EP2454413B1 - Device for applying color effekt pigments - Google Patents

Description

TECHNICAL AREA

The present invention relates to a device, in particular for the application of color effect pigments, such as, for example, iridescent pigments, to processes for applying, in particular, such pigments to such a device and to print substrates produced with the aid of such processes.

STATE OF THE ART

Among other things from the EP 490825 It is known that it is possible to apply iridescent pigments in the form of strips to a substrate, for example a paper for banknotes, which strips may have different colors of the pigments. Such strips are used, for example, in security documents such as banknotes, passports, identification cards, visa labels, tickets, postage stamps, tax stamps, certificates, birth certificates, vehicle identity cards, bill of lading, guarantee certificates, labels and similar documents, since the color-changing effect of these strips is due to modern reproduction methods, for example Color copiers, color scanners, color printers, digital cameras and similar methods can be adjusted only insufficiently.

For the application of these strips, a device is proposed on the one hand, in which the corresponding pigmented ink is first applied to a roll of application with the aid of individual pipette-like devices on the roll and then on the role, which rests on the substrate web and runs along with this on the substrate web is applied.

Alternatively, it is proposed, also with such a role, the individual colors in individual areas which are separated with walls, applied to the substrate. Problematic in connection with such application of color effect pigments e.g. With iridescent pigments it is, inter alia, that the number of individual stripes arranged in the immediate vicinity of each other, i. directly adjacent to each other or by distances from each other spaced individual strips, is limited in the proposed construction to a few and the width, also due to design, a certain level can not fall below. As a result, the number of individual strips arranged in direct proximity to one another is limited.

Another problem is in connection with such a plot of color effect pigments eg with iridescent pigments, inter alia, that the application process in terms of order quantity, strip width, etc., can be insufficiently controlled, what Among other things, in terms of the often temperature-dependent viscosity of the colors for the process stability is problematic. This is particularly the case when a plurality of strips and / or strips of small width to be applied. From the FR2429292 is a security paper known with a serving as a security feature order of an iridescent pigment. Different methods are given as application methods, in particular printing processes (heliogravure) or rod application (Meyerbar). Other application methods are not specified.

PRESENTATION OF THE INVENTION

It is inter alia an object of the invention to propose an improved apparatus for the application of a paint to a substrate, in particular in connection with the application of color effect pigments, e.g. iridescent pigments, on substrates for example for the production of security documents. Color effect pigments are pigments whose optical effect comes about through normal reflection or interference. The color changes in such pigments depending on the viewing angle and / or as a function of the angle of the incident light. The pigments used for this purpose are typically optically anisotropic particles which, when applied as a color layer, are anisotropically distributed in a support or a matrix in space. The application process should proceed in such a way that the pigments in the color layer are not distributed isotropically in their spatial orientation at the end, since otherwise the color change effect does not occur or occurs only to a small extent.

It is a further object of the invention to propose a device for applying a paint to a substrate, which allows to apply a plurality of fine (ie small width), in direct proximity to each other arranged single lines in different colors. An essential advantage of this device, in contrast to the devices known in the prior art, is that it opens up the possibility of creating a multiplicity of color combinations, which form a color code, which are used for the identification of documents, by the multiplicity of single strokes in different colors can.

The invention relates, inter alia, to a device for applying a color to a substrate web guided past the device along a running direction. The device is according to the invention, characterized in that it has a preferably convexly formed in the direction and perpendicular to the direction of trained surface area, which can be brought into contact with the substrate web, and that in the convex surface area one, preferably at least two separately controllable with color, offset in a direction perpendicular to the direction of passage openings are provided for the color by which the ink is applied directly to the substrate web. In this case, due to the convex surface of the device, the application amount of the color depends on the angle of attack of the device with respect to the substrate. Specifically, the application amount is dependent on the smallest height of the gap substantially at the contact line between paper web and coating head contour or behind, and the coating head contour at this somewhat lowest point can with the angle between the plane of the substrate web and the normal to a tangent plane at the surface area at the Position of the respective passage opening can be varied.

Instead of a convex formation in the surface area, a flat plane is also conceivable, e.g. using a square head, Also possible are stepped areas.

It should also be mentioned that the order quantity is also influenced by other parameters, such as: from the viscosity of the coating color, the hydrostatic pressure, which relies on the application of the coating color at the place of application, the web speed, the contact pressure of the device on the substrate web, the depth of the depressions (see below), etc. Since these parameters are can change over time, for example, the viscosity of the color can change depending on the ambient temperature, the inventive device provides an extremely comfortable solution to compensate for such difficult to control changes by adjusting the angle of attack in a simple manner. Known devices and methods do not allow a similarly simple correction.

A fixture for such devices, which allows for a corresponding adjustment of the angle of attack, is quite generally preferably constructed so that the device can be rotated therein about its central axis (ie for adjusting the angle of attack about an axis perpendicular to the conveying direction of the substrate web), and preferably can also be moved transversely to the direction of travel over the substrate web (for example, to determine different transverse positions or even for the generation of wavy lines as a function of time variable), and perpendicular to the Paper web can be lowered. By the vertical lowering it is possible to press the device onto the substrate web, which is underlaid from its underside with a counter-pressure element. The pressing force with which the device is pressed onto substrate web and counterpressure element is, for example, in the range from 0 to 300 N, more preferably in the range from 20 to 150 N, in particular preferably in the range from 50 to 70 N.

In particular, if, as preferred, the passage opening is a circular bore, results in a curved contour in the space of the passage opening due to the convex plane through which passes through the passage opening. As a result of this convex curvature, inter alia, the dependence of the color applied on the substrate by this opening arises from the angle of attack of the device with respect to the substrate web. Such an angle of attack can easily be realized with such a device (corresponding suspension of the entire device or at least its convex surface, in which the angle of attack can be set either manually or automatically), and the angle of attack allows a targeted control of the order quantity of the applied color.

A first preferred embodiment is characterized in that in the region of at least one, preferably each passage opening in the surface area a recess is arranged, which widens the passage opening in the running direction with a depth. The depth of such a depression is typically in the range of at most 3 mm, for example in the range of 0.05-2 mm, preferably in the range of 0.1-1 mm, particularly preferably in the range of 0.1-0.5 mm. The depression is either substantially equal in width (transverse to the direction of travel) to the diameter of the passage opening, but it may also, and is preferred for certain applications, be larger than the diameter of the passage opening measured in a direction perpendicular to the direction of travel. In principle, namely, the passage opening may be circular, but it may also be oval, wherein preferably the long main axis is arranged perpendicular to the direction and the short main axis parallel to the direction.

According to a further preferred embodiment, the depression is designed to run out in the direction of travel, preferably over the entire width of the depression. The recess can also be closed at least partially in the direction of travel to the rear, so it may be formed, for example in the form of a pot-like milling. In principle, such a depression can be produced by inserting a corresponding milling tool into the material of the convex surface in the region of the passage opening to the desired depth at this point and then guided backwards out of the device to form the depression. If the milling tool is guided completely backwards out of the device, the linear outlet edge described above is formed at the location where the milling tool leaves the workpiece, which recess is designed to extend over the entire width. If the milling tool previously led out of the material, the said pot-like depression is formed.

