JP4444982B2

JP4444982B2 - Manufacturing method of molded body

Info

Publication number: JP4444982B2
Application number: JP2007106716A
Authority: JP
Inventors: 章弘内藤; 数利焼本; 司白銀屋; 伊東　　宏; 崇落岩
Original assignee: Japan Steel Works Ltd
Current assignee: Japan Steel Works Ltd
Priority date: 2007-04-16
Filing date: 2007-04-16
Publication date: 2010-03-31
Anticipated expiration: 2027-04-16
Also published as: JP2008265001A

Description

本発明は、成形体の製造方法に関するものであり、詳しくは、表面に微細な凹凸部を有する成形体を、その凹凸形状を良好に維持しながら、金型から迅速に、容易に、かつ確実に離型することのできる成形体の製造方法に関するものである。 The present invention relates to a method for producing a molded body, and more specifically, a molded body having fine irregularities on the surface thereof can be quickly, easily and reliably removed from a mold while maintaining the irregular shape well. The present invention relates to a method for producing a molded product that can be released into a mold.

現在、数十ｎｍから数百μｍの超微細な凹凸形状を表面に有するとともに、三次元、薄肉、かつ大面積の形状を有する成形体が、マイクロレンズ・アレイのような電子ディスプレイ用光学部品、マルチモード光導波路のような光情報通信用部品、マイクロ化学チップのようなライフサイエンス部品等として求められている。
一般にこのような成形体は、少なくとも一方の表面に微細な凹凸部を有する上金型および下金型を用い、この下金型上（もしくは下金型と上金型の間）に熱可塑性樹脂を設置し、金型を閉鎖させてプレスし、その後、得られた成形体を金型から離型することによって製造されている。
しかしながら、このようにして製造された表面に微細な凹凸形状を有する成形体は、金型と強固に付着し、離型が非常に困難であるという問題点を有する。 Currently, a molded article having an ultra-fine irregular shape of several tens of nm to several hundred μm on the surface, and a three-dimensional, thin, and large-area shape is an optical component for electronic displays such as a microlens array, There is a demand for optical information communication components such as multimode optical waveguides, life science components such as microchemical chips, and the like.
In general, such a molded body uses an upper mold and a lower mold having fine uneven portions on at least one surface, and a thermoplastic resin is formed on the lower mold (or between the lower mold and the upper mold). The mold is closed and pressed, and then the obtained molded body is released from the mold.
However, the molded body having a fine uneven shape on the surface thus produced has a problem that it adheres firmly to the mold and is very difficult to release.

特許文献１（特開２００２−５９４４０号公報）には、成形型より光学物品を離型するに際し、両者の接合部に局所的な温度差を与えて接合部を局所的に剥離し、該局所的な温度差による剥離域を順次拡大させて全域の離型を行う光学物品の製造方法および装置が開示されている。しかしこの技術は、成形型と光学物品の温度差によるソリを利用するため、光学物品が成形型から斜め方向に離型することになり、微細な凹凸形状が損傷するという問題点がある。とくにこの問題点は、微細な凹凸形状が円柱や角柱等の形状を有する場合に顕著であり、これにより微細な凹凸形状によっては適用できないものがある。また装置についても冷却用のエアー配管や押上部（機械式イジェクタ部）を設置する必要があり、装置構成が複雑になり、コストが増加するという問題点もある。
特許文献２（特開２００３−１５４５７３号公報）には、固定側金型と可動側金型とで形成される微細な凹凸を有するキャビティ内に成形原料を充填し、両金型を加熱し、両金型のいずれか一方もしくは両方に設けられた超音波振動子によって超音波振動させながら加圧、及び離型するエンボス加工成形方法および装置が開示されている。超音波振動子を使用することにより、成形体の離型は可能であるが、金型に超音波振動子を設置する必要があり、この場合も前記特許文献１と同様に装置構成が複雑になり、コストが増加するという問題点がある。また、超音波振動が原因で微細な凹凸が損傷する可能性がある。 In Patent Document 1 (Japanese Patent Application Laid-Open No. 2002-59440), when releasing an optical article from a mold, a local temperature difference is given to the joint between the two, and the joint is locally peeled off. A method and apparatus for manufacturing an optical article is disclosed in which a release region due to a typical temperature difference is sequentially expanded to release the entire region. However, since this technique uses a warp due to a temperature difference between the mold and the optical article, the optical article is released from the mold in an oblique direction, and there is a problem that a fine uneven shape is damaged. In particular, this problem is remarkable when the fine uneven shape has a shape such as a cylinder or a prism, and there are some cases in which the fine uneven shape cannot be applied. Further, it is necessary to install an air pipe for cooling and a push-up unit (mechanical ejector part) for the apparatus, and there is a problem that the apparatus configuration becomes complicated and the cost increases.
In Patent Document 2 (Japanese Patent Laid-Open No. 2003-154573), a molding material is filled in a cavity having fine irregularities formed by a fixed side mold and a movable side mold, and both molds are heated, There is disclosed an embossing molding method and apparatus for pressurizing and releasing while ultrasonically oscillating with an ultrasonic vibrator provided on one or both of both molds. Although it is possible to release the molded body by using the ultrasonic vibrator, it is necessary to install the ultrasonic vibrator in the mold, and in this case as well, the apparatus configuration is complicated as in Patent Document 1. Therefore, there is a problem that the cost increases. In addition, fine unevenness may be damaged due to ultrasonic vibration.

特開２００２−５９４４０号公報JP 2002-59440 A 特開２００３−１５４５７３号公報JP 2003-154573 A

したがって本発明の目的は、表面に微細な凹凸部を有する成形体を、その凹凸形状を良好に維持しながら、金型から迅速に、容易に、かつ確実に離型することのできる成形体の製造方法を提供することにある。 Accordingly, an object of the present invention is to provide a molded product that can be quickly and easily and reliably released from a mold while maintaining a good uneven shape on a molded product having fine irregularities on the surface. It is to provide a manufacturing method.

請求項１に記載の発明は、下記（１）〜（５）工程を順次有することを特徴とする成形体の製造方法である。
（１）一方の金型表面が鏡面を有し、他方の金型表面に微細な凹凸部を有する上金型および下金型を準備し、前記鏡面および微細な凹凸部を下記（２）工程で用いる熱可塑性樹脂のガラス転移温度±１０℃あるいはガラス転移温度以上に昇温する工程；
（２）前記微細な凹凸部上に熱可塑性樹脂の樹脂層を設ける工程；
（３）前記上金型および下金型を閉鎖し、両金型間に圧力を加え、前記樹脂層に前記微細な凹凸部の形状を転写し転写体を形成する工程；
（４）前記微細な凹凸部に前記転写体を付着させたまま、前記微細な凹凸部を前記熱可塑性樹脂のガラス転移温度以下に50℃／minの以上の冷却速度で、かつ前記鏡面の冷却速度に比べて25℃／min以上速い速度で冷却し、前記微細な凹凸部と前記転写体との付着力を低減させる工程；および
（５）前記鏡面に転写体を付着させながら、前記上金型および下金型を前記微細な凹凸部の面に対し垂直方向に開放し、前記転写体を前記微細な凹凸部から離型する工程。
請求項２に記載の発明は、前記（４）工程時、両金型の加熱を停止した後、前記鏡面を有する金型を放冷した状態で、前記微細な凹凸部を有する金型に30℃以下の冷却水を通水して冷却することを特徴とする請求項１に記載の成形体の製造方法である。
請求項３に記載の発明は、前記微細な凹凸部が、表面に微細な凹凸部を有するスタンパであることを特徴とする請求項１または２に記載の成形体の製造方法である。 The invention described in claim 1 is a method for producing a molded article, which has the following steps (1) to (5) in order.
(1) An upper mold and a lower mold having a mirror surface on one mold surface and a fine uneven portion on the other mold surface are prepared, and the mirror surface and the fine uneven portion are formed in the following step (2) The step of raising the glass transition temperature of the thermoplastic resin used in the step to ± 10 ° C. or higher than the glass transition temperature;
(2) The process of providing the resin layer of a thermoplastic resin on the said fine uneven part;
(3) closing the upper mold and the lower mold, applying pressure between both molds, and transferring the shape of the fine irregularities to the resin layer to form a transfer body;
(4) The mirror surface is cooled at a cooling rate of 50 ° C./min or more below the glass transition temperature of the thermoplastic resin while the transfer body is attached to the fine asperities. A step of cooling at a speed that is at least 25 ° C./min faster than the speed to reduce the adhesion between the fine irregularities and the transfer body; and (5) the upper metal while the transfer body is adhered to the mirror surface A step of opening the mold and the lower mold in a direction perpendicular to the surface of the fine uneven portion, and releasing the transfer body from the fine uneven portion.
According to the second aspect of the present invention, in the step (4), after the heating of both molds is stopped, the mold having the mirror surface is allowed to cool in the state where the mold having the mirror surface is allowed to cool. ℃ is a method for producing a molded article according to claim 1, characterized in that to be cool and passed through the following cooling water.
The invention according to claim 3, wherein the fine irregularities is a method for producing a molded article according to claim 1 or 2, characterized in that a stamper having a minute uneven portion on the surface.

