JP2011247999A - Method for manufacturing molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a molded product having a highly regular structure with an order of 80 nm to 1000 μm which can be used for optical applications and is suitable for optical applications capable of performing advanced light controlling.SOLUTION: A method for manufacturing a molded product 100 having a phase separation structure comprising a matrix and a plurality of columnar structural bodies arranged regularly in the matrix and having a refractive index different from that of the matrix, comprising: a step of disposing a photopolymerizable composition 6; a step of disposing a photomask 10 in which mask holes are regularly arranged between the photosensitive composition and a light source 1; and a step of irradiating parallel light to the photopolymerizable composition from the light source in a state in which a fly-eye lens 4 is disposed between the light source and the photomask and curing the photopolymerizable composition to obtain a molded product. The light from the light source is irradiated to the photopolymerizable composition in a state in which the intensity distribution derived from the simple lens arrangement pattern of the fly-eye lens is finely overlapped.

Description

  The present invention relates to a method for producing a molded body, and more particularly, to a method for producing a molded body such as an optical sheet or an optical film used as an optical article having optical characteristics such as diffraction, scattering, interference, and polarization. These molded bodies can be used, for example, for improving the light emission efficiency of light-emitting elements such as organic electroluminescence elements and light-emitting diode elements, or for wavelength conversion films containing luminescent dyes.

Attempts have been made to form a one-dimensional or two-dimensional regular structure on a plastic film or sheet for use in optical applications such as a light control plate.
For example, as a method for forming a two-dimensional regular structure, there has been proposed a method in which block polymers are aligned and arranged in a plane perpendicular to the thickness direction of the film (Non-Patent Document 1).

  In addition, as a method for producing a film having a two-dimensional structure with high regularity, the photopolymerizable composition maintained in a film shape is irradiated with parallel light through a photomask as a first light irradiation step, and the second light A film in which columnar structures extending in a direction perpendicular to the surface of the matrix and having a refractive index different from that of the matrix are arranged with high regularity is produced by removing the photomask as an irradiation step and irradiating with parallel light. A method has been proposed (Patent Document 1).

  On the other hand, it has been suggested that a two-dimensional photonic crystal having a regular structure in the order of the wavelength of light can be used for improving the light emission efficiency of an organic electroluminescence element or a light emitting diode element (for example, Non-Patent Document 2). In a two-dimensional photonic crystal, it has been confirmed that light guided in the plane is forbidden by the two-dimensional band gap effect, so that light is emitted in a direction perpendicular to the plane.

JP 2008-134630 A

Maclomoecules 2003, 36, 3272-3288 Science, Vol.308, No.5726, pp.1296-1298 (2005)

  However, since the film manufactured by the method described in Non-Patent Document 1 has regularity in the order of nm, it is used as a general optical application requiring regularity of about 80 nm to 1000 μm. It was impossible.

  Moreover, in the manufacturing method described in Patent Document 1, in order to prevent the pattern of the photomask from deteriorating due to the diffraction in the mask hole of the photomask, the photomask is removed from the photopolymerizable composition in the first light irradiation step. It is necessary to arrange at a short distance of 100 μm or less.

  When the photomask pattern is miniaturized so as to reduce the interval between the columnar structures in the film, the deterioration of the pattern due to diffraction when parallel light passes through the photomask hole becomes more remarkable. For this reason, it is necessary to reduce the distance between the photomask and the photopolymerizable composition in accordance with the miniaturization of the photomask pattern. Therefore, in the method of Patent Document 1, there is a problem that it is gradually difficult to reduce the distance between the photomask and the photopolymerizable composition to a necessary distance when reducing the interval between the columnar structures.

  In addition, the two-dimensional photonic crystal described in Non-Patent Document 2 is only used to produce a sample having a very small area on the order of microns in order to confirm the principle of the two-dimensional photonic crystal. Therefore, a manufacturing method that can be mass-produced inexpensively with a large area has not been proposed.

  Then, this invention aims at providing the manufacturing method of the molded object which has a high regularity on the order of about 80 nm-1000 micrometers which can be used for an optical use, and is suitable for the optical use which can perform high light control. To do.

According to the present invention,
A method for producing a molded body having a phase separation structure comprising a matrix and a plurality of columnar structures that are regularly arranged in the matrix and have different refractive indexes from the matrix,
Disposing a photopolymerizable composition containing a photocurable monomer or oligomer and a photopolymerization initiator;
Disposing a photomask in which mask holes are regularly arranged between the disposed photopolymerizable composition and the light source;
In a state where a fly-eye lens is arranged between the light source and the photomask, the light source is irradiated with parallel light toward the arranged photopolymerizable composition to cure the photopolymerizable composition. Obtaining a molded body, comprising:
The light from the light source is irradiated to the photopolymerizable composition in a state where the intensity distribution derived from the single lens arrangement pattern of the fly-eye lens is neatly overlapped,
The manufacturing method of the molded object characterized by this is provided.

