JP2007248849A - Radiation curable composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a rugged sheet, in which a regular fine rugged pattern is formed on its surface, with high quality without any defect at a high line speed and also at high productivity. <P>SOLUTION: The radiation-curable composition is used for the method of manufacturing the rugged pattern sheet by making a rugged pattern die in press contact with a sheet W, in which the liquid radiation-curable composition is applied on its surface, and transferring the rugged pattern of the rugged pattern die to the surface of the sheet. The radiation-curable composition contains an acrylate or methacrylate having a predetermined structure and a photopolymerization initiator. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a radiation curable composition, and in particular, a radiation curable composition suitable for producing a sheet-like material such as an embossed sheet having an antireflection effect in which a regular fine uneven pattern is formed on the surface. Related to things.

  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 8).

  For example, in an apparatus having a configuration as shown in FIG. 5, 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. 6, 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, and is cured by irradiating the resin with ionizing radiation, 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).

  Moreover, the thing of various compositions is also disclosed as a composition used for manufacture of such a sheet-like material (refer patent documents 5-8). For example, Patent Document 5 defines the viscosity and surface tension of a radiation curable composition. Patent Document 6 discloses a halogen-containing (meth) acrylate as a monomer and is said to be able to cope with a higher refractive index.

Patent Document 7 discloses methyl styrene as a composition, and it is said that the viscosity of the composition can be lowered to impart processing and coating suitability. In Patent Document 8, (meth) acrylate containing a fluorene skeleton is used as a radiation curable composition and mixed with another monomer having an ethylenically unsaturated bond for dilution.
Japanese Patent No. 2533379 Japanese Patent No. 2891344 JP-A-11-300768 JP 2000-141481 A JP 2001-314815 A JP 2004-51941 A JP-T-2001-526715 Japanese Patent No. 3130555

  Incidentally, in recent years, it has been desired to increase the refractive index of optical resin layers for reasons of optical design. For example, in the case of a Fresnel lens, as the refractive index of the optical resin layer is increased, the lens pattern can be made shallower, release from the mold becomes easier, and productivity can be improved.

  Also, for example, in the case of a prism sheet for improving the front brightness of a backlight unit used in a liquid crystal display device or the like, when the apex angle of the prism is designed to be the same, the front brightness increases as the refractive index of the optical resin layer increases. Can be improved.

  On the other hand, in order to achieve such a high refractive index of the optical resin layer, it is necessary to use a compound containing a large amount of an aromatic ring structure or a halogen compound such as bromine as the curable composition. However, in general, such compounds are highly viscous liquids or solids. Accordingly, since the resin liquid also has a high viscosity, when manufactured by the method as described above, there is a problem that the applicability is further deteriorated, it is difficult to increase the line speed, and it is difficult to improve the productivity. .

  However, the conventional technology has not sufficiently dealt with the above problems at present. For example, the aforementioned Patent Document 5 defines the viscosity and surface tension of the radiation curable composition in order to improve the flow of the resin into the mold and increase the productivity. This is different from the method in which resin is applied. Moreover, the specific composition of resin (compound) and the specific method of making resin low viscosity are not disclosed.

  In Patent Document 6 described above, halogen-containing (meth) acrylates and the like are described as high refractive index monomers, but the viscosity of the radiation curable composition is several hundred mPa · s to several thousand Pa · s. It is considered that s is preferable, and no consideration is given to reducing the viscosity for improving the coating speed.

  In the aforementioned Patent Document 7, methylstyrene is described as a compound having a relatively high refractive index capable of lowering the viscosity of the radiation curable composition and imparting processing and coating suitability. Since the compound remains, if the amount used is too large, the refractive index will decrease and the physical properties of the cured film will deteriorate. In order to avoid this, the viscosity can only be lowered to about several hundred mPa · s, and the effect of increasing the coating speed is insufficient.

