Printing press

Abstract

The invention relates to a printing press (1) which is designed to apply material (2) onto a substrate (3). The printing press (1) comprises a controller (4), a transport device (5), a print head holder (6) and a print head (14) having a nozzle (7). The transport device (5) is designed to hold the substrate (3) and transport same in a transport direction (8). The print head holder (6) is designed to move the nozzle (7) about an axis (9) along an orbit which circulates the axis (9). The controller (4) is configured to control the transport device (5), the print head holder (6) and the print head (14) such that the nozzle (7) sprays the material (2) onto a region of the substrate (3) in a metered manner.

Description

[0001]Printing machine The invention relates to a printing machine designed to apply material to a substrate, a printing method for applying material to a substrate and the use of such a printing machine. A variety of different digital printing methods are available today to print on a variety of different substrates or substrate surfaces. So-called 2D digital printing methods, where 2D stands for two-dimensional, are designed to print shapes and colors or functional layers, primarily over a large area, onto substrates. Examples of such 2D digital printing methods include inkjet printing methods and laser printing methods. So-called 3D digital printing methods, where 3D stands for three-dimensional, are designed to additively print, for example, shapes, colors, objects or components onto a substrate.Examples of such 3D digital printing processes include extrusion processes, selective laser sintering processes, and selective curing processes. In additive printing, multiple layers are printed one after the other. Such a layer can also be a functional layer, for example, an electrically conductive layer. Which digital printing process is used depends on the desired appearance of the printed product, the material from which the printed product is to be constructed, the shape of the substrate, the substrate material, and the nature of the substrate. Substrates can be flat materials such as paper, foils, cardboard, plates, panels, etc., or objects with curved or structured surfaces. The substrate material can be, for example, plastic, metal, ceramic, a natural material such as cellulose-based material, or a combination thereof.The substrate can, for example, be hard and rigid or soft and flexible. 2D digital printing processes have been and are being optimized to enable the printing of shapes and colors with high resolution and high speed. Highly productive 2D digital printing processes include so-called single-pass printing processes. In such highly productive 2D digital printing processes, print heads or nozzles are normally stationary across the entire printing width, and a row of nozzles is usually followed by a curing unit. The substrate, which is usually sheet- or ribbon-shaped, is then moved under the print heads or nozzles and past them in one direction in a mostly continuous process and printed. In these processes, exactly one layer of one material can be applied to each nozzle. Depending on the substrate speed and the productivity of the nozzle, the layer thickness can vary. In order to be able to print with stationary print heads or nozzles, a curing unit is required.In order to build up multiple layers using multiple nozzles and with the substrate moving in only one direction, either multiple print heads or nozzles must follow one another in the direction of movement of the substrate. In this case, the number of print heads or nozzles arranged one behind the other must correspond at least to the number of layers to be built, which is structurally and economically complex, or the substrate must be fed into the printing process multiple times, which impairs productivity. 3D digital printing processes have been and are being optimized to enable the additive printing of 3D structures of various sizes using a variety of different materials at high resolution and at high speed. Multi-pass printing or scanning printing processes are typically used for this purpose, in which the print head is moved in multiple directions. In order to print 3D objects with great detail, it is usually necessary to print more than one layer.The number of layers per build height then corresponds to the resolution in the build direction. In scanning or multi-pass printing processes, the print head or substrate is moved multidirectionally. The 3D object is then created by applying multiple layers to a substrate. Typically, the substrate or print head must be repeatedly decelerated and / or accelerated, which impairs productivity. What is missing is an efficient printing process for printing 3D structures with high spatial resolution. In other words, what is missing is a printing process that combines the productivity of single-pass printing processes with the possibility of building multiple layers offered by scanning printing processes. The object of the present invention is to provide a printing machine and a printing process that enable the printing of 3D structures at high speed and high spatial resolution.The object is achieved by a printing press according to the features of claim 1, by a printing method according to the features of claim 13 and by a use of such a printing