本発明によれば、表面に微細な凹凸部を有する成形体を、その凹凸形状を良好に維持しながら、金型から迅速に、容易に、かつ確実に離型することのできる成形体の製造方法および装置を提供することができる。本発明は、成形体側の制約などにより離型剤などが使用できない場合に特に有効であるが、離型剤などを使用した場合には、さらに離型が容易となり、より大きな効果を得ることができる。 According to the present invention, it is possible to produce a molded body having a fine uneven portion on its surface, which can be quickly and easily and reliably released from the mold while maintaining its uneven shape. Methods and apparatus can be provided. The present invention is particularly effective when a mold release agent or the like cannot be used due to restrictions on the side of the molded article, but when a mold release agent or the like is used, mold release becomes easier and a greater effect can be obtained. it can.

以下、図面を参照しながら本発明の製造方法および金型装置をさらに詳細に説明する。
図１は本発明に使用できる金型装置の一実施形態の概略断面図である。
図１において、金型装置１は、対向して配置される一対の上金型１１および下金型１２を備えてなる。上金型１１および下金型１２は閉鎖してキャビティ面間に設置した樹脂層を加圧することが可能であり、可動金型としての上金型１１には、駆動手段としての加力発生器１３が設置されている。加力発生器１３は、上金型１１および下金型１２の型開閉と上金型１１および下金型１２のキャビティ面間の樹脂層の加圧を可能にするとともに、金型の精密な位置および速度制御機能を有する。
本発明では、一方の金型表面（図１の形態では上金型１１のキャビティ面）がＲａ２．０μｍ以下の鏡面１１１を有し、他方の金型表面（図１の形態では下金型１２のキャビティ面）が微細な凹凸部１２１を有する。
なお、本発明は上記形態に限定されない。前記微細な凹凸部を上金型に、前記鏡面を下金型に設けても良い。 Hereinafter, the manufacturing method and mold apparatus of the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a schematic sectional view of an embodiment of a mold apparatus that can be used in the present invention.
In FIG. 1, a mold apparatus 1 includes a pair of an upper mold 11 and a lower mold 12 that are arranged to face each other. The upper die 11 and the lower die 12 can be closed to pressurize the resin layer placed between the cavity surfaces, and the upper die 11 as a movable die has a force generator as a driving means. 13 is installed. The force generator 13 enables the mold opening and closing of the upper mold 11 and the lower mold 12 and pressurization of the resin layer between the cavity surfaces of the upper mold 11 and the lower mold 12, and the precision of the mold. Has position and speed control function.
In the present invention, one mold surface (the cavity surface of the upper mold 11 in the form of FIG. 1) has a mirror surface 111 of Ra 2.0 μm or less, and the other mold surface (the lower mold 12 in the form of FIG. 1). The cavity surface) has fine uneven portions 121.
In addition, this invention is not limited to the said form. You may provide the said fine uneven | corrugated | grooved part in an upper metal mold | die, and the said mirror surface in a lower metal mold | die.

本明細書でいうＲａとは、ＪＩＳＢ０６０１−１９９４に規定された算術平均粗さを意味する。鏡面１１１のＲａは、２．０μｍ以下が好ましく、０．２μｍ以下がさらに好ましい。
下金型１２は、微細な凹凸部１２１を有する。微細な凹凸部１２１は、例えば１０ｎｍ〜１ｍｍの幅または直径を有するとともに、１０ｎｍ〜１ｍｍの深さまたは高さを有する。
また、上金型１１には、図１に示したように、加熱手段と、冷却手段を設置するのが好ましい。なお本形態では、下金型１２にも加熱手段および冷却手段が設けられている。加熱手段は、例えば加熱ヒータ１５から構成され、冷却手段は、冷却水が流れる冷却管１６から構成されている。また、上金型１１および下金型１２には、図示しない温度センサおよび温度制御手段が設けられ、これらにより両金型の温度制御が可能となっている。なお上金型１１および下金型１２の温度制御は、ＰＩＤ制御などにより行うことができる。上記温度制御手段は、上金型１１と下金型１２で別々に備えることが望ましく、加熱速度、冷却速度の調節を行えることがさらに望ましい。加熱速度の制御は前記ＰＩＤ制御などにより、冷却速度の制御は冷却水量調節、冷却媒体の温度調節などにより容易に行うことができる。また、図１の形態では、下金型１２に直接微細な凹凸部１２１が設けられているが、これとは別に、表面に微細な凹凸部を有するスタンパーを下金型１２上に設置してもよい。スタンパーを用いる場合は、下金型１２に該スタンパーを固定する手段を設けるのが好ましい。 Ra as used in this specification means the arithmetic mean roughness specified in JIS B0601-1994. Ra of the mirror surface 111 is preferably 2.0 μm or less, and more preferably 0.2 μm or less.
The lower mold 12 has fine uneven portions 121. The fine uneven portion 121 has, for example, a width or diameter of 10 nm to 1 mm and a depth or height of 10 nm to 1 mm.
Further, as shown in FIG. 1, it is preferable that the upper mold 11 is provided with heating means and cooling means. In this embodiment, the lower mold 12 is also provided with heating means and cooling means. The heating means is constituted by a heater 15, for example, and the cooling means is constituted by a cooling pipe 16 through which cooling water flows. Further, the upper mold 11 and the lower mold 12 are provided with a temperature sensor and a temperature control means (not shown), thereby enabling temperature control of both molds. The temperature control of the upper mold 11 and the lower mold 12 can be performed by PID control or the like. The temperature control means is desirably provided separately for the upper mold 11 and the lower mold 12, and more preferably capable of adjusting the heating rate and the cooling rate. The heating rate can be easily controlled by the PID control, and the cooling rate can be easily controlled by adjusting the amount of cooling water, adjusting the temperature of the cooling medium, and the like. Further, in the form of FIG. 1, the fine uneven portion 121 is directly provided on the lower mold 12, but separately from this, a stamper having fine uneven portions on the surface is installed on the lower mold 12. Also good. When using a stamper, it is preferable to provide means for fixing the stamper to the lower mold 12.

本発明の（１）工程は、鏡面１１１および微細な凹凸部１２１を下記（２）工程で用いる熱可塑性樹脂のガラス転移温度付近あるいはガラス転移温度以上に昇温する工程である。
鏡面１１１および微細な凹凸部１２１の昇温は、上金型１１および下金型１２の加熱ヒータ１５の稼動により可能である。
本発明では、熱可塑性樹脂のガラス転移温度よりも１０℃以上高い温度に鏡面１１１および微細な凹凸部１２１を昇温させるのが好ましい。
また、本発明でいうガラス転移温度付近とは、ガラス転移温度±１０℃の範囲である。 The step (1) of the present invention is a step of raising the temperature of the mirror surface 111 and the fine irregularities 121 to near or above the glass transition temperature of the thermoplastic resin used in the following step (2).
The mirror surface 111 and the fine uneven portion 121 can be heated by operating the heaters 15 of the upper mold 11 and the lower mold 12.
In the present invention, it is preferable to raise the temperature of the mirror surface 111 and the fine irregularities 121 to a temperature that is 10 ° C. or more higher than the glass transition temperature of the thermoplastic resin.
Further, the vicinity of the glass transition temperature in the present invention means a range of glass transition temperature ± 10 ° C.

