JP2008230057A - Sheet-like molding and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet-like molding with successful molding precision and a fine uneven shape. <P>SOLUTION: The sheet-like molding includes a support 11 and a resin layer 12 which is arranged on one of the main surface sides of the support 11 and has an uneven shape on the opposite surface, to the support side surface, of the resin layer 12. The manufacturing method of the sheet-like molding includes the steps of: superposing a coating material layer with a radiation-curable resin composition containing a radiation-curable resin over the support; transferring the uneven shape of an uneven surface of a molding die to the coating material layer by bringing the coating material layer into contact with the coating material layer; and curing the radiation-curable resin contained in the coating material layer. The uncured radiation-curable resin contains at least, one kind of monomer A selected from the group consisting of a monofunctional vinyl monomer and a monofunctional (meth)acryl monomer, and at least, one kind selected from the group consisting of a polyfunctional (meth)acryl monomer and a polyfunctional (meth)acryl oligomer. The viscosity of the radiation-curable resin composition at 25°C is 3 to 100 mPa s. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sheet-like molded article having fine irregularities on at least one main surface and a method for producing the same.

  A molded body having fine irregularities on at least one main surface is an antireflection film, a diffusion sheet, an optical film such as a brightness enhancement sheet, a light guide plate, a diffraction grating, a patterned medium, an optical recording medium, an optical element, a hologram, Widely used in the fields of micro-channels, building materials, decorations and polishing tapes. In the field of optical films such as antireflection films and diffusion sheets, there is a demand for further miniaturization of the concavo-convex shape, and there is a strict requirement for reliability regarding molding accuracy and the like.

  An anti-glare film having fine irregularities on the main surface on which light is incident uses light scattering on the irregular surface to further suppress reflection of light. The antireflection film is used by being attached to a display unit such as a liquid crystal display panel or a CRT, for example, thereby suppressing external light and peripheral objects from being reflected on the display unit. The antireflection film usually includes a low refractive index layer made of a material having a relatively low refractive index, a high refractive index layer having a refractive index higher than that of the low refractive index layer, and a translucent substrate. It has a structure in which layers are stacked in this order from the light incident side. The high refractive index layer is sometimes called a hard coat layer.

  The antireflection film with fine irregularities on the main surface on which light is incident can suppress the reflection of light more, but the entire image looks white like ground glass. Has the disadvantage of reducing the thickness. However, there is a report that an excellent antireflection function can be obtained by setting the pitch of the concavo-convex shape to a submicron order below the visible light wavelength (see Non-Patent Document 1, etc.), and the reflection is improved by further miniaturization of the concavo-convex shape. Efforts are being made to further improve prevention.

  There are various methods for forming a surface having a fine concavo-convex shape, but a method using a mold having a concavo-convex shape on the surface is simple and economical. As this method, a method for producing a sheet-like molded body having an uneven surface continuously using an embossing roll as described below has been proposed.

  In an example of the manufacturing method of a sheet-like molded object, the coating material containing an active energy ray hardening-type resin composition is supplied on a sheet-like transparent base material. Subsequently, these are conveyed between the embossing roll which has an uneven | corrugated surface, and a support roll, and the active energy ray hardening-type resin composition on the said base material is pressed on an embossing roll. The active energy ray-curable resin composition in this state is irradiated with active energy rays to cure the active energy ray-curable resin (for example, Patent Document 1).

  In another example of the manufacturing method of a sheet-like molded object, the coating material containing an active energy ray hardening-type resin composition is apply | coated on the said uneven surface of the embossing roll which has an uneven surface. Next, the active energy ray-curable resin composition is irradiated with the active energy ray-curable resin composition in a state where the sheet-like base material is superimposed on the active energy ray-curable resin composition applied to the embossing roll, and the active energy ray-curable resin is irradiated. The composition is cured (see, for example, Patent Document 2).

  Patent Documents 1 and 2 describe that it is preferable to use a paint having a relatively low viscosity from the viewpoint of coating workability. As a method for adjusting the viscosity, an active energy ray-curable resin composition is used, for example, ethyl alcohol. It is disclosed to use a solvent such as

  For the active energy ray-curable resin, a resin having a relatively high viscosity composed of a urethane acrylate oligomer and dipentaerythritol hexaacrylate may be used (see, for example, Patent Document 3). Moreover, ultraviolet curable resin, such as an acrylic resin with a viscosity of 400 mPa * s and an epoxy resin with a viscosity of 100-5000 mPa * s, may be used for the said active energy ray hardening-type resin (for example, patent document 4). In addition, in the process of manufacturing a matte decorative plate having an uneven surface, an acrylic resin having a viscosity of 300 mPa · s may be used as an electron beam curable resin that is an example of an energy beam curable resin (for example, Patent Document 5). ).

  Patent Document 3 describes that when the viscosity of the paint is low, it is difficult to control the thickness of the coating film and it flows on the support film, which is not preferable. Patent Documents 4 and 5 specifically disclose preferred resin viscosity ranges, but all have high viscosities.