  According to such a configuration, there is provided a method for producing a molded article having high regularity on the order of about 80 nm to 1000 μm that can be used for optical applications and suitable for optical applications capable of advanced light control.

  According to another preferable aspect of the present invention, the arrangement rule of the mask holes of the photomask and the arrangement rule of the single lenses of the fly-eye lens are the same.

  According to another preferred aspect of the present invention, the arrangement rule of the mask holes of the photomask is different from the arrangement rule of the single lenses of the fly-eye lens.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the molded object suitable for the optical use which has high regularity on the order of about 80 nm-1000 micrometers which can be used for an optical use, and high light control is provided.

It is a perspective view which shows typically the structure of the molded object produced with the manufacturing method of preferable embodiment of this invention. It is a schematic drawing of the structure of the light irradiation apparatus used with the manufacturing method of the molded object of preferable embodiment of this invention. It is drawing for demonstrating a viewing angle (collimation half angle). It is drawing which shows typically light intensity distribution derived from the single lens arrangement pattern of a fly-eye lens. 6 is a diagram for explaining a problem to be solved by the conventional technology. It is drawing which shows the overlap of the light ray which passed the mask hole of the photomask which considered the light intensity distribution derived from a fly eye lens in the preferable aspect of this invention. It is drawing which shows the overlap of the light ray which passed the mask hole of the photomask which considered the light intensity distribution derived from a fly eye lens in the preferable aspect of this invention. It is drawing which shows the overlap of the light ray which passed the mask hole of the photomask which considered the light intensity distribution derived from a fly eye lens in the preferable aspect of this invention. It is drawing which shows the overlap of the light ray which passed the mask hole of the photomask which considered the light intensity distribution derived from a fly eye lens in the preferable aspect of this invention. It is typical drawing which shows the molded object from which a columnar structure becomes plate shape. It is drawing which shows the structure of the apparatus which performs the performance evaluation of a molded object. 4 is a graph showing the relationship between the incident angle and the minus first-order diffracted light intensity of the sample produced in Example 1. 4 is a graph showing a relationship between an incident angle of a sample produced in Example 2 and a minus first-order diffracted light intensity.

Hereinafter, the manufacturing method of the molded object of preferable embodiment of this invention is demonstrated. The manufacturing method of this embodiment is similar to the method of Patent Document 1, but is characterized by a light irradiation method of irradiating light to the photopolymerizable composition.
First, the structure of the molded object 1 produced with the manufacturing method of preferable embodiment of this invention is demonstrated. FIG. 1 is a perspective view schematically showing the configuration of the molded body 100.

The basic structure of the molded body 100 disclosed in Patent Document 1 and the like is the same. As shown in FIG. 1, the molded body 100 includes a thin plate-like matrix 101 and a matrix 101. It is comprised from the some columnar columnar structure 102 arrange | positioned.
The columnar structure 102 is oriented so that its axis extends in the thickness direction of the thin plate (film) shaped molded body 100, and regularly on the order of 80 nm to 1000 μm along the surface of the film shaped molded body. It is arranged.

  Further, the columnar structure 102 has a refractive index different from that of the matrix 101. Note that the refractive index continuously changes between the matrix 101 and the columnar structure 102.

  Next, the structure of the light irradiation apparatus used with the manufacturing method of the molded object of preferable embodiment of this invention is demonstrated. FIG. 2 is a schematic drawing of the configuration of a light irradiation device used in the method for producing a molded article according to a preferred embodiment of the present invention.

  The light irradiation device includes a lamp (ultra-high pressure mercury lamp) 1 that is a light source, a dichroic mirror 2 that reflects light from the light source, a fly-eye lens sheet 4 that transmits light reflected by the dichroic mirror 2, and a fly-eye lens. The sheet 4 and a concave mirror 8 that reflects the transmitted light toward the photopolymerizable composition 6 are provided. A photomask 10 is disposed between the concave mirror 8 and the photopolymerizable composition 6.

  In this light irradiation apparatus, a part of the light from the light source 1 is reflected by the dichroic mirror 2, passes through the fly-eye lens 4, then reflected by the concave mirror 8, and is arranged in a film shape via the photomask 10. The light-polymerizable composition 6 is incident from a direction perpendicular to the surface thereof.

  The light reaching the photomask 10 is quasi-parallel light having an angle distribution within a certain range, and the light passing through the pinhole (mask hole 12) has a viewing angle α (collimation half angle) derived from the light source. (Figure 3). The light transmitted through the fly-eye lens has a light intensity distribution derived from the single-lens arrangement pattern of the fly-eye lens. Therefore, when the fly-eye lens 4 is disposed on the light source 1 side as in the light irradiation device used in the present embodiment, light having a viewing angle that has passed through the pinhole (mask hole) is included in the viewing angle. This results in a light intensity distribution derived from the single lens arrangement pattern of the fly-eye lens.

