Method for cutting glass member and glass member

Abstract

To provide a method of cutting at least partially a glass member into at least two glass sub-members along a cutting plane, and a glass sub-member which is manufactured and / or can be manufactured by a method which is based upon the present invention.SOLUTION: The present invention relates to a method of cutting a glass member 11 into at least two glass portions along a cutting plane, and the method includes the steps of: preparing the glass member 11; controlling one linear focus in a glass body 13 so that a tensile stress zone 17 and / or at least two compressive stress zones 19 are formed in a glass material; introducing initial damage for forming a crack in the glass member in the tensile stress zone 17 and / or between the two compressive stress zones 19; and developing the crack in the glass material to form the cutting plane, and cutting the glass member 11 along the cutting plane.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for at least partially cutting a glass element along a cutting plane into at least two glass part elements and in particular to a glass part element produced and / or producible by the method according to the invention.

[0002] Background technology In glass production and processing, it is regularly necessary to cut glass elements, such as glass sheets, along precisely defined cutting planes, the observance of a predefined extension direction of the cutting plane being of great importance, for example with regard to the compatibility of the glass part elements obtained after cutting with further components.

[0003] In addition to perfect cut surfaces in this respect, specifications often also specify requirements for low roughness values ​​and high strength of the cut surfaces and their edges. The reason is that glass part elements, whose cut surfaces and edges have low roughness on the one hand and high strength on the other hand, are generally relatively insensitive to external influences. This makes it possible to a certain extent, completely or at least partially, to prevent external damage of the cut surfaces and their edges from occurring in the first place and to prevent possible existing defects from progressing into the glass or initial defects due to the action of external stresses (mechanical, thermal, ...) from leading to the progression of cracks and thus to the abandonment of the glass part.

[0004] In this case, the general method of carrying out the cleavage step is known to those skilled in the art from the prior art, e.g. 2 These include thermal laser beam separation (TLS), mechanical scribing, laser scribing or laser-based thermal cutting (laser-based thermal shock cutting). Laser-based thermal cutting is typically performed using CO 2The aim of these methods is to develop an initial crack in a glass element by means of thermomechanical stresses induced by a laser. However, what is common to all these methods is that they do not allow any or only insufficient control of the crack path inside the glass. As in the case of mechanical scribing, if the surface is not provided with a guide line, the actual cut surface extending into the depth region can only be predicted inaccurately. The same is observed for the laser methods, whose action is not essentially limited to the outside of the glass material.

[0005] In the laser filamentation method, which is also known to the skilled person, individual regions of the glass element to be cut are removed along the desired cutting surface by a laser. For example, in order to form hollow spaces, so-called drill holes, in the interior of the glass element, through holes are drilled at the desired locations and material is forced into the side wall of the cylindrical surface. The prepared glass element is then finally cut by breaking, for example mechanically or by cleavage, along the perforation lines formed by the perforation holes. However, due to the perforation holes, the roughness value of the subsequent cut surface is also high. However, it has been observed, among other things, that during the break, the crack line may deviate from the perforation line and may proceed away from the perforation line. This may therefore result in a cut surface that does not correspond to the extension direction that is actually desired. It has been found that the perforations produced by the laser are precisely the starting point of microcracks that may proceed from the individual drill holes into the interior of the glass element and thus affect the extension direction of the cut surface.

[0006] Cutting methods are also known in which laser filamentation is followed by an etching step instead of breaking, where in addition to the aspects due to the laser step, the preparation and execution of the required etching step is laborious and therefore generally relatively time-consuming and cost-intensive.

[0007] Ablation methods, in which an ablation spot is used to repeatedly remove glass material, are also known to those skilled in the art, but such methods are often time consuming to perform and therefore uneconomical, and moreover, such processes often result in large damage zones in the glass member.

[0008] Furthermore, the cut surfaces and edges of glass members cut by known methods have a relatively high roughness and a relatively low edge strength, which leads to instability of the cut surfaces and edges, and therefore to an increased susceptibility to breakage as mentioned at the beginning.

[0009] The object of the present invention is therefore to provide a method which overcomes the drawbacks known from the prior art and allows for a safe, reliable, efficient and economical cutting of glass parts, in particular in which an improved determination of the cutting surface in the entire depth range is possible, the resulting cutting surface, including its edges, has a low roughness value and the edges have a high strength. It is also an object of the present invention to provide a glass part element having a side or edge with a high strength. The term edge is synonymous here with the cutting surface.

[0010] The object of the present invention is to provide a method for at least partially cutting a glass member along a cutting plane into at least two glass part members, the method comprising: - providing a glass element having at least one glass body comprising at least one glass material; - controlling at least one line focus within the glass body such that at least one tensile stress zone and / or at least two compressive stress zones are formed in the glass material along the cut surface; - causing initial damage to form at least one crack in the glass material in the tensile stress zone and / or in the glass material between two compressive stress zones, respectively; and - propagating a crack in the glass material within the tensile stress zone or between two compressive stress zones to form a cut surface along which the glass member is cut. The problem is solved by proposing a method having the following:

[0011] The present invention is thus based on the unexpected finding that, by first forming a tensile stress zone in the glass material along the desired extension direction of the subsequent cut plane, the cut plane can be particularly reliably generated in the glass material and controlled over the entire depth region of the glass material. An initial damage can then cause a crack to form and propagate in the tensile stress zone, which is "channelized" by the tensile stress zone in accordance with the set extension direction of the cut plane. The compressive stress zone at least partially surrounds the tensile stress zone, which effectively prevents the crack from leaving the tensile stress zone and propagating into the surrounding glass material. One tensile stress zone or two compressive stress zones (relatively) may be sufficient for crack guidance, respectively.

[0012] In this case, the linear focus makes it possible to modify the entire depth region of the glass body, so that a tensile stress zone is formed practically throughout the entire depth region together with a compressive stress zone surrounding the tensile stress zone. The linear focus particularly advantageously focuses the light energy in a specific region, i.e., in a depth region of the glass body, in which case a modification in the form of stress changes can be particularly advantageously brought about in the glass material in the depth region of the glass body. In particular, however, the linear focus can be formed everywhere in the glass body with constant properties without altering the quality, so that the glass material can be modified uniformly everywhere in the glass body.