  Patent Document 8 already described describes that (meth) acrylate containing a fluorene skeleton is used as a radiation curable composition and is mixed with another monomer having an ethylenically unsaturated bond for dilution. However, since this monomer is cured and remains in the cured film, if the amount used is too large, the physical properties of the cured film are deteriorated. In order to avoid this, the viscosity can only be lowered to several tens to hundreds of mPa · s, and the effect of increasing the coating speed is insufficient. In Patent Document 8, there is no problem of continuously creating a fine structure on a sheet with high productivity.

  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 radiation curable composition suitable for producing a concavo-convex sheet suitable for the above, more specifically, a radiation curable composition having a low viscosity, good coatability and a high refractive index. To do.

In order to achieve the above-mentioned object, the present invention has a concavo-convex shape adhered to a sheet-like body having a liquid radiation-curable composition applied to the surface, and the concavo-convex shape of the concavo-convex surface is applied to the surface of the sheet-like body. The radiation curable composition used in the method for producing a concavo-convex sheet to be transferred and comprising the following (A), (B), (C) and (D): A composition is provided.
(A) Compound having a structure represented by the following chemical formula 1

ただし、Ｒ１は、Ｈ又はＣＨ３であり、ｍ及びｎは、１又は２である。
（Ｂ）１以上の芳香環をもつアクリレート又はメタアクリレート化合物
（Ｃ）前記（Ａ）及び（Ｂ）以外の分子内に１以上の重合性エチレン性不飽和結合をもつ化合物
（Ｄ）光重合開始剤
本発明において、前記（Ｂ）が、下記の化学式２、化学式３及び化学式４のうちの１以上からなる化合物であることが好ましい。なお、化合物（Ｂ）として、同じ式で異なる化合物が同時に含まれていてもよい。

However, R1 is H or CH3, and m and n are 1 or 2.
(B) An acrylate or methacrylate compound having one or more aromatic rings (C) A compound having one or more polymerizable ethylenically unsaturated bonds in the molecule other than the above (A) and (B) (D) Initiating photopolymerization Agent In the present invention, the (B) is preferably a compound comprising one or more of the following chemical formula 2, chemical formula 3 and chemical formula 4. In addition, as a compound (B), the different compound by the same formula may be contained simultaneously.

ただし、Ｒ１は、Ｈ又はＣＨ３であり、Ｘ_１は、Ｃｌ又はＢｒである。ｐは、１〜３の整数である。

However, R1 is H or CH3, _{X 1} is Cl or Br. p is an integer of 1 to 3.

ただし、Ｒ１は、Ｈ又はＣＨ３であり、Ｘ_１は、Ｃｌ又はＢｒである。ｑは、１〜３の整数である。

However, R1 is H or CH3, _{X 1} is Cl or Br. q is an integer of 1 to 3.

ただし、Ｒ１は、Ｈ又はＣＨ３であり、Ｘ_２は、Ｃｌ又はＢｒである。ｒは、０〜２の整数であり、ｓは、０〜３の整数である。Ｒ２は、Ｈ、ＣＨ３、Ｃ１〜Ｃ８のアルキル基、Ｐｈ又は−Ｃ（ＣＨ３）−Ｐｈである。
（Ｃ）前記（Ａ）及び（Ｂ）以外の分子内に１以上の重合性エチレン性不飽和結合をもつ化合物
（Ｄ）光重合開始剤
また、本発明において、前記（Ｄ）が、２，４，６−トリメチルベンゾイルエトキシフェニルフォスフィンオキシド、２，４，６−トリメチルベンゾイルジフェニルフォスフィンオキシド、又はビス−（２，６−ジメトキシベンゾイル）−２，４，４−トリメチルペンチルフォスフィンオキシドであることが好ましい。

However, R1 is H or CH3, _{X 2} is Cl or Br. r is an integer of 0 to 2, and s is an integer of 0 to 3. R2 is H, CH3, a C1-C8 alkyl group, Ph or -C (CH3) -Ph.
(C) Compound (D) photopolymerization initiator having one or more polymerizable ethylenically unsaturated bonds in the molecule other than (A) and (B) In the present invention, (D) is 2, 4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, or bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide It is preferable.

