JP4109234B2 - Fine transfer method and apparatus - Google Patents

Description

  The present invention relates to a fine transfer method and apparatus, and more particularly, a fine transferable product capable of producing a product excellent in comparison with the conventional hot embossing method, injection molding method, compression molding method, and nanoimprint method with high productivity. The present invention relates to a transfer method and apparatus. According to the method and apparatus of the present invention, it is possible to obtain a large-area product having a fine uneven shape on the surface and a side length of several centimeters to several tens of centimeters.

  A member made of a material such as thermoplastic, thermosetting plastic, photo-curable plastic or low-melting glass and having a surface with a fine irregular shape of several nanometers to several hundreds of micrometers includes a diffraction grating, a microlens array, Optical parts such as CD, DVD, Blu-ray disc pickup lens, optical storage media such as CD, DVD, Blu-ray Disk, large-capacity hard disk, optical waveguide, optical switch, optical fiber bonding V-groove, connector, etc. Electronic display parts such as communication parts, light guide plate for liquid crystal display, high brightness front light, wave plate, surface non-reflective structure, organic EL receptor, organic TFT partition, optical phase plate, μ-TAS, chemical synthesis chip, DNA chip , Fingerprint sensor array, protein chip, microbe detection chip, diagnostic chip, etc. There is such as scan member. Current methods for producing these members include injection molding, hot embossing, and nanoimprinting.

  In the injection molding method, fine irregularities from several hundred nm are formed on the mold surface, and heated and melted resin is filled into a closed mold at a high pressure of several tens of MPa to 200 MPa, cooled and solidified to release. It is a method of taking out. This method has extremely high productivity, can freely form a complicated three-dimensional shape, and is easy to automate, and is the most popular plastic molding method. DVDs having fine pits with a width of several hundreds of nanometers are produced with a cycle time of about 3 seconds by the injection molding method. Moreover, it is applied to many members having a fine unevenness of several hundred nm to several hundred μm on the surface, such as a lens, a diffraction grating, and a light guide plate for a liquid crystal display backlight. However, since a molten resin at 200 to 350 ° C. is filled at a high pressure in a mold cooled to near normal temperature, high residual stress, birefringence, distortion, and warp deformation are generated in the molded product, and the optical characteristics are easily impaired. In addition, the pressure gradient from the mold sprue that starts filling the resin to the flow end is large, the resin is not sufficiently filled at the flow end, and further, as the resin advances toward the flow end, the resin moves into the mold. Since the temperature is lowered and the fluidity is lowered due to cooling, there is a problem that it is difficult to transfer the fine uneven shape of the mold wall surface at the flow end. In addition, since the resin flows while contacting the cooled mold surface, the viscosity of the resin in contact with the mold wall surface increases, and further, a solidified layer of resin is formed near the mold wall surface. The formed fine uneven shape could not be filled, and it was difficult to obtain sufficient transferability.

  In the hot embossing method, a solid resin is loaded into a mold, the mold is heated to near the glass transition temperature of the resin, and the resin is heated and softened by pressurizing the resin with the mold. This is a molding method in which a resin is pressurized and filled in a part, and then the resin is cooled and solidified to be released. The fine irregularities of the mold are applied by machining the mold directly or by attaching a plate-shaped stamper with fine irregularities formed on the surface by the LIGA process or ft lithography technology. Is done. By this method, it is said that fine irregularities of nanometer to micrometer can be formed on the resin. This method is said to be advantageous for molding minute uneven shapes because the flow deformation amount and deformation speed of the resin are smaller than those of injection molding. In addition, there is a merit that the amount of deformation of the resin due to flow is small and the heating proceeds slowly while maintaining a steady state, so that the residual stress inside the molded product is small. Furthermore, since the pressure gradient necessary for generating the flow is small and the pressure is uniformly applied in the plane of the resin, molding can be performed at a low pressure, and a thin molded product can be easily obtained. However, since it takes several minutes to heat and cool the mold within one molding cycle, the productivity is low, and the molding cycle takes several seconds to several tens of seconds to fill the cooled mold with resin. On the other hand, the hot embossing method that requires heating and cooling of the mold within one cycle requires several minutes to several tens of minutes. Moreover, even if heat softening is performed, a resin close to a solid is subjected to pressure deformation, and thus a high pressure of several tens of MPa is required. Furthermore, by deforming the resin close to the solid state, when the fine convex portion of the mold is pushed into the resin, a large elastic deformation and roundness are generated at the corner of the resin, and the distortion of this portion increases and the optical characteristics are impaired. There is. The quality of the molded product is not limited to the shape accuracy. In optical parts, display elements, etc., it is particularly necessary to improve the properties (residual strain, birefringence distribution) inside the molded product. It can be said that impairing the optical characteristics is a fundamental drawback. Furthermore, when the fine convex portion is pushed into the mold, air is confined in the fine concave portion of the mold, which inhibits the transfer of the fine concave and convex portion of the mold to the resin. For this reason, it is necessary to perform molding while maintaining the inside of the mold in a vacuum state, and there is a problem that equipment cost increases, and time is required for evacuation and release to the atmospheric pressure, thereby impairing productivity. Moreover, the product shape to be obtained is limited to a planar shape, and there is a restriction that it is difficult to make an uneven shape rather than a three-dimensional shape. Furthermore, since it is necessary to supply a solid plastic in the form of a film or sheet, the plastic must be prepared in the form of a film or sheet prior to molding.

  The nanoimprint method is a method proposed by Prince of Princeton University in 1995. A mold (mold) with fine irregularities on the nanometer scale is pressed against a resin resist formed on a wafer substrate, and the structure of the mold is resisted. To form a fine concavo-convex shape in the resist. As a result, it is described that a fine concavo-convex pattern having a width of 200 nm or less and about 25 nm is formed (Patent Document 1 below). However, this method is different from the hot embossing method described above except for the point that the mold is pressed against the resin thin film formed on the substrate and the fine pattern of 200 nm or less can be formed. And therefore has the same problems as the hot embossing method.

On the other hand, in Patent Document 2 below, a part of a mold in plastic injection molding is made of a material that transmits infrared rays, and the resin in the molding process is irradiated with, for example, a carbon dioxide laser to increase the cooling rate of the molten resin. A method of controlling has been proposed. It has been shown that by irradiating the resin in the mold during injection filling with a carbon dioxide laser in the range of φ4 mm, birefringence due to molecular orientation can be removed, transferability can be improved, and the like. Moreover, since the temperature of the infrared transmitting material hardly rises, there is no need to set the mold temperature high as in the prior art to improve transferability, and therefore there is no need to extend the cooling time, so high productivity can be obtained. It has been shown that By direct infrared radiation heating of the resin in contact with the mold wall by carbon dioxide laser irradiation, the generation of the surface solidified layer during filling is suppressed, and the residual birefringence due to flow and solidification is reduced. It has been shown that the transferability of the resin is improved with respect to fine irregularities having a width of 100 μm, 200 μm, and a depth of 100 μm. Examples of the infrared light source include a carbon dioxide laser, a YAG laser, and an infrared lamp, and the infrared light source can be appropriately selected within a range that the polymer absorbs. Moreover, ZnSe, sapphire, and infrared glass are shown as the infrared transmitting material. In the example, by irradiating the filling resin with a carbon dioxide gas laser having an irradiation density of 80 W / cm ² , the resin on the mold wall surface becomes high temperature, the solidified layer disappears, the molecular alignment layer is not formed, and the optical It is shown that there is no deviation in characteristics, residual birefringence disappears, and transferability is improved. However, all of these results were obtained by irradiating infrared rays onto a very small area of Φ4 mm of the molded product. The effect of improving transferability by irradiating a large area and the surface condition when irradiated In particular, there has been no confirmation of the occurrence of side effects such as irradiation unevenness, poor appearance in the irradiated portion and non-irradiated portion, burning due to high irradiation density, and discoloration.
In addition, ZnSe, which is an infrared transmitting material, becomes extremely expensive as the thickness increases. Furthermore, ZnSe is a brittle material that is difficult to process, and under high pressures where the resin pressure in the mold reaches several tens of MPa to 200 MPa like injection molding, it is necessary to keep the bending stress due to the resin pressure very low compared to steel, For this reason, it is difficult to use a ZnSe having a large area and a thick wall because bending stress increases. Further, even if there is an infrared transmitting material having a large area and sufficient strength, a large-output infrared light source is required to irradiate infrared rays necessary for the large area, which is not economically appropriate. It was difficult to process into a fine concavo-convex shape, and it was the limit that could process a concavo-convex shape of 100 to 200 μm. For these reasons, the technique of Patent Document 2 has not been put into practical use for a molded article having a medium to large area necessary for practical use.