The webs between the recesses of adjacent passage openings may extend to the exit edge of the recesses, but they may also end previously, so that connect in the region of the trailing edge, the recesses of adjacent passage openings together. The webs may extend in the form of webs of constant width parallel to the transport direction of the substrate web. However, they can also be designed to converge towards the rear (successively decreasing width, possibly even to a point in front of the trailing edge). In addition to reducing the height of the trailing edge above the substrate web and thus the amount of application is then accompanied by a change in the angle of attack and a change in the outlet width.

A further preferred embodiment is characterized in that the device is formed, at least in the surface area, as part of a circular cylinder, through the cylinder surface of which the passage openings pass. The radius of such a cylinder surface is in the range of 3 to 50 mm, more preferably in the range of 3 to 15 mm, particularly preferably in the range of 4 to 10 mm. Preferably, the device comprises an entire circular cylinder. Particularly when using an entire circular cylinder, radii in the range of 3 to 15 millimeters, in particular preferably in the range of 4 to 10 millimeters, are preferably used. This circular cylinder can then be formed as a solid, preferably made of metal (for example steel, copper, brass) circular cylinder whose axis is arranged parallel to the plane of the substrate web and perpendicular to the direction in which the passage openings are formed as central through-holes. Since the temperature can typically increase during application due to the friction between the device and the substrate web, it may be advantageous to in the circular cylinder means for temperature control of the same, for example in the form of channels for a corresponding liquid or a gaseous medium for temperature control.

A further preferred embodiment is characterized in that blind cut-outs-that is to say non-ink-carrying depressions-are arranged laterally of the passage openings. Typically, the passage openings are preferably arranged in a line next to one another. In particularly fine areas, it may also be advantageous to offset the passage openings alternately in the running direction against each other to create enough space for the ink supply.

Preferably, a counterpressure body is arranged on the side of the substrate opposite the device, which is designed to be flexible in order to ensure homogeneous contact pressure across the width of the device. By means of this counter-pressure element, further possible tolerances of the substrate thickness occurring in the case of paper, in particular in the region of watermarks, can be compensated. In particular, if such a soft counter-pressure body is used, it may happen that the substrate bulges into the device to some extent, where it comes into contact with the device. This can lead to the paint application being greater in the laterally arranged regions than in the central regions, because there the curvature presses the substrate less strongly into the device than in the centrally arranged regions. This effect can be significantly reduced by the mentioned blind milling.

As a counter-pressure body, a follower structure (roller) or a stationary structure, on which the substrate web slides, may be provided. The surface of this body can be made of a soft resilient material, such as plastic or felt, a brush structure is possible. In the case of felt as a stationary counter-pressure body, for example, a felt with a bulk density (according to DIN 53855) in the range of 0.15-0.6 kg / dm3, preferably in the range of 0.2-0.4 kg / dm3, proves to be suitable.

It is also possible to equip the device with a plurality of areas, which are color-leading connected depending on the application or receive no color guide. For example, a device with 10 areas for applying single strokes can be used to apply any number between 1 to 10 individual strokes, depending on which areas are supplied with color. Furthermore, it may happen that the edge definition of the outermost regions, which do not adjoin another neighboring color region on their outer boundary line, do not have the same edge definition as two adjacent regions. In this case, it may prove useful to provide laterally each a further area that applies a non-pigmented and therefore colorless formulation as a line. Thus, it can be ensured that all colored areas have a comparable edge sharpness.

In addition, it is generally possible to apply formulations which are also colorless in daylight but have hidden properties, for example fluorescence in the ultraviolet light due to the addition of fluorescent dyes or revealed by the admixture of liquid-crystalline pigments when viewed through a polarizing filter. It is also possible to incorporate pigments having polarized absorption and / or emission properties, analogous to that described in US Pat PCT / CH2005 / 000380 respectively. EP05754354.8 mentioned subject invention.

A further preferred embodiment is characterized in that in the region of at least one, but preferably each passage opening in the surface area a recess is arranged, which expands the passage opening in the running direction with a depth that the recess is formed in the running direction expiring, and that the recesses of adjacent passage openings not separated by a web at least in the region of a common exit edge. In other words, the recesses connect either at the trailing edge or even before it. Surprisingly, this results in no significant mixing of the individual coating colors, although these are not separated by a bridge over a certain distance. On the contrary, in this preferred embodiment directly adjacent to each other areas with very high edge sharpness.

However, it is possible, if desired, under certain circumstances, a targeted intermingling of the colors in the area to effect. The corresponding mixed colors can be used for example for the production of rainbow-like structures. This can be provoked, for example, in that the adjacent areas are pressed together before leaving the coating head. A corresponding embodiment will be given below. This is possible, for example, when the angle of attack or the contour in the contact area of the coating head is selected so that the color is not exclusively back out of the Spreading head exits to the substrate, but in a sense partially protruding forward (against the direction), before the coating head an accumulation or stagnation forms, where in adjacent areas color areas can merge into each other, and only after this process on the substrate then in the edge areas Into each other overflowing color is transported under the coating past. Such a situation is preferred in particular when the recess is not directed backward but forward, which corresponds to a further preferred embodiment. In general, a cellulose-based substrate such as paper is preferably used as the substrate. Preference is given to a security paper which in turn may already have security features such as watermarks, mottled fibers, etc. Such a substrate can subsequently be made into a security print carrier and, for example, further processed into a banknote or a security document.

Of course, other substrates, such as films, composite films, as well as other printing substrates, in particular security printing substrates, come as a carrier in question. In a preferred embodiment, substrates are used which are at least partially transparent (windows), and coatings are preferably applied with the device according to the invention in these transparent areas. When pigments are used which have different absorption and transmission characteristics, interesting effects arise on such transparent substrates, such as, for example, color inversion when viewing is changed from top view to review.

Preferred such a device is in connection with a color with color effect pigments, ie color change, or effect pigments, so-called color-shifting or color-shifting pigments or optically variable pigments in particular iridescent or so-called pearlescent pigments application. An overview of such pigments are, for example, Optical Security and Counterfeit Deterrence Techniques IV, SPIE 4677, 2002 and the references cited therein. Such pigments have angle-dependent reflection properties and therefore exhibit different reflection colors at different viewing angles. Examples of such pigments are Iriodin® from Merck GmbH, Phoenix from Eckart, Xymara and Metasheen from Ciba, Firemist from BASF, SunGEM from Sun Chemical, QolorTech Pearl from QolorTech, Helicone from Wacker, Special Diamond from SpecialChem, Taizhu Pearl Pigments from Wenzhou Pearlescent Pigments Co. LTD, as well as ChromaFlair, SpectraFlair, and other Flex Products, Inc. products, just to name a few.

In order to be applied with such a device, this color preferably has a viscosity in the range of 20-70 mPas, preferably in the range of 35-60 mPas, particularly preferably in the range of 40-55 mPas.

The colors are preferably supplied to the device from a first storage vessel, which in turn is fed via a second storage vessel, for example via peristaltic pumps, and wherein the first storage vessel has an overflow which returns the overflowing paint to the second storage vessel. The feeding is preferably carried out in abundance, so that the level of color in the first storage vessel and thus the hydrostatic pressure of the color, by the height difference of the first storage vessel and device, remains almost constant.