図２は、本発明の製造方法の（２）工程、すなわち微細な凹凸部１２１上または鏡面１１１上に樹脂層を設ける工程を説明するための図である。なお本形態では微細な凹凸部１２１上に樹脂層を設けている。
図２において、下金型１２上の微細な凹凸部１２１上に、樹脂層２１が形成される。樹脂層２１の形成方法はとくに制限されないが、吐出口２２を備えた塗布装置２３に熱可塑性樹脂を供給し、塗布装置２３を矢印２４方向に移動させながら、微細な凹凸部１２１の上方から熱可塑性樹脂を吐出し、微細な凹凸部１２１上に熱可塑性樹脂を設置するのが好ましい。このようにすれば、高い寸法精度、低残留応力、低複屈折、高光透過性、優れた機械的強度を有する成形体を、超低圧の成形プロセスでありながら、三次元、薄肉、かつ大面積の形状でもって提供することができる。熱可塑性樹脂としてはとくに制限されないが、例えばポリメチルメタクリレート樹脂(PMMA)、ポリカーボネート(PC)、シクロオレフィン(COP)、ポリエチレンテレフタレート(PET)、ポリエチレンナフタレート（PEN)、ポリブチレンテレフタレート(PBT)、ポリアリレート(PAR)、ポリイミド(PI)、ポリスチレン(PS)、ポリプロピレン(PP)、ポリアミド(PA)、ポリエチレン(PE)、ポリアセタール(POM)、エチレン-酢酸ビニル共重合樹脂(EVA)、アクリロニトリルブタジエンスチレン(ABS)、メチルメタクリレートブタジエンスチレン（MBS)、ポリ塩化ビニル(PVC)、ポリフェニレンオキサイド(PPO)またはこれらの混合物などが挙げられる。また、成形体に求められる性能にあわせて、特別に製造された熱可塑性樹脂でもよい。なお、熱可塑性樹脂の吐出以外にも、熱可塑性樹脂フィルムもしくは樹脂製の板材を微細な凹凸部１２１上に設置してもよい。 FIG. 2 is a diagram for explaining the step (2) of the manufacturing method of the present invention, that is, the step of providing a resin layer on the fine irregularities 121 or the mirror surface 111. In this embodiment, a resin layer is provided on the fine uneven portion 121.
In FIG. 2, the resin layer 21 is formed on the fine uneven portion 121 on the lower mold 12. The method for forming the resin layer 21 is not particularly limited, but the thermoplastic resin is supplied to the coating device 23 provided with the discharge ports 22, and the coating device 23 is moved in the direction of the arrow 24 while the heat is applied from above the fine uneven portion 121. It is preferable to discharge the plastic resin and install the thermoplastic resin on the fine uneven portion 121. In this way, a molded body having high dimensional accuracy, low residual stress, low birefringence, high light transmittance, and excellent mechanical strength can be formed into a three-dimensional, thin-walled, large-area area while being an ultra-low pressure molding process. Can be provided in the form of Although not particularly limited as the thermoplastic resin, for example, polymethyl methacrylate resin (PMMA), polycarbonate (PC), cycloolefin (COP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), Polyarylate (PAR), polyimide (PI), polystyrene (PS), polypropylene (PP), polyamide (PA), polyethylene (PE), polyacetal (POM), ethylene-vinyl acetate copolymer resin (EVA), acrylonitrile butadiene styrene (ABS), methyl methacrylate butadiene styrene (MBS), polyvinyl chloride (PVC), polyphenylene oxide (PPO), or a mixture thereof. Further, a thermoplastic resin specially manufactured in accordance with the performance required for the molded body may be used. In addition to the discharge of the thermoplastic resin, a thermoplastic resin film or a resin plate material may be provided on the fine uneven portion 121.

本発明の（３）工程は、上金型１１および下金型１２を閉鎖し、両金型間に圧力を加え、樹脂層２１に微細な凹凸部１２１の形状を転写し転写体を形成する工程である（図３）。両金型間の加圧は、加力発生器１３によって行う。前述のように、加力発生器１３は、上金型１１および下金型１２の型開閉と上金型１１および下金型１２のキャビティ面間の樹脂層の加圧を可能にするとともに、金型の精密な位置および速度制御機能を有する。両金型間の圧力は、例えば１〜１０ＭＰａである。 In the step (3) of the present invention, the upper mold 11 and the lower mold 12 are closed, pressure is applied between both molds, and the shape of the fine uneven portion 121 is transferred to the resin layer 21 to form a transfer body. It is a process (FIG. 3). Pressurization between both molds is performed by the force generator 13. As described above, the force generator 13 enables opening and closing of the upper mold 11 and the lower mold 12 and pressurization of the resin layer between the cavity surfaces of the upper mold 11 and the lower mold 12. Has precise position and speed control function of the mold. The pressure between both molds is, for example, 1 to 10 MPa.

本発明の（４）工程は、微細な凹凸部１２１に転写体を付着させたまま、微細な凹凸部１２１を熱可塑性樹脂のガラス転移温度以下に急速に冷却し、微細な凹凸部１２１と転写体との付着力を低減させる工程である。
この（４）工程では、樹脂層２１を冷却固化する際に、微細な凹凸部１２１を有する下金型１２を急速に冷却し、上金型１１に比べて冷却速度を速くすることがより望ましい。この方法は、微細な凹凸部と転写体との付着力が非常に高い場合にとくに有効である。
ここで本発明者らの検討によれば、熱可塑性樹脂は、付着面との付着力に温度依存性が存在し、そのガラス転移温度（Ｔｇ）付近で金属やガラス等の無機質板に最も付着力が増大し、Ｔｇ以下では急速に付着力が低下することが判明した。
図４は、鏡面１１１の温度に対する、ポリスチレン(PS)の付着力（引き剥がし力）の関係を説明するための図である。
図４によれば、鏡面１１１の温度を上昇させるにしたがって、ポリスチレンの引き剥がし力も上昇し、ポリスチレンのＴｇ（約１００℃）で引き剥がし力が最大となっている。なお図４では鏡面１１１の材質としてソーダガラス（四角形のプロット）と石英ガラス（三角形のプロット）を使用した例であるが、本発明者らは金型を通常構成する材質においても同様の結果が得られることを確認している。
したがって、（４）工程時に下金型１２の微細な凹凸部１２１を熱可塑性樹脂のガラス転移温度以下に急速に冷却することにより、微細な凹凸部１２１と樹脂層２１との付着力を低減させ、微細な凹凸部１２１から樹脂層２１を離型しやすい状態とすることができる。 In the step (4) of the present invention, the fine irregularities 121 are rapidly cooled below the glass transition temperature of the thermoplastic resin while the transfer body is adhered to the fine irregularities 121, and the fine irregularities 121 and the transfer are transferred. This is a step of reducing the adhesion force with the body.
In this step (4), when the resin layer 21 is cooled and solidified, it is more desirable to rapidly cool the lower mold 12 having the fine irregularities 121 and to increase the cooling rate compared to the upper mold 11. . This method is particularly effective when the adhesion between the fine irregularities and the transfer body is very high.
Here, according to the study by the present inventors, the thermoplastic resin has temperature dependence on the adhesion force with the adhesion surface, and is most attached to an inorganic plate such as metal or glass near its glass transition temperature (Tg). It was found that the adhesion was increased and the adhesion was rapidly reduced below Tg.
FIG. 4 is a diagram for explaining the relationship of the adhesion force (peeling force) of polystyrene (PS) to the temperature of the mirror surface 111.
According to FIG. 4, as the temperature of the mirror surface 111 is increased, the peeling force of polystyrene is also increased, and the peeling force is maximized at the Tg of polystyrene (about 100 ° C.). FIG. 4 shows an example in which soda glass (rectangular plot) and quartz glass (triangular plot) are used as the material of the mirror surface 111, but the present inventors have obtained the same result even in the material that normally constitutes the mold. It is confirmed that it can be obtained.
Therefore, the adhesive force between the fine irregularities 121 and the resin layer 21 is reduced by rapidly cooling the fine irregularities 121 of the lower mold 12 to the glass transition temperature or lower of the thermoplastic resin during the step (4). Thus, the resin layer 21 can be easily released from the fine irregularities 121.

また、下金型１２を急速に冷却することにより、下金型１２と樹脂層２１との収縮が生じるが、この際、金型と樹脂との線膨張率の差に起因するズリ変形が生じ、微細な凹凸部１２１と樹脂層２１との付着力がさらに低下する。
図５は、微細な凹凸部１２１に充填された樹脂層２１の体積収縮およびズリ変形を説明するための、微細な凹凸部１２１と樹脂層２１の拡大断面図である。
図５（ａ）のように、微細な凹凸部１２１に熱可塑性樹脂からなる樹脂層２１が充填され、続いて矢印４１方向のプレス力を印加したまま樹脂層２１を冷却し固化させると、図５（ｂ）に示すように樹脂層２１が微細な凹凸部１２１の内側方向（矢印４２方向）に向かって体積収縮が生じる。同時に、下金型１２の金属と樹脂層２１の界面で両者の線膨張率の差による相対的なズリ変形が、矢印４３方向で生じる。同時に、樹脂層２１と微細な凹凸部１２１との間に間隙が生じ、樹脂層２１と微細な凹凸部１２１との間の真空が破壊される。これらの理由から、調製された転写体が微細な凹凸部１２１から離型しやすくなる。
一方、上金型１１の鏡面１１１と樹脂層２１との間は、加圧により樹脂層２１が外側方向に変形しても、冷却による体積収縮により内側方向に変形しても、上金型１１の鏡面１１１と樹脂層２１との間に真空状態は維持される。したがって、上金型１１の鏡面１１１と転写体との付着力が、微細な凹凸部１２１と転写体との付着力よりも大きい場合は、上金型１１および下金型１２を微細な凹凸部１２１の面に対し垂直方向に開放すれば、微細な凹凸部１２１と転写体とが接触することなく、転写体は上金型１１の鏡面１１１に付着したまま微細な凹凸部１２１から離型される。 Further, when the lower mold 12 is rapidly cooled, shrinkage between the lower mold 12 and the resin layer 21 occurs. At this time, shear deformation due to a difference in linear expansion coefficient between the mold and the resin occurs. Further, the adhesive force between the fine uneven portion 121 and the resin layer 21 is further reduced.
FIG. 5 is an enlarged cross-sectional view of the fine concavo-convex portion 121 and the resin layer 21 for explaining volume shrinkage and shear deformation of the resin layer 21 filled in the fine concavo-convex portion 121.
As shown in FIG. 5A, when the resin layer 21 made of a thermoplastic resin is filled in the fine concavo-convex portion 121, and then the resin layer 21 is cooled and solidified while the pressing force in the direction of the arrow 41 is applied, As shown in FIG. 5 (b), the resin layer 21 shrinks in volume toward the inner side (arrow 42 direction) of the fine uneven portion 121. At the same time, relative slip deformation due to the difference in linear expansion coefficient between the metal of the lower mold 12 and the resin layer 21 occurs in the direction of the arrow 43. At the same time, a gap is generated between the resin layer 21 and the fine uneven portion 121, and the vacuum between the resin layer 21 and the fine uneven portion 121 is broken. For these reasons, the prepared transfer body is easily released from the fine uneven portion 121.
On the other hand, between the mirror surface 111 of the upper mold 11 and the resin layer 21, even if the resin layer 21 is deformed outward due to pressurization or is deformed inward due to volume contraction due to cooling, the upper mold 11. A vacuum state is maintained between the mirror surface 111 and the resin layer 21. Therefore, when the adhesive force between the mirror surface 111 of the upper mold 11 and the transfer body is larger than the adhesive force between the fine uneven portion 121 and the transfer body, the upper mold 11 and the lower mold 12 are made to be fine uneven portions. If it is opened in a direction perpendicular to the surface of 121, the fine uneven portion 121 and the transfer body do not come into contact with each other, and the transfer body is released from the fine uneven portion 121 while adhering to the mirror surface 111 of the upper mold 11. The