On the other hand, in Patent Document 3, a base material made of a plastic material having a transfer surface is prepared, the base material is fixed with the transfer surface exposed, and at least a part of the stamper made of an infrared transmitting material is molded. There is disclosed a plastic molding method characterized in that the surface is held in close contact with the transfer surface of the substrate, and infrared rays are irradiated in the direction of the substrate toward the stamper. As a result, while maintaining high productivity like injection molding, the transferability of the plastic material is improved, and a molded product having uniform physical characteristics (for example, optical characteristics) is provided. Yes. In the embodiment, a thin disk such as a CD-ROM is shown as a substrate having a transfer surface. This is a method in which the transfer surface of the substrate is molded by irradiating infrared rays through an infrared transmitting material, and the transfer property is improved by irradiating infrared rays with respect to the hot embossing method.
However, in this method, when a part of the shaping surface is irradiated with infrared rays, only the irradiated part is transferred, the other part is not transferred, and the irradiation unevenness between the irradiated part and the non-irradiated part. As a result, the smoothness of the molding surface is impaired. This method does not show a method for uniformly irradiating the entire transfer surface with infrared rays. In addition, according to the experiments by the present inventors, it is known that even if infrared rays are irradiated, the fine uneven shape on the stamper surface cannot be transferred to a sufficient depth unless there is a pressure of at least about 0.1 to 1 MPa. . Therefore, as shown in Patent Document 3, it is difficult to improve the transferability of the molding surface without applying pressure.

Non-patent document 1 below proposes a two-step infrared-assisted precision transfer method. In this method, first, a molded article that satisfies almost the required dimensions is formed by a conventional injection molding method or the like. Next, the molded product is inserted into a mold having a precise dimension and partially provided with an infrared transmitting material, and infrared rays are irradiated from the outside to raise the resin surface temperature and melt the thin layer. At that time, volume expansion occurs due to temperature rise and the pressure inside the mold also rises, so that precise transfer is possible. It has been experimentally verified that CD disks can also be transfer molded. As a result of the experiment, a triangular groove having a width of 2 μm and a depth of 5.6 μm was transferred almost 100% at a pressure of 1 MPa, a mold temperature of 100 ° C., and an irradiation density of 55 W / cm ² . However, when a molded product is loaded in a closed mold and infrared rays are irradiated to a stamper having a fine uneven shape, the air remaining in the fine unevenness inhibits the transfer. As a result, in this molding method, it takes 60 seconds for the transfer even though the pressure is increased to 1 MPa and the mold temperature is raised to 100 ° C. Also in this molding method, the configuration for attaching the infrared transmitting material in the mold is almost the same as that of the injection mold described in Patent Document 2, and even though it requires a lower pressure than the injection molding, it is made of a brittle material. In order to increase the area of a certain infrared transmitting material, it is necessary to increase the thickness of the infrared transmitting material. As a result, it is necessary to increase the molding time due to high cost and increased stamper cooling time. Further, the transferable area is only φ12 mm, and no transfer is shown for a large area. Furthermore, no consideration is given to mold release after transfer to a fine shape.

  Note that Patent Document 4 discloses another transfer method using infrared radiation. This is a method of transferring a fine pattern formed on a mold to the substrate surface. A mold having a fine pattern on the surface is prepared, the mold surface is adjacent to the substrate surface to be transferred, and the substrate surface is softened. Alternatively, the substrate surface is sprayed to liquefy, the mold surface is pressurized toward the softened or liquefied substrate surface, the mold is moved, and the substrate onto which the fine shape pattern on the mold surface has been transferred is peeled off. It is. Here, laser radiation is used as radiation, the wavelength of laser radiation is 1 nm to 100 μm, radiation may be lamp radiation, and infrared radiation is also included. In addition, the mold may be an infrared transmitting material, the substrate may be a polymer, and the mold or the entire substrate may be heated by radiation without substantially heating. Since these are substantially the same as the techniques of Patent Documents 2 and 3 and Non-Patent Document 1, they have the same problems as described above. In other words, the entire transfer surface is uniformly irradiated so that there is no irradiation unevenness, and a smooth surface is obtained. By simply pressing the mold against the substrate, the air remaining in the fine uneven shape of the mold is transferred to the portion. In the case of using a thin stamper having a large area, the infrared transmitting material which is a brittle material is damaged due to the action of bending by pressurizing, and the method for facilitating mold release is lacking. Furthermore, as in the technique disclosed in Patent Document 4, when a mold is pressed against a thin polymer layer formed on the substrate surface to form a fine uneven shape, it is difficult to separate the polymer layer from the mold. However, the specific mold release method is not specified. Moreover, it is possible to form a fine uneven surface only on one side of the substrate surface to the polymer by this method, and it is impossible to form fine unevenness on both surfaces.

1998 New Energy / Industrial Technology Development Organization / New Industry Creation Type Proposal Public Research Project Research Results Report, “Ultra-precision syntax injection molding with support for infrared irradiation: Development of technology to improve transfer and formability”, March 2000 ) US Pat. No. 5,772,905 Japanese Patent No. 3169786 JP 2001-158044 A US Patent Application Publication No. 2004 / 046288A1

The problems of the conventional techniques as described above can be summarized as follows.
(1) High transferability and optical characteristics of fine irregularities In the injection molding method, the molten resin is filled into a low-temperature mold, so that the resin in contact with the mold wall is cooled rapidly and the temperature drops, resulting in high viscosity. The solidification and solidification layer is formed and the resin is difficult to be filled into the fine irregularities of the mold wall surface, so that the transferability is impaired. In addition, since the resin is cooled on the mold wall surface and flows while increasing in viscosity and solidification, high residual stress, birefringence, distortion, and warp deformation occur near the mold wall surface, and the optical characteristics are impaired.
The hot embossing method and the nano-imprint method are advantageous for forming fine irregularities and the residual stress is small because the flow deformation amount and deformation speed of the resin during molding are small compared to injection molding. It is said. However, since the resin close to a solid state is deformed under pressure, there is a problem that when the fine convex portion is pushed into the substrate, a large elastic deformation is generated at the corner portion of the resin and the optical characteristics are impaired.
As disclosed in Patent Documents 2 and 3, in a method in which a mold wall surface or a stamper is formed of an infrared transmitting material and the resin in contact with the mold wall is directly heated and melted by irradiating infrared rays from the outside, High transferability of fine unevenness formed on the surface of the stamper is obtained, and residual stress and birefringence are reduced. However, a material with good workability is required to process a fine uneven shape into an infrared transmitting material. It is difficult to process ZnSe or ZnS with light transmittance of 90% or more. In order to obtain high transferability with high productivity, it is necessary to apply a pressure of about 0.1 to 1 MPa in addition to infrared irradiation. However, in general, the infrared transmitting material is a brittle material, and when the applied pressure is increased, there is a high possibility that the material is damaged by bending. Further, the infrared transmittance depends on the thickness of the infrared transmitting material, and the transmittance decreases as the thickness increases. Silicon that can be finely processed by etching or the like has a transmittance of about 43% for a carbon dioxide gas laser with a wavelength of 10.6 μm at a thickness of 1 mm or less, but is 9% or less at a thickness of 5 mm and 1.8% at a thickness of 10 mm. It becomes. For this reason, in order to obtain high fine transferability, it is necessary to use an infrared transmitting material that is as thin as possible. Further, when the fine uneven shape formed on the mold or the stamper is pushed into the plastic substrate, the air enclosed in the fine recess becomes a resistance, and the transfer to the fine unevenness is inhibited. For this reason, even in the case of using infrared radiation heating, in order to obtain high transferability, use an infrared transmitting material that is thin and has good workability as much as possible while applying pressure, and is also transferred by air containment. There is a need to take new steps to resolve sexual inhibition.

(2) Heating / cooling time and molding pressure In the hot embossing method or nanoimprinting method, the mold, stamper or plastic substrate is heated to the vicinity of the glass transition temperature of the plastic by heating means such as an electric heater or heating medium. Is pressed against a plastic substrate to form a fine irregular shape on the plastic surface, and then the plastic substrate is cooled to near room temperature and released. In this case, heating and cooling require at least a few minutes to a sufficient time, thereby impairing productivity and increasing the cost of the product. In addition, in order to pressurize solid plastic and soften it by heat transfer from the stamper, a high pressure exceeding 10 MPa is required, and the stamper and the mold require rigidity. In addition, when pressing the bumps of the stamper on the plastic, the softened plastic shows viscoelastic deformation, and the part that does not contact the stamper is deformed as a solid, so that distortion occurs in this part, resulting in birefringence and optical characteristics. Will be damaged. Therefore, it is necessary to shorten the time required for heating and cooling the stamper and the plastic substrate as much as possible and to take measures to reduce the pressure required for molding.
As disclosed in Patent Documents 2 and 3, in a method in which a mold wall surface or a stamper is formed of an infrared transmitting material and the resin in contact with the mold wall is directly heated and melted by irradiating infrared rays from the outside, Since the resin can be heated instantaneously directly without heating the stamper, the production time is shortened. In the technique disclosed in Non-Patent Document 1, a fine unevenness of 100 μm is formed under conditions of molding 1 MPa, mold temperature 100 ° C., pressurization and infrared irradiation time 60 seconds, irradiation density 55 W / cm ^2. % Is transferred. However, it is necessary to raise the mold to 100 ° C, which takes 60s. Therefore, in order to achieve high transferability and molding at a low pressure of 1 MPa or less while ensuring high productivity comparable to injection molding, the heating and cooling time required to ensure high transferability is reduced, and low pressure It is necessary to take new measures that can be used.