Fine irregularities are also used for optical disks. The optical disk has a track groove having a concave and convex shape on the order of submicrons. In an optical disk, information is recorded by forming a pit row composed of minute light spots in the track groove. In order to improve the recording density, further miniaturization of the track groove is desired along with further miniaturization of the light spot. Note that the substrate having the track groove is manufactured by an injection molding method using a mold or the like.
PBClapham and M.C.Hutley, Nature (London) 244,282-282 (1973) Japanese Patent No. 3016638 Japanese Patent No. 3490099 Japanese Patent No. 2610463 JP 2002-225133 A JP-A-11-115140

  However, in the manufacturing methods described in Patent Documents 1 to 5, the precision of forming fine uneven shapes was insufficient.

  In the present invention, a sheet-like molded body having a fine uneven shape with good molding accuracy is provided.

  The method for producing a sheet-like molded body of the present invention includes a support and a resin layer disposed on one main surface side of the support, and a resin layer having an uneven surface on the opposite surface of the support side. A method for producing a shaped molded article, wherein a coating layer containing a radiation curable resin composition containing a radiation curable resin and a support are in contact with the coating layer having a concavo-convex surface. After the uneven shape of the uneven surface of the mold is transferred to the paint layer, the radiation curable resin contained in the paint layer is cured to form the resin layer as the resin layer. The radiation curable resin in an uncured state including a process includes at least one monomer A selected from the group consisting of a monofunctional vinyl monomer or a monofunctional (meth) acrylic monomer, a polyfunctional (meth) acrylic monomer, and a polyfunctional (meth) acrylic monomer Sensuality ( Data) and at least one selected from the group consisting of acrylic oligomer, the viscosity of the radiation curable resin composition at 25 ° C., characterized in that it is a 3~100mPa · s.

  The sheet-like molded body of the present invention comprises a support and a resin layer that is disposed on one main surface side of the support, and a resin layer having an uneven surface on the opposite side of the surface on the support side. The resin layer is brought into contact with a mold having an uneven surface in a state where the coating layer containing the radiation curable resin composition containing the radiation curable resin and the support overlap. After transferring the uneven shape of the uneven surface of the mold to the paint layer, the radiation curable resin in an uncured state is obtained by curing the radiation curable resin contained in the paint layer, A small number selected from the group consisting of at least one monomer A selected from the group consisting of monofunctional vinyl monomers or monofunctional (meth) acrylic monomers, and polyfunctional (meth) acrylic monomers and polyfunctional (meth) acrylic oligomers. Both and a one, the viscosity of the radiation curable resin composition at 25 ° C., characterized in that it is a 3~100mPa · s.

  According to the present invention, there is provided a sheet-like molded body having a fine uneven shape with good molding accuracy.

  In order to obtain a sheet-like molded body having a fine uneven shape, it is necessary that the radiation curable resin composition contained in the paint layer enters every corner of the mold. Moreover, in order to form fine uneven | corrugated shape, it is preferable to form a thin coating layer. However, as described in Patent Documents 3 to 5, it is difficult to form a thin paint layer with a high-viscosity paint. Moreover, as described in Patent Documents 1 and 2, if the radiation curable resin composition is diluted with a solvent to reduce the viscosity of the coating material, the coating suitability is improved. However, the viscosity of the paint from which the solvent has been removed by drying, that is, the viscosity of the radiation curable resin composition contained in the paint layer has not been taken into consideration, Problems such as the radiation curable resin composition not reaching every corner of the mold cannot be improved.

  As a result of intensive studies to produce a sheet-like molded article having fine irregularities with good molding accuracy, the inventors have selected the type of radiation-curable resin in the radiation-curable resin composition and molded The above problem was solved by setting the viscosity of the radiation curable resin composition contained in the immediately preceding coating layer to a predetermined value.

  Below, an example of the sheet-like molded object of this invention and an example of the manufacturing method are demonstrated using FIGS.

  As shown in FIG. 1A, the sheet-like molded body 10 of the present embodiment includes a support body 11 and a resin layer 12 disposed on the support body 11. The surface opposite to the main surface of the resin layer 12 on the support 11 side has irregularities.

  The method for manufacturing the sheet-like molded body 10 includes a resin layer forming step. In the resin layer forming step, in a state where the coating layer containing the radiation curable resin composition containing the radiation curable resin and the support are overlapped, the coating layer is brought into contact with a molding die having an uneven surface and the molding die. The uneven shape of the uneven surface is transferred to the paint layer. Next, the radiation-curable resin contained in the paint layer is cured to make the paint layer a resin layer. As the mold, for example, an embossing roller that can continuously manufacture a sheet-like sheet-shaped molded body and can efficiently manufacture the sheet-shaped molded body is preferable. The said resin layer formation process can be performed like the example shown in FIGS.

