Method and device for the lithography-based additive manufacture of three-dimensional molded bodies

Abstract

The invention relates to a method for the lithography-based additive manufacture of three-dimensional molded bodies, wherein a construction platform (8) is positioned at a distance from a material support (1), which is permeable at least in some regions to the radiation of a radiation source, for a material which can be solidified under the effect of the radiation. The material support (1) is moved in a translational manner between a first position and a second position. The invention is characterized in that material is deposited with a defined layer thickness during the movement of the material support (1) from the first position to the second position. The applied material is then irradiated and solidified by the radiation source in a location- and / or time-selective manner between the construction platform (8) and the material support (1), and the material is then removed from the material support (1) during the movement of the material support (1) from the second position to the first position.

Description

[0001] Method and device based on lithography;

[0002] additive manufacturing of three-dimensional mold bodies

[0003] The invention relates to a method for

[0004] lithography-based additive manufacturing of

[0005] dr i.dirriensA.onalen For;skorpern , in which a building block at a distance from a material permeable to radiation from a ray angle is positioned for a material that is solidified by the action of the radiation, wherein the material angle is moved translationally between a first and a second position.

[0006] The invention further relates to a device rar

[0007] Conducting such a procedure,

[0008] X of the lithographic or stereolithographic;

[0009] Additive manufacturing uses photoplasticizable materials.

[0010] The process is carried out layer by layer into shaped bodies, with each layer being selectively positioned either by an optical mask or a projected image.

[0011] Biidflache or by means of fiberst rahin onto the au poiyraer. iaierende material. Here, korarrit es su fundamental distinctions in dar fbahi der

[0012] Exposure?:.- and structuring method: It can

[0013] On the one hand, a (submersible) basin of a photopolymerizable material is exposed from above, whereby the

[0014] The structured object is successively immersed in the liquid material during production (SLA) ... or a material reservoir (filled material vat) is exposed from below through a transparent vat bottom, whereby the object is exposed from above out of the material bath { DL?, Laaet'-'Stereorithography ; , In the latter case, the object is structured layer by layer by moving it up and down, whereby the respective distance m sc eu object and material vat provides a highly precise

[0015] Layer thickness guaranteed. In novel processes, this type of strotaring can also be done continuously (no

[0016] alternating A-ob- and ho-- kovegang more) successful, whereby then further special Änforäerangea at the

[0017] The tub floor can be placed on top of the tub. A major advantage of lighting through the aquarium tub compared to the

[0018] The main advantage of the described submersible process (SLA) is the significantly lower material requirement for starting the process, since many bits of the reactive material are used in submersible processes.

[0019] If consumption data is needed, these are available.

[0020] Handling and process costs are inherent disadvantages.

[0021] All of the above-mentioned Prceneseiethogea eeneh u is the high

[0022] geometric quality of the additively structured

[0023] He results. Of all; In the field of plastics technology, this surface quality is crucial, so that it can compete with common processes such as injection molding applications. Image-based 3D printing therefore stands out clearly from all other available SD printing processes in terms of surface and form quality. However, the high requirements for the viscosity of the starting materials (polymer mixtures) are a disadvantage in this regard. The currently required dynamic viscosity in;

[0024] The processing time for iadin:m should therefore not exceed a few Pa,s (Pascal seconds). This hurdle de

[0025] Layering processes drastically limit the selection of image-correcting photopolymers, thus causing the greatest weakness of lithography-based additive layering processes; the standardized, severely limited

[0026] Material properties of the processed materials, especially for technical applications, but also in the area of ​​end-user products, are important in addition to the geometric consistency of an object, above all its material quality.

[0027] "Only departing" In additively processed plastics, acknowledged deficiencies are changing, especially in the

[0028] Temperature loss (significant loss of stiffness / E-modulus at higher temperatures ~ usually already from 40-50°C) ' C) or the elasticity (impact strength / resistance to fatal breakage or cracking). ambient temperature ,

[0029] Materials suitable for bilithographic processing rMaterials exhibiting a combination of strength, toughness, and sufficient temperature resistance (e.g., sufficient stiffness up to 80°C) are currently considered a prerequisite for the successful and widespread integration of additive stereolithography processes into existing product technology. However, such materials are currently either unavailable or only partially available in the desired quality.