[0013] It is particularly worth emphasizing that, as long as only one of the different stress zones in the glass material can be formed according to the desired extension direction of the cut surface, any extension direction of the cut surface can in principle be achieved on the basis of the method according to the invention, but this also makes possible highly complex cut surfaces that are impossible or only very difficult to achieve with conventional methods.

[0014] Whereas in conventional cutting methods based on the formation of cavities, random crack extension directions can result in cutting parallel to the perforation line, in whole or in part, on one side or the other, rather than along the originally intended perforation line, this is not the case in the present invention due to the setting of stress zones according to the present invention.

[0015] Precisely in terms of processing steps under clean room conditions, the invention has the added particularly important advantage that the entire cutting method is carried out without material removal, so that no contamination of the material itself or the surroundings occurs, whereas in the case of mechanical cutting, shell-shaped fractures and / or chips would inevitably occur, especially in the case of relatively complex cut geometries.

[0016] It was furthermore found, quite unexpectedly, that the strength of the cut surface and its edges is in part significantly increased by the method according to the invention compared to conventional cutting methods, which the inventors attribute to the fact that the compressive stress zone, so to speak, stabilizes the subsequent cut surface, thereby apparently preventing multiple damage from occurring at the cut surface and edges or even progressing into the glass material.

[0017] At the same time, the inventors have also confirmed that the method according to the invention allows the roughness of the cut surface and its edges to be reduced compared to the results of the previously known techniques. The inventors explain this by the fact that due to the precise setting of the extension direction of the cut surface by the tensile stress zone, the cutting of the glass element proceeds in a so-called orderly manner, so that fewer errors occur. Due to this so-called gentle cutting, the cut surface is relatively smooth and therefore relatively less rough.

[0018] It is furthermore particularly advantageous in the method according to the invention that the edges are preloaded without the use of liquid in this case, but rather the edges are already inherently preloaded.In a particularly preferred embodiment, therefore, it is ensured that the cutting surface and / or the edges of the cutting surface are inherently preloaded, in particular after cutting the glass part along this cutting surface.

[0019] The proposed method thus contributes in many ways to improving the cutting process and results, since, based on the control of the stress field, a significantly improved control over the crack extension and thus the cut surface is achieved, while also improving the roughness and strength values.

[0020] At the same time, the method according to the invention can be realized by conventional means and can therefore be easily integrated into existing installations, i.e. the special method for cutting the glass sheet and releasing the cut pieces of the glass sheet can be operated particularly efficiently and with particularly good results.

[0021] In other words, it can be summarized that according to the present invention, by passing the laser continuously and / or intermittently one or more times throughout the entire depth, a predetermined area in the glass material of the glass body can be modified simply and precisely, so that in the next step, the glass member can be cut along a precisely set plane.

[0022] Thus, according to the invention, it is possible to modify the glass element itself, for example a glass plate or glass pane, having a thickness of 0.6 mm or more, in particular 0.6 mm to 10 mm, preferably 0.6 mm to 5 mm or 3 mm to 5 mm, more preferably 0.6 mm to 3 mm, more preferably 0.6 mm to 2 mm or most preferably 0.6 mm to 1.5 mm, over its entire depth in a single pass. For example, the glass element may have a thickness of 1 mm to 50 mm, 1 mm to 40 mm, 1 mm to 30 mm, 1 mm to 20 mm or 1 mm to 15 mm. Alternatively or additionally, the glass element has a thickness of more than 1 mm, more than 5 mm or more than 10 mm.

[0023] In other words, the invention in principle makes it possible to process a glass element by producing a modification, for example a tubular or cylindrical modification, in a first step. In a further step, the glass element can be cut or a closed outer contour can be produced by applying mechanical and / or thermal stresses in the material. An inner contour can also be produced in principle, for example, by subsequent etching. The damage, as is generally referred to, develops in the tensile stress zone produced by the modification, by a method applied in a further step.

[0024] In one preferred embodiment, alternatively or supplementarily to the first aspect of the invention, it may be envisaged that at least one line focus is controlled within the glass body such that at least one tensile stress zone and two or more compressive stress zones are formed in the glass material along the cut surface.

[0025] In this case, the skilled person understands that if something is done "along" the cut plane, for example the formation of stress zones such as compressive and / or tensile stress zones, the cut plane does not necessarily have to be present at this point (yet), since the cut plane only becomes fully formed in the two glass part pieces after cutting of the glass piece, but in this case instead refers to the planned cut plane.

[0026] Thus, in a preferred embodiment, the method alternatively or additionally comprises the step of determining a planned cutting plane for the glass member.

[0027] In this case, everything that pertains to the cut surface in the as yet uncut glass piece is also pertaining to the planned cut surface, e.g., in this case, controlling the line focus includes forming at least one tensile stress zone and / or at least two compressive stress zones in the glass material along the planned cut surface.

[0028] In this case, the skilled person understands that the linear focus must be formed essentially inside the glass body. In this case, this includes the case where the linear focus is formed completely inside the glass body, i.e. no linear focus is formed outside the glass body at all. In this case, the linear focus is preferably formed inside the glass body up to the surface of the glass body, or the linear focus is formed inside the glass body with a certain distance from each surface, for example a maximum of 2 μm, a maximum of 1 μm or a maximum of 0.5 μm. However, it is of course also included that the linear focus is indeed formed inside the glass body, but also extends outside the glass body. In fact, this even constitutes a preferred case.

