JP2007190859A - Manufacturing method for sheet having uneven surface - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture an uneven sheet, in which a regular fine uneven pattern is formed on the surface thereof, with high quality and high productivity at a high line speed, without producing a defect. <P>SOLUTION: In this manufacturing method for the uneven sheet, the unevenness of the surface of an embossing roller 13 is transferred to and formed on the surface of the sheet W. A strip-shaped flexible sheet, which is coated with a radiation-curing resin liquid so that a resin liquid layer can be formed on a surface, is continuously traveled; the sheet is wound around the rotating embossing roller; the unevenness of the surface of the embossing roller is transferred to the resin liquid layer a radiation is applied to the resin liquid layer in a state in which the sheet is wound around the embossing roller; the sheet is separated from the embossing roller; and the uneven pattern on the surface of the sheet is brought into contact with a roller member or a supporting member in a state in which a reaction rate of the resin liquid layer reaches 70% or more. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a concavo-convex sheet, and in particular, a sheet-like material such as an embossed sheet having an antireflection effect in which a regular fine concavo-convex pattern is formed on the surface, with high quality and high quality without defects. The present invention relates to a method for producing a concavo-convex sheet suitable for production with high line speed.

  In recent years, an embossed sheet having an antireflection effect has been adopted for use in electronic displays such as liquid crystals. In addition, flat lenses such as lenticular lenses and fly-eye lenses, embossed sheets such as light diffusion sheets, brightness enhancement sheets, optical waveguide sheets, and prism sheets are used. As such an embossed sheet, a sheet having a regular fine concavo-convex pattern formed on the surface has been conventionally known. As a method for forming such a regular fine uneven pattern, various methods are conventionally known (see Patent Documents 1 to 7).

  For example, in an apparatus configured as shown in FIG. 6, a resin is applied to the surface of the stamper roller 1 having a regular uneven pattern formed on the surface by the applying means 2, and the continuously running sheet 3 is applied to the stamper roller. 1 and the nip roller 4, the resin of the stamper roller 1 is in contact with the sheet 3, the resin is irradiated with ionizing radiation and cured, and then the sheet 3 is wound around the release roller 5 and peeled off from the stamper roller 1. The content to be made is disclosed (see Patent Documents 1 to 3).

  Further, in the apparatus configured as shown in FIG. 7, a resin is applied in advance to the surface of the continuously running sheet 3, and this sheet 3 is connected to the stamper roller 1 on which a regular uneven pattern is formed. Content that is sandwiched between the nip rollers 4 and the uneven pattern of the stamper roller 1 is transferred to the resin, is irradiated with ionizing radiation and cured, and then the sheet 3 is wound around the release roller 5 and peeled off from the stamper roller 1 Is disclosed (see Patent Documents 3 and 4).

  In this process, one of the important points is that the cured resin on the sheet 3 maintains a stable and highly accurate shape even after pattern formation / peeling. That is, even when a high-precision pattern can be formed at the time of peeling, the pattern is deformed due to the influence of the environment, and the surface of the patterned sheet 3 is in contact with a solid such as a roller. This is because there is a concern that the pattern shape may change.

Therefore, after the pattern formation, it is impossible to make the change of the fine uneven pattern completely zero, but even if there is deformation, keep the embossed sheet stably to keep it below a certain limit, and also suppress deformation as much as possible Desirable to.
JP-A-11-262958 JP-A-11-300768 JP 2001-314815 A JP 2002-67057 A JP 2000-221870 A JP 2003-241393 A JP 2004-160843 A

  However, in the conventional proposal regarding such an embossed sheet, there is no mention of means for maintaining the cured pattern surface until it comes into contact with the roller member or the solid. For example, only a means for heating after curing or irradiating radiation again to accelerate curing can be seen.

  Moreover, the proposal which prescribes | regulates the reaction rate of a radiation curable resin in the manufacturing process of such an embossed sheet is also seen (refer patent document 5, 6). Among these, Patent Document 5 discloses a method of pre-irradiating the resin so that the reaction rate of the resin is 20 to 70%, then pressing the concave and convex pattern plate, and then performing post-irradiation so that the reaction rate of the resin is 80% or more. Adopted. Patent Document 6 stipulates that the double bond remaining rate of the cured resin is 1 to 25% (reaction rate is 75 to 99%) in the formation of the lens sheet.

  However, these proposals do not stipulate the reaction rate or the remaining rate when the surface of the patterned sheet 3 comes into contact with a solid such as a roller. Absent.

  In addition, as a related art, there is a proposal to prevent a change in pattern shape by managing the temperature and humidity within a predetermined range when forming a partition such as a plasma display as in Patent Document 7, but only with this method, The problem cannot be dealt with.

  The present invention has been made in view of such circumstances, and is used to manufacture a concavo-convex sheet having a regular fine concavo-convex pattern formed on the surface with high quality and high productivity without defects. An object of the present invention is to provide a method for producing a concavo-convex sheet suitable for the above.

  In order to achieve the above object, the present invention provides a method for producing a concavo-convex sheet in which the concavo-convex surface of the concavo-convex roller is transferred and formed on the surface of the sheet-like body. A belt-like flexible sheet-like body in which a liquid layer is formed is continuously run, the sheet-like body is wound around the rotating uneven roller, and the unevenness on the surface of the uneven roller is transferred to the resin liquid layer, The resin liquid layer is irradiated with radiation in a state where the sheet-like body is wound around the uneven roller, the sheet-like body is peeled off from the uneven roller, and the reaction rate of the resin liquid layer is 70% or more. Provided is a method for producing a concavo-convex sheet, wherein the concavo-convex pattern on the surface of the sheet-like body is brought into contact with a roller member or a support member.

  According to the present invention, in the method for producing a concavo-convex sheet in which the concavo-convex surface of the concavo-convex roller is transferred and formed on the surface of the sheet-like body, the concavo-convex roller is transferred to the radiation-cured resin layer and irradiated with radiation in that state. The concavo-convex pattern on the surface of the sheet-like body is brought into contact with the roller member or the support member in a state where the separation is further performed and the reaction rate of the resin liquid layer is 70% or more.

  That is, the present inventors removed the sheet-like body from the concavo-convex roller, and the resin liquid at the time when the concavo-convex pattern on the surface of the sheet-like body is brought into contact with the roller member (guide roller etc.) or the support member (guide bar etc.) downstream. Paying attention to the reaction rate of the layer, it was found that if the reaction rate of the resin is 70% or more, there is no problem even if the uneven pattern on the surface of the sheet-like body is brought into contact with the roller member or the support member.

  This is because, as a matter of course, if the concavo-convex pattern surface comes into contact with the roller member or the support member, the concavo-convex portion is likely to be crushed due to the contact pressure. Then, by setting a certain time after mold release, curing (reaction) proceeds and the uneven pattern is difficult to deform.

  Therefore, according to the present invention, a concavo-convex sheet having a regular fine concavo-convex pattern formed on the surface can be manufactured with high quality without defects and with high line speed and high productivity.