[0030] To develop novel photopolymer systems for

[0031] The processes that develop into bileoliths are primarily the aforementioned V ' Risk requirements of known

[0032] Processing processes are problematic; until a possible solution is found, a process at elevated temperature has proven effective; even a slight increase in temperature is noticeable.

[0033] Process temperature compared to normal room temperature (20 s 0) The viscosity of most

[0034] Photopolymer grass iserm This results in a significant increase in the cur selection available.

[0035] Starting polymer substances are achieved, which in the fourth phase will lead to novel 3D printing materials. Applications of heated process systems are already publicly acknowledged. Another possibility of

[0036] Processing higher viscosity SystSine consists of the

[0037] Process control itself; where, for example, it may involve the removal of iron tau cysts (material trays with a filling depth of several millimeters or centimeters) by means of

[0038] other methods of material introduction ίη,B,;

[0039] To replace the ingrowth system, increased process temperatures can also bring a decisive advantage with these approaches, although the

[0040] The temperature sensitivity of the phthalopolymer being processed must be considered. Elaborate heating of individual free re cor: :de or the genier: krozes combs can remedy this, but often also results in

[0041] considerable mechatronic effort and, if implemented incorrectly, can affect the longevity of the

[0042] rhotopo 1 Vitergemischea neraöacc ins and thereby the

[0043] Process stability can be significantly jeopardized. The aim of the present invention is therefore to...

[0044] Process control Cef of processing high viscosity darre tu find which combines the advantages of selective heating of individual process sections with the advantages of a

[0045] defined material input into this process zone

[0046] combined and soft as long-term stable

[0047] The invention proposes a solution to this problem in a production system, essentially a method in which material is moved from the first to the second position with a defined...

[0048] Layered diake is applied; then the

[0049] Applied material between the building platform and the material interface, selected in terms of location and / or time from the

[0050] The radiation source is irradiated and solidified, and

[0051] subsequently material during the movement of the

[0052] Material removal from the second position is carried away from the first position.

[0053] The present invention consists of a coating process in which a photosensitive substance in the form of thin films can be applied to an exposure zone. The process utilizes a

[0054] translationally movable material support f The bspsu, designed as a material substrate, which mainly serves as a support plate for the process-dependent thin films of the photosensitive material, is now referred to as photopolymerizable material, which can consist of pure photosensitive mono- or oligomeric compounds or of such compounds including a photoinitiator component. Furthermore, such a compound can also contain organic or inorganic fillers.

[0055] may contain and / or other organic or inorganic additives or other substances, dyes, absorbents or otherwise functional or non-functional renal agents.

[0056] Containing ingredients. It may also include other photopolymerizable substances, provided that a lithographic interaction with this material is possible.

[0057] A wavelength range between ISOnm and 950nm is possible.

[0058] The material is preferably applied using a stationary

[0059] Material insertion device applied. At gen protrude and has thereby a f in relation to the experienceable

[0060] Material flow, fixed process position. Preferably, the material is provided that it is removed by a first and a second doctor blade. The first doctor blade is preferably positioned before or during the

[0061] Movement of the material a running lay from the second to the first position perpendicular to the direction of movement of the

[0062] The material is moved away from the material and preferably during or before the movement of the material from the first or second position to set the defined layer thickness towards the material running surface. The first package is thus designed fThe height of the first doctor blade, in a z-eii chtuny (perpendicular to an xk : cetera in which the material feed is moved), is variable and divisible by 1 / 2, whereby this height adjustment can be controlled by both active iζ,B, a doctor blade torque, and passive pressure mechanisms. The first doctor blade can preferably be adjusted in its cdde such that it does not in the lowest position.

[0063] Rakel gap between the first squeegee and the

[0064] Materialauriage rul.asst, and thus the

[0065] dal er h Leinbringεv rri chteng o11 βtänd5.g gesoh loscc.c ist. oder sonst dass sie in ein aufgehobene Stellung eine Lückehöhe von wenig d i. Kreon i: ern bis hoch so einige.:! Millimetern zalasut .

