JP3579798B2 - Stereolithography fabrication method and metal structure manufacturing method using the same - Google Patents
Stereolithography fabrication method and metal structure manufacturing method using the same Download PDFInfo
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- JP3579798B2 JP3579798B2 JP12929794A JP12929794A JP3579798B2 JP 3579798 B2 JP3579798 B2 JP 3579798B2 JP 12929794 A JP12929794 A JP 12929794A JP 12929794 A JP12929794 A JP 12929794A JP 3579798 B2 JP3579798 B2 JP 3579798B2
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/10—Processes of additive manufacturing
- B29C64/106—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
- B29C64/124—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified
- B29C64/129—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified characterised by the energy source therefor, e.g. by global irradiation combined with a mask
- B29C64/135—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified characterised by the energy source therefor, e.g. by global irradiation combined with a mask the energy source being concentrated, e.g. scanning lasers or focused light sources
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- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
- Laser Beam Processing (AREA)
- Moulds For Moulding Plastics Or The Like (AREA)
- Heating, Cooling, Or Curing Plastics Or The Like In General (AREA)
Description
【０００１】
【産業上の利用分野】
本発明は、光造形ファブリケ−ションによって光硬化性樹脂よりなる立体的な３次元構造物を製造する方法に関し、特に精度として１μｍ程度、原理的にはより微細な精度を有する立体的な３次元構造物を光造形ファブリケ−ション法によって製造する光造形ファブリケ−ション法に関する。
【０００２】
【従来の技術】
光造形法はＣＡＤシステムによって所望の立体形状を設計したデ−タをコンピュ−タで高さ方向に等間隔の水平面で切断してスライス図形のデ−タ群を作製し、他方、液状の光硬化性樹脂を満たしたタンク内に液面よりｄの位置にテ−ブルをセットし、先に作製したスライス図形デ−タの中で最下端のものを取り出し、このスライス形状に沿ってレ−ザビ−ムをガラス等の透明な板で規制されている液面に照射して前記スライス図形デ−タに対応した形状を有する厚さｄの平板状の樹脂板を成形し、次にテ−ブルをｄだけ降下させ、固化した樹脂板上に未硬化の樹脂液が厚さｄとなるように存在させ、これに第２層のスライス図形デ−タの形状に沿ってレ−ザビ−ムを前述の場合と同様に液面上を走らせて固化させ、第１層の場合と同様に第２層のスライス図形デ−タに対応した形状を有する厚さｄの平板状の樹脂板を成形する。しかして、この第２層の固化部分は第１層の固化部分と自然に接合する。このようにして第３層、第４層・・・・と順次同様の操作を行うことによって、全体が固化した所望の立体形状をした成形物が得られる。（第１図参照）。すなわち、光造形法は、このようにスライス図形デ−タをもとにして順次光硬化樹脂を硬化させて三次元構造物を製造する方法である。
【０００３】
ところで、光硬化性樹脂は、一般に粘度が高いので樹脂を注入すると液面に凹凸が生じ、これらが元の平滑な水平面に戻るためにはある程度の時間を要する。この時間的なロスを防止するため、通常樹脂液の液面をガラス等の透明な規制板を使用して液面の水平面を保ち、この規制板を通して樹脂液面に光を照射している。