A further preferred embodiment of such a device is characterized in that it additionally has a compressed-air nozzle, which to a certain extent is arranged on the rear side of the device and which is directed onto the freshly applied color strip. The compressed air nozzle and the compressed air jet emerging therefrom displace the freshly applied paint and can be used to separate a single applied strip into two separate strips. Such a nozzle may be periodically pivoted as a function of time in a direction perpendicular to the direction of travel (eg via an eccentric motor) so that the substrate area exposed by the compressed air takes the form of a wavy line. Thus, it is possible to produce strips which are just delimited at the edge and which have in the middle a wavy strip in which the substrate is exposed. Of course, it is also possible to move the entire device periodically as a function of time in a direction perpendicular to the direction and to let the strip as a whole wave-shaped. This, in combination with such a compressed air nozzle, may give rise to exceptional safety features, such as wavy lines, which have wavy stripes in the middle in which the substrate is exposed. These wavy strips, in which the substrate is exposed, may be formed in phase, in opposite phase at the same frequency as that of the overall strip, or else at a different frequency than that of the overall strips, so that astonishing optical effects are possible. Further, it is possible to make the amplitude of the air nozzle wider than the stripe width set, whereby the strip is completely interrupted zone by zone.

The device allows the very targeted generation of stripes of different colors next to each other with a highly defined distance. This distance can deliberately be set very low, in other words, between two strips a strip in which the substrate is exposed can be produced, which has a very narrow width. Such so-called "speed cameras", since they can not be reliably generated in a conventional sequential printing process, can be selectively generated as a very efficient security feature. The distances in such a case are, for example, in the range of 0.1-0.5 mm, which is below the usual register accuracy of conventional printing methods. With such fine distances, an exceptionally strong color contrast can be achieved between the individual strips, since the individual strips are completely separated from one another, but because of their fineness the distances are visually barely discernible.

In addition, it is possible to equip such a device with a periodically actuated valve for the supply of the printing ink. The selective opening and closing of this valve can be used to create dotted lines to create dashed lines, which in turn in combination with a lateral displacement of the entire device, possibly even in combination with a compressed air nozzle, interesting additional visual effects, especially at the use of color effect pigments eg with iridescent pigments, possible.

In addition, the device allows the production of exceptionally narrow strips with high precision. For example, strips of a width in the range of 0.5 mm to 0.4 cm can be produced, which is not possible in the methods according to the above-mentioned European specification. In conventional doctoring process so small line widths can not be achieved because z.T. the stroke width is of the order of magnitude of the squeegee windings customary for such colors.

Furthermore, the present invention relates to a method for producing at least two juxtaposed, preferably spaced-apart strips, preferably of different color, or dotted lines on a substrate using a device as described above. The method is preferably characterized in that the substrate is preferably passed in the form of a web, along a running direction on the device and in contact therewith, either continuously (strip) or intermittently (Dotted or dashed lines) color is applied through the device directly through the openings on the substrate (without additional use of a roller) and then dried.

According to a first preferred embodiment, such a method is characterized in that a soft counter-pressure element is arranged on the side of the substrate facing away from the device, the purpose of which has already been explained above.

Furthermore, such a method may preferably be characterized as already explained above, that in the running direction on the rear side of the device, a compressed air nozzle is arranged, which in periodically deflected perpendicular to the direction of the fresh strip directed a compressed air jet, so that a wavy spacing between the strips results in which the substrate is exposed.

Furthermore, the present invention relates to a substrate, particularly preferably security paper, produced with at least two strips or dotted lines with the aid of a method as explained above.

Such a substrate may for example be characterized in that the strips have a width of at least 0.05 cm and at most 0.5 cm, preferably at most 0.25 cm, and have a non-zero distance, typically of at most 0.5mm, preferably the distance is in the range from 0.1-0.5 mm. Especially with spaced strips, a tactile, tactile effect can result. This is the stronger, the higher the application weight of the individual strips, and it can be additionally reinforced, in which the color, for example, self-expanding pigments are buried.

A further preferred embodiment of such a substrate is characterized in that the strips or line-shaped points are wave-shaped with periodic deflections perpendicular to the running direction.

The strips are preferably of a color having color effect pigments, e.g. with iridescent pigments formed, whereby mixtures of different such pigments can be used.

The strips may also be formed from colors which contain, in addition to or in place of the effect pigments, normal, absorbing pigments and / or dyes. In a preferred embodiment, a single strip with an effect pigment executed, a further, preferably adjacent individual strips running with a normal pigment or dye without color change effect, wherein the two strips in a view from a first viewing angle have an identical hue and thus appear as a single, homogeneous application of paint, when viewed from a second angle, however the color of the color change pigment changes and the strip becomes recognizable as a combination of two different individual strips. Also, preferably, adjacent, individual strips can be realized with metameric colors which appear identical under one light source but differ under another light source.

Further, the colors may contain substances that impart additional properties to the respective strip, such as electrical conductivity, magnetic properties, infrared absorption, fluorescence, phosphorescence, photochromism, and so on.

Furthermore, the present invention relates to the use of such a substrate as a security document, in particular banknote, access card, ticket, security. Other applications are not excluded.

Further embodiments are given in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1

eine perspektivische Ansicht auf eine Streichvorrichtung für die Erzeugung von drei Streifen;

Fig. 2

in a) eine Ansicht von unten auf einen Streichkopf ohne Vertiefungen und in b) einen Schnitt entlang der Linie A-A in a) sich eine solche Vorrichtung;

Fig. 3

in a) eine Ansicht von unten auf einen Streichkopf mit Vertiefungen mit planem Boden und gerader hinterer Auslaufkante und in b) einen Schnitt entlang der Linie A-A in a) sich eine solche Vorrichtung;

Fig. 4

in a) eine Ansicht von unten auf einen Streichkopf mit Vertiefungen mit planem Boden und gekrümmter hinterer Auslaufkante und in b) einen Schnitt entlang der Linie A-A in a) sich eine solche Vorrichtung;

Fig. 5

eine Ansicht von unten auf einen Streichkopf mit Vertiefungen und seitlichen Blindfräsungen;

Fig. 6

in a) eine Ansicht von unten auf einen Streichkopf mit Vertiefungen mit planem Boden und gerader hinterer Auslaufkante, wobei die unterschiedlichen Anstellwinkel, wie sie in b) in seitlichen Ansichten dargestellt sind, mit Kontaktlinien zum Substrat angegeben sind;

Fig. 7

in a) eine Ansicht von unten auf einen Streichkopf mit Vertiefungen mit planem Boden und gekrümmter hinterer Auslaufkante, wobei die unterschiedlichen Anstellwinkel, wie sie in b) in seitlichen Ansichten dargestellt sind, mit Kontaktlinien zum Substrat angegeben sind;

Fig. 8

eine Ansicht von unten auf einen Streichkopf nach einem weiteren Ausführungsbeispiel mit Vertiefungen mit planem Boden, Vorrats-Vertiefung und hinterer Auslaufkante und seitlichen Blindfräsungen;

Fig. 9

eine Ansicht von unten auf einen Streichkopf mit Vertiefungen mit planem Boden und hinterer Auslaufkante mit Bemassungen; und

Fig. 10

in a) eine Ansicht von unten auf einen Streichkopf mit nach vorne gerichteten Vertiefungen mit planem Boden zur Erzeugung von fliessenden Übergängen zwischen den Farbstreifen, wobei in b) eine seitliche Ansicht angegeben ist.

