DE202004018710U1 - Device for producing a structured surface and workpiece with a structured surface - Google Patents

Abstract

Workpiece with a structured surface,
With a carrier material (2),
- With a first coating (22) and
- With a second coating (24) having a spatially varying distribution of the order amount.

Description

The The invention relates to a device for producing a structured surface and a workpiece with a structured surface.

The Invention is preferably used in plate-shaped workpieces, is but not limited to this. Because all workpieces can with a structured surface be provided. Nevertheless, the invention will be described below with reference to a Plate production, especially for floor coverings or furniture parts explained.

Especially finds the present invention application to workpieces Wood materials, in particular made of chipboard, medium-density Fiberboard (MDF), High Density Fiberboard (HDF), Hardboard and Oriented Strand Board panels (OSB panels). Likewise, the invention can be applied to workpieces that made of a different material. For example, to do so Glass, plastics, mineral materials and electronic workpieces such as Called boards. in principle However, the invention is not limited to an application in certain Limited materials.

As well is the thickness of the workpiece no restrictive Feature. On the one hand, the workpiece can be a thin MDF board a few millimeters thick be educated. On the other hand, the workpiece can be several inches thick be. The condition is only one coating applied can be and the workpiece is manageable.

A textured paint surface So, for example, applies to plate-shaped workpieces, in the area of floors or furniture parts be used. For this purpose, the surface to be painted in cheaper First primed after appropriate pretreatment, then with a Decor printed and final provided with a transparent sealing layer. The angry Layers can depending on the requirements, consist of several layers, for example, a multi-color print or a particularly solid To realize sealing layer. The sealing layer preferably exists from a hardenable Lacquer, in this case is referred to below by a sealing varnish.

Between the processing steps for applying the various layers go through this workpiece usually called dry tunnels in which one at least partial crosslinking of the layers by the action of heat and / or Radiation energy brought about becomes. The hardening and possibly drying is carried out in the usual way by means of UV radiation or by electron radiation. In addition, there are also heat radiation techniques known.

Around the surfaces thus produced To give a more authentic look may be the sealant layer be structured. These structures can be matched to the decor For example, a surface with wood decor usually becomes one Obtained pore structure.

To Two main methods are known.

The method called "chemical pore" uses printing inks or release agents due to their wetting properties cause the sealing layers applied to them to tend show off, resulting in a less thick or no sealing layer forms and thus in the cured state of the coating gives a structure. The release agent can even displace the subsequently applied sealing varnish, the subsequent hardening bursts open, so that the desired Pore structure forms as cracks in the surface.

A "mechanical pore" is obtained by after the order of the sealing layer these only partially crosslinked and then before final hardening the layer using an embossing roller or a structured press belt, the desired structure pressed becomes.

With Both of these methods can be optically and haptically achieve only unsatisfactory structures in coated surfaces.

Of the The present invention is therefore based on the technical problem to provide a device with the economically an achieved improved structure in a coated surface can be. Likewise, the technical problem underlying a workpiece with a corresponding surface structure to provide.

The previously pointed out technical problem is first through a device to carry out a method for producing a structured surface a workpiece solved, wherein a first coating is applied to the surface of the workpiece and in which a second coating on the first coating with a spatial varying distribution of the order quantity is applied.

According to the invention it has been found that the structure is not in an existing layer, in particular Of which an at least partially cured layer must be introduced, but that by a selectively varying order of a second coating, the surface structure can be produced. Due to the varying application rate of the second coating, a surface structure is created which haptically and / or visually gives the viewer an impression that corresponds to a surface texture to be imitated. For this purpose, the first coating and the second coating are at least partially optically transparent in a preferred manner.

Spatially varying Order quantity generally means that the order quantity of the second Do not coat evenly over the to be coated surface is distributed but that zones or areas with higher order quantity and Zones or areas with less or no order amount provided are. Because the application of the method is not on two-dimensional surfaces limited is, is generally a spatial, i.e. spoken three-dimensional distribution.