  In addition, as a resin reaction rate which does not have a problem when a fine uneven | corrugated pattern surface contacts a roller member or a supporting member, 75% or more is more preferable, and 80% or more is still more preferable.

  Further, in this specification, the “concave / convex roller” refers to a concavo-convex pattern (embossed pattern on the surface of a belt-shaped body such as an endless belt as well as an embossed pattern formed on a cylindrical roller surface. In this case, even such a belt-like body acts in the same manner as a cylindrical embossing roller, and the same effect can be obtained.

  Further, the present invention provides a method for producing a concavo-convex sheet in which the concavo-convex surface of the concavo-convex roller is transferred and formed on the surface of the sheet-like body, and a resin liquid layer is formed on the surface by applying a radiation curable resin liquid. The belt-like flexible sheet-like body is continuously run, the sheet-like body is wound around the rotating concave-convex roller, the irregularities on the concave-convex roller surface are transferred to the resin liquid layer, and the sheet-like body is The resin liquid layer is irradiated with radiation while being wound around a concavo-convex roller, the sheet-like body is peeled off from the concavo-convex roller, and after 10 seconds or more has passed, the concavo-convex pattern on the surface of the sheet-like body is supported by a roller member or support. Provided is a method for producing a concavo-convex sheet characterized by contacting with a member.

  According to the present invention, the concavo-convex pattern on the surface of the sheet-like body is brought into contact with the roller member or the support member after 10 seconds or more have passed after the sheet-like body is peeled off from the concavo-convex roller. Thus, when the predetermined time elapses, curing (reaction) proceeds and the uneven pattern is difficult to deform. The predetermined time is more preferably 15 seconds or more, and further preferably 20 seconds or more.

  In the present invention, after the sheet-like body is peeled off from the uneven roller, the sheet-like body is controlled to a predetermined temperature and humidity until the uneven pattern on the surface of the sheet-like body is brought into contact with a roller member or a support member. It is preferable to place it in an open space. As described above, the transferred pattern is dried and absorbs moisture depending on the temperature and humidity. Although it is difficult to suppress this, if it is managed under a certain environment, it can be managed with the same amount of deformation, so that the product can be maintained at a certain quality.

  Moreover, in this invention, after peeling the said sheet-like body from the said uneven | corrugated roller, until the uneven | corrugated pattern of the said sheet-like body surface is made to contact with a roller member or a support member, a radiation is irradiated to the surface of the said sheet-like body It is preferable to heat the sheet-like body. Thus, if the surface of a sheet-like body is irradiated with radiation or the sheet-like body is heated (post-cure) after peeling, curing of the resin can be promoted, which is preferable.

  However, even if the curing is promoted by the post-cure after release, the concavo-convex pattern surface may be brought into contact with the roller member or the support member after a certain period of time in order to stabilize the shape. preferable.

  In the present invention, it is preferable that the radiation curable resin is an ultraviolet curable resin and the radiation is an ultraviolet ray. As the radiation curable resin, the ultraviolet curable resin is suitable for the present invention because there are many kinds and the use results are abundant.

  Moreover, in this invention, after making the uneven | corrugated pattern of the said sheet-like body surface contact with a roller member or a supporting member, it is preferable to laminate | stack a protective sheet on the surface of the said sheet-like body, and to wind up in roll shape. When the sheet-like body is wound up in a roll shape, a large pressure is applied to the uneven pattern, and there is a concern about the deformation of the uneven pattern. By thus laminating the protective sheet in advance, the uneven pattern is deformed. Can be suppressed.

  In the present invention, it is preferable that the pitch of the concavo-convex pattern transferred and formed on the sheet-like body is 100 μm or less. In the present invention, the uneven sheet is preferably used as an optical film.

  As described above, according to the present invention, a concavo-convex sheet having a regular fine concavo-convex pattern formed on the surface can be produced with high quality and high productivity without defects and with high line speed.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a configuration diagram showing a configuration of an embossed sheet manufacturing apparatus 10 to which the present invention is applied.

  The embossed sheet manufacturing apparatus 10 includes a sheet-like body supply unit 11, a coating unit 12, a drying unit 19, an embossing roller 13 that is an uneven roller, a nip roller 14, a resin curing unit 15, and a peeling roller 16. The defect inspection means 21, the protective film supply means 17, the sheet winding means 18 and the like. And the sheet | seat W which is a sheet-like body comes to be supported by the guide rollers G and G ... from an upstream side (sheet-like body supply means 11) to a downstream side (sheet winding means 18), and is conveyed. Yes.

  The sheet supply means 11 which is a sheet-like body supply means is for sending out the sheet W which is a sheet-like body, and includes a delivery roll on which the sheet W is wound.

  A first suction drum 24 is provided between the sheet supply unit 11 and the coating unit 12. The first suction drum 24 is a means for continuously running the sheet W by sucking and holding the sheet W and rotationally driving at a predetermined peripheral speed, similarly to a second suction drum 26 described later. The suction holding of the sheet W may be configured by suction from a large number of holes formed on the outer peripheral surface of the drum, or may be configured to be held by a plurality of grooves formed on the outer peripheral surface of the drum (grooved suction drum).

  A dust remover 28 is provided downstream of the first suction drum 24. The dust remover 28 can remove dust adhering to the surface of the sheet W. As the type of the dust remover 28, various known types such as a type that blows dry air that has been subjected to electrostatic dust removal and a type that winds the sheet W around an adhesive roller as shown in the figure can be adopted.

  The application means 12 is an apparatus that applies a radiation curable resin liquid to the surface of the sheet W, a liquid supply source that supplies the radiation curable resin liquid, a liquid supply apparatus (liquid feed pump) (not shown), an application The head 12C includes a support roller 12D that wraps and supports the sheet W during coating, and a pipe (not shown) for supplying a radiation curable resin liquid from a liquid supply source to the coating head 12C. As the coating head 12C, a coating head of a die coater (extrusion type coater) is employed.

  As the drying means 19, various known systems can be adopted as long as the coating liquid applied to the sheet W can be uniformly dried, such as a tunnel-shaped drying apparatus shown in FIG. 1. . For example, a radiant heating method using a heater, a hot air circulation method, a far infrared method, a vacuum method, or the like can be employed.

  The drying means 19 shown in FIG. 1 is divided into four blocks of a tunnel-like device, and is arranged in the order of the first block 19A, the second block 19B, the third block 19C, and the fourth block 19D from the upstream side. The temperature can be set individually.

  The embossing roller 13 is required to have an uneven pattern accuracy, mechanical strength, roundness, and the like that can transfer and form unevenness on the surface of the sheet W. Such an embossing roller 13 is preferably a metal roller.

  A regular fine uneven pattern is formed on the outer peripheral surface of the embossing roller 13. Such a regular fine concavo-convex pattern is required to have a shape obtained by inverting the fine concavo-convex pattern on the surface of an embossed sheet as a product. A schematic sectional view of the embossing roller 13 is shown in FIG.