  Moreover, in this invention, it is preferable that the refractive index of the said radiation-curable composition after transfer formation is 1.58 or more.

  Moreover, in this invention, it is preferable that the said radiation-curable composition at the time of application | coating contains 10 weight% or more of organic solvents. Moreover, in this invention, it is preferable that the viscosity of the said radiation-curable composition at the time of application | coating is 100 mPa * s or less. When the composition contains such an amount of the organic solvent and has such a low viscosity, a layer of the composition can be uniformly formed on the sheet-like body without surface defects such as coating stripes and foam failure.

  According to the present invention, a cured film is made to have a high refractive index by using (meth) acrylate containing a fluorene skeleton, and further, by using a radiation curable composition that has been diluted with a solvent to reduce the viscosity, a high line speed is achieved. -Can be manufactured with good productivity. The used organic solvent is heat-dried after application to curing, but high sensitivity can be maintained even after heat-drying by using a specific initiator that has high sensitivity and is difficult to volatilize, and has good productivity.

  In particular, by using a (meth) acrylate containing a fluorene skeleton or a halogen-substituted aromatic ring-containing (meth) acrylate as a radiation curable composition, a fine structure having a high refractive index effective for an optical material or the like can be created. .

As described above, according to the present invention, radiation suitable for producing a concavo-convex sheet having a regular fine concavo-convex pattern formed on the surface thereof with high quality without defects and high productivity with high line speed. A curable composition is obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a conceptual diagram showing a configuration of an embossed sheet manufacturing apparatus 10 to which the radiation curable composition of 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 a concavo-convex roller, a nip roller 14, a resin curing unit 15, and a peeling roller 16. , The protective film supply means 17, the sheet winding means 18, and the like.

  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.

  The coating means 12 is a device that applies a radiation curable resin liquid to the surface of the sheet W, and includes a liquid supply source 12A that supplies the radiation curable resin liquid, a liquid supply device (liquid feed pump) 12B, a coating head 12C, It comprises a support roller 12D that wraps and supports the sheet W at the time of application, a pipe for supplying a radiation curable resin liquid from the liquid supply source 12A to the application head 12C, and the like. 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 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.

  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 counterclockwise (CCW) as shown 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 in the clockwise direction (CW) as shown 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.

  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 in the clockwise direction (CW) as shown 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, a plurality of backup rollers are provided to face each other between the pressing location (9 o'clock position) of the embossing roller 13 and the peeling location (3 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.

  The sheet winding means 18 stores the peeled sheet W, and includes a winding roll that winds the sheet W or the like. In this sheet winding means 18, the protective film H supplied from the adjacent protective film supply means 17 is supplied to the surface of the sheet W, and is stored in the sheet winding means 18 in a state where both films overlap. The

  In the embossed sheet manufacturing apparatus 10, a guide roller or the like that forms a conveyance path of the sheet W may be provided between the coating unit 12 and the embossing roller 13, between the peeling roller 16 and the sheet winding unit 18, and the like. In addition, a tension roller or the like can be provided as needed to absorb slack during conveyance of the sheet W.

  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.

  Among such (meth) acryloyl group-containing compounds, those having a fluorene structure are preferable from the viewpoint of particularly high refractive index, and fluorene-based (meth) acryloyl group-containing compounds having a bisphenoxy group are particularly preferable. Examples of such compounds include bisphenoxyethanol full orange (meth) acrylate and bisphenoxyoxyethylene full orange (meth) acrylate, and commercially available products such as BPEF-A (Osaka Gas Co., Ltd.). and so on.

  Of the (meth) acryloyl group-containing compounds, compounds having a bisphenol skeleton having two aromatic rings are preferred from the viewpoint of particularly high refractive index. Examples of such compounds include epoxy ring-opening reaction of ethylene oxide-added bisphenol A (meth) acrylic acid ester, propylene oxide-added bisphenol A (meth) acrylic acid ester, bisphenol A diglycidyl ether and (meth) acrylic acid. Examples thereof include bisphenol A epoxy (meth) acrylate obtained and bisphenol F epoxy (meth) acrylate obtained by an epoxy ring-opening reaction of bisphenol F diglycidyl ether and (meth) acrylic acid.

