EP2656923A2 - Method and device for manufacturing a coated building component - Google Patents

Abstract

The method involves producing a relative movement between a starting material and a coating device. A coating mass is applied along a direction transverse to advance direction vertically to a coating direction of a surface to-be-coated by the coating device. The amount of the coating mass to the running and coating plane laid over a re-painted vertical surface element is controlled in dependence of the relative movement between starting material and coating device. Independent claims are included for the following: (1) device for manufacturing coated component; and (2) coated component.

Description

The invention relates to a method for producing a coated component for exterior applications in the door and gate industry, such as a sectional door panel, a tilt gate, a door or a component for a facade with integrated gate and / or integrated door, in which a relative movement between a and a coating composition, which is applied to the starting material along a coating direction running transversely to the feed direction and preferably approximately perpendicular to the surface to be coated, is applied to the starting material for producing the component and to a coating device along a feed direction.

In conventional methods, components for outdoor applications, which are coated on a surface with a colored paint or the like, are spray-painted in order to obtain the weathering resistance required for outdoor applications in a spray booth or painted in a dipping process with a protective lacquer. In such methods of application a topcoat layer is a layer thickness of more than 60 .mu.m, usually between 80 and 100 .mu.m, whose thickness is not precisely adjustable, obtained on the surface of the device. This layer thickness is usually not needed to obtain the desired weather resistance. Furthermore, paint losses occur when the protective paint is applied, since a part of the protective paint does not or does not reach the component at the desired location. These lacquer losses are esp. Particularly high in the known spraying in spray booths and amount to one third or more of the paint material used.

This not only leads to disposal problems, but also to economic disadvantages, since per surface unit of the component to be coated corresponding paint losses must be paid.

To solve these problems will be in the DE 10 2009 041 860 A1 a method for the manufacture of components and a device suitable for carrying out such methods proposed in which the protective lacquer or a weather-resistant coating material, which may also also have a high scratch resistance and has a very good UV resistance, with the aid of paint nozzles of a conventional Inkjet printer is applied to the device. As a result, a coating thickness of 6 to 7 microns is achieved, which is completely sufficient to obtain the desired weather resistance, with no appreciable paint losses occur.

In the known method, a component, which may optionally also be provided with a decorative surface, such as a print, fed to a coating station. With the coating station, an at least partially closed layer of a preferably at least partially transparent protective lacquer is applied in a continuous process to the component. By using the ink nozzles of conventional inkjet printers, it is achieved that the closed layer is composed of individual droplets which are printed on the surface by at least one print head row. Finally, the coating is cured in the known method, for example. Using UV light.

With these known methods, the disposal and economic problems of conventional dipping or spraying can be solved. Indeed It has been shown that in some cases, weather-related damage in the coating can occur.

In view of these problems in the prior art, the present invention seeks to provide methods and apparatus for producing a coated device, with which on the one hand the observed in known dipping and spraying process economic and environmental problems are solved and on the other hand, a reliable weather resistance is achieved.

According to the invention this object is achieved by a development of the known method, which is characterized essentially in that the amount of per area element of a perpendicular to the coating direction and in the course of the relative movement between starting material and coating device swept by the coating device coating layer applied coating mass in dependence of Starting material characteristic material data is controlled.

This invention is based on the finding that the problems observed in the prior art are primarily due to the fact that especially in profiled boundary surfaces of the components in the profiling no sufficient amount of the coating composition is applied so that there are gaps within the coating and as a result, there are also weather-related damage to the possibly already printed component surface. Similar problems are observed with components composed of different materials.

In the method of the present invention, these defects are eliminated by controlling the amount of the applied coating composition in consideration of material data indicative of the starting material, such as material data indicative of material data and / or material data representing a surface topology of the device.

berechnet. Die Normalmenge bezeichnet dabei die zum Beschichten einer ebenen und parallel zur Beschichtungsebene verlaufenden Begrenzungsfläche des Bauelements benötigte Beschichtungsmenge. Dadurch kann erreicht werden, daß auf zumindest einem Teil der Begrenzungsfläche des Ausgangsmaterials die gleiche Menge der Beschichtungsmasse pro Begrenzungsflächenelement aufgetragen wird.In the case of the coating of profiled components, it has proved to be particularly advantageous if the amount of coating composition applied per surface element of the coating plane depends on the surface area or surface area of a projection of the surface element on the boundary surface of the starting material is controlled along the coating direction of the covered by the surface element boundary surface element. It can thereby be achieved that, regardless of the surface topology, a desired amount of the coating composition is applied to each boundary surface element and a corresponding layer thickness is obtained. In this case, the control can be such that, taking into account a stored in a data processing system (computer) three-dimensional profile of the device in the plane of movement of the device (coating level) of the nozzle applicator (printheads) ejected amount of coating material is exactly as varied that exactly gives consistent layer thickness on the three-dimensional component surface. To calculate the ejected amount of the coating material, the angle α between the device surface and the plane of movement (coating plane) of the device is calculated from the three-dimensional model at each point, and the amount of the ejected coating compound according to the formula $$\mathrm{coating\; amount}=\mathrm{Normal\; x}\mathrm{1}/\sin \mathrm{,}\mathrm{\alpha }$$

calculated. The normal quantity designates the coating quantity required for coating a plane boundary surface of the component which runs parallel to the coating plane. It can thereby be achieved that the same amount of coating composition per boundary surface element is applied to at least part of the boundary surface of the starting material.