  FIG. 4 is a drawing schematically showing this light intensity distribution, and light passing through the fly-eye lens 4 and passing through the mask hole 12 of the photomask 10 is indicated by a circle 16 on the projection surface 14. It shows having a strong portion derived from the single lens arrangement pattern of the fly-eye lens.

  As described above, in the method for manufacturing a molded article described in Patent Document 1, a photomask having a structure in which a large number of pinholes (mask holes) are regularly arranged is used. Since the light that has passed through the mask holes spreads based on the viewing angle, in the method for producing a molded article described in Patent Document 1, the light rays that are emitted from the adjacent mask holes 12 and 12 are made of the photopolymerizable composition 6. In order to prevent the surface from overlapping as shown in FIG. 5, the photomask 10 needs to be sufficiently close to the surface of the photopolymerizable composition 6.

In the method for manufacturing a molded body according to this embodiment, a photomask 10 having a configuration in which a large number of mask holes are regularly arranged is used, as described in Patent Document 1. The most different point of the manufacturing method of the present embodiment from the manufacturing method of Cited Document 1 is that light beams emitted from adjacent mask holes 12 are intentionally formed on the surface of the photopolymerizable composition 6 under predetermined conditions. (In other words, “clean”) It is to overlap.
Next, this point will be described.

As described above, when the fly-eye lens 4 is arranged on the light source 1 side as in the light irradiation device used in the present embodiment, the light having a viewing angle that has passed through the pinhole (mask hole) is the viewing angle. In this case, a light intensity distribution derived from the single lens arrangement pattern of the fly-eye lens is generated.
In the present embodiment, the photomask 10 and the like are arranged so that the intensity distribution of the light passing through the mask holes derived from the single lens arrangement pattern of the fly-eye lens is neatly overlapped on the photopolymerizable composition 6.

  Here, “the intensity distribution derived from the single-lens arrangement pattern of the fly-eye lens clearly overlaps on the photopolymerizable composition 6” means that the single-lens arrangement pattern of the fly-eye lens included in the light that has passed through the mask hole. It means that the high-intensity parts generated from the overlapping overlap.

Hereinafter, a state in which “the intensity distribution of the light passing through the mask hole derived from the single lens arrangement pattern of the fly-eye lens overlaps cleanly” will be described.
FIG. 6 is a cross-sectional view showing the overlap of light rays that have passed through the mask hole of the photomask, taking into account the light intensity distribution derived from the fly-eye lens. In FIG. 5, the portion of the light that passes through the mask hole and is applied to the photopolymerizable composition 6 that has increased in intensity due to the fly-eye lens is indicated by a solid line.

The position a in FIG. 6 is a region where the photopolymerizable composition has been arranged by the production method of Patent Document 1. On the other hand, in the present embodiment, the photopolymerizable composition is located at positions b, c, d, and e, which are positions where “the intensity distribution of the light passing through the mask hole derived from the single lens arrangement pattern of the fly-eye lens overlaps cleanly”. The photomask 10, the photopolymerizable composition 6, and the like are relatively disposed so that 6 is disposed.
From FIG. 6, it can be seen that the photomask 10 can be arranged away from the photopolymerizable composition 6 as compared with the method of Patent Document 1.

  At the position b, the high-strength portions located on the outermost sides of the adjacent mask holes 12 overlap each other, and on the photopolymerizable composition 6, the period is 1/4 of the arrangement period (interval) of the mask holes 12. A portion with high intensity is projected.

  Further, at the position c, the two high-strength portions on the outside of the adjacent mask holes 12 overlap each other, and on the photopolymerizable composition 6, the period is 1/3 of the arrangement period (interval) of the mask holes 12. A portion with high intensity is projected.

  Further, at the position d, the three high-strength portions of the adjacent mask holes 12 overlap each other, and on the photopolymerizable composition 6, the period is 1/4 of the arrangement period (interval) of the mask holes 12. A portion with high intensity is projected.

  Furthermore, at the position e, all the high portions of the adjacent mask holes 12 overlap each other, and the intensity is high on the photopolymerizable composition 6 with the same period as the arrangement period (interval) of the mask holes 12. Part is projected.

  As described above, by adjusting the interval between the photomask 10 and the photopolymerizable composition 6, a predetermined relationship (for example, 1 / n times :) with respect to the arrangement period (interval) of the mask holes of the photomask. However, n is an integer of 1 or more), and a portion having high strength can be imaged on the surface of the photopolymerizable composition 6.