  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 (above, Daiichi Kogyo Seiyaku ( Product), 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.

  Further, in addition to the above bisphenol skeleton, it is preferable to use a compound in which Cl and Br halogen groups are substituted on the aromatic ring in order to increase the refractive index. Examples of unsaturated monomers having such a structure include ethylene oxide-added tetrabromobisphenol A (meth) acrylate, propylene oxide-added tetrabromobisphenol A (meth) acrylate, tetrabromobisphenol A diglycidyl ether and (meta ) Tetrabromobisphenol A epoxy (meth) acrylate obtained by epoxy ring-opening reaction with acrylic acid, tetrabromobisphenol F epoxy obtained by epoxy ring-opening reaction between tetrabromobisphenol F diglycidyl ether and (meth) acrylic acid ( And (meth) acrylate.

  BR-42M (Daiichi Kogyo Seiyaku Co., Ltd.), RDX51027 (UCB Radcure Co., Ltd.), etc. are mentioned.

  From the viewpoint of high refraction, an unsaturated monomer having one bromo-substituted aromatic ring is also used. Examples of such compounds include 2-bromophenoxyethyl (meth) acrylate, 4-bromophenoxyethyl (meth) acrylate, 2,4-dibromophenoxyethyl (meth) acrylate, 2,6-dibromophenoxyethyl (meth) ) Acrylate, 2,4,6-tribromophenyl (meth) acrylate, 2,4,6-tribromophenoxyethyl (meth) acrylate, and the like.

  In particular, 3,4,6-tribromophenyl (meth) acrylate and 2,4,6-tribromophenoxyethyl (meth) acrylate substituted with 3 bromo are preferable because of high refractive index.

  Examples of commercially available unsaturated monomers having such a structure include BR-30, BR-31, BR-31M, BR-32 (above, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and the like. It is done.

  In addition, although the refractive index is inferior to that of the above compound, a monofunctional unsaturated monomer having an aromatic ring is used as an unsaturated monomer that has a reasonably high refractive index and lower viscosity and is effective for coating properties. Examples of such unsaturated monomers include phenoxyethyl (meth) acrylate, phenoxy-2-methylethyl (meth) acrylate, phenoxyethoxyethyl (meth) acrylate, and 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, etc. are mentioned.

  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, Light Ester PO (above, Kyoeisha Chemical Co., Ltd.), New Frontier PHE, CEA, PHE-2 (above, Daiichi Kogyo Seiyaku Co., Ltd.) and the like can be mentioned.

  Furthermore, in the present invention, unsaturated monomers other than those described above can be used as necessary for modification of viscosity adjustment, physical properties of the cured film, adhesion to the support, and the like.

  For example, it is possible to use a monofunctional monomer containing only one (meth) acryloyl group-containing compound in order to reduce liquid viscosity or improve brittleness of a cured film. Examples of such monofunctional monomers include isobornyl (meth) acrylate, bornyl (meth) acrylate, tricyclodecanyl (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, isopropyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) acrylate, Butyl (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, Triethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, methoxy ethylene glycol (meth) acrylate, ethoxyethyl (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, methoxy polypropylene glycol (meth) acrylate.

  Further, an unsaturated monomer having two (meth) acryloyl groups in the molecule can be used for adjusting the cured film strength and viscosity. Such unsaturated monomers include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, alkyl diol diacrylates such as 1,9-nonanediol diacrylate, ethylene glycol di (meth) acrylate, Examples include polyalkylene glycol diacrylates such as tetraethylene glycol diacrylate and tripropylene glycol diacrylate, neopentyl glycol di (meth) acrylate, and tricyclodecane methanol diacrylate.