(3) Prevention of damage and cost reduction of infrared transmitting material In the method disclosed in Patent Document 2, the infrared transmitting material is inferior in toughness and strength as compared with a normal mold material. For this reason, in the injection molding method in which a resin pressure of at least 10 MPa or more is applied to the infrared transmitting material, the infrared transmitting material is damaged, so that it is difficult to withstand practical use. Infrared transmitting materials such as silicon and germanium rapidly decrease in infrared transmittance as the thickness increases, so the usable thickness is limited to 1 mm for silicon and 10 mm for germanium, which is required for injection molding. It was difficult to withstand high pressure. In addition, infrared transmitting materials such as ZnSe, ZnS, Si, and Ge are not practical from this point because the price increases rapidly as the area increases and the thickness increases. On the other hand, in the technique disclosed in Patent Document 3, a plastic substrate is fixed to the surface of a stamper made of an infrared transmitting material having a fine uneven shape, and infrared rays are irradiated from the back of the stamper to add the plastic substrate. It is said that a fine uneven shape can be transferred to a plastic substrate without pressing. However, according to the experiments by the present inventors, even when infrared radiation heating is used, pressurization of 1 MPa or less is necessary to achieve sufficiently fine uneven shape transfer. Further, when a sufficient pressing force is applied to the transfer, there is a problem that the infrared transmitting material is broken as the area of the transfer surface is increased. For this reason, even if the transfer pressure is lowered as much as possible, the minimum pressing force necessary to form a fine uneven shape on a plastic substrate having a medium to large area (several centimeters to several tens of centimeters) is applied. It is necessary to take measures to prevent the infrared transmitting material from being damaged. Further, for the purpose of reducing the cost and increasing the infrared transmittance, it is necessary to use a thin infrared transmitting material as much as possible and to take a new means capable of applying pressure.

(4) Larger area In any case, the conventional method of forming a fine uneven shape on the surface of the plastic substrate by irradiating the plastic substrate with infrared rays through a mold or stamper made of an infrared transmitting material, A small diameter beam with a diameter of about 4 to 12 mm is irradiated onto a small part of the plastic, and the transferability and optical characteristics of the irradiated part are only evaluated, and the side length is medium to large area of several centimeters to several tens of centimeters. There is no report on a method and an apparatus for irradiating infrared rays to the entire molded body. That is, the effect of improving transferability by irradiation to a large area and the surface condition when irradiated are not reported. In particular, when only a part of the molded body is irradiated with infrared rays, transfer unevenness occurs at the boundary between the irradiated part and the non-irradiated part, and the surface becomes uneven and the appearance is impaired. In addition, when the irradiation density is high, if the specific part is continuously irradiated, the plastic base material is burned and discolored. For this reason, in order to obtain high transferability and smooth surface properties by uniformly irradiating infrared rays onto a large-area molded product through an infrared-transmitting material, a large-area infrared transmitting material is prepared, and infrared rays are uniformly applied to this material. It is necessary to take new measures for irradiation. However, particularly when an infrared laser is used, an extremely high-power laser is necessary to simultaneously irradiate a large area with a single beam. Therefore, it is conceivable to irradiate a single beam in a linear form. In this case, while irradiating a plastic base material with a linear infrared beam through an infrared transmitting material, the infrared light is uniformly applied to the entire surface of the base material. As described above, a novel method for obtaining a smooth transfer surface free from uneven irradiation while applying pressure to ensure the transferability of the fine uneven shape as described above is taken. There is a need. However, if pressure is applied to a large-area infrared transmitting material, even if the pressure acting on the plastic is low, a large force is applied to the entire area, and the bending stress acting on the infrared transmitting material increases, so there is a possibility of destruction. Becomes higher. Therefore, if the infrared transmitting material is thickened, the infrared transmittance decreases depending on the material, and the transferability to a fine uneven shape is impaired. Further, the thicker, the more time is required for heating and cooling, and the economical efficiency and productivity are impaired. Therefore, even if a large-area infrared transmitting material is pressed while being uniformly irradiated with infrared rays, a mechanism that does not cause bending stress that would cause destruction to the infrared transmitting material is used. It is necessary to realize a high transferability with use of fine irregularities, and to take new measures for maintaining high productivity by shortening the time for heating and cooling. However, the techniques of Patent Documents 2 to 4 cannot achieve such an object.

(5) Improving productivity by rapid heating / cooling In order to obtain high productivity by rapid heating / cooling, heating is achieved by using a stamper made of a thin infrared transmitting material with a thin infrared transmitting material as much as possible. It is necessary to cool quickly. However, conventionally, in order not to break a stamper made of an infrared transmitting material, which is a brittle material, by pressing, the area has to be reduced. Therefore, it is necessary to take a pressurizing means that does not break even a thin stamper with a large area, and to take a means that can rapidly heat and cool the thinner the stamper.

(6) Warp deformation When infrared rays are irradiated from the back of a stamper made of an infrared transmitting material toward a plastic substrate, the temperature of the surface irradiated with infrared rays rises, but the temperature is low on the non-irradiated surface on the opposite side. There was a problem that a temperature difference was generated between the surface and the back side of the base material, and the surface on the high temperature side was contracted by being cooled, and the plastic base material was deflected to the irradiated side. In order to solve this problem, it is necessary to appropriately heat the surface that does not irradiate infrared rays, and to take new measures that do not cause warp deformation. There was nothing.

(7) Elimination of unevenness of infrared irradiation When the plastic substrate is irradiated with infrared rays through an infrared transmitting material, the fine shape is transferred to the irradiated portion, but is not transferred to the non-irradiated portion. In addition, a pattern appears at the boundary between the irradiated part and the non-irradiated part, and the appearance of the molded product is impaired. For this reason, it is indispensable to provide a means for uniformly irradiating infrared rays in both the region where the fine unevenness of the stamper is formed and the region where the unevenness is not formed. It was not examined.
When a carbon dioxide laser that generates a wavelength of 10.6 μm as infrared rays is used, the intensity of the laser beam is not uniform within the beam cross section, and there is a beam mode that varies depending on the location as shown in FIG. For this reason, by simply irradiating the plastic substrate, according to the beam mode, a portion with high strength melts well and a portion with low strength does not melt. For this reason, strength strength appears as unevenness on the surface of the plastic substrate (irradiation unevenness), or a portion where the fine unevenness portion of the mold or stamper is not transferred and a portion where it is not transferred (transfer unevenness). The prior art has been studied only in the case of simple laser irradiation, and it is difficult to avoid irradiation unevenness and transfer unevenness. However, a method for eliminating irradiation unevenness and transfer unevenness by uniformly irradiating the entire surface of a plastic substrate with a laser beam has not been studied.

(8) Fine shape transfer on both sides of the plastic substrate In the method of using an infrared transmitting material as part of a mold or stamper and irradiating the plastic substrate with infrared rays through this, The fine irregularities formed on the surfaces of both the mold and the lower mold could not be simultaneously formed on both the front and back surfaces of the plastic substrate. However, some practical products require the simultaneous formation of fine concavo-convex shapes on both the front and back surfaces at the same time. For this purpose, it is necessary to take new measures.

(9) Stability of molding cycle In the method of using an infrared transmitting material as a part of a mold or a stamper and irradiating the plastic substrate with infrared through this, almost all of the infrared transmitting material absorbs a part of the infrared, The temperature gradually rises. In addition, when the infrared irradiation surface of the plastic substrate absorbs infrared rays and the temperature rises, the heat from the plastic substrate is transferred to the infrared transmitting material in contact with the infrared irradiation surface of the plastic substrate and the temperature rises. For this reason, in order to perform repetitive transfer in a stable molding cycle, it is necessary to cool after completion of the transfer so that the temperature of the infrared transmitting material becomes constant every molding cycle. However, in the prior art, such management of temperature conditions has not been studied at all, and has no practicality.
An object of the present invention is to solve the conventional problems as described above.

