Method and 3D printing device for layer-by-layer manufacturing of objects using laser transfer

Abstract

The invention relates to a 3D printing method for layer-wise manufacturing of objects using laser transfer printing, and to a 3D printing device for carrying out the method. According to the method, a printing compound (54) applied to a carrier drum (51) is irradiated with a laser (50), separated and transferred to a substrate (27). The resulting printing compound layer is subsequently solidified and the process is repeated until the object is completely built. Using the claimed method, objects can be printed from a variety of possible printing materials at high production rates (more than 1 kg / h) without compromising the printing quality.

Description

Technical Field

[0001] This invention relates to a novel 3D printing method for producing objects layer by layer via laser transfer, and to a 3D printing apparatus for carrying out said method. The invention includes irradiating printing material applied to a carrier roller with a laser, separating it, and transferring it to a substrate. The resulting printing material layer is then cured, and this operation is repeated until the object has been fully constructed. With the method of this invention, objects made of a variety of possible printing materials can be printed at high throughput (above 1 kg / h) without compromising print quality. Background Technology

[0002] 3D printing involves building three-dimensional objects layer by layer. They are constructed under computer control from one or more liquid or solid materials according to geometry defined by CAD (Computer-Aided Design). During the construction process, physical or chemical curing or solidification processes occur. Typical materials used for 3D printing are plastics, synthetic resins, ceramics, and metals. 3D printers are used in industrial, research, and consumer applications. 3D printing is a method of additive manufacturing.

[0003] 3D printers were initially used specifically for the production of prototypes and models, as well as for the production of objects for which only a few examples are needed. Of increasing importance are personalized geometries in medicine and sports, and objects that simply cannot be produced by other methods. One example is an object with an internal mesh structure.

[0004] 3D printing offers advantages over injection molding: it eliminates the need for complex production processes involving molds and models. 3D printing also surpasses all material removal methods, such as those involving material removal processes (e.g., turning, drilling, grinding, milling), meaning it eliminates the need to process the blank and results in virtually no material loss.

[0005] Additive manufacturing methods (3D printing) encompass a variety of techniques for the automated additive construction of features by allocating layers to a shaped article (A) (A. Gebhardt, Generative Fertigungsverfahren [Additive Manufacturing Methods], Carl Hanser Verlag, Munich 2013). A prerequisite for all additive manufacturing methods is the generation of the desired geometry and any additional properties (e.g., color, material composition) of the shaped article in the form of a digital 3D dataset, which can be considered a virtual model of the shaped article. This modeling is preferably achieved through various 3D-CAD construction methods (computer-aided design). The input data used to generate the 3D-CAD model can also be, for example, 3D measurement data generated by CT (computed tomography) or MRT (magnetic resonance tomography). Subsequently, the 3D-CAD dataset must be supplemented with material-specific data, method-specific data, and system-specific data, which is achieved by transferring this data to additive manufacturing software via an interface in an appropriate format (e.g., STL, CLI / SLC, PLY, VRML, AMF formats). Taking into account the optimal orientation of components in the build space, support structure, etc., the software ultimately uses geometric information to generate virtual slices. The complete dataset ultimately allows for direct addressing of machines (3D printers) used in additive manufacturing.

[0006] For example, the software program is as follows:

[0007] 1. Construction of components in CAD format

[0008] 2. Output of STL data format

[0009] 3. Divide the 3D model into slices parallel to the printing plane and generate GCode.

[0010] 4. Transmission of G-Code to the Printer Controller

[0011] Additive manufacturing methods can be used with a variety of materials and combinations thereof (e.g., metals, plastics, ceramics, glass). For example, for the additive manufacturing of objects, there are already several established methods, such as...

[0012] - Fused deposition modeling (FDM) for plastics and certain synthetic resins

[0013] - Stereopolymerization molding for liquid synthetic resins

[0014] Laser sintering of metals, polymers and ceramics

[0015] - Electron beam melting for metals

[0016] Also known are methods in which the printed material is deposited by droplet dosage (i.e., jetting) or continuous extrusion (in the so-called dispensing or extrusion method), and subsequently cured, for example by the action of UV radiation or in some other way.

[0017] Standard 3D printing methods are described in, for example, WO2006020685 A2, WO2013091003 A1, WO2015059502A1 and WO2016071241A1.

[0018] To date, none of the known 3D printing methods are suitable for producing precision objects in high volumes. Specific drawbacks include the low throughput of individual technologies (far below 1 kg / h) and limitations regarding possible printing materials, particularly their chemical and physical properties (e.g., limitations on type, viscosity, filler content, and solvent content).

[0019] To date, there is no known 3D printing method that is precise enough to produce objects at a rate greater than 1 kg / h and is suitable for a variety of printing materials (object forming materials or support materials).

[0020] CN 110666169 A discloses a 3D printing apparatus that produces 3D objects in batch operations via a laser transfer method. This involves applying metal as a 3D printing material to separate carriers in independent processes via magnetron sputtering, and manually clamping them in a laser and a moving device. Continuous printing is not possible here. Summary of the Invention

[0021] Therefore, the object of this invention is to provide an additive 3D printing method that results in high-quality printing with minimal printing time and high productivity. A particular objective is to ensure that the printing material is positioned at the intended target location without trajectory errors. Furthermore, this method is applicable to a variety of different printing materials.

[0022] This objective has been unexpectedly achieved through the method and apparatus of this invention. This invention enables the printing of objects at a high throughput greater than 1 kg / h without compromising print quality. Attached Figure Description

[0023] Figure 1 A process diagram of a composite manufacturing equipment system for producing 3D printed products is shown.

[0024] Figure 2 A structural diagram of the 3D printing unit is shown.

[0025] Figure 3 A structural diagram of the inspection unit is shown.

[0026] Figure 4 A structural diagram of the post-processing unit is shown.

[0027] Figure 5 A diagram of the LIFT-3D printing module shows the separation operation and positioning using printing material.

[0028] Figure 6 The process of processing printing materials for the LIFT-3D printing module is shown. Detailed Implementation

[0029] This invention relates to a method for producing objects layer by layer by laser transfer in a 3D printing apparatus, the 3D printing apparatus comprising at least one plate (28), at least one laser source (50), and at least one carrier roller (51); wherein the material of the carrier roller (51) is transparent to a laser beam (50a) from the laser source (50), and wherein the method comprises the following steps:

[0030] (a) Coating at least a portion of the outer surface of the carrier roller (51) with at least one printing material (54);

[0031] (b) Irradiating the carrier roller (51) with a laser beam (50a) from the laser source (50) such that at least a portion of the applied printing material (54) is separated from the carrier roller (51) and transferred to the plate (28), to an external component (7) positioned thereon, or to a previously applied layer of printing material; wherein the irradiation is achieved in the following manner

[0032] (i) A laser beam (50a) passes through the outside of the carrier roller (51) and directly impacts the printing material (54), or

[0033] (ii) A laser beam (50a) strikes the printing material (54) via one or more mirrors within a carrier roller (51).

[0034] (c) A printing material layer is formed by curing the printing material (54) transferred in step (b).

[0035] (d) Repeat steps (a) through (c) until the object has been fully constructed.

[0036] The present invention further relates to a 3D printing apparatus for producing objects by laser transfer, the 3D printing apparatus comprising:

[0037] - At least one laser source (50);

[0038] - At least one carrier roller (51), wherein the material of the carrier roller (51) is transparent to the laser beam (50a) from the laser source (50),

[0039] - At least one application system (52) configured to coat at least a portion of the outer surface of the carrier roller (51) with at least one printing material (54);

[0040] -At least one plate (28),

[0041] The laser source (50) is configured to irradiate the carrier roller (51) such that at least a portion of the printing material (54) applied to the carrier roller (51) is separated and transferred to the plate (28), the external component (7) thereon, or a previously applied layer of printing material.

[0042] The 3D printing equipment is configured such that the laser beam (50a)

[0043] (i) The printing material (54) is directly impacted from the outside of the carrier roller (51) through the carrier roller (51), or

[0044] (ii) The printing material (54) is struck by one or more mirrors within the carrier roller (51).

[0045] Since the method of the present invention for producing objects layer by layer is preferably implemented by the 3D printing apparatus of the present invention, the following description should be understood such that features described in the context of the method are disclosed equivalently to the 3D printing apparatus, and conversely, features described in the context of the 3D printing apparatus are disclosed equivalently to the method.

[0046] The standard laser transfer printing method (LIFT = Laser Induced Forward Transfer) is well described in the literature and forms part of the prior art. For example, a specific application is described in WO 2020156632 A1.

[0047] The plate (28) is preferably arranged below the carrier roller (51).

[0048] In one embodiment, the printing module (20), including the carrier roller (51), remains fixed during printing, while the plate (28) is configured to be movable. However, this arrangement is less preferred due to the lower stability and dynamic impact on the printed body. The carrier roller itself remains rotatable in this arrangement, even though the printing module as a whole remains fixed.

[0049] Precise local positioning of the printing material is preferably achieved by plate (28) in the Z direction (corresponding to Figure 5 On the upper / lower axis and in the Y direction (corresponding to the upper / lower axis) and the Y direction Figure 5 The movement of the laser source (50) along the left / right axis and in the X direction (corresponding to the left / right axis) and the movement of the laser source (50) in the X direction (corresponding to the left / right axis) Figure 5It is achieved by deflection on the backward / forward axis.

[0050] In an alternative embodiment, the board (28) remains fixed, while the printing module is configured to be movable.

[0051] The accurate local positioning of the printing material is preferably achieved by the movement of the printing module (20) in the Z and Y directions and the deflection of the laser source (50) in the X direction.

[0052] In a particularly preferred embodiment, the printing module (20) including the carrier roller (51) and the plate (28) is configured to be movable in one or more directions (X, Y and / or Z).

[0053] Accurate local positioning of the printing material is preferably achieved by moving the plate (28) in the Z direction, moving the printing module (20) in the Y direction, and deflecting the laser source (50) in the X direction. This arrangement is the easiest to implement technically and is therefore superior to other arrangements.

[0054] Furthermore, hybrid variations of the described arrangement are also possible, wherein one or more components are configured to be movable in one or more directions (X, Y and / or Z) and one or more components are optionally configured to be fixed.

[0055] Location data is transmitted to the positioning and deflection system via the entire controller (14).

[0056] The laser source is preferably positioned above the carrier roller (51) so that the laser beam (50a) can be directly guided through the two walls of the carrier roller (51) onto the printing material applied to the underside of the carrier roller.

[0057] Alternatively, the laser source (50) may be located anywhere (inside or outside) relative to the carrier roller. In this case, the laser beam is preferably guided onto the printing material applied to the carrier roller through one or more mirrors within the carrier roller via only one wall.

[0058] These mirrors can be configured to be movable or rigid, preferably movable. Movable mirrors have the advantage that they can variably guide the laser beam to a specific area of ​​the printing material. In a particular embodiment, at least one movable mirror is present within the carrier cylinder.