上記下金型１２の急速な冷却にともなう微細な凹凸部１２１と樹脂層２１との付着力の低減および金型と樹脂との間の線膨張率の差に起因するズリ変形による微細な凹凸部１２１と樹脂層２１との付着力の低下により、本発明の（５）工程において、上金型１１を微細な凹凸部１２１に対して垂直方向に開放すれば、図６に示したように、上金型１１の鏡面１１１に樹脂層２１を付着させたまま転写体５１を下金型１２の微細な凹凸部１２１から離型することができる。 Fine irregularities due to reduction in adhesion between the fine irregularities 121 and the resin layer 21 due to rapid cooling of the lower mold 12 and slip deformation due to the difference in linear expansion coefficient between the mold and the resin If the upper mold 11 is opened in the vertical direction with respect to the fine irregularities 121 in the step (5) of the present invention due to a decrease in adhesion between the resin 121 and the resin layer 21, as shown in FIG. The transfer body 51 can be released from the fine irregularities 121 of the lower mold 12 while the resin layer 21 is adhered to the mirror surface 111 of the upper mold 11.

前記急速な冷却は、使用する樹脂、加圧時の金型温度、加圧力などにも影響されるが、例えば、アクリル樹脂で加圧時の金型温度を110〜150℃、加圧力を5〜10M Paとした場合、下金型１２の微細な凹凸部１２１の冷却速度を少なくとも冷却初期の10秒間は50℃／min以上、より好ましくは100℃／min以上とし、上金型１１の鏡面１１１の冷却速度を下金型１２より遅くすることで効果を一層良好に得ることができる。なお上記冷却速度は、アクリル樹脂以外の熱可塑性樹脂を使用した場合でも適用できる。
また急速な冷却は少なくとも上金型１１の金型温度が樹脂のガラス転移温度付近になるまで続けるのが好ましい。 The rapid cooling is affected by the resin used, the mold temperature during pressurization, and the applied pressure. For example, the mold temperature during pressurization with acrylic resin is 110 to 150 ° C., and the applied pressure is 5 In the case of ˜10 MPa, the cooling rate of the fine uneven portion 121 of the lower mold 12 is set to 50 ° C./min or more, more preferably 100 ° C./min or more for at least the first 10 seconds of cooling, and the mirror surface of the upper mold 11 By making the cooling rate of 111 slower than that of the lower mold 12, the effect can be further improved. In addition, the said cooling rate is applicable even when using thermoplastic resins other than an acrylic resin.
The rapid cooling is preferably continued until at least the mold temperature of the upper mold 11 is close to the glass transition temperature of the resin.

前記微細な凹凸部１２１を有する下金型１２を急速に冷却する方法としては、下金型１２の容積を小さくし、熱容量を小さくした状態で冷却水を通水する、あるいは、下金型１２の微細な凹凸部１２１の表面近傍に設けた冷却管１６に低温の媒体（好ましくは３０℃以下の冷却水）を流すことなどが挙げられる。
また、下金型１２を上金型１１に比べて速く冷却する方法としては、例えば、下金型１２の微細な凹凸部１２１と冷却管１６との距離を、上金型１１の鏡面１１１と冷却管１６との距離に比べて短くする；下金型１２の冷却管１６の直径を上金型１１に比べて大きくして媒体の流量を大きくする；下金型１２の冷却管１６に流れる媒体の温度を上金型１１に比べて低くするなどが挙げられる。また、前記以外にも、下金型１２と上金型１１とで温度の異なる媒体を流して、下金型１２の冷却管１６に流す媒体の温度を上金型１１に比べて低くするなどしてもよい。 As a method of rapidly cooling the lower mold 12 having the fine irregularities 121, the volume of the lower mold 12 is reduced and cooling water is passed in a state where the heat capacity is reduced, or the lower mold 12 For example, a low-temperature medium (preferably cooling water of 30 ° C. or lower) is allowed to flow through the cooling pipe 16 provided in the vicinity of the surface of the fine uneven portion 121.
Further, as a method for cooling the lower mold 12 faster than the upper mold 11, for example, the distance between the fine uneven portion 121 of the lower mold 12 and the cooling pipe 16 is set to the mirror surface 111 of the upper mold 11. Shorter than the distance to the cooling pipe 16; the diameter of the cooling pipe 16 of the lower mold 12 is made larger than that of the upper mold 11 to increase the flow rate of the medium; it flows to the cooling pipe 16 of the lower mold 12 For example, the temperature of the medium is made lower than that of the upper mold 11. In addition to the above, a medium having different temperatures is flowed between the lower mold 12 and the upper mold 11 so that the temperature of the medium flowing through the cooling pipe 16 of the lower mold 12 is lower than that of the upper mold 11. May be.

また、本発明によれば、前述のように、前記（４）工程において、樹脂層２１を冷却固化する際に、微細な凹凸部１２１を有する下金型１２を急速に冷却し、上金型１１をゆっくり冷却することが望ましい。
前記方法は、微細な凹凸部と転写体との付着力が非常に高い場合にとくに有効である。
このような場合、閉鎖した金型内において、金型の冷却中に次の現象が生じる。すなわち、上金型１１の鏡面１１１から下金型１２の微細な凹凸部１２１への熱の移動、微細な凹凸部１２１と樹脂層２１との間の付着力の低下、冷却による樹脂層及び金型の収縮、鏡面１１１と微細な凹凸部１２１との間の温度差の形成である。 Further, according to the present invention, as described above, in the step (4), when the resin layer 21 is cooled and solidified, the lower mold 12 having the fine irregularities 121 is rapidly cooled, and the upper mold It is desirable to cool 11 slowly.
The method is particularly effective when the adhesion between the fine irregularities and the transfer body is very high.
In such a case, the following phenomenon occurs during mold cooling in the closed mold. That is, heat transfer from the mirror surface 111 of the upper mold 11 to the fine irregularities 121 of the lower mold 12, a decrease in adhesion between the fine irregularities 121 and the resin layer 21, a resin layer and a mold due to cooling Shrinkage of the mold and formation of a temperature difference between the mirror surface 111 and the fine uneven portion 121.