The invention according to claim 1 is a support in which a base material is mounted on the surface of a stamper made of an infrared transmitting material having a fine uneven shape on the surface, and the stamper can slide or roll on the back surface of the stamper. In the width direction of the infrared rays to the surface of the base material through the back of the stamper from a slit-like opening provided long in the width direction of the support body while pressing the base material against the stamper by a pressing means The substrate surface layer facing the stamper surface is melted linearly by linearly irradiating the stamper, and at the same time, the stamper and the substrate on the support in a direction perpendicular to the linear infrared rays. By transferring and melting and pressurizing the entire surface of the base material facing the stamper surface, the fine uneven shape of the stamper surface and the inverted uneven shape are transferred to the base material surface layer. A fine transfer method according to claim Rukoto.
According to the second aspect of the present invention, after transferring the concave and convex shape reverse to the fine concave and convex shape of the stamper surface to the base material surface layer, the stamper and the base material are cooled by a cooling means, and then the peeling means is used. The fine transfer method according to claim 1, wherein the stamper and the substrate are peeled off.
A third aspect of the present invention is the fine transfer method according to the first or second aspect, wherein the width, height and depth of the fine uneven shape are in the range of 1 nm to 1 mm.
The invention according to claim 4 is the fine transfer method according to claim 1 or 2, wherein the substrate is a solid thermoplastic resin or a molten thermoplastic resin.
The invention according to claim 5 is the fine transfer method according to claim 1 or 2, wherein the substrate has a glass transition temperature of −125 to 290 ° C.
The invention according to claim 6 is a stamper made of an infrared transmitting material having a fine uneven shape on the surface ;
From the back surface of the stamper, an infrared light source for irradiating the base material attached to the stamper with infrared light;
Provided between the stamper and the infrared light source, supports the back surface of the stamper and supports the stamper so that it can slide or roll, and infrared rays emitted from the infrared light source are linearly formed on the back surface of the stamper. A support having a slit-like opening that is long in the width direction of the stamper so as to be irradiated;
Pressurizing means for pressing the substrate against the stamper;
Moving means for moving the stamper, the base material, and the pressing means together in a direction perpendicular to the width direction;
Heating means for heating the stamper and the substrate;
Cooling means for cooling the stamper and the substrate;
A fine transfer device having a peeling means for peeling the substrate from the stamper,
A slit-like opening provided in the support while mounting the base on the surface of the stamper, supporting the back of the stamper with the support, and pressing the base against the stamper by the pressurizing means The substrate surface layer facing the stamper surface is melted linearly by irradiating the surface of the substrate linearly in the width direction through the back of the stamper from the portion, and at the same time, the stamper by the moving means, The base material and the pressing means are integrated and moved in a direction perpendicular to the width direction, and the whole surface layer of the base material facing the stamper surface is melted and pressed, thereby reversing the fine uneven shape of the stamper surface. The concavo-convex shape to be transferred is transferred to the substrate surface layer, and then the stamper is cooled by the cooling unit, and the substrate and the stamper are separated by the peeling unit. A fine transfer apparatus characterized by peeling.
The invention according to claim 7 includes an upper stamper having a fine uneven shape on the surface and a lower stamper made of an infrared transmitting material having a fine uneven shape on the surface;
A lower mold and an upper mold for fixing the lower mold stamper and the upper mold stamper ;
An infrared light source provided on the back side of the lower stamper;
An infrared light source for irradiating infrared rays on a base material provided on the back side of the lower mold stamper and sandwiched between the upper mold stamper surface and the lower mold stamper surface ;
Provided between the lower mold stamper and the infrared light source, supports the lower mold stamper and supports the lower mold stamper to be slidable or rollable, and infrared rays emitted from the infrared light source are emitted from the lower light source. A lower stamper support having a slit-like opening that is long in the width direction of the lower stamper so that the back surface of the mold stamper is linearly irradiated;
A pressing means for pressing the base material against the upper stamper;
Moving means for moving the lower mold stamper, the upper mold stamper, the base material, the upper mold, the lower mold and the pressurizing means together in a direction perpendicular to the width direction;
Heating means provided on the upper mold, lower mold and / or lower mold stamper support for heating the upper mold stamper and the lower mold stamper;
Cooling means provided on the upper mold, lower mold and / or lower mold stamper support for cooling the upper mold stamper and the lower mold stamper;
A peeling means provided on the upper die, the lower die and / or the lower die stamper support for peeling the substrate from the lower die stamper and the upper die stamper,
The lower mold stamper fixed to the lower mold is supported so that it can slide or roll, and the upper mold with the upper mold stamper fixed is fixed to the pressing means, and in this state, the upper mold stamper While the lower stamper is heated by the heating means, the substrate is attached to the surface of the lower mold stamper, and the substrate is pressed by the upper mold stamper by the pressing means, and at the same time, the substrate by the moving means The lower mold stamper, the lower mold stamper, the upper mold, the lower mold and the pressurizing means are moved together in the direction perpendicular to the width direction, and the infrared rays are transmitted through the opening provided in the lower mold stamper support. By irradiating the back surface of the mold stamper linearly, the surface of the base material in contact with the lower mold stamper is irradiated with infrared light on the surface of the lower mold stamper that is reversed with the fine irregular shape of the surface of the lower mold stamper. The heating means is formed by heat-melting by irradiation, heat-melting by the heating means, and pressurization, and a fine uneven shape that reverses the fine uneven shape of the upper stamper surface on the surface that contacts the upper stamper of the base material The upper stamper and the lower mold stamper are cooled by the cooling means, and then the base material and the upper mold stamper and the lower mold stamper are peeled by the peeling means. This is a fine transfer device.
The invention according to claim 8 includes a lower mold stamper and an upper mold stamper each having a fine uneven shape on the surface and made of an infrared transmitting material,
A lower mold and an upper mold for fixing the lower mold stamper and the upper mold stamper ;
An infrared light source for irradiating infrared rays on a base material provided on the back surface of the lower mold stamper and the upper mold stamper, and sandwiched between the upper mold stamper surface and the lower mold stamper surface ;
Provided between the lower mold stamper and the upper mold stamper and the respective infrared light sources, support the lower mold stamper and the upper mold stamper, and allow the lower mold stamper and the upper mold stamper to slide or roll. A slit-like opening that is long in the width direction of the lower mold stamper and the upper mold stamper so that infrared rays emitted from the infrared light source are linearly irradiated to the lower mold stamper rear surface and the upper mold stamper rear surface. A lower stamper support and an upper stamper support with a portion,
A pressing means for pressing the base material against the upper stamper;
A moving means for integrally moving the lower mold stamper, upper mold stamper, base material, upper mold and lower mold in a direction perpendicular to the width direction;
Heating means provided on the upper mold, lower mold, lower mold stamper support and / or upper mold stamper support for heating the upper mold stamper and lower mold stamper;
Cooling means provided on the upper mold, the lower mold, the lower mold stamper support and / or the upper mold stamper support for cooling the upper mold stamper and the lower mold stamper,
A fine transfer apparatus comprising: an upper mold, a lower mold, a lower mold stamper support and / or a peeling means provided on the upper mold stamper for peeling the base material from the lower mold stamper and the upper mold stamper. There,
The lower mold stamper support and the upper mold stamper support are fixed to the pressurizing means, and the lower mold stamper is fixed to the lower mold so that the lower mold stamper can slide or roll. The upper mold is supported on a stamper support, and the upper mold fixed with the upper mold stamper is supported on the upper mold stamper support so that the upper mold stamper can slide or roll. While the mold stamper and the lower mold stamper are heated by the heating means, the base material is mounted in the gap between the lower mold stamper surface and the upper mold stamper surface, and the upper mold stamper and the lower mold are formed by the pressurizing means. At the same time as pressing with a stamper, the moving means moves the base material, upper mold stamper, lower mold stamper, upper mold and lower mold together in a direction perpendicular to the width direction. However, the lower mold stamper of the substrate is irradiated with infrared rays linearly on the lower mold stamper rear surface and the upper mold stamper rear surface through openings provided in the lower mold stamper support body and the upper mold stamper support body. And the surface of the lower mold stamper and the surface of the upper mold stamper on the surface contacting the upper mold stamper are formed by heating and melting by infrared radiation, heating and melting by the heating means and pressurization. Thereafter, the upper stamper and the lower mold stamper are cooled by the cooling means, and the substrate and the upper mold stamper and the lower mold stamper are peeled off by the peeling means.
The invention according to claim 9 is the heating part, the heat insulating part, the cooling part, and the stamper vacuum adsorbing part in the order in which the support or upper stamper support and / or lower stamper support moves in the direction in which the stamper moves. The fine transfer device according to claim 6, wherein
The invention described in claim 10 is characterized in that a part of the stamper, the upper stamper or the lower stamper is formed of FZ silicon which transmits infrared light having a wavelength of 10.6 μm for 40% or more. The fine transfer device according to any one of 6 to 8.
The invention according to claim 11 is the infrared transmitting material in which at least a part of the stamper or upper stamper or lower stamper is selected from FZ silicon, ZnSe, ZnS, Ge, NaCl, BaF ₂ , KBr and CaF _2. Alternatively, the fine transfer device according to any one of claims 6 to 8, wherein the fine transfer device is formed from a combination thereof.
The invention according to claim 12 is the fine transfer device according to claim 7 or 8, wherein at least a part of the upper mold stamper and the lower mold stamper is formed by Ni electroforming.
The invention according to claim 13 is the fine transfer apparatus according to any one of claims 6 to 8, wherein the infrared light source is an infrared lamp, a carbon dioxide laser, or a YAG laser.
In the invention described in claim 14, the infrared ray emitted from the infrared light source is linearly generated by a swing mechanism using a polygon mirror, a galvano scanner, a stepping motor or an AC servo motor, a beam expander, a cylindrical lens or a homogenizer. 7. The beam is deformed, and the linear beam passes through a slit-like opening provided in the width direction of the support, the upper stamper support, or the lower stamper support. The fine transfer device according to any one of -8.
According to a fifteenth aspect of the present invention, the thickness of the stamper or the upper mold stamper or the lower mold stamper is 0.3 mm to 30 mm. The fine transfer apparatus according to any one of the sixth to eighth aspects, It is.
The invention according to claim 16 is characterized in that at least a part of the surface of the lower stamper support in contact with the support and the lower surface of the lower stamper and the surface of the upper stamper support in contact with the upper surface of the upper stamper is a low friction sliding bearing, The fine transfer device according to any one of claims 6 to 8, wherein the fine transfer device is formed by a rolling bearing or a conveyor.
According to a seventeenth aspect of the present invention, the heating means includes a heater for the lower mold, the lower stamper support, the upper mold and / or the upper stamper support, and a thermocouple for temperature control. The fine transfer device according to claim 7 or 8, wherein
According to an eighteenth aspect of the present invention, the cooling means includes a water cooling pipe provided on the lower mold, the lower stamper support, the upper mold and / or the upper stamper support, and a thermocouple for temperature control. The fine transfer device according to claim 7 or 8, wherein
According to a nineteenth aspect of the present invention, the peeling means includes a vacuum suction hole, an air outlet hole, a protruding pin, a rapid cooling provided in the upper mold, the lower mold, the upper stamper support and / or the lower stamper support. 9. The fine transfer device according to claim 7, wherein the fine transfer device comprises a water / air pipe or a rapid cooling Beltier element.