press according to the features of claim 15. The respective dependent claims relate to preferred embodiments of the printing press and the method. The invention relates to a printing press which is designed to apply material to a substrate which is a flat material. The printing press has a controller, a transport device, a print head holder and a print head which is held by the print head holder and has a nozzle. The transport device is designed to hold the substrate and to transport it in a transport direction. The print head holder is designed to move the nozzle along an orbit which revolves around an axis.The controller is configured to control the transport device, the print head holder, and the print head such that the nozzle sprays the material in a metered manner onto an area of ​​the substrate. According to the invention, the printing press is designed and the controller is configured such that during printing, the substrate is moved past the print head in the transport direction by the transport device, the nozzle is moved by the print head holder along the orbit around the axis, and the nozzle moving along the orbit around the axis sprays the material onto the substrate moving past the print head. The printing press is designed to receive instructions in the form of data. This data can be provided, for example, by a computer or a processing unit. The computer or processing unit can also be part of the printing press.Furthermore, the printing press is designed to use this data to control the transport device, the print head holder, the print head, and the nozzle in such a way that the material is sprayed in a metered manner onto a specific area of ​​the substrate, thus generating the printed product. To generate the printed product, the printing press includes the technical components typical of a typical printing press, such as drives or drive units, storage devices, a material reservoir and a material feed to the nozzle, sensors for monitoring the transport of the substrate, a metering device that controls the amount of material sprayed onto the substrate through the nozzle, a power connection, etc. The material sprayed onto the substrate can be a liquid.The liquid has the property that after it has been sprayed onto the substrate and applied to the substrate, it quickly transitions into a dimensionally stable state. The liquid can be composed in such a way that the transition to the dimensionally stable state can be controlled, for example, by UV irradiation of the liquid, or by heating the liquid, etc. The liquid can comprise a polymer dissolved in a solvent. The dissolved polymer can be a polymer that crosslinks upon UV irradiation. The dissolved polymer can be a polymer that crosslinks upon heating. The dissolved polymer can be a polymer that solidifies upon solvent removal or heating. The polymer can be a thermoplastic or a thermoset. In the dimensionally stable state, the shape of the material on the substrate remains stable under the action of process-related forces. The formation of a stable outer skin can be sufficient to achieve a dimensionally stable state.Process-related forces act, for example, due to the difference between the surface tension of the substrate surface and the surface tension of the liquid, or due to capillary force-based processes that cause the liquid to penetrate the substrate, or due to the transport of the substrate, or when additional material is sprayed onto the applied material after a short time, etc. Achieving a dimensionally stable state is important in order to achieve high printing speeds and high spatial resolution in the printed product. The substrate can be, for example, paper, plastic film, metal foil, cardboard, etc. The substrate can, for example, be a continuous ribbon-like material unwound from a substrate roll.The substrate can also be a conveyor belt, in particular an endless one, which is designed to hold and transport a substrate and on which a substrate can be held and transported. The substrate can be a substrate sheet or a substrate leaf. The substrate can be flexible. The controller comprises the usual technical components for a typical controller. For example, a data input and a data output. Instructions in the form of data are received by the controller via the data input. This data can be provided, for example, by a computer or a processing unit. This computer or this processing unit can also be part of the printing press. Based on the received data, the controller sends control data or control commands or control signals to the controllable devices or units of the printing press.The controller sends control commands, for example, to the transport device in order to set the transport speed at which the substrate is transported. The controller sends control commands, for example, to the transport device in order to set the transport direction in which the substrate is transported. The controller sends control commands, for example, to the print head holder in order to set the direction in which the nozzle moves along the orbit around the axis. The controller sends control commands, for example, to the print head holder in order to set the movement speed at which the nozzle moves along the orbit around the axis. The controller sends control commands, for example, to the print head in order to set the amount of material that is