FIG. 7 shows a case where n = 1, that is, the distance x between the mask holes 12 is equal to the distance between the portions of strong light on the surface of the photopolymerizable composition 6, and n = 2, ie, the distance x between the mask holes 12 is photopolymerizable. FIG. 8 shows a case where the distance between the strong light portions on the surface of the composition 6 is twice, and n = 3, that is, the distance x between the mask holes 12 is that of the strong light on the surface of the photopolymerizable composition 6. FIG. 9 shows the case where the interval is three times the interval.
7, 8, and 9 shown here are cross-sectional views when the fly-eye lens is a square lattice and is an aggregate of a total of 25 single lenses, 5 in each of the vertical and horizontal directions. As long as n is 1 or more, any integer is applicable to the manufacturing method of this embodiment.

  The pattern formed by the fly-eye lens and the photomask imaged on the surface of the photopolymerizable composition 6 has a composition ratio, a crosslinking density or a polymerization degree near the surface of the photopolymerizable composition (light source side surface) due to the difference in brightness. Make a difference. That is, the reaction proceeds preferentially in the bright part, and the refractive index rises more than in the dark part. Then, light is collected in a bright part having a high refractive index to be a waveguide mode, and the columnar structure is grown in a direction perpendicularly penetrating the surface, thereby forming a columnar structure.

  Further, when n is increased in order to form a finer periodic structure, the number of single lenses that form a fly-eye lens may be increased. When the number of single lenses forming the fly-eye lens is small, the number of n increases (to reduce the pattern more finely), and this is summarized at each point imaged on the surface of the photopolymerizable composition 6. Variation in the number of light rays (the number of high intensity portions, ie, the number of solid lines in FIG. 6), the light intensity at each point imaged on the surface of the photopolymerizable composition 6 is different. This is because the refractive index varies.

  For example, when the fly-eye lens is a square lattice and is an aggregate of 25 single lenses in total of 5 in each of the vertical and horizontal directions, the number of rays collected at each point is uniform at 25 when n = 1, but n The number of rays gathered at each point varies from 4 to 9 in the case of = 2 and 1 to 4 in the case of n = 3.

  Therefore, when the fly-eye lens is a square lattice and is an aggregate of a total of 49 single lenses of 7 in each of the vertical and horizontal directions, when n = 1, 49 light beams are uniformly accumulated at each point, and n = 2. 9 to 16 in the case, 4 to 9 in the case of n = 3, and the variation in the number of rays gathered at each point is more varied than the case of a total of 25 single lenses of 5 in each direction. Will improve.

Further, the smaller the viewing angle derived from the light irradiation device, the larger the distance between the photomask 10 and the surface of the photopolymerizable composition 6 in the manufacturing method of the present embodiment.
Furthermore, even when the wavelength of the irradiated light is shorter, the diameter of the mask hole 12 of the photomask 10 is reduced, the manufacturing method of this embodiment can be used.

  In this way, by using a combination of a fly-eye lens pattern and a photomask pattern, a molded body in which columnar structures are arranged with a shorter period than a conventional method of manufacturing a molded body using a photomask is formed. It becomes possible. Conventionally, the distance between the photomask and the photopolymerizable composition has been reduced in order to reach the photopolymerizable composition before the light transmitted through the holes of the photomask spreads according to the viewing angle. This is because the distance between the photomask and the photopolymerizable composition can be increased as compared with the conventional method.

In addition, the molded article produced by the production method of the present invention has not only a fine two-dimensional regular structure, but also a columnar structure with a very high aspect ratio in a direction perpendicular to the plane.
With this high aspect ratio structure, even if the difference in refractive index between the columnar structure and the matrix is small, advanced light control is possible.

Next, the arrangement pattern of the mask holes 12 of the photomask 10 and the single lens arrangement pattern of the fly-eye lens 4 will be described.
When the pattern of the mask hole 12 and the pattern of the fly eye lens are the same, the pattern formed in the molded body is the same as that of the photomask and the fly eye lens.

  Further, when the single lens arrangement pattern of the fly-eye lens 4 is different from the pattern of the mask hole 12, for example, the single lens arrangement pattern of the fly-eye lens 4 is a square lattice, and the pattern of the mask hole 12 is a triangular lattice. In this case, when the distance between the photomask 10 and the surface of the photopolymerizable composition 6 is controlled, the cross-sectional shape of the columnar structure is not a circle, and a plurality of columns are connected in one direction to form a plate shape. In this case, when observed from a direction perpendicular to the surface, a molded body 100 ′ having a structure in which plate-like columnar structures 102 ′ are arranged in a striped pattern in the matrix 101 ′ (FIG. 10).

  When using these methods capable of forming a stripe pattern, 1 / n (n is an integer of 1 or more) in consideration of the regular arrangement pitch in the single lens arrangement pattern of the fly-eye lens and the regular arrangement pitch of the photomask pattern. A striped regular structure can be formed at a pitch.

  As described above, when the single lens arrangement pattern of the fly-eye lens 4 is different from the pattern of the mask hole 12, the arrangement pattern of the columnar structures is different from the single lens arrangement pattern of the fly-eye lens 4 and the pattern of the mask hole 12. A molded body can be produced.

