Abstract:
A method and device of embossing individually light-reflecting areas on a foil material, the method and device comprising feeding a foil material into a roller nip between a pair of rollers, wherein the pair of rollers comprises a first roller and a second roller, providing each of the first roller and second roller at their respective surfaces at least in a determined perimeter, respectively with a plurality of polyhedron-shaped positive projections and a plurality of negative projections complementary to the positive projections, whereby the plurality of positive projections are arranged according to a 2-dimensional grid. The plurality of polyhedron-shaped positive projections seamlessly and gaplessly join with those corresponding negative projections at the intended embossing of the foil material, hence enabling a homogeneously jointed embossed polyhedron-like shape in the foil. The method and device further comprise, for the purpose of providing a plurality of light-reflecting areas on the foil material, that are intended to reflect light in line with a table of reflectivity values for the 2-dimensional grid, according to an orientation and shape of each of the plurality of light-reflecting areas, and enabling a perception by the human eye of a user, of the intended reflected light on a determined wide viewing angle covered by reflected light from any of the light-reflecting areas, a step of adjusting for each of the plurality of light-reflecting areas to be provided, an orientation and shape of the corresponding positive projection in the 2-dimensional grid, that is intended to emboss the light-reflecting area.
Abstract:
In the method for applying identification features to a packing strip in order to authenticate the processed packing, the packing strip is fed in a packing line to an embossing station, where logos of all kinds and/or codes and/or a satin finish and/or fold lines are embossed at the cycle rate of the packing machine by means of embossing rollers by deforming the packing strip, Identification: features and possibly other features are produced additionally on the packing strip on-line, in the same process step, and synchronously to the cycle rate by material removal by means of a feature setup comprising a laser installation, the packing strip having a thickness of 50 μm to 300 μm. The thus treated packing strip is subsequently further processed. Due to the fact that the feature setup for producing the identification features is provided in addition to the embossing rollers but operates in the same process step, all known embossing rollers can be used, and due to the application of lasers for producing the features, e.g. a consecutive numbering can be produced, thereby ensuring a secure authentication method without the need of changing substantially the embossing station comprising a housing with at least two embossing rolls, or lowering the processing speed.
Abstract:
In the method for manufacturing embossing rollers for a device for embossing packaging materials that comprises a set of at least two embossing rollers of which one is driven, and whereby the embossing roller set comprises a male roller having a male surface structure including structural elements and/or logo structures and a female roller having a female surface structure that is associated to the surface structure of the male roller for the common embossing operation with the male roller, the female surface structure is produced independently of a previously produced or physically pre-existing associated male surface structure. Along with a high embossing accuracy, this allows creating a very large variety of embossing structures, on one hand, and using a very large number of the most diverse materials, on the other hand, as well as reducing transverse tensions in the embossed material.
Abstract:
An embossing method allowing to emboss a material on both sides comprises feeding the foil material into a roll nip between a pair of a first roll and a second roll, providing the first roll and the second roll each with a plurality of positive projections and a plurality of negative projections of identical shaped polyhedral structures, a first subset of the plurality of positive projections being disposed with a first periodicity on a first grid in axial direction and a second periodicity on the first grid in circumferential direction on the first roll, and a second subset of the plurality of negative projections being disposed with the first periodicity in axial direction and the second periodicity in circumferential direction on the first grid interwined with the positive projections, in axial and circumferential directions respectively, and projections complementary to the first grid, on the second roll, each of the positive projections and the negative projections on the first roll during operation of the rolls and in the roll nip being surrounded on all sides by positive projections and negative projections on the second roll, the positive projections of the first roll together with alternating corresponding negative projections on the second roll forming during the operation of the rolls and in the roll nip, a first straight line substantially parallel to the axial direction, and the negative projections of the first roll together with alternating corresponding positive projections on the second roll forming during the operation of the rolls and in the roll nip, a second straight line substantially parallel to the axial direction. The positive projections and the negative projections are such that in the axial direction on the first roll each positive projection shares a lateral base border with at least one negative projection adjacent to the positive projection, and during the operation of the rolls and in the roll nip, all lateral oblique surfaces of the positive and negative projections of the first roll are just above the surface in full faced view with the corresponding lateral oblique surfaces of the respective negative and positive projections of the second roll, thereby enabling a homogeneous distribution of pressure to the material.
Abstract:
A method for embossing a first grating in a planar material, by means of an embossing body and a counter embossing body, having each a hard surface, the first grating to be embossed comprising alternating substantially parallel and straight ridges and recesses, whereby the top surfaces of the ridges are intended to weaken a direct angular reflection of light by diffuse omnidirectional reflection, thereby producing a visible contrast between the ridges and the recesses. The method comprises on the embossing body providing a first plurality of obtuse pyramids intended to emboss the recesses of the first grating by exerting pressure on a first side of the planar material, the first plurality of obtuse pyramids forming first intermitted lines (row1, row2) corresponding to the intended recesses, and the pyramids in each subset corresponding to one of the first intermitted lines, being separated from each other by a determined distance that creates a gap in the line in such a manner that each gap from a line of pyramids may be connected to a corresponding gap from an adjacent line of pyramids by an imaginary line perpendicular to both of the adjacent lines; and roughening portions of the hard surface of the embossing body, the portions being located between adjacent lines of pyramids and intersecting at least one of the imaginary lines that connect one gap from one line to the corresponding gap from the adjacent line. On the counter embossing body, the method comprises providing a second plurality of obtuse pyramids intended to emboss the ridges of the first grating by exerting pressure on a second side of the planar material opposite to the first side, during embossing the obtuse summits of the pyramid pressing the planar material against a roughened portion of the hard surface of the embossing body, thereby satinizing the top surfaces of the ridges on the first side.