[0059] The carrier roller (51) preferably has an outer diameter in the range of 50 mm to 300 mm, more preferably in the range of 70 mm to 150 mm, and especially preferably in the range of 80 mm to 120 mm.

[0060] The carrier roller (51) can have a compact or hollow configuration. The carrier roller (51) preferably has a hollow configuration. In this case, the carrier roller (51) preferably has a wall thickness in the range of 1 mm to 20 mm, more preferably in the range of 3 mm to 15 mm, and especially preferably in the range of 6 mm to 12 mm.

[0061] The length of the carrier roller (51) is preferably 20 mm to 600 mm, more preferably 100 mm to 400 mm, and particularly preferably 150 mm to 300 mm.

[0062] The tolerance range for the geometric dimension variation of the carrier roller (51) is preferably less than 500 μm, more preferably less than 100 μm, and especially preferably less than 10 μm.

[0063] The surface roughness (Ra) of the carrier cylinder (51) is preferably less than 10 μm, more preferably less than 100 nm, and is measured by a confocal laser scanning microscope (e.g., a VK-X1000 from Keyence).

[0064] These surfaces are preferably polished and may optionally be equipped with an anti-reflective coating.

[0065] The printing material layer (54) coated onto the carrier roller (51) preferably has a layer thickness of 1 μm to 1000 μm, more preferably 10 μm to 500 μm, and particularly preferably 50 μm to 150 μm.

[0066] The distance h between the coated carrier roller (51) and the plate (28) (see [reference]) Figure 5 Preferably, it is in the range of 20μm to 600μm, more preferably 80μm to 400μm, and especially preferably 100μm to 200μm.

[0067] In many known implementations of the LIFT method, the reference laser beam is focused at the interface between the printing material and the carrier system. In implementations using silicone compositions, a better printed image is produced when the laser focus (50b) is located within the carrier roller and above the interface between the printing material and the carrier roller. The focus here ranges from a few micrometers to a few millimeters above the carrier roller / printing material interface. Focusing the laser beam onto, within, or below the interface initially causes separation, but this subsequently results in significant post-heating on the target surface and may lead to combustion or thermal degradation of the applied printing material (58).

[0068] The focal point of the laser beam is preferably selected such that it is within the range of 0.01 mm to 10 mm above the interface between the printing material and the carrier roller, preferably 0.1 mm to 5 mm, and particularly preferably 1 mm to 3 mm.

[0069] Standard laser sources are, for example, Nd:YAG lasers (neodymium-doped yttrium aluminum garnet lasers) that emit laser radiation in the NIR (near-infrared) region. These wavelengths are used in most laser systems coupled to opaque media. An advantage here is the use of a carrier material (such as glass or quartz glass) for the carrier roller. A disadvantage is the need to add absorbers, such as carbon black, graphite, or CNTs, to the transparent silicone elastomer. Non-conductive absorbers are commercially available, for example, from FEW Chemicals GmbH, Germany.

[0070] In a particular implementation, irradiation with a laser is achieved in the MIR (mid-infrared region). A suitable laser source is in the wavelength range of 8-12 μm, preferably 10.6 μm (CO2 laser). In this particular configuration, a transparent silicone elastomer and a variable support material can be used without the addition of an absorbent. However, technically, the carrier roller should be implemented to be optically transparent to the corresponding wavelength. ZnSe glass (zinc selenide) with a wavelength of 10.6 μm is preferred. An antireflective coating is particularly preferred at the interface. These are available, for example, from LASER COMPONENTS GmbH, Germany.

[0071] The carrier roller is preferably made of glass, quartz glass, polyethylene terephthalate, polycarbonate, polyimide, polymethyl methacrylate (PMMA), ZnSe, ZnS, BaF2, CaF2, Ge, KBr, NaCl, MgF2, LiF and Si.

[0072] However, silicon is particularly preferred as the material for the carrier roller. Especially preferred is ultrapure silicon in single-crystal form, preferably having a defined lattice arrangement. Particularly preferred is silicon with a resistivity greater than 1000 ohms*cm produced by the zone melting method (floating zone method). Such ultrapure silicon is available, for example, from Wacker Chemie AG, Germany. Single-crystal silicon is available, for example, from Siltronic AG, Germany.

[0073] The curing mode should be selected according to the printing material. Curing is preferably achieved by supplying heat, electromagnetic radiation, and / or moisture. Curing by electromagnetic radiation (e.g., IR, UV, and / or UV-VIS radiation) is particularly preferred, especially when using silicone compositions. In the case of thermoplastics as printing materials, curing by cooling is also possible.

[0074] The 3D printing equipment preferably includes at least one curing module configured to cure the printing material.

[0075] The printing material can also be cured by a laser beam from a laser source.

[0076] Different curing strategies can also be selected, such as curing the initial portion of the printed material to allow for subsequent modifications.

[0077] Different printing materials can also be cured using different methods.

[0078] In another embodiment, while the uncured printing material is being cured, the printed body is mechanically stretched or compressed after printing.

[0079] Before and / or during curing, voltage may be additionally applied to the part, in which case electrical contact is achieved through areas of uncured printed material, and curing is performed after the curing process is applied.

[0080] Modification methods and examples involving field and mechanical deformation in the production of ferroelectric polyvinylidene fluoride (PDF) films are known to those skilled in the art.

[0081] Curing can also be performed using high-energy radiation, such as electron beams or cobalt-60 radiation. Many electron beam curing methods are known in the prior art.

[0082] In a preferred embodiment, a continuous belt (9) is in a movable arrangement on the plate. In step (b), printing material is then transferred to the belt (9), to an external component (7) positioned on the belt (9), or to a pre-applied layer of printing material (58). The belt (9) enables the introduction and discharge of these different modules of the 3D printing apparatus (e.g., printing modules, curing modules, inspection units, etc.).

[0083] The 3D printing equipment preferably includes at least one belt feeder (10) and a belt storage device (18) for the drive belt (9).

[0084] In another embodiment, the 3D printing apparatus includes at least one pick-and-place unit (8) and / or removal unit (13) configured to position external components (7) and / or prints (12) on and / or remove them from the plate (28) or the conveyor belt (9).

[0085] As an alternative to the continuous method via a conveyor belt, this method can also be performed in batches. This involves manually positioning or removing the printed parts.

[0086] Especially when used with silicone compositions, it has been found advantageous to have a defined charge and an extension with an additional applied electrostatic field (EFLIFT = Electric Field Laser-Induced Forward Transfer). What is achieved here is improved separation and positioning with additional charge on the printing material and the target surface. EFLIFT is described, for example, in WO 2020156632 A1.

[0087] Therefore, prior to step (b), it is particularly preferred to charge the printing material applied to the carrier roller to potential phi_1 and the plate to potential phi_3, wherein phi_1 and phi_3 have opposite polarities. Symbols will be used hereinafter. Instead of phi.

[0088] In another embodiment, the surfaces of the external components, the previously applied layer of printing material, and / or any drive belt are additionally charged to a potential phi_2, wherein phi_2 and phi_1 have opposite polarities, and phi_2 is selected such that at least a portion of the charge on the printing material transferred in step (b) is neutralized on the surface to be printed.

[0089] The plate is preferably a movable vacuum plate, which fixes the drive belt at a specific distance from the coated carrier cylinder in step (b).

[0090] Preferably, before step (b) and, if appropriate, before charging to potential phi_2 or phi_3, the surface of the external part to be printed and / or the previously applied printing material layer of the board or conveyor belt is electrostatically discharged by a pre-discharge module.

[0091] Therefore, the 3D printing equipment preferably includes at least one charging / discharging module configured to independently charge the printing material applied to the carrier roller, the surface of the plate, and / or the target surface to be printed (e.g., a drive belt) to a specific potential phi.

[0092] In the context of this invention, the term "charging" should be understood as referring to increasing or decreasing electrical potential. This also includes charging or discharging to a potential of 0V.

[0093] For example, a corresponding ionization system is described in WO 2018072809 A1, particularly for silicone compositions.

[0094] The carrier roller is preferably rotated, wherein in step (a) a layer comprising printing material is applied to the rotating carrier roller by an application system, and in step (b) printing material that has not been separated from the rotating carrier roller is removed by a removal system.

[0095] The 3D printing equipment preferably includes at least one removal system configured to remove printing material that has not been separated from the carrier roller (51).

[0096] Systems for applying and removing rollers are known to those skilled in the art in the fields of offset and gravure printing. These systems are commercially available, for example, from Heidelberger Druckmaschinen AG in Germany.

[0097] In an alternative embodiment, the carrier roller is coated manually, but automatic coating is preferred.

[0098] In a particular embodiment of the 3D printing apparatus, the carrier roller (51), the application system (52), the removal system (53), and / or the build space of the 3D printing apparatus are configured to be heatable and / or coolable.

[0099] Preferably, the printing material removed by the removal system (53) is reused in step (a) for coating the carrier roller.

[0100] Preferably, the printing material removed by the removal system (53) is processed by at least one processing unit (64) before being reused, wherein the processing operation includes one or more of the following steps: crushing, filtering, degassing, wetting, demolding, adding additives, and measuring the physical and / or chemical properties of the printing material.

[0101] Therefore, the 3D printing equipment preferably includes at least one processing unit (64) configured to process the printing material (54) removed by the removal system (53) for reuse.

[0102] If the printing material comprises two or more components, it is preferable to supply each component from the metering unit (61, 62) to one or more mixing systems (63, 57) prior to step (a).

[0103] The printing material 54 removed by the removal system 53 is preferably mixed into the mixing systems 63, 67.

[0104] The type and composition of printing materials are not subject to any specific restrictions.

[0105] The printing material preferably contains less than 5% by weight of the total mass of the printing material, more preferably less than 1% by weight, particularly preferably less than 0.5% by weight, and most preferably less than 0.1% by weight.

[0106] Suitable solvents are known in the prior art and are commercially available. The solvent should be selected based on the chemical composition of the printing material. The solvent can be, for example, water or an aqueous solution. Alternatively, the solvent can be, for example, an organic solvent. Organic solvents having 3 to 20 carbon atoms are preferred. Examples of solvents include aliphatic hydrocarbons, such as nonane, naphthane, and dodecane; aromatic hydrocarbons, such as mesitylene, xylene, and toluene; esters, such as ethyl acetate and butyrolactone; ethers, such as n-butyl ether and polyethylene glycol monomethyl ester; ketones, such as methyl isobutyl ketone and methyl pentyl ketone; and combinations of the above solvents.

[0107] Suitable printing materials include, for example, one or more of the following materials that form objects: silicone, polyacrylate, polyolefin, polyurethane, polyurea, polyacrylonitrile, polyester, polyether, polylactic acid, polyhydroxyalkanoates, and mixtures, solutions, dispersions, or copolymers comprising one or more of the above-mentioned materials that form objects. Silicone compositions are preferred.