  In the example shown in FIG. 2, the belt-like support 2 is sequentially sent out by the feed roll 1, and then a coating material containing a radiation curable resin composition is supplied from the coater 3 onto the support 2. The above-mentioned paint is applied to the main surface. If the paint contains a diluting solvent, the support 2 coated with the paint is conveyed into a dryer (not shown) to remove the diluting solvent from the paint.

  Thus, the uneven surface of the embossing roll 4 is pressed against the coating layer in a state where the coating layer containing the radiation-curable resin composition in an uncured state and the support are overlapped, and the uneven surface of the embossing roll 4 is pressed. The uneven shape is transferred. In this state, the coating layer is irradiated with radiation such as ultraviolet rays through the support 2 by the radiation irradiation device 5, and the radiation curable resin contained in the coating layer is cured, so that the coating layer becomes a resin layer.

  The embossing roll 4 is pressed against the coating layer by a pair of support rolls 6 arranged so as to sandwich the embossing roll 4. Since the shielding plate 7 is disposed in the vicinity of the radiation irradiating device 5, it is suppressed that the portion that should not be irradiated with radiation is irradiated.

  Although the support roll 6 may be used to press the embossing roll 4 against the paint layer using the tension of the support 2, the use of the support roll 6 is preferable because the shape is stable. When the heat generated by the radiation irradiation damages the support 2, the embossing roll 4 and / or the support roll 6 may have a cooling function as necessary.

  In the example shown in FIG. 3, the paint is supplied from the coater 3 on the uneven surface of the embossing roll 4, and a paint layer is formed on the uneven surface. In a state where the coating layer and the belt-like support 2 sequentially fed by the feeding roll 1 overlap, the uneven surface of the embossing roll 4 is pressed against the coating layer by the supporting roll 6, and the unevenness of the embossing roll 4 is applied to the coating layer. Transfer the shape. In this state, the coating layer is irradiated with radiation such as ultraviolet rays by the radiation irradiation device 5 through the support 2 to cure the radiation curable resin contained in the coating layer, and the coating layer becomes a resin layer.

  In the example shown in FIG. 4, the embossing roll is made of a material that transmits radiation, and the radiation irradiation device 5 is disposed inside the embossing roll. In this example, since radiation is applied to the coating layer or the like through the embossing roll 4, the coating layer can be cured even when the support 2 is made of a material that does not transmit radiation.

  Next, details of the paint used in the method for producing a sheet-like molded body of the present embodiment will be described.

  The paint layer is obtained by applying a paint containing a radiation curable resin composition and, if necessary, a diluting solvent, and then removing the diluting solvent from the coating film by drying. In addition, although the dilution solvent which dilutes a radiation curable resin composition may be added in order to make the applicability | paintability of a coating material better, it is not necessarily required.

  In addition to the radiation curable resin, the radiation curable resin composition may include a photoinitiator, a sensitizer, an accelerator, a polymerization inhibitor, a leveling agent, a release agent, a colorant, or a filler, if necessary. May be included. Moreover, in order to make application | coating suitability more favorable, the coating material may contain the dilution solvent which dilutes a radiation curable resin composition as needed.

  The radiation curable resin is composed of at least one monomer A selected from the group consisting of a monofunctional vinyl monomer or a monofunctional (meth) acrylic monomer, a polyfunctional (meth) acrylic monomer, and a polyfunctional (meth) acrylic oligomer. And at least one selected from the group. And the viscosity of the radiation curable resin composition in 25 degreeC is 3-100 mPa * s.

  A general radiation curable resin is composed of a monofunctional monomer and a polyfunctional monomer or polyfunctional oligomer. In general, it is the polyfunctional monomer or polyfunctional oligomer that mainly controls the properties of the cured product of the radiation curable resin. Monofunctional monomers are used as diluents for viscosity adjustment. Therefore, the lower the viscosity of the radiation curable resin, the more difficult it is to secure the desired strength of the resin layer, specifically, the pencil hardness measured based on JIS K 5600-5-4. .

  In the method for producing a sheet-shaped molded article of this embodiment, at least one monomer A selected from the group consisting of a monofunctional vinyl monomer or a monofunctional (meth) acrylic monomer, a polyfunctional (meth) acrylic monomer, and a polyfunctional ( A radiation curable resin containing at least one selected from the group consisting of (meth) acrylic oligomers is used. Moreover, the viscosity of the radiation curable resin composition contained in the coating layer is 3 to 100 mPa · s.

  Thus, if the radiation curable resin is selected and the viscosity of the radiation curable resin composition is set to a predetermined value, the radiation curable resin composition can penetrate into every corner of the mold, and There is no sticking to the mold and it can be released smoothly. And as shown in the Example mentioned later, the intensity | strength of hardened | cured material (resin layer) and the low viscosity of a radiation curable resin can be made compatible, and the shaping | molding body which has fine uneven | corrugated shape with favorable shaping | molding precision is obtained. be able to.