  As an embossed sheet as a product, for example, a lenticular lens in which fine concavo-convex patterns are arranged two-dimensionally, or a fine cone such as a fly-eye lens, cone, or pyramid in which fine concavo-convex patterns are arranged three-dimensionally in the XY direction A flat lens or the like laid on the surface is an object, and a regular fine uneven pattern on the outer peripheral surface of the embossing roller 13 is made to correspond to this.

  As a method for forming a regular fine concavo-convex pattern on the outer peripheral surface of the embossing roller 13, a method of cutting the surface of the embossing roller 13 with a diamond bit (single point), photo-etching, electron beam drawing on the surface of the embossing roller 13, The method of forming irregularities directly by laser processing etc. can be adopted, and irregularities are formed on the surface of thin metal plate by photo etching, electron beam drawing, laser processing, stereolithography, etc. Can be wound around and fixed to the embossing roller 13.

  In addition, uneven surfaces are formed on the surface of materials that are easier to process than metal by photo-etching, electron beam drawing, laser processing, stereolithography, etc., and a reversal of this shape is formed by electroforming etc. to make a thin metal plate It is also possible to adopt a method in which an embossing roller 13 is formed by creating a body and winding and fixing the plate-like body around the roller. In particular, when the inversion mold is formed by electroforming or the like, there is a feature that a plurality of plate-like bodies having the same shape can be obtained from one master (mother).

  It is preferable to perform a mold release process on the surface of the embossing roller 13. Thus, the shape of the fine concavo-convex pattern can be satisfactorily maintained by performing the mold release process on the surface of the embossing roller 13. As the mold release treatment, various known methods such as coating treatment with a fluororesin can be employed. The embossing roller 13 is preferably provided with driving means. The embossing roller 13 rotates in the clockwise direction (CW) as shown by the arrow in the figure.

  The nip roller 14 forms a roller while pressing the sheet W while being paired with the embossing roller 13, and is required to have predetermined mechanical strength, roundness, and the like. The longitudinal elastic modulus (Young's modulus) on the surface of the nip roller 14 is set to an appropriate value because roller molding is insufficient when it is too small, and when it is too large, it reacts sensitively to the inclusion of foreign substances such as dust and tends to cause defects. It is preferable. The nip roller 14 is preferably provided with driving means. The nip roller 14 rotates counterclockwise (CCW) as shown by the arrow in the figure.

  In order to apply a predetermined pressing force between the embossing roller 13 and the nip roller 14, it is preferable to provide a pressing means on either the embossing roller 13 or the nip roller 14. Similarly, it is preferable to provide fine adjustment means on either the embossing roller 13 or the nip roller 14 so that the gap (clearance) between the embossing roller 13 and the nip roller 14 can be accurately controlled.

  The resin curing means 15 is a light irradiation means provided facing the embossing roller 13 on the downstream side of the nip roller 14. The resin curing means 15 transmits the sheet W by light irradiation and cures the resin liquid layer. The resin curing means 15 can irradiate light (radiation) having a wavelength corresponding to the curing characteristics of the resin, and according to the conveyance speed of the sheet W. It is preferable that a sufficient amount of radiation can be irradiated. As the resin curing means 15, for example, a columnar irradiation lamp having substantially the same length as the width of the sheet W can be adopted. Further, a plurality of the cylindrical irradiation lamps can be provided in parallel, and a reflector can be provided on the back surface of the cylindrical irradiation lamp. In FIG. 1, two sets of lamp houses are arranged in which cylindrical irradiation lamps are arranged inside the casing.

  The peeling roller 16 is paired with the embossing roller 13 to peel the sheet W from the embossing roller 13 and is required to have predetermined mechanical strength, roundness, and the like. The sheet W is peeled off from the embossing roller 13 and wound around the peeling roller 16 while being sandwiched between the rotating embossing roller 13 and the peeling roller 16 at the peeling portion. In order to ensure this operation, the peeling roller 16 is preferably provided with a driving means. The peeling roller 16 rotates counterclockwise (CCW) as shown by the arrow in the figure.

  In addition, when the temperature of resin etc. rises by hardening, the structure which provides a cooling means to the peeling roller 16 can also be employ | adopted in order to cool the sheet | seat W at the time of peeling, and to ensure peeling.

  Although not shown in the figure, a plurality of backup rollers are provided to face each other between the pressing location (3 o'clock position) of the embossing roller 13 and the peeling location (9 o'clock position). A configuration in which the curing process is performed while pressing the sheet W with the roller 13 can also be adopted.

  Defect inspection means 21 is disposed on the downstream side of the peeling roller 16. By such defect inspection means 21, it is possible to inspect defects in the concavo-convex pattern transferred and formed on the sheet W, and it becomes easy to eliminate defective portions. As the format of the defect inspection means 21, various known types of inspection devices (for example, CCD imaging devices) can be used.

  On the downstream side of the defect inspection means 21, a dancer roller 30 as a tension control means is arranged. The dancer roller 30 includes fixed rollers 30A and 30B and a moving roller 30C provided between the fixed rollers 30A and 30B. The tension of the sheet W is controlled by the lifting and lowering operation of the moving roller 30C.

  A second suction drum 26 is arranged on the downstream side of the dancer roller 30. As described above, the second suction drum 26 is a means for continuously running the sheet W by sucking and holding the sheet W and rotationally driving the sheet W at a predetermined peripheral speed in the same manner as the first suction drum 24. It is.

  On the downstream side of the second suction drum 26, an edge position control means (edge position controller) 32 is disposed. When the sheet W is sandwiched between the pair of fixed rollers 32A and the nip roller 32E in the first stage of the edge position control means 32, the protective film H is supplied from the protective film supply means 17 to the surface side of the sheet W. It is designed to be pinched in the overlapping state.

  The protective film supply means 17 feeds the protective film H from a roll 17A around which the protective film H is wound. The protective film H is supported by a plurality of guide rollers g, g... It is supplied to the surface of W.

  The edge position control means 32 is a device that controls the position in the width direction of the sheet W by detecting the end position in the width direction of the sheet W that is continuously running. The edge position control means 32 includes fixed rollers 32A and 32B and inclined rollers 32C and 32D provided between the fixed rollers 32A and 32B. Then, the width direction of the sheet W is controlled by the tilting operation of the tilt rollers 32C and 32D so that the position in the width direction of the sheet W becomes a normal position based on the detection result of an edge position sensor (for example, a laser type position sensor) not shown. The position is controlled.

  The sheet winding means 18 stores the peeled sheet W, and includes a winding roll that winds the sheet W or the like. In the sheet winding means 18, the sheet W is stored in the sheet winding means 18 with the protective film H overlapping the surface.

  Although not shown in FIG. 1, it is preferable to provide a temperature / humidity control unit between the peeling roller 16 and the defect inspection unit 21, or just after (downstream) the defect inspection unit 21. The temperature / humidity control means is for placing the sheet W in a space controlled to a predetermined temperature / humidity until the uneven pattern on the surface of the sheet W is brought into contact with the guide roller G1 after the sheet W is peeled off from the embossing roller 13. Device.

  Since the transferred pattern is dried and absorbed by temperature and humidity, the pattern is slightly deformed. Although it is difficult to suppress this, this temperature / humidity control means is effective in that the product can be maintained at a constant quality because it can be managed to the same deformation amount if managed in a certain environment.