  According to the present invention, while pressing the base material against the stamper and irradiating the stamper with a linear infrared beam, the base material is in contact with the stamper by moving in the longitudinal direction while the base material and the stamper are fixed. By melting and expanding the surface layer, it is possible to perform pressure transfer while sequentially removing the air remaining in the fine uneven shape of the stamper, thus eliminating the obstruction of the transfer of the fine uneven shape due to the remaining air. Sufficient transfer is possible even at an extremely low pressure of 1 MPa or less. As a result, the residual stress and birefringence do not remain on the base material, and a molded article having excellent optical characteristics can be obtained. In addition, since the infrared rays can be uniformly irradiated on the entire surface of the substrate and unevenness due to uneven irradiation can be eliminated, a good transfer surface can be obtained over a large area with a side length of several centimeters to several tens of centimeters. Moreover, as a stamper for irradiating infrared rays, most of them are fragile materials such as infrared transmissive materials, for example, FZ silicon whose infrared transmittance decreases with thickness (50% at 0.5mm thickness, 43% at 1mm thickness, thickness) Using materials such as 9% at 5mm) and Ge (47% at 1mm thickness, 46% at 5mm thickness, 45% at 10mm thickness), etc., and using a thin stamper of about 0.3-1mm, Almost no bending is applied to the stamper, and therefore there is no breakage due to bending. As a result, an extremely thin and inexpensive infrared transmitting material can be used. In addition, a heating part for heating and cooling the stamper and the substrate, and a cooling part are provided independently, and a thin stamper with a small heat capacity can be used, so the transition from heating to cooling of the stamper can be performed quickly. Therefore, the substrate can be heated and cooled in an extremely short time, and high productivity can be obtained. According to the embodiment in which the temperatures of the upper mold stamper and the lower mold stamper are controlled independently, the thermal stress due to thermal contraction in the cooling process of the surface irradiated with infrared rays and the surface not irradiated with the base material can be controlled. The warp deformation of the material can be eliminated. Furthermore, in the form of transferring the fine irregularities on both the front and back surfaces of the base material, since the infrared radiation is simultaneously applied to both the front and back surfaces of the base material, transfer is performed. It becomes possible, and it becomes possible to produce a fine uneven product having a large area on both the front and back surfaces with high productivity. In addition, by repeatedly performing heating, cooling, and mold release processes continuously, production in a stable molding cycle becomes possible. Furthermore, the base material and the stamper can be easily separated from each other by the temperature control and rapid cooling of the stamper and the base material.

Hereinafter, embodiments of the present invention will be further described with reference to the drawings.
FIG. 1 is a view for explaining an apparatus for carrying out the fine transfer method of the present invention. FIG. 1A is a front view of the apparatus, and FIG.
The substrate used in the present invention is not particularly limited as long as it is a material that absorbs infrared rays and its surface layer can be melted. Examples thereof include plastics and low-melting glass, but the following are plastics suitable for the present invention. The form which used as a base material is demonstrated. In FIG. 1, a lower stamper 1L having a fine uneven shape 1Lc is FZ silicon having a thickness of 0.3 to 1 mm, and transmits 40% or more of infrared rays having a wavelength of 10.6 μm. The fine concavo-convex shape has, for example, a width, height and depth in the range of 1 nm to 1 mm. The plastic substrate 2 is mounted on the surface 1La of the lower mold stamper 1L. The thickness of the plastic substrate 2 is 50 μm to several mm. The plastic substrate 2 is not particularly limited as long as it absorbs infrared rays, such as acrylic resin, polycarbonate resin, cyclic olefin resin, polystyrene, and PET resin, but a thermoplastic resin having a glass transition temperature of −125 to 290 ° C. preferable. The plastic substrate 2 to be mounted on the lower mold stamper 1L may be mounted on the lower mold stamper 1L by applying a molten thermoplastic resin in addition to the solid state. The lower mold stamper 1L is placed on the lower mold stamper support 5L. The upper die 12U is provided with an electric heater as the heating means 9, a water pipe as the cooling means 10, and a mechanical ejector as the release means 11. The pressing means 6 pressurizes the upper mold 12U toward the plastic substrate 2 and presses the plastic substrate 2 against the lower mold stamper 1L. The lower stamper support 5L is provided with a slit-like opening 8 that is long in the width direction 7, and a beam-like infrared ray 3 is irradiated from below to oscillate the oscillating mirror 16 by linear irradiation. The lower stamper 1L is irradiated linearly through the opening 8. In the above configuration, pressure is applied while irradiating the back surface 1Lb of the lower mold stamper 1L with the linear infrared rays 3 while pressing the plastic substrate 2 against the lower mold stamper 1L by the pressing means 6 through the heated upper mold 12U. The means 6, the upper mold 12U, the plastic substrate 2 and the lower mold stamper 1L are moved together in the longitudinal direction 4. As a result, the infrared ray 3 is uniformly irradiated on the entire transfer surface as a product including the fine uneven shape on the plastic substrate 2, and the surface irradiated with the infrared ray 3 is melted to form the fine uneven shape of the lower mold stamper 1L. The concavo-convex shape to be reversed is formed on the plastic substrate 2. Here, the lower mold stamper 1L and the lower mold stamper support 5L are formed to be slidable or rollable with each other. In the case of sliding, the sliding portion of the lower mold stamper support is made of Teflon resin, Teflon. It is made of coating alloy and other low friction plain bearings. In the case of rolling, it is formed by a rolling bearing or a conveyor. A conveyor having a predetermined flatness may be used. The lower stamper support 5L is formed with a linear opening 8 having a very narrow width of about 1 cm. Even if the stamper is pressed against this portion, the stamper is hardly bent. For this reason, even if the lower mold stamper 1L made of an infrared transmitting material, which is a brittle material, is thin, it does not break due to bending. Subsequently, as shown in FIG. 2A, the lower stamper 1L passes through the heating part 5LH, the heat insulating part 5LI, and the cooling part 5LC of the lower stamper support 5L as shown in FIG. 2B. The lower mold stamper 1L is adsorbed to the support at the vacuum adsorption site 5LV, and in this state, the upper mold 12U is opened as shown in FIG. Is released (FIG. 3B).

Actually, FZ silicon having a diameter of 3 inches and a thickness of 0.5 mm is used as an infrared transmitting material, and a 50 μm square lattice and a line and space formed at a pitch of 5 μm up to 5 to 50 μm on this FZ silicon. A part of the lower mold stamper 1L processed to 10 μm is shown in FIG. The lower stamper 1L is used, the lower stamper support 5L is kept at room temperature, the cooling is naturally allowed to cool, the carbon dioxide laser output is 55 W, and a beam diameter having a sufficient intensity (1 / e ² at which the beam intensity reaches its peak). The beam diameter was set to φ7 mm, and the back surface 1Lb of the lower mold stamper 1L was irradiated in the width direction 7. As the plastic substrate 2, a solid acrylic resin having a width of 4 cm, a length of 5 cm, and a thickness of 3 mm was used. The frequency of the oscillating mirror 16 for forming the linear beam was 1 Hz, and the width of the irradiated linear beam was 5 cm. The plastic substrate 2, the lower mold stamper 1L, the pressing means 6, and the upper mold 12U are integrally moved in the longitudinal direction 4 at a speed of 5 mm / s, moved 6 cm in the longitudinal direction 4 and then moved 6 cm in the opposite direction. . That is, the linear beam was irradiated while the plastic substrate 2 was reciprocated once. Although the applied pressure can be 0.1 MPa to 10 MPa, it is set to 0.1 MPa in this embodiment. The irradiation time is (60 mm / 5 mm / s) × 2 = 24 seconds. In the case of 55 W laser output, the energy transmitted through the FZ silicon was 28 W. For this reason, the irradiation density was 28 W / (0.7 ² · π / 4) = 72 W / cm ² . In this state, as shown in FIG. 5, when a linear beam is formed at a frequency of 1 Hz with a width of 5 cm (amplitude) while moving the stamper 7 cm in the longitudinal direction 4 at 5 mm / s, a sufficient beam intensity is 7 mm. Therefore, according to the irradiation profile represented by the solid line 20, the plastic substrate 2 has no region not irradiated with the laser beam, and the entire surface of the acrylic resin of 4 cm × 5 cm is uniformly irradiated with the laser beam. become. That is, as shown in FIG. 5, when the beam swing mechanism is used, the laser beam reciprocates and stops at both ends of the amplitude for a very short time. The irradiation energy becomes non-uniform at both ends and other portions, and the surface of the plastic substrate is likely to be uneven due to uneven irradiation. For this reason, as shown in FIG. 5, it is important to uniformly irradiate the entire surface of the product region of the plastic substrate 2 in the region excluding both ends where the beam stops for a very short time. As a result, the fine uneven shape formed on the 4 cm × 5 cm acrylic plastic substrate is shown in FIG. The fine concavo-convex shape of FZ silicon shown in FIG. 4 and the inverted concavo-convex shape were obtained at a transfer rate of approximately 100% (the concavo-convex height of the transfer body / the concavo-convex height of the stamper). Moreover, it became the smooth plane similar to FZ silicon | silicone except the fine uneven | corrugated shaped surface. From the above, the depth can be increased by simply irradiating the carbon dioxide laser for 28 seconds while applying pressure at an extremely low pressure of 0.1 MPa without heating and cooling the upper mold 12U, the lower mold stamper 1L, and the lower mold stamper support 5L. A line and space of 5 to 50 μm at 10 μm, a 50 μm square lattice at the same depth could be transferred sufficiently, and an extremely good surface property could be obtained.