sprayed from the nozzle onto the substrate. The printing machine includes the data and signal connections and any interfaces for the associated sending and receiving of data.Signals. The transport direction corresponds to the direction in which the substrate is transported or moved. Holding the substrate concerns holding the substrate on a predetermined transport path. Holding the substrate in the area in which it is moved past the print head or the print head holder is of crucial importance. For high spatial resolution in the printed product, it is crucial to control the distance between the print head or nozzle and the substrate in the area in which it is moved past the print head. The transport device can be designed to transport or move the substrate continuously or discontinuously in the transport direction. For this purpose, the transport device can comprise a conveyor belt that holds the substrate, for example by attaching the substrate to or on the conveyor belt, and thus transports it. The substrate can be a piecemeal substrate.The transport device can then be designed to receive the substrate provided piece by piece, for example on a stack, in particular to unstack and pick it up from a stack. Furthermore, the transport device can then be designed to unstack the printed piece by piece substrate onto a stack. The transport device typically comprises transport rollers and / or support rollers and / or tension rollers and / or deflection rollers and / or support rollers and / or tension rollers and / or deflection rollers. Furthermore, the transport device can then be designed to receive the substrate onto the transport belt and to hold the transport belt by the transport rollers and / or support rollers and / or tension rollers and / or deflection rollers and / or support rollers and / or tension rollers and / or deflection rollers and to transport it in the transport direction towards the print head. Rollers are driven directly and rollers are carried along by the moving transport belt.The transport of the conveyor belt is based on a frictional connection between the conveyor belt and one or more conveyor rollers. This frictional connection can be achieved, for example, by tensioning the conveyor belt against a conveyor roller or by pressing the conveyor belt against a conveyor roller. The holding of the conveyor belt can be achieved, for example, by the frictional connection or a positive connection between the conveyor belt and a roller or roll. Furthermore, the transport device can then be designed to move the substrate or the conveyor belt past the print head or print head holder in such a way that the substrate or the conveyor belt can be sprayed with material. Furthermore, the transport device can then be designed to transport or move the printed substrate or the printed conveyor belt away from the print head. Furthermore, the transport device can then be designed toto transport the conveyor belt at a constant transport speed or to move it at a constant movement speed. The transport device can be designed to transport or move an endless belt-shaped substrate continuously or discontinuously in the transport direction. Furthermore, the transport device can then be designed to receive belt-shaped substrate that is provided on a spool, in particular to unwind it from the spool and receive it, and to hold it by the transport rollers and / or support rollers and / or tension rollers and / or deflection rollers and / or support rollers and / or tension rollers and / or deflection rollers and to transport it in the transport direction towards the print head. Rollers are driven directly and rollers are carried along by the moving belt-shaped substrate.The transport of the strip-shaped substrate is based on a frictional connection between the strip-shaped substrate and one or more transport rollers. This frictional connection can be achieved, for example, by tensioning the strip-shaped substrate against a transport roller or by pressing the strip-shaped substrate against a transport roller. The holding of the strip-shaped substrate can be achieved, for example, by the frictional connection or a positive connection between the strip-shaped substrate and a roller or roll. Furthermore, the transport device can then be designed to move the strip-shaped substrate past the print head in such a way that it can be sprayed with material. Furthermore, the transport device can then be designed to transport or move the printed strip-shaped substrate away from the print head.Furthermore, the transport device can then be designed to transport or move the strip-shaped substrate at a constant transport speed. The transport device comprises a transport drive for driving the rollers. By controlling the transport drive, for example, the position of the substrate on the substrate path, the transport speed at which the substrate is transported or the movement speed at which the transport belt is moved, the transport direction in which the substrate or the transport belt is transported, or the acceleration with which the substrate or the transport belt is accelerated can be adjusted. The print head is held by the print head holder and comprises a nozzle and the technical components usual for a typical print head.For example, a chamber designed to be filled with the material that is applied to the substrate, a