  Next, each material applied to the present invention will be described. As the sheet W, a resin film, paper (resin coated paper, synthetic paper, etc.), metal foil (aluminum web, etc.) and the like can be used. As the material of the resin fill, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyester, polyolefin, acrylic, polystyrene, polycarbonate, polyamide, PET (polyethylene terephthalate), biaxially stretched polyethylene terephthalate, Known materials such as polyethylene naphthalate, polyamideimide, polyimide, aromatic polyamide, cellulose acylate, cellulose triacetate, cellulose acetate propionate, and cellulose diacetate can be used. Of these, polyester, cellulose acylate, acrylic, polycarbonate, and polyolefin can be preferably used.

  The sheet W generally has a width of 0.1 to 3 m, the sheet W has a length of 1000 to 100,000 m, and the sheet W has a thickness of 1 to 300 μm. However, application of other sizes is not impeded.

  These sheets W may be previously subjected to corona discharge, plasma treatment, easy adhesion treatment, heat treatment, dust removal treatment and the like. The surface roughness Ra of the sheet W is preferably 3 to 10 nm at a cutoff value of 0.25 mm.

  The sheet W may be a sheet W provided with a base layer such as an adhesive layer in advance and dried and cured, or a sheet having another functional layer formed in advance on the back surface. Similarly, as the sheet W, not only a one-layer structure but also a structure having two or more layers can be adopted. Moreover, it is preferable that the sheet | seat W is a transparent body and translucent body which can permeate | transmit light.

  Resins that can be used in the present invention include a reactive group-containing compound such as a (meth) acryloyl group, a vinyl group, or an epoxy group, and a radical or cation that can react with the reactive group-containing compound by irradiation with ultraviolet rays or the like. Those containing compounds that generate active species can be used.

  In particular, from the viewpoint of curing speed, a combination of a reactive group-containing compound (monomer) containing an unsaturated group such as a (meth) acryloyl group or a vinyl group and a radical photopolymerization initiator that generates a radical by light is preferable. . Of these, (meth) acryloyl group-containing compounds such as (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, and polyester (meth) acrylate are preferable.

  As the (meth) acryloyl group-containing compound, a compound containing one or more (meth) acryloyl groups can be used. Moreover, the reactive group containing compound (monomer) containing unsaturated groups, such as said acryloyl group and a vinyl group, may be used independently or may be used in mixture of multiple types as needed.

  Examples of such (meth) acryloyl group-containing compounds include, for example, isobornyl (meth) acrylate, bornyl (meth) acrylate, tricyclodecanyl as monofunctional monomers containing only one (meth) acryloyl group-containing compound. (Meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, acryloylmorpholine, 2-hydroxyethyl (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, Propyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate , Heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate , Dodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate , Butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, methoxyethylene glycol (meth) acrylate, ethoxyethyl (meth) acrylate, methoxypolyethylene glycol ( Examples include meth) acrylate and methoxypolypropylene glycol (meth) acrylate.

  Furthermore, as a monofunctional monomer having an aromatic ring, phenoxyethyl (meth) acrylate, phenoxy-2-methylethyl (meth) acrylate, phenoxyethoxyethyl (meth) acrylate, 3-phenoxy-2-hydroxypropyl (meth) acrylate, 2-phenylphenoxyethyl (meth) acrylate, 4-phenylphenoxyethyl (meth) acrylate, 3- (2-phenylphenyl) -2-hydroxypropyl (meth) acrylate, and p-cumylphenol reacted with ethylene oxide ( (Meth) acrylate, 2-bromophenoxyethyl (meth) acrylate, 4-bromophenoxyethyl (meth) acrylate, 2,4-dibromophenoxyethyl (meth) acrylate, 2,6-dibromophenoxyethyl (meth) ) Acrylate, 2,4,6-bromophenyl (meth) acrylate, 2,4,6-tribromophenoxyethyl (meth) acrylate.

  Examples of such commercially available aromatic monocyclic monocyclic monomers include Aronix M113, M110, M101, M102, M5700, TO-1317 (above, manufactured by Toagosei Co., Ltd.), Biscote # 192, # 193, # 220, 3BM (Osaka Organic Chemical Co., Ltd.), NK Ester AMP-10G, AMP-20G (Shin Nakamura Chemical Co., Ltd.), Light Acrylate PO-A, P-200A, Epoxy Ester M-600A, light ester PO (above, manufactured by Kyoeisha Chemical Co., Ltd.), New Frontier PHE, CEA, PHE-2, BR-30, BR-31, BR-31M, BR-32 (above, Daiichi Kogyo) Pharmaceutical Co., Ltd.).

  Examples of unsaturated monomers having two (meth) acryloyl groups in the molecule include alkyl diols such as 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, and 1,9-nonanediol diacrylate. Examples include polyalkylene glycol diacrylates such as diacrylate, ethylene glycol di (meth) acrylate, tetraethylene glycol diacrylate, and tripropylene glycol diacrylate, neopentyl glycol di (meth) acrylate, and tricyclodecane methanol diacrylate.

  As unsaturated monomers having a bisphenol skeleton, ethylene oxide-added bisphenol A (meth) acrylic acid ester, ethylene oxide-added tetrabromobisphenol A (meth) acrylic acid ester, propylene oxide-added bisphenol A (meth) acrylic acid ester, propylene oxide-added Tetrabromobisphenol A (meth) acrylic acid ester, bisphenol A epoxy (meth) acrylate obtained by epoxy ring-opening reaction of bisphenol A diglycidyl ether and (meth) acrylic acid, tetrabromobisphenol A diglycidyl ether and (meth) Tetrabromobisphenol A epoxy (meth) acrylate, bisphenol F diglycidyl ether and (meth) obtained by epoxy ring-opening reaction with acrylic acid Bisphenol F epoxy (meth) acrylate obtained by epoxy ring-opening reaction with crylic acid, tetrabromobisphenol F epoxy (meth) acrylate obtained by epoxy ring-opening reaction of tetrabromobisphenol F diglycidyl ether and (meth) acrylic acid Etc.

  Commercially available unsaturated monomers having such a structure include Biscote # 700 and # 540 (above, manufactured by Osaka Organic Chemical Industry Co., Ltd.), Aronix M-208, M-210 (above, Toagosei Co., Ltd.) ), NK ester BPE-100, BPE-200, BPE-500, A-BPE-4 (above, Shin-Nakamura Chemical Co., Ltd.), light ester BP-4EA, BP-4PA, epoxy ester 3002M, 3002A 3000M, 3000A (above, manufactured by Kyoeisha Chemical Co., Ltd.), KAYARAD R-551, R-712 (above, manufactured by Nippon Kayaku Co., Ltd.), BPE-4, BPE-10, BR-42M (above, No. 1) Manufactured by Ichi Kogyo Seiyaku Co., Ltd.), Lipoxy VR-77, VR-60, VR-90, SP-1506, SP-1506, SP-1507, SP-1509, SP 1563 (manufactured by Showa High Polymer Co., Ltd.), NEOPOL V779, NEOPOL V779MA (manufactured by Japan U-PICA Co., Ltd.), and the like.