As will be understood from the above explanation, the material data may include the topology data representing the topology of the boundary surface to be coated, the amount of coating compound applied to the source material being controlled in response to this topology data.

In the sense of a desired reduction of the data required for the control, the topology data can be formed from the type of topology (eg cassette, bead or the like) describing type data and scaling data indicating the size of the component. It is assumed that the topology type is formed by ratio values between the individual dimensions of the profile elements determining the topology, and the size of the individual profile elements is described by the scaling data as a function of the component sizes.

When carrying out the method according to the invention, first of all a boundary surface of the component, which may already have a decorative surface, is led to a coating station and then a continuous coating layer of the coating composition, such as an at least partially transparent protective lacquer, applied in a continuous process. In this case, the closed layer is composed of individual droplets which are printed by at least one print head on the boundary surface of the device. The device can be coated untreated. However, it is also intended to provide a component already provided with a decoration, such as a print, with a coating material in order to achieve the desired weathering resistance. After application, the coating composition is cured. By printing the coating composition with the aid of a print head nozzle or a print head, both the layer thickness and the position of the individual droplets of the layer can be precisely controlled. As a result, paint losses can be reduced to a minimum, for example, to a loss of less than 1%, preferably less than 0.1%.

In the context of the invention, it has proven on the one hand and the desired reduction of the material use on the other hand particularly favorable in view of the desired weather resistance, when the coating composition with a thickness between 5 and 60 microns, esp. Between 8 and 40 microns, on the boundary surface, such as an already provided with a decorative boundary surface of a component is printed. Accordingly, the layer thickness is significantly thinner than in a conventional application by spraying.

In the context of the invention, it is also contemplated that more coating mass per boundary surface, esp. 20 to 50% more coating mass per boundary surface, is applied to individual boundary surface elements of a first boundary surface area than on the individual boundary surface elements of a second boundary surface area, so as to adapt the coating To achieve the expected weather conditions and / or the material properties of the device while avoiding an unnecessarily high use of materials. Heavily stressed areas can be better protected with a coating mass than less stressed areas.

The component may be in different form, for example. Partially plate-shaped with a substantially flat two-dimensional boundary surface, esp. Decor surface, but with certain three-dimensional structural elements, eg. B. depressions and elevations in the range of millimeters to a few centimeters. The recesses and / or elevations may be cassette or bead-like profiles.

In the following, those areas of a predominantly flat two-dimensional component are called profiled, which project from the plane either upwards or downwards. It is also intended to the use of components with punctiform profiles or groove-shaped depressions or elevations different profiling.

The component may have an at least partially profiled surface with edges or bulges, and the protective lacquer may be applied, depending on the material data representing this profiling, in the area of the edges or bulges with a greater thickness than on flat areas of the boundary surface. Especially in the area of profilings, increased protection can thus be obtained by increasing the layer thickness of the protective lacquer.

Alternatively, it is also thought to control the layer thickness in printing so that in the range of profilings exactly the same layer thickness is achieved as at the planar locations of the device by the angle of the profiled portion in response to the above-mentioned three-dimensional profile data of the device straight is compensated.

As in the known methods according to the DE 10 2009 041 860 A1 the starting material can be conveyed as a possibly profiled material web in the feed direction with respect to the preferably stationary coating device. In this embodiment, a co-moving during the movement of the web coating level is covered by the coating device.

As already mentioned above, the starting material to be coated may have a decorative surface, for example already be printed.

In order to obtain the desired weather resistance, it has proved to be particularly useful if an at least partially closed coating of the surface of the starting material is formed with the coating material. In the method according to the invention, the coating composition is composed of individual droplets which are preferably applied to the surface to be coated by at least one, more preferably two, three or more print head rows arranged one after the other in the direction of the feed path. When using two, three or more in the direction of the feed direction successively arranged printhead rows, the amount of coating material can be controlled by the successively arranged printhead rows are individually and independently controlled to dispense the coating composition.

As can be seen from the above explanation of inventive methods, the coating composition expediently comprises a printing ink and / or an at least partially transparent protective lacquer.