Abstract:
The present application relates to a device for the mask projection of femtosecond or picosecond laser beams (2) onto a substrate surface, in which the laser beam (2) consisting of laser beam pulses is, at a location of the optical axis, formed to make laser beam pulses with an expanded laser beam cross section or laser beam pulses with a reduced laser beam cross section and said laser beam (2) has a homogeneous intensity distribution over the laser beam cross section. A stop (6) with a predetermined stop aperture geometry and a mask (7) with a predetermined mask aperture geometry are positioned in succession in the beam (2) path at the location. The device contains a field lens systemb (8) and an imaging lens (10), which are positioned in such a way that the non-diffracted and diffracted beam components of the laser beam (2) pulses transmitted by the stop (6) and the mask (7) are directed into the imaging lens (10) with a predetermined aperture with the aid of the field lens system (8) in such a way that a reduced image, accurate in every detail and having a predetermined imaging ratio, of the intensity profile generated by the stop (6) and the mask (7) is generated over the laser beam cross section of the laser beam pulses in the imaging plane. In a beam guiding variant 1, an added lens system (16), the field lens system (8) and the imaging lens (10) are positioned relative to one another in such a way that a focus (19) is generated between the imaging lens (10) and the substrate surface and, in a beam guiding variant 2, the added lens system (16), the field lens system (8) and the imaging lens (10) are positioned relative to one another in such a way that a focus (22)is generated between the field lens system (8) and the imaging lens (10). At least one vacuum cuvette, which surrounds the region of the focus (19) and of the focus (22), is present.
Abstract:
The embossing device for embossing packaging material comprises a set of embossing rollers with male die and female die rollers co-operating with one another, the surface of which is provided with texture elements, wherein the texture elements (M6R6) on the surface of the female die roller (M6), which are assigned to the texture elements (P6E6) on the surface of the male die roller (P6) are not inversely congruent by an amount of above 15 µm in axial and radial direction and the texture elements of the male die and female roller associated with one another comprise facets (F) for the purpose of local pressure elevation. A facet (F) comprises faces (FN), which with respect to the imaginary, continuous surface of the texture is inclined. With such facetted rollers, a very large variety of films can be embossed in an aesthetically appealing manner, wherein the films can be mainly employed in the tobacco and foodstuff industry.
Abstract:
The foil embossing device (1) comprises an embossing roller (2L) and two counter-rollers (3, 4), one of the rollers (2L) being driven by a drive (6) and the rollers having a configuration where the teeth, rings, or ridges project from the base cylinder, at least the embossing roller (2L) having teeth (5, 5B) that project from the base cylinder and at least partly also serve for driving the counter-roller. To increase the uniformity of the embossing of the foil, the embossing roller (2L) has a diameter (D 2 ) that is reduced by 0.02 to 0.20 mm over a certain length (S d ) that is at least the same as the width (7 d ) of the foil. The length of the reduced diameter is preferably chosen so as to exceed the width (7 d ) of the foil being printed. Due to this depression (S), such a device allows a perfectly uniform embossing of foils of any kind independently of the design of the embossing rollers.
Abstract:
A device for engraving a diffraction grating on a workpiece, comprises an optical set-up comprising alaser, a beam forming device, a beam splitting device, and a focusing head. The laser is configured tooutput a laser beam. The beam forming device is configured to control a diameter of and a lightintensity distribution in the laser beam, and output a primary laser beam. The beam splitting deviceis configured for a splitting of the primary laser beam into a plurality of split beams for theengraving. The focusing head comprises a microscope objective lens (109) configured to focus therespective split beams in respective foci on the workpiece, an auto-focusing system configured toproduce a positioning signal for adjusting and maintaining a distance between the microscopeobjective lens and the workpiece in order to maintain the respective foci of the split beams on theworkpiece and output the positioning signal; and a micro-actuator configured to receive thepositioning signal and adjust the distance between the microscope objective lens and the workpiece,whereby the auto-focusing system and the micro-actuator are operationally connected in a closed-loop. The device for engraving further comprises a positioning device configured to perform arelative positioning between the workpiece in the respective foci of the split beams, and the opticalset-up; and a controller configured to control the positioning device and the laser according toengraving instructions for the diffraction grating.
Abstract:
A method for embossing optically diffracting microstructures in a thin foil, such as used to pack at least one of the list comprising food, chocolate, chewing gum, gifts, jewellery, clothes, tobacco products, pharmaceutical products, the embossing being produced with an embossing rollers set-up comprising at least one cylindrical embossing roller and a cambered counter roller. The method comprises confining the at least one cylindrical embossing roller and the cambered counter roller in a single roller stand of relatively small outer dimensions designed to withstand a pressure for the at least one cylindrical embossing roller and the cambered counter roller; using on a surface of a first one of the at least one cylindrical embossing rollers at least one raised embossing element adapted for microstructure embossing, whereby one of the at least one raised embossing elements com- prises a platform distant at a height in a range between 5 m and 30 m above a surrounding surface of the first cylindrical embossing roller adjacent to it, and a pattern engraved on top of the platform (5), whereby the pattern comprises the optically diffracting microstructures with periodicity of gratings in the range smaller than 30 µm that produce from a diffuse or directed source of light in the visible wavelength range diffraction images with high contrast and high luminosity in a defined observation angle; and adjusting the pressure for the at least one cylindrical embossing roller on the thin foil in a range less than 80 bar relative to a platform area of approximately 100 mm 2 .