Preferred embodiments of the invention will be described below with reference to the drawings, which are given by way of illustration only and are not to be interpreted as limiting. In the drawings show:

Fig. 1

a perspective view of a coating device for the production of three stripes;

Fig. 2

in a) a view from below of a coating head without recesses and in b) a section along the line AA in a) such a device;

Fig. 3

in a) a view from below of a brush with recesses with a flat bottom and a straight rear edge and in b) a section along the line AA in a) such a device;

Fig. 4

in a) a view from below of a brush with recesses with a flat bottom and a curved rear edge and in b) a section along the line AA in a) such a device;

Fig. 5

a view from below of a coating head with recesses and side Blindfräsungen;

Fig. 6

in a) a view from below of a brush head with recesses with a flat bottom and a straight rear edge, wherein the different angle of attack, as shown in b) in lateral views, are indicated with contact lines to the substrate;

Fig. 7

in a) a view from below of a brush with recesses with a flat bottom and a curved rear edge, wherein the different angles of attack, as shown in b) in lateral views, are indicated with contact lines to the substrate;

Fig. 8

a bottom view of a coating head according to another embodiment with recesses with a flat bottom, storage recess and rear outlet edge and side Blindfräsungen;

Fig. 9

a bottom view of a coating head with recesses with a flat bottom and rear outlet edge with dimensions; and

Fig. 10

in a) a view from below of a brush head with flat bottomed forward depressions for creating smooth transitions between the color strips, wherein a side view is given in b).

DESCRIPTION OF PREFERRED EMBODIMENTS

In FIG. 1 is a perspective view of a coating head 1 shown, under which a substrate web 3 along a substrate running direction 12 is moved. On the front side 18 of the coating head 1 are still no stripes of an iridescent color (or generally a color with color effect pigments) on the substrate web, the strips are generated in the contact area between the coating head 1 and substrate web 3 (detailed discussion below) and are on the rear side 19 can be seen applied to the substrate. The strips 4 are in this case of the same width, there are three such strips 4 and between the strips 4 there is a respective distance 5.

The coating head 1 is in the form of a solid cylinder, for example, formed of a metal, and for each strip 4 there is a separate supply line 2. The coating head 1 is thus formed as a solid circular cylinder and has a circumferentially convex peripheral surface 20th

On the side facing away from the coating head 1 back of the substrate 3 is a Counter-pressure element 29 arranged (see also FIG. 2b ). This counterpressure element 29 together with the coating head 1 clamps the substrate web 3 to some extent and is preferably made of a soft material, ie, for example, by a flexible plastic surface or by a felt backing having a bulk density (a measure of the hardness of felts, DIN 53855). Preferably in the range of 0.15-0.6 kg / dm3, in particular preferably in the range of 0.2-0.4 kg / dm3 formed. Thus, an optimal contact pressure of the substrate web 3 on the application area of the coating head 1 is ensured in order to ensure a homogeneous as possible strip formation (same thickness across the width of the strip and independence of the same of irregularities in the paper).

The counter-pressure element 29 may alternatively consist of rubber, sponge rubber, or foam and may be constructed in one or more layers. Thus, for example, a counter-pressure element made of soft foam may additionally have a felt support, wherein the felt support comes into contact with the substrate web. This preferred embodiment is characterized in that the counter-pressure element adapts very well self-regulating the paper web by the soft foam, but at the same time a felt with the right hardness and good sliding properties is in contact with the paper web.

A similar self-regulating storage can also be realized by a flat brush or a construction with compression springs. The counter-pressure element can be upright, but it can also be a follower roller.

In order to prevent scratch marks in the substrate web from arising at the edges of the device, this may be angled or rounded at the edges.

A coating head 1 in a first construction, a particularly simple construction, is in FIG. 2 shown, in FIG. 2a a view from below, that is to say to some extent from the perspective of the substrate web 3 is shown and in b a section along the line AA, as shown in FIG. 2a is shown. In this case, the coating head has means 6 for generating three strips 4, but it could also be more such openings 6 are provided for the formation of stripes or less, for example, only such an outlet channel 6 for color.

The coating head 1 is made here as a solid circular cylinder of a metal such as brass or stainless steel and has a series of three through the center extending through holes, each of the substrate 3 facing the end Form openings 6, through which the paint exits onto the substrate 3. On the side facing away from the substrate 3, this hole has a slight extension so that a gradation 25 is formed. In this step, a feed line, preferably a metal tube 26 is inserted, this, as in FIG. 2b shown, for example, so that the inner diameter of this tube 26 corresponds to the inner diameter of the lower portion of the through hole. The bore 21 thus has a radius greater than the wall thickness of the tube 26 than the bore in the lower region.

As in particular by means of FIG. 2b can be recognized, resulting due to the cylindrical formation of the bore and the curved surface 20 of the cylinder an opening which, although in the projection according to FIG. 2a is circular, but which is curved in space. Correspondingly, this opening 6 has a circulation line 22 arranged on the surface 20, which to a certain extent has a front zenith 23 toward the front side 18, and a rear zenith 24 on the side facing the rear side FIG. 2b is arranged in a position so that the axis of the bore 6 is oriented perpendicular to the plane of the substrate web 3, then the front zenith 23 is slightly above the substrate web and also the rear zenith 24 is at the same height slightly above the substrate web, and the contact between the coating head and the substrate web 3 takes place to a certain extent with respect to the two zeniths 23 and 24 offset by 90 degrees on a line which in FIG. 2a at the right-lying hole 6 is indicated by dashed lines. In particular, by the horizontal distance between this rear zenith 24 and the substrate web 3, ink exiting down through the channel and through the bore 6 exits the substrate web and forms a strip substantially the width of the bore 6. As discussed below To be described in more detail, the application thickness can be adjusted very controlled by the inclination angle of the coating head.

In FIG. 2a the two diameters are shown either perpendicular to the direction D _s or parallel to the direction D _p . In this embodiment, it is a circular opening, ie D _P is the same size as D _S. But it is also possible to design the opening oval, for example so that D _{S is} greater than D _P. Due to the design of the opening cross-section, among other things, the color thickness along a direction perpendicular to the substrate running direction 12 can be adjusted and optimized.

In FIG. 3 a further embodiment of a coating head is shown. In this Case there is next to the through holes 6 on the substrate web 3 facing side of the coating head 1 in the convex portion 28 thereof an additional recess resp. Recess 7. This depression is formed in the form of a channel extending to the rear side 19 with the same extent perpendicular to the running direction 12, and this channel, with a flat bottom surface, runs rearwards to the rear side 19 so that a transversely to the substrate running direction 12th arranged rear trailing edge 27 forms.