Not necessary, but it is preferred that the first coating a full-surface coating which, in particular, also has sealing properties for the underneath arranged surface of the carrier material of the workpiece.

in the The following will be described in the description of the embodiments of the invention each spoken by a first coating and a second coating. It is emphasized that the first coating and also the second coating each itself from at least two separately applied Layers or partial layers can exist. In particular, a second coating consist of two or more sub-layers, whose Structures overlap and / or complement each other.

When For example, a typical application of the method may be one wood surface by a suitably colored decor one below the first and second coating arranged pressure layer and by a mimicking the wood decor adapted structuring of the second coating or imitated.

To indicates the varying distribution of the application amount of the second coating preferably a linear structure, in particular typical for the surface structure a wooden surface is.

As well may vary the order of application of the second coating a sheet-like structure optionally also having a linear structure is connected.

It There are two possibilities the surface structure embody. On the one hand, the surface structure of the second coating as negative surface structure be generated. These are actually to be imitated as a deepening Surface structures, For example, pores, designed as surveys. This structure, its grandeur for example below 1 mm, in particular below 0.5 mm, can not by a human hand and / or optically be differentiated from a structure with depressions. A negative surface structure is generated in particular by a line structure.

One Advantage of the negative, so sublime pore lies in the better Hygiene properties of the surfaces compared to a recessed pore surface. Because at the sublime structures Much worse impurities accumulate, as it in depressions the case is. Especially because of the small size of the pores can be recessed Pore structures, as well known in laminate flooring panels known are, very bad or not cleaned at all. Therefore, plates are with negative, raised pores for one Use spaces Very suitable for use with special hygiene requirements.

In Preferably, the thickness of the structures of the second coating is below 0.1 mm. There are also thicknesses depending on the order quantity Range of less than 0.01 mm or even 0.005 mm possible. Also These small thicknesses are recognized as a textured surface. The smaller the structure thickness can be, the lower the Order quantity to be set. Not least for cost reasons usually the lowest possible Thickness advantageous.

To the others, the surface texture can be positive be configured, with raised surface parts actually imitate asperities represent. In this case, the surface structure is preferred with a flat surface structure generated, which may leave open line-shaped spaces, the then appear as pores, for example.

It is also advantageous if the spatially varying distribution of the application amount is designed so that in the areas in which a survey is to be formed, a maximum coating amount is applied, while in the areas in which no survey is to be formed, no coating is applied. This type of order is particularly suitable for a replica of a wooden surface. Further Embodiments are interposed by choosing average coating values instead of the maximum or minimum coating. This embodiment can be used in particular for a replica of a stone surface for tiles.

before is the nature of the first coating and the second coating not explained in detail, since it depends preferably on the surface structure to be generated. Therefore can the material and the way of applying the first and second Coating optionally adapted to the requirements of the surface become.

The in particular means that any layer-forming materials for the second coating can be used. Below is the Procedure predominantly based on the preferred use of a paint or sealer described. Nevertheless, the present invention is not on limited. So can For example, synthetic resins, plastics or natural substances how minerals are used to make the second coating.

In In most of the examples previously described, the second coating becomes in the form of a particularly viscous liquid applied. To a complete melt away the structure is therefore preferably the second Coating after application at least partially cured. there it is further preferred, the time interval between application to minimize the second coating and curing. Will against it the second coating in the form of a predominantly solid material, For example, in the form of a dispersion applied, so can the Work step of curing omitted and, for example, only one drying step required be.

A particularly preferred embodiment of the surface is achieved by that the second coating is applied as a paint. It can in particular an otherwise used as a sealing varnish lacquer used become.

A preferred property of the paint is that the paint easy is to be processed and also represents a layer-forming material.

To Furthermore, preference is given to using a so-called high-solid lacquer. A high solid paint has a high content of solids or solids, the volume fraction can be between 75 and 100%. The solvent content is for example in the range of 3-25%. Partially, the Description 100% high solid lacquer used, although before application of the paint, albeit a small amount of solvent got to. Because of the high proportion of solids produced after curing, so after evaporation of the solvents a noticeable layer of these solids. Because of the low solvent content the high solid paints are more viscous than other paints and can hardened faster become. Because only a small amount evaporates, it can harden as well calculated with a smaller shrinkage of the applied structure which benefits the exact definition of structuring. Furthermore is preferably the same paint as in the underlying layer used because of it because of the same application properties a problem-free processing possible is. It is precisely these properties that make the application of high solid Coatings in the construction of the second coating advantageous.