しかし、この方法では硬化した樹脂と透明な規制板との間の接着性が問題となり、このために得られる３次元構造物の精度は数ｍｍ程度のものに制約される。また、精度を高めるためにレ−ザビ−ムの径を小さくして樹脂の硬化部分の径を小さくする必要がある。しかし、レ−ザビ−ムの径を小さくすると、ビ−ムの焦点深度が深さ方向に大となり、その結果、硬化部が長くなって、ミクロンオ−ダの硬化精度を有する構造物を得ることはできなかった。
【０００４】
【発明が解決しようとする課題】
そこで、本発明者は上記の欠点を改良し、上記製造方法において、３次元微細構造物を高精度で製造するため種々検討した結果、本発明を完成したもので、本発明の目的は高精度をもって３次元微細構造物を光造形ファブリケ−ション法によって製造する方法を提供するものである。
【０００５】
【課題を解決するための手段】
本発明の要旨は、液状の光硬化性樹脂を用い光造形法により３次元構造物を製造する光造形ファブリケ−ション法において、透明な板で規制された前記液状の光硬化性樹脂の液面に気泡を介して光を照射して光硬化性樹脂を硬化させることを特徴とする光造形ファブリケ−ション法であり、その際液状の光硬化性樹脂中に光透過度調整剤を添加して光の樹脂中への透過度を調整することが好ましい。
【０００６】
すなわち、本発明では気泡によって樹脂と透明規制面との間を常時分離させて樹脂と規制面との間の接着を防止し、これによって精度を高め、また、その際、光透過度調整剤を液状の光硬化性樹脂中に添加し、レ−ザビ−ムの樹脂中へレ−ザビ−ムの透過深度を制限し、レ−ザビ−ムの径に対する透過深度の長さの比、即ちアスベクト比を１に近づけて硬化形状を球形にして精度を高めるものである。
【０００７】
以下本発明について詳細に述べる。
本発明の光造形ファブリケ−ション法は、先に述べた光造形法と、その操作は何等異ならない。そして、本発明で使用する光硬化性樹脂についても光造形法で使用されるものは何れも使用することができ、例えば、ポリエステルアクリレ−ト、ポリウレタンアクリレ−ト、ノボラック型エポキシ樹脂、ビスフェノ−ル型エポキシ樹脂等で、これにアセトフェノン系、ベンゾイル系、ベンジルケタ−ル系或いはケトン系の光開始剤を添加したものである。
【０００８】
また、照射に使用する光としては、Ｈｅ−Ｃｄレ−ザ、アルゴンレ−ザ、クリプトンレ−ザ等の紫外線レ−ザや、キセノンランプ、水銀ランプ等の紫外線ランプ等である。
ＣＡＤシステム上で設計した数値モデルをコンピュ−タで高さ方向に等間隔の水平面で切断してスライス図形（断面図形）のデ−タを作成するに際してスライスの間隔が細かい程、表面形状が細かく好ましいが、通常、１μｍ〜５μｍの範囲に設定して行なう。
また、液面を規制する透明な規制板は従来よりこの種の光造形法において使用されているものであれば良い。
【０００９】
本発明においては、気泡を介して光を照射するのであるが、気泡の大きさ等は単に透明な規制板と硬化された樹脂とが接着しなければどのような寸法でも良く、通常径が１ｍｍ以下のものが好ましく、また、気泡が先端部より移動しないように光源の鏡胴先端部が凹状に形成されていることが好ましい。その際、透過度を調整する手段としては光吸収剤或いは染料等を添加すればよく、具体的にはアクリル系染料等が挙げられる。
【００１０】
本発明を図面をもって説明する。図１は光造形方法の説明図である。図において液状樹脂液１を入れた容器２をＸＹステ−ジ３上に載置する。樹脂液内には液面規制板４が置かれ、その液面を平らにする。ＸＹステ−ジ３はＣＡＤシステムデ−タによって制御用コンピュ−タを作動し、これにより左右前後に移動し、また規制板４はＺ軸ステ−ジ３’によって上下に移動でき、この上下移動は制御用コンピュ−タ９によってコントロ−ルされる。この樹脂面の上方に光源５が固定されており、光源５の光はシャッタ−６及び集光レンズ７を通して樹脂の表面に集光される。
あるＣＡＤシステムより得られたスライス第１層のデ−タを制御用コンピュ−タによってＸＹステ−ジ制御、シャッタ−制御及び２軸ステ−ジ制御によって第１層のデ−タにもとづいた形状の硬化樹脂板を得る。続いて第２層……と順次それぞれの樹脂板を得て最終的に全体像のものを創製する。
【００１１】
このような装置において、本発明では気泡を介して光を照射するのであるが、その状態を図２に示す。図２において、光束は集光レンズ７を通り、透明規制板４の中央に設けて凹状部内にある気泡８を介して集光させて樹脂を硬化させる。
本発明の方法によって得られた光硬化樹脂よりなる成型物を鋳型とし、これに電鋳により金属を埋め込んだ後、樹脂を除去することによって、微細な金属成形物が得られる。
【００１２】
【実施例】
次に実施例をもって、更に具体的に本発明を説明する。
実施例１
図１において、透明規制板の中央に図２に示すような凹状部を設け、この中に気泡８を存在させた装置を用いて、レ−ザビ−ムを集光して樹脂を硬化して３次元構造物を成形した。光硬化性樹脂としては、アクリル系樹脂を使用し、これに光透過度調整剤としてアクリル系染料を添加して光透過度を調整してアスペクト比（入射光の焦点深度／入射光の径）を１０とした。得られた３次元構造物の寸法は１００×１００×１００μｍで作成に要した時間は約１時間程度であった。
【００１３】
【発明の効果】
本願発明の方法によって得られる成形物の精度は極めて高く、微細のものであり、従来、この種の物の成形法であるシリコンプロセス、異方性エッチング、放電加工、ＬＩＧＡプロセス、レ−ザＣＶＤ法等に比して次のような長所を有する。
１．完全な３次元構造の実現が可能である。
２．高精度の物が得やすい。
３．高アスペクト比のものを製造することができる。