  The viscosity at 25 ° C. of the paint containing the radiation curable resin composition is preferably 3 to 100 mPa · s. If the viscosity of the paint is in this range, for example, even when a paint layer having a thickness of 10 μm or less is formed, the paint can be applied satisfactorily and the application streak caused by a leveling defect or the like can be achieved. , The occurrence of uncoated portions (voids) can be suppressed. For the same reason, the viscosity of the paint at 25 ° C. is more preferably 5 to 50 mPa · s. Further, when the viscosity at 25 ° C. of the paint is 100 mPa · s or less, even if the transfer speed is high, the bubbles in the paint can be easily removed, and the uneven surface of the embossing roll can be transferred to the paint layer. Hard to cause defects.

  The resin layer thickness is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 10 μm or less in order to obtain a molded article having a fine uneven shape.

  As a method for controlling the viscosity of the radiation curable resin composition contained in the coating layer, at least one selected from the group consisting of monomer A, a polyfunctional (meth) acrylic monomer, and a polyfunctional (meth) acrylic oligomer; A method of controlling the mixing ratio of these is mentioned.

  Next, at least one monomer A selected from the group consisting of a monofunctional vinyl monomer or a monofunctional (meth) acrylic monomer contained in the radiation curable resin composition, a polyfunctional (meth) acrylic monomer, and a polyfunctional (meta) ) Specific examples of the acrylic oligomer will be described.

  Examples of the monofunctional vinyl monomer include vinyl pyrrolidone and vinyl formamide. Monofunctional (meth) acrylic monomers include acryloylmorpholine, tetrahydrofurfuryl (meth) acrylate, hydroxyethyl (meth) acrylate, dimethylacrylamide, isobornyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) Examples include acrylate, ethoxydiethylene glycol (meth) acrylate, methoxy-triethylene glycol (meth) acrylate, and methoxydipropylene glycol (meth) acrylate. Since these monomers A have a functional group such as a heterocyclic ring, an amide group, a hydroxyl group, or a methoxy group, the adhesion of the resin layer obtained by curing the coating layer containing these monomers to the support is good. Of these, vinylpyrrolidone, dimethylacrylamide, acryloylmorpholine, and tetrahydrofurfuryl acrylate are more preferable in consideration of the viscosity, curability, hardness of the resin layer, adhesion to the support, and the like of the radiation curable resin composition. Vinylpyrrolidone, dimethylacrylamide, and acryloylmorpholine, which are excellent in balance with respect to viscosity, curability, hardness of the cured product, and adhesion to the support, are particularly preferred.

  As the polyfunctional (meth) acrylic monomer, 2-hydroxy-3- (meth) acryloyloxypropyl tri (meth) acrylate, 1,6-hexane dilol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Examples include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and dipentaerythritol hexa (meth) acrylate.

  Examples of the polyfunctional (meth) acrylic oligomer include (meth) acrylic oligomers such as AH-600 and UA306H manufactured by Kyoeisha Chemical, U-4HA, U-6HA and U-6LPA manufactured by Shin-Nakamura Chemical.

  When it is contained in the radiation curable resin composition for forming the resin layer, the curing is performed well. Moreover, at least 1 sort (s) chosen from the group which consists of a polyfunctional (meth) acryl monomer and a polyfunctional (meth) acryl oligomer contributes to the improvement of the hardness of a resin layer. Among these, pentaerythritol triacrylate, dipentaerythritol hexaacrylate and acrylic oligomer are particularly preferable in consideration of curability, hardness of the resin layer, adhesion of the resin layer to the support, and the like. At least one selected from the group consisting of a polyfunctional (meth) acrylic monomer and a polyfunctional (meth) acrylic oligomer has three or more reactive functional groups, so it has better curability and higher curing. Since the crosslinking density is obtained, the hardness of the cured product can be further increased.

  The mixing ratio of the monomer A and at least one selected from the group consisting of a polyfunctional (meth) acrylic monomer and a polyfunctional (meth) acrylic oligomer is such that the radiation curable resin composition has a viscosity of 3 to 100 mPa · For example, the weight ratio is preferably 10:90 to 80:20 so as to be s. In this case, the uneven surface of the embossing roll has good transferability to the coating layer, and the mechanical strength of the resin layer is sufficiently secured, which is preferable.

  The content of the radiation curable resin contained in the radiation curable resin composition varies depending on the type of the radiation curable resin, but usually 80 to 99 parts by weight when the radiation curable resin composition is 100 parts by weight. It is preferable that it is about.

Of In selecting radiation curable resin, curing from the viewpoint of productivity, preferably those cured at 300 mJ / cm ² or less of ultraviolet light intensity, more preferably those which cure at 150 mJ / cm ² or less, at 50 mJ / cm ² or less What is to be done is even more preferred.

  The flash point of the radiation curable resin is preferably 70 ° C or higher. This is because if the flash point is lower than 70 ° C., the risk of ignition increases.

  The degree of necessity of the photoinitiator varies depending on the type of radiation applied to the coating layer. In particular, when ultraviolet rays or visible light is used as an energy source for the curing reaction, the radiation curable resin composition preferably contains a photoinitiator.