Next, the detail of the light irradiation apparatus used for the manufacturing method of preferable embodiment of this invention is demonstrated.
(Light source and optical system)
The type of the light source lamp 1 used in the light irradiation device is appropriately selected depending on the wavelength band to be used. Specific examples of the lamp 1 include, for example, a high pressure UV lamp, an ultra high pressure UV lamp, a low pressure UV lamp, a deep UV lamp, a xenon flash lamp, a xenon short arc lamp, an excimer lamp, a metal halide lamp, a rare gas fluorescent lamp, a halogen heater lamp, A halogen lamp etc. are mentioned.

  A band pass filter or the like may be used to limit the wavelength to be used. It is preferable to arrange the dichroic mirror 2 on the downstream side of the light source so that the heat rays do not reach the photopolymerizable composition 6.

As described above, the fly-eye lens 4 can form a finer periodic structure as the number of single lenses increases. When the single lenses are arranged in a square lattice, the number of single lenses included in the fly-eye lens 4 is a total of 25 or more in the vertical and horizontal directions, and a total of 19 or more in the case of being arranged in a triangular lattice. It is preferable to use a single lens assembly.
Furthermore, the shape of the single lens used for the fly-eye lens 4 is not particularly limited, and various lenses such as a cylindrical lens and a Fresnel lens can be used.

  The viewing angle of light reaching the photopolymerizable composition 6 is determined by the configuration of the entire light irradiation apparatus, but the viewing angle determines the distance from the photomask to the photopolymerizable composition. In order to increase the distance of the composition 6, it is desirable to configure the light irradiation device so that the viewing angle is reduced. Specifically, the viewing angle on the surface of the photopolymerizable composition 6 is preferably 3.0 degrees or less, more preferably 1.5 degrees or less, and further preferably 1.0 degrees or less.

(Photomask)
As the photomask 10, those used in the photolithography method can be used. The pattern of the mask holes 12, the size of the hole diameter, the pitch, and the shape are not particularly limited. The shape of the mask hole may be a polygon such as a circle, a triangle, a quadrangle, a hexagon, and an octagon. When the mask hole 12 is circular, the hole diameter is preferably 40 nm to 500 μm, more preferably 100 nm to 10 μm, and the pitch is preferably 80 nm to 1000 μm, more preferably 200 nm to 20 μm. Moreover, the diameter of the mask hole 12 with respect to a pitch is not specifically limited.

  Hereafter, the photopolymerizable composition used for the manufacturing method of preferable embodiment of this invention is demonstrated.

(Polyfunctional monomer)
It is preferable that a polyfunctional monomer is contained in the photopolymerizable composition. As such a polyfunctional monomer, a (meth) acryl monomer containing a (meth) acryloyl group, a monomer containing a vinyl group, an allyl group, or the like is particularly preferable.

  Specific examples of the polyfunctional monomer include triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6 -Hexanediol di (meth) acrylate, hydrogenated dicyclopentadienyl di (meth) acrylate, ethylene oxide modified bisphenol A di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, Tetramethylolmethane tetra (meth) acrylate, pentaerythritol hexa (meth) acrylate, polyfunctional epoxy (meth) acrylate, polyfunctional urethane (meth) acrylate, divinylbenzene, toluene Examples include allyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl chlorendate, N, N′-m-phenylenebismaleimide, diallyl phthalate, and the like. These are used alone or as a mixture of two or more. can do.

  A polyfunctional monomer having three or more polymerizable carbon-carbon double bonds in the molecule is preferable because the density of the crosslink density due to the difference in the degree of polymerization is likely to increase and a columnar structure is easily formed.

  Particularly preferred polyfunctional monomers having three or more polymerizable carbon-carbon double bonds are trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, penta There is erythritol hexa (meth) acrylate.

  When two or more kinds of polyfunctional monomers or oligomers thereof are used as the photopolymerizable composition, it is preferable to use those having different refractive indexes when the respective homopolymers are used. It is more preferable to combine large ones.

  In order to obtain a high diffraction efficiency with the optical low-pass filter 1, it is necessary to increase the refractive index difference between the matrix and the columnar structure. Further, since the difference in refractive index is increased by the diffusion of the monomer during the polymerization process, a combination having a large difference in diffusion constant is preferable.

  In addition, when using 3 or more types of polyfunctional monomers or oligomers, the refractive index difference between at least any two of the respective homopolymers may be within the above range. Further, the two monomers or oligomers having the largest refractive index difference of the homopolymer are preferably used in a weight ratio of 10:90 to 90:10 in order to obtain high diffraction efficiency.