  Furthermore, it is possible to use a trifunctional or higher functional (meth) acrylate unsaturated monomer to increase the strength of the cured film. Examples of such unsaturated monomers include (meth) acrylates of trihydric or higher polyhydric alcohols, such as trimethylolpropane litho (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane trioxyethyl (meth). Acrylate, tris (2-acryloyloxyethyl) isocyanurate, and the like, and commercially available products are Aronix M305, M309, M310, M315, M320, M350, M360, M408 (above, manufactured by Toagosei 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, Shin-Nakamura Chemical Co., Ltd.), Light Ak Rate TMP-A, TMP-6EO-3A, PE-3A, PE-4A, DPE-6A (above, manufactured by Kyoeisha Chemical Co., Ltd., KAYARAD PET-30, GPO-303, TMPTA, TPA-320, DPHA, D -310, DPCA-20, DPCA-60 (Nippon Kayaku Co., Ltd. product) etc. are mentioned.

  In addition, in order to obtain a tough film quality, 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.

  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 them 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. Among these, as the radical photopolymerization initiator used in the present invention, those having a high boiling point or low elevating property and being difficult to evaporate or evaporate during heating drying, reduced pressure drying and the like are preferable.

  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. Of these, Lucirin LR8883X is preferred from the viewpoint of being liquid and easily dissolved, having high sensitivity, and having a high boiling point and being difficult to evaporate during drying.

  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 1.58 or more, more preferably 1.60 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 1.58, 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.

  A radiation curable composition is used as the resin liquid used in the embossed sheet manufacturing apparatus 10, and the radiation curable composition includes the following (A), (B), (C), and (D).

  (A) Compound having a structure represented by the following chemical formula 1

ただし、Ｒ１は、Ｈ又はＣＨ_３であり、ｍ及びｎは、１又は２である。

However, R1 is H or CH _3, m and n is 1 or 2.

(B) An acrylate or methacrylate compound having one or more aromatic rings (C) A compound having one or more polymerizable ethylenically unsaturated bonds in the molecule other than (A) and (B) (D) Photopolymerization initiation Agent According to this resin liquid, the film of the radiation-curable composition after curing can be increased in refractive index by using (meth) acrylate containing a fluorene skeleton. Accordingly, a radiation curable composition having good coating properties and a high refractive index can be obtained.

  Moreover, it is preferable that the (B) is a compound composed of one or more of the following chemical formula 2, chemical formula 3, and chemical formula 4. In addition, as a compound (B), the different compound by the same formula may be contained simultaneously.

ただし、Ｒ１は、Ｈ又はＣＨ_３であり、Ｘ_１は、Ｃｌ又はＢｒである。ｐは、１〜３の整数である。

However, R1 is H or CH _{3, X 1} is Cl or Br. p is an integer of 1 to 3.

ただし、Ｒ１は、Ｈ又はＣＨ_３であり、Ｘ_１は、Ｃｌ又はＢｒである。ｑは、１〜３の整数である。

However, R1 is H or CH _{3, X 1} is Cl or Br. q is an integer of 1 to 3.

ただし、Ｒ１は、Ｈ又はＣＨ_３であり、Ｘ_２は、Ｃｌ又はＢｒである。ｒは、０〜２の整数であり、ｓは、０〜３の整数である。Ｒ２は、Ｈ、ＣＨ_３、Ｃ_１〜Ｃ_８のアルキル基、Ｐｈ又は−Ｃ（ＣＨ_３）−Ｐｈである。

However, R1 is H or CH _{3, X 2} is Cl or Br. r is an integer of 0 to 2, and s is an integer of 0 to 3. R2 _{is, H,} CH _3, alkyl group of C 1 ~C _8, Ph or -C _(CH 3) is -Ph.

(C) Compound having one or more polymerizable ethylenically unsaturated bonds in the molecule other than (A) and (B) (D) Photopolymerization initiator In addition, (D) is 2, 4, 6- Trimethylbenzoylethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, or bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide is preferable.