7 and 8 are views for explaining another embodiment of the fine transfer apparatus of the present invention. FIG. 7 is a front view of the apparatus, and FIG. 8 is a side view. The apparatus shown in FIGS. 7 and 8 has substantially the same configuration as the apparatus of FIG. 1 described above, but a lower mold stamper 1L made of an infrared transmitting material is fixed to the lower mold 12L, and a Ni electric power is connected to the upper mold 12U. An upper die stamper 1U made of cast and having a surface 1Ua is fixed, and a moving means 14 for moving the pressurizing means 6, upper die 12U, lower die 12L, upper die stamper 1U and lower die stamper 1L integrally in the longitudinal direction. Is different.
First, as shown in FIG. 8, the plastic substrate 2 is fixed on the lower mold stamper 1L in a state where the upper mold 12U and the lower mold stamper support 5L are heated.

FIG. 18 is a diagram illustrating a state where a lower mold stamper 1L having a fine uneven shape 1Lc is fixed to the lower mold 12L. 18A is a plan view, FIG. 18B is a sectional view, and FIG. 18C is a bottom view. FZ silicon having a diameter of 3 inches and a thickness of 0.5 to 1 mm is used as the lower stamper 1L. This is fixed by a lower mold having a square frame for loading the plastic substrate 2. Here, in addition to FZ silicon, Ge, ZnSe, ZnS, NaCl, BaF ₂ , KBr, CaF ₂ or the like may be used as the lower stamper 1L.

  Next, as shown in FIG. 9, the upper die 12U is closed by the pressing means 6, and the plastic substrate 2 is pressed against the lower die stamper 1L by pressing the plastic substrate 2 with the upper die 12U. Preheat is applied to the plastic substrate 2. Here, preheating is performed when the area of the plastic substrate 2 is large in order to improve the adhesion between the lower mold stamper 1L and the plastic substrate 2, and by heating the upper mold stamper 1U, the plastic substrate 2 This is because the fine uneven shape of the surface 1Ua of the upper stamper is transferred to the upper surface of the upper mold. The upper mold 12U is heated around the glass transition temperature of the plastic substrate 2. About the lower mold | type stamper 1L, the minimum heating for improving the adhesiveness with the plastic base material 2 may be sufficient.

  In this state, as shown in FIG. 10, the pressing means 6, the upper mold 12U, the lower mold 12L, the upper mold stamper 1U, the lower mold stamper 1L, and the plastic substrate 2 are integrated in the longitudinal direction by the moving means 14. 4, the infrared rays 3 are irradiated linearly toward the back surface of the lower mold stamper 1 </ b> L through the slit-shaped opening 8 long in the width direction 7 provided in the lower mold stamper support 5 </ b> L. The entire lower mold stamper 1L is uniformly irradiated with the infrared rays 3 and, as shown in FIG. 5, the entire surface of the plastic substrate 2 is irradiated with no irradiation unevenness. In addition, as shown in FIG. 11, the transfer rate of the fine uneven shape by infrared irradiation may be ensured by reciprocating several times to the left and right in the longitudinal direction. As described above, since the opening 8 has a very narrow slit shape, even if the lower mold stamper 1L is pressed against this portion, the lower mold stamper 1L is hardly bent and the lower mold stamper is made of a thin brittle material. Even if there is, there is no breakage due to bending.

  When these are completed, as shown in FIG. 12, the pressure means 6 and the heating means 9 are used for heating while appropriately adjusting the applied pressure to eliminate the difference in shrinkage between the front and back surfaces of the plastic substrate 2 and warp deformation. To prevent.

When the forming is completed as described above, as shown in FIG. 13, the pressing means 6, the upper mold 12U, the lower mold 12L, the upper mold stamper 1U, the lower mold stamper 1L and the plastic substrate 2 are integrated by the moving means 14. As described above, by moving to the adjacent cooling part 5LC through the heat insulating part 5LI of the lower mold stamper support 5L, the fine mold surface of the lower mold stamper 1L and the plastic substrate 2 in contact therewith is rapidly cooled. Since the lower stamper can be made very thin, rapid cooling becomes possible. Further, as shown in FIG. 14, the back side of the lower stamper 1L is vacuum-sucked by a vacuum pump (not shown) from the vacuum suction part 5LV to prepare for mold release. Then, as shown in FIG. 15, when the upper die 12U is opened by the pressurizing means 6, the plastic substrate 2 attached to the upper die stamper 1U rises simultaneously with the upper die stamper 1U, and the lower die stamper 1L and the plastic substrate The material 2 peels off. This is because the upper mold stamper 1U and the plastic substrate 2 are bonded to each other by controlling the temperature of the upper mold stamper to be slightly higher than that of the lower mold stamper 1L. This is done by making it larger than the adhesive force. If FZ silicon, which has a low linear expansion coefficient of 2.6 × 10 ⁻⁶ ° C. ⁻¹ and is an infrared transmitting material, is used for the lower stamper, the difference from the linear expansion coefficient with the plastic substrate 2 becomes very large ( For example, the linear expansion coefficient of acrylic resin is 50 to 90 × 10 ⁻⁶ ° C. ⁻¹ ), and the temperature from the molding temperature to the mold release temperature as the temperature of the lower mold stamper 1L and the plastic substrate 2 decreases. The difference in the amount of heat shrinkage corresponding to the descending amount becomes large, and as a result, a peeling force is generated between the lower mold stamper 1L and the plastic substrate 2 due to the slip deformation, and the peeling becomes easy. On the other hand, if Ni electroforming is used for the upper die stamper 1U, the linear expansion coefficient of Ni is 13.4 × 10 ⁻⁶ ° C. ^−1. Since the difference in expansion coefficient is small, even if the upper mold stamper 1U and the lower mold stamper 1L are at the same temperature, the peeling force between the upper mold stamper 1U and the plastic substrate 2 is higher than that of the lower mold stamper 1L. Get smaller. For this reason, it becomes easy to adhere to the upper mold stamper. Contrary to the above, the lower stamper 1L may be made of Ni, the upper stamper 1U may be made of FZ silicon, and infrared rays may be irradiated through the back surface of the upper stamper.

  Next, as shown in FIG. 16, the plastic substrate 2 is ejected by a mechanical ejector which is a release means 11 incorporated in the upper die 12U, and the molding is completed. As shown in FIG. Then, the upper mold stamper 1U and the lower mold stamper 1L are cleaned. By repeating the above molding cycle, it becomes possible to continuously produce the plastic substrate 2 having fine irregularities on the front and back surfaces. Using this fine transfer apparatus, a molded product having a diameter of 180 mm could be manufactured using FZ silicon as an infrared transmitting material having a thickness of 0.5 to 1 mm and a diameter of 8 inches. Further, if a large-diameter FZ silicon is used, a larger molded product can be produced.

FIG. 19 is a view for explaining another embodiment of the fine transfer apparatus of the present invention. FIG. 19 shows a front view of the device. Note that the symbols have the same meaning as in the above drawings. FIG. 19 shows an implementation of an apparatus for giving a fine uneven shape by irradiating infrared rays 3 on both the front and back surfaces of a plastic substrate 2 using an infrared transmitting material for both the upper die 1U and the lower die 1L. It is an example. Both the upper stamper 1U and the lower stamper 1L were made of FZ silicon, which is an infrared transmitting material having a thickness of 0.5 to 1 mm.
For the upper mold 12U, ZnSe having an infrared transmittance of 90% or more even with a thickness of 10 mm or more was used. A lower mold stamper 1L, a plastic substrate 2, an upper mold stamper 1U, and an upper mold 12U were stacked on the lower mold stamper support 5L, and these were loaded into the lower mold 12L. The oscillating mirror 16 was formed on the back surface of the lower stamper support 5L and the upper stamper support 5U of the pressurizing means 6. A laser beam emitted from the carbon dioxide laser 13 is split up and down via a beam splitter 17, passed through a fixed mirror 18, and then on a back surface 1 Ub of the upper mold stamper 1 U and a back surface 1 Lb of the lower mold stamper 1 L via a swing mirror 16. It was set as the structure irradiated linearly.

  As shown in FIGS. 20 and 21, the upper die stamper support 5U is closed by the pressing means 6 to pressurize the upper die 12U, and the plastic substrate 2 is pressed by the upper die stamper 1U and the lower die stamper 1L. At the same time, while irradiating the laser beam 3 emitted from the carbon dioxide laser 13 through the oscillating mirror 16 from the back surfaces of the upper mold stamper 1U and the lower mold stamper 1L toward the plastic substrate 2, in a linear manner, By moving the upper die stamper 1U, the lower die stamper 1L, the upper die 12U, the lower die 12L, and the plastic base material 2 in the longitudinal direction 4 by the moving means 14, fine unevenness caused by infrared irradiation on both front and back surfaces of the plastic base material Form the shape. The molding cycle is the same as that shown in FIGS. Reference numerals 5UH, 5UI, 5UC, and 5UV are a heating part, a heat insulating part, a cooling part, and a vacuum adsorption part, respectively. Like the reference signs 5LH, 5LI, 5LC, and 5LV, rapid heating of the upper stamper, It is provided for cooling and easy mold release. As described above, a plastic base material having a smooth surface property that has fine irregularities on both the front and back surfaces and is free of irradiation unevenness on both front and back surfaces in an extremely short time while irradiating infrared light uniformly on both the upper and lower surfaces. I was able to get it.