Of the Another advantage of using high-solids paints is that that little or no solvent problems expected during processing, and that almost the entire applied material on the workpiece remains and not a noticeable part is removed during drying. Another advantage of high solid paints is that the viscosity in wide Limits is adjustable. Likewise, it is advantageous that when curing the high solid paints, a high degree of crosslinking, the second Coating is therefore very stable. Overall, in the application of high solid paints a second coating can be produced that a resistant and forms permanent structured surface of the workpiece.

Especially The paint can be provided with nanoparticles to a particular to have good sealing property. Therefore, the described Method are used in particular for painted surfaces. The Abrasion resistance of the paint layer, due to the addition of the Nanoparticles arise, in particular, benefits surfaces that are strong Are exposed to stress. This applies in particular to floor panels.

In more preferably, the first coating is also used as a sealing lacquer applied so that the two coatings seal the underneath surface represent. The sealing varnish of the first coating is between 65% and 95%, in particular, cured to 85% before the second coating is applied. This degree of curing on the one hand allows that the second sealing lacquer layer well with the first sealing lacquer layer combines. On the other hand, good resistance of the applied Structure of the second coating achieved so that these are not zerfliest.

There are several possibilities, the optical effect of the structure of the second coating emphasized. On the one hand, an adjustment of a different gloss level of the second coating can be selected in comparison with the gloss level of the first coating. It has been shown that regions with increased layer application on the finished workpiece surface achieve a higher degree of gloss, whereas areas with reduced layer application cause a reduced degree of gloss on the finished workpiece surface.

on the other hand The color of the second coating may be different to the color the first coating selected to emphasize the visual impression of the structured surface. This means that the coatings are either transparent or at least partially or completely may be opaque. Depending on the application of the method, therefore, the surface structure in a per se transparent and the view through the coatings therethrough or in itself the optical surface design be formed forming mold.

Especially it is possible, that the second coating as a pigmented UV-curable Paint is applied to the gloss level and / or the color of the second Adjust coating. This is indeed for a suitable curing a UV light source required, however, in this embodiment the process achieved particularly good effects.

For the implementation of the Method, it has proved to be advantageous that the second coating by a roller with a structured, in particular imprinted or grained surface is applied. Thus, you can Techniques are already being used in other applications already established. The roller has zones at its periphery Inclusion of more or less sealing varnish on the to be sealed surface is applied. According to the viscosity of the sealing varnish used and the time between application and hardening is no or only a partial flow of the applied paint layer done, which then deepens zones with lower order quantity and zones with higher order quantity arise raised in the finished surface.

A further embodiment of the method for producing a structured surface on a workpiece used in place of the applicator roll arrangement described above a digital applicator for applying the second coating. A digital application device means that the device individually controllable deliver the sealing lacquer to the surface of the workpiece can.

In particularly preferably, a jet printing technique can be used which are far, especially in so-called inkjet printers is common. In this blasting technique are by separately controllable Nozzles small Generates liquid droplets, which are sprayed in a narrow grid on the surface.

As well For example, the digital application device can use the so-called laser printing technology be used. In this technique, using a laser beam a roll surface prepared so that the roll surface only at predetermined locations the Sealing varnish absorbs, then to the surface of the workpiece to give up again.

Of others can Means for generating a dot distribution for driving the digital application device be provided. Thus, that of the digital application device be applied structure based on a point distribution. These means are preferably a computer or memory elements, in which the point distributions are calculated or read out and processed.

at Another embodiment of the method is an optical scanning device for detecting the surface pattern provided the workpiece. The scanning device can be used as a scanner, line camera or area camera be educated and fulfilled the purpose, continuously or partially the surface of the workpiece capture. This surface information is transferred to the computer, then from the measurements of the optical scanning a calculated point distribution to be generated.

Becomes then continue synchronization between the optical surface of the Workpiece and the structuring of the second coating desired, so may from the speed the movement of the workpiece to be machined relative to the scanning device and the distance to the digital applicator a time delay can be calculated. Thus it can be achieved that the optically detectable structure the surface of the workpiece and the haptically detectable surface of the second coating at least partially agree. This structure is also referred to below as a synchronous pore.

before is the application of the second coating by means of roller arrangements and described using digital application techniques. Thereon However, the method described is not limited. It is also conceivable, the material of the second coating in another Way to apply.