[0066] The second doctor blade forms an ibzocroeckavh soes and is either passively or actively adjustable in its delivery level (z-dlicrn- Inno; ). Preferably, it is provided ethat the second rake raithiife of a rnckstalie iements, e.g., a spring, is held in relation to the material iaiauflage.

[0067] This ensures that the material insertion device is at least partially sealed at all times against the photosensitive material contained within it.

[0068] It is preferably provided that a material reservoir is located between the first and second doctor blades. It is particularly preferred that, during the movement of the material surface from the second to the first position, material removed from the material surface is at least partially fed back into the material reservoir. It is particularly preferred that, during the movement of the material surface from the first to the second position, the material is drawn from the material reservoir through a gap defined between the first doctor blade and the material surface, with the material passing through the gap and the

[0069] The defined ponioh thickness is applied at the transient velocity of the material coating.

[0070] The invention-based method sifts out a

[0071] Linear conveying motion of the material support under the

[0072] Material introduction 3 device f so, in front of the first

[0073] Bakel and the second squeegee, in such a way that during a forward movement of the material i laufsage (i.e. from the first position to the second positron) a defined

[0074] Thin layer of the photo-polyunstable material onto the substrate at least partially and on parts of the

[0075] Material coating is applied and that in the case of a

[0076] Return journey of the mater iaiaufrage (i.e., from the second

[0077] Position in the first position) the remaining

[0078] The photosensitive material is partially removed from the material layer, resulting in a clean or partially cleaned surface on the removed part of the material layer, and also allowing the previously remaining photosensitive material to be partially stirred back into the materializing reservoir.

[0079] The applied thin layer of photosensitive material is introduced into a light-angle column during the material application process, in a soft, local and side-side-side-sensitive manner.

[0080] BslichtungeinforK!ation von. der dem Material abschlechten Reite der Mate iaiaufrage zugegeben ist. In einer

[0081] In preferred .Running tours, this happens, for example, from below, with the direction information being the

[0082] Material loads pass mass , The material loads are used for this purpose as opposite the : ' ;

[0083] Light information on transparent or at least

[0084] Executed, after exposure and selective curing of the photopolymerizable material, this is to the

[0085] Material layers are removed, leaving poly-encoded residues of the photosensitive material in a discontinuous thin film, or in clusters of material in material clusters, material islands, or other layer patterns. During the return of the material layer, this material is returned to the rateri reservoir.

[0086] If the first squeegee can be actively or passively raised during the return movement of the material layers, the passage of the non-polyerized material residues below the first squeegee blade is to be facilitated, after the end of the return movement of the material layers the first squeegee

[0087] The material is lowered immediately and actively or passively to prevent leakage of the photopolymerizable material from the material reservoir. During the return movement of the material feeder, the photosensitive material is detached from the bottom of the material feeder using the second doctor blade, thereby preventing it from contaminating the material reservoir. The described process can be repeated as often as desired, ensuring that a freshly applied layer of photopolymerizable material is always deposited onto the material and then fed into the heating zone. The height or thickness of this applied photosensitive material layer can now be determined by the height difference of the first doctor blade, as well as the linear...

[0088] Stepless adjustment of the material support speed, for example: Lee. The possibilities include...

[0089] Height increments of the photosensitized layer are not in the range of a few micrometers to a few millimeters. The maximum achievable layer thickness of the

[0090] The photosensitive properties of the material also depend on the viscosity of the photosensitive material, as well as its properties; 1 ehe : neuacta .f Leu, which in turn are usually temperature-dependent, in order to do justice to this aspect u : earth f Before it is said that it is intended that the material in the hyaluronic injection device is heated. Furthermore, all relevant process parts can be included in a preferred quotation form. r such as the first and / or second doctor blade and / or also the selective application of material and / or

[0091] individually customizable, heated design Vierden, The one for the actual stereolithographic

[0092] Dr. sckoreuress used hanplsttfornp soft der- to

[0093] Polymerization v forwoeoeh-r: hchichtspali mechanical

[0094] sets {along the s~Acb.se > and softens after the

[0095] Polymerization the removal of the selectively polymerized ten

[0096] Material layers of the linearly movable

[0097] Material loads are preferably designed to be heated. During the described process, there is always a photosensitive vice versa in the material reservoir. Through the alternating linear movement of the

[0098] Material loads under the material reservoir Force: it leads to a cyclic movement of the photoseracit iaen

[0099] lOrrstsnta aeria is in Ma keriaireservoir in Form von

[0100] movable or significant cranes 1 len or

[0101] biatetialwai zen Oes photosensitive. he ialc , Zur

[0102] Optiab.ercng of process control it is now advantageous to continuously or at defined intervals actively or passively detect the hateriaistand of the photosensitive material, as in ivx of the invention.