By such a design, as will be described below with further figures, the exit characteristic of the color can be further improved and, in particular, it is possible to adjust the color thickness over the inclination angle of the coating head over a larger inclination angle range than in the embodiment according to FIG FIG. 2 to adjust reliably.

In FIG. 4 a third embodiment of such a coating head is shown. In the embodiment according to FIG. 3 is used to produce the recess 27 normally a cutter, which has a same diameter as the bore 6, this cutter is for example introduced coaxially with the bore 6 in this and then drove out to some extent to the rear side 19 of the device 1 out of the cylinder of the device , wherein the recess 7 is formed as a rearwardly open channel. In the embodiment according to FIG. 4 Now a milling cutter with a larger dimensioning is used to manufacture the recess 7, ie with a larger diameter than the diameter of the bore 6. This larger cutter is also fed to the bore 6, but not coaxial with this but so that the outer contour of the Milling cutter at the foremost point on the front zenith 23 comes and led in accordance with the desired depth into the cylinder. Subsequently, the cutter is moved to the rear side 19, but not as in the embodiment according to FIG. 3 pushed out completely but already moved out of the cylinder again in a direction parallel to the axis of the milling cutter. This then results in a situation in which, as it were, an edge remains to the rear side 19 and not just a linear open rear trailing edge 27 as in FIG. 3 results. In the embodiment according to FIG. 4 In this case, the cutter has just been led back so far that at the rearmost point, which in FIG. 4 is indicated by the reference numeral 30, the bottom of the recess 7 just merges into the surface 20. It is also possible, the cutter move slightly less far to the rear, then, as it were, results in the rear towards a slightly closed recess which is somewhat pot-shaped. When changing the angle of attack in this embodiment (see also FIG. 7 ), the points of contact with the paper migrate from along the edges of the contour toward the zenith 30 and thus to some extent close the application from the side with decreasing angle of attack. The embodiment is correspondingly more "tolerant" in terms of adjusting the angle of attack, for example, an embodiment according to the Figures 5 or 6 where only the channel in height is closed successively when hiring, when the angle of attack is reduced.

Another possible embodiment is in FIG. 5 it is essentially analogous to that according to FIG FIG. 4 However, the cutter is led out completely back out of the cylinder so that a linear trailing edge results as in FIG. 3 , As a result of the counter-pressure surface 29, which is preferably soft in design, it is possible for the substrate web as a whole in the region of the row of openings 6 to bulge to a certain degree towards the coating head 1. This can then lead to the outer strips, where the curvature is not yet pronounced, have a greater inking thickness than at the central openings, since there the curvature is strongest and to some extent the substrate web is pressed the furthest into the coating head.

In order to largely avoid this effect, it is possible, on one side or preferably on both sides of the actual outlet openings on the coating head 1, to form lateral blind milling cuts 16. These blind cuts are preferably configured with the same depth and in shape as the depressions 7 and lead to a deformation of the substrate web in the coating head, if any, is not different for the individual juxtaposed outlet openings. 6

Based on FIG. 6 Now, for a further embodiment of a coating head, in which a milling cutter as in the embodiment according to FIG. 4 is used is completely led out to the rear of the coating head and correspondingly a trailing edge 27 results, as in connection with FIG. 3 was described (analog FIG. 5 ), how a differently adjusted angle of inclination of the central axis 31 of the bore 6 to the plane of the substrate web 3 gives rise to a different thickness of the paint application.

In the sectional view according to FIG. 6b on the left side (situation A) is shown what happens when the axis 31 is oriented perpendicularly (angle of attack equal to 90 °) to the plane of the substrate web 3. In this case, the supplied through the supply line 2 paint down through the opening 6 and fills to the rear, so to speak, the recess 7 from. The height of the rear trailing edge 27 above the plane of the substrate web 3 then essentially defines the thickness of the resulting strip 4. In the vertical position according to FIG FIG. 6b on the left side results in a high or usually maximum layer thickness of the strip 4, in analogy to the maximum opening at the rear exit edge 27. The line of contact between the coating head and the substrate web is in FIG. 6a represented by the dashed line and designated A, this line passes through the central centers of the three adjacent holes 6th

Now, if the angle of attack from the vertical position 13 as shown at the far left pivoted into a position with a lower angle 14, that is to values less than 90 ° (the pivoting takes place about the central axis of the cylinder of the coating head 1, this axis is perpendicular to Substrate running direction 12), so the rear trailing edge 27 descends down to the substrate web 3. The distance between the substrate web 3 and the rear trailing edge 27 but largely determines the resulting layer thickness of the strip 4, correspondingly results in the slightly inclined situation B, a lower layer thickness at the vertical position A.

This is shown for a slightly more extreme situation on the far right, here the inclination angle 15 is reduced so far that only a small distance between the surface of the substrate web and the rear trailing edge 27 results. In this case, the layer thickness of the strip 4 will be very thin.

It can thus be seen how the application thickness of the strip can be adjusted in a very simple yet reproducible and reliable manner over the angle of inclination of the coating head about an axis perpendicular to the direction of progression 12. For this purpose, the coating head has a rotatable about this axis suspension, ie the coating head is integrated into a unit, which allows to adjust the angle 13-15 according to the needs targeted and thus set the layer thickness over this angle. It is advantageous that the coating head is at least in that area in which the contact line for the different positions AC comes to lie (see lines in FIG. 6a ) is convex. The region 28, which is convex, may correspond to a circular cylindrical surface, but it is also possible to make the curvature of this surface differently, for example, if you want to have a linear dependence between the angle setting and the strip thickness in a particular area.

In FIG. 7 is the sake of completeness, the dependency resp. the ratio of inclination angle 13-15 to the thickness of the layer 4 again shown here for a coating head according to the embodiment according to FIG. 4 , Here, too, it becomes apparent how, depending on the angular position, the rear exit edge 30 has a different height above the substrate web 3 and correspondingly also results in a different thickness of the strip 4. In addition to reducing the height of the exit edge 30 above the substrate web 3, in this example a change in the angle of attack is accompanied by a tapering of the exit width.

Another embodiment of such a coating head is in a view obliquely from below in FIG. 8 shown. The holes are also cylindrical. Here are five holes arranged side by side and right and left of this series of holes 6, there are the already mentioned above side blind milling. In this case, the remaining between the recesses 7 to the individual holes webs 8, where the surface of the coating head is at the high level, not formed as in the embodiments described above to the trailing edge, but tapered in front of the trailing edge 32 and even disappear completely, so that forms a single common exit edge 32 for all holes. For the two laterally arranged Blindfräsungen 16 but the web is continuously formed to the exit edge 32, so that a lateral boundary of the five formed by such a stripper strip is clear. In addition, the coating head according to this embodiment does not have the depressions already discussed above but in the context of this depression over each deeper into the coating head extending supply recesses 17 which have a greater lateral extent than the holes but a lower than the wells 7th

These reservoir depressions fill up with paint, much like a fountain pen, resulting in a lower speed dependence of the application weight, as will be explained in more detail below in a descriptive example.

The order quantity can be increased by increasing the milling depth.