As in the known method according to DE 10 2009 041 860 A1 For example, in order to obtain the starting material, a metal strip may be withdrawn from a supply (coil) in a continuous process, subjected to processing such as shaping, in particular cold working, then coated, in particular printed, and possibly in a direction transverse to the direction of advance Lengths are cut.

To obtain a desired gloss value, the surface of the coating applied to the starting material can be matted. This can be achieved in a particularly preferred embodiment of the invention by irradiating the surface with preferably a wavelength of less than 200 nm, in particular about 192 nm, UV light pulses, wherein the light pulses have a duration of less than 100 ns, preferably less than 20 ns, and the surface is applied with a power of more than 10 ⁶ W / cm ² during the duration of the light pulses.

In such a process, which is also referred to as the excimer process, a microstructure is produced in the region of the surface of the coating composition which leads to the desired degree of gloss or to the desired matted impression.

As can be seen from the above explanation of methods according to the invention, a device for carrying out such methods comprises a feed device for feeding a component to be coated to a coating station, a coating station for applying a coating composition, such as an at least partially transparent protective lacquer, in a continuous process and optionally one Matting device, wherein the coating station has at least one digital printhead series, preferably two, three or more in the feed direction successively arranged printhead rows, with which the coating composition is printed by forming individual droplets on the decorative surface and optionally a station for curing preferably at least partially having transparent coating composition.

Fig. 1

eine schematische Ansicht einer erfindungsgemäßen Vorrichtung zur Herstellung eines beschichteten Bauelements,

Fig. 2

eine Unteransicht eines Druckkopfes der Vorrichtung gemäß Figur 1 und

Fig. 3

eine Detailansicht eines beschichteten Bauelements.

The invention will be explained with reference to the drawing, to which reference is expressly made with respect to all essential to the invention and in the description unspecified highlighted details. In the drawing shows:

Fig. 1

a schematic view of an apparatus according to the invention for producing a coated device,

Fig. 2

a bottom view of a printhead of the device according to FIG. 1 and

Fig. 3

a detailed view of a coated device.

A substantially plate-shaped component 1, esp. A panel of a sectional sheet, is fed to a conveyor mechanism 4 in the form of a conveyor belt of a digital printing station 2. Within the digital printing station 2 are one or more rows of digital printheads 3, which extend substantially over the entire width transversely to the feed direction of the component 1. The component 1 may have on its upper side a decorative surface which may be printed or coated in one or more colors. With the printing station 2, a protective lacquer is applied in a single pass process with the print heads 3 on a boundary surface of the component 1.

For this purpose, the component 1 passes through the digital printing station 2 at a continuous feed rate, the protective coating from the one or more print head rows 3 being applied to the surface of the component 1 in the form of small droplets. The size of the individual droplets is between 1 and 500 pl (picoliters), in particular 10 to 200 pl, whereby the volume of the individual droplets in the specified range can be varied by means of a controller. The distance from one droplet to the other, both in the X direction (feed direction) and perpendicular thereto in the Y direction, ie both in the feed direction and transversely to the feed direction, is between 1 and 300 .mu.m, more preferably between 10 and 100 microns.

Depending on the protective varnish used, which is applied from the various print head rows 3, two, three or more print head rows 3, 3 ', 3 "are used in succession in order to produce a closed surface with the protective varnish. 3 "can apply droplets of protective lacquer on the boundary surface of the device 1. Instead of the three print head rows 3, 3 ', 3 ", two or more than three print head rows can be arranged one behind the other.

In FIG. 2 is a bottom view of a print head series 3, in which individual print heads 30 are provided, which are arranged offset from one another and cover the entire width of the component 1 transversely to the feed direction of the component 1. Each printhead includes a plurality of nozzles and each nozzle can be individually controlled via electronic control to vary the droplet size or droplet volume and droplet number.

The electronic control of the digital printing station 2 is used to print the exact contours of the boundary surface of the device 1 with the resist and to prevent overspray before, behind or laterally from the device 1. Likewise, this electronic control is used to possible three-dimensional areas of the device 1, z. B. on a profiling to achieve a correspondingly higher order per area, so that there areas are produced with a larger layer thickness.

By a suitable arrangement of the individual print heads in the print head rows 3, 3 ', 3 "and a corresponding number of print head rows and a corresponding selection of the droplet volume and the number of droplets per print head, a desired layer thickness of, for example, 10 μm is achieved on the component 1.

Following the application of the protective lacquer, the component 1 is moved by means of a conveyor 5 through a drying unit 6 with a UV emitter, in which the protective lacquer layer hardens.

As an alternative embodiment, it is also possible to use a solvent-containing protective lacquer which hardens by evaporation without UV curing. A third embodiment could be a combination of a UV-curable resist containing certain amounts of solvent which must evaporate before passing through the UV-curing station. Alternatively, a water-based paint can be used, which dries purely physically without UV curing.