connection from the chamber to the nozzle, through which connection material can be transported from the chamber to the nozzle, and a dosing device that controls the amount of material that is sprayed through the nozzle onto the substrate. The print head can comprise multiple nozzles. The chamber can be a cavity in the print head that is designed to store the material that is applied to the substrate. The dosing device comprises an actuatable element, the actuation of which creates pressure on the material so that a certain amount of material escapes through the nozzle and is thus sprayed onto an area of ​​the substrate. The actuatable element can, for example, be an element that can be resistively heated using an electric current or a piezo element that can be deformed using an electric voltage.By controlling the actuation of the actuatable element of the print head's dosing device, the amount of material sprayed through the nozzle onto the substrate can be adjusted. The nozzle has a cross-sectional constriction through which the material exits in the exit direction or is sprayed onto an area of ​​the substrate in the spray direction. The nozzle is arranged on the print head holder with its cross-sectional constriction so that the constriction direction is perpendicular to the axis. The print head holder is designed to hold a print head with a nozzle and move it around the axis along the orbit that revolves around the axis. The print head holder can also be designed to hold multiple print heads. The print head holder is mounted so that it can move along the orbit that revolves around the axis in such a way that the print head or nozzle can move 360° and endlessly along the orbit around the axis.The print head holder is movably mounted in such a way that the print head can assume an angular position between 0° and 360°. The print head holder can comprise a belt that revolves around the axis, with the print head being fastened to the belt. To move the print head holder around the axis, the printing press comprises a print head holder drive. By controlling the print head holder drive, the movement of the print head holder and thus the movement of the print head or nozzle can be controlled in such a way that, for example, an angular position of the print head or nozzle, a movement speed of the print head or nozzle, an acceleration of the print head or nozzle, or a movement direction of the print head or nozzle can be adjusted. The orbit can be a circular path, with the print head holder or the print head or nozzle then rotating or being rotatable around the axis.Printing is a process carried out by the printing press which, starting from an unprinted substrate, creates a fully printed substrate or even a fully printed component by applying material to the substrate. The controller can therefore control the transport device and thus the transport of the substrate. Furthermore, the controller can control the print head holder and thus the movement of the print head or nozzle around the axis and the spraying of the material onto the substrate. This allows the substrate to be moved past the nozzle moving along the orbit in a controlled manner in such a way that a specific amount of material can be applied to a specific area of ​​the substrate in a controlled manner. The substrate is moved past the print head or nozzle or print head holder at a distance from the print head or nozzle or print head holder.Because the printing machine according to the invention transports the substrate to be printed in a controlled manner during printing or moves it past the print head or nozzle or print head holder in a controlled manner, moves the nozzle in a controlled manner along its orbit around an axis, and applies material to the substrate in a controlled manner, a high printing speed can be achieved, the nozzle can be moved past the same area of ​​the substrate multiple times, and a controllable amount of material can be sprayed onto the same area of ​​the substrate multiple times. The printing machine thus provided enables the printing of 3D structures at high speed and with high spatial resolution. Printing machines are known that transport a substrate and move it past a fixed print head for printing. Such printing machines can also be designed to print 3D structures onto a substrate.For this purpose, such printing machines comprise several print heads arranged one behind the other in the transport direction of the substrate. If, for example, a 3D structure is to be printed by spraying material three times at intervals onto the same area of ​​the substrate, such a printing machine requires three print heads arranged one behind the other in the transport direction of the substrate. Alternatively, the substrate can also be fed to the printing machine multiple times. Compared to such printing machines, the printing machine according to the invention offers the advantage that it only requires one print head to print a 3D structure by spraying material three times at intervals onto the same area of ​​the substrate. Furthermore, the printing machine according to the invention offers the advantage compared to such printing machines that one and the same print head can be used to print 3D structures by spraying three times, two, four, five times, etc., interval-like spraying of material onto the same area of ​​the substrate