[0103] Measurement can be carried out using a diode sensor, optical sensor, or contact sensor; other, unmentioned feedback devices, such as switches, pushbuttons, level probes, or similar, can also be used to measure the fill level of the photosensitive material in the reservoir. To maintain the desired fill level of the photosensitive material in the reservoir, it is preferably provided that material is introduced into the reservoir by means of a conveying device.

[0104] For example, it may be intended that new [unclear] positions are continuously, or in the desired lateral [unclear] positions.

[0105] "Pheuioserasitive material can be introduced into your material reservoir." This conveying system can be selectively and individually controllable.

[0106] The linear material application can be used in; furthermore, also the desired. AbiÖseprotess of the selective

[0107] Carrion-hardened photoseactive material from the

[0108] Material deposits in the clearing cone, active or passive

[0109] Unterstetten, however; the linear movement of the

[0110] Material loading combined with an active or passive tilting motion of the entire process setup relative to the build platform, or also combined with an active or passive tilting motion of the build platform itself relative to the process setup, defined or

[0111] An undefined multiaxial peeling process of the cured photosensitive material from the build platform leads to such a combined peeling movement that comes as close as possible to an ideal peeling process. Preferably, the build platform tilts from the second to the first position during the movement of the material. In a preferred embodiment, this peeling process of the selectively cured photosensitive material is determined by the linear stroke of the build platform (in the z-direction), the passive or active rotation of the build platform around a pivot point guided by the build platform, and an active or passive linear transient deflection of the material, which together allow a multiaxial peeling process. To support this peeling process, the build platform can be provided with a special non-stick coating and / or made of a laminate of various materials. f for the used

[0112] Working environment of the photopermeable

[0113] Exposure process t ramsparerrce , or at least

[0114] semi-transparent materials consist»

[0115] The described process according to the invention allows the precise processing of highly viscous photosensitive starting materials, which can also have a high molecular weight and which may exist at room temperature as non-fluid or even as solid bodies. Furthermore, the described

[0116] The refill system ensures high process reliability. f since only such quantities of photosensitive material need to be present in the protein matrix; ez a stable

[0117] Druclopro is necessary» Further phosphatidical

[0118] Vorra srosterial. can up to. its use as de

[0119] The Froness zone is kept out, and any negative long-term effects caused by the freezing temperature or other environmental influences can be largely prevented. The application of the photosensitive material only in defined thin films on the material at i aqe further enables control before possible

[0120] Air inclusions in a layer of the cured material

[0121] Photopolymers ε , On the linear decay rate qness of the piateriaia aflux, the fill level of the photosensitive

[0122] Materials in the material reservoir, as well as the travel height of the doctor blade, can also influence the cyclically reversing material rollers in the material reservoir insofar as the mixing between fresh and photosensitive material already removed from the Hateria running surface is affected.

[0123] Material optimized, as well as the unwanted introduction of air or gas bubbles into the material stock.

[0124] him.er .1 l eser 1— ; r ioinimiert can be.

[0125] According to another aspect of the invention, a

[0126] The device is designed for lithography-based additive manufacturing of three-dimensional objects; and emits a radiation source, i.e., electromagnetic radiation, at least in some areas for the radiation of the

[0127] Radiation source, permeable material surface for a material that can be destroyed by the action of radiation, a building plate that is held at a distance from the material surface, wherein the material surface is movable between a first and only second position. f characterized by the fact that a

[0128] Pkateri aleinbrrnqonqsvorriohtang is provided, which is designed to apply material during the movement of the eteriaiaeiiage from the first to the second position with a defined layer thickness and to apply material during the movement of the material aafiage '; to remove material from the second to the first position.