[0108] Particularly preferred are at least one printing material selected from the group consisting of crosslinkable silicone elastomer compositions, silicone gels, silicone resins, silicone oils, and silicone dispersions.

[0109] In addition, one or more support materials can be used as printing materials, which are then removed after the object is constructed.

[0110] The material used to form the printed object can, in principle, be any silicone composition known in the prior art. A silicone composition is preferably chosen such that its cross-linking is not triggered solely by irradiation with a laser used in laser transfer printing.

[0111] For example, addition-crosslinked, peroxidation-crosslinked, condensation-crosslinked, or radiation-crosslinked silicone elastomer compositions can be used. Peroxidation-crosslinked compositions or addition-crosslinked compositions are preferred. Addition-crosslinked compositions are particularly preferred.

[0112] Silicone elastomer compositions can be formulated as one-component or two-component forms. The silicone elastomer compositions are crosslinked by supplying heat, UV light, and / or moisture. Suitable examples include the following silicone elastomer compositions: HTV (addition crosslinking), HTV (radiation crosslinking), LSR, RTV 2 (addition crosslinking), RTV 2 (condensation crosslinking), RTV 1, TPSE (thermoplastic silicone elastomer), thiol-olefin, and cyanoacetamide-crosslinking systems.

[0113] In its simplest case, the addition-crosslinked silicone composition comprises:

[0114] (A) At least one straight-chain compound having a group containing an aliphatic carbon-carbon double bond,

[0115] (B) At least one linear organopolysiloxane compound having Si-bonded hydrogen atoms,

[0116] Alternatively, in place of (A) and (B) or in addition to (A) and (B),

[0117] (C) At least one linear organopolysiloxane compound having Si-C bonded groups, the linear organopolysiloxane compound having aliphatic carbon-carbon double bonds and Si-bonded hydrogen atoms, and

[0118] (D) At least one hydrogenation silanization catalyst.

[0119] In specific embodiments, these silicone compositions are silicone elastomer compositions having fluorinated side groups, such as those described, for example, in WO 28177523 A1. In this embodiment, components (A), (B), and / or (C) preferably contain at least 2.5 mol%, more preferably at least 5 mol%, of fluorinated side groups, such as 3,3,3-trifluoropropylmethylsiloxy and / or bis(3,3,3-trifluoropropyl)siloxy groups.

[0120] The silicone composition can be a one-component silicone composition or a two-component silicone composition. In the latter case, the two components of the composition can contain any combination of any components, typically provided that one component does not simultaneously contain a siloxane having aliphatic multiple bonds, a siloxane having Si-bonded hydrogen, and a catalyst, i.e., substantially not simultaneously contain components (A), (B), and (D) or (C) and (D).

[0121] As is well known, the choice of compounds (A) and (B) or (C) used in the composition enables crosslinking. For example, compound (A) has at least two aliphatic unsaturated groups and (B) has at least three Si-bonded hydrogen atoms, or compound (A) has at least three aliphatic unsaturated groups and siloxane (B) has at least two Si-bonded hydrogen atoms, or, instead of compounds (A) and (B), siloxane (C) having aliphatic unsaturated groups and Si-bonded hydrogen atoms in the aforementioned ratio is used. Similarly, it is a mixture of (A) and (B) and (C) with the aforementioned ratio of aliphatic unsaturated groups and Si-bonded hydrogen atoms.

[0122] The compound (A) used may be a silicon-free organic compound preferably having at least two aliphatic unsaturated groups, and an organosilicon compound preferably having at least two aliphatic unsaturated groups, or a mixture thereof.

[0123] Examples of silicone-free organosilicone compounds (A) include 1,3,5-trivinylcyclohexane, 2,3-dimethyl-1,3-butadiene, 7-methyl-3-methylene-1,6-octadiene, 2-methyl-1,3-butadiene, 1,5-hexadiene, 1,7-octadiene, 4,7-methylene-4,7,8,9-tetrahydroindene, methylcyclopentadiene, 5-vinyl-2-norbornene, bicyclo[2.2.1]hepta-2,5-diene, 1,3-diisopropenylbenzene, vinyl-containing polybutadiene, 1,4-divinylcyclohexane, 1,3,5-trienylbenzene, 1,3,5-trivinylbenzene, 1,2,4-trivinylcyclohexane, 1,3,5-triisopropenylbenzene, 1,4-divinylbenzene, 3-methyl-1,5-heptadiene, 3 -Phenyl-1,5-hexadiene, 3-vinyl-1,5-hexadiene and 4,5-dimethyl-4,5-diethyl-1,7-octadiene, N,N'-methylenebisacrylamide, 1,1,1-tris(hydroxymethyl)propane triacrylate, 1,1,1-tris(hydroxymethyl)propane trimethacrylate, tripropylene glycol diacrylate, diallyl ether, diallylamine, diallyl carbonate, N,N'-diallylurea, triallylamine, tris(2-methylallyl)amine, 2,4,6-triallyloxy-1,3,5-triazine, triallyl-s-triazine-2,4,6(1H,3H,5H)-trione, diallyl malonate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, poly(propylene glycol) methacrylate.

[0124] The silicone composition preferably comprises at least one aliphatic unsaturated organosilicon as component (A), wherein any aliphatic unsaturated organosilicon compound used to date can be used as the addition crosslinking compound, such as silicone block copolymers having urea segments, silicone block copolymers having amide segments and / or imide segments and / or ester-amide segments and / or polystyrene segments and / or silanthracene segments and / or carborane segments, and silicone graft copolymers having ether groups.

[0125] The organosilicon compound (A) used, which has Si-C-bonded groups and aliphatic carbon-carbon multiple bonds, is preferably a straight-chain or branched organopolysiloxane formed from units of general formula (I).

[0126] R 4 a R 5 b SiO (4-a-b) / 2 (I)

[0127] in

[0128] R 4 They are the same or different and are independently organic or inorganic groups that do not contain aliphatic carbon-carbon double bonds.

[0129] R 5 They are identical or different and independently substituted or unsubstituted Si-C-bonded hydrocarbon groups having at least one aliphatic carbon-carbon multiple bond with a single valence.

[0130] a = 0, 1, 2 or 3, and

[0131] b = 0, 1, or 2

[0132] The condition is that the sum of a+b is less than or equal to 3, and each molecule contains at least 2 R's. 5 Group.

[0133] R 4 The groups can be monovalent or polyvalent, wherein these polyvalent groups, such as divalent, trivalent and tetravalent groups, can then connect multiple, such as two, three or four siloxy units of formula (I) to each other.

[0134] R 4 Other embodiments include monovalent groups -F, -Cl, -Br, -OR. 6 -CN, -SCN, -NCO, and substituted or unsubstituted hydrocarbon groups that can be interleaved by oxygen atoms or -C(O)- groups, and divalent groups bonded to either end by Si according to formula (I). If R 4 If the group includes a SiC-bonded substituted hydrocarbon group, the preferred substituents are halogen atoms, phosphorus-containing groups, cyano groups, and -OR groups. 6 -NR 6 -、-NR 6 2. -NR 6 -C(O)-NR 6 2. -C(O)-NR 6 2. -C(O)R 6 -C(O)OR 6 -SO2-Ph and -C6F5. R 6 Independently, they are the same or different and are either hydrogen atoms or monovalent hydrocarbon groups having 1 to 20 carbon atoms, and Ph is a phenyl group.

[0135] R 4Examples of groups include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl groups; hexyl groups such as n-hexyl groups; heptyl groups such as n-heptyl groups; octyl groups such as n-octyl groups; and isooctyl groups such as 2,2,4-trimethylpentyl groups; nonyl groups such as n-nonyl groups; decyl groups such as n-decyl groups; dodecyl groups such as n-dodecyl groups; and octadecyl groups such as n-octadecyl groups; cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and methylcyclohexyl groups; aryl groups such as phenyl, naphthyl, anthracene, and phenanthrene groups; alkylaryl groups such as o-, m-, and p-tolyl groups; xylyl groups and ethylphenyl groups; and aralkyl groups such as benzyl groups, α- and β-phenylethyl groups.

[0136] Replacement R 4 Examples of functional groups include haloalkyl groups, such as 3,3,3-trifluoro-n-propyl groups, 2,2,2,2',2',2'-hexafluoroisopropyl groups, heptafluoroisopropyl groups, haloaryl groups, such as ortho, meta, and para-chlorophenyl groups, and -(CH2)-N(R) groups. 6 )C(O)NR 6 2,-(CH2) n -C(O)NR 6 2,-(CH2) o -C(O)R 6 ,-(CH2) o -C(O)OR 6 ,-(CH2) o -C(O)NR 6 2, -(CH2)-C(O)-(CH2) p C(O)CH3, -(CH2)-O-CO-R 6 -(CH2)-NR 6 -(CH2) p -NR 6 2,-(CH2) o -O-(CH2) p CH(OH)CH2OH,-(CH2) o (OCH2CH2) p OR 6 ,-(CH2) o -SO2-Ph and -(CH2) o -O-C6F5, where R 6 Ph conforms to the definition given above, and o and p are the same or different integers from 0 to 10.

[0137] R, as a divalent group Si-bonded at either end according to formula (I) 4The embodiments are derived from the above for R 4 Examples of the given monovalent groups, wherein additional bonds exist through the substitution of hydrogen atoms; examples of such groups are -(CH2)-, -CH(CH3)-, -C(CH3)2-, -CH(CH3)-CH2-, -C6H4-, -CH(Ph)-CH2-, -C(CF3)2-, -(CH2)-. o -C6H4-(CH2) o -,-(CH2) o -C6H4-C6H4-(CH2) o -,-(CH2O) p (CH2CH2O) o ,-(CH2) o -O x -C6H4-SO2-C6H4-O x -(CH2) o - where x is 0 or 1, and Ph, o, and p have the definitions given above.

[0138] R 4 The group is preferably a monovalent SiC-bonded, optionally substituted hydrocarbon group that does not contain aliphatic carbon-carbon multiple bonds and has 1 to 18 carbon atoms, more preferably a monovalent SiC-bonded hydrocarbon group that does not contain aliphatic carbon-carbon multiple bonds and has 1 to 6 carbon atoms, especially a methyl or phenyl group.

[0139] R from equation (I) 5 The functional group may include any group that is readily capable of undergoing an addition reaction (hydrosilanization) with SiH functional compounds.

[0140] If R 5 The groups include SiC-bonded substituted hydrocarbon groups, with preferred substituents being halogen atoms, cyano groups, and -OR groups. 6 , where R 6 It has the definitions given above.

[0141] R 5 The groups preferably include alkenyl and ynyl groups having 2 to 16 carbon atoms, such as vinyl, allyl, methylallyl, 1-propenyl, 5-hexenyl, ethynyl, butadienyl, hexadienyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, vinylcyclohexylethyl, divinylcyclohexylethyl, norbornenyl, vinylphenyl, and styryl groups, with vinyl, allyl, and hexenyl groups being particularly preferred.