  Furthermore, as a trifunctional or higher functional (meth) acrylate unsaturated monomer, a trihydric or higher polyhydric alcohol (meth) acrylate such as trimethylolpropane litho (meth) acrylate, pentaerythritol tri (meth) acrylate or trimethylol. Propane trioxyethyl (meth) acrylate, tris (2-acryloyloxyethyl) isocyanurate, etc. are listed, and commercially available products include Aronix M305, M309, M310, M315, M320, M350, M360, M408 (and above, Toagosei) Made by Co., Ltd., Biscoat # 295, # 300, # 360, GPT, 3PA, # 400 (Osaka Organic Chemical Co., Ltd.), NK ester TMPT, A-TMPT, A-TMM-3, A- TMM-3L, A-TMMT (above, Shinnaka Chemical Co., Ltd.), Light Acrylate TMP-A, TMP-6EO-3A, PE-3A, PE-4A, DPE-6A (above, Kyoeisha Chemical Co., Ltd., KAYARAD PET-30, GPO-303, TMPTA) , TPA-320, DPHA, D-310, DPCA-20, DPCA-60 (manufactured by Nippon Kayaku Co., Ltd.) and the like.

  In addition, a urethane (meth) acrylate oligomer may be blended. Examples of urethane (meth) acrylates include polyether polyols such as polyethylene glycol and polytetramethyl glycol; succinic acid, adipic acid, azelaic acid, sebacic acid, phthalic acid, tetrahydro (anhydrous) phthalic acid, hexahydro (anhydrous) phthalic acid Obtained by reaction of a dibasic acid such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, etc. Polyester polyol, polyε-caprolactone-modified polyol; polymethylvalerolactone-modified polyol; ethylene glycol, propylene glycol, 1,4-butanediol, Alkyl polyols such as 1,6-hexanediol and neopentyl glycol; bisphenol A skeleton alkylene oxide modified polyols such as ethylene oxide-added bisphenol A and propylene oxide-added bisphenol A; bisphenol F skeleton alkylene such as ethylene oxide-added bisphenol F and propylene oxide-added bisphenol F Oxide-modified polyols or mixtures thereof and organic polyisocyanates such as tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, etc. Manufactured from hydroxy group-containing (meth) acrylate And urethane (meth) acrylate oligomers. A urethane (meth) acrylate oligomer is preferable for maintaining the viscosity of the curable composition of the present invention moderately.

  As commercially available monomers of these urethane (meth) acrylates, for example, Aronix M120, M-150, M-156, M-215, M-220, M-225, M-240, M-245, M-270 ( As mentioned above, manufactured by Toagosei Co., Ltd.), AIB, TBA, LA, LTA, STA, Viscoat # 155, IBXA, Viscoat # 158, # 190, # 150, # 320, HEA, HPA, Viscoat # 2000, # 2100, DMA, biscort # 195, # 230, # 260, # 215, # 335HP, # 310HP, # 310HG, # 312 (above, manufactured by Osaka Organic Chemical Industry Co., Ltd.), Light Acrylate IAA, LA, SA , BO-A, EC-A, MTG-A, DMP-A, THF-A, IB-XA, HOA, HOP-A, HOA-M L, HOA-MPE, light acrylate 3EG-A, 4EG-A, 9EG-A, NP-A, 1,6HX-A, DCP-A (manufactured by Kyoeisha Chemical Co., Ltd.), KAYARADTC-110S, HDDA, NPGDA, TPGDA, PEG400DA, MANDA, HX-220, HX-620 (Nippon Kayaku Co., Ltd.), FA-511A, 512A, 513A (Hitachi Chemical Co., Ltd.), VP (BASF) ACMO, DMAA, DMAPAA (manufactured by Kojin Co., Ltd.) and the like.

  The urethane (meth) acrylate oligomer is obtained as a reaction product of (a) hydroxy group-containing (meth) acrylate, (b) organic polyisocyanate and (c) polyol, but (a) hydroxy group-containing (meth). A reaction product obtained by reacting an acrylate with (b) an organic polyisocyanate and then (c) a polyol is preferable.

  The above unsaturated monomers may be used alone, or a plurality of types may be mixed as necessary.

  Examples of photo radical polymerization initiators include acetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole 3-methylacetophenone, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyldimethyl ketal, 1- (4-isopropylphenyl)- 2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethyl Oxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, Examples thereof include bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, ethyl-2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, and the like.

  Commercially available radical photopolymerization initiators include, for example, Irgacure 184, 369, 651, 500, 819, 907, 784, 2959, CGI 1700, CGI 1750, CGI 11850, CG 24-61, Darocurl 116, 1173 (above, Ciba Specialty Chemicals ( Co., Ltd.), Lucirin LR8728, 8893X (manufactured by BASF), Ubekrill P36 (manufactured by UCB), KIP150 (manufactured by Lamberti), and the like. Among these, Lucirin LR8883X is preferable from the viewpoint of being liquid and easily dissolved and having high sensitivity.

  The radical photopolymerization initiator is preferably blended in the total composition in an amount of 0.01 to 10% by weight, particularly 0.5 to 7% by weight. The upper limit of the blending amount is preferably in this range from the viewpoints of the curing characteristics of the composition, the mechanical properties and optical characteristics of the cured product, handling, and the like, and the lower limit of the blending amount is preferably in the range of preventing a decrease in the curing rate.

  The composition of the present invention may further contain a photosensitizer. Examples of the photosensitizer include triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid, 4-dimethyl Examples include methyl aminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate and the like, and examples of commercially available products include Ubekryl P102, 103, 104, 105 (manufactured by UCB). .

  Further, in addition to the above components, various additives as necessary include, for example, antioxidants, ultraviolet absorbers, light stabilizers, silane coupling agents, coating surface improvers, thermal polymerization inhibitors, leveling agents, surfactants. Colorants, storage stabilizers, plasticizers, lubricants, solvents, fillers, anti-aging agents, wettability improvers, mold release agents, and the like can be blended as necessary.