[0029] The object of the present invention is achieved according to a second aspect by a method for at least partially cutting a glass member along a cutting plane into at least two glass part members, the method comprising: - providing a glass element having at least one glass body comprising at least one glass material; - controlling at least one line focus within the glass body such that at least one tensile stress zone and at least two compressive stress zones are formed in the glass material along the cut surface; - causing initial damage to form at least one crack in the glass material in the tensile stress zone and / or in the glass material between two compressive stress zones, respectively; and - propagating a crack in the glass material within the tensile stress zone or between two compressive stress zones to form a cut surface along which the glass member is cut. The problem is solved by proposing a method having the following:

[0030] In this case, reference is made to the comments relating to the first aspect of the invention, which also apply correspondingly here.

[0031] Thus, in a preferred embodiment of the second aspect of the invention, the method alternatively or additionally comprises the step of determining a planned cutting plane of the glass member.

[0032] Alternatively or additionally, in the first and second aspects of the invention, (i) the compressive stress zones are at least partially spaced apart from one another; (ii) the tensile stress zones are at least partially surrounded by at least one compressive stress zone; (iii) the controlling of the linear focus comprises forming in the glass material at least one tensile stress zone and at least two compressive stress zones along the cut surface, the tensile stress zones being at least partially surrounded by at least one of the two compressive stress zones; (iv) the controlling of the linear focus comprises moving the glass member relative to the linear focus, whereby the linear focus can be preferably formed in at least a plurality of respective different localized regions, in particular sequentially or consecutively; (v) the controlling of the linear focus leads to the non-destructive formation of stress zones, resulting in a "soft index change" type modification in the glass material, and / or the linear focus is formed sequentially along the cut surface in a plurality of respective different localized regions of the glass material, whereby the glass material in each of these localized regions is modified with respect to its local stress value, The spacing of the localized regions is selected such that at least immediately adjacent localized regions at least partially overlap, so that a continuous path is formed by the modifications induced in the glass material along the cut surface, preferably due to the overlap of modifications of a plurality of localized regions a plurality of different stress zones are formed and / or the individual localized regions are preferably linear in at least one transverse section of the glass element, which preferably extends parallel to at least one surface of the glass body, in particular including at least one cut edge of the cut surface, and / or perpendicular to the optical axis of the light beam. and / or (vi) in at least one cross-section, preferably in all cross-sections, parallel to the surface of the glass body, the localized regions are circularly shaped and / or each two immediately adjacent localized regions (a) have a center-to-center or center-to-center spacing smaller than the maximum diameter of their extension length, in particular the extension length in the cross-section, and / or (b) have a center-to-center or center-to-center spacing smaller than 1000 nm, preferably smaller than 100 nm, further preferably smaller than 10 nm, most preferably smaller than 1 nm.

[0033] Since the control of the linear focus proceeds without destruction in the sense of cavities, separate phases or cracks in the glass body or glass material, it is particularly advantageously possible to separate, on the one hand, the determination of the extension direction of the cutting surface by the formation of a tensile stress zone, and, on the other hand, the execution of the physical cut by inducing and propagating a crack in or within the tensile stress zone, so that more control can be achieved over the cutting process compared to conventional methods.

[0034] For example, in known cutting methods, the setting of the extension direction is already accompanied by a weakening of the material, which can also be the starting point for uncontrollable damage to the remaining glass material, whereas in the present invention it is possible to carry out a modification of the glass material in such a way that no cracks or hollow spaces or the like are introduced into the material.

[0035] Preferably, the spacing is selected so as to avoid overlapping of the compressive stress zones along the planned cut surface in the central region, in which case the spacing corresponds to approximately twice the thickness of the compressive stress zones. Thus, an average spacing of 20-200 nm is particularly preferred, although smaller spacings are also possible. Modifications of the "gentle refractive index change" type are modifications with a significant change in the stress state that is non-destructive, i.e., without radial cracks, cavities or significant phase differences. In the technical literature, this type of modification is often referred to as "gentle refractive index change" due to the associated change in refractive index.

[0036] The advantage of such modifications (see USP written waveguides, USP laser welding) is that they tend to interfere less with the formation of the line focus than previous modifications.

[0037] By selecting different localized areas of the glass material for forming the line foci and by the line foci appropriately modifying the stress values ​​of the glass material within these localized areas, the extension direction and configuration of the stress zones can be precisely determined and controlled, in particular by this allowing the selection of multiple discrete locations within the glass body or glass material where the stress zones should be produced.

[0038] In this case, due to the overlap of adjacent local regions, continuous volume regions with corresponding stress values, i.e. so-called passages, are achieved in the glass body. In particular, if the formation of different stress zones, i.e. a tensile stress zone and / or two compressive stress zones, is carried out on the basis of the superposition of stress modifications of adjacent local regions, this only requires a single focus and one pass to form the different stress zones, despite the multiple stress zones. However, it is also conceivable that there are multiple foci of the linear focus per local region. Advantageously, multiple foci can be used to form the modifications, in particular in this case not all of these foci need have the same geometric shape.

[0039] To form a linear cut surface, the individual local regions may be selected such that they extend along a linear path.

[0040] In this case, the skilled person understands that the local area of ​​the glass material can essentially be larger than the area occupied in the glass material by the linear focus, the local area being defined by the fact that in the local area the glass material is modified, i.e. changed, by the linear focus with respect to its stress value.

[0041] Alternatively or additionally in a preferred embodiment, it may be envisaged that controlling the line focus includes guiding the line focus continuously or intermittently through the glass body.

[0042] Those skilled in the art know that, although a continuous formation of a line focus is not possible with a pulsed laser, the line focus formed by such a laser can be guided very well "continuously through the glass body" in the sense of the present invention, which means that the location at which the line focus is formed changes continuously.

[0043] In this case, the inventors have realized that in order to create different stress zones along the cut surface, the linear focus can be moved and / or deflected in a number of ways: for example, the linear focus can be moved (almost) continuously along the cut surface, which allows a particularly uniform modification to be achieved. In this case, the speed of the movement is preferably selected so that each stress zone can be created.