[0142] The molecular weight of component (A) can vary over a wide range, for example, in the range of 10. 2 Up to 10 6Between g / mol. For example, component (A) can be an alkenyl-functionalized oligomeric siloxane with a relatively low molecular weight, such as 1,2-divinyltetramethyldisiloxane, but it can also be a highly polymeric polydimethylsiloxane with Si-bonded vinyl groups at chain or terminal positions, for example, having 10 g / mol. 5 The molecular weight is measured in g / mol (number mean determined by NMR). The molecular structure of the forming component (A) is not fixed; more specifically, the structure of higher molecular weight (i.e., oligomers or polymers) siloxanes can be linear, cyclic, branched, or resinous and network-like. Linear and cyclic polysiloxanes are preferably formed by formula R. 4 3SiO 1 / 2 R 5 R 4 2SiO 1 / 2 R 5 R 4 SiO 1 / 2 and R 4 2SiO 2 / 2 The unit composition, where R 4 and R 5 With the definitions given above, branched and network polysiloxanes further contain trifunctional and / or tetrafunctional units, preferably R. 4 SiO 3 / 2 R 5 SiO 3 / 2 and SiO 4 / 2 Those. Of course, a mixture of different siloxanes that meet the criteria of component (A) can also be used.

[0143] As component (A), a vinyl-functional, substantially linear polydiorganosiloxane is particularly preferred, having a viscosity of 0.01 to 500,000 Pa·s, more preferably 0.1 to 100,000 Pa·s, measured in each case at 25°C by means of a rheometer calibrated with a cone-plate system CP50-2 having an opening angle of 2° and a viscosity of 1s. -1 The shear rate.

[0144] The organosilicon compound (B) used can be any hydrogen-functional organosilicon compound that has been used to date in addition-crosslinkable compositions.

[0145] The organopolysiloxane (B) used, having Si-bonded atoms, is preferably a linear, cyclic, or branched organopolysiloxane composed of units of general formula (III).

[0146] R 4 c Hd SiO (4-c-d) / 2 (III)

[0147] in

[0148] R 4 Based on the definitions given above,

[0149] c is 0, 1, 2, or 3, and

[0150] d is 0, 1, or 2.

[0151] The conditions are that the sum of c+d is no greater than 3 and each molecule has at least two Si-bonded hydrogen atoms.

[0152] Based on the total weight of the organopolysiloxane (B), the organopolysiloxane (B) used preferably contains 0.04 to 1.7% Si-bonded hydrogen by weight.

[0153] The molecular weight of component (B) can also vary over a wide range, for example, in the range of 10. 2 With 10 6 Between g / mol. For example, component (B) can be a relatively low molecular weight SiH-functional oligomeric siloxane, such as tetramethyldisiloxane, but it can also be a highly polymeric polydimethylsiloxane or a silicone resin having SiH groups at the chain or terminal position.

[0154] The molecular structure of component (B) is not fixed; more specifically, the structure of higher molecular weight (i.e., oligomerized or polymerized) SiH-containing siloxanes can be linear, cyclic, branched, or resinous and network-like. Linear and cyclic polysiloxanes (B) are preferably formed from formula R. 4 3SiO 1 / 2 HR 4 2SiO 1 / 2 HR 4 SiO 2 / 2 and R 4 2SiO 2 / 2 The unit composition, where R 4 With the definitions given above, branched and network polysiloxanes further contain trifunctional and / or tetrafunctional units, preferably R. 4 SiO 3 / 2 HSiO 3 / 2 and SiO 4 / 2 Of those, R 4 It has the definitions given above.

[0155] Of course, mixtures of different siloxanes that meet the criteria for component (B) can also be used. In particular, in addition to the required SiH groups, the molecules forming component (B) may optionally also contain aliphatic unsaturated groups. Particularly preferred are SiH-functionalized compounds with low molecular weights, such as tetra(dimethylsiloxy)silane and tetramethylcyclotetrasiloxane, as well as SiH-containing siloxanes with higher molecular weights, such as poly(hydromethyl)siloxane and poly(dimethylhydromethyl)siloxane, which have a viscosity of 10 to 20,000 mPa·s at 25°C, measured according to DIN EN ISO 3219:1994 and DIN 53019 by means of a rheometer calibrated with a cone-plate system, having an opening angle of 2° and a viscosity of 1 s. -1 The shear rate of CP50-2 cones, or similar SiH-containing compounds in which some of the methyl groups have been replaced by 3,3,3-trifluoropropyl or phenyl groups.

[0156] Component (B) is preferably present in the crosslinkable silicone composition in an amount such that the molar ratio of SiH groups from (A) to aliphatic unsaturated groups is 0.1 to 20, more preferably 0.3 to 2.0.

[0157] The components (A) and (B) used are commercial products or can be produced by standard methods.

[0158] The silicone composition may contain an organopolysiloxane (C) instead of components (A) and (B), said organopolysiloxane (C) containing both aliphatic carbon-carbon multiple bonds and Si-bonded hydrogen atoms. The silicone composition may also contain all three components (A), (B), and (C).

[0159] If siloxanes (C) are used, they are preferably those composed of units of general formulas (IV), (V), and (VI):

[0160] R 4 f SiO 4 / 2 (IV)

[0161] R 4 g R 5 SiO 3-g / 2 (V)

[0162] R 4 h HSiO 3-h / 2 (VI)

[0163] in

[0164] R 4 and R 5Based on the definitions given above,

[0165] f = 0, 1, 2, or 3

[0166] g = 0, 1, or 2, and

[0167] h = 0, 1, or 2

[0168] The condition is that each molecule has at least two Rs. 5 A group and at least two Si-bonded hydrogen atoms.

[0169] Examples of organopolysiloxanes (C) are derived from SO 4 / 2 R 4 3SiO 1 / 2 R 4 2R 5 SiO 1 / 2 and R 4 2HSiO 1 / 2 Those composed of units (referred to as MP resins), wherein these resins may additionally contain R 4 SiO 3 / 2 and R 4 2SiO unit, and also basically composed of R 4 2R 5 SiO 1 / 2 R 4 2SiO and R 4 HSiO unit (where R) 4 and R 5 Straight-chain organopolysiloxanes (as defined above) are composed of linear organopolysiloxanes.

[0170] The organopolysiloxane (C) preferably has an average viscosity of 0.01 to 500,000 Pa*s, more preferably 0.1 to 100,000 Pa*s, measured at 25°C in each case by means of a rheometer calibrated with a cone-plate system CP50-2 having an opening angle of 2° and a viscosity of 1s. 1 The shear rate.

[0171] Organopolysiloxanes (C) are commercially available or can be produced by standard methods.

[0172] The addition-crosslinked silicone composition may be selected from the group consisting of:

[0173] - In each case, at least one compound (A), (B), and (D) are present.

[0174] - In each case, at least one compound (C) and (D), and

[0175] - In each case, at least one compound (A), (B), (C), and (D)

[0176] in

[0177] (A) is an organic compound or an organosilicon compound containing at least two groups having aliphatic carbon-carbon double bonds.

[0178] (B) is an organosilicon compound containing at least two Si-bonded hydrogen atoms.

[0179] (C) is an organosilicon compound containing Si-C-bonded groups, having aliphatic carbon-carbon multiple bonds and Si-bonded hydrogen atoms, and

[0180] (D) is a hydrogen silanization catalyst.

[0181] Based on the total weight of the silicone composition, the silicone composition typically contains 30-95% by weight, preferably 30-80% by weight, and more preferably 40-70% by weight of (A).

[0182] Based on the total weight of the silicone composition, the silicone composition typically contains 0.1-60% by weight, preferably 0.5-50% by weight, and more preferably 1-30% by weight of (B).

[0183] If the silicone composition contains component (C), then based on the total weight of the silicone composition, the formulation typically contains 30-95% by weight, preferably 30-80% by weight, and more preferably 40-70% by weight of (C).

[0184] Depending on the total weight of the components, the amount of component (D) can be between 0.1 and 1000 parts per million (ppm), between 0.5 and 100 ppm, or between 1 and 25 ppm of platinum group metals.

[0185] The amounts of all components present in the silicone composition are selected such that their total amount does not exceed 100% by weight based on the total mass of the silicone composition.

[0186] The hydrosilylation catalyst (D) used can be any catalyst known in the art. Component (D) can be a molybdenum group metal, such as molybdenum, rhodium, ruthenium, palladium, osmium, or iridium, an organometallic compound, or a combination thereof. Examples of component (D) are compounds such as hexachloromolybdic (IV) acid, molybdenum dichloride, molybdenum acetylacetonate, and complexes of said compounds encapsulated in a matrix or core-shell structure. Platinum complexes of low molecular weight organopolysiloxanes include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complexes with platinum. Other examples are platinum phosphite complexes, platinum phosphine complexes, or alkyl platinum complexes. These compounds can be encapsulated in a resin matrix.

[0187] The concentration of component (D) is sufficient to catalyze the hydrosilylation reaction of components (A) and (B) upon contact to generate the heat required in the described method. Depending on the total weight of the components, the amount of component (D) can be between 0.1 and 1000 parts per million (ppm), between 0.5 and 100 ppm, or between 1 and 25 ppm of platinum group metals. When the content of platinum group metals is below 1 ppm, the curing rate can be low. Using more than 100 ppm of platinum group metals is uneconomical or can reduce the stability of the adhesive formulation.

[0188] The silicone composition preferably comprises a platinum complex of general formula (VII):

[0189] R 3 3Pt{CpR 4 5-r-t [(CR2) n SiR 1 o R 2 p ] t [SiR 7 s R 8 3-s ] r}(VII)

[0190] In equation (VII),

[0191] Cp represents cyclopentadienyl group.

[0192] n is an integer from 1 to 8.

[0193] o is 0, 1, 2, or 3.

[0194] p is 0, 1, 2, or 3, and the condition is o + p = 3.

[0195] r is 1, 2, 3, 4 or 5, preferably 1, 2 or 3, more preferably 1 or 2, especially 1.

[0196] t can be 0, 1, 2, 3, or 4, preferably 0 or 1, more preferably 1, provided that r + t ≤ 5, preferably 3.

[0197] s can be 0, 1, or 2, preferably 2.

[0198] R can be the same or different, and can be a hydrogen atom or a monovalent unsubstituted or substituted hydrocarbon group.

[0199] R 1 They can be the same or different, and are monovalent unsubstituted or substituted hydrocarbon groups, which can be interrupted by heteroatoms.

[0200] R2 They can be the same or different, and can be hydrolyzable groups or oxygen-bonded silyloxy groups.

[0201] R 7 They can be the same or different, and are monovalent unsubstituted or substituted aliphatic saturated hydrocarbon groups (which can be interrupted by heteroatoms), or oxygen-bonded silyloxy groups.

[0202] R 8 They can be the same or different, and represent aliphatic unsaturated, optionally substituted groups.