  Here, examples of the antioxidant include Irganox 1010, 1035, 1076, 1222 (manufactured by Ciba Specialty Chemicals Co., Ltd.), Antigen P, 3C, FR, GA-80 (manufactured by Sumitomo Chemical Co., Ltd.). Examples of the ultraviolet absorber include Tinuvin P, 234, 320, 326, 327, 328, 329, 213 (manufactured by Ciba Specialty Chemicals Co., Ltd.), Seesorb 102, 103, 110, 501; 202, 712, 704 (above, manufactured by Sipro Kasei Co., Ltd.) and the like. Examples of the light stabilizer include Tinuvin 292, 144, 622LD (above, manufactured by Ciba Specialty Chemicals Co., Ltd.), Sanol LS770 ( Sankyo Co., Ltd.), Sumisorb TM-0 1 (manufactured by Sumitomo Chemical Co., Ltd.) and the like. Examples of the silane coupling agent include γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, commercially available Examples of the product include SH6062, 6030 (above, manufactured by Toray Dow Corning Silicone Co., Ltd.), KBE903, 603, 403 (above, manufactured by Shin-Etsu Chemical Co., Ltd.) and the like. Examples include silicone additives such as dimethylsiloxane polyether and nonionic fluorosurfactants, and commercially available silicone additives include DC-57, DC-190 (above, manufactured by Dow Corning), SH-28PA, SH-29PA, SH-30PA, SH-190 (above, Toray Dow Corning Silicone Co., Ltd.), KF351, KF352, KF353, KF354 (above, manufactured by Shin-Etsu Chemical Co., Ltd.), L-700, L-7002, L-7500, FK-024-90 (above, Nihon Unicar Co., Ltd.) )), And commercially available non-ionic fluorosurfactants include FC-430, FC-171 (above 3M), Megafac F-176, F-177, R-08, F780 (above Dainippon Ink Co., Ltd.) and the like, and the release agent includes Prisurf A208F (Daiichi Kogyo Seiyaku Co., Ltd.).

  The organic solvent for adjusting the viscosity of the resin liquid of the present invention may be any organic solvent that can be mixed without unevenness such as precipitates, phase separation, and cloudiness when mixed with the resin liquid. For example, acetone, methyl ethyl ketone, Examples thereof include methyl isobutyl ketone, ethanol, propanol, butanol, 2-methoxyethanol, cyclohexanol, cyclohexane, cyclohexanone, toluene, and the like.

  When an organic solvent is added, it is necessary to dry and evaporate the organic solvent during the manufacturing process of the product. However, if a large amount of residual solvent remains in the product, the mechanical properties of crystallization deteriorate. There is also a concern that the organic solvent evaporates and diffuses during use as a product, causing bad odor and adverse health effects. For this reason, organic solvents having a high boiling point are not preferable because the amount of residual solvent increases.

  However, if the boiling point is too low, it will evaporate violently, resulting in rough surface, condensation water adhering to the surface of the composition due to the heat of vaporization during drying, resulting in surface defects and vapor concentration. It becomes higher and the risk of ignition etc. increases.

  Therefore, the boiling point of the organic solvent is preferably 50 ° C. or higher and 150 ° C. or lower, and more preferably 70 ° C. or higher and 120 ° C. or lower. From the viewpoint of the solubility of the material and the boiling point, the organic solvent is preferably methyl ethyl ketone (bp. 79.6 ° C), 1-propanol (bp. 97.2 ° C) or the like.

  The amount of the organic solvent added to the resin solution of the present invention depends on the type of the solvent and the viscosity of the resin solution before the addition of the solvent. , 40% by weight or less, preferably 15% by weight or more and 30% by weight or less. If the amount of the organic solvent added is too small, the effect of reducing the viscosity and the effect of increasing the coating amount are small, and the coating property is not sufficiently improved.

  However, if the resin liquid is diluted too much, the viscosity is too low and the liquid flows on the sheet-like body to cause unevenness, or the liquid turns around the back surface of the sheet-like body. In addition, the drying process may not be sufficient, and a large amount of organic solvent may remain in the product, resulting in deterioration of product function, volatilization during product use, generation of bad odors, and adverse health effects. Occurs.

  The resin liquid of the present invention can be produced by mixing the above-mentioned components by a conventional method, and can be produced by heating and dissolving as necessary. The viscosity of the resin liquid thus prepared is usually 10 to 50000 mPa · s / 25 ° C.

  When the resin liquid is supplied to the sheet W or the embossing roller 13, if the viscosity is too high, it is difficult to supply the composition uniformly. When manufacturing a lens, uneven coating, undulation, and air bubbles are generated. For this reason, it becomes difficult to obtain the target lens thickness, and the lens performance cannot be fully exhibited.

  This tendency is particularly noticeable when the line speed is increased. Accordingly, in this case, the liquid viscosity is preferably low, preferably 10 to 100 mPa · s, and more preferably 10 to 50 mPa · s. Such a low viscosity can be adjusted by adding an appropriate amount of an organic solvent. Further, the viscosity can be adjusted by setting the temperature of the coating solution to be kept warm.

  On the other hand, if the viscosity after evaporation of the solvent is too low, it may be difficult to control the lens thickness when embossing with the embossing roller 13, and a uniform lens with a certain thickness may not be formed. A preferred viscosity is 10 to 3000 mPa · s. When an organic solvent is mixed, by providing a step of evaporating the organic solvent by heat drying or the like between the steps of supplying the resin solution and embossing with the embossing roller 13, the viscosity is low when the resin solution is supplied. Thus, when the embossing roller 13 is used for embossing, the organic solvent is dried and the embossing roller 13 can be uniformly embossed with a resin solution having a higher viscosity.

  In the case of a prism lens sheet, the cured product obtained by curing the resin liquid of the present invention with radiation particularly preferably has the following physical properties (refractive index, softening point).

  The refractive index is preferably 1.55 or more and more preferably 1.56 or more at 25 ° C. of the cured product. This is because when the refractive index at 25 ° C. of the cured product is less than 1.55, when a prism lens sheet is formed using this composition, sufficient front luminance may not be ensured.

  As a softening point, 40 degreeC or more is preferable and 50 degreeC or more is more preferable. This is because if the softening point is less than 40 ° C., the heat resistance may not be sufficient.

  Next, returning to FIG. 1, the operation of the embossed sheet manufacturing apparatus 10 will be described. The sheet W is sent out from the sheet supply unit 11 at a constant speed. The sheet W is wound around the first suction drum 24, is sucked and held, and continuously travels. Next, the sheet W is sent to the dust remover 28, and dust attached to the surface of the sheet W is removed.

  Next, the sheet W is fed into the coating unit 12 and the resin liquid is applied to the surface of the sheet W. After the application, the resin liquid applied to the sheet W is dried by the drying means 19 and the solvent is evaporated. Thus, before the sheet W is wound around the embossing roller 13 and cured, a step of drying the solvent contained in the coating layer is provided, so that the function of the product due to the added solvent remaining after curing is provided. There is no worry about deterioration or strength deterioration of the cured film. Similarly, there is no concern that the solvent will be released during use of the product, resulting in malodors or adverse health effects.

  Next, the sheet W is fed into a forming unit composed of an embossing roller 13 and a nip roller 14. As a result, roller forming is performed while pressing the continuously running sheet W with the rotating embossing roller 13 and the nip roller 14 at the 3 o'clock position of the embossing roller 13. That is, the sheet W is wound around the rotating embossing roller 13, and the unevenness on the surface of the embossing roller 13 is transferred to the resin layer.

  Next, in a state where the sheet W is wound around the embossing roller 13, the resin curing unit 15 transmits the sheet W and irradiates the resin liquid layer with radiation, thereby curing the resin liquid layer. Thereafter, the sheet W is peeled off from the embossing roller 13 by winding the sheet W around the peeling roller 16 at the 9 o'clock position of the embossing roller 13.

  In addition, although not shown in FIG. 1, in order to further accelerate hardening after peeling the sheet | seat W, radiation irradiation can also be performed again.