(Monofunctional monomer)
In the photopolymerizable composition, a monofunctional monomer or oligomer having one polymerizable carbon-carbon double bond in the molecule may be used together with the polyfunctional monomer or oligomer as described above. As such a monofunctional monomer or oligomer, those containing a (meth) acryl monomer containing a (meth) acryloyl group, a vinyl group, an allyl group or the like are particularly preferable.

  Specific examples of the monofunctional monomer include, for example, methyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, ethyl carbitol (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, isobornyl (meth) acrylate, phenyl Carbitol (meth) acrylate, nonylphenoxyethyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, (meth) acryloyloxyethyl succinate, (meth) acryloyloxyethyl phthalate, phenyl (meth) acrylate , Cyanoethyl (meth) acrylate, Tribromophenyl (meth) acrylate, Phenoxyethyl (meth) acrylate, Tribromophenoxyethyl (meth) acrylate, Ben (Meth) acrylate, p-bromobenzyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) ) (Meth) acrylate compounds such as acrylate; vinyl compounds such as styrene, p-chlorostyrene, vinyl acetate, acrylonitrile, N-vinyl pyrrolidone, vinyl naphthalene; allyl compounds such as ethylene glycol bisallyl carbonate, diallyl phthalate, diallyl isophthalate Etc.

  These monofunctional monomers or oligomers are used for imparting flexibility to the optical low-pass filter 1, and the amount used is preferably in the range of 10 to 99% by mass of the total amount with the polyfunctional monomers or oligomers. A range of 50% by mass is more preferred.

(Polymer, low molecular weight compound)
The photopolymerizable composition may also be a homogeneous solution mixture containing the polyfunctional monomer or oligomer and a compound having no polymerizable carbon-carbon double bond.
Examples of the compound having no polymerizable carbon-carbon double bond include polymers such as polystyrene, polymethyl methacrylate, polyethylene oxide, polyvinyl pyrrolidone, polyvinyl alcohol, and nylon, toluene, n-hexane, cyclohexane, acetone, and methyl ethyl ketone. , Low molecular weight compounds such as methyl alcohol, ethyl alcohol, ethyl acetate, acetonitrile, dimethylacetamide, dimethylformamide, and tetrahydrofuran, organic halogen compounds, organosilicon compounds, plasticizers, additives such as stabilizers, and the like.

  These compounds having no polymerizable carbon-carbon double bond are used for adjusting the viscosity of the photopolymerizable composition to improve the handleability when the optical low-pass filter 1 is produced, and in the photopolymerizable composition. It is used to improve the curability by reducing the monomer component ratio, and the amount used is preferably in the range of 1 to 99% by mass of the total amount with the polyfunctional monomer or oligomer, and the handling property is also improved. However, in order to form a columnar structure having a regular arrangement, the range of 1 to 50% by mass is more preferable.

(Initiator)
The photopolymerization initiator used in the photopolymerizable composition is not particularly limited as long as it is used in normal photopolymerization in which polymerization is performed by irradiating active energy rays such as ultraviolet rays. For example, benzophenone , Benzyl, Michler's ketone, 2-chlorothioxanthone, benzoin ethyl ether, diethoxyacetophenone, pt-butyltrichloroacetophenone, benzyldimethyl ketal, 2-hydroxy-2-methylpropylphenone, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl -2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, dibenzosuberone and the like.

  The use amount of these photopolymerization initiators is preferably in the range of 0.001 to 10% by mass with respect to the weight of the other photopolymerizable composition so as not to deteriorate the transparency of the optical low-pass filter 1. Therefore, the content is more preferably 0.01 to 5% by mass.

The molded object manufacturing method of this embodiment is implemented using the light irradiation apparatus and raw material which were mentioned above.
Specifically, first, a photopolymerizable composition containing a photocurable monomer or oligomer and a photopolymerization initiator is arranged in a thin film by being injected into a mold or applied to a substrate, and arranged. Between the photopolymerizable composition 6 and the light source 1, a photomask in which the mask holes 12 are regularly arranged is arranged. And in the state which has arrange | positioned the fly eye lens 4 between the light source 1 and the photomask 12, parallel light from the light source 1 is irradiated toward the arrange | positioned photopolymerizable composition 6, and a photopolymerizable composition is hardened | cured. The molded body 100 is obtained.
In addition, the light from a light source is irradiated to a photopolymerizable composition in the state where the intensity distribution derived from the single lens arrangement pattern of a fly-eye lens as illustrated in FIG.
In addition, the irradiation time of light etc. are the same as that of the well-known molded object manufacturing method described in patent document 1 grade | etc.,.

The photomask is arranged by separating a gap (air layer) having a predetermined thickness from a photopolymerizable composition arranged in a thin film by injection into a mold or application to a substrate. As a method for arranging the photomask, any method may be used as long as the positional relationship between the photomask and the photopolymerizable composition such as the thickness of the gap layer is accurately maintained.
As a modified example, in a configuration in which the photopolymerizable composition is sandwiched between glass plates and irradiated with parallel light to cure the resin, by adjusting the thickness of the glass plate, the photopolymerizable composition and the photomask are adjusted. The distance may be adjusted.