can be printed. Because the number of spraying processes can be flexibly adjusted, even small amounts of material can be applied to the substrate per spraying process, whereby a high spatial resolution can be achieved. Alternatively, larger amounts of material can be applied to the substrate per spraying process, whereby a high printing speed can be achieved. Furthermore, printing machines are known which move a movable print head over a fixed-position substrate to be printed in order to print on it. Such printing machines can also be designed to print 3D structures onto a substrate. Compared to such printing machines, the printing machine according to the invention offers the advantage that a higher printing speed can be achieved due to the nozzle moving along the orbit and the substrate moving past the print head or the print head holder.Furthermore, the print head or the print head holder of the printing machine according to the invention does not have to be accelerated or decelerated during printing, which saves time and reduces design effort. According to one embodiment of the printing machine, the print head holder is designed to move the nozzle in synchronism with or against the substrate moving past the print head. In synchronism, the nozzle moves with the substrate, i.e. in the transport direction. The movement speed of the nozzle can be set so that the nozzle moves at a lower or higher speed than the transport speed. If the nozzle moves at a speed that is higher than the transport speed, the nozzle can be moved past a specific area of ​​the substrate several times and material can be sprayed onto the specific area at intervals.In this way, several layers of material can be built up on top of each other on the specific area of ​​the substrate. In counter-rotation, the nozzle moves in the opposite direction to the substrate, i.e. in a direction opposite to the transport direction. The movement speed can be set so that the nozzle moves at a lower or higher speed than the transport speed. This allows the nozzle to be moved past the same specific area of ​​the substrate several times and material can be sprayed onto the specific area at intervals. In this way, several layers of material can be built up on top of each other on the specific area of ​​the substrate to form a 3D structure. According to one embodiment of the printing machine, the print head holder is cylindrical, in particular elongated, and extends along the cylinder axis and along the axis.The cylindrical print head holder can be arranged and mounted in the printing press such that its cylinder axis coincides with the axis. This provides a print head holder that is efficiently movable or rotatable and can hold and move or rotate a plurality of nozzles and / or material feeds and / or curing units and / or sensors. According to one embodiment of the printing press, the nozzle is arranged on the cylindrical print head holder such that the nozzle sprays the material onto the substrate in a radial direction away from the cylindrical print head holder. This means that the nozzle is arranged on the cylindrical print head holder such that, regardless of the angular position of the print head or nozzle, it is aligned radially and with its cross-sectional constriction away from the axis or the cylinder axis.This provides a print head holder that enables efficient material supply to the nozzle or to a plurality of nozzles. According to one embodiment of the printing machine, the cylindrical print head holder has a curing unit, the print head holder is designed to move the curing unit along the orbit around the axis, and the curing unit is arranged on the cylindrical print head holder in such a way that it radiates curing radiation in a radial direction away from the cylindrical print head holder onto an area of ​​the substrate. The curing unit is held by the print head holder or arranged on the print head holder in such a way that it radiates curing radiation onto an area of ​​the substrate to which material has been applied, and that it radiates curing radiation onto this area of ​​the substrate before this area is sprayed with further material. The curing unit can be arranged downstream of the nozzle on the print head holder orbe arranged on the print head. The printing press can comprise a further curing unit which is arranged, in particular in a fixed position, downstream of the print head holder on the printing press in the transport direction. The curing unit or the further curing unit can be a UV curing unit and the curing radiation can be UV radiation. This provides a print head holder which enables efficient curing of the material sprayed onto the substrate. According to one embodiment of the printing press, the printing press is designed and the controller is configured such that during printing the nozzle is moved around the axis by the print head holder and the substrate is moved past the print head by the transport device such that the nozzle is moved past the same area of ​​the substrate at least twice and sprays the material onto the same area of ​​the substrate at least twice.This provides a printing machine that enables efficient printing of 3D structures. According to one embodiment of the printing machine, the axis extends parallel to the substrate surface and transversely to the transport direction. This provides a