For example This can be liquid during application Material is dripped or sprayed on to a more or less dense random distribution of the material to achieve. As well can be a tough one liquid be applied in streaks, in which the liquid from above the workpiece arranged openings, if necessary flows out at intervals.

Furthermore the second coating can also be applied as a foil, which are deposited in a separate step on the first coating and attached, for example, glued. Also in this way a structured second coating can be produced.

The surface of the workpiece below the two coatings described can be done in a variety of ways be coated.

• – eine mindestens eine Schicht aufweisende Haftvermittlerschicht,
• – eine mindestens eine Schicht aufweisende Grundierungsschicht,
• – eine mindestens eine Schicht aufweisende Walzgrundschicht,
• – eine mindestens eine Schicht aufweisende und das Dekor darstellende Druckschicht,
• – eine mindestens eine Schicht aufweisende korundhaltige Lackschicht und
• – eine mindestens eine Schicht aufweisende Schleiflackschicht.

In a further refinement of the method, therefore, one or more of the following coatings of the surface can be applied, for example under the first coating, which in particular determine the optical structure (decoration) of the surface of the workpiece:

• A bonding agent layer having at least one layer,
• A primer layer comprising at least one layer,
• A rolling base layer having at least one layer,
• A printing layer comprising at least one layer and representing the decor,
• - At least one layer having corundum paint layer and
• - An at least one layer having abrasive paint layer.

As is apparent from the above description of the method, It has been shown that it is possible is through a quantitatively tuned Application of a second coating, in particular a sealing medium with subsequent hardening, to obtain a high-quality structuring of the coated surface.

Become the different order quantities in the sealing layer chosen in coordination with the decor, a structure can be achieved that matches the decor. For example, a surface can thus be provided which a wood decor with a coordinated pore structure. The Material that is to be represented by the decor is thereby improved imitated. One can also speak of a so-called synchronous pore speak. It is again preferred that the first coating and the second coating are at least partially transparent, so that the underlying decor through the two coatings remains recognizable.

It but it is also possible to dispense with a decor, in particular a decorative print layer and by selecting a suitably colored sealant layer consisting of at least a first coating and at least a second coating a colored surface with any structure to accomplish.

In Preferably, using UV radiation curing paints for the used previously described paint coating. But they are too all other lacquers or synthetic resins applicable for the application of the method according to the invention, so far with these the demands made on the finished workpiece surface such as. Scratch resistance, abrasion resistance or adhesion can be achieved.

before the method is especially for one painted surface a workpiece been described. However, this is the subject of the present invention not limited. Because the second coating can also be applied to a laminate coating first coating are applied. In this case, a in itself not for the sealing of the surface required second coating, in particular as a lacquer layer applied, whose actual purpose is the structuring of the surface.

The Application of the method can therefore also take place on a substrate, which is not directly provided with a decor, but in the one applied printed paper, in particular laminated. Such Papers are known from the laminate production. This mostly impregnated with urea / melamine resins Papers are subjected to elevated temperature and pressure the substrate to a composite body pressed. By the method described above, these workpieces can then with an additional Layer are provided, so that the composite body with a surface structure is provided.

to Improvement of the properties of the coating materials used can These must be provided with various additives and fillers. So can Hard particles may be provided around the scratch and abrasion resistance to improve or so-called W absorber, which causes premature yellowing the surface prevent.

The technical problem indicated above is also solved according to the invention by a workpiece with a structured surface, in particular produced according to a previously described method. The workpiece has a carrier material, a first coating and a second coating tion, which has a spatially varying distribution of the order quantity.

Further Embodiments of the workpiece are in the subclaims given, each with the same characteristics and benefits as described by the method described above have been.

The Above indicated technical problem is inventively so by a device for producing a workpiece with a structured Surface, in particular for carrying out the previously described method solved. The device has a Processing station for applying a first coating the surface of the workpiece and a processing station for applying a second coating on the first coating with a spatially varying distribution the order quantity.