[0203] R 3 They can be the same or different, and are monovalent unsubstituted or substituted aliphatic saturated hydrocarbon groups.

[0204] R 4 They can be the same or different, and can be hydrogen atoms, SiC-bonded silyl groups, or unsubstituted or substituted hydrocarbon groups that can be interrupted by heteroatoms.

[0205] Examples of such platinum complexes having the chemical formula (VS) are:

[0206] Trimethyl[(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0207] Trimethyl[((2-methylallyl)dimethylsilyl)cyclopentadienyl]platinum(IV),

[0208] Trimethyl[(trimethoxysilyl)methyl(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0209] Trimethyl[(2-trimethoxysilyl)ethyl(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0210] Trimethyl[(3-trimethoxysilyl)propyl(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0211] Trimethyl[(3-dimethoxymethylsilyl)propyl(allyldimethylsilyl)cyclopentadienyl]-platinum(IV),

[0212] Trimethyl[(4-trimethoxysilyl)butyl-(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0213] Trimethyl[(2-trimethoxysilyl)-1-methylethyl(allyldimethylsilyl)cyclopentadienyl]-platinum(IV),

[0214] Trimethyl[(3-trimethoxysilyl)-2-methyl-2-propyl(allyldimethylsilyl)cyclopentadienyl]-platinum(IV),

[0215] Trimethyl[bis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0216] Trimethyl[bis(2-methylallyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0217] Trimethyl[(trimethoxysilyl)methylbis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0218] Trimethyl[(2-trimethoxysilyl)ethylbis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0219] Trimethyl[(3-trimethoxysilyl)propylbis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0220] Trimethyl[(4-trimethoxysilyl)butylbis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0221] Trimethyl[(2-trimethoxysilyl)-1-methyl-ethylbis(allyldimethylsilyl)cyclopentadienyl]-platinum(IV),

[0222] Trimethyl[(3-trimethoxysilyl)-2-methyl-2-propylbis(allyldimethylsilyl)cyclopentadienyl]-platinum(IV),

[0223] Trimethyl[tris(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0224] Trimethyl[(triethoxysilyl)methyl(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0225] Trimethyl[(triacetoxysilyl)methyl(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0226] Trimethyl[(3-bistrimethylsilyl)methylsilylpropyl](allyldimethylsilyl)cyclopentadienyl-platinum(IV),

[0227] Trimethyl[(3-triethoxysilyl)propyl(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0228] Trimethyl[(triethoxysilyl)methylbis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0229] Trimethyl[(3-triethoxysilyl)propylbis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0230] Trimethyl[(triethoxysilyl)methyltris(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0231] Triethyl[(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0232] Tris(trimethylsilylmethyl)[(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0233] Triethyl[(trimethoxysilyl)methyl(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0234] Triethyl[(trimethoxysilyl)methylbis(allyldimethylsilyl)cyclopentadienyl]platinum(IV),

[0235] Triethyl[tris(allyldimethylsilyl)cyclopentadienyl]platinum(IV), and

[0236] Triethyl[(trimethoxysilyl)methyltris(allyldimethylsilyl)cyclopentadienyl]platinum(IV).

[0237] These platinum complexes are described, for example, in WO 2016030325 A1.

[0238] In a further embodiment, the silicone composition is a peroxidatively crosslinkable silicone material. These silicone materials can be organically crosslinked by adding an organic peroxide (as component D). In this case, the silicone composition consists of at least components (A) and (D). In this case, component (D) is preferably present in the silicone rubber compound at a weight of between 0.1% and 20%. The crosslinking agent used in component (D) can be any corresponding and typical peroxide known in the art. Examples of component (D) are dialkyl peroxides, such as 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 1,1-di(tert-butylperoxy)cyclohexane, 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, α-hydroxyperoxy-α′-hydroxydicyclohexyl peroxide, 3,6-dicyclohexylene-1,2,4,5-tetrasiloxane, di-tert-butyl peroxide, tert-butyl-tert-butyl-tert-butyl peroxide, and tert-butyltrimethyl-1,2,4,5-tetrasiloxane. Ethyl 5-methyl peroxide, diarylalkyl peroxides such as dicumyl peroxide, alkylaralkyl peroxides such as tert-butylcumyl peroxide and α,α'-di(tert-butylperoxy)-m / p-diisopropylbenzene, alkylacyl peroxides such as tert-butyl perbenzoate, and diacyl peroxides such as benzoyl peroxide, bis(2-methylbenzoyl peroxide), bis(4-methylbenzoyl peroxide), and bis(2,4-dichlorobenzoyl peroxide). Vinyl-specific peroxides are preferred, with dialkyl and diarylalkyl peroxides being the most important representatives.

[0239] Particularly preferred are the use of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and dicumyl peroxide. It is possible to use a single peroxide or a mixture of different peroxides. The content of the peroxide-crosslinkable silicone rubber compound in component (D) is preferably between 0.1% and 5.0% by weight, more preferably between 0.5% and 1.5% by weight. Therefore, a crosslinkable silicone rubber compound is preferred, characterized in that the crosslinking agent (D) is present at 0.1% to 5.0% by weight and is an organic peroxide or a mixture of organic peroxides, in each case based on the total weight of the silicone composition.

[0240] The described composition may optionally include all additional additives that have been used to date in the production of peroxide-crosslinkable and addition-crosslinkable compositions.

[0241] These additives can also be incorporated into any condensation-crosslinked silicone elastomer composition known in the art. A more detailed description of this crosslinking mode is provided, for example, in EP 0787766 A1.

[0242] Examples of optional components include (E) packing material.

[0243] Examples of reinforcing fillers that can be used as components in silicone compositions include those with a thickness of at least 50m. 2 Fumed or precipitated silica with a BET surface area of ​​ / g, and also carbon black and activated carbon such as furnace black and acetylene black, preferably having a surface area of ​​at least 50m². 2 / g of BET surface area of ​​fumed silica and precipitated silica. The silica filler mentioned may have hydrophilic properties or be hydrophobic by known methods. Based on the total weight of the silicone composition, the content of the active reinforcing filler in the crosslinkable composition is in the range of 0% to 70% by weight, preferably 0% to 50% by weight.

[0244] More preferably, the crosslinkable silicone rubber compound is characterized in that the filler (E) has been surface-treated. Surface treatment is achieved by methods known in the art for hydrophobically refining the filler. Hydrophobication can be carried out, for example, before or in the presence of the polyorganosiloxane, by an in-situ method. Both methods can be carried out batchwise or continuously. The preferred hydrophobicating agent is an organosilicon compound capable of reacting with the filler surface to form covalent bonds or permanently physically adsorbing onto the filler surface. Examples of hydrophobicating agents are alkylchlorosilanes, such as methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, octyltrichlorosilane, octadecyltrichlorosilane, octylmethyldichlorosilane, octadecylmethyldichlorosilane, octyldimethylchlorosilane, octadecyldimethylchlorosilane, and tert-butyldimethylchlorosilane; alkylalkoxysilanes, such as dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, and trimethylethoxysilane; and trimethylsilyl alcohol. Cyclic organo(poly)siloxanes, such as octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane; linear organopolysiloxanes, such as dimethylpolysiloxanes with trimethylsiloxy terminals and dimethylpolysiloxanes with silanol or alkoxy terminals; disilazanes, such as hexaalkyldisilazane, especially hexamethyldisilazane, divinyltetramethyldisilazane, and bis(trifluoropropyl)tetramethyldisilazane; cyclic dimethylsilazanes, such as hexamethylcyclotrisilazane. Mixtures of hydrophobicating agents, as detailed further, can also be used. To accelerate hydrophobication, another option is to add catalytically active additives, such as amines, metal hydroxides, and water.

[0245] Hydrophobication can be carried out, for example, by using one hydrophobic agent or a mixture of two or more hydrophobic agents in one step, or by using one or more hydrophobic agents in multiple steps.

[0246] As a result of the surface treatment, the preferred filler (E) has a carbon content of at least 0.01% to no more than 20% by weight, preferably between 0.1% and 10% by weight, and more preferably between 0.5% and 5% by weight, based on the total mass of the silicone composition. Particularly preferred are crosslinkable silicone rubber compounds, characterized in that, based on the total mass of the filler, the filler (E) is surface-treated silica having 0.01% to 2% by weight of Si-bonded aliphatic unsaturated groups. For example, these are Si-bonded vinyl groups. In the silicone rubber compound, component (E) is preferably used as a single sub-filler, or equally preferably as a mixture of multiple sub-fillers.

[0247] The silicone composition may optionally include further additions as components in proportions up to 70% by weight, preferably from 0.0001% to 40% by weight, based on the total mass of the silicone composition. These additives may include, for example, inactive fillers, resinous polyorganosiloxanes other than siloxanes (A), (B), and (C), reinforcing and unreinforced fillers, fungicides, fragrances, rheology modifiers, corrosion inhibitors, oxidation inhibitors, light stabilizers, flame retardants, and reagents affecting electrical properties, dispersants, solvents, adhesion promoters, pigments, dyes, plasticizers, organic polymers, heat stabilizers, etc. These include additives such as ground quartz, diatomaceous earth, clay, chalk, zinc barium white, carbon black, graphite, graphene, metal oxides, metal carbonates, metal sulfates, metal salts of carboxylic acids, metal dust, fibers, nanofibers such as glass fibers, polymer fibers, polymer powders, metal dust, dyes, and pigments.

[0248] These fillers can also be thermally or electrically conductive. For example, conductive fillers can be used to create a conductive silicone layer, which can then be used as an electrode layer in sensors, actuators, or other EAP systems. Examples of thermally conductive fillers are aluminum nitride; alumina; barium titanate; beryllium oxide; boron nitride; diamond; graphite; magnesium oxide; granular metals such as copper, gold, nickel, or silver; silicon carbide; tungsten carbide; zinc oxide; and / or combinations thereof. Thermally conductive fillers are known in the art and are commercially available. For example, CB-A20S and Al-43-Me are alumina fillers with different particle sizes available from Showa-Denko, and AA-04, AA-2, and AAl-8 are alumina fillers available from Sumitomo Chemical Company. Silver fillers are commercially available from Metalor Technologies USA, Attilaboro, Massachusetts, USA. Boron nitride filler is commercially available from Advanced Ceramics Corporation, Cleveland, Ohio, USA.

[0249] These reinforcing fillers include silica and short fibers, such as short... Fibers. Combinations of fillers with different particle sizes and particle size distributions can be used.

[0250] The silicone composition may also contain one or more optional components. Examples of optional components include (F) one or more solvents and (G) one or more inhibitors.