Another interesting embodiment results from a special curing by means of a very intense short-wave UV radiation. This process called "excimer" causes the surface of the applied protective lacquer first to harden and contract, thus giving a matt surface, before the entire lacquer layer is subsequently hardened through further final curing. This results in a desired matt protective lacquer surface, without otherwise usual matting agent in the form of particles in the protective lacquer must be mixed with.

In FIG. 3 a component 1 is shown, which has a plate-shaped or panel-shaped body 10, on the upper side of a flat decorative surface is formed, which has a bead 11 in the form of a groove-shaped recess which may extend in the longitudinal or transverse direction of the component 1. The bead 11 has at the transition to the flat decorative surface edges 12, which can be particularly mechanically stressed. Therefore, when printing the component 1, the area of the two edges 12 is printed with a greater layer thickness than the flat areas further away from the edges 12. The layer thickness at the edges 12 may be the same, thicker or more than 20%, or more than twice or three times as thick as at the thinner areas. Moreover, the beads 11 are also printed on side walls 13 and a bottom 14 with protective varnish. The protective lacquer can be applied in the thinner areas with a thickness of between 5 and 25 μm, in particular 8 to 15 μm.

The protective lacquer itself can be composed very differently; in a preferred embodiment it consists of an acrylate mixture.

The viscosity of the protective coating is preferably between 5 and 30 cSt (centistokes) at 25 ° C.

LIST OF REFERENCE NUMBERS

1

module

2

digital printing station

3

Digital print heads

3, 3 ', 3 "

Print head row

4

funding mechanism

5

Conveyor

6

drying unit

10

plate or panel-shaped body

11

Beading

12

edge

13

side walls

14

ground

30

printheads

Claims (17)

Method for producing a coated component 1 for exterior applications in the door and gate industry, such as a sectional door panel, a tilt gate, a door or a component for a façade with an integrated gate and / or door, in which a relative movement between one for producing the Component 1 is laid out starting material and a coating device along a feed direction is generated, and a coating composition which is applied along a transverse to the feed direction and preferably approximately perpendicular to the surface to be coated coating direction of the coating device on the starting material, characterized in that the amount of per surface element of a coating layer running perpendicular to the coating direction and coated by the coating device in the course of the relative movement between starting material and coating device gsmasse is controlled in dependence on the starting material characteristic material data. Method according to claim 1, characterized in that the amount of coating compound applied per surface element of the coating plane is controlled as a function of the surface area of a boundary surface element of the component covered by the surface element when the surface element is projected onto the boundary surface of the starting material along the coating direction. A method according to claim 1 or 2, characterized in that on at least a part of the boundary surface of the starting material, the same amount of the coating composition per boundary surface element is applied. Method according to one of the preceding claims, characterized in that the material data comprise the topology of the topology data to be coated and the amount of coating material applied to the starting material is controlled in dependence on the topology data. Method according to Claim 4, characterized in that the topology data are formed from type data describing the type of topology and scaling data. Method according to one of the preceding claims, characterized in that more coating mass per boundary surface, in particular 20 to 50% more coating mass per boundary surface, is applied to the individual boundary surface elements of a first boundary surface area than to the individual boundary surface elements of a second boundary surface area. Method according to one of the preceding claims, characterized in that the starting material is conveyed as a possibly profiled material web in the feed direction with respect to the preferably stationary coating device. Method according to one of the preceding claims, characterized in that the starting material to be coated has a decorative surface. A method according to claim 8, characterized in that the starting material is printed to obtain the decorative surface. Method according to one of the preceding claims, characterized in that an at least partially closed coating of the surface of the starting material with the coating material is formed. Method according to one of the preceding claims, characterized in that the coating composition is composed of individual droplets, which is preferably applied by at least one Druckkopfreihe 3, 3 ', 3 "on the surface to be coated. Method according to one of the preceding claims, characterized in that the coating composition comprises a printing ink and / or an at least partially transparent protective lacquer. Method according to one of the preceding claims, characterized in that, in order to obtain the starting material, a metal strip is withdrawn from a supply (coil) in a continuous process, subjected to processing such as shaping, especially cold working, then coated, in particular printed, and possibly cut in a direction transverse to the feed direction to predetermined lengths. Process, esp. According to one of the preceding claims, characterized in that the surface of the coating applied to the starting material is matted. A method according to claim 13, characterized in that the surface for matting is irradiated with preferably a wavelength of less than 200 nm, in particular about 192 nm, having UV light pulses, the light pulses having a duration of less than 100 ns, preferably less than 20 ns, and the surface is applied with a power of more than 10 ⁶ W / cm ² during the duration of the light pulses. Apparatus for carrying out a method according to one of the preceding claims. Component produced by a method according to one of the preceding claims.

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