FIG. 22 shows a rectangular plastic substrate 2 fixed on a lower mold 12L and a lower mold stamper 1L made of an infrared transmitting material having a fine irregular shape on the surface, and infrared rays 3 are drawn from the back surface of the lower mold stamper 1L. The lower surface of the lower stamper when the plastic substrate 2, the lower mold 12L and the lower mold stamper 1L are moved together in the longitudinal direction 4 while pressing the plastic substrate 2 against the lower mold stamper 1L The state seen from. In order to uniformly heat and melt the surface of the plastic substrate 2 having a fine uneven shape to transfer the fine uneven shape and obtain a smooth surface property free from irradiation unevenness, as shown in FIG. Irradiation is necessary so that the beam width and the irradiation distance in the longitudinal direction are larger than the width and length of the plastic substrate. In the intensity distribution of the laser beam, if the diameter at which the beam intensity of the infrared ray 3 is 1 / e ² times the maximum intensity is φB and the width W and the length L of the plastic substrate are set,
Linear beam deflection width WB> W + φB, linear beam irradiation length LB> L + φB
Is to satisfy. This is satisfied in FIG. 5 where the width of the plastic substrate 2 × length = 4 cm × 5 cm and the beam diameter = 7 mm, whereas the linear beam deflection width × irradiation length = 5 cm × 6 cm.

  FIG. 23 is a cross-sectional view of the back surface of the lower stamper 1L while pressing the plastic substrate 2 with the fine unevenness formed on the surface of the lower stamper 1L made of an infrared transmitting material in the fine transfer method of the present invention. The state in which the air remaining in the fine uneven shape of the lower mold stamper 1L is discharged from the melted / transferred area toward the unmelted and untransferred area by irradiating infrared rays in a shape. In FIG. 23A, when infrared rays are irradiated, the irradiated resin melts and expands (reference numeral 231). By applying pressure to this, as shown in FIG. 23B, the melted and expanded resin 231 is successively filled in the fine uneven portions of the lower mold stamper 1L, and the air is not melted. Are sequentially discharged (arrow 232), and fine irregularities are smoothly transferred to the plastic substrate 2 as a whole (FIGS. 23C to 23D). As a result, the air remaining in the fine uneven shape of the lower stamper 1L does not hinder the transfer of the fine uneven shape to the plastic substrate 2, so that the surface property is smooth and at an ultra-low pressure of 1 MPa or less. In addition, transfer to the fine uneven plastic substrate 2 was possible in a short time.

In the above description, FZ silicon has been described as an example of the stamper. However, the present invention is not limited to this, and is selected from other infrared transmitting materials such as ZnSe, ZnS, Ge, NaCl, BaF ₂ , KBr, and CaF _2. It may be formed from an infrared-transmitting material that has been made or a combination thereof.
In addition to the carbon dioxide laser, the infrared light source may be an infrared lamp or a YAG laser.
Further, as a swing mechanism other than the above-described swing mirror, a swing mechanism using a polygon mirror, a galvano scanner, a stepping motor or an AC servo motor is used. As a method of forming a linear beam, a beam expander, a cylindrical lens is used. Or the method of using a homogenizer is mentioned.
The heating means may be provided on any of a lower mold, a lower stamper support, an upper mold, and an upper stamper support, and is preferably provided with a thermocouple for temperature control. Similarly, the cooling means may be provided on any of a lower mold, a lower stamper support, an upper mold, and an upper stamper support, and is preferably provided with a thermocouple for temperature control.
Further, as the peeling means, it may be provided on any of an upper mold, a lower mold, an upper stamper support, and a lower stamper support. For example, a vacuum suction hole, an air blowing hole, a protruding pin, a quick cooling water / air pipe or A rapid cooling Beltier element or the like can be used.

  In addition, although the fine transfer method and apparatus which require infrared irradiation were demonstrated above, one of the conventional subjects that the easy peeling of the plastic base material after microfabrication is difficult is, for example, FIGS. This can be overcome using the apparatus described in (1). In other words, without using infrared irradiation, a plastic base material is mounted on the surface of a stamper having a fine uneven shape on the surface, and the back surface of the stamper is supported by a support formed so as to be slidable or rollable with respect to the stamper. The entire surface of the plastic substrate facing the stamper surface is heated by the heating device while the stamper and the plastic substrate are moved together on the support while the plastic substrate is pressed against the stamper by the pressing device. By melting and pressurizing, the concave and convex shape that reverses the fine concave and convex shape on the surface of the stamper is transferred to the surface layer of the plastic substrate, and then the stamper and the plastic substrate are moved to the cooling means. Cool and then peel off the stamper and plastic substrate It is moved in stages, by separating the stamper and the plastic substrate, after application of the fine irregularities, thereby enabling easy release product. This is based on the fact that in the present invention, temperature control and rapid cooling of the stamper and the plastic substrate are possible. In other words, when the heated plastic substrate and stamper are rapidly cooled, the linear expansion coefficient of the plastic substrate is 10 times larger than that of a stamper made of silicon or nickel. In the process, a large strain rate and a corresponding shear stress are generated at the interface between the plastic substrate and the stamper, and a peeling force is generated between the plastic and the stamper. In addition, even when using an apparatus provided with an upper mold stamper, a lower mold stamper, an upper mold, a lower mold, a pressurizing means, a moving means, a heating means, a cooling means, and a peeling means as shown in FIGS. Of course, the same effect is produced.

  According to the present invention, the above-described conventional problems can be solved, and products that are markedly superior to conventional hot embossing methods, injection molding methods, compression molding methods, and nanoimprint methods can be produced with high productivity. A fine transfer method and apparatus can be provided.

It is a figure for demonstrating the apparatus for enforcing the fine transfer method of this invention. It is a figure for demonstrating the apparatus for enforcing the fine transfer method of this invention. It is a figure for demonstrating the apparatus for enforcing the fine transfer method of this invention. It is a SEM photograph of the stamper used in the embodiment. It is an infrared irradiation profile employ | adopted in embodiment. It is a SEM photograph of the fine uneven | corrugated shape of the molded article manufactured in embodiment. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure which shows the state which fixed the lower mold | type stamper 1L which has fine uneven | corrugated shape to a lower mold | type. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure for demonstrating another form of the fine transfer apparatus of this invention. It is a figure which shows the state seen from the lower mold | type and the lower mold | type stamper back surface, when a plastic base material is fixed on the lower mold | type stamper. In the fine transfer method of this invention, it is a figure which shows a mode that the air which remains in the fine uneven | corrugated shape of a lower mold | type stamper is discharged | emitted from the area | region melted | transferred and transferred toward the unmelted and untransferred area | region. It is a figure for demonstrating the beam intensity distribution of a carbon dioxide gas laser.

Explanation of symbols

  1L: lower mold stamper, 1La: lower mold stamper surface, 1Lb: lower mold stamper back surface, 1Lc: fine uneven shape of lower mold stamper, 1U: upper mold stamper, 1Ua: upper mold stamper surface, 1Ub: upper mold stamper back surface 2: plastic substrate, 3: infrared beam, 4: longitudinal direction, 5L: lower stamper support, 5LH: heating part, 5LC: cooling part, 5LI: heat insulating part, 5LV: vacuum adsorption part, 6: pressurization Means: 7: width direction, 8: opening, 9: heating means, 10: cooling means, 11: mold release means, 12L: lower mold, 12U: upper mold, 13: infrared light source, 14: moving means, 15: Cleaning means, 16: swing mechanism, 17: beam splitter, 18: fixed mirror.