Using specific examples, such devices will now be further documented. The essential properties of the devices per se are summarized in Table 1, the characteristics of the strips produced by such devices are summarized in Tab. 2, and in Tab. 3 is a suitable composition for a color as used for the experiments , stated. The dimensions given below correspond to the definitions given in FIG. 9 ,

Example 1: Brush with round holes

A brass round rod of 10 mm diameter and 65 mm in length was provided with 5 through holes with a diameter of 1.6 mm. The holes ran from the top through the center to the bottom of the rod and were spaced 2.0mm apart. The holes were drilled from the top to the center of the round rod, ie to a length of 5 mm, to a diameter of 2.0 mm. These holes were equipped with 60 mm long brass tubing with 2.0 mm outer diameter and 1.6 mm inner diameter and soldered. The brass tubes were alternately slightly angled at their free ends, in order to better fit tubes with 2.0 mm inner diameter and 3.0 mm outer diameter for ink supply. The coating die thus obtained corresponds to Model 6 of Table 1 (5 individual wells were realized for the preparation of 5 individual strokes).

The coating head was placed in a suitable holder and placed with the openings down on a paper web.

The fixture for such devices in each of these examples is constructed such that the device can be rotated therein about its central axis, can be moved across the substrate web transversely to the direction of travel, and lowered perpendicularly to the paper web. By the vertical lowering, it is possible to press the device onto the substrate web, which is underlaid from its underside with a counter-pressure element made of felt. The contact pressure with which the device was pressed onto the substrate web and the counterpressure element was typically 50-70 N.

The brass tubes were provided with tubes through which coating colors according to the recipe gem. Table 3 was promoted. The paper web moved at 40 m / min under the coating head. The angle of attack of the coating head was set to 90 °, ie the holes of the coating head ran at right angles to the through Paper web formed surface. This resulted in a line image of 5 juxtaposed individual bars of 1.6 mm width with a distance of 0.4 mm with over the individual bar width varying color order. The application of paint was highest in the middle of the single strokes, lower at the edges of the single strokes and tapering towards zero. By changing the angle of attack, the order quantity could be reduced, but the different application of color across the width of each individual line was preserved.

Example 2: Brush with recesses

A coating head analogous to the model mentioned in Example 1 was prepared. In addition, however, depressions in the form of channels were milled by the ink-carrying holes in the running direction of the paper web. These had a depth of 0.2 mm (penetration depth, measured from the tangential plane to the cylinder surface at the exit point of the bore), a width of 1.8 mm and a length of 1.4 mm. Under these conditions, starting from each bore, a recess with a straight outlet edge over its entire width results. The individual wells are separated in the masses by webs of 0.2 mm width over the entire length to the outlet edge towards each other. The coating die thus obtained corresponds to the model 5 from Table 1. With the coating head, a paint application was produced on a moving paper web, analogously to the description under Example 1. It turned out that with an angle of attack of 90 °, a great deal of color got onto the paper web and the individual color traces had a slightly smaller width than the width of the channels. Only with a slight adjustment of the coating head, ie with slight closure of the gap formed between the outlet edge of the milling channels and the running paper web, resulted in single strokes, which corresponded fairly precisely to the width of the wells and had a uniform application of paint. In contrast to the individual lines according to Example 1, the application of paint in this example was uniform over the entire width of each individual line. Between the single strokes resulted a narrow distance of approx. 0.15 mm, which remained free of paint application. This fine distance - known as a so-called "speed camera" - is just barely visible to the naked eye and visually gives the impression of a very clear separation of colors between the individual lines. By varying the angle of attack, the application of paint could be adjusted without the distances between the individual lines changing or even disappearing.

Example 3: Brush with recesses with short webs

A coating head analogous to the model mentioned in Example 2 was prepared. The ink-carrying wells, which are separated in Example 2 on their entire length of webs with a width of 0.2 mm, but were changed in this example so that the webs the wells only to a length of 1.0 mm (measured from the center of the color-leading Bore) separated from each other. On the remaining 0.4 mm to the outlet edge, the depressions were thus no longer separated from one another by webs. The coating die thus obtained corresponds to the model 4 from Table 1. With the coating head, a paint application was produced on a moving paper web, analogously to the description under Example 1. At an angle of attack of 90 °, separate single strokes with high paint application and clearly visible distance formed. When lightly setting the coating head, i. with slight closing of the gap, which is formed between the outlet edge of the milling channels and the running paper web, the individual lines combined to a uniform, multi-colored paint application. In contrast to the single strokes according to Example 2, the individual strokes were no longer separated by a narrow distance from each other, but formed a uniform application of paint over the entire width of the 5 individual strokes. Surprisingly, the paint jobs of the individual strokes only flowed together, but did not mix at their contact lines, so that there was a very good color separation with very good contrast at the touch line. By varying the angle of attack, it was possible to adjust the color application without the color separation between the individual lines changing.

Example 4: Brush with color mixing

A coating head analogous to the model mentioned in Example 2 was prepared. However, bores and millings were offset from the axis of rotation of the coating head away from the direction of travel of the paper web by 1.4 mm to the rear. FIG. 10 shows in a) a view from below of such a coating head and in b) lateral views for a vertical angle of attack. When the device is now tilted slightly counterclockwise, the gap opens at 30 and the paint is applied. The further tilted, the stronger the paint application. The recesses thus ended exactly above the axis of rotation of the coating head with a depth of 0.2 mm. With the coating head, a paint application was produced on a moving paper web, analogously to the description under Example 1. This formed before the Paint brush each a small pile of color, so that in the adjoining areas of adjacent colors, these flow into each other and could mix with each other. With a slight adjustment of the coating head against the direction of the paper web, ie with easy opening of the gap formed between the outlet edge of the milling channels and the running paper web, resulted in a uniform, multi-colored inking. In contrast to the single strokes according to Example 3, the individual strokes were no longer clearly separated, but evenly mixed at their contact lines, resulting in a uniform color transition between the individual strokes. It was given a paint job, which gave the impression of a rainbow over its entire width. By varying the angle of attack, it was possible to adjust the application of paint without the color mixture between the individual lines changing significantly.

Example 5: Multicolored paint application with exposed line

A coating head was produced to produce a paint job consisting of 5 individual lines each 3 mm wide. For this purpose, a brass round bar of 16 mm diameter was selected and made from a coating head with the dimensions of model 1 in Table 1.

On a paper web moving at 40 m / min, a multicolored, uniform, superficial paint application consisting of 5 different colored individual lines touching each other was produced. With a compressed air nozzle was blown at a distance of about 20 cm in the direction of the coating head on the wet paint. The inner diameter of the nozzle was 2 mm, the distance of the nozzle from the paper web 10 mm, the air pressure 6 bar. The nozzle was positioned over the middle of the 5 individual strokes. Surprisingly, the multicolor paint application was almost completely displaced by the compressed air over a width of about 3 mm, so that the paper surface was almost completely uncovered. The paint application of the middle single line on which the compressed air was directed was found on both sides of the exposed area, in the form of a thin colored strip of about 1 mm width. The adjacent color stripes were also reduced in width, from the original 3 mm to about 2 mm. Only the outer two individual strips seemed unaffected in their width.