[0044] Alternatively, the linear focus reaches individual discrete positions, i.e. local regions, in sequence. In this case, these positions are preferably selected such that at least adjacent local regions, in which the respective modifications occur, at least partially overlap, as described above. For example, if the linear focus has a circular cross section and is irradiated perpendicularly to the surface, thereby forming cylindrical local regions in the glass material and representing a circular surface on the surface of the glass body corresponding to the linear focus, it is considered that in a preferred embodiment, the spacing between adjacent positions along the cut surface can be selected to be less than 1 diameter of the circle, preferably less than 1 / 2. This ensures that consistent compressive and tensile stress zones are formed in the glass material. For example, 1 diameter can be 2 μm, and 1 / 2 diameter can be 1 μm. For other linear focuses leading to other local regions and intersections with the (generally formed) surface of the glass body, the above considerations apply accordingly, and the center-to-center spacing can be replaced by the center-to-center spacing.

[0045] Alternatively or additionally, in the first and second aspects of the invention, it may be envisaged that: i. the line focus is formed by at least one light beam, in particular in the form of a laser beam, preferably at least one laser beam having an Airy beam profile and / or a Bessel beam profile, at least in the region of the line focus; ii. the light beam is formed by asymmetric light supply, at least in the region of the line focus in the form of a light beam, in particular the energy is supplied asymmetrically, preferably in such a way that (a) the center of gravity of the energy distribution in at least one plane perpendicular to the plane in which the light beam propagation takes place lies in an area of ​​the glass material that has not been modified so far, (b) the partial rays of the light beam enter only from one half of the space or only from a part of the space half, (c) the partial rays of the light beam enter only from directions selected such that the partial rays of the light beam do not propagate through an area of ​​the glass body in which the glass material has already been modified, (d) the light beam has at least one mirror image plane parallel to the plane in which the light beam propagation takes place, (e) the term "asymmetric" is to be understood in the sense of "non-rotationally symmetric", i.e. in particular without excluding other symmetries, and / or (f) the partial rays of the light beam enter only from one or two quadrants in all planes parallel to at least one surface of the glass member and / or in all planes perpendicular to the optical axis of the light beam; iii. the light beam is generated by at least one laser, the laser being operated in pulsed operation, in particular in ultrashort pulse laser operation; iv. the laser has a wavelength of 300 nm to 1200 nm, preferably 1064 nm, a pulse duration of 0.1 ps to 100 ps, ​​preferably 0.1 ps to 10 ps, ​​preferably 1 ps to 8 ps, and / or a pulse energy, at least partially in a line focus, of 10 nJ / mm to 200 μJ / mm, preferably 10 nJ / mm to 100 μJ / mm or 110 μJ / mm, for a point focus 1 nJ to 100 nJ and for a burst 1 nJ to 20 nJ; and / or v. The linear focus is formed in whole or in part by at least one phase mask, in particular having a cubic phase, at least one microscope objective lens, at least one 4f structure, at least one asymmetric beam supply means and / or a plurality of beam shaping elements, in particular cylindrical lenses, in particular the beam shaping elements being selected and / or arranged such that the linear focus is formed by coma, astigmatism and / or spherical aberration.

[0046] The inventors realized that when a laser is used to introduce stress zones into a glass body or into a glass material, and thus the light beam consists or comprises a laser beam, this can be done particularly simply and efficiently using conventional means that are commercially available. The use of one or more laser beams allows the formation of stress zones in a glass material with high precision. Moreover, optical components for laser systems are readily available. Moreover, lasers allow the formation of even the finest structures, i.e., stress zones, here.

[0047] Preferably, the laser is an ultrashort pulse laser, in particular an ultrashort pulse laser emitting pulses having a pulse length of less than 20 ps, ​​preferably 10 ps or less or 1 ps or less.

[0048] Preferably, an ultrashort pulsed laser beam with a line focus is used. If the pulse energy is appropriately selected, no cavities are created in the glass material, but the glass material is modified with respect to its stress value. This can result in the application of, for example, a tensile stress zone surrounded on each side by a compressive stress zone.

[0049] The skilled person knows that, although a continuous formation of a line focus by a pulsed laser is not possible, the line focus formed by such a laser can be "continuously moved along the cutting surface" in the sense of the present invention, which means nothing more than that in this case the location at which the line focus is formed changes continuously.

[0050] A line focus can be obtained particularly efficiently and simply if the laser beam has an Airy or Bessel beam profile. If the laser is operated in pulsed operation, it can produce modifications in the glass material particularly efficiently. Other line focuses, for example by means of a spherical aberration lens, or (for multiple passes) point focuses, for example a standard Gaussian focus, are also conceivable.

[0051] Airy beams or Bessel beams can also be generated in a particularly simple and efficient manner, i.e., for example, a Gaussian beam can be used as the starting substrate, which is then shaped into a Bessel beam by suitable optics, such as an axicon. For example, an Airy beam can be generated as an image of a beam with a cubic phase, which is formed directly by a phase mask (DOE or SLM) or by a structure with a cylindrical lens.

[0052] The pulse energy and / or pulse duration are preferably selected so as not to destroy the glass material.

[0053] Asymmetric beam delivery leads to a more stable focus of the laser beam, especially if the partial rays have optical path lengths that do not deviate too much on their way to the focus. In this case, parallelism between the refractive index change and the linear focus is important, and also symmetry, since the smallest errors in the focus occur when the optical path length change due to the refractive index change is the same for all partial rays. Asymmetric beam delivery thus leads to a precise modification of the glass material. Nevertheless, symmetric beam shapes, for example those of Bessel beams or beam shapes caused by spherical aberration optics / lenses, are also conceivable.

[0054] In this case, a person skilled in the art will understand that, although an asymmetric beam has multiple partial beams arranged asymmetrically, it is of course not the case that multiple optical paths are fundamentally used to provide an asymmetric beam.