まず、下金型１２の冷却管１６に低温の媒体、例えば冷却水を通水することにより、下金型１２の微細な凹凸部１２１の温度は急速に低下する。一方、上金型１１に冷却水を流さないことにより、上金型１１の鏡面１１１の温度は高い状態にある。その結果、下金型１２の微細な凹凸部１２１と上金型１１の鏡面１１１との間の温度勾配が大きくなり、図７に示すように、上金型１１の鏡面１１１から下金型１２の微細な凹凸部１２１への熱の流れが生じる。
一方、鏡面１１１と微細な凹凸部１２１との間の樹脂層２１は、金属に比べて熱伝導率が低く、一種の断熱層として作用するため、微細な凹凸部１２１の冷却速度は鏡面１１１の冷却速度に比べ高い状態で維持され、下金型１２の微細な凹凸部１２１が選択的に冷却されることになる。そのため、下金型１２を樹脂のガラス転移温度以下まで冷却すれば、低温の下金型１２の微細な凹凸部１２１と樹脂層２１との付着力が選択的に低下し、高温の上金型１１の鏡面１１１に樹脂層２１が付着しやすい状況が形成される。
この際、下金型１２の微細な凹凸部１２１では冷却により樹脂層２１および下金型１２の収縮が生じるが、双方の線膨張率が異なるため、微細な凹凸部１２１に対して垂直方向では相対的なズリ変形が生じ、微細な凹凸部１２１と樹脂層２１との付着力が低減される。また、微細な凹凸部１２１に対して垂直方向および水平方向では樹脂層２１と微細な凹凸部１２１との間に微小な間隙が生じる。一方、樹脂層２１が垂直方向および水平方向に収縮して間隙が生じた部分は、樹脂層２１と金型との接触面積が低下するため、熱がさらに伝播しにくくなり、樹脂層２１と微細な凹凸部１２１が接触している部分のみが選択的に冷却される。そのため、樹脂層２１と微細な凹凸部１２１が接触している部分でのみ収縮が進行し、微小な間隙が形成され、微細な凹凸部１２１の全面で均一に樹脂層２１が剥離されやすくなる。一方、樹脂および金型が収縮しても鏡面１１１と樹脂層２１との間には間隙が生じないため、樹脂層２１との接触面積が維持され、鏡面１１１と樹脂層２１との付着力が相対的に増加する。
冷却中に上記の現象が同時進行で生じた結果、上金型１１と樹脂層２１との付着力が強い状態で維持され、下金型１２と樹脂層２１との付着力は微細な凹凸部１２１の全面で均一に低減されるため、樹脂層２１が上金型１１に付着した状態となる。
この状態で上金型１１を微細な凹凸部１２１に対して垂直方向に開放すれば、図６に示したように、上金型１１に転写体５１を付着させたまま転写体５１を微細な凹凸部１２１から離型することができる。 First, by passing a low-temperature medium such as cooling water through the cooling pipe 16 of the lower mold 12, the temperature of the fine irregularities 121 of the lower mold 12 rapidly decreases. On the other hand, the temperature of the mirror surface 111 of the upper mold 11 is in a high state by not flowing cooling water through the upper mold 11. As a result, the temperature gradient between the fine irregularities 121 of the lower mold 12 and the mirror surface 111 of the upper mold 11 increases, and the lower mold 12 extends from the mirror surface 111 of the upper mold 11 as shown in FIG. The heat flow to the fine irregularities 121 is generated.
On the other hand, the resin layer 21 between the mirror surface 111 and the fine irregularities 121 has a lower thermal conductivity than metal, and acts as a kind of heat insulating layer. It is maintained in a state higher than the cooling rate, and the fine uneven portion 121 of the lower mold 12 is selectively cooled. Therefore, if the lower mold 12 is cooled to below the glass transition temperature of the resin, the adhesive force between the fine irregularities 121 of the low temperature lower mold 12 and the resin layer 21 is selectively reduced, and the high temperature upper mold is reduced. Thus, the resin layer 21 is likely to adhere to the eleven mirror surfaces 111.
At this time, although the resin layer 21 and the lower mold 12 are contracted by cooling in the fine uneven portion 121 of the lower mold 12, since the linear expansion coefficients of both are different, in the direction perpendicular to the fine uneven portion 121. Relative shear deformation occurs, and the adhesive force between the fine uneven portion 121 and the resin layer 21 is reduced. In addition, a minute gap is generated between the resin layer 21 and the minute irregularities 121 in the vertical and horizontal directions with respect to the minute irregularities 121. On the other hand, in the portion where the resin layer 21 contracts in the vertical direction and the horizontal direction and the gap is generated, the contact area between the resin layer 21 and the mold is reduced, so that heat is more difficult to propagate, and the resin layer 21 and the resin layer 21 are fine. Only the portion where the uneven portion 121 is in contact is selectively cooled. Therefore, the shrinkage proceeds only at the portion where the resin layer 21 and the fine uneven portion 121 are in contact with each other, a minute gap is formed, and the resin layer 21 is easily peeled uniformly over the entire surface of the fine uneven portion 121. On the other hand, even if the resin and the mold are contracted, no gap is generated between the mirror surface 111 and the resin layer 21, so that the contact area with the resin layer 21 is maintained, and the adhesion between the mirror surface 111 and the resin layer 21 is increased. Increase relatively.
As a result of the above phenomenon occurring simultaneously during cooling, the adhesion between the upper mold 11 and the resin layer 21 is maintained in a strong state, and the adhesion between the lower mold 12 and the resin layer 21 is a fine uneven portion. Since the surface area 121 is uniformly reduced, the resin layer 21 is attached to the upper mold 11.
If the upper mold 11 is opened in the vertical direction with respect to the fine irregularities 121 in this state, the transfer body 51 is made fine with the transfer body 51 attached to the upper mold 11 as shown in FIG. The mold can be released from the uneven portion 121.

前記離型は、使用する樹脂、加圧時の金型温度、加圧力などにも影響されるが、例えば、アクリル樹脂で加圧時の金型温度を110〜150℃、加圧力を5〜10M Paとした場合で、下金型１２の微細な凹凸部１２１の冷却速度を50℃／min以上とし、上金型１１の鏡面１１１の冷却速度よりも25℃／min以上速くすることで顕著な効果を得ることができる。
なお上記冷却速度の差は、アクリル樹脂以外の熱可塑性樹脂を使用した場合でも適用できる。 The mold release is also affected by the resin used, the mold temperature during pressurization, the applied pressure, etc., for example, the mold temperature during pressurization with an acrylic resin is 110-150 ° C., the applied pressure is 5-5 When the pressure is 10 MPa, the cooling rate of the fine uneven portion 121 of the lower mold 12 is set to 50 ° C./min or more, and is significantly increased by 25 ° C./min or more faster than the cooling rate of the mirror surface 111 of the upper mold 11. Effects can be obtained.
The difference in cooling rate can be applied even when a thermoplastic resin other than an acrylic resin is used.

このような下金型１２と上金型１１とで冷却速度の差を形成する方法としては、例えば、下金型１２の冷却管１６にのみ冷却水を通水し、上金型はヒータをOFFにした状態で放冷あるいは空冷するなどが挙げられる。 As a method of forming a difference in cooling rate between the lower mold 12 and the upper mold 11, for example, cooling water is passed only to the cooling pipe 16 of the lower mold 12, and the upper mold has a heater. For example, it is allowed to cool or air cool in the OFF state.