４．高速生産性、量産性を有する。
５．装置が簡単で低コシトで作成できる。
６．ランニングコストも低い。
７．有毒ガスや爆発性ガスは一切使用しないので安全性が高い。
８．省スペ−ス
９．金属等樹脂以外の素材でも容易に転写可能である。
【図面の簡単な説明】
【図１】光造形ファブリケ−ション法の説明図
【図２】本発明にかかる光造形ファブリケ−ション法における集光部分の拡大説明図
【符号の説明】
１ 液状光硬化性樹脂液 ２ 容器 ３ ＸＹステ−ジ
３’ Ｚ軸ステ−ジ ４ 透明規制板 ５ 光源
６ シャッタ− ７ 集光レンズ ８ 気泡 ９ 制御用コンピュ−タ[0001]
[Industrial application fields]
The present invention relates to a method of manufacturing a three-dimensional three-dimensional structure made of a photocurable resin by stereolithography fabrication, and particularly, a three-dimensional three-dimensional structure having a precision of about 1 μm and in principle finer accuracy. structure stereolithography the Faburike - stereolithography prepared by Deployment method Faburike - about the Deployment method.
[0002]
[Prior art]
The stereolithography method uses a CAD system to cut the data designed in a desired three-dimensional shape on a horizontal plane at equal intervals in the height direction with a computer to produce a slice figure data group. A table is set at a position d from the liquid level in a tank filled with a curable resin, and the lowermost one of the slice graphic data prepared earlier is taken out, and the table along the slice shape is taken out. The surface of the liquid regulated by a transparent plate such as glass is irradiated to form a flat resin plate with a thickness d having a shape corresponding to the slice graphic data. The bull is lowered by d, and an uncured resin liquid is present on the solidified resin plate so as to have a thickness d, and the laser beam is formed along the shape of the slice graphic data of the second layer. Run on the liquid surface in the same way as described above to solidify the first layer as in the case of the first layer. Slice shape data of the layer - forming a flat resin plate having a thickness of d having a shape corresponding to the data. Thus, the solidified portion of the second layer naturally joins with the solidified portion of the first layer. In this way, by performing the same operations in the order of the third layer, the fourth layer,..., A molded product having a desired solid shape that is solidified as a whole is obtained. (See FIG. 1). That is, the optical modeling method is a method of manufacturing a three-dimensional structure by sequentially curing the photo-curing resin based on the slice graphic data as described above.
