Method for producing a structure on a surface

Abstract

A method for manufacturing a structure on a surface of a workpiece (1) is disclosed, the method having the following steps:applying a liquid base layer (2) onto the surface of the workpiece (1);spraying on at least one droplet (3) into the not yet congealed base layer (2), wherein the at least one droplet (3) at least partially, preferably completely, penetrates into the base layer (2);fixing the base layer (2); andat least partially removing the at least one droplet (3).Further, a second method having the following steps is disclosed:spraying on at least one droplet (3) onto the surface of the workpiece (1);applying a liquid base layer (2) onto the surface of the workpiece (1), wherein the base layer (2) flows around the at least one droplet (3) and preferably at least partially covers the at least one droplet (3);fixing the base layer (2);at least partially removing the at least one droplet (3).Finally, a device for performing the methods is disclosed.

What is claimed is: 
     
         1 . Method for producing a structure on a surface of a workpiece ( 1 ), the method having the following steps:
 applying a liquid base layer ( 2 ) onto the surface of the workpiece ( 1 );   spraying on at least one droplet ( 3 ) into the not yet congealed base layer ( 2 ), wherein the at least one droplet ( 3 ) penetrates at least partially, preferably completely, into the base layer ( 2 );   fixing the base layer ( 2 ); and   at least partially removing the at least one droplet ( 3 ), wherein   the at least partially removing of the at least one droplet ( 3 ) is performed by a first mechanical removal, preferably of 1 to 50 µm, especially preferred of 5 to 10 µm, of the cured base layer ( 2 ), preferably by means of a grinding device, optionally followed by a mechanical brushing out of the such exposed at least one droplet ( 3 ) and/or by a thermic heating and sucking of the then re-liquefied at least one droplet ( 3 ).   
     
     
         2 . Method for producing a structure on a surface of a workpiece ( 1 ), the method having the following steps:
 spraying on at least one droplet ( 3 ) onto the surface of the workpiece ( 1 );   applying a liquid base layer ( 2 ) onto the surface of the workpiece ( 1 ), wherein the base layer ( 2 ) flows around the at least one droplet ( 3 ) and preferably at least partially covers the at least one droplet ( 3 );   fixing the base layer ( 2 ); and   at least partially removing the at least one droplet ( 3 ), wherein   the at least partially removing of the at least one droplet ( 3 ) is performed by a first mechanical removal, preferably of 1 to 50 µm, especially preferred of 5 to 10 µm, of the cured base layer ( 2 ), preferably by means of a grinding device, optionally followed by a mechanical brushing out of the such exposed at least one droplet ( 3 ) and/or by a thermic heating and sucking of the then re-liquefied at least one droplet ( 3 ).   
     
     
         3 . Method according to  claim 1 , wherein 
 the at least one droplet ( 3 ) congeals when contacting the workpiece ( 1 ) and/or the base layer ( 2 ) or imbibes a solid aggregate state, and/or wherein   the at least one droplet ( 3 ) is fixed in a separate step or together with the base layer ( 2 ).   
     
     
         4 . Method according to  claim 1 , wherein 
 by the spraying on the at least one droplet ( 3 ) into the before applied liquid base layer ( 2 ), at least one recess is brought in, wherein the at least one recess is preferably completely filled by the at least one droplet ( 3 ), and/or wherein the layer thickness of the base layer ( 2 ) at the place where the at least one droplet ( 3 ) has been sprayed on changes.   
     
     
         5 . Method according to  claim 1 , wherein 
 several droplets ( 3 ) are placed one above the other at the same spatial place in the liquid base layer ( 2 ) and/or on the workpiece ( 1 ) so that, before the applying and/or before the fixing of the base layer ( 2 ), a compound droplet ( 3 ) results.   
     
     
         6 . Method according to  claim 1 , wherein 
 before the spraying on of the least one droplet ( 3 ), a further processing step in which a solidification of the base layer ( 2 ) takes place insofar as the base layer ( 2 ) comprises a higher viscosity than upon its application onto the workpiece ( 1 ), however, it is not yet congealed, takes place.   
     
     
         7 . Method according to  claim 1 , wherein 
 the at least partially removing of the at least one droplet ( 3 ) takes place by means of mechanical and/or chemical and/or physical procedures, wherein, optionally, also material of the base layer ( 2 ) is removed.   
     
     
         8 . Method according to  claim 1 , wherein the at least one droplet ( 3 ) is re-liquefied by means of a solvent after the fixation of the base layer ( 2 ). 
     
     
         9 . Method according to  claim 1 , wherein 
 the at least one droplet ( 3 ) consists of a material, preferably of an acrylate mixture, which cannot be stimulated to cure, in particular to polymerise, by UV radiation.   
     
     
         10 . Method according to  claim 1 , wherein 
 the liquid base layer ( 2 ) encompasses the at least one droplet ( 3 ) in such a manner that an orifice having a smaller area then a vertically upward projection of the at least one droplets ( 3 ) remains in the base layer ( 2 ) or that the liquid base layer ( 2 ) completely encompasses the at least one droplet ( 3 ).   
     