  There is no restriction | limiting in particular as a photoinitiator, A general thing can be used. As the photoinitiator, a photoradical polymerizer is preferable. Examples of the photoradical polymerizer include α-diketones such as benzyl and diacetyl, acyloins such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether. Acylloin ethers, thioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, thioxanthone such as thioxanthone-4-sulfonic acid, benzophenone, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis Benzophenones such as (diethylamino) benzophenone, Michler's ketones, acetophenone, 2- (4-toluenesulfonyloxy) -2-phenylacetophenone, p-dimethylaminoacetophenone, α, α′-dimethoxya Toxibenzophenone, 2,2′-dimethoxy-2-phenylacetophenone, p-methoxyacetophenone, 2-methyl [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1 Acetophenones such as-(4-morpholinophenyl) -butan-1-one, quinones such as anthraquinone and 1,4-naphthoquinone, phenacyl chloride, trihalomethylphenyl sulfone, tris (trihalomethyl) -s-triazine, etc. And peroxides such as di-t-butyl peroxide. These may be used alone or in combination of two or more.

  Irradiation of ultraviolet rays onto the coating layer may be performed through the support, and therefore it is preferable to select an appropriate initiator according to the wavelength of light transmitted through the support. Specifically, it is preferable to select a photoinitiator that absorbs light in a wavelength region that does not overlap with the absorption wavelength of the support. For example, when the support material is polyethylene terephthalate or polyethylene naphthalate, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, bis (2,4,6-trimethyl) It is preferable to select a photoinitiator such as benzoyl) -phenylphosphine oxide, 2-methyl-1- (4-methylthio) phenyl) -2-morpholinopropan-1-one. Commercially available products include Irgacure 369 (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1), Irgacure 819 (bis (2,4,6-trimethylbenzoyl) -phenylphosphine). Oxide), Irgacure 907 (2-methyl-1- (4-methylthio) phenyl) -2-morpholinopropan-1-one) (both manufactured by Ciba-Gaiky). In particular, it is effective to use 2-methyl-1- (4-methylthio) phenyl) -2-morpholinopropan-1-one in combination with 2,4-diethylthioxanthone or 2-chlorothioxanthone.

  When the coating material contains a dilution solvent that dilutes the radiation curable resin composition, the dilution solvent is preferably added so that the viscosity of the coating material at 25 ° C. is 3 to 100 mPa · s. There is no restriction | limiting in particular about the kind of dilution solvent, For example, what is necessary is just to use conventionally well-known dilution solvents, such as methyl ethyl ketone, toluene, and dimethylformamide.

  Examples of the method for forming the paint layer include a roll coating method, a curtain coating method, a sulfide auto method, a die coating method, a blade coating method, a bar coating method, a flow coating method, and a spray coating method. Among these, a roll coating method, a curtain coating method, a sulfide auto method, and a die coating method are preferable as the method for forming the coating layer, which enables the coating to be applied thinly and at high speed.

  The coating speed is 10 m / min or more, preferably 20 m / min, and more preferably 50 m / min or more. The upper limit of the coating speed is not particularly limited, but usually 200 m / min or less is appropriate because of the balance with the curing speed.

  The radiation used for curing the radiation curable resin is not particularly limited as long as it is a radiation that can cure the radiation curable resin, and examples thereof include an electron beam, ultraviolet rays, and visible light. Of these, ultraviolet rays and electron beams having high energy values are preferable.

  As the ultraviolet light source, for example, a high pressure mercury lamp, a metal halide lamp, or an LED is used. The LED is preferable because it has high energy efficiency and small thermal damage to the support. In order to improve the curability of the radiation curable resin, it is preferable that the irradiation with ultraviolet rays be performed in an atmosphere purged with nitrogen and adjusted to an oxygen concentration of 300 ppm or less as necessary.

  Although the preferable shape of the uneven surface of the resin layer varies depending on the use of the sheet-like molded body, in this embodiment, the average one-cycle length (D) of the unevenness is 0.01 μm to 50 μm, and the average height of the protrusions ( H) is 0.01 μm to 50 μm, and a sheet provided with a resin layer having a ratio (D / H) of the average one-cycle length (D) to the average height (H) of the unevenness of 0.01 to 100 This is useful for the production of a shaped article. Examples of such a concavo-convex shape include optical sheets such as diffusion sheets and brightness enhancement sheets, patterned media, and optical recording media. In particular, the average period length (D) of irregularities is 0.01 μm to 30 μm, the average height (H) is 0.01 μm to 30 μm, and the ratio (D / H) is 0.01 to 100. This is useful for the production of a sheet-like molded body provided with a resin layer.