また、本発明によれば、前記（４）工程時、両金型間の加圧を停止した後、微細な凹凸部１２１と鏡面１１１との間隔を樹脂層２１の厚み±5％以内の距離に保持した状態（以下、位置保持という）で、上金型１１および下金型１２を冷却することが好ましい。
前記方法は微細な凹凸部と転写体との付着力が強い場合に特に有効である。
上記形態では、冷却による樹脂層２１および金型の収縮により、微細な凹凸部１２１と樹脂層２１との界面Ｂ（凹部）のみでなく、界面Ａ（凸部）においても樹脂層２１の微細な凹凸部１２１からの剥離が進行し、より一層離型が容易となる。樹脂層２１の冷却工程において、加圧力を維持した状態では、図８（ａ）に示すように、冷却による樹脂および金型の収縮により、微細な凹凸部１２１と樹脂層２１との界面Ｂのみで剥離が進行し、界面Ａは加圧力により接触が維持される。これに対し、図８（ｂ）に示すように、加圧を停止し、上金型１１の鏡面１１１と下金型１２の微細な凹凸部１２１との間隔Ｃを、樹脂層２１の厚みと同じ距離、すなわち樹脂層２１の厚み±5％以内の距離に保った場合、樹脂層２１の収縮により、界面Ａにおいても空間が形成される。この時、図５に示したように、上金型１１の鏡面１１１と樹脂層２１との界面は付着した状態を維持するため、上金型１１の鏡面１１１と樹脂層２１との付着力が相対的に高くなり、下金型１２の微細な凹凸部１２１から剥離を補助する。また、界面Ａおよび界面Ｂにおける微細な凹凸部１２１と樹脂層２１との剥離は、樹脂の収縮により進展するため、徐々に進行していくが、先に微細な凹凸部１２１から剥離された部分は熱が伝わりにくくなるため、微細な凹凸部と接触している部分のみが選択的に冷却され、収縮し、微細な凹凸部１２１の全面で均一に樹脂層２１の剥離が進行する。上記により、冷却工程において微細な凹凸部１２１と樹脂層２１との付着力が大きく低減されるため、冷却工程の後、金型を開放する際に微細な凹凸部１２１から転写体を離型することが一層容易となる。
加圧から位置保持に移行するタイミングについては特に指定はないが、加圧時の金型温度が高い場合は、冷却と同時に位置保持に移行すると、樹脂が固化するまでの温度差が大きいため、冷却による樹脂の収縮によってヒケなどの外観不良が発生する可能性がある。このような場合、冷却管１６に冷却水を通水して、両金型の温度がある程度降下するまで加圧力を維持した後、位置保持に移行するのが望ましい。 Further, according to the present invention, in the step (4), after the pressurization between both molds is stopped, the distance between the fine uneven portion 121 and the mirror surface 111 is a distance within ± 5% of the thickness of the resin layer 21. It is preferable to cool the upper mold 11 and the lower mold 12 in a state where the upper mold 11 and the lower mold 12 are held.
This method is particularly effective when the adhesion between the fine irregularities and the transfer body is strong.
In the above embodiment, the resin layer 21 and the mold are shrunk by cooling, so that the resin layer 21 is fine not only at the interface B (concave portion) between the fine uneven portion 121 and the resin layer 21 but also at the interface A (convex portion). Peeling from the concavo-convex portion 121 proceeds, and release becomes easier. In the cooling process of the resin layer 21, only the interface B between the fine concavo-convex portion 121 and the resin layer 21 is caused by the shrinkage of the resin and the mold due to the cooling as shown in FIG. Peeling progresses and the interface A is maintained in contact with the applied pressure. On the other hand, as shown in FIG. 8 (b), the pressurization is stopped, and the distance C between the mirror surface 111 of the upper mold 11 and the fine irregularities 121 of the lower mold 12 is set to the thickness of the resin layer 21. When the distance is kept within the same distance, that is, a distance within ± 5% of the resin layer 21, a space is also formed at the interface A due to the shrinkage of the resin layer 21. At this time, as shown in FIG. 5, the interface between the mirror surface 111 of the upper mold 11 and the resin layer 21 is maintained in an attached state, so that the adhesion between the mirror surface 111 of the upper mold 11 and the resin layer 21 is increased. It becomes relatively high and assists peeling from the fine uneven portion 121 of the lower mold 12. In addition, the separation between the fine uneven portion 121 and the resin layer 21 at the interface A and the interface B progresses gradually due to the shrinkage of the resin, but the portion that has been peeled off from the fine uneven portion 121 first. Therefore, only the portion in contact with the fine uneven portion is selectively cooled and contracted, and the resin layer 21 is peeled uniformly over the entire surface of the fine uneven portion 121. As described above, the adhesive force between the fine irregularities 121 and the resin layer 21 is greatly reduced in the cooling process, and therefore, the transfer body is released from the fine irregularities 121 when the mold is opened after the cooling process. It becomes easier.
There is no specific timing for the transition from pressurization to position holding, but if the mold temperature during pressurization is high, there is a large temperature difference until the resin solidifies when shifting to position holding simultaneously with cooling. There is a possibility that appearance defects such as sink marks may occur due to the shrinkage of the resin due to cooling. In such a case, it is desirable to pass cooling water through the cooling pipe 16 and maintain the applied pressure until the temperatures of both molds drop to some extent, and then shift to position holding.

なお、本発明は上記形態に限定されない。例えば、下金型１２の微細な凹凸部１２１以外の部分と上金型１１の鏡面１１１以外の部分との距離を一定に保っても良いし（例えば図８（ｂ）における距離Ｄ）、金型の位置をプレスの型盤位置により制御する場合は、プレスの盤面間の距離を一定に保ってもよい。その場合、上金型１１の鏡面１１１と微細な凹凸部１２１が接触する位置より、樹脂層の厚みだけ金型が開放された状態で金型の位置を保持すれば、前記と同様の効果を得ることができる。さらに、金型盤面がモータで駆動する場合は、加圧後、冷却中にモータの回転を停止するだけでも同様の効果を得ることができる。 In addition, this invention is not limited to the said form. For example, the distance between the portion other than the fine uneven portion 121 of the lower mold 12 and the portion other than the mirror surface 111 of the upper mold 11 may be kept constant (for example, the distance D in FIG. 8B), When the mold position is controlled by the press platen position, the distance between the press platen surfaces may be kept constant. In that case, if the position of the mold is held in a state where the mold is opened by the thickness of the resin layer from the position where the mirror surface 111 of the upper mold 11 and the fine uneven portion 121 are in contact, the same effect as described above can be obtained. Obtainable. Furthermore, when the mold platen surface is driven by a motor, the same effect can be obtained simply by stopping the rotation of the motor during cooling after pressurization.

以下、本発明を実施例によってさらに説明するが、本発明は下記例に限定されるものではない。 EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to the following example.

実施例１
実施例１は、図１に示す装置を用いて実施した。
加熱ヒータ１５を稼動して下金型１２を１４０℃に、上金型１１を１４０℃に加熱した後、アクリル樹脂を、２３５℃に加熱して溶融し、縦、横、深さ、凹凸部の間隔がいずれも５０μｍであるＮｉ製スタンパーの微細な凹凸部１２１上に、塗布厚さ１３０μｍとして塗布装置により塗布し、樹脂層２１を形成した。なお用いたアクリル樹脂のガラス転移温度は、１００℃付近である。
続いて、加力発生器１３を用い、上金型１１と下金型１２とを嵌合させ、樹脂層２１を８ＭＰａの圧力でプレスした。
なお、上金型１１の鏡面１１１のＲａは、０．２０μｍ以下であった。
次に金型の冷却工程を行った。すなわち、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６に20℃の冷却水を流して急速に冷却した。上金型１１は冷却水を流さず、ゆっくり冷却した。この状態で上金型１１の鏡面１１１の温度が100℃になるまで前記プレス圧力を維持した。特に冷却初期20秒において、下金型１２の冷却速度は100℃／min であったのに対し、上金型１１の冷却速度は25℃／minと25℃／min以上の差があった。
続いて、上金型１１と下金型１２を開放し、得られた転写体を微細な凹凸部１２１から離型した。上金型１１と転写体との付着力と、急速冷却による微細な凹凸部１２１の離型促進によって転写体は微細な凹凸部１２１から簡単に離型することができた。この後、上金型１１に20℃の冷却水を通水し、60℃まで冷却すると同時に、非接触搬送体を金型内に進入させ、転写体を上金型１１から離型した。また、転写体は微細な凹凸部１２１の形状が忠実に転写されていることが確認できた。 Example 1
Example 1 was implemented using the apparatus shown in FIG.
After the heater 15 is activated and the lower mold 12 is heated to 140 ° C. and the upper mold 11 is heated to 140 ° C., the acrylic resin is heated to 235 ° C. to melt, and the vertical, horizontal, depth, and uneven portions The resin layer 21 was formed by applying a coating thickness of 130 μm on the fine irregularities 121 of the Ni stamper having an interval of 50 μm with a coating thickness of 130 μm. The glass transition temperature of the acrylic resin used is around 100 ° C.
Subsequently, using the force generator 13, the upper mold 11 and the lower mold 12 were fitted, and the resin layer 21 was pressed at a pressure of 8 MPa.
The Ra of the mirror surface 111 of the upper mold 11 was 0.20 μm or less.
Next, a mold cooling step was performed. That is, one minute after the pressurization was started, the heaters 15 of the upper mold 11 and the lower mold 12 were turned off, and the cooling pipe 16 of the lower mold 12 was poured into the cooling pipe 16 to rapidly cool it. . The upper mold 11 was cooled slowly without flowing cooling water. In this state, the press pressure was maintained until the temperature of the mirror surface 111 of the upper mold 11 reached 100 ° C. In particular, in the initial 20 seconds of cooling, the cooling rate of the lower mold 12 was 100 ° C./min, whereas the cooling rate of the upper mold 11 was different from 25 ° C./min by 25 ° C./min or more.
Subsequently, the upper mold 11 and the lower mold 12 were opened, and the obtained transfer body was released from the fine uneven portion 121. The transfer body could be easily released from the fine irregularities 121 by the adhesive force between the upper mold 11 and the transfer body and the promotion of mold release of the fine irregularities 121 by rapid cooling. Thereafter, cooling water at 20 ° C. was passed through the upper mold 11 and cooled to 60 ° C., and at the same time, the non-contact conveyance body was introduced into the mold and the transfer body was released from the upper mold 11. Further, it was confirmed that the shape of the fine uneven portion 121 was faithfully transferred on the transfer body.

実施例２
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６に20℃の冷却水を流して急速に冷却し、上金型１１は80℃の冷却水を流して冷却を行った。この時、冷却初期20秒間の下金型１２の冷却速度を100℃／min、上金型１１の冷却速度を50℃／minとなるように冷却媒体の流量を調整した。この場合についても実施例１と同様の結果を得た。 Example 2
In the mold cooling process of the first embodiment, the heating heater 15 of the upper mold 11 and the lower mold 12 is turned off one minute after the pressurization is started, and the cooling pipe 16 of the lower mold 12 is heated to 20 ° C. Cooling water was passed to cool rapidly, and the upper mold 11 was cooled by flowing 80 ° C. cooling water. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold 12 was 100 ° C./min and the cooling rate of the upper mold 11 was 50 ° C./min during the initial 20 seconds of cooling. In this case, the same result as in Example 1 was obtained.