Hereinafter, the optical performance of the molded body 100 produced by the production method of the preferred embodiment of the present invention will be described.
Since the molded body has columnar structures arranged with high regularity, a clear diffraction spot can be observed when monochromatic light having high straightness such as laser light is incident.

  And since the molded object 100 has a columnar structure with a high aspect ratio, it has the property as a Bragg diffraction grating. Therefore, the molded body 100 is characterized in that when laser light is incident, 0th-order and 1st-order diffracted light is generated, and second-order and subsequent multi-order diffracted light is hardly generated.

Further, since the molded body 100 is a Bragg diffraction grating, it tends to generate strong first-order diffracted light at a specific incident angle, and generates strong diffracted light at the incident angle of Equation (1), which is the Bragg diffraction condition.
2nΛ · sinθ = mλ Equation (1)
n is a refractive index, Λ is a regular period of the diffraction grating, θ is an incident angle, m is a diffraction order, and λ is a wavelength of incident light.

  The incident angle dependency of the diffracted light intensity becomes more prominent as the columnar structure aspect ratio is higher and the regular period of arrangement is smaller. As can be seen from the equation (1), the incident angle at which the diffracted light intensity becomes maximum increases as the regular period in which the columnar structures are arranged decreases. Further, when the regular period in which the columnar structures are arranged to a certain region or more is reduced, light guided in the plane of the molded body 100 is emitted in a direction nearly perpendicular to the plane. This can be said to be a phenomenon in which the light beam guided in the plane of the molded body 100 is diffracted by the Bragg diffraction grating and emitted from the plane. This is because the molded body 100 has a feature as a two-dimensional photonic crystal, and light guided in the plane of the molded body 100 cannot exist due to the photonic band gap, and is emitted to the outside of the molded body 100. In other words.

  Such a phenomenon is generally considered to occur in a region where the regular period of the structure of the molded body 100 is close to the wavelength of light.

  Such optical properties of the molded body 100 can be used for light-emitting elements that require advanced light control. Specifically, for example, it can be used to improve the light emission extraction efficiency of a light emitting element such as an organic electroluminescence element or a light emitting diode element, or a wavelength conversion film using a light emitting dye. This is because the structure of the molded body 100 is a structure that prevents light from being guided in the plane, so that the molded body 100 is molded into various layers existing between the light emitting part or the light emitting part and the outside of the light emitting element. If the body 100 is applied, the light emission extraction efficiency is improved.

(Optical property evaluation)
Since the molded body 100 has the properties of a Bragg diffraction grating as described above, it is confirmed whether or not the molded body 100 having the desired regular period can be manufactured by making a laser incident on the molded body 100 and checking the first-order diffracted light. Is possible. Therefore, laser light was incident on the molded body 100 and the first-order diffracted light was observed. The incident angle when the laser light is incident on the molded body 100 is gradually changed, and a photodiode is installed at an angle at which the −1st order diffracted light derived from the Bragg diffraction condition appears, and the −1st order diffracted light intensity is continuously increased. Observe at. FIG. 11 shows a schematic configuration of an apparatus used for evaluation.

  The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention.

Hereinafter, the present invention will be specifically described by way of examples.
Example 1
In Example 1, 40 parts by mass of benzyl acrylate (manufactured by Osaka Organic Chemical Co., Ltd.), 30 parts by mass of ethoxylated polypropylene glycol dimethacrylate (trade name: 1206PE, manufactured by Shin-Nakamura Chemical Co., Ltd.), polyfunctional urethane acrylate ( In a mixture consisting of product name: U-2PPA (manufactured by Shin-Nakamura Chemical Co., Ltd.), 1.0 part by mass of 1-hydroxycyclohexyl phenyl ketone (product name: IRGACURE 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) is dissolved and light is dissolved. A polymerizable composition was obtained.

The obtained photopolymerizable composition was coated on a 100 mm square and 0.5 mm thick glass substrate using a bar coater. As the bar coater, wire No. 40 (manufactured by Tester Sangyo Co., Ltd.) was used. Next, a photomask in which 1.0 μm square light passage areas were arranged in a triangular lattice pattern at a pitch of 2.0 μm was arranged so that the distance between the photopolymerizable composition and the photomask was 135 μm. From the upper direction of the photomask, ultraviolet parallel light was irradiated at 1200 mJ / cm ² using a parallel light irradiator in which fly-eye lenses were arranged in a triangular lattice. Thereafter, the photomask was removed, and the photopolymerizable composition was polymerized and cured by irradiation with 1200 mJ / cm ² ultraviolet parallel light to obtain a molded body.