[0251] The silicone composition may optionally include (F) one or more solvents. However, it should be ensured that the solvent has no adverse effect on the overall system. Suitable solvents are known in the art and are commercially available. Solvents can be, for example, organic solvents having 3 to 20 carbon atoms. Examples of solvents include aliphatic hydrocarbons, such as nonane, naphthane, and dodecane; aromatic hydrocarbons, such as mesitylene, xylene, and toluene; esters, such as ethyl acetate and butyrolactone; ethers, such as n-butyl ether and polyethylene glycol monomethyl ester; ketones, such as methyl isobutyl ketone and methyl pentyl ketone; siloxane fluids, such as linear, branched, and cyclic polydimethylsiloxanes, and combinations of these solvents. The optimal concentration of a specific solvent in an adhesive formulation can be readily determined by routine testing. Depending on the weight of the compound, the amount of solvent may be between 0% and 95% by weight, or between 1% and 95% by weight, based on the total weight of the silicone composition.

[0252] Inhibitors (G) and stabilizers are used to control the processing time, initiation temperature, and crosslinking rate of silicone compositions in a targeted manner. These inhibitors and stabilizers are well-known in the field of addition-crosslinking compositions. Examples of commonly used inhibitors are alkynyl alcohols, such as 1-ethynyl-1-cyclohexanol, 2-methyl-3-butyn-2-ol, and 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-dodecyn-3-ol, and polymethylvinylcyclosiloxanes such as 1,3,5,7-tetravinyltetramethyltetracyclosiloxane, having methylvinyl-SiO 1 / 2 Groups and / or R2 vinyl SiO 1 / 2Low molecular weight silicone oils with terminal groups, such as divinyltetramethyldisiloxane, tetravinyldimethyldisiloxane, trialkyl cyanurate, alkyl maleate esters, such as diallyl maleate, dimethyl maleate, and diethyl maleate, alkyl fumarate esters, such as diallyl fumarate and diethyl fumarate, organohydroperoxides, such as cumene hydroperoxide, tert-butyl hydroperoxide, and pinane hydroperoxide, organic peroxides, organosulfur oxides, organic amines, diamines and amides, phosphine and phosphites, nitrile, triazole, diaziridines, and oximes. The effects of these added inhibitors (E) depend on their chemical structure and therefore their concentrations must be determined individually. Based on the total weight of the mixture, inhibitors and inhibitor mixtures are preferably added in proportions of 0.00001% to 5%, preferably 0.00005% to 2%, and more preferably 0.0001% to 1%.

[0253] After all components of the silicone composition have been mixed, in 1 second -1 The dynamic viscosity at the shear rate is between 10 mPa·s and 1000 Pa·s, preferably between 100 mPa·s and 100 Pa·s, and more preferably between 200 mPa·s and 50 Pa·s. This was measured according to DIN EN ISO 3219:1994 and DIN 53019 using a calibrated rheometer with a cone-plate system and a CP50-2 cone having an opening angle of 2° at 25°C and a 1s... -1 The shear rate.

[0254] A suitable measuring instrument is the MCR302 rheometer, available from Anton Paar GmbH in Austria (105 μm gap width).

[0255] The advantages of crosslinkable silicone compositions are that they can be produced using readily available starting materials in a simple and therefore economically viable manner. Crosslinkable compositions also have the advantage of exhibiting good storage stability as a single-component formulation at 25°C and ambient pressure, and crosslinking rapidly only at elevated temperatures. In the case of two-component articles, after the two components have been mixed, they produce a crosslinkable silicone composition that remains processable for a long period at 25°C and ambient pressure, i.e., exhibiting an extremely long pot life, and crosslinking rapidly only at elevated temperatures.

[0256] Examples of commercially available silicone compositions are as follows (depending on the viscosity of the material, a solvent may be added to obtain better processability):

[0257] Materials from WACKER Chemie AG: P series (7010, 7600, 7613, 7161-160, 7616-195, 7618, 7619, 7622, ​​7623, 7624, 7628, 7629, 7630, 7633, 7636, 7642-220, 7670, 671, 7676, 7682, 7683 / 15, 7683 / 25, 7683 / 47, 7683 / 50, 7683 / 55, 7684 / 60, 7685, 7686, 7687, 7688, 7700, 7710, 7720, 7731, 7742, 7770, 7707US, 7915, etc.) M series (4115, 4125, 4370, 4400, 4440, 4441, 4470, 4600, 4601, 4615, 4630, 4635, 4640, 4645, 4641, 4643, 4644, 4670, 4647, 4648, 4670), RT series (601, 602, 604, 607, 615, 617, 619, 620, 622, 623, 624, 625, 626, 627, 628, 629, 630, 633, 646, 670, 672, 675, 678, 685, etc.) SOLAR series (2000, 2200, 2202, 3210, etc.) LR series (3003 / 03, 3003 / 05, 3003 / 10, 3003 / 20, 3070 / 20, 3844 / 20, 3846 / 20, 3856 / 20, 3003 / 30, 3004 / 30, 3005 / 30, 3040 / 30, 3044 / 30, 3065 / 30, 3070 / 30, 3071 / 3) 0, 3072 / 30, 3843 / 30, 3844 / 30, 3846 / 30, 3856 / 30, 3003 / 40, 3003 / 50, 3003 / 60, 3003 / 70, 3003 / 80, 3003 / 85, 3004 / 40, 3004 / 50, 3004 / 60, 3004 / 70, 3005 / 40, 3 005 / 50, 3005 / 60, 3040 / 40, 3040 / 50, 3040 / 60, 3043 / 40, 3043 / 50, 3043 / 60, 3043 / 70, 3015 / 70, 3023 / 60, 3092 / 65, 3094 / 60, 3065 / 50, 3066 / 40, 3066 / 60, 3066 / 80, 3070 / 40, 3070 / 50, 3070 / 60, 3071 / 40, 3071 / 50, 3071 / 60, 3072 / 40, 3074 / 60, 3076 / 70, 3170 / 40, 3841 / 50, 3842 / 40, 3842 / 50, 3842 / 60, 3842 / 70, 3162, etc.), FLR series (3900 / 40, 3900 / 60, 3905 / 40, 3905 / 60, etc.) R series, WACKER Series (610, 611, 612, 613, 616, 619, etc.) series, series, series, series, series, series.

[0258] In addition to the crosslinkable silicone compositions described above, non-curable silicone compositions, such as silicone oils, are also available for applying additional layers. In this context, the following products from WACKER Chemie AG, Germany, are available. AK SILICONOEL series FLUID TR series series.

[0259] Typically, silicone-based PSA (pressure-sensitive adhesive) can be used.

[0260] Even in different applications, it is advantageous to use non-curable printing materials as support materials or release layers. These compositions can then be removed from or removed from the print body without residue by rinsing and / or heating. Here, a suitable example of a printing material is polyethylene glycol (PEG). Suitable carrier materials composed of polyethers are described, for example, in WO 2017020971 A1 and WO 2018036640 A1.

[0261] Alternative support materials may also be wax, beeswax, petrolatum, paraffin wax, resin, gelatin, and generally any heat-fusible bulk. Polyethylene glycol (PEG) or wax is particularly preferred. Suitable support materials made of wax are described, for example, in WO 2018153467 A1.

[0262] As mentioned above, crosslinking mechanisms can be freely chosen and combined. In this context, WO 93000405A1 and PCT application PCT / EP2020 / 060378 (unpublished) name various combinations of UV crosslinking and moisture crosslinking. The advantage here is the crosslinking of UV-accessible compositions and the post-crosslinking of shading compositions. These positive crosslinking effects can be advantageous for printing strategies / methods using UV-opaque printing materials. It is possible to achieve shading by means of the influence of parts and / or printing materials positioned in or around the geometry, and to prevent UV crosslinking for this purpose.

[0263] Another form of printing material can be a silicone aqueous dispersion.

[0264] Preferably, prior to step (b), the plate, drive belt, external components, or previously applied layer of printing material may be detected by one or more sensor modules.

[0265] Preferably, after step (b) and / or step (c), the printing plate, printing conveyor belt and / or printing external components may also be detected by one or more sensor modules.

[0266] Therefore, the 3D printing equipment includes one or more inspection units (3, 5) configured as an inspection plate (28), a drive belt (9), an external component (7), a previously applied layer of printing material, or a printed object.

[0267] The method or apparatus of the present invention can also be used with the following methods:

[0268] - Inspection or geometric measurement of printing material during the printing process, such as as described in WO 2017108208 A1

[0269] - The height is measured using a confocal measuring device for determining the distance between the printhead and the printing surface, such as that described in WO 2018014948 A1.

[0270] - Determine the morphology of the surface to be printed and control the placement of the printing material accordingly, for example as described in PCT / EP2009 / 077812 (undisclosed).

[0271] At the end of the construction, the object may optionally undergo post-processing, in which case the post-processing is selected from one or more of the following methods: heat treatment, radiation, surface coating, engraving, cutting, segmentation and removal of fragments, assembly of individual parts, cleaning, and removal of support material.

[0272] Therefore, the 3D printing equipment includes at least one post-processing unit (4, 6) configured to perform post-processing on the printed object after printing.

[0273] In a preferred embodiment, the 3D printing equipment is a composite production equipment system, which includes one or more units described above and in detail with reference to the accompanying drawings, such as a pick-and-place unit, a printing unit, a curing unit, a processing unit, an inspection unit, a post-processing unit, and / or a removal unit.

[0274] The object is preferably heat-treated as described, for example, in WO 2010015547 A1.

[0275] In a particular embodiment, a printing material is applied such that one or more segments are formed in one or more printing planes of an object, each segment consisting only of an object-forming material or a support material.

[0276] It is also possible to print different printing materials together in order to obtain a constant mixing ratio with specific properties (for example, Shore A hardness material 20 is mixed with Shore A hardness material 60 to obtain Shore A hardness material 40).

[0277] The printing material of the object forming material can be applied, for example, in such a way as to form one or more segments in one or more printing planes of the object, each segment consisting of a mixture of two or more object forming materials, and the mixing ratio of the object forming materials in each segment is constant.

[0278] Another option is to print the materials onto each other to create gradients, such as hardness gradients (e.g., from Shore A20 to Shore A60), conductivity gradients (e.g., from conductive to non-conductive), or magnetic gradients (e.g., from magnetic to non-magnetic).

[0279] In addition, print voxels of various printing materials can be applied to form one or more segments within one or more printing planes of the object, each segment consisting of a mixture of two or more object-forming printing materials, wherein the mixing ratio of the object-forming printing materials undergoes a gradient in each segment.

[0280] For example, a description of such segments and gradients is disclosed in WO 2019063094 A1.

[0281] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0282] exist Figure 1 The diagram describes a scheme for a composite production equipment system. An automatic pick-and-place unit (8) precisely positions the blank / external part (7) to be printed onto a conveyor belt (9), which then guides it into the factory assembly. The conveyor belt is then withdrawn from a belt storage device / belt feeder (10) and held under mechanical tension. After being introduced into the 3D printing unit (2), the blank / external part (7) to be printed and / or new individual 3D parts are printed.

[0283] After this printing process, the parts produced are transferred to the inspection unit (3) via a conveyor belt (9). Various measurements are then taken and the parts are inspected.