[0003]
By the way, since the photocurable resin generally has a high viscosity, when the resin is injected, irregularities are formed on the liquid surface, and it takes some time for these to return to the original smooth horizontal surface. In order to prevent this time loss, the liquid level of the resin liquid is usually maintained by using a transparent regulating plate such as glass, and the resin liquid level is irradiated with light through the regulating plate.
However, in this method, the adhesion between the cured resin and the transparent regulating plate becomes a problem, and the accuracy of the three-dimensional structure obtained for this purpose is limited to a few millimeters. In order to improve accuracy, it is necessary to reduce the diameter of the laser beam and reduce the diameter of the cured portion of the resin. However, if the diameter of the laser beam is reduced, the depth of focus of the beam increases in the depth direction. As a result, the hardened portion becomes longer, and a structure having a micron order hardening accuracy is obtained. I couldn't.
[0004]
[Problems to be solved by the invention]
Therefore, the present inventor has improved the above-mentioned drawbacks, and as a result of various studies for manufacturing a three-dimensional microstructure with high accuracy in the above manufacturing method, the present invention has been completed, and the object of the present invention is high accuracy. The present invention provides a method for manufacturing a three-dimensional microstructure by an optical modeling fabrication method .
[0005]
[Means for Solving the Problems]
The gist of the present invention is the liquid level of the liquid photocurable resin regulated by a transparent plate in the photofabrication fabrication method for producing a three-dimensional structure by a photomolding method using a liquid photocurable resin. This is a photofabrication fabrication method characterized by irradiating light through air bubbles to cure the photocurable resin. At that time , a light transmittance adjusting agent is added to the liquid photocurable resin. It is preferable to adjust the transmittance of light into the resin .
[0006]
Namely, by constantly separated between the resin and the transparent restricting surface by gas bubbles in the present invention to prevent the adhesion between the resin and the restricting surface, thereby increasing the accuracy, At that time, the light transmittance adjusting agent Added to the liquid photocurable resin to limit the penetration depth of the laser beam into the resin of the laser beam, the ratio of the length of penetration depth to the diameter of the laser beam, ie The ratio is made close to 1 to increase the accuracy by making the cured shape spherical .
[0007]
The present invention is described in detail below.
The stereolithography fabrication method of the present invention is not different from the stereolithography described above in terms of operation. As the photocurable resin used in the present invention, any of those used in stereolithography can be used, for example, polyester acrylate, polyurethane acrylate, novolac epoxy resin, bisphenol. This is an epoxy resin or the like, to which an acetophenone, benzoyl, benzyl ketal or ketone photoinitiator is added.
[0008]
Examples of light used for irradiation include ultraviolet lasers such as He—Cd laser, argon laser, and krypton laser, and ultraviolet lamps such as xenon lamp and mercury lamp.
When a numerical model designed on a CAD system is cut on a horizontal plane at equal intervals in the height direction on a computer to create slice figure (cross-section figure) data, the finer the surface shape is, the finer the slice interval is. Although it is preferable, it is usually set in the range of 1 μm to 5 μm.
Moreover, the transparent control board which controls a liquid level should just be used in this kind of optical modeling method conventionally.
[0009]
In the present invention, light is irradiated through bubbles, but the size of the bubbles may be any size as long as the transparent regulating plate and the cured resin do not adhere to each other, and the normal diameter is 1 mm. The following are preferable, and it is preferable that the front end of the lens barrel of the light source is formed in a concave shape so that the bubbles do not move from the front end. At that time, as a means for adjusting the transmittance, a light absorbent or a dye may be added, and specifically, an acrylic dye or the like may be mentioned.
[0010]
The present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram of an optical modeling method. In the figure, a container 2 containing a liquid resin solution 1 is placed on an XY stage 3. A liquid
The shape of the first layer data obtained from a certain CAD system based on the first layer data by XY stage control, shutter control and two-axis stage control by a control computer. A cured resin plate is obtained. Subsequently, the second layer and so on are sequentially obtained, and finally the whole image is created.