The average one-cycle length (D) and average height (H) of the uneven surface of the resin layer are values obtained from an electron beam microscope (Hitachi SEM EDX-4500H) photographed image of the surface and cross section of the sheet-like molded body. (Shooting magnification: 2000 times, field of view: 45 μm × 45 μm). When the concavo-convex shape is a regular pattern, as shown in FIGS. 1 (a) and 1 (b), d is one period length, h is the height of the concavo-convex, and 20 points are measured, and the average As an average one-cycle length (D) and an average height (H). If unevenness is irregular, as shown in Figure _{1 (c), A 1,} A 2, A 3 each apex of the concave-convex shape, ... A _n, B ₁ each bottom, B _2, B _3. Name the points B _n and find the (x, y) coordinates of each point. Assuming that the coordinates of A ₁ are (xa ₁ , ya ₁ ) and the coordinates of B ₁ are (xb ₁ , yb ₁ ), the interval D ₁ between A ₁ and B ₁ is obtained by D ₁ = xb ₁ −xa _1. . In this case, the average one-cycle length D of the concavo-convex shape is obtained as D = (d ₁ + d ₂ + d ₃ +... + D _n ) / n. Similarly, the height difference H ₁ between A ₁ and B ₁ is obtained by H ₁ = yb ₁ −ya ₁ , and the average height H of the concavo-convex shape is H = (h ₁ + h ₂ + h ₃ +... + H _n ) / n.

  The ratio (P / H) between the average thickness (P) of the resin layer 12 and the average height (H) of the unevenness is not particularly limited, but is preferably 1 to 1000 from the economical viewpoint. More preferably, it is -200. When (P / H) exceeds 1000, the thickness of the portion on the support side that does not constitute a fine uneven shape in the resin layer is increased, and an unnecessary resin is used. Here, the average thickness (P) of the resin layer 12 is a value measured as follows.

Ten sheet-like molded bodies are stacked, and the average thickness of the laminate X is measured. On the other hand, only 10 supports are stacked, and the average thickness of the laminate Y is measured. Using these measured values, the average thickness (P) of the sheet-like molded body was calculated by the following formula. However, the average thickness of the laminated body X and the laminated body Y was measured by measuring the thickness of each of the laminated body X and the laminated body Y using a micrometer (minimum scale: 0.1 μm) and averaging the values. And asked.
(Formula 1)
Average thickness (P) of sheet-like molded product = (Average thickness of laminate X−Average thickness of laminate Y) / 10

  The coating thickness is preferably controlled so that the thickness of the resin layer is preferably 50 μm or less, more preferably 30 μm or less, and most preferably 10 μm or less.

  For the support 11, for example, a conventionally known flexible translucent film or the like is used. Examples of the material of the support 11 include polyethylene terephthalate, polyethylene naphthalate, polyamide, polyaramid, polyimide, polycarbonate, polyphenylene sulfide, polysulfone, polypropylene, polymethyl methacrylate, polyvinyl alcohol, cellulose triacetate, and cycloolefin polymer. It is done. Among these, the support 11 preferably contains polyethylene terephthalate from the viewpoints of mechanical strength, dimensional stability, heat resistance, and the like.

  The thickness of the support 11 is not particularly limited and varies depending on the application, but is usually preferably 1 to 200 μm. In particular, when the thickness of the support 11 is 3 to 20 μm, the method for producing a sheet-like molded body of this embodiment is useful.

  In order to improve the adhesion of the resin layer 12 to an adjacent layer, for example, the surface of the support 11 in contact with the resin layer 12 may be subjected to a surface treatment such as corona or plasma treatment. 11 may be provided with an easy adhesion layer made of polyurethane, polyester or the like.

  The pencil hardness measured based on JIS K 5600-5-4 of the resin layer 12 is preferably F or more, and more preferably H or more. If it is F or more, the surface of the resin layer 12 is not easily damaged even if the transfer speed is as high as about 50 to 200 m / min.

  The adhesiveness of the resin layer to the adjacent layer is preferably 0 or 1, more preferably 0, when evaluated by the cross-cut method based on JIS 5600-5-6.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to the examples.

<Examples 1-10, Comparative Examples 1-3>
Paints A to J having the compositions shown in Table 1 were prepared. Numerical values related to the compositions of the paints A to J mean parts by weight. The sheet-like molded bodies of Examples 1 to 10 and Comparative Examples 1 to 3 were manufactured by an example of the method for manufacturing the sheet-like molded body described with reference to FIG.