  In the embossed sheet manufacturing apparatus 10, the sheet W is sent out from the sheet-like body supply unit 11 at a constant speed. The sheet W is fed into the application 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. 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 the continuously running sheet W is pressed by the rotating embossing roller 13 and the nip roller 14 at the 9 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 3 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 sheet take-up means 18 and the protective film H supplied from the protective film supply means 17 is supplied to the surface of the sheet W. It is wound up and stored by a winding roll. FIG. 4 is a cross-sectional view showing an outline of the sheet W (embossed sheet).

  In this way, the resin layer is formed on the surface of the sheet W without unevenness, and further, the embossing by the embossing roller 13 is made stable and uniform. Thereby, the uneven | corrugated sheet | seat in which the regular fine uneven | corrugated pattern was formed in the surface can be manufactured with high quality without a defect.

  As mentioned above, although the example of embodiment of the manufacturing method and apparatus 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.

  Further, in the example of the present embodiment, continuous molding using a roller is illustrated, but press molding using a stamper (concave / convex mold) may be employed instead. In this case, for example, a sheet-like body coated with a radiation curable composition is brought into close contact with a plate-like stamper (concave / convex mold), and a transparent plate (for example, tempered glass) is brought into intimate contact with the back surface of the sheet-like body. While irradiating with radiation. Even if it is such an aspect, it acts similarly to this embodiment and the same effect is acquired.

  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. 2 were mixed at the stated weight ratio, heated to 50 ° C. and dissolved with stirring to obtain 8 types of resin liquids (Examples 1 to 5 and Comparative Examples 1 to 3). In addition, the name and content of each compound are as follows.
BPEF-A: compound of formula (1). R1 = H, m, n = 1, manufactured by Osaka Gas Co., Ltd.
E3000M: Epoxy ester 3000M, manufactured by Kyoeisha Chemical Co., Ltd., bisphenol A diglycidyl ether methacrylic acid adduct (viscosity: 100,000 mPa · s / 25 ° C)
RDX51027: manufactured by UCB-Radcure, tetrabromobisphenol A skeleton-containing epoxy acrylate BPE200: NK ester BPE-200, manufactured by Shin-Nakamura Chemical Co., Ltd., ethylene oxide-added bisphenol A methacrylate, (viscosity: 590 mPa・ S / 25 ° C)
M110: Allonics M-110, manufactured by Toagosei Co., Ltd., paracumylphenol ethylene oxide modified acrylate (viscosity: 130 mPa · s / 25 ° C.)
LR8883X: Lucirin LR8883X, photo radical generator manufactured by BASF Corporation, ethyl-2,4,6-trimethylbenzoylethoxyphenyl osphine oxide DA1173: Darocur 1173, manufactured by Ciba Specialty Chemicals Co., Ltd., 2-hydroxy- 2-methyl-1-phenyl-propan-1-one 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 sectional view of the embossing roller 13 is shown in FIG.

  A die coater was used as the coating means 12. As the coating head 12C of the coating means 12, an extrusion type was used.

  As the coating solution F (resin solution), each solution described in the table of FIG. 2 described above was used. 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, a sheet W on which a concavo-convex pattern was formed corresponding to each of the examples and comparative examples shown in the table of FIG.

[Evaluation of applicability]
The coating surface after the resin solution was supplied onto the sheet W by the coating means 12 was judged by visual evaluation. The case where the coating could be performed without defects such as streaks and unevenness was rated as “◯”, and the case where defects such as streaks and unevenness had occurred was evaluated as “poor”.

[Evaluation of curability]
About the embossed sheet produced with the above-mentioned embossed sheet production apparatus, the curability was judged by lightly touching the UV curable resin surface of the embossed sheet. The case where the surface was sufficiently cured and did not undergo deformation, scratches, etc. was rated as ○.

[Measurement of refractive index]
The liquid curable composition was applied onto a glass plate using a spinner and dried in an oven set at 100 ° C. for 1 minute. This film was irradiated with ultraviolet rays having an intensity of 1000 mJ / cm ² under a nitrogen atmosphere to obtain a cured film. The refractive index of this cured film at 25 ° C. was measured using an Abbe refractometer.