[0055] The light beam with asymmetric beam supply fulfills the characteristic of reduced or eliminated transverse partial beams in a particularly simple and efficient manner. For this purpose, the energy is no longer supplied to the focal line rotationally symmetrically along a conical surface (e.g. via beam-forming optics), but asymmetrically. In other words, the light beam is shaped in such a way that, unlike conventionally used light beams, it does not contain any light beam components that can overlap with already produced modifications. This ensures that the light beam remains almost completely unaffected by existing modifications, and thus ensures a particularly high-quality formation of multiple stress zones, since the linear focus is formed with constant high quality over the entire thickness region of the glass element.

[0056] In connection with the beam or energy delivery, the term "asymmetric" is understood in the present invention to mean "non-rotationally symmetric", meaning that other symmetries are not excluded, for example an Airy beam has a mirror image plane parallel to the plane in which its curved extension lies.

[0057] If the energy is supplied asymmetrically and preferably configured so that the center of gravity of the energy distribution in a plane perpendicular to the light propagation direction is located in an area of ​​the glass material that has not been modified so far, the linear focus can be particularly effectively prevented from being influenced by existing modifications.

[0058] The partial beam may extend into one half of the space or into part of the space half, thereby ensuring that the partial beam always extends into a glass region that has not yet been modified.

[0059] Airy beams are particularly well suited for asymmetric / lateral beam delivery, whereas Bessel beams are particularly well suited for symmetric / radial beam delivery.

[0060] This is the case in the preferred embodiment when there is a curved focal line, which in such cases is also referred to by those skilled in the art as an "accelerated light beam".

[0061] That is, it has been found that the present invention works particularly well with a number of different beam shapes (eg, Gaussian beams, Bessel beams, spherical aberration beams, etc.) depending on the circumstances.

[0062] The ratio of beam diameter:phase mask / aberration scale is preferably chosen such that side peaks do not disturb the process.

[0063] Alternatively or additionally, in the first and second aspects of the invention, (i) in the tensile stress zone and / or in the compressive stress zone the isobars of the first principal stress extend parallel to the cutting plane; (ii) the two compressive stress zones are separated from one another, in particular extend parallel and spaced apart from one another; and / or (iii) in at least one transverse plane parallel to the surface of the glass body, preferably in all transverse planes, at least partially, preferably everywhere, i. the tensile stress zone is sandwiched, in particular directly, between the two compressive stress zones; and / or ii. the tensile stress zone has a first thickness. It may also be envisaged that the compressive stress zone has a second thickness, preferably the first or second thickness, respectively, is measured in a transverse section perpendicular to the main direction of extension of the cut surface and / or the maximum thickness of the compressive stress zone or tensile stress zone, respectively, is in said transverse section, in particular the first thickness being less than 50 μm, preferably less than 10 μm, further preferably less than 5 μm, further preferably less than 2 μm, further preferably less than 1 μm, most preferably between 0.1 μm and 1 μm, and / or the second thickness being less than 100 μm and / or more than 1 nm, in particular between 10 nm and 1 μm.

[0064] Due to the isobars of the first principal stress in the compressive stress zone and / or tensile stress zone running parallel to the planned cut surface, a particularly reliable "channelization" of the crack and thus a particularly reliable formation of the cut surface according to the desired extension direction can be achieved.

[0065] The sandwich-like surrounding of the compressive stress zone with the tensile stress zone in this way particularly ensures that the cracks run in the tensile stress zone and do not leave it, which in turn can particularly favorably support the propagation of the crack and thus the formation of the cut surface according to the desired direction of extension.

[0066] By choosing the appropriate thickness for the compressive or tensile stress zone, very good results can be achieved in terms of the cut surface with minimal modification of the glass material.

[0067] In particular, the first and second thicknesses have a preferred ratio to one another, which allows for particularly good adjustment of the extension lengths of both zone types, resulting in good control over the cut surface with minimal modification, as well as good properties of both the cut surface and the edge. Preferred values ​​for the first thickness are less than 50 μm, less than 10 μm, less than 5 μm, less than 2 μm, less than 1 μm, in particular between 0.1 μm and 1 μm. Preferred values ​​for the second thickness are less than 100 μm (or more), more than 1 nm, in particular between 10 nm and 1 μm.

[0068] In order to define as precisely as possible the location of the final cut surface, the width of the tensile stress zone or the spacing between the compressive stress zones should be minimized. In contrast, in order to obtain the most stable product possible, the thickness of the compressive stress zone should be maximized (large preload depth). Furthermore, there is an interdependence between the thickness of the compressive stress zone and its amplitude, which must be optimized (as when preloading glass).

[0069] Alternatively or additionally, in the first and second aspects of the invention, it may be envisaged that i. initial damage is induced in the glass material by a pulsed laser, preferably with a pulse energy of 80 μJ / mm to 300 μJ / mm and / or a pulse duration of 0.1 ps to 20 ps; ii. a crack is advanced by mechanical breaking, cleaving and / or at least one ultrashort pulsed laser (USP) process; and / or iii. a cut surface extends and / or is formed within a tensile stress zone and / or between two compressive stress zones.

[0070] If the initial damage is introduced into the glass material by means of a pulsed laser, the cracks can be initiated with great spatial precision and with application-optimized pulse energies.

[0071] The pulse energy for the initial damage is preferably 80 μJ / mm to 300 μJ / mm at 0.1 ps to 20 ps. If the crack is advanced by mechanical breaking, cleaving and / or at least one ultrashort pulsed laser (USP) process, this can be done by conventional reliable means that are well controlled for this purpose and are readily available.

[0072] In a preferred embodiment, alternatively or supplementarily to the first and second aspects of the invention, it may be envisaged that the cut surface extends and / or is formed within a tensile stress zone and / or between two compressive stress zones formed by the controlled line focus.

[0073] Alternatively or additionally, in the first and second aspects of the invention, it may be envisaged that the local region in the glass material extends at least partially tubular and / or cylindrical and / or curved, in particular sickle-shaped, in at least one cross-section and / or preferably extends from a surface of the glass body to an opposite surface of the glass body through the entire thickness region of the glass body enclosed between both surfaces.

[0074] In a preferred embodiment, the localized regions extend in a direction perpendicular to the main extension of the cut surface.

