JP2009157251A - Manufacturing apparatus for light control film, and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for manufacturing a light control film with high productivity, the film which scatters only the light incident at a specified angle and having angle dependence for the haze value. <P>SOLUTION: A light source lamp 3 is disposed away from a resin composition film so as to allow the axial direction of the light source lamp 3 to intersect the moving direction of the resin composition film. A reflecting member 4, reflects the light from the light source lamp 3 for producing parallel beams, with which the resin composition film is irradiated. A light control film is formed, by having the resin composition film irradiated with a light from the light source lamp 3 to make it cure, while making the resin composition film move. Here, it is preferable that the angle dependence in a haze value of the photocuring film be produced, a light-shielding plate 5 having an opening 51 be placed in between the resin composition film and the light source lamp 3 so as to face the resin composition film. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a device for manufacturing a light control film and a method for manufacturing the same, and more particularly to a device for manufacturing a light control film having an angle dependency on the haze and a method for manufacturing the same.

  Conventionally, as a method for producing a light control film having a sufficient total light transmittance, a smooth surface and an angle dependency on the haze, at least two kinds of photopolymerizable monomers or oligomers having different refractive indexes The photo-curable resin composition containing is formed into a film shape, and the light control film is formed by irradiating light at a predetermined angle from a linear light source while relatively moving the molded photo-curable resin composition film. A forming method has been proposed (see, for example, Patent Document 1). FIG. 7 shows a conventional photocured film manufacturing apparatus.

The manufacturing apparatus of FIG. 7 includes a conveyor 1 that rotates clockwise, a linear light source lamp 3 that is disposed above