[0129] It is preferably intended that the

[0130] Materia leinbri.egnegsvörriohtuag has at least a first and a second squeegee, wherein preferably the first squeegeekreent is directed towards the movement of the t- : ve aai aaj ; erv

[0131] It is height-adjustable.

[0132] Deiters is before rü t provided that the second rake l rrd. eineir; Rückstelieletnen , hspw. . einer Feder, zaaaeur-enwi rkt in a preferred embodiment is provided that the Baaplattforrr: is arranged to be tiltable.

[0133] It is preferably intended that the

[0134] Mater ; a 1einbr. Laguegs orrioh ieng eine is i aeinr iehtimq zurrs Erweraien des Materials aulweist,

[0135] Furthermore, it is preferably provided that a masonry reservoir is formed between the first and the second doctor blades, which are preferably arranged parallel to each other.

[0136] Preferably, the material reservoir is connected to a conveying device so that the material can be introduced into the material reservoir.

[0137] The invention is explained in detail, based on examples shown in the Bavarian State Archives. Figures 1 and 2 show schematic side sectional views of an invention device.

[0138] Device in successive phases of the

[0139] Procedure description. In Fig. 1, a material application is shown, on which a material layer 11 is arranged. A building platform is arranged opposite the material application 1. f The jn z-direction is higher-rise and ns the axis 4 is mounted to tilt. Between the construction site · ;: and the material layer 1, some material layers 11 are already built up. The material layer 1 is along the f perpendicular to the z direction; x-space movable translationally.

[0140] Furthermore, a material delivery instruction 3

[0141] The device comprises a first doctor blade 5 and a second doctor blade 6. The first doctor blade 5 is height-adjustable in the a-direction by means of a doctor blade motor 10, and the second doctor blade 6 has a spring that holds the second doctor blade 6 in the s-direction in contact with the material i running surface I. A material reservoir 2 is located between the two doctors blades 5, 6.

[0142] trained, the aüthlife of a support facility 9 can be supplied with material.

[0143] In the phase shown in Fig. 1 of the journey

[0144] The material edition 1 is located in the second

[0145] Position. Construction platform 8 is located in the direction of the

[0146] Material requirements reduced by 1; so that a new

[0147] Material layer II can be formed, Indians;

[0148] Material 11 is pushed onto the material support 1 by means of a radiation guide (not shown) from below through the material support 1, where it is effectively irradiated and solidified. The material layer II was applied by the first doctor blade 5 during the movement of the material support I into the second position.

[0149] Fig. 2 shows the phase after the completion of the solidification 5 of the itateria lache.cht 11. The itateria.iaufläge 1 now moves in the direction of arrow 12 from the second position towards the first position.

[0150] Equality ig the building platform 8 is easily lifted in · ·· Pi viv. narrowly, whereby the combined lifting motion of the

[0151] Q Building platform 8 and the movement of the material, ialanflege i in the direction of arrow 1 i leads to a tilting of the building platform δ on the axis 4, so that a zero iaia ia e formation of the finished material layers il from the material application 1 is favored in the manner of a sublimation process, Su these; 5 Inner the position of the axis 4 on the building platform 8 can also be arranged on the opposite type of building platform 8 in the x-direction, provided that this the

[0152] Pos u du! prores s additionally favored. That on the

[0153] Materia running days 1 remaining material 11 will be used at the ' 0 Movement of the M:; r er ; u iaai.i.nge from the second to the first position by the second doctor blade 6 removed and thereby collected again in the material reserve 2, possibly by fresh material through the conveying device

[0154] supplemented so that everyone has sufficient material cur

[0155] I am at your disposal.

[0156] Machde?n the material layer 11 has been removed by the second squeegee 6 and the material support 1 is positioned in the first position, the material support 1 is again moved against the direction of arrow 12 towards the second position by the first squeegee 5.

[0157] Material layer II is applied from the material i.al eseruoir 2 until the second position shown in Fig. i is reached. Then the building platform forra, or the building structure formed from the already completed layers 11, is placed into the

[0158] The material layer was lowered to adjust the solidifying layer thickness; whereupon further exposure and solidification of the material layer 11 was carried out.