実施例３
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６および上金型１１の冷却管１６に20℃の冷却水を流して冷却を行った。この時、冷却初期20秒間の下金型の冷却速度を100℃／min、上金型の冷却速度を 75℃／minとなるように冷却媒体の流量を調整した。この場合についても実施例１と同様の結果を得た。 Example 3
In the mold cooling process of the first embodiment, the heating heaters 15 of the upper mold 11 and the lower mold 12 are turned off one minute after the pressurization is started, and the cooling pipe 16 and the upper mold of the lower mold 12 are turned off. Cooling was performed by flowing 20 ° C. cooling water through 11 cooling pipes 16. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold was 100 ° C./min and the cooling rate of the upper mold was 75 ° C./min during the initial 20 seconds of cooling. In this case, the same result as in Example 1 was obtained.

実施例４
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６に80℃の冷却水を流して冷却し、上金型１１は冷却水を流さず、ゆっくり冷却した。この時、冷却初期20秒間の下金型の冷却速度を50℃／min、上金型の冷却速度を25℃／minとなるように冷却媒体の流量を調整した。この場合についても実施例１と同様の結果を得た。 Example 4
In the mold cooling process of Example 1, one minute after starting pressurization, the heaters 15 of the upper mold 11 and the lower mold 12 are turned off, and the cooling pipe 16 of the lower mold 12 is heated to 80 ° C. The cooling was performed by flowing cooling water, and the upper mold 11 was slowly cooled without flowing cooling water. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold was 50 ° C./min and the cooling rate of the upper mold was 25 ° C./min during the initial 20 seconds of cooling. In this case, the same result as in Example 1 was obtained.

比較例１
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６および上金型１１の冷却管１６に20℃の冷却水を流して急速に冷却した。この時、冷却初期20秒間の下金型１２の冷却速度を100℃／min、上金型１１の冷却速度を100℃／minとなるように冷却媒体の流量を調整した。この場合、上金型１１および下金型２１を開放する際に、転写体が下金型１２の微細な凹凸部１２１に付着し、これを剥離する際に、下記で説明する図１０（ａ）のような形状の崩れなどの不良が発生した。 Comparative Example 1
In the mold cooling process of the first embodiment, the heating heaters 15 of the upper mold 11 and the lower mold 12 are turned off one minute after the pressurization is started, and the cooling pipe 16 and the upper mold of the lower mold 12 are turned off. Eleven cooling pipes 16 were rapidly cooled by flowing cooling water at 20 ° C. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold 12 was 100 ° C./min and the cooling rate of the upper mold 11 was 100 ° C./min during the initial 20 seconds of cooling. In this case, when the upper mold 11 and the lower mold 21 are opened, the transfer body adheres to the fine irregularities 121 of the lower mold 12, and when this is peeled off, FIG. Defects such as shape collapse occurred.

比較例２
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６および上金型１１の冷却管１６に80℃の冷却水を流して冷却した。この時、冷却初期20秒間の下金型の冷却速度を50℃／min、上金型の冷却速度を50℃／minとなるように冷却媒体の流量を調整した。この場合も前記比較例1と同様に形状の崩れなどの不良が発生した。 Comparative Example 2
In the mold cooling process of the first embodiment, the heating heaters 15 of the upper mold 11 and the lower mold 12 are turned off one minute after the pressurization is started, and the cooling pipe 16 and the upper mold of the lower mold 12 are turned off. 11 cooling pipes 16 were cooled by flowing 80 ° C. cooling water. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold was 50 ° C./min and the cooling rate of the upper mold was 50 ° C./min during the initial 20 seconds of cooling. In this case as well, defects such as shape collapse occurred as in Comparative Example 1.

比較例３
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６および上金型１１の冷却管１６に空気を流して冷却した。この時、冷却初期20秒間の下金型１２の冷却速度を25℃／min、上金型１１の冷却速度を25℃／minとなるように冷却媒体の流量を調整した。この場合も前記比較例1と同様に形状の崩れなどの不良が発生した。 Comparative Example 3
In the mold cooling process of the first embodiment, the heating heaters 15 of the upper mold 11 and the lower mold 12 are turned off one minute after the pressurization is started, and the cooling pipe 16 and the upper mold of the lower mold 12 are turned off. 11 cooling pipes 16 were cooled by flowing air. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold 12 was 25 ° C./min and the cooling rate of the upper mold 11 was 25 ° C./min during the initial 20 seconds of cooling. In this case as well, defects such as shape collapse occurred as in Comparative Example 1.

比較例４
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６に80℃の冷却水を流し、上金型１１の冷却管１６に20℃の冷却水を流して冷却を行った。この時、冷却初期20秒間の下金型１２の冷却速度を50℃／min、上金型１１の冷却速度を100℃／minとなるように冷却媒体の流量を調整した。この場合も前記比較例1と同様に形状の崩れなどの不良が発生した。 Comparative Example 4
In the mold cooling process of Example 1, one minute after starting pressurization, the heaters 15 of the upper mold 11 and the lower mold 12 are turned off, and the cooling pipe 16 of the lower mold 12 is heated to 80 ° C. Cooling water was poured, and cooling was performed by flowing 20 ° C. cooling water through the cooling pipe 16 of the upper mold 11. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold 12 was 50 ° C./min and the cooling rate of the upper mold 11 was 100 ° C./min for the initial 20 seconds of cooling. In this case as well, defects such as shape collapse occurred as in Comparative Example 1.

比較例５
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６に空気を流し、上金型１１の冷却管に80℃の冷却水を流して冷却した。この時、冷却初期20秒間の下金型１２の冷却速度を25℃／min、上金型１１の冷却速度を50℃／minとなるように冷却媒体の流量を調整した。この場合も前記比較例1と同様に形状の崩れなどの不良が発生した。 Comparative Example 5
In the mold cooling process of the first embodiment, the heater 15 of the upper mold 11 and the lower mold 12 is turned off one minute after the pressurization is started, and air is allowed to flow through the cooling pipe 16 of the lower mold 12. The cooling pipe of the upper mold 11 was cooled by flowing 80 ° C. cooling water. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold 12 was 25 ° C./min and the cooling rate of the upper mold 11 was 50 ° C./min for the initial 20 seconds of cooling. In this case as well, defects such as shape collapse occurred as in Comparative Example 1.

比較例６
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６に空気を流し、上金型１１の冷却管１６に20℃の冷却水を流して冷却を行った。この時、冷却初期20秒間の下金型１２の冷却速度を25℃／min、上金型１１の冷却速度を100℃／minとなるように冷却媒体の流量を調整した。この場合も前記比較例1と同様に形状の崩れなどの不良が発生した。 Comparative Example 6
In the mold cooling process of the first embodiment, the heater 15 of the upper mold 11 and the lower mold 12 is turned off one minute after the pressurization is started, and air is allowed to flow through the cooling pipe 16 of the lower mold 12. The cooling was performed by flowing cooling water at 20 ° C. through the cooling pipe 16 of the upper mold 11. At this time, the flow rate of the cooling medium was adjusted so that the cooling rate of the lower mold 12 was 25 ° C./min and the cooling rate of the upper mold 11 was 100 ° C./min during the initial 20 seconds of cooling. In this case as well, defects such as shape collapse occurred as in Comparative Example 1.

実施例５
実施例１の金型の冷却工程において、加圧を開始して１分間後に上金型１１と下金型１２の加熱ヒータ１５をオフにして、下金型１２の冷却管１６にのみ20℃の冷却水を流して急速に冷却した。この時、下金型１２の微細な凹凸部の温度が１００℃になるまでプレス圧力を維持した。その後、下金型１２の微細な凹凸部１２１と上金型１１の鏡面１１１との距離を加圧時の樹脂層２１の厚さと同じに維持した状態で金型の位置を保持し、上金型１１の鏡面１１１の温度が100℃になるまで、下金型の冷却管に冷却水を流した場合についても、実施例１と同様の結果を得た。 Example 5
In the mold cooling process of the first embodiment, the heating heaters 15 of the upper mold 11 and the lower mold 12 are turned off one minute after the pressurization is started, and only 20 ° C. is applied to the cooling pipe 16 of the lower mold 12. The cooling water was poured to cool rapidly. At this time, the press pressure was maintained until the temperature of the fine irregularities of the lower mold 12 reached 100 ° C. Thereafter, the position of the mold is maintained in a state where the distance between the fine uneven portion 121 of the lower mold 12 and the mirror surface 111 of the upper mold 11 is kept the same as the thickness of the resin layer 21 at the time of pressurization. The same results as in Example 1 were obtained when cooling water was passed through the cooling pipe of the lower mold until the temperature of the mirror surface 111 of the mold 11 reached 100 ° C.