Details of each composition are as follows.
Vinylpyrrolidone (monofunctional acrylic monomer)
Dimethylacrylamide (monofunctional acrylic monomer)
Methyl methacrylate (monofunctional methacrylic monomer)
Acryloyl morpholine (monofunctional methacrylic monomer)
Pentaerystol triacrylate (trifunctional acrylic monomer)
Dipentaerystol hexaacrylate (hexafunctional acrylic monomer)
Urethane acrylate UA-306 (Kyoeisha Chemical, pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer 6-functional oligomer)
Irgacure 184 (photoinitiator, manufactured by Ciba Gaiky, 1-hydroxy-cyclohexyl-phenyl-ketone)
Irgacure 907 (photoinitiator, Ciba Gaiky, 2-methyl-1- (4-methylthio) phenyl) -2-morpholinopropan-1-one))
2,4-diethylthioxanthone (photoinitiator)

First, a paint layer was formed by applying a paint to one main surface of a 10 μm thick PET film by a roll coating method. The coating speed was 20 m / min in Examples 1 to 8 and Comparative Examples 1 and 2, 40 m / min in Example 9, 80 m / min in Example 10, and 10 m / min in Comparative Example 3. The paint was applied so that the thickness of the paint layer was about 1 to 5 μm. Thereafter, the embossing roll is pressed against the coating layer to transfer the concavo-convex shape of the concavo-convex surface of the embossing roll, and then the coating layer is irradiated with ultraviolet rays by an ultraviolet irradiator to cure the radiation curable resin contained in the coating layer. . The irradiation amount of ultraviolet rays was 300 mJ / cm ² .

  For coating application, a micro gravure roll manufactured by Yurai Seiki with a diameter of 20 mm, an oblique line type, a cell angle of 45 °, and 250 lines / inch was used. Further, the embossing roll has an average period length (D) of 0.8 μm and an average unevenness height (H) of 0.05 μm, and has an uneven surface corresponding to the unevenness of the form shown in FIG. The possessed metal roll was used.

  The viscosity of the radiation curable resin composition, the thickness of the resin layer, the pencil hardness of the uneven surface of the sheet-shaped molded body, the adhesiveness between the resin layer and the support, the curability and the moldability were evaluated as follows, The results are shown in Table 1.

<Viscosity of radiation curable resin composition>
The viscosity of the radiation curable resin composition at 25 ° C. was measured with an E-type viscometer (rotation speed: 10 rpm) manufactured by Toki Sangyo.

<Thickness of resin layer>
The thickness of the resin layer was calculated from the above (Formula 1).

<Pencil hardness>
The pencil hardness of the sheet-like molded body was measured based on JIS K 5600-5-4.

<Adhesiveness>
The adhesiveness of the resin layer to the support was measured by a cross-cut method based on JIS 5600-5-6. The degree of peeling was evaluated on a scale of 0-5. “0” means that no peeling is observed, and the larger the number, the greater the degree of peeling.

<Curing property>
After forming a paint layer on the support using a bar coater (wire wrapped around a bar) made by Toyo Seiki, a 188 μm-thick PET film was attached to this paint layer, and UV light was passed through this PET film. Irradiation was performed. The amount of ultraviolet light required until the tackiness disappeared was measured with an illuminometer (UV Power Pack manufactured by EIT). In addition, it means that curability is so high that there are few amounts of ultraviolet rays. The presence or absence of tackiness was confirmed by finger touch.

<Defects and formability>
The presence or absence of coating defects in the sheet-like molded product was visually observed in 20 visual fields (measurement visual field: 10 cm × 10 cm), and fine molding defects (leveling defects, etc. due to imperfect leveling) 20 fields were observed (measurement magnification: 2000 times, measurement field: 45 μm × 45 μm) and evaluated according to the following criteria.
○: No defect (no defect observed in 20 fields of view)
Δ: Slightly flawed (observation of defects in 1 to 2 fields in 20 fields of view)
X: Defects (observation of defects in 3 to 20 fields in each of 20 fields)

At least one monomer A selected from the group consisting of monofunctional vinyl monomers or monofunctional (meth) acrylic monomers, and at least one selected from the group consisting of polyfunctional (meth) acrylic monomers and polyfunctional (meth) acrylic oligomers In Examples 1 to 10 using a radiation curable resin composition containing a seed and having a viscosity at 25 ° C. in the range of 3 to 100 mPa · s, all are cured with an ultraviolet light amount of 40 to 150 mJ / cm ^2. The curability was good. Moreover, the result of the adhesiveness test by pencil hardness and the crosscut method was also favorable. Moreover, as a result of observing the moldability with an electron microscope, the concavo-convex shape was formed with high accuracy in the sheet-like molded bodies of Examples 1 to 10. In addition, in the sheet-like formed body of Example 9 in which the coating speed was 40 m / min and Example 10 in which the coating speed was 80 m / min, the uneven shape was accurately formed.

  On the other hand, in the sheet-like molded body of Comparative Example 1 in which the viscosity of the radiation curable resin is higher than 100 mPa · s, there are found molding defects such as coating defects and bubble entrapment that may be caused by streaks during coating. It was. Further, as shown in the results for Comparative Example 3, when the viscosity of the radiation curable resin is higher than 100 mPa · s, even when the coating speed is slowed down to 10 m / min, for example, coating defects and molding defects are observed. It was. Further, in the case-like molded body of Comparative Example 2 in which the viscosity of the radiation curable resin is lower than 3 mPa · s, the pencil hardness is 2B or less, and as a result of the adhesion test by the cross-cut method, peeling is observed, and the hardness Both adhesion and adhesion were insufficient. Further, the curability was also poor, and when the moldability of the molded product was observed, no coating defects were observed, but there were molding defects considered to be caused by poor curing.