Further Embodiments of the device according to the invention are in the dependent claims in the following description of the preferred embodiments be explained in more detail.

in the Below, the invention will be explained in more detail with reference to embodiments, including on the attached Drawing reference is made. In the drawing show

1 a schematic representation of an apparatus for producing a structured surface on plate-shaped workpieces with an applicator roll arrangement,

2 a schematic representation of an applicator roll for a direct application of a second coating,

3 a schematic representation of an applicator roll for an indirect application of a second coating,

4 a schematic representation of an applicator roll with a profiled doctor blade for a direct application of a line-shaped second coating,

5 a schematic representation of an apparatus for producing a structured surface on plate-shaped workpieces with a digital application device,

6a . 6b a schematic representation of a first embodiment of a structured surface,

7a - 7c a schematic representation of a second embodiment of a structured surface and

8th a schematic representation of a third embodiment of a structured surface.

1 shows in a schematic form an apparatus for producing a structured surface on a workpiece, in the present case as a plate 2 is trained. When the application of the method to plate-shaped workpieces is described below, this does not mean that the present invention is limited to such workpieces.

Several plates 2 are on a conveyor belt 4 arranged, which are individually fed sequentially to different processing stations. The conveying direction is in 1 indicated by an arrow and runs from left to right. Instead of several single plates 2 It is also possible to machine a large-area workpiece or an endlessly produced workpiece, which after the processing described below in individual plates 2 is divided.

In the 1 shown processing stations 6 and 8th have in common that each with a coating is applied. In the present embodiment, the two coatings consist of a same paint. However, the invention is not limited thereto, so it can also be applied by the processing stations coatings of different materials. Thus, in addition to paints and resins or synthetic resins can be applied.

It is also possible that only the workstation 8th is provided, which has a second coating on one already with the workpiece 2 bonded first coating such as a laminate coating applies.

In the processing station 6 a first substantially full-surface coating is applied from a lacquer. For this purpose, the processing station has an applicator roll 10 Apply a uniform layer of varnish to the surface of the plates 2 applies. In the downstream post-processing device 12 the applied coating is at least partially dried and cured. The post-processing device 12 For example, by means of a hot air flow or by means of electromagnetic radiation, in particular UV radiation, the drying and curing cause. For this purpose, the post-processing device 12 corresponding means for generating the hot air flow or the radiation.

In the processing station 8th is by means of an applicator roll 14 a coating of a paint applied directly, the order quantity varies spatially. This leads to an intended structuring of the upper lacquer layer. The spatial structuring of the lacquer layer is produced in particular by a gravure roll, in the surface of which different sections having different levels are formed.

usual Way becomes the surface a gravure roll by means of pricking or engraving edited to individual wells, so-called wells, usually in rhombic form, to produce with different depths. When printing is a Paint or varnish applied, which is absorbed in the wells is going to, while of transferring on another medium partly from the depressions on the surface of the Media to be delivered.

In the downstream post-processing device 16 Then the last applied coating is at least partially cured, so that the structurally different structuring is fixed before it balances again due to bleeding. In this curing step, it may also lead to a possibly incomplete curing of the underlying, in the first processing station 6 applied coating come.

It has proven to be advantageous if the two paint layers consist of the same paint, since thereby the bonding of the two coatings is relieved. In contrast, however, can also be different Composition of the two coatings are chosen, for example the surface effects to emphasize and reinforce the structuring. The differences can be for example in the color of the two coatings or in the degree of gloss consist.

2 shows an applicator roll 14 using the direct printing process the paint on the surface of the plate 2 applies. The arrow again indicates the direction of movement of the plate 2 at. The structured lateral surface 15 the applicator roll 14 (the structuring is not visible in detail) picks up the paint, with the amount of paint L over a squeegee 17 is set. By a rotation of the applicator roll 14 then the paint is structured, so with a spatially varying distribution on the surface of the plate 2 transferred directly. Therefore, this method is also called direct printing method.