  The peeled sheet W is conveyed to the defect inspection means 21 and the defect of the concavo-convex pattern transferred and formed on the sheet W is inspected. By such defect inspection means 21, it is possible to inspect defects in the concavo-convex pattern transferred and formed on the sheet W, and it becomes easy to eliminate defective portions.

  The sheet W is supported by a plurality of guide rollers G, G... Between the coating unit 12 and the defect inspection unit 21, and the surface of the sheet W is in contact with the embossing roller 13 through a resin layer. Only.

  Then, the second guide roller G1 downstream of the defect inspection means 21 comes into contact with the surface of the sheet W for the first time. Therefore, the state in which the reaction rate of the resin liquid layer is 70% or more is required.

  That is, if the resin reaction rate is 70% or more, there is no problem even if the uneven pattern on the surface of the sheet W is brought into contact with the guide roller G1. The reason for this is that if the concavo-convex pattern surface comes into contact with the guide roller G1, the concavo-convex shape is likely to be crushed due to the contact pressure. This is because it becomes difficult to deform.

  Therefore, according to the present invention, a concavo-convex sheet having a regular fine concavo-convex pattern formed on the surface can be manufactured with high quality without defects and with high line speed and high productivity.

  The reaction rate of the resin that does not cause a problem when the fine uneven pattern surface comes into contact with the guide roller G1 is more preferably 75% or more, and further preferably 80% or more.

  Further, it is not a method of managing by the reaction rate of the resin liquid layer when the guide roller G1 and the surface of the sheet W are in contact with each other, but in a predetermined time from when the sheet W is peeled off from the embossing roller 13 until it comes into contact with the guide roller G1. In the case of the management method, the predetermined time is preferably 10 seconds or more, more preferably 15 seconds or more, and further preferably 20 seconds or more. Thus, when the predetermined time elapses, curing (reaction) proceeds and the uneven pattern is difficult to deform.

  In addition, the reaction rate of the cured resin (the residual rate of the reactive group was measured by FT-IR (Fourier transform infrared spectrophotometer)) when released from the ultraviolet ray may increase with time. It has been confirmed.

  Actually, the reaction rate after UV irradiation and release of the cured resin varies depending on the type of the resin, but the reaction often stops in 10 to 20 seconds. Moreover, in the resin of the Example mentioned later, the liquid which diluted the ultraviolet curable resin with the solvent was apply | coated initially, and the cured resin contains the solvent after ultraviolet irradiation and mold release. After the mold release, the solvent is dried before being wound up (or the protective sheet is laminated). Of course, although the amount of residual solvent does not become zero, it is not preferable to wind up without releasing time after mold release in order to dry the solvent as much as possible.

  Although not shown in FIG. 1, as described above, when the temperature / humidity control means is provided between the peeling roller 16 and the defect inspection means 21, or immediately after the defect inspection means 21 (downstream), The temperature is managed at 23 ± 1 ° C., for example, and the humidity is managed at 40 ± 2% RH, for example.

  Since the transferred pattern is dried and absorbed by temperature and humidity, the pattern is slightly deformed. Although it is difficult to suppress this, if the product is managed in a certain environment as described above, it can be managed to have the same amount of deformation, so that the product can be maintained at a constant quality.

  Next, the sheet W is conveyed to the dancer roller 30 downstream of the guide roller G1, and the tension of the sheet W is controlled by the lifting and lowering operation of the moving roller 30C provided between the fixed rollers 30A and 30B. Since the dancer roller 30 (tension control means) controls the tension of the sheet W, the traveling speed of the sheet W is stabilized and the transfer shape is improved.

  Next, the sheet W is wound around the second suction drum 26, sucked and held, and continuously travels.

  Next, the protective film H supplied from the protective film supply means 17 is supplied to the surface of the sheet W, and is sandwiched between the pair of fixed rollers 32A and the nip rollers 32E of the edge position control means 32 in a state where the two films are overlapped. The position in the width direction of the sheet W is controlled. The concavo-convex sheet of the present invention forms a fine pattern on the sheet surface, so if there is a deviation or fluctuation during sheet conveyance, it leads to the occurrence of defects very sensitively. If the position can be controlled, the above-described defect can be effectively prevented.

  Next, the sheet W is conveyed to the sheet winding unit 18, and is wound and stored by the winding roll of the sheet winding unit 18 in a state where the protective film H overlaps the surface of the sheet W. A schematic cross-sectional shape of such a sheet W after completion is shown in FIG. On the surface of the sheet W, a resin layer F to which the unevenness on the surface of the embossing roller 13 is transferred is formed.

  The completed sheet W wound up and stored by the winding roll can be cut off to a product size offline after a series of steps. Such a completed sheet W is preferably used as an optical film.

  According to the present embodiment described above, the unevenness is transferred to the radiation curable resin layer, and after being irradiated with radiation in that state, it is peeled off from the embossing roller 13, and the reaction rate of the resin liquid layer is 70% or more. Since the concave / convex pattern on the surface of the sheet W is brought into contact with the roller member or the support member, a concave / convex sheet having a regular fine concave / convex pattern formed on the surface is manufactured with high quality and high productivity without defects. can do.

  As mentioned above, although the example of embodiment of the manufacturing method of the uneven | corrugated sheet | seat which concerns on this invention was demonstrated, this invention is not limited to the example of the said embodiment, Various aspects can be taken.

  For example, in the example of the present embodiment, an aspect using the roller-shaped embossing roller 13 is adopted, but an aspect using an uneven pattern (embossed shape) formed on the surface of a belt-like body such as an endless belt may also be used. Can be adopted. This is because even such a belt-like body acts in the same manner as a cylindrical roller, and the same effect can be obtained.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[Adjustment of resin liquid]
The compounds shown in the table of FIG. 4 were mixed at the stated weight ratio, heated to 50 ° C. and dissolved by stirring to obtain a resin liquid. In addition, the name and content of each compound are as follows.

EB3700: Everkrill 3700, manufactured by Daicel UC Corporation,
Bisphenol A type epoxy acrylate,
(Viscosity: 2200 mPa · s / 65 ° C)
BPE200: NK ester BPE-200, manufactured by Shin-Nakamura Chemical Co., Ltd.
Ethylene oxide-added bisphenol A methacrylate,
(Viscosity: 590 mPa · s / 25 ° C)
BR-31: New Frontier BR-31, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.
Tribromophenoxyethyl acrylate,
(Solid at normal temperature, melting point 50 ° C or higher)
LR8883X: Lucirin LR8883X, a photo radical generator manufactured by BASF Corporation,
Ethyl-2,4,6-trimethylbenzoylethoxyphenyl osphine oxide MEK: methyl ethyl ketone [production of embossed sheet]
The embossed sheet was manufactured using the embossed sheet manufacturing apparatus 10 having the configuration shown in FIG.

  As the sheet W, a transparent PET (polyethylene terephthalate) film having a width of 500 mm and a thickness of 100 μm was used.