  As described above, in the method for producing a sheet-shaped molded article of the present invention, the radiation curable resin is at least one monomer A selected from the group consisting of a monofunctional vinyl monomer or a monofunctional (meth) acrylic monomer, Since the viscosity of the radiation curable resin composition at 25 ° C. is 3 to 100 mPa · s, including at least one selected from the group consisting of functional (meth) acrylic monomers and polyfunctional (meth) acrylic oligomers, The coating property, moldability, and curability of the paint are all excellent, whereby a molded product having fine irregularities can be produced at high speed and with high accuracy.

  According to the present invention, it is possible to provide a sheet-shaped molded body having a fine concavo-convex shape with good molding accuracy. Therefore, the sheet-shaped molded body and the manufacturing method thereof according to the present invention include an antireflection film, a diffusion sheet, and a brightness enhancement sheet. It is useful in the fields of optical films such as optical guides, light guide plates, diffraction gratings, patterned media, optical recording media, optical elements, holograms, microchannels, building materials, decorative articles, and polishing tapes.

(A)-(c) is the conceptual diagram which showed an example of the sheet-like molded object of this invention. The conceptual diagram explaining an example of the manufacturing method of the sheet-like molded object of this invention The conceptual diagram explaining the other example of the manufacturing method of the sheet-like molded object of this invention The conceptual diagram explaining another example of the manufacturing method of the sheet-like molded object of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sending roll 2, 11 Support body 3 Coater 4 Embossing roll 5 Radiation irradiation apparatus 6 Support roll 7 Shielding plate 10 Sheet-like molded object 11 Resin layer

Claims (8)

A method for producing a sheet-like molded body comprising a support and a resin layer that is disposed on one main surface side of the support and has an uneven surface on the opposite side of the support-side surface,
In a state where the coating layer containing the radiation curable resin composition containing the radiation curable resin and the support are overlapped, the coating layer is brought into contact with a molding die having an uneven surface to form the uneven surface of the molding die. After transferring the concavo-convex shape to the paint layer, by curing the radiation curable resin contained in the paint layer, including a resin layer forming step in which the paint layer is the resin layer,
The radiation curable resin in an uncured state includes at least one monomer A selected from the group consisting of a monofunctional vinyl monomer or a monofunctional acrylic monomer, a polyfunctional (meth) acryl monomer, and a polyfunctional (meth) acryl oligomer. And at least one selected from the group consisting of
The manufacturing method of the sheet-like molded object characterized by the viscosity of the said radiation-curable resin composition in 25 degreeC being 3-100 mPa * s. The resin layer has an average one-cycle length (D) of irregularities of 0.01 μm to 50 μm,
The average height (H) of the convex portions is 0.01 μm to 50 μm,
2. The method for producing a sheet-like molded body according to claim 1, wherein a ratio (D / H) between the average one-cycle length (D) and the average height (H) is 0.01 to 100. 3.   The method for producing a sheet-like molded body according to claim 1, wherein the mold is an embossing roll. A sheet-like molded body provided with a support, and a resin layer disposed on one main surface side of the support, the surface opposite to the surface on the support having an uneven shape,
In the state in which the coating layer containing the radiation curable resin composition containing the radiation curable resin and the support are overlapped, the resin layer is brought into contact with the molding die having an uneven surface and the molding die. After transferring the uneven shape of the uneven surface to the paint layer, it is obtained by curing the radiation curable resin contained in the paint layer,
The radiation curable resin in an uncured state includes at least one monomer A selected from the group consisting of a monofunctional vinyl monomer or a monofunctional (meth) acrylic monomer, a polyfunctional (meth) acrylic monomer, and a polyfunctional (meth). Including at least one selected from the group consisting of acrylic oligomers,
A sheet-like molded article, wherein the radiation curable resin composition has a viscosity of 3 to 100 mPa · s at 25 ° C.   The sheet-like molded article according to claim 4, wherein the monomer A contains at least one selected from vinyl pyrrolidone, dimethylacrylamide, acryloylmorpholine, and tetrahydrofurfuryl acrylate.   Claims containing at least one selected from pentaerythritol triacrylate, dipentaerythritol hexaacrylate and acrylic oligomer as at least one selected from the group consisting of the polyfunctional (meth) acrylic monomer and the polyfunctional (meth) acrylic oligomer Item 5. A sheet-like molded article according to Item 4. The resin layer has an average one-cycle length (D) of irregularities of 0.01 μm to 50 μm,
The average height (H) of the convex portions is 0.01 μm to 50 μm,
The sheet-like molded product according to any one of claims 4 to 6, wherein a ratio (D / H) of the average one-cycle length (D) to the average height (H) is 0.01 to 100. .   The sheet-shaped molded body according to any one of claims 4 to 7, wherein the mold is an embossing roll.

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