[0284] After inspection by the inspection unit (3), these parts are transferred to the post-processing unit (4) via the conveyor belt (9). Different post-processing steps can be performed here. Post-crosslinking and heat treatment are preferred.

[0285] These parts are then conveyed to the second inspection unit (5) via conveyor belt (9) and measured again. After that, they are transferred to the final processing unit (6) via (9).

[0286] In the final processing unit (6), all the final physical steps before being discharged from the system are performed.

[0287] In this case, the following steps are preferred:

[0288] -Heat treatment to release carrier material

[0289] - Cutting components using lasers and ultrasonic scalpels

[0290] -Engrave and print part numbers

[0291] - Rinsing and washing

[0292] - Surface treatment (plasma treatment)

[0293] After all printed parts (11) and / or newly created 3D printed bodies (12) have been ejected, the parts are removed using an automatic removal unit (13). At the end of the system, the drive belt is collected in a belt storage device (18).

[0294] All units (8, 2, 3, 5, 6, 13) existing in the composite production system (1) are connected to the overall controller / data processing system (14) via a data interface / data connection (15). All process data, print data, measurement data, and print geometry, etc., are processed in the data processing system (14) according to different links and data processes. The database system (16) stores all relevant process data and measurement data used for quality control and product documentation. All data and process parameters are input through the input system (17).

[0295] Figure 2 A diagram of the printing unit (2) is shown. Using a lock (25), a conveyor belt (9) carrying a blank (7) is fed to and removed from the printing unit (2). All introduced parts and the conveyor belt (9) are electrostatically discharged before printing via a pre-discharge module (29). Printing materials and / or support materials are positioned via these printing modules (20). The printing materials are cross-linked via a curing module (22). The positioned material, the blank (body) to be printed (7), the printed blank (body) (11), and the individual 3D printed parts (12) are electrostatically charged to a potential phi_2 via an electrostatic charging / discharging module (23). Geometric and physical data are detected and used for printing processing using a sensor module (21). All modules move in the Y direction on a platform (27) via a movement axis Y (24). The platform (27) secures the conveyor belt (9) to a vacuum plate (28). The platform (27) moves precisely in the Z direction via the moving axis Z (26) and establishes a corresponding distance from the target surface (59) to be printed. The adjustment accuracy here corresponds to a printing accuracy and layer thickness in the range of less than 1 mm. Preferably less than 0.1 mm and more preferably less than 0.01 mm.

[0296] Figure 3A diagram of the inspection unit (3) is shown. A conveyor belt (9) containing the printed blanks (11) and the individual 3D-printed parts (12) is fed to and removed from the inspection unit using a lock (25). These printed blanks (11) and these individual 3D-printed parts (12) are measured by a sensor module (30). Here, the conveyor belt (9) is again fixed and adjusted in position and regarding the flatness of the vacuum plate (35) of the contact plate (34) and the moving axis Z (33). To further adjust the separation and movement in the X direction (in the plane of the page), the moving axes X and Z (32) of the sensor module (30) are used. The advantage of using different Z-moving units is that axes with different precision and speeds can be used for different tasks.

[0297] The sensor module (30) can have a variable configuration. It can include various optical distance measurement devices, laser triangulation sensors, confocal sensors, ultrasonic, IR measurement technologies, polarization measurement technologies, spectrometers and / or electromagnetic measurement technologies, such as eddy current sensors or coaxial sensors.

[0298] Preferably, the following parameters are determined in this inspection unit:

[0299] - Component measurement (confocal, laser triangulation, ultrasonic)

[0300] - Conductivity (eddy currents, electromagnetic measurements)

[0301] -Cure state (via transmission IR spectroscopy)

[0302] These two test units (3) and (4) have comparable constructions and can determine the same or different properties.

[0303] Figure 4 A diagram depicts the post-processing unit (4). A conveyor belt (9) carrying the printed blank (11) and the 3D-printed individual parts (12) is fed to and removed from the post-processing unit using a lock (25). Post-processing of the bodies (11) and (12) is performed using two curing modules (40) and (44). The upper post-processing unit (40) is positioned here by the moving axis Y (41) and the moving axis Z (42). The lower post-processing unit (44) is positioned by the moving axis Z (45). Process parameters, such as surface temperature, are measured non-contactly using a sensor module (43).

[0304] Post-processing is performed to achieve complete cross-linking of the printing material.

[0305] These post-processing modules can be configured, for example, as follows:

[0306] -Heat (e.g., IR, hot air, heating elements)

[0307] - Radiation (e.g., UV, UV lasers, NIR / MIR lasers)

[0308] - Electron beam

[0309] Processing time, methods, and modules vary depending on the printing material and its composition.

[0310] Figure 5 A cross-sectional view of the printing module (20) is shown. The printing material layer / electrode material layer (54) is separated from the carrier roller (51) by means of a laser beam (50a) emanating from a laser source (50). Separation is achieved in the separation zone (55). The laser beam (50a) causes heating, resulting in evaporation / gas formation / thermal expansion of at least one component of the printing material / electrode material (54). In the case of standard LIFT processing, the separation of the printing material layer (54) is sufficient to position the separated printing material (57) on the target surface (59). A precise layer of printing material (54) is applied by the application system (52) by means of the counterclockwise rotation of the carrier roller (51). After separation by the laser (51), the remaining printing material and the separation zone (56) move to the removal system (53), where all residual printing material is removed from the carrier roller (51). The material removed here is reprocessed and reused.

[0311] In the specific case of the LIFT process using silicone elastomers, this improvement in separation and positioning can be achieved by additionally charging the printed material (54) and the target surface region (59). This involves using an electric potential... For the printing material (54), with electric potential For the target surface and with electric potential The vacuum plate (28) is charged. The polarity of the potential should be chosen here to generate opposite charges. These layers generate an electric field (E) with charges spaced apart by a distance (h). These, in turn, exert a force on the printing material (54) in the direction of the target surface (59). As a result, the separated printing material (57) is accelerated by electrostatic force and moves in the direction of the target surface (59). The separated printing material (57) is subjected to considerable mechanical shear force during separation and impact. An advantageous material composition (shear-thinning silicone) here has an advantageous effect in the formation of continuous printing material layers. (58) The shear-thinning silicone composition is described, for example, in WO 2017081028 A1, WO2017089496 A1 and WO 2017121733 A1. In addition, the electrostatic force of the residual charge in the placed printing material 58 acts in the direction of the vacuum plate (28). For the presence of a potential The presence of charge relaxation on the target surface (59) at the surface is advantageous to be to a degree smaller than the charge level of the printed material (58) on which it is placed. Any residual charge on the material (58) should be selected such that any effect on the field (E) is as small as possible, but the relaxation of the printed material (58) is accelerated or improved.

[0312] In many known implementations of the LIFT method, a reference laser beam is focused onto the interface between the printing material 54 and the carrier system 51. In embodiments using silicone, focusing above the carrier produces a better printed image. Here, the focal point (50b) is located from a few micrometers to a few millimeters above the interface between the carrier roller (51) and the printing material (54). Focusing the laser beam onto, within, or below the interface initially causes separation (55), but this subsequently results in considerable further heating on the target surface (59) and may therefore lead to burning or thermal degradation of the applied printing material (58).

[0313] A laser beam (50a) is also available to heat these positioned printing materials and for dot crosslinking. The feeding of printing materials is shut off here, and the carrier roller without a layer of printing material is purely transmissive. By defocusing, the introduced energy is directed onto the printing plane and applied in a controlled manner over a defined diameter. Therefore, a separate curing unit (e.g., IR, oven) is not required.

[0314] Furthermore, the controlled introduction of power can achieve crosslinking not only through the laser system (50), but also through the melting, sintering, engraving, and cutting of various printing materials. The curing and subsequent process steps, as described above in unit (6), can therefore also be combined in a single device.

[0315] In a specific implementation, the printing material / support material is used in conjunction with a heat-fusible material (such as wax or PEG). This includes a heated carrier roller (51), an application system (52), and a removal system (53). It is possible that a heating element is present within the carrier roller (51) and / or any heat supply system (e.g., heat transfer oil or hot air) is used.

[0316] In a specific embodiment, the carrier roller and the build space of the printer can be cooled. The purpose of this design is to prevent unwanted cross-linking of the printing material as much as possible.

[0317] Figure 6A diagram depicting the material flow of the printing material. Supply system 60 supplies new printing material to the printing system. System (60) consists of two metering units (61) and (62) for a two-component printing material consisting of components A and B. Mixing system (63) is used to mix the two materials A and B and supply them to another mixing system (67). Mixing system (67) mixes the new printing material with the reprocessed printing material. The thus mixed printing material is supplied to the print head (2) or application system (52). In the recycling processing unit (64), the recycled material from the removal system (53) is reprocessed. Processing system (64) consists of a mechanical (first) processing system (65) and a second processing system (66). Mechanical processing includes crushing and filtering. The second processing operation includes degassing, wetting, or decolorizing, and optionally adding additional components of the printing material formulation (e.g., the printing material formulation itself, such as solvents, water, catalysts, crosslinking agents, etc.).

[0318] The advantages of this invention are summarized again as follows:

[0319] • It enables the use of variable printing materials with different properties (e.g., variable viscosity) and compositions in a single printing system.

[0320] • Capable of achieving a high material throughput of over 1 kg / h.

[0321] • Lower wear because only a few components that move mechanically at high speeds are used (e.g., no nozzles are required, as in spray methods).

[0322] • Voxel size and layer thickness can be variably adjusted via the application system and laser.

[0323] • High print quality achieved through stable distance adjustment of a fixed-position carrier roller (e.g., the film carrier does not flatten).

[0324] • It is possible to use small cylinders, thus resulting in low mechanical tolerances.

[0325] • As far as radiation passes through the surface of the free cylinder is concerned, the size and construction space of the laser source are not limited.

[0326] • Low net area of ​​printing material on the carrier system (low air contact).

[0327] • High precision (possible voxel size <100μm).

[0328] The optional use of a drive belt means that several manual operation steps are eliminated.

[0329] • The optional use of electron beams enables rapid crosslinking of printed materials without the need for crosslinking catalysts.

[0330] • The use of a laser (50) for curing / additional applications enables new degrees of freedom in the additive manufacturing process. This allows for, for example, new curing strategies (which can establish point crosslinks) and the parallel execution of removal, application, and curing in a single device.

[0331] The following experiments were conducted to demonstrate a comparison of the various functional modes in accordance with the principles of the invention. These experiments are intended to provide a better understanding of the invention and should not be considered limiting relative to the invention as detailed above and described with reference to the accompanying drawings.

[0332] The LIFT process was performed using a standard laser gravure system from TROTEC Laser Deutschl GmbH. The system used was a dual-laser source system from the Speedy 100flexx 60 / 20 series (60W 10.6μm CO2 laser; 20W 1.06μm fiber laser). The printing material carrier was a standard 300mm high-resistivity, polished silicon wafer from Siltronic AG, Germany. The printing material film was applied using a ZAA2300 automatic film applicator, which incorporates the ZUA2000 universal applicator from Zehntner GmbH, Switcherl. The printing material used was... RT 625A / B, from WACKER Chemie AG, RTV-2 silicone from Germany.