printing machine that enables efficient printing of a substrate essentially across the entire width of the substrate. According to one embodiment of the printing machine, the print head holder holds first additional nozzles that are arranged next to the nozzle, in a row and along the cylinder axis of the cylindrical print head holder. The first additional nozzles can be part of additional print heads. The printing machine can be designed and the controller can be configured so that different nozzles of the first additional nozzles spray the same or different material onto the substrate.This provides a printing press that enables efficient printing of a substrate that is flexible with regard to material diversity. According to one embodiment of the printing press, the print head holder has second additional nozzles that are arranged next to the nozzle, in a row and along the circumferential direction of the cylindrical print head holder. The second additional nozzles can be part of additional print heads. The printing press can be designed and the controller configured so that the substrate is moved past each nozzle of the second additional nozzles only once. This means that the print head holder can be held fixed so that the nozzles do not move. However, the printing press can also be designed and the controller configured so that the substrate is moved past at least one nozzle of the second additional nozzles at least twice.The printing machine can be designed and the controller can be configured so that different nozzles of the second additional nozzles spray the same or different material onto the substrate. This provides a printing machine that enables efficient printing of a substrate that is flexible with regard to material variety. According to one embodiment of the printing machine, the print head holder holds a curing unit in the circumferential direction between two of the nozzles. The print head holder can hold or have one or more curing units in the circumferential direction between two of the second additional nozzles. The print head holder can hold or have a curing unit in the circumferential direction between two nozzles of the second additional nozzles that are immediately adjacent in the circumferential direction. This provides a printing machine that enables efficient printing of a substrate, in particular efficient printing of 3D structures.According to one embodiment of the printing press, the transport device has a first and a second region, and the transport device is designed to transport the substrate in the first region, in particular in a transport plane, and to move the substrate past the print head holder in a curved manner towards the print head holder in the second region. During the curved movement past the print head holder, the substrate with the substrate surface onto which the material is sprayed is curved towards the print head holder or the print head and moved past the print head or the print head holder at a distance from the print head. This means that the material is sprayed onto the curved substrate surface, which is at a distance from the print head or the print head holder as it moves past. This ensures that the substrate can be printed on efficiently in a confined space.According to one embodiment of the printing press, the second region has a transport unit that provides a negative pressure, and the transport unit is designed to hold the substrate by means of the negative pressure and to move it curved past the print head holder towards the print head holder. The transport unit can have a negative pressure chamber that provides the negative pressure and a belt-shaped band with holes that encircles the negative pressure chamber, wherein the holes provide an air connection from the negative pressure chamber to the outside, so that a substrate that rests on the belt-shaped band is pressed against the belt-shaped band via the holes by means of the negative pressure and is thus held. The belt-shaped band itself can be the substrate. This means that the belt-shaped band can be printable. This ensures that the substrate can be moved curved past the print head at a distance from the print head or nozzle.The invention also relates to a printing method for applying material to a substrate which is a flat material, using a printing machine which comprises a controller, a transport device, a print head holder and a print head with a nozzle held by the print head holder. The printing method comprises the following steps: holding the substrate and transporting the substrate in a transport direction, moving the nozzle along an orbit which revolves around an axis, around the axis, and metered spraying of the material by means of the nozzle onto a region of the substrate, moving the substrate past the print head in the transport direction during printing, moving the nozzle along the orbit around the axis, and spraying the material by means of the nozzle moving along the orbit around the axis onto the substrate moving past the print head.According to one embodiment of the printing method, the printing method comprises the following step: during printing, moving the nozzle in the opposite direction to the substrate moving past the print head. The printing method can in particular comprise the following steps: during printing, moving the nozzle past the same area of ​​the substrate at least twice, and spraying material onto the same area of ​​the substrate at least twice using the nozzle, and / or transporting the substrate in a first area, in particular in a transport plane, and moving the substrate past the print head holder in a curved manner towards the print head holder in a second area, and / or providing a negative pressure and holding it and moving the substrate past the print head holder in a curved manner towards the print head holder using the negative pressure. The invention also relates to the use of a printing machine according to the invention for applying material to a substrate.The printing press and the method according to the invention are described in more detail below purely by way of example using a specific embodiment shown in the figure. It shows: Figure 1 a print head holder with several nozzles and several curing units and a strip-shaped substrate which is moved in a curved manner towards the print head holder, past the print head or the print head holder. Figure 1 shows purely schematically an embodiment of a printing press 1 according to the invention which is designed to apply material 2 to a strip-shaped substrate 3. The printing press 1 has a controller 4, a transport device 5, a print head holder 6 and a print head 14 with a nozzle 7. The transport device 5 is designed to hold the strip-shaped substrate 3 and to transport it in a transport direction 8. The print head holder 6 is designed to rotate the nozzle about an axis 9.The controller is configured to control the transport device 5 and the print head holder 6 such that the nozzle 7 sprays the material 2 in a metered manner onto an area of ​​the strip-shaped substrate 3. The printing press is designed and the controller is configured such that, during printing, the strip-shaped substrate 3 is moved past the print head holder 6 or the print head 14 by the transport device 5 in the transport direction 8, the nozzle 7 is rotated about the axis 9 by the print head holder 6, and the nozzle 7 rotating about the axis 9 sprays the material 2 onto the strip-shaped substrate 3 moving past the print head holder 6 or the print head 14. The print head holder 6 rotates in the opposite direction to the strip-shaped substrate 3 moving past the print head holder 6. The nozzles 7 shown are arranged on the print head holder 6 in such a way that they spray the material 3 in the radial direction away from the print head holder 6 or from the print head 14 onto the strip-shaped substrate 3.The print head holder 6 has UV curing units 10 and is designed to rotate the UV curing units 10 about the axis 9. The UV curing units 10 are arranged on the print head holder 6 such that they radiate UV radiation 11 in a radial direction away from the print head holder 6 onto an area of ​​the strip-shaped substrate 3. The printing press 1 can be designed and the controller 4 configured such that during printing the nozzles 7 of the print head holder 6 are rotated about the axis 9 and the strip-shaped substrate 3 is moved past the print head 6 by the transport device 5 such that the nozzles 7 are moved past the same area of ​​the strip-shaped substrate 3 once, twice or more than twice and spray the material 2 once, twice or more than twice onto the same area of ​​the strip-shaped substrate 3. The axis 9 extends parallel to the surface of the band-shaped substrate 3 and transverse to the transport direction 8.The nozzles 7 are arranged in a row and along the circumferential direction of the print head holder 6. The print head holder 6 has a UV curing unit 10 between each two of the nozzles in the circumferential direction. The transport device 5 has a first and a second region, is designed to transport the strip-shaped substrate 3 in a transport plane 12 in the first region and to move the strip-shaped substrate 3 in a curved manner towards the print head holder 6 past the print head 14 or the print head holder 6 in the second region. The second region has a transport unit 13 which provides a negative pressure and is designed to use the negative pressure to hold the strip-shaped substrate 3 and to move it concavely past the print head 6. When printing on the strip-shaped substrate 3, it is held by the transport device 5 and transported in a curved manner in the transport direction 8 towards the print head holder 6 past the print head 14 or the print head holder 6.The nozzle 7 rotates about the axis 9 and sprays a metered amount of material 2 onto an area of ​​the strip-shaped substrate 3 moving past the print head 14 or the print head holder 6. When printing a 3D structure, the nozzle 7 is moved past the same area of ​​the strip-shaped substrate 3 at least twice, and the material 2 is sprayed at least twice onto the same area of ​​the strip-shaped substrate. During printing, the strip-shaped substrate 3 is transported in a first area in the transport plane 12 and, in a second area, is moved past the print head 14 or the print head holder 6 in a curved manner towards the print head holder 6. The transport unit 13 provides a negative pressure which enables the strip-shaped substrate 3 to be held and moved past the print head holder 6 in a curved manner. The printing machine 1 comprises a further curing unit 10a, which is arranged in the transport direction 8 after the print head holder 6 on the printing machine 1.