[0011]
In such an apparatus, in the present invention, light is irradiated through bubbles, and the state is shown in FIG. In FIG. 2, the light beam passes through the
A molded product made of a photocurable resin obtained by the method of the present invention is used as a mold, a metal is embedded in this by electroforming, and then the resin is removed to obtain a fine metal molded product.
[0012]
【Example】
Next, the present invention will be described more specifically with reference to examples.
Example 1
In FIG. 1, a concave portion as shown in FIG. 2 is provided in the center of the transparent regulating plate, and using a device in which bubbles 8 are present, the laser beam is condensed to cure the resin. A three-dimensional structure was formed. Acrylic resin is used as the photo-curable resin, and an acrylic dye is added as a light transmittance adjusting agent to adjust the light transmittance to adjust the aspect ratio (the depth of focus of incident light / the diameter of incident light). Was set to 10. The dimension of the obtained three-dimensional structure was 100 × 100 × 100 μm, and the time required for preparation was about 1 hour.
[0013]
【The invention's effect】
The accuracy of the molded product obtained by the method of the present invention is extremely high and fine. Conventionally, silicon molding, anisotropic etching, electric discharge machining, LIGA process, laser CVD, which are molding methods of this type. It has the following advantages over the law.
1. Realization of a complete three-dimensional structure is possible.
2. It is easy to obtain highly accurate products.
3. High aspect ratio products can be manufactured.
4). High speed productivity and mass productivity.
5). The device is simple and can be created with low cost.
6). The running cost is also low.
7). Since no toxic gas or explosive gas is used, safety is high.
8). Space saving 9. It is possible to easily transfer materials other than resin such as metal.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a stereolithography fabrication method. FIG. 2 is an enlarged explanatory diagram of a condensing portion in the stereolithography fabrication method according to the present invention.
DESCRIPTION OF SYMBOLS 1 Liquid photocurable resin liquid 2 Container 3 XY stage 3 'Z-
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12929794A JP3579798B2 (en) | 1994-06-10 | 1994-06-10 | Stereolithography fabrication method and metal structure manufacturing method using the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12929794A JP3579798B2 (en) | 1994-06-10 | 1994-06-10 | Stereolithography fabrication method and metal structure manufacturing method using the same |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004166725A Division JP4034758B2 (en) | 2004-06-04 | 2004-06-04 | Manufacturing method of metal structure using stereolithography fabrication method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07329188A JPH07329188A (en) | 1995-12-19 |
| JP3579798B2 true JP3579798B2 (en) | 2004-10-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| JP12929794A Expired - Fee Related JP3579798B2 (en) | 1994-06-10 | 1994-06-10 | Stereolithography fabrication method and metal structure manufacturing method using the same |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3161362B2 (en) | 1997-05-01 | 2001-04-25 | 富士ゼロックス株式会社 | Microstructure, its manufacturing method, its manufacturing apparatus, substrate and molding die |
| JP4500962B2 (en) * | 2004-07-26 | 2010-07-14 | 国立大学法人横浜国立大学 | Manufacturing method of microstructure |
| CN106378939A (en) * | 2015-08-07 | 2017-02-08 | 优克材料科技股份有限公司 | Three-dimensional printing device |
| CH711890A1 (en) * | 2015-12-04 | 2017-06-15 | Coobx Ag | Additive manufacturing device. |
| EP3894184B1 (en) * | 2018-12-10 | 2024-01-17 | BMF Precision Technology (Wuxi) Inc. | Methods of controlling dimensions in projection micro stereolithography |
-
1994
- 1994-06-10 JP JP12929794A patent/JP3579798B2/en not_active Expired - Fee Related
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| Publication number | Publication date |
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| JPH07329188A (en) | 1995-12-19 |
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