  The obtained molded body had a thickness of 60 μm, and when observed with a transmission optical microscope, it was confirmed that the columnar structures were arranged in a triangular lattice shape. When a green laser beam having a wavelength of 532 nm was incident on the molded body, the intensity of the −1st order diffracted light reached a maximum at an incident angle of 15.4 degrees. Therefore, when the regular period of the Bragg diffraction grating when the incident angle satisfying the Bragg conditional expression is 15.4 degrees is calculated, it is 1.00 μm, and the Bragg has a regular period that is 1/2 of the regular period of the photomask. It was found that a diffraction grating could be produced. FIG. 12 shows the relationship between the incident angle and the minus first-order diffracted light intensity of the sample produced in Example 1.

(Example 2)
In Example 2, the same photopolymerizable composition as in Example 1 was used, and only the pattern of the photomask and the distance between the photomask and the surface of the photopolymerizable composition were changed. A molded body was produced using an apparatus.
As the photomask, a 2.0 μm square light passing region was arranged in a triangular lattice pattern with a pitch of 4.0 μm, and the photopolymerizable composition and the photomask were arranged so that the distance was 270 μm.

  The obtained molded body had a thickness of 60 μm, and when observed with a transmission optical microscope, it was confirmed that the columnar structures were arranged in a triangular lattice shape. When a green laser beam having a wavelength of 532 nm was incident on the molded body, the intensity of the −1st order diffracted light reached a maximum at an incident angle of 7.4 degrees. Therefore, the Bragg diffraction grating regular period when the incident angle satisfying the Bragg conditional expression is 7.4 degrees is calculated to be 2.06 μm, which is a Bragg having a regular period that is 1/2 of the regular period of the photomask. It was found that a diffraction grating could be produced. FIG. 13 shows the relationship between the incident angle and the minus first-order diffracted light intensity of the sample produced in Example 2.

(Example 3)
In Example 3, the same photopolymerizable composition as in Example 1 was used, and only the pattern of the photomask and the distance between the photomask and the surface of the photopolymerizable composition were changed. A molded body was produced using an apparatus.

A photomask having a square light passage area of 2.0 μm square arranged in a square lattice at a pitch of 5.0 μm was used, and the photopolymerizable composition surface and the photomask were arranged so that the distance between them was 290 μm.
The obtained molded body had a thickness of 60 μm, and it was confirmed that the plate-like columnar structures were arranged in a striped pattern when observed from a direction perpendicular to the surface with a transmission optical microscope.

Example 4
In Example 4, the same photopolymerizable composition as in Example 1 was used, and the photomask pattern, the distance between the photomask and the photopolymerizable composition, and the fly-eye lens pattern were changed. A molded body was produced in the same manner as described above.
A photomask having a square light passing area of 2.0 μm square arranged in a square lattice at a pitch of 5.0 μm was used, and the photopolymerizable composition surface and the photomask were arranged so that the distance between them was 235 μm. As the fly-eye lens, single lenses arranged in a square lattice shape were used.

  The obtained molded body had a thickness of 60 μm and was observed with a transmission optical microscope. As a result, columnar structures were arranged in a square lattice pattern at a pitch of 2.5 μm, which was 1/2 of the regular period of the photomask. It was confirmed that a pitch compact was produced.

(Comparative Example 1)
In Comparative Example 1, an experiment was performed by changing only the distance between the photopolymerizable composition surface and the photomask, as compared with Example 4.
The distance between the photomask and the surface of the photopolymerizable composition was 200 μm, and the 35 μm photomask was brought closer to that of Example 4. The obtained molded body had a thickness of 60 μm and was observed with a transmission optical microscope. As a result, columnar structures were arranged in a square lattice at a pitch of 5.0 μm, and the pitch was 1/2 of the pitch of the photomask. The molded product could not be produced.

100: Molded body 101: Matrix 102: Columnar structure

Claims (3)

A method for producing a molded body having a phase separation structure comprising a matrix and a plurality of columnar structures that are regularly arranged in the matrix and have different refractive indexes from the matrix,
Disposing a photopolymerizable composition containing a photocurable monomer or oligomer and a photopolymerization initiator;
Disposing a photomask in which mask holes are regularly arranged between the disposed photopolymerizable composition and the light source;
In a state where a fly-eye lens is arranged between the light source and the photomask, the light source is irradiated with parallel light toward the arranged photopolymerizable composition to cure the photopolymerizable composition. Obtaining a molded body, comprising:
The light from the light source is irradiated to the photopolymerizable composition in a state where the intensity distribution derived from the single lens arrangement pattern of the fly-eye lens is neatly overlapped,
The manufacturing method of the molded object characterized by this. The arrangement rule of the mask hole of the photomask is coincident with the arrangement rule of the single lens of the fly eye lens,
The manufacturing method of the molded object of Claim 1. The arrangement rule of the mask hole of the photomask is different from the arrangement rule of the single lens of the fly eye lens,
The manufacturing method of the molded object of Claim 1.

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