3 shows the same roller 14 , which is not used in this embodiment as a direct application roller, but the adhesive paint initially on a separate applicator roll 19 transmits, which preferably has an elastic, preferably rubberized roll surface. From the applicator roll 19 then the one from the roller 14 transferred paint on the surface of the plate 2 applied. The remainder of the lacquer L becomes the further rotation of the applicator roll 19 with the help of another squeegee 21 before again varnish from the roller 14 is transmitted. This process is also called indirect printing process.

4 shows a further embodiment of the applicator roll arrangement. Here are on an applicator roll 14 with a smooth surface by means of a profiled squeegee 17 applied separate paint strands. After application on the surface of the plate 2 then results in a line structure. The density of the lacquer strands, their distances and their diameter can be freely selected by setting the profiling. In addition, by a preferably oscillating movement of the doctor blade transversely to the direction of movement of the plate 2 creating a wave-like arrangement of the lacquer strands on the plate surface possible.

Another embodiment of the doctor blade assembly is that instead of a profiled doctor blade 17 two identically profiled doctor blades are provided. If both doctor blades are aligned, the lacquer strands are applied to the roll surface. If the two squeegees are shifted against each other, the order of the paint strands is interrupted. By a selective shifting against each other interrupted structures can be created.

5 shows a further embodiment of an apparatus for producing a structured surface on a plate 2 in which, instead of the above-described applicator roll arrangement, a digital application device 30 is provided for applying the second coating. In the present example, a jet printing technique is used, which is particularly widespread in so-called inkjet printers. In 5 below the applicator a short dash is drawn in which indicates the row of droplet jets. Here it is assumed that the applicator transversely to the direction of movement of the plate 2 line by line apply the paint. Likewise, it is also possible to apply a droplet to each surface in order to increase the speed of application.

Furthermore, there is a computer 31 as a means for generating a dot distribution for controlling the digital application device with the application device 30 connected. The computer 31 prepares digital control information and transfers it to the job device.

As in the other application devices, a post-processing device is followed by the digital application device 32 to dry and at least partially cure the previously applied second coating.

Furthermore, an optical scanning device is advantageously provided 34 provided the surface pattern of the surface of the plate 2 or possibly the first coating to be detected. During operation, the optical scanner detects the surface and transmits the acquired data to the computer 31 , The computer 31 then calculates from the readings of the optical pickup 34 a point distribution to be generated. This is then with the digital application device 30 applied as a second coating.

The Optical scanning device can be used as a scanner, as a line scan camera or designed as an area camera be. The goal in any case is that the optical scanning device the surface with a resolution recorded or evaluated the recorded data with a resolution, with the digital order device the structured second Should apply coating.

By one of the conveying speed of the plate 2 and the distance between the optical pickup 34 and the digital application device 30 dependent time delay can also be achieved that the digital application device 30 applying the structured second coating to the surface such that the surface structure at least partially coincides with the optical pattern. In other words, in this way a synchronous haptic and optical surface design of the plate 2 be achieved.

In 1 is further shown that the surface of the plates 2 before the application of the two coatings described above by means of the processing stations 6 and 8th by means of two further processing stations 18 and 20 each provided with a coating. This can be in particular lacquer layers with which a two-tone surface, a decor is produced. The processing stations 18 and 20 In a similar manner, as previously described, application devices and post-processing devices, without being described in more detail here.

The pre-painting represents a particularly preferred embodiment, because the surfaces produced therewith are completely painted and can thus be produced in a plant. The pre-painting in the two processing stations 18 and 20 but can also be replaced by any other coating system. In particular, a plant for laminate coating or veneer coating can be provided, which subsequently passes through the processing stations 6 and 8th be provided with the coatings described above.

A further preferred embodiment of the device is that the two processing stations 18 and 20 apply a surface-varying pattern, such as a wood decor. These are the two application rollers of the processing stations 18 and 20 synchronized to apply matching and complementary color patterns. In addition, the gravure roller 14 provided with a surface engraving whose image also with that of the processing stations 18 and 20 matches printed images. Furthermore, the rotation of the gravure roll 14 so with the rotation of the application rollers of the processing stations 18 and 20 synchronizes that spatially varying distribution of the second coating with that through the processing stations 18 and 20 matched printed image. Thus, a synchronized with the printed pattern varying distribution of the top coat layer, such as a pore structure suitable for wood decor can be achieved.