     
         11 . Method according to  claim 1 , wherein 
 the base layer ( 2 ) is fixed in such a manner that an area comprising the at least one droplet ( 3 ) has a different hardness grade, preferably of at least a factor 2, with respect to an area without applied droplets ( 3 ).   
     
     
         12 . Method according to  claim 3 , wherein 
 the at least one droplet ( 3 ) undergoes a reduction of volume during congealing or fixing.   
     
     
         13 . Device for producing a structure on a surface of a workpiece ( 1 ), the device comprising:
 an application unit ( 100 ) configured to apply a liquid base layer ( 2 ) onto a surface of the workpiece ( 1 );   a dispensing unit ( 200 ) configured to spray on at least a droplet ( 3 ) into the not yet congealed base layer ( 2 ) and/or onto the surface of the workpiece ( 1 );   a fixation unit ( 300 ) configured to fix the liquid base layer ( 2 );   a processing unit configured to at least partially remove the at least one droplet ( 3 ); and   a control unit configured to control the device according to the method according to  claim 1 .   
     
     
         14 . Device according to  claim 13 , comprising: 
 a transport unit ( 500 ) configured to feed the workpiece ( 1 ) to the application unit ( 100 ), the dispensing unit ( 200 ), the fixation unit ( 300 ) and the processing unit, wherein the transport unit ( 500 ) preferably comprises a conveyor belt.   
     
     
         15 . Device according to  claim 13 , wherein
 the application unit ( 100 ) comprises an application roller ( 101 ), a digital print head and/or a digital nozzle beam, and/or   the dispensing unit ( 200 ) comprises a digital print head ( 201 ) and/or a digital nozzle beam, and/or   the fixation unit ( 300 ) comprises a UV light source ( 301 ), a heat source and/or a flow source, and/or   the processing unit comprises a brush ( 401 ), a suction device, a removal device, a device for dispensing a substance onto the base layer ( 2 ) and/or the droplets ( 3 ), the substance being configured for a chemical reaction with the base layer ( 2 ) and/or with the droplets ( 3 ), and/or a heat source.   
     
     
         16 . Method according to  claim 2 , wherein
 the at least one droplet ( 3 ) congeals when contacting the workpiece ( 1 ) and/or the base layer ( 2 ) or imbibes a solid aggregate state, and/or wherein   the at least one droplet ( 3 ) is fixed in a separate step or together with the base layer ( 2 ).   
     
     
         17 . Method according to  claim 2 , wherein 
 several droplets ( 3 ) are placed one above the other at the same spatial place in the liquid base layer ( 2 ) and/or on the workpiece ( 1 ) so that, before the applying and/or before the fixing of the base layer ( 2 ), a compound droplet ( 3 ) results.   
     
     
         18 . Method according to  claim 2 , wherein 
 the at least partially removing of the at least one droplet ( 3 ) takes place by means of mechanical and/or chemical and/or physical procedures, wherein, optionally, also material of the base layer ( 2 ) is removed.   
     
     
         19 . Method according to  claim 2 , wherein the at least one droplet ( 3 ) is re-liquefied by means of a solvent after the fixation of the base layer ( 2 ). 
     
     
         20 . Method according to  claim 2 , wherein 
 the at least one droplet ( 3 ) consists of a material, preferably of an acrylate mixture, which cannot be stimulated to cure, in particular to polymerise, by UV radiation.   
     
     
         21 . Method according to  claim 2 , wherein 
 the liquid base layer ( 2 ) encompasses the at least one droplet ( 3 ) in such a manner that an orifice having a smaller area then a vertically upward projection of the at least one droplets ( 3 ) remains in the base layer ( 2 ) or that the liquid base layer ( 2 ) completely encompasses the at least one droplet ( 3 ).   
     
     
         22 . Method according to  claim 2 , wherein 
 the base layer ( 2 ) is fixed in such a manner that an area comprising the at least one droplet ( 3 ) has a different hardness grade, preferably of at least a factor 2, with respect to an area without applied droplets ( 3 ).   
     
     
         23 . Method according to  claim 16 , wherein 
 the at least one droplet ( 3 ) undergoes a reduction of volume during congealing or fixing.   
     
     
         24 . Device for producing a structure on a surface of a workpiece ( 1 ), the device comprising:
 an application unit ( 100 ) configured to apply a liquid base layer ( 2 ) onto a surface of the workpiece ( 1 );   a dispensing unit ( 200 ) configured to spray on at least a droplet ( 3 ) into the not yet congealed base layer ( 2 ) and/or onto the surface of the workpiece ( 1 );   a fixation unit ( 300 ) configured to fix the liquid base layer ( 2 );   a processing unit configured to at least partially remove the at least one droplet ( 3 ); and   a control unit configured to control the device according to the method according to  claim 2 .