  Hereinafter, for each resin liquid, the results of producing an embossed sheet by the above production method are summarized in the table of FIG. Moreover, the refractive index was measured about each resin liquid corresponding based on said evaluation method. The results are also summarized in the table of FIG.

  In the table of FIG. 2, Example 1 is an example using the compounds of the above-described chemical formulas (1) and (4), and Example 2 has the chemical formulas (1), (3) and ( Example 4 is an example using the compound of Example 4, Example 3 is an example using the compound of Formulas (1) and (4) described above, and Example 4 is an example using Formulas (1), ( Example 2 uses the compounds of 2) and (4), and Example 5 is an example of using the compounds of the chemical formulas (1), (2) and (4) described above. All the evaluations are good, and values that satisfy the refractive index are obtained.

  In the table of FIG. 2, Comparative Example 1 is one in which the compound of formula (1) was not used in the composition of Example 1. As a result, the applicability and curability were both good, but the refractive index was low and the result was NG.

  In the table of FIG. 2, Comparative Example 2 is a case where the solvent (MEK) is removed from the composition of Example 1 (other composition ratios are the same). As a result, although both the refractive index and the curability were evaluated satisfactorily, the viscosity was high and the applicability was deteriorated to be NG.

  In the table of FIG. 2, Comparative Example 3 is obtained by replacing the initiator LR8883X of Example 1 with DA1173. As a result, the refractive index and the applicability were both good, but they volatilized during the heat drying and the curability deteriorated to become NG.

  From the above results, the effect of the present invention was confirmed.

The conceptual diagram which shows the structure of the manufacturing apparatus of the embossed sheet | seat to which this invention is applied. Table showing the formulation of each resin solution Sectional view showing the outline of the embossing roller Sectional view showing the outline of the embossed sheet 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 Removing means, H ... protective film, W ... sheet

Claims (6)

It is used in a method for producing a concavo-convex sheet in which a concavo-convex mold is closely attached to a sheet-like body coated with a liquid radiation curable composition on the surface, and the concavo-convex shape of the concavo-convex surface is transferred to the surface of the sheet-form body Said radiation curable composition comprising:
A radiation curable composition comprising the following (A), (B), (C) and (D).
(A) Compound having a structure represented by the following chemical formula 1

However, R1 is H or CH _3, m and n is 1 or 2.
(B) An acrylate or methacrylate compound having one or more aromatic rings (C) A compound having one or more polymerizable ethylenically unsaturated bonds in the molecule other than (A) and (B) (D) Photopolymerization initiation Agent The radiation curable composition according to claim 1, wherein (B) is a compound comprising one or more of the following chemical formula 2, chemical formula 3, and chemical formula 4.

However, R1 is H or CH _{3, X 1} is Cl or Br. p is an integer of 1 to 3.

However, R1 is H or CH _{3, X 1} is Cl or Br. q is an integer of 1 to 3.

However, R1 is H or CH _{3, X 2} is Cl or Br. r is an integer of 0 to 2, and s is an integer of 0 to 3. R2 _{is, H,} CH _3, alkyl group of C 1 ~C _8, Ph or -C _(CH 3) is -Ph.
(C) Compound having one or more polymerizable ethylenically unsaturated bonds in the molecule other than (A) and (B) (D) Photopolymerization initiator   (D) is 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, or bis- (2,6-dimethoxybenzoyl) -2,4,4. The radiation curable composition according to claim 1, which is trimethylpentylphosphine oxide.   The radiation curable composition according to any one of claims 1 to 3, wherein a refractive index of the radiation curable composition after transfer formation is 1.58 or more.   The radiation curable composition of any one of Claims 1-4 in which the said radiation curable composition at the time of application | coating contains 10 weight% or more of organic solvents. The radiation curable composition according to any one of claims 1 to 5, wherein the viscosity of the radiation curable composition at the time of application is 100 mPa · s or less.

Images