Claims (19)

  A base material is mounted on the surface of a stamper made of an infrared transmitting material having a fine uneven shape on the surface, and the back surface of the stamper is supported by a support that allows the stamper to slide or roll, While pressing the substrate against the stamper, the stamper is irradiated with infrared rays linearly in the width direction from the slit-like opening provided long in the width direction of the support through the stamper back surface to the surface of the substrate. The substrate surface layer facing the surface is melted linearly, and at the same time, the stamper and the substrate are moved on the support in a direction orthogonal to the linear infrared rays to face the stamper surface. By finely melting and pressurizing the entire surface of the base material, the fine uneven shape on the stamper surface is transferred to the base material surface layer so as to be transferred to the surface of the base material. Copy method.   After transferring the concave and convex shape reverse to the fine concave and convex shape on the surface of the stamper to the base material surface layer, the stamper and the base material are cooled by a cooling means, and then the stamper and the base material are peeled by a peeling means. The fine transfer method according to claim 1.   The fine transfer method according to claim 1 or 2, wherein a width, height, and depth of the fine uneven shape are in the range of 1 nm to 1 mm.   The fine transfer method according to claim 1 or 2, wherein the base material is a solid thermoplastic resin or a molten thermoplastic resin.   The fine transfer method according to claim 1 or 2, wherein the substrate has a glass transition temperature of -125 to 290 ° C. A stamper made of an infrared transmitting material having fine irregularities on the surface ;
From the back surface of the stamper, an infrared light source for irradiating the base material attached to the stamper with infrared light;
Provided between the stamper and the infrared light source, supports the back surface of the stamper and supports the stamper so that it can slide or roll, and infrared rays emitted from the infrared light source are linearly formed on the back surface of the stamper. A support having a slit-like opening that is long in the width direction of the stamper so as to be irradiated;
Pressurizing means for pressing the substrate against the stamper;
Moving means for moving the stamper, the base material, and the pressing means together in a direction perpendicular to the width direction;
Heating means for heating the stamper and the substrate;
Cooling means for cooling the stamper and the substrate;
A fine transfer device having a peeling means for peeling the substrate from the stamper,
A slit-like opening provided in the support while mounting the base on the surface of the stamper, supporting the back of the stamper with the support, and pressing the base against the stamper by the pressurizing means The substrate surface layer facing the stamper surface is melted linearly by irradiating the surface of the substrate linearly in the width direction through the back of the stamper from the portion, and at the same time, the stamper by the moving means, The base material and the pressing means are integrated and moved in a direction perpendicular to the width direction, and the whole surface layer of the base material facing the stamper surface is melted and pressed, thereby reversing the fine uneven shape of the stamper surface. The concavo-convex shape to be transferred is transferred to the substrate surface layer, and then the stamper is cooled by the cooling unit, and the substrate and the stamper are separated by the peeling unit. Peeling fine transfer apparatus characterized by. An upper stamper having a fine uneven shape on the surface and a lower stamper made of an infrared transmitting material having a fine uneven shape on the surface;
A lower mold and an upper mold for fixing the lower mold stamper and the upper mold stamper ;
An infrared light source provided on the back side of the lower stamper;
An infrared light source for irradiating infrared rays on a base material provided on the back side of the lower mold stamper and sandwiched between the upper mold stamper surface and the lower mold stamper surface ;
Provided between the lower mold stamper and the infrared light source, supports the lower mold stamper and supports the lower mold stamper to be slidable or rollable, and infrared rays emitted from the infrared light source are emitted from the lower light source. A lower stamper support having a slit-like opening that is long in the width direction of the lower stamper so that the back surface of the mold stamper is linearly irradiated;
A pressing means for pressing the base material against the upper stamper;
Moving means for moving the lower mold stamper, the upper mold stamper, the base material, the upper mold, the lower mold and the pressurizing means together in a direction perpendicular to the width direction;
Heating means provided on the upper mold, lower mold and / or lower mold stamper support for heating the upper mold stamper and the lower mold stamper;
Cooling means provided on the upper mold, lower mold and / or lower mold stamper support for cooling the upper mold stamper and the lower mold stamper;
A peeling means provided on the upper die, the lower die and / or the lower die stamper support for peeling the substrate from the lower die stamper and the upper die stamper,
The lower mold stamper fixed to the lower mold is supported so that it can slide or roll, and the upper mold with the upper mold stamper fixed is fixed to the pressing means, and in this state, the upper mold stamper While the lower stamper is heated by the heating means, the substrate is attached to the surface of the lower mold stamper, and the substrate is pressed by the upper mold stamper by the pressing means, and at the same time, the substrate by the moving means The lower mold stamper, the lower mold stamper, the upper mold, the lower mold and the pressurizing means are moved together in the direction perpendicular to the width direction, and the infrared rays are transmitted through the opening provided in the lower mold stamper support. By irradiating the back surface of the mold stamper linearly, the surface of the base material in contact with the lower mold stamper is irradiated with infrared light on the surface of the lower mold stamper that is reversed with the fine irregular shape of the surface of the lower mold stamper. The heating means is formed by heat-melting by irradiation, heat-melting by the heating means, and pressurization, and a fine uneven shape that reverses the fine uneven shape of the upper stamper surface on the surface that contacts the upper stamper of the base material The upper stamper and the lower mold stamper are cooled by the cooling means, and then the base material and the upper mold stamper and the lower mold stamper are peeled by the peeling means. A fine transfer device. A lower mold stamper and an upper mold stamper each made of an infrared transmitting material having a fine irregular shape on the surface;
A lower mold and an upper mold for fixing the lower mold stamper and the upper mold stamper ;
An infrared light source for irradiating infrared rays on a base material provided on the back surface of the lower mold stamper and the upper mold stamper, and sandwiched between the upper mold stamper surface and the lower mold stamper surface ;
Provided between the lower mold stamper and the upper mold stamper and the respective infrared light sources, support the lower mold stamper and the upper mold stamper, and allow the lower mold stamper and the upper mold stamper to slide or roll. A slit-like opening that is long in the width direction of the lower mold stamper and the upper mold stamper so that infrared rays emitted from the infrared light source are linearly irradiated to the lower mold stamper rear surface and the upper mold stamper rear surface. A lower stamper support and an upper stamper support with a portion,
A pressing means for pressing the base material against the upper stamper;
A moving means for integrally moving the lower mold stamper, upper mold stamper, base material, upper mold and lower mold in a direction perpendicular to the width direction;
Heating means provided on the upper mold, lower mold, lower mold stamper support and / or upper mold stamper support for heating the upper mold stamper and lower mold stamper;
Cooling means provided on the upper mold, the lower mold, the lower mold stamper support and / or the upper mold stamper support for cooling the upper mold stamper and the lower mold stamper,
A fine transfer apparatus comprising: an upper mold, a lower mold, a lower mold stamper support and / or a peeling means provided on the upper mold stamper for peeling the base material from the lower mold stamper and the upper mold stamper. There,
The lower mold stamper support and the upper mold stamper support are fixed to the pressurizing means, and the lower mold stamper is fixed to the lower mold so that the lower mold stamper can slide or roll. The upper mold is supported on a stamper support, and the upper mold fixed with the upper mold stamper is supported on the upper mold stamper support so that the upper mold stamper can slide or roll. While the mold stamper and the lower mold stamper are heated by the heating means, the base material is mounted in the gap between the lower mold stamper surface and the upper mold stamper surface, and the upper mold stamper and the lower mold are formed by the pressurizing means. At the same time as pressing with a stamper, the moving means moves the base material, upper mold stamper, lower mold stamper, upper mold and lower mold together in a direction perpendicular to the width direction. However, the lower mold stamper of the substrate is irradiated with infrared rays linearly on the lower mold stamper rear surface and the upper mold stamper rear surface through openings provided in the lower mold stamper support body and the upper mold stamper support body. And the surface of the lower mold stamper and the surface of the upper mold stamper on the surface contacting the upper mold stamper are formed by heating and melting by infrared radiation, heating and melting by the heating means and pressurization. Then, the upper mold stamper and the lower mold stamper are cooled by the cooling means, and the substrate and the upper mold stamper and the lower mold stamper are separated by the peeling means.   The support body or the upper stamper support body and / or the lower stamper support body has a heating part, a heat insulating part, a cooling part, and a stamper vacuum adsorption part in the order in which the stamper moves. The fine transfer device according to any one of 6 to 8.   9. A part of the stamper, the upper stamper, or the lower stamper is formed of FZ silicon that transmits 40% or more of infrared light having a wavelength of 10.6 μm. Fine transfer device. At least a part of the stamper or the upper stamper or the lower stamper is formed of an infrared transmitting material selected from FZ silicon, ZnSe, ZnS, Ge, NaCl, BaF ₂ , KBr and CaF ₂ or a combination thereof. The fine transfer device according to any one of claims 6 to 8, wherein   9. The fine transfer device according to claim 7, wherein at least a part of the upper mold stamper and the lower mold stamper is formed by Ni electroforming.   9. The fine transfer device according to claim 6, wherein the infrared light source is an infrared lamp, a carbon dioxide laser, or a YAG laser.   Infrared light emitted from the infrared light source is transformed into a linear beam by a swing mechanism using a polygon mirror, a galvano scanner, a stepping motor or an AC servo motor, or a beam expander, a cylindrical lens or a homogenizer. 9 passes through a slit-shaped opening provided in the width direction of the support, the upper stamper support, or the lower stamper support. Transfer device.   The fine transfer device according to any one of claims 6 to 8, wherein a thickness of the stamper or the upper mold stamper or the lower mold stamper is 0.3 mm to 30 mm.   At least part of the surface of the lower stamper support in contact with the back surface of the support and the lower stamper and the upper stamper support in contact with the back surface of the upper stamper was formed of a low friction sliding bearing, a rolling bearing or a conveyor. The fine transfer device according to any one of claims 6 to 8, wherein   The heating means includes a heater for heating on the lower die, the lower stamper support, the upper die and / or the upper stamper support, and a thermocouple for temperature control. The fine transfer apparatus according to 7 or 8.   8. The cooling means is characterized in that a water cooling pipe is provided on the lower mold, lower mold stamper support, upper mold and / or upper mold stamper support, and a thermocouple is provided for temperature control. Or the fine transfer apparatus according to 8;   The peeling means is a vacuum suction hole, an air blowing hole, a protruding pin, a rapid cooling water / air pipe or a rapid cooling Beltier element provided in the upper mold, lower mold, upper mold stamper support and / or lower mold stamper support. The fine transfer device according to claim 7, wherein the fine transfer device comprises:

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