Example 6: Multicolored paint application with exposed serpentine line

Example 5 was repeated, this time an eccentric motor mounted directly on the air nozzle was switched on. It was a DC electric motor with a nominal voltage of 12 V, on the axis of which a steel disc of 4 mm thickness and 10 mm diameter was impressed eccentrically. At an applied voltage of 12 V resulted in a speed of 4000 rev / min. Accordingly, the air nozzle oscillated by the eccentric motor with a frequency of 67 Hz. With this oscillating air nozzle was blown analogously to Example 5 on the wet paint application. The wet color was displaced by the oscillating jet of air, giving a serpentine line that was virtually colorless. The width of the line was about 3 mm, the width in which the line oscillated about 8 mm, and the length of a complete oscillation about 1 cm. Table 1: Mass (in mm) of different brush models. Measurements see FIG. 9. model Diameter of brush head Wide recess Distance single stroke Milling depth of the recess Wide bridge Length bridge Length of edge bridge drilling diameter A b a z d 1 L D 1 16 2.8 3 0.3 0.2 1.5 2.17 1.6 2 16 2.8 3 0.4 0.2 1.5 2.5 1.6 3 16 2.8 3 0.3 0.2 2.5 2.17 1.6 4 10 1.8 2 0.2 0.2 1.0 1.4 1.6 5 10 1.8 2 0.2 0.2 1.4 1.4 1.6 6 10 - 2 - - - - 1.6 model Result 1 Directly adjacent single strokes with a width of 3.0 mm with moderate application of paint (about 8 g / m2) 2 Directly adjacent single strokes with a width of 3.0 mm with high paint coverage (about 14 g / m2) 3 Single strokes of approx. 2.85 mm width with fine distance (speed camera) of approx. 0.15 mm, with moderate application of paint (approx. 8 g / m2) 4 Directly adjacent single strokes with width of 2.0 mm with moderate application of color (about 8 g / m2) 5 Single strokes of approx. 1.85 mm width with fine distance (speed camera) of approx. 0.15 mm, with moderate application of paint (approx. 8 g / m2) 6 Single slices of 1.6 mm width with a distance of 0.4 mm with color application varying over the single-slit width (little color application at the edges of the individual slices, high color order in the middle of the single slices)

Tab. 3 shows a typical color effect pigment color composition for use with the proposed device. Table 3: Typical composition of coating colors for use in devices according to the invention. component mass fraction Mass fraction preferred pigment 5-20% 12% Binder (dry) 15-30% 20% Solvent / water 40-80% 60% excipients 0-15% 8th % viscosity 40-55 mPas 45 mPas

A specific composition of such a color is summarized in Tab. 4: Table 3: Composition of the color used with color effect pigments such as iridescent pigments. component Mass fraction (%) Acrylate dispersion / binder 9:50 Acrylate dispersion / binder, 39.00 self-crosslinking Water as a solvent 31.00 defoamers 1:00 Aid pH control 1:00 Auxiliaries / solvents, including 2-propanol 2:00 Color effect pigment 12:00 thickener 1:50 total 100.00 recipe viscosity Ford 4mm (s) Ford 5mm (s) Rheomat RM180 (mPas) According to Tab. 3 19 11 45

Preferably, oxidatively drying inks, particularly preferably aqueous, oxidatively drying inks are used, but it is also possible to use solvent-free, UV-drying inks.

These non-limiting examples represent only a selection of tools according to the invention for applying multi-color, superficial paint applications. Numerous variations deviating from these examples are conceivable. Basically, it turns out that with increasing individual stroke width b, ideally larger coating head diameters A are also selected. A larger coating head diameter A also allows a more accurate adjustment of the paint application (order quantity / application weight) by varying the angle of attack. A further improvement consists in that, in addition to the ink-carrying depressions, a blind milling of the same or similar depth of cut is carried out, as shown by way of example in FIG Fig. 5 / 9 is shown with the designation 16. Such Blindfräsungen 16 prevent the paper web when pressing the coating head in close proximity to the ink-carrying depressions undergoes a higher pressure, which can otherwise cause the paper web under the coating head elastically or permanently deformed, is pressed into the wells, resulting in may cause paint to run irregularly over the multi-color superficial paint application. Next it is possible, even behind the color-guiding milling to provide appropriate Blindfräsungen.

In a further preferred embodiment, additional recesses 17 are provided in the coating channels, in which an ink supply can accumulate. A coating head provided with such storage chambers has the advantage that the application of ink remains almost constant over a wide speed range, without the ink application having to be adjusted by adjusting the setting angle. For example, in accordance with a brush with the masses. Model 1 from Table 1 for painting a multicolored, superficial, consisting of 5 individual lines of 3 mm width each color wells of 1 mm depth (in addition to the cutting depth z of the coating channel) and 1.5 mm in length proven. This model delivered a uniform application of paint at a constant speed of attack in a speed range of 20 m / min to 60 m / min, while in a similar model without corresponding recesses, the inking in the range of 20-40 m / min was constant and in the range of 40 -60 m / min continuously decreased resp. had to be kept constant by adjusting the angle of attack and associated opening of the gap between the paper web and the top of the playing channel. By appropriate dimensioning, it is possible to obtain coating tools according to the invention which have their optimum operating point at industrially customary speeds of for example 60-140 m / min. Also much higher speeds, e.g. up to 500 m / min, are possible by appropriate dimensioning. With so dimensioned coating tools, it is possible, for example, to perform a superficial, multicolor paint application directly in a paper machine and not to perform only after completion of the paper on an additional finishing machine with much lower production speed. Because of the small dimensions and the high variability with respect to the speed of the coating tools according to the invention, retrofitting in existing paper machines or other existing systems is usually easily possible, in contrast to the retrofitting of other coating tools corresponding to the state of the art.

Instead of the air nozzle described in Example 5 and Example 6, the still wet, multicolored, superficial paint application can be treated with an airbrush spray nozzle. In addition to the displacement of the paint application can thus be sprayed on another color. The additional, sprayed-on paint replaces the extruded paint and may, depending on the distance of the airbrush nozzle from the paper surface, to the Blend edges more or less with the paint. Invisible, for example, ultraviolet light fluorescent formulations can also be sprayed on. It is also possible to print with an inkjet printhead in the still wet coating color and so accommodate variable information in the inking.

The coating colors of the individual lines may have, in addition to their coloring properties, further, possibly also machine-readable, properties. For example, they may have fluorescent properties by adding fluorescent and / or phosphorescent substances to the coating colors. For example, an application of color consisting of three single strokes in the colors red, yellow and blue can show the combination of colors green, blue and orange under ultraviolet light, resulting in a surprising, counter-intuitive effect. Furthermore, the colors may have magnetic properties, either due to the nature of the pigments used, or due to admixtures, for example in the form of black iron oxide or metallic nickel powder. In addition, pigments with magnetic properties can be magnetically aligned. Especially with effect pigments can be achieved very interesting effects. Examples of suitable pigments are Sun Chemical's SunGem color-changing pigments from Sun Chemical, but also metal pigments such as nickel pigments. If the substrate web is guided immediately after coating over a follower roller equipped with magnetic elements, for example permanent magnets, the pigments align with the magnet, resulting in a different color impression and / or different angular dependence of the color at these points of the coating as in places that were not in contact with a magnetic element.