[0075] Alternatively or additionally, in the first and second aspects of the invention, it may be envisaged that the glass member, in particular the glass body, is at least partially and / or entirely formed in a plate shape and / or that the glass material at least partially comprises a silicate glass, such as an aluminosilicate glass and / or a borosilicate glass.

[0076] The problem is solved according to the present invention in accordance with a third aspect, in particular by proposing a glass part produced and / or producible by a method according to the first and / or second aspect of the present invention, which has at least one glass body comprising at least one glass material, the glass body having at least one side surface, and a stress value of the glass body in at least one plane at least partially, preferably entirely, corresponds to a compressive stress of preferably 1 MPa to 3000 MPa, in particular 50 MPa to 700 MPa, the plane preferably running parallel to the side surface.

[0077] The surprising finding on the basis of the present invention is thus that high strength can be achieved with respect to the side surfaces and their edges by providing a plane in the glass material, so to speak "behind" the side surfaces, in which the stress values ​​of the glass body correspond to compressive stresses.

[0078] The inventors explain this positive property by saying that compressive stresses within the glass body stabilize the sides from the inside, thus contributing to improved edge strength.

[0079] It is worth noting here that the area with compressive stress does not have to be directly on or directly behind the side, but compressive stress in a zone which, so to speak, initially occurs slightly offset inwards also leads to a significant improvement in edge strength, although it is nevertheless fundamentally advantageous if the volume near the side is also under compressive stress.

[0080] The tensile stress zone is preferably significantly wider than the compressive stress zone. The side surfaces are preferably entirely located within the compressive stress zone.

[0081] Alternatively or additionally, in the third aspect of the invention, it may be assumed that the stress values ​​at the side surface of the glass body correspond at least partially to tensile stresses, the plane is located in a volumetric region, in which the stress values ​​of the glass body correspond to compressive stresses and / or in which the isobars of the first principal stress of the glass body extend parallel to the side surface.

[0082] If, in said plane, the isobars of the first principal stress of the glass body run parallel to the sides, a particularly favorable structure is provided, which is a (intermediate) product property worth pursuing.

[0083] Alternatively or additionally, in the third aspect of the invention, it may be envisaged that the edge strength of the glass part member, in particular along the side of the glass body, is greater than 100 MPa and / or is constant across the entire side.

[0084] A maximum possible edge strength leads to glass part elements that are particularly stable and therefore easily usable.

[0085] Alternatively or additionally, in the third aspect of the invention, it may be provided that the side surface at least partially has a surface roughness, preferably an average surface roughness, with a maximum height RZ of 5 nm to 10 μm, in particular 0.1 μm to 5 μm.

[0086] Surprisingly, the low surface roughness supports the high edge strength caused by the compressive stress zones, resulting in a particularly stable and therefore better usable glass part element.

[0087] Alternatively or additionally, in the third aspect of the invention, it may be provided that the side surface is flat and / or curved and preferably has, at least partially in at least one transverse section perpendicular to the side surface, a parabolic and / or circular extension and / or an extension based on a quartic equation.

[0088] In the case of curved flanks, the forces acting on said flanks can be directed particularly advantageously, whereby the stability of the flanks and their edges can be increased. [Brief description of the drawings]

[0089] Further features and advantages of the invention will become apparent from the following description in which preferred embodiments of the invention are illustrated by way of schematic drawings. [Figure 1] FIG. 1 illustrates stress patterns for individual (discrete) modifications in a glass member. [Diagram 2] FIG. 1 shows a glass member with multiple zones of different stresses as a superposition of (discrete) modifications. [Figure 3a] FIG. 2 is a first cross-sectional view showing a ray tracing model of an Airy beam in the first cross-sectional view. [Figure 3b] FIG. 11 is a second cross-sectional view showing a ray tracing model of an Airy beam in the second cross-sectional view.

[0090] example 1 shows a plan view of a rectangular, plate-like glass member 1. The glass member 1 has a glass body 3 that contains a glass material.

[0091] Due to the formation of a line focus within the glass body 3, which extends perpendicularly to the surface (extending parallel to the drawing plane of FIG. 1) of the glass element 1, the glass material in the entire depth region (extending perpendicularly to the drawing plane of FIG. 1) is modified with respect to its stress values. This indeed results in the formation (in both cross sections parallel to the drawing plane of FIG. 1) of tensile stress zones 5 and compressive stress zones 7, in which the tensile stress zone 5 is surrounded by the compressive stress zone 7. Inside, there must be a tensile stress zone surrounded by a compressive stress zone, since at relatively high pulse energies (not taken into account here) (open) passages are formed, the walls of which are pressurized by the displaced material. However, in the present invention, no material is displaced at all.

[0092] Since the line focus has a circular cross section, the tensile stress zone 5 is also circular, and the compressive stress zone 7 is annularly and concentrically disposed so as to directly follow the tensile stress zone 5 .

[0093] In this case, in the context of the present invention, the (volume) region in the glass body 3 having compressive stress zones 7 and tensile stress zones 5 is considered to correspond to a local region according to the invention.

[0094] 2 shows a plan view of a rectangular plate-shaped glass member 11. The glass member 11 has a glass body 13 that contains a glass material.

[0095] By controlling the linear focus inside the glass body 13, at least one tensile stress zone 17 and at least two compressive stress zones 19 are formed in the glass material along a cutting surface whose extension direction is perpendicular to the drawing plane of FIG. 2 and which is to be suggested by the edge 15, where the tensile stress zones 17 are each at least partially surrounded by at least one of the two compressive stress zones 19.

[0096] In this case, controlling the line focus involves sequentially forming line foci in different localized regions of the glass material along the (planned) cut plane, thereby modifying the glass material in each of these localized regions with respect to its local stress value. For this purpose, the glass member 11 can be moved relative to the line foci, thereby sequentially forming line foci in different localized regions. In this case, the line foci generate in each localized region a stress pattern as described with reference to FIG. 1.

