrazides and inorganic carbonates 7. A method for the production of a flexible, padded pressure laminate in a compression molding press, characterized in that, that he (a) a first layer of a vulcanizable rubber compound with a foaming agent dispersed therein on a second layer of a simple (pure) vulcanizable Rubber mass puts on for the production of a charge and (b) Allowing heat and pressure to act in the compression molding machine to Foaming agent in the first layer and both the first and second layers at the same time to cure and vulcanize these layers together to form a uniform laminate. 8 · The method according to claim 7 »characterized in that in step (a) a third layer of simple vulcanizable compound is used to prepare the charge is placed on the side of the first layer facing away from the second layer, so that the third layer simultaneously with the first and second layers are hardened in step (b), 9 · The method according to claim 7 »characterized in that step (a) by calendering the first and the second shift is carried out. 409840/0827 10 · The method according to claim 7 »characterized in that that before carrying out step (a) for the production of the first layer a SCHÄuiamittel evenly in one Rubber mass is dispersed. 409840/0827