The coating colors can further substances for identification may be added, such as feature substances, detection reagents, etc. Further, the coating colors substances can be added to increase the tactility, such as self-expanding pigments such as Expancel from Akzo Nobel.

Other additional properties include IR-IR fluorescence, IR-VIS up-conversion, thermochromism, photochromism, chemical reactivity to detection reagent, IR absorption.

In a preferred embodiment, the coating tools are made of brass. In a further preferred embodiment, the coating tools consist of stainless steel, for example of the quality V2A, V4A, chrome nickel steel 18/8, chrome nickel steel 18/10. The coating tools can also be hardened, nitrided, coated and / or surface-treated, they can be, for example, superficially chrome-plated or hard chrome-plated or provided with a ceramic coating such as chromium nitride, titanium carbide or diamond-like carbon. Coating tools made of harder base materials or those with appropriate surface finish are characterized by a higher abrasion resistance and thus by a longer service life.

The obtained with the inventive tools multicolor, superficial paint jobs are characterized by a particularly high level of security against counterfeiting, which u.a. from the precision with which the individual strokes of the paint job are applied. This precision results automatically from the fact that all individual strokes are applied simultaneously, in the same operation, and with the same tool.

For the adjustment of an existing, for example, 5 individual strokes of paint job 5 individual passes would be necessary on a screen printing machine. On the one hand, such a project would be extremely costly for a counterfeiter and, on the other hand, provides an unsatisfactory printing result which deviates significantly from the original obtained by the coating tool according to the invention. Since every single print run is inherently subject to tolerance deviations in the range of a few tenths of a millimeter, no color order can be obtained in which the individual lines are exactly adjacent to each other. It is even more difficult to readjust a paint application according to Example 2, which has the finest distances in the range of a few tenths of a millimeter between the individual lines. These distances are similar to the tolerances of the individual print passes and can not be readjusted true to the original. Likewise, it is not possible to reproduce a non-uniform application of paint as described in Example 1, since the application of ink in screen printing is invariable and a different color density can be readjusted at most by screening in an insufficient manner. Likewise, a rainbow-like color gradient of the individual strokes as described in Example 4 is not or only unsatisfactory nachstellt. LIST OF REFERENCE NUMBERS 1 String head 23 front zenith of 22 2 leads 24 rear zenith of 22 3 substrate web 25 Gradation in through-hole 4 Coating, stripes 5 Space, distance between 4 26 pipe 27 rear trailing edge of 7 6 Opening, bore 28 convex section of 1 7 Recess, recess 29 Counterpressure element 8th web 30 rear exit point of 7 9 Contact line A 31 Axis of the hole 6 10 Touch line B 32 trailing edge 11 Contact line C D Diameter of the opening 12 Substrate running direction D _s Diameter of opening perpendicular to the direction of travel 13 Angle of attack A 14 Angle of attack B D _p Diameter of opening parallel to the direction of travel 15 Angle of attack C 16 lateral blind milling a Distance between the openings 17 Supply recess b Width of the recess 18 front side d Width of the bridge 19 rear side l Length of the bridge 20 Peripheral surface of the cylinder L Length of the recess 21 Bore for supply lines t Depth of 7 22 Circulation line of 6

Claims (15)

1. Device (1) for the application of a color onto a substrate web (3) which is transported along a running direction (12) passing the device (1), characterized in that the device (1) comprises a surface area (28), which is convex in the running direction (12) and straight in the direction perpendicular to the running direction (12), and which can be brought into contact with the substrate web (3), and in that in the surface area (28) which is convex there is provided one, preferably at least two penetration openings (6) which are staggered in a direction perpendicular to the running direction (12) and which in case of two openings can be separately provided with color, through which the color is directly applied to the substrate web (3), wherein the amount of applied color depends on the inclination angle (13-15) between the plane of the substrate web (3) and the normal tangential plane on the surface area (28) at the position of the respective penetration opening (6).
2. Device according to claim 1, characterized in that in the region of each penetration opening (6) in the surface area (28) a depression (7) is provided, which extends the penetration opening (6) in the running direction (12) and/or against the running direction (12) with a depth (t).
3. Device according to claim 2, characterized in that the depression (7) extends the penetration opening (6) in the running direction (12) and is shallowing out.
4. Device accrding to any of the proceeding claims, characterized in that the device at least in the surface area (28) is designed as part of a circular cylinder, through the cylinder surface (20) of which the penetration openings (6) penetrate.
5. Device according to claim 4, characterized in that the device comprises a solid, preferably metal base circular cylinder, the access of which is arranged parallel to the substrate web (3) and perpendicular to the running direction (12), and in which the penetration openings (6) are provided as central penetration drillings, wherein preferably in the circular cylinder means for temperature control thereof are provided.
6. Device to any of the proceeding claims, characterized in that laterally to the penetration opening blind trimmings (16) without color guiding are provided.
7. Device according to any of the proceeding claims, characterized in that in the area of each penetration opening (6) in the surface are (28) a depression (7) is provided, which extends the penetration opening (6) in the running direction (12) with a depth (t), that the depression (7) in the running direction (12) is shallowing off, and that the depressions (7) of the respective penetration openings (6) at least in the area of a common exit edge (32) at least over a partial section are not separated by a web.
8. Method for the generation of at least two adjacently arranged, preferably separated stripes (4) or dotted lines on a web (3) using a device according to any of the proceeding claims, characterized in that the substrate (3) preferably in the form of a web along a running direction (12) is conducted across the device (1) and in contact therewith, wherein either continuously or intermittently color is applied to the substrate through the device directly through the penetration openings (6) and is subsequently dried.
9. Method according to claim 8, characterized in that on the side of the substrate (3) opposite to the device (1) a counter pressure element (29) is arranged.
10. Method according to any of the proceeding claims 8 or 9, characterized in that in the running direction (12) on the rear side (19) of the device there is provided a pressurized air nozzle, which, preferably in a manner inclined periodically perpendicular to the running direction (12) directs of a high pressure air stream onto the fresh stripe, such that a separation, preferably a waved separation, results between the stripes (4).
11. Substrate, particularly preferably security paper with at least two stripes (4) or dotted lines produced using a method according to any of the claims 8-10.
12. Substrate according to claim 11, characterized in that the stripes (4) have a width of at least 0.5mm and at most 5mm, preferably of at least 2.5mm and a distance in the range of at most 0.5mm, preferably in the range of 0.1-0.5mm.
13. Substrate according to any of claims 11 or 12, characterized in that the stripes (4) or dots are provided in a wavy form with periodic deflection perpendicular to the running direction (12).
14. Substrate according to any of the proceeding claims 11-13, characterized in that the stripes consists of a color effect pigment color, in particular with irridescent pigment, if need be in combination with other optically readable elements or machine readable elements or other auxiliary means readable elements, such as preferably pigments with specific absorption, or specific emission and/or with fluorescent pigments.
15. Use of a substrate according to any of the claims 11-14 as a security document, in particular banknote, traveling documents, identification card, visa stamp, travel document, access document, closure element, tax stamp, certificate, birth document, driver license, freight certificate, guaranty certificate, etiquette, document of value.

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