[0097] In this case, the spacing of the individual local regions is selected such that at least immediately adjacent local regions at least partially overlap, so that a continuous passage is formed by the modifications induced in the glass material along the (planned) cut plane. In this case, in particular, every two immediately adjacent local regions have a center-to-center spacing that is smaller than the maximum diameter of the extension of the respective local region in a cross-section parallel to the drawing plane of FIG. 2. The overlap of modifications of several local regions ultimately results in the formation of different stress zones along the (planned) cut plane. In the drawing plane of FIG. 2 and in all cross-sections parallel to the drawing plane of FIG. 2, the tensile stress zone 17 is located directly between two compressive stress zones 19 in a sandwich-like manner.

[0098] In this case, continuous passages in the form of stress zones 17, 19 in the glass body 13 can also be clearly seen in FIG.

[0099] This then results in initial damage forming a crack in the tensile stress zone 17, which can then be allowed to propagate therein, thereby cutting the glass member 11 into two glass sub-members along a (planned) cutting plane having an extension direction based on the edge 15.

[0100] It should be emphasized here that for illustrative purposes in FIG. 2 the stress zones 17, 19 are not shown formed over the entire width area, i.e. along the entire edge 15 of the glass member 11, although this is of course necessary for cutting the glass member 11.

[0101] Basically, the line focus can be the line focus of a laser beam, in which case the laser beam is formed in the form of an Airy beam.

[0102] In Fig. 3a, a first cross-section is shown, which shows a ray tracing model of an Airy beam in a first cross-section. In this case, the first cross-section extends parallel to a cut surface of an imaginary (e.g. rectangular) glass element. That is, the cut surface lies in the xz plane (for y=0) and intersects with the entire curved line focus. The line focus has its maximum intensity in Fig. 3a in the area centered at its center, i.e. the point (x=0;z=0). Corresponding to the curved line focus, the local regions extend in a similarly curved manner. In the method according to the invention, adjacent local regions according to the invention are continuous in the positive x-direction.

[0103] In Fig. 3ab, a second cross-section is shown showing a ray tracing model of an Airy beam in a second cross-section. The second cross-section lies perpendicular to the first cross-section. For example, this can be a surface of an imaginary (cuboid-shaped) glass element or a plane within the glass element extending parallel to this surface. In the method according to the invention, adjacent local regions according to the invention are continuous in the positive x-direction.

[0104] The cross section in Fig. 3b intersects with the linear focus of the laser beam in the region centered on the point (x=0; y=0). In the region of positive x values, further lateral partial beams of the laser beam are seen. As can be further seen from Fig. 3b, the Airy beam does not have any lateral components towards negative x values ​​there. Instead, in accordance with one preferred embodiment of the method according to the invention, the beam supply is asymmetric, i.e. only from the 1 / 2 spatial part with positive x values ​​in the state of Fig. 3b. As a result, if the linear focus is relatively moved in the direction of the positive x axis, no partial beams are generated in the previously modified region.

[0105] As already mentioned, in connection with the beam or energy supply, the term "asymmetric" in the present invention is understood to mean "non-rotationally symmetric", meaning that other symmetries are not excluded. For example, the described Airy beam has a mirror image plane parallel to the xz plane, as can be seen in FIG. 3b.

[0106] The features disclosed in the preceding description, in the claims and in the drawings may be of importance to various embodiments of the invention both individually and in any combination. [Explanation of symbols]

[0107] 1 Glass components 3. Glass body 5 (Tensile) Stress Zone 7. (Compressive) Stress Zone 11 Glass components 13. Vitreous body 15 (Planned) Edge 17 Stress Zones 19 Stress Zones

Claims

1. 1. A method for at least partially cutting a glass member (1, 11) along a cutting plane into at least two glass part members, comprising: - providing said glass member (1, 11) having at least one glass body (3, 13) containing at least one glass material; - controlling at least one line focus within said glass body (3, 13) such that at least one tensile stress zone (17) and at least two compressive stress zones (19) are formed in said glass material along said cut surface; - causing initial damage to form at least one crack in the glass material within the tensile stress zone (17) and / or in the glass material between the two compressive stress zones (19), respectively; and - propagating the crack in the glass material within the tensile stress zone (17) or between the two compressive stress zones (19) to form the cutting surface along which the glass member (1, 11) is cut. and (iii) controlling the line focus includes forming at least one tensile stress zone (17) and at least two compressive stress zones (19) in the glass material along the cut surface, each of the tensile stress zones (17) being at least partially surrounded by at least one of the two compressive stress zones (19).

2. (i) the compressive stress zones are at least partially spaced apart from one another; (iv) controlling the line focus includes the glass member (1, 11) being moved relative to the line focus; (v) the control of the linear focus leads to the non-destructive formation of the stress zones, resulting in a "soft index change" type of modification in the glass material, and / or the linear focus is formed sequentially along the cut surface in different localized regions of the glass material, whereby the glass material in each of the localized regions is modified with respect to its local stress value, the spacing of the individual localized regions being selected such that at least immediately adjacent localized regions at least partially overlap, whereby a continuous path is formed by the modifications induced in the glass material along the cut surface, resulting in different stress zones, and / or the individual localized regions extend along a linear path within at least one surface of the glass body (3, 13) including the cut edge of the cut surface and / or within at least one transverse cross-section of the glass member (1, 11) extending perpendicular to the optical axis of the light beam; (vi) in at least one cross-section parallel to the surface of the glass body (3, 13), the localized regions are circularly shaped and / or each two immediately adjacent localized regions (a) have a center-to-center or centroid spacing smaller than the maximum diameter of their extension in the cross-section and / or (b) have a center-to-center or centroid spacing of 1000 nm or less; (vii) - providing said glass member (1, 11) having at least one glass body (3, 13) comprising at least one glass material; - controlling at least one line focus within said glass body (3, 13) such that at least one tensile stress zone (17) and at least two compressive stress zones (19) are formed in said glass material along said cut surface; and - inducing initial damage to form at least one crack in the glass material in the tensile stress zone (17) and / or in the glass material between the two compressive stress zones (19), respectively; and then - propagating the crack in the glass material within the tensile stress zone (17) or between the two compressive stress zones (19) to form the cutting surface along which the glass member (1, 11) is cut. Including, and / or (viii) the control of the line focus proceeds without destruction in the sense of cavities, separate phases or cracks in the glass body or material; a separation is made between, on the one hand, the determination of the direction of extension of the cutting surface by the formation of a tensile stress zone, and, on the other hand, the execution of a physical cut by initiating and propagating a crack in or within the tensile stress zone; The method of claim 1.