Of course, even more processing stations to the described processing stations 18 and 20 to be added.

6a and 6b show a first embodiment of a structured surface of a plate 2 , On the material of the plate 2 is a first coating 22 from a paint or other material has been applied over the entire surface. On the first coating 22 is still a second coating 24 has been applied, which has a spatially varying distribution of the order amount. The variation in this case means a pore structure that is intended, for example, to imitate a wood decor. The pores are here as elongated recesses 26 formed, as in particular from the magnification in 6b results. The second coating 24 So it consists of the areas that are not formed as a depression.

The pores 26 are shown in this schematic representation substantially rectangular in cross-section with slightly rounded edges. In practice, however, a distribution that differs more clearly from the rectangular shape can occur since the areas of the second coating 24 in the edge areas of the recesses 26 partially dissolve before curing. Rounded corners are therefore at real recesses 26 expected.

In the 6a shown spatial distribution of the order amount of the second coating results in a pore structure in which the pores did in particular depressions in the coating 24 represent. Such a structure can also be called a positive surface structure.

The 7a to 7c show a similar surface structure of a second coating 24 in which the pores are called elevations 28 are formed. Such a surface structure may therefore be referred to as a negative surface structure. Because the actually to be expected as a depression pores are formed as elevations. As has already been mentioned above, the size of the structures is so small that in a normal viewing by a user the negative surface structure can not be distinguished from a positive surface structure.

The second coating 24 So it consists of the areas that have been applied as surveys, so for example as negative pores. The surface coverage of the second coating is therefore considerably lower than in the embodiment according to FIG 6a and 6b ,

Especially 7b shows in an enlargement the cross-sectional shape of the negative pore. As already to the cross section of the positive pore after 6a and 6b has been described here, the cross-sectional shape of the pore is shown with rounded edges. This form is to be expected if the applied paint partially dissolves before curing to the forming edges.

7b shows a continuous course of the survey or the negative pore 28 , 7c in contrast, shows a within the applied negative pore 28 existing substructure. This substructure consists of individual spaced individual elevations 29 arising from the application techniques described above.

On the one hand, this substructure may arise during application by means of an embossed or engraved roll shell surface, that is to say if the surface has individual wells which in each case emit the adhering lacquer. Since the wells are spaced, the dispensed droplets are also on the first coating 22 spaced apart and thus lead to the substructure.

On the other hand, such a structure can arise when using a digital application device. Because even here the paint in droplet form on the first coating 22 applied, so depending on the distance of the droplets on the surface of the first coating 22 forms a more or less pronounced substructure.

In 7c The individual surveys have been shown rectangular. However, here too, the above-mentioned effect of the occurring partial deliquescence before hardening applies, so that it can be assumed that the individual elevations will at least partially dissolve one another. This effect is all the more so as that the individual surveys are arranged much closer together than for the previously described entire pore structure after 7b the case is.

8th shows by way of example a geometric pattern of the spatial varying distribution of the application amount of the second coating. The illustrated pattern is a diamond pattern that has recessed and raised diamonds. In this form of spatial distribution, it is not possible to distinguish between a negative or a positive structure that has the same number of raised and recessed areas.

in the Following is a possible Investigation method be given, with a surface structure as described above. It depends on it It is also possible to dissolve and recognize structures in the range of 0.01 mm.

The Method is based on the principle of the known light-section method with optical triangulation, whereby a relative movement of measuring cell and Measured object is required. The way it works is the surface area to be measured with a suitable light source (laser) line to illuminate and with the help of a surface camera to detect the light stripe imaged on the object. there are the surface normals the lighting and the camera under a triangulation angle tilted to each other. The camera then sees the projection line as one, the contour of the specimen replicating contour line, from their coordinates and the associated positions a three-dimensional Profile can be calculated. The resolution of the known techniques achieves an accuracy in the vertical direction of less as 0.1 μm.

With The help of such a procedure can be the structured surface of the second coating to be examined and analyzed.

As well is an analysis of surface structures possible with the help of microscopes.