  As the embossing roller 13, a roller made of S45C having a length (width direction of the sheet W) of 700 mm and a diameter of 300 mm and having a surface material of nickel was used. Grooves with a pitch of 50 μm in the roller axial direction were formed on the entire circumference of the surface of the roller by cutting using a diamond tool (single point). The cross-sectional shape of the groove is a triangular shape with an apex angle of 90 degrees, and the bottom of the groove is a triangular shape with a 90 degree without a flat portion. That is, the groove width is 50 μm and the groove depth is about 25 μm.

  Since the groove is endless without a seam in the circumferential direction of the roller, the embossing roller 13 can form a lenticular lens (prism sheet) having a triangular cross section on the sheet W. The surface of the roller was plated with nickel after the grooves were processed. A schematic cross-sectional view of the embossing roller 13 is as shown in FIG.

  The thickness of the coating solution F (resin solution) in the wet state is such that the supply amount of the coating solution F to the coating head 12C is a liquid supply device (liquid feed pump) 12B so that the film thickness after drying the organic solvent is 20 μm. Controlled by

  As the drying means 19, a hot air circulation type apparatus was used. The temperature of the hot air was set to 100 ° C.

  As the nip roller 14, a roller having a diameter of 200 mm and a silicon rubber layer having a rubber hardness of 90 formed on the surface thereof was used. The nip pressure (effective nip pressure) for pressing the sheet W by the embossing roller 13 and the nip roller 14 was 0.5 Pa.

A metal halide lamp was used as the resin curing means 15 and irradiation was performed with an energy of 1000 mJ / cm ² .

  As described above, when the sheet was operated at a line speed of 2 m / min, a sheet W on which an uneven pattern corresponding to the examples and comparative examples shown in the table of FIG. 5 was formed was obtained.

[Measurement of resin reaction rate]
The reaction rate (residual rate of the reactive group) of the resin when the uneven pattern on the surface of the sheet W was in contact with the guide roller G1 was measured by FT-IR (Fourier transform infrared spectrophotometer).

[Temperature and humidity control conditions]
The temperature and humidity control conditions until the sheet W comes off from the embossing roller 13 and comes into contact with the guide roller G1 were controlled as follows.

  Note 1: Temperature was controlled at 23 ± 1 ° C. and humidity was controlled at 40 ± 2% RH.

  Note 2: Temperature and humidity were not controlled. The temperature at this time fluctuated in the range of 22 to 30 ° C., and the humidity fluctuated in the range of 30 to 45% RH.

[Embossed shape evaluation]
The sheet W was cut, and the embossed shape was evaluated by measuring the cross-sectional shape at a plurality of locations of the concavo-convex pattern using an SEM (scanning electron microscope), and ranked as follows.

○: The shape of the surface of the embossing roller is almost reproduced. Δ: Some deformation (within 1 μm) is recognized. X: A considerable deformation (1 μm or more) is recognized. According to the table of FIG. In 1 and 2, the uneven pattern on the surface of the sheet W was brought into contact with the guide roller G1 while the reaction rate of the resin liquid layer was 70% or more, and the temperature and humidity were controlled. It is reproduced.

  On the other hand, in Comparative Examples 1 to 3, the uneven pattern on the surface of the sheet W is brought into contact with the guide roller G1 in a state where the reaction rate of the resin liquid layer is less than 70%. Was NG.

  The effects of the present invention were confirmed from the following results.

The figure which shows the structure of the manufacturing apparatus of the embossed sheet | seat with which this invention is applied. Sectional view showing the outline of the embossing roller Sectional view showing the outline of the embossed sheet Table showing resin liquid formulation Table showing conditions and results of Examples and Comparative Examples The conceptual diagram which shows the structure of the manufacturing apparatus of the embossed sheet of a prior art example The conceptual diagram which shows the other structure of the manufacturing apparatus of the embossed sheet | seat of a prior art example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Embossed sheet manufacturing apparatus, 11 ... Sheet supply means, 12 ... Application means, 13 ... Emboss roller, 14 ... Nip roller, 15 ... Resin curing means, 16 ... Peeling roller, 17 ... Protective film supply means, 18 ... Sheet winding Removal means, 21 ... Defect inspection means, 24 ... First suction drum, 26 ... Second suction drum, 28 ... Dust remover, 30 ... Dancer roller, 32 ... Edge position control means, H ... Protective film, W ... Sheet

Claims (8)

In the method for producing a concavo-convex sheet by transferring the concavo-convex on the surface of the concavo-convex roller to the surface of the sheet-like body,
By applying the radiation curable resin liquid, the belt-like flexible sheet-like body on which the resin liquid layer is formed is continuously run,
The sheet-like body is wound around the rotating uneven roller, and the unevenness on the uneven roller surface is transferred to the resin liquid layer,
Irradiating the resin liquid layer with radiation in a state where the sheet-like body is wound around the uneven roller,
The sheet-like body is peeled from the uneven roller,
A method for producing a concavo-convex sheet, wherein the concavo-convex pattern on the surface of the sheet-like body is brought into contact with a roller member or a support member in a state where the reaction rate of the resin liquid layer is 70% or more. In the method for producing a concavo-convex sheet by transferring the concavo-convex on the surface of the concavo-convex roller to the surface of the sheet-like body,
By applying the radiation curable resin liquid, the belt-like flexible sheet-like body on which the resin liquid layer is formed is continuously run,
The sheet-like body is wound around the rotating uneven roller, and the unevenness on the uneven roller surface is transferred to the resin liquid layer,
Irradiating the resin liquid layer with radiation in a state where the sheet-like body is wound around the uneven roller,
A method for producing a concavo-convex sheet, wherein the concavo-convex pattern on the surface of the sheet-like body is brought into contact with a roller member or a support member after 10 seconds or more have passed after the sheet-like body is peeled from the concavo-convex roller.   After the sheet-like body is peeled off from the uneven roller, the sheet-like body is placed in a space controlled to a predetermined temperature and humidity until the uneven pattern on the surface of the sheet-like body is brought into contact with a roller member or a support member. The manufacturing method of the uneven | corrugated sheet | seat of Claim 1 or 2 characterized by the above-mentioned.   After the sheet-like body is peeled from the uneven roller, the surface of the sheet-like body is irradiated with radiation until the uneven pattern on the surface of the sheet-like body is brought into contact with a roller member or a support member, or the sheet The method for producing a concavo-convex sheet according to any one of claims 1 to 3, wherein the shaped body is heated.   The method for producing a concavo-convex sheet according to any one of claims 1 to 4, wherein the radiation curable resin is an ultraviolet curable resin, and the radiation is an ultraviolet ray.   6. After making the uneven | corrugated pattern of the said sheet-like body surface contact with a roller member or a supporting member, a protective sheet is laminated on the surface of the said sheet-like body, and it winds up in roll shape, The manufacturing method of the uneven | corrugated sheet | seat of 1 item | term.   The method for manufacturing a concavo-convex sheet according to any one of claims 1 to 6, wherein a pitch of the concavo-convex pattern transferred and formed on the sheet-like body is 100 µm or less.   The method for producing a concavo-convex sheet according to any one of claims 1 to 7, wherein the concavo-convex sheet is used as an optical film.

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