3. i. the line focus is formed by at least one light beam in the form of a laser beam, at least one laser beam having an Airy beam profile and / or a Bessel beam profile at least in the area of ​​the line focus; ii. the light beam is formed by asymmetric light supply or energy is supplied asymmetrically, at least in the region of the line focus in the form of a light beam, so that (a) the center of gravity of the energy distribution in at least one plane perpendicular to the plane of light beam propagation is located in an area of ​​the glass material that has not been modified so far, (b) partial rays of the light beam enter from only half of the space or only a part of the space half, (c) the partial rays of the light beam pass through an area of ​​the glass body where the glass material has already been modified, (d) the light beam has at least one mirror image plane parallel to the plane through which the light beam propagates; (e) the term "asymmetric" is to be understood as meaning "non-rotationally symmetric", i.e. without excluding other symmetries; and / or (f) the light beam is incident from only one or two quadrants in all planes parallel to at least one surface of the glass member and / or in all planes perpendicular to the optical axis of the light beam; iii. the light beam is generated by at least one laser, the laser being operated in an ultrashort pulse laser operation; iv. the laser has a wavelength between 300 nm and 1200 nm, a pulse duration between 0.1 ps and 100 ps, ​​and / or a pulse energy, at least partially within the line focus, between 10 nJ / mm and 200 μJ / mm, between 1 nJ and 100 nJ for point focus and between 1 nJ and 20 nJ for bursts; and / or v. said line focus is formed in whole or in part by at least one phase mask or DOE or SLM, at least one microscope objective, at least one 4f structure, at least one asymmetric beam supply means and / or a plurality of beam shaping elements or cylindrical lenses; The method of claim 2.

4. (i) isobars of a first principal stress within the tensile stress zone (17) and / or the compressive stress zone (19) extend parallel to the cut surface; (ii) the two compressive stress zones (19) are separate from each other or extend parallel and spaced apart from each other; and / or (iii) at least partially or everywhere in at least one transverse plane parallel to a surface of the glass body (3, 13); i. the tensile stress zone (17) is sandwiched between two compressive stress zones (19); and / or ii. the tensile stress zone (17) has a first thickness and the compressive stress zone (19) has a second thickness, the first or second thickness being measured in a transverse plane perpendicular to the main direction of extension of the cut surface and / or the maximum thickness of the compressive stress zone (19) or the tensile stress zone (17), respectively, is in each of the transverse planes; 4. The method according to any one of claims 1 to 3.

5. i. a pulsed laser having a pulse energy of 80 μJ / mm to 300 μJ / mm and / or a pulse duration of 0.1 ps to 20 ps causes initial damage in the glass material; ii. the crack is propagated by mechanical breaking, cleaving and / or at least one ultrashort pulsed laser (USP) process; and / or iii. the cut surface extends and / or is formed within the tensile stress zone (17) and / or between the two compressive stress zones (19); 5. The method according to any one of claims 1 to 4.

6. 3. The method according to claim 2, wherein the localized region of the glass material extends at least partially in a tubular and / or cylindrical and / or curved manner and / or extends from a surface of the glass body (3, 13) to an opposite surface of the glass body (3, 13) through the entire thickness region of the glass body (3, 13) enclosed between both surfaces.

7. 7. The method according to claim 1, wherein the glass element (1, 11) or the glass body (3, 13) is at least partially and / or entirely formed in a plate-like shape and / or the glass material at least partially comprises a silicate glass, an aluminosilicate glass or a borosilicate glass.

8. A glass portion member, at least one glass body (3, 13) including at least one glass material, the glass body (3, 13) having at least one side surface; The stress value of the glass body (3, 13) in at least one plane corresponds at least partially or entirely to a compressive stress of 1 MPa to 3000 MPa, the plane extending parallel to the side surface, the side surface being curved or having, at least partially in at least one transverse plane perpendicular to the side surface, a parabolic or circular extension or an extension based on a quartic equation.

9. 9. The glass part according to claim 8, wherein the stress values ​​at the side surfaces of the glass body (3, 13) correspond at least partially to tensile stresses, the plane is located in a volumetric area, and in the plane the stress values ​​of the glass body (3, 13) correspond to compressive stresses and / or in the plane the isobars of the first principal stress of the glass body (3, 13) extend parallel to the side surfaces.

10. 10. The glass part according to claim 8 or 9, wherein the edge strength along the side of the glass part or of the glass body (3, 13) is greater than 100 MPa and / or is constant over the entire side.

11. The glass part member according to any one of claims 8 to 10, wherein the side surface at least partially has a surface roughness with a maximum height RZ of 5 nm to 10 μm, or an average surface roughness of 0.1 μm to 5 μm.

12. The method of claim 2, wherein (b) the center-to-center or center-of-gravity spacing is 100 nm or less, or 10 nm or less, or 1 nm or less.

13. The method of claim 3, wherein the phase mask or DOE or SLM has a cubic phase.

14. The method of claim 3, wherein the beam forming member is selected and / or positioned such that the linear focus is formed by coma, astigmatism and / or spherical aberration.

15. The method of claim 4, wherein the first thickness is less than 50 μm, or less than 10 μm, or less than 5 μm, or less than 2 μm, or less than 1 μm, or between 0.1 μm and 1 μm, and / or the second thickness is less than 100 μm and / or greater than 1 nm, or between 10 nm and 1 μm.

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