[0333] Experiment 1: LIFT method

[0334] A uniform layer, 100 μm thick and 150 x 150 mm in size, is applied to the center of a wafer on one side using a doctor blade system. The edge areas of the wafer remain free of printing material. An uncoated and clean glass plate, serving as the surface to be printed, is inserted into the laser's cutting space. The coated wafer is turned to face the uncoated glass plate on the cutting side and positioned on the glass plate at a distance of 200 μm. This distance is adjusted using spacers (e.g., 100 μm microscope plates). The printing subject selected in the laser system's control software is a two-dimensional filled geometry without gray areas or shadows. Furthermore, with a 60W laser, a laser power of 20%-40% in gravure mode is sufficient. The laser speed should be selected between 30% and 60%. The focus should be 2-3 mm above the interface between the coating and the wafer. This allows transfer through the geometry selected by the laser.

[0335] Experiment 2: EFLIFT method

[0336] Silicone membrane (via water film) A 100 μm thick silicone film (available from WACKER Chemie AG) was fixed onto a glass plate. The top of the silicone film was then charged to -300V using a high-voltage charging system from Simco-Ion, consisting of the CM LITE series and HDR charging electrodes. Charge measurements were verified using an SK050 electrostatic meter and an SK1000 evaluation unit from Keyence. The printed material layer on the wafer was charged to approximately +100V. It is crucial to ensure no unintentional discharges occur and to handle the semiconductor wafer safely after and during the filling of the printed material. The two plates were then repositioned in the laser's cutting space. The distance between the printed material and the silicone film can be selected from 100 μm to 400 μm with spacers. The LIFT operation should be performed similarly to the description above. Without the aforementioned loading, the separated printed material is transferred in a somewhat incomplete or non-specific manner. Furthermore, charging resulted in more uniform deposition and better adhesion of the transferred layers.

[0337] Experiment 3: Laser curing

[0338] The silicon wafer is removed, and the transferred layer is crosslinked by direct laser irradiation. Here, a 60W laser in gravure mode with a power between 10% and 40% is sufficient. The laser speed should be selected between 10% and 60%. The focus should be 1 to 2 mm above the interface between the coating and the wafer. Complete crosslinking may require multiple laser passes. Partial crosslinking or the degree of crosslinking can also be adjusted by varying the number of passes and the laser power.

[0339] Reference numerals in the attached figures

[0340] Figure 1 Composite production equipment system

[0341] 1. 3D Composite Production Equipment

[0342] 2 3D Printing Units

[0343] 3 Inspection Unit

[0344] 4 Post-processing units

[0345] 5 Inspection Units

[0346] 6. Final Processing Unit

[0347] 7. Printable blank (body)

[0348] 8 pick-and-place units

[0349] 9. Transmission belt

[0350] 10 with storage device / with feeder

[0351] 11. Print blank (body)

[0352] 12 3D printed individual parts / 3D printed bodies

[0353] 13 Remove Unit

[0354] 14 Overall Controller / Data Processing System

[0355] 15 Data Interface / Data Connection

[0356] 16 Database Systems

[0357] 17 Input System

[0358] 18 Tape storage media

[0359] 19 Unused

[0360] Figure 2 3D printing unit

[0361] 20 Printing Module

[0362] 21 Sensor Module

[0363] 22 Solidification Module

[0364] 23 Electrostatic charging and discharging module

[0365] 24 locks

[0366] 25. Moving axis Y

[0367] 26 Moving axis Z

[0368] 27 Platform

[0369] 28 Vacuum Plate

[0370] 29 Pre-discharge module

[0371] Figure 3 Inspection unit

[0372] 30 Sensor Modules

[0373] 31 Moving axis Y

[0374] 32. The moving axis Z of the sensor module

[0375] The Z-axis of the 33 platform

[0376] 34 Platform

[0377] 35 Vacuum Plate

[0378] 36 Unused

[0379] 37 Unused

[0380] 38 Unused

[0381] 39 Unused

[0382] Figure 4 Post-processing unit

[0383] 40 Upper Post-processing Module

[0384] 41. The moving axis Y of the upper post-processing module

[0385] 42. The Z-axis of movement of the upper post-processing module

[0386] 43 Sensor Module

[0387] 44 Lower Post-Processing Module

[0388] 45. The Z-axis of movement of the lower post-processing module

[0389] 46 Unused

[0390] 47 Unused

[0391] 48 Unused

[0392] 49 Unused

[0393] Figure 5 Printing module

[0394] 50 laser sources

[0395] 50A laser beam

[0396] The focal point of the 50b laser beam

[0397] 51 Carrier Roller

[0398] 52 Application Systems

[0399] 53 Remove System

[0400] 54 Printing material layers

[0401] 55 Separation area of ​​printing material

[0402] 56. Area on the carrier roller where printing material is separated.

[0403] 57 Print voxel / Separate printing material

[0404] 58 Positioning Printing Material

[0405] 59 Surface to be printed

[0406] Figure 6Material flow diagram

[0407] 60 Printing Material Supply Units

[0408] 61 Dosing unit for printing material used for reactant component A

[0409] 62 Dosing units for printing material used for reactant component B

[0410] 63 Hybrid System

[0411] 64 Recycling and Processing Units

[0412] 65 Mechanical (First) Processing System

[0413] 66 Second Processing System

[0414] 67. Mixer for old and new materials

[0415] 68 Unused

[0416] 69 Not used.

Claims

1. A method of layer-by-layer production of an object by laser transfer printing in a 3D printing device, the 3D printing device comprising: at least one plate (28), at least one laser source (50) and at least one carrier drum (51); wherein the material of the carrier drum (51) is transparent to a laser beam (50a) from the laser source (50) and the laser source (50) is arranged above the carrier drum (51), wherein the method comprises the following steps: (a) coating at least a portion of the outer surface of the carrier drum (51) with at least one printing material (54); (b) irradiating the carrier drum (51) with a laser beam (50a) from the laser source (50) such that at least a portion of the applied printing material (54) is detached from the carrier drum (51) and transferred to the plate (28), to an external component (7) positioned on the plate (28) or to a previously applied printing material layer; wherein the irradiation is effected in such a way that the laser beam (50a) impinges the printing material (54) applied on the underside of the carrier drum (51) directly from the outside of the carrier drum (51) through both walls of the carrier drum (51), (c) forming a printing material layer by solidifying the printing material (54) transferred in step (b), (d) repeating steps (a) to (c) until the object is completely constructed.

2. The method according to claim 1, wherein a conveyor belt (9) is movably arranged on the plate (28) and in step (b) the printing material (54) is detached from the carrier drum (51) and transferred to the conveyor belt (9), to an external component (7) positioned on the conveyor belt (9) or to a previously applied printing material layer.

3. The method according to claim 1 or 2, wherein prior to step (b) the printing material (54) applied to the carrier drum (51) is charged to a potential phi_1 and the plate (28) is charged to a potential phi_3, wherein phi_1 and phi_3 have opposite polarity.

4. The method according to claim 3, wherein the surface of the external component (7), the surface of a previously applied printing material layer and / or the surface of the conveyor belt (9) is additionally charged to a potential phi_2, wherein phi_2 and phi_1 have opposite polarity and phi_2 is chosen such that at least a portion of the electric charge on the printing material (54) transferred in step (b) is neutralized on the surface to be printed.

5. The method according to claim 1 or 2, wherein the carrier drum (51) is rotated and in step (a) an application system (52) applies a layer comprising printing material (54) to the carrier drum (51) and after step (b) non-detached printing material (54) is removed from the carrier drum (51) by a removal system (53).

6. The method according to claim 1 or 2, wherein the printing material used is one or more of the following object-forming materials: silicone, polyacrylate, polyolefin, polyurethane, polyurea, polynitrile, polyester, polyether, polylactic acid, polyhydroxyal-kanoate, and mixtures, solutions, dispersions or copolymers comprising one or more of the aforementioned object-forming materials.

7. The method according to claim 1 or 2, wherein at least one printing material is selected from the group consisting of cross-linkable silicone elastomer compositions, silicone gels, silicone resins, silicone oils and silicone dispersions.

8. The method of claim 1 or 2, wherein, The printing material used additionally comprises one or more support materials which are removed after the object has been constructed.

9. The method according to claim 1 or 2, wherein the focal point (50b) of the laser beam (50a) is chosen such that the focal point (50b) is in the range from 0.01 mm to 10 mm above the interface between the printing material (54) and the carrier drum (51) within the carrier drum.

10. The method of claim 2, wherein, The plate (28) is a movable vacuum plate which fixes the transmission belt (9) used in step (b) at a specific distance from the coated carrier drum (51).

11. The method according to claim 2, wherein prior to step (b) and prior to any charging to the potential phi_2 or phi_3, the surface to be printed on the plate (28), the transmission belt (9), the outer part (7) or a previously applied layer of printing material is electrostatically discharged by a pre-discharge module (29).

12. The method according to claim 1 or 2, wherein the material of the carrier drum (51) is selected from the group consisting of glass, quartz glass, polyethylene terephthalate, polycarbonate, polyimide, polymethyl methacrylate, ZnSe, ZnS, BaF2, CaF2, Ge, KBr, NaCl, MgF2, LiF and Si.

13. A 3D printing device for producing objects by laser transfer, comprising: - at least one laser source (50); - at least one carrier drum (51), wherein the material of the carrier drum (51) is transparent to the laser beam (50a) from the laser source (50), - at least one application system (52) arranged to coat at least one part of the outer surface of the carrier drum (51) with at least one printing material (54); - at least one plate (28), wherein the laser source (50) is arranged above the carrier drum (51) and is arranged to irradiate the carrier drum (51) such that at least one part of the printing material (54) applied to the carrier drum (51) is detached and transferred to the plate (28), to an outer part (7) located on the plate (28) or to a previously applied layer of printing material, wherein the 3D printing device is arranged such that the laser beam (50a) hits the printing material (54) applied on the lower side of the carrier drum (51) directly from the outside of the carrier drum (51) through both walls of the carrier drum (51).

14. The 3D printing device according to claim 13, wherein a drive belt (9) is movably arranged on the plate (28).

15. The 3D printing device according to claim 13 or 14, wherein the 3D printing device comprises at least one charging / discharging module (23) arranged to charge the surface of the printing material (54) applied to the carrier drum (51), the surface of the plate (28) and / or the target surface to be printed, each independently, to a specific electric potential phi.

16. The 3D printing device according to claim 13 or 14, wherein the 3D printing device comprises at least one solidification module (22) arranged for solidifying the printing material (54).

17. The 3D printing device according to claim 13 or 14, wherein the 3D printing device comprises at least one removal system (53) arranged to remove printing material (54) not separated from the carrier drum (51).

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