Claims (28)

Workpiece with a structured surface, - with a carrier material ( 2 ), - with a first coating ( 22 ) and - with a second coating ( 24 ), which is a spatial Lich varies distribution of order quantity. Workpiece according to claim 1, characterized in that the varying distribution of the application amount of the second coating ( 24 ) a linear structure ( 26 . 28 ). Workpiece according to claim 1, characterized in that the varying distribution of the application amount of the second coating ( 24 ) forms a sheet-like structure. Workpiece according to one of claims 1 to 3, characterized in that the surface structure of the second coating ( 24 ) forms a negative surface structure. Workpiece according to one of claims 1 to 3, characterized in that the surface structure of the second coating ( 24 ) forms a positive surface structure. Workpiece according to one of claims 1 to 3, characterized in that the raised portions of the second coating ( 24 ) have a substructure consisting of individual spaced individual elevations ( 29 ) consists. Workpiece according to one of claims 1 to 6, characterized in that the second coating ( 24 ) consists of a lacquer, preferably a sealing lacquer, in particular provided with nanoparticles. Workpiece according to one of claims 1 to 7, characterized in that the first coating ( 24 ) consists of a lacquer, preferably a sealing lacquer, in particular provided with nanoparticles. Workpiece according to one of claims 1 to 8, characterized in that the gloss level of the second coating ( 24 ) is formed differently from the gloss level of the first coating. Workpiece according to one of claims 1 to 9, characterized in that the color of the second coating ( 24 ) is formed differently from the color of the first coating. Workpiece according to one of claims 1 to 10, characterized in that below the first coating ( 22 ) one or more of the following coatings of the surface is provided: a primer layer having at least one layer, a primer layer having at least one layer, a printing layer having at least one layer and representing the decor, a rolling base layer having at least one layer, a primer layer at least one layer containing corundum lacquer layer and - at least one layer having abrasive lacquer layer. Workpiece according to claim 11, characterized in that the second coating ( 24 ) is applied with a spatial distribution that matches that with the under the first coating ( 22 ) applied coating is printed on printed decor. workpiece according to one of the claims 1 to 10, characterized in that a laminate coating is provided as the first coating. Device for producing a structured surface on a workpiece ( 2 ), - with a processing station ( 6 ) for applying a first coating to the surface of the workpiece and - with a processing station ( 8th ) for applying a second coating to the first coating with a spatially varying distribution of the application amount. Apparatus according to claim 14, characterized in that the processing station ( 8th ) and possibly the processing station ( 6 ) a post-processing device ( 12 . 16 ) for drying and / or curing the second coating and optionally the first coating. Apparatus according to claim 14 or 15, characterized in that the processing station ( 8th ) an applicator roll ( 14 ) for a varying distribution of the application amount of the second coating. Apparatus according to claim 16, characterized in that the application roller ( 14 ) performs a direct printing method or an indirect printing method. Apparatus according to claim 16 or 17, characterized in that the application roller ( 14 ) has a linear surface structure. Apparatus according to claim 16 or 17, characterized in that the application roller ( 14 ) has a sheet-like surface structure. Device according to one of claims 16 to 19, characterized in that the application roller ( 14 ) a surface structure for producing a having negative surface structure of the second coating. Device according to one of claims 16 to 19, characterized in that the application roller ( 14 ) has a surface structure for producing a positive surface structure of the second coating. Device according to one of claims 16 to 21, characterized in that the applicator roll ( 14 ) has a structured or screened, in particular embossed or engraved roller. Device according to one of claims 16 to 21, characterized in that the applicator roll ( 14 ) has a roller with a smooth rubberized or metallic lateral surface, wherein a profiled doctor blade is provided for distributing the sealing lacquer on the lateral surface. Device according to claim 14 or 15, characterized a digital application device for applying the second Coating is provided. Device according to claim 24, characterized in that that the digital application device as an inkjet printer or is designed as a laser printer. Device according to claim 24 or 25, characterized in that means for generating a point distribution for activation the digital application device are provided. Apparatus according to claim 26, characterized in that - an optical scanning device for detecting the surface pattern of the surface of the workpiece ( 2 ) and that the means for generating a point distribution from the measured values of the optical scanning device calculate a point distribution to be generated. Device according to one of claims 14 to 27, characterized in that at least one processing station ( 18 . 20 ) are provided for applying one or more coatings under the first coating of the surface.