Claims

Patent claims 1. Printing machine (1) which is designed to apply material (2) to a substrate (3), which is a flat material, comprising a controller (4), a transport device (5), a print head holder (6), and a print head (14) held by the print head holder (6) and having a nozzle (7), wherein the transport device (5) is designed to hold the substrate (3) and to transport it in a transport direction (8), the print head holder (6) is designed to move the nozzle (7) along an orbit which revolves around an axis (9) around the axis (9), and the controller (4) is configured to control the transport device (5), the print head holder (6) and the print head (14) such that the nozzle (7) sprays the material (2) in a metered manner onto a region of the substrate (3), wherein the printing machine (1) is designed and the controller (4) is configured tothat during printing, the substrate (3) is moved past the print head (14) by the transport device (5) in the transport direction (8), the nozzle (7) is moved by the print head holder (6) along the orbit around the axis (9), and, the nozzle (7) moving along the orbit around the axis (9) sprays the material (2) onto the substrate (3) moving past the print head (14).

2. The printing machine (1) according to claim 1, wherein the print head holder (6) is designed to move the nozzle (7) in synchronism or counter-synchronism to the substrate (3) moving past the print head (14).

3. The printing machine (1) according to one of claims 1 to 2, wherein the print head holder (6) is cylindrical, in particular elongated, and extends along the cylinder axis and along the axis (9).

4. The printing machine (1) according to claim 3, wherein the nozzle (7) is arranged on the cylindrical print head holder (6) such that the nozzle (7) sprays the material (3) onto the substrate (3) in a radial direction away from the cylindrical print head holder (6).Printing machine according to one of claims 3 or 4, wherein the cylindrical print head holder (6) has a curing unit (10), the print head holder (6) is designed to move the curing unit (10) along the orbit about the axis (9), and the curing unit (10) is arranged on the cylindrical print head holder (6) in such a way that it radiates curing radiation (11) in a radial direction away from the cylindrical print head holder (6) onto a region of the substrate (3).

6. Printing machine according to one of claims 1 to 5, wherein the printing machine (1) is designed and the controller (4) is configured such that the nozzle (7) is moved by the print head holder (6) about the axis (9) during printing, and. the substrate (3) is moved past the print head (14) by the transport device (5) in such a way that the nozzle (7) is moved past the same area of ​​the substrate (3) at least twice and sprays the material (2) onto the same area of ​​the substrate (3) at least twice.

7. Printing machine (1) according to one of claims 1 to 6, wherein the axis (9) extends parallel to the substrate surface and transversely to the transport direction (8).

8. Printing machine (1) according to one of claims 3 to 7, wherein the print head holder (6) holds first further nozzles which are arranged next to the nozzle (7), in a row and along the cylinder axis of the cylindrical print head holder (6).

9. Printing machine (1) according to one of claims 3 to 8, wherein the print head holder (6) has second further nozzles which are arranged next to the nozzle (7), in a row and along the circumferential direction of the cylindrical print head holder (6). 10.Printing machine (1) according to claim 9, wherein the print head holder (6) holds a curing unit (10) in the circumferential direction between two of the nozzles.

11. Printing machine (1) according to one of claims 1 to 10, wherein the transport device (5) has a first and a second region, and the transport device (5) is designed to transport the substrate (3) in the first region, in particular in a transport plane (12), and to move the substrate (3) past the print head holder (6) in a curved manner towards the print head holder (6) in the second region.

12. Printing machine (1) according to claim 11, wherein the second region has a transport unit (13) that provides a negative pressure, and the transport unit (13) is designed to hold the substrate (3) by means of the negative pressure and to move it past the print head holder (6) in a curved manner towards the print head holder (6).Printing method for applying material (2) to a substrate (3), which is a flat material, with a printing machine (1) which comprises a controller (4), a transport device (5), a print head holder (6) and a print head (14) held by the print head holder (6) and having a nozzle (7), comprising the steps of holding the substrate (3) and transporting the substrate (3) in a transport direction (8), moving the nozzle (7) along an orbit which revolves around an axis (9) around the axis (9), and metered spraying of the material (2) by means of the nozzle (7) onto a region of the substrate (3), the method comprising the steps of moving the substrate (3) past the print head (14) in the transport direction (8) during printing, moving the nozzle (7) along the orbit around the axis. Spraying the material (2) by means of the nozzle (7) moving along the orbit around the axis (9) onto the substrate (3) moving past the print head (14).

14. Printing method according to claim 13, wherein the printing method comprises the step of moving the nozzle (7) in the opposite direction to the substrate (3) moving past the print head (14) during printing, in particular and comprising the steps of moving the nozzle (7) past the same area of ​​the substrate (3) at least twice during printing, and spraying the material (2) onto the same area of ​​the substrate (3) at least twice by means of the nozzle (7), and / or transporting the substrate (3) in a first area, in particular in a transport plane (12), and moving the substrate (3) past the print head holder (6) in a curved manner towards the print head holder (6) in a second area, and / or providing a negative pressure and holding the substrate (3) by means of the negative pressure and moving the substrate (3) past the print head holder (6) in a curved manner towards the print head holder (6).

15. Use of a printing machine (1) according to one of claims 1 to 12 for applying material (2) to a substrate (3).

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