実施例６
前記各実施例において、樹脂層21を形成する際に、Ni製の微細な凹凸部121上に市販のアクリル樹脂シート（厚さ 0.5 mm）を設置した場合についても、前記と同様の結果を得た。
さらに、前記各実施例２〜４の金型の冷却工程において、上金型１１および下金型１２の加熱ヒータ１５をオフにして、上金型１１および下金型１２もしくは下金型１２の冷却管１６に冷却水を流した状態で、下金型１２の微細な凹凸部１２１が１００℃になるまで前記プレス圧力を維持した後、下金型１２の微細な凹凸部１２１と上金型１１の鏡面１１１との距離を加圧時の樹脂層２１の厚さと同じに維持した状態で金型の位置を保持し、上金型１１の鏡面１１１の温度が100℃になるまで、上金型１１および下金型１２あるいは下金型１２の冷却管１６に冷却水を流した場合についても、実施例1と同様の結果を得た。 Example 6
In each of the above examples, when the resin layer 21 was formed, the same result as described above was obtained when a commercially available acrylic resin sheet (thickness 0.5 mm) was placed on the fine uneven portion 121 made of Ni. It was.
Further, in the mold cooling process of each of the embodiments 2 to 4, the heaters 15 of the upper mold 11 and the lower mold 12 are turned off, and the upper mold 11 and the lower mold 12 or the lower mold 12 After maintaining the pressing pressure until the fine irregularities 121 of the lower mold 12 reach 100 ° C. in the state where the cooling water is supplied to the cooling pipe 16, the fine irregularities 121 of the lower mold 12 and the upper mold 11 while maintaining the position of the mold in a state where the distance from the mirror surface 111 is the same as the thickness of the resin layer 21 at the time of pressurization, and until the temperature of the mirror surface 111 of the upper mold 11 reaches 100 ° C. The same results as in Example 1 were obtained when cooling water was passed through the mold 11 and the lower mold 12 or the cooling pipe 16 of the lower mold 12.

上記実施例１〜４および比較例１〜６における金型冷却速度と微細凹凸形状の不良との関係を下記表１に示す。 Table 1 below shows the relationship between the mold cooling rate and the fine unevenness in Examples 1 to 4 and Comparative Examples 1 to 6.

なお、前記特許文献１（特開２００２−５９４４０号公報）などに記載の方法、すなわち機械式イジェクタ部によって転写体５１を離型する方法では、転写体に転写された微細な凹凸部のエッジ部がめくれたり、角柱部の上面の傾き、角柱の倒れなどが生じ、微細な凹凸部１２１の形状を忠実に転写することができなかった。 In the method described in Patent Document 1 (Japanese Patent Laid-Open No. 2002-59440), that is, the method in which the transfer body 51 is released by a mechanical ejector portion, the edge portion of the fine uneven portion transferred to the transfer body. The shape of the fine uneven portion 121 could not be faithfully transferred due to turning over, tilting of the upper surface of the prism, or falling of the prism.

前記実験結果の、転写体５１の微細な凹凸部のレーザー顕微鏡写真を図９に示す。図９の（ａ）は、前記特許文献１（特開２００２−５９４４０号公報）などに記載の従来法であり、転写体に転写された微細な凹凸部のエッジ部がめくれたり、角柱部の上面の傾き、角柱の倒れがなどが生じていることが分かる。これに対し、図９（ｂ）に示される本発明の方法により調製された転写体５１は、微細な凹凸部１２１の形状が忠実に転写されていることが分かる。 FIG. 9 shows a laser micrograph of the fine irregularities of the transfer body 51 as a result of the experiment. FIG. 9A shows a conventional method described in Patent Document 1 (Japanese Patent Laid-Open No. 2002-59440) and the like. It can be seen that the top surface is tilted and the prism is tilted. In contrast, the transfer body 51 prepared by the method of the present invention shown in FIG. 9B shows that the shape of the fine uneven portion 121 is faithfully transferred.

本発明によれば、装置構成が複雑な特殊な金型を必要とせず、表面に微細な凹凸部を有する成形体を、その凹凸形状を良好に維持しながら、金型から迅速に、容易に、かつ確実に離型することのできる成形体の製造方法を提供することができ、数十ｎｍから数百μｍの超微細な凹凸形状を表面に有するとともに、三次元、薄肉、かつ大面積の形状を有する、マイクロレンズ・アレイのような電子ディスプレイ用光学部品、マルチモード光導波路のような光情報通信用部品、マイクロ化学チップのようなライフサイエンス部品等の製造に有用である。 According to the present invention, a special mold having a complicated apparatus configuration is not required, and a molded body having fine uneven portions on the surface can be quickly and easily maintained from the mold while maintaining its uneven shape. And a method for producing a molded body that can be surely released, and has an ultra-fine uneven shape of several tens of nm to several hundreds of μm on the surface, and has a three-dimensional, thin wall, and large area. It is useful for manufacturing optical parts for electronic displays such as microlens arrays, optical information communication parts such as multimode optical waveguides, and life science parts such as microchemical chips having a shape.

本発明に使用できる金型装置の一実施形態の概略断面図である。It is a schematic sectional drawing of one Embodiment of the metal mold | die apparatus which can be used for this invention. 本発明の製造方法の（２）工程を説明するための図である。It is a figure for demonstrating the (2) process of the manufacturing method of this invention. 本発明の製造方法の（３）工程を説明するための図である。It is a figure for demonstrating the (3) process of the manufacturing method of this invention. 鏡面の温度に対する、ポリスチレン(PS)の付着力（引き剥がし力）の関係を説明するための図である。It is a figure for demonstrating the relationship of the adhesive force (peeling force) of polystyrene (PS) with respect to the temperature of a mirror surface. 微細な凹凸部に充填された樹脂層の体積収縮およびズリ変形を説明するための、微細な凹凸部と樹脂層の拡大断面図である。It is an expanded sectional view of a fine uneven | corrugated | grooved part and a resin layer for demonstrating volume shrinkage | contraction and shear deformation | transformation of the resin layer with which the fine uneven | corrugated | grooved part was filled. 本発明の製造方法における（５）工程を説明するための図である。It is a figure for demonstrating the (5) process in the manufacturing method of this invention. 上金型の鏡面から下金型の微細な凹凸部への熱の流れを説明するための図である。It is a figure for demonstrating the flow of the heat | fever from the mirror surface of an upper metal mold | die to the fine uneven | corrugated | grooved part of a lower metal mold | die. 金型の位置保持による効果を説明するための図である。It is a figure for demonstrating the effect by position holding of a metal mold | die. （ａ）は、従来法により調製された転写体の微細な凹凸形状のレーザー顕微鏡写真、（ｂ）は、本発明の方法により調製された転写体の微細な凹凸形状のレーザー電子顕微鏡写真である。(A) is a laser micrograph of a fine concavo-convex shape of a transfer member prepared by a conventional method, and (b) is a laser electron micrograph of a fine concavo-convex shape of a transfer member prepared by the method of the present invention. .

Explanation of symbols

１金型装置
１１上金型
１１１鏡面
１２下金型
１２１微細な凹凸部
１３加力発生器
１５加熱ヒータ
１６冷却管
２１樹脂層
５１転写体 DESCRIPTION OF SYMBOLS 1 Mold apparatus 11 Upper mold 111 Mirror surface 12 Lower mold 121 Fine uneven part 13 Force generator 15 Heater 16 Cooling tube 21 Resin layer 51 Transfer body

Claims

The manufacturing method of the molded object characterized by having the following (1)-(5) process sequentially.
(1) An upper mold and a lower mold having a mirror surface on one mold surface and a fine uneven portion on the other mold surface are prepared, and the mirror surface and the fine uneven portion are formed in the following step (2) The step of raising the glass transition temperature of the thermoplastic resin used in the step to ± 10 ° C. or higher than the glass transition temperature;
(2) The process of providing the resin layer of a thermoplastic resin on the said fine uneven part;
(3) closing the upper mold and the lower mold, applying pressure between both molds, and transferring the shape of the fine irregularities to the resin layer to form a transfer body;
(4) The mirror surface is cooled at a cooling rate of 50 ° C./min or more below the glass transition temperature of the thermoplastic resin while the transfer body is attached to the fine asperities. A step of cooling at a speed that is at least 25 ° C./min faster than the speed to reduce the adhesion between the fine irregularities and the transfer body; and (5) the upper metal while the transfer body is adhered to the mirror surface A step of opening the mold and the lower mold in a direction perpendicular to the surface of the fine uneven portion, and releasing the transfer body from the fine uneven portion.

In the step (4), after stopping the heating of both molds, in a state where the mold having the mirror surface is allowed to cool, cooling water of 30 ° C. or less is passed through the mold having the fine irregularities. method for producing a molded article according to claim 1, characterized in that the cooling Te.

The method according to claim 1 or 2 , wherein the fine uneven portion is a stamper having a fine uneven portion on a surface.