Claims

Patent claims:

1. Method for 1 lithography-based generative Manufacturing of three-dimensional trans bodies at devx a B upl atttorra (85 at a distance from a minimum a material permeable to radiation from a source is positioned in a region (1) for a material that is hardened by the action of the radiation, wherein the material is moved translationally between a first and a second position, characterized in that material is applied with a defined layer thickness during the movement of the battery from the first to the second position; then the applied material, between the Bauplat tform (8) nnd der Materiaiaafläge (1) or time-side effect before; the Stra.hiw.nasqnelie irradiated and is solidified and subsequently material is removed during the movement of the material support (2) from the second to the first position of the material support {15.

2. Method according to claim X, characterized in that the material is used to facilitate a stationary Material introduction equipment {35 applied or is being removed» 3. folding according to one of claims 1 or 2, characterized in that the material is applied or removed with the aid of a first and a second squeegee ( 1 S , .

4. Method according to claim 3, characterized in that the first squeegee ;55 not or during the movement of the box rialauilsge (1) ΥΟΠ of the second za r harvesten position perpendicular to the direction of movement of the material on l ge (.1} vcn the material support ge {1; away is moved and preferably during or before the movement of the material supports Π. ) from the first to the second position aar setting of the 5 defined layer thickness towards the material support (1) is moved.

5. Method according to claim 3 or 4, dadaroh marked, ae between the first and the second. 10 Rakel (5, 6} a material reservoir (2) is formed. 6, method according to claim 5, characterized in that the material during the movement of the material supports (1) from the first to the second position from äer;i 15 Hat. erialre.sarvo.ir {2} over a gap defined between the first Bakel (5) and the Materiaiauf läge (1) with the gap and the translational The traversing speed of the hateriaiauflage (1) is applied to the defined layer thickness. £0 ' ? , method according to claim 5 or 6, thereby marked f that aid from a funding institution (9) is introduced into the material reservoir (2), 25 8. Method according to one of claims 3 to 7, characterized in that the second doctor blade {6) is a guide aid of a Return elements (?) , e.g. , a spring, is held in contact with the material support (1), 30 9. experienced after one of the addresses 5 to 8, characterized in that this occurs during the movement of the material support (1) from the second to the first position of The material removed by the material (I) is at least partially returned to the material reservoir (2). 10, Method according to one of claims 1 to 9, characterized in that the bankphone; (.8) during the Movement of the material supports (1) from the second to the first position tilts - 11, a method according to one of claims 2 to ICp characterized in that the material in the: material supply device (3) is heated 12 , Device for lithography-based additive manufacturing of three-dimensional form elements, in particular: . for carrying out a method according to one of claims i to 11 - comprising a radiation source le electronuusnetischer P: rah! zag, an at least partially transparent to the radiation of the st rahung source. Pz-.eri zluuid «:p Mi for a material that can be solidified by the action of radiation, a building component form (8) f the spaced apart from the material support U; is held, wherein the material support (1; is translationally movable between a first and a second position, characterized in that a material application system {3) is provided, which is designed to apply material with a defined layer thickness during the movement of the material support (1) from the first to the second position and to transfer material during the movement of the m'sterialanfiage {i} from the second to the first position of the materia lauf1 age (1) to be carried off. 13, Operation according to claim 12- characterized in that the material insertion device (3) has at least one first and a second squeegee (5 / 6} has hesitant. the first squeegee ;5; perpendicular to the Beaeungsriohtcna dar dateriaiaafläge (1) height adjustment loa r rat .. 14 « Device according to claim 13, thereby gckannse' ahnet , that the second squeegee (6; ab. t einea; Rücksteilelea;ent (?} bfw, einer Feder, casaaaaanaxrkt , 15 Device according to claim 12 or 13, thereby characterized that the Banplattfora (8) is tiltable arranged et .

16. Device according to e:. aar. of claims 12 to 10, characterized in that the Mat er i.aIei nbrirΊq vga vorrichtuag (} eine H i einri chtang iura Erwärtiisr; das Materials zeigt.

17. Device according to claims 13 to 16, characterized in that a lateriaireseraoir (z?) is formed between the first and the second fan (5, ■}, 18. Device according to claim .17, in that the data reserve (2) is connected to a conveying device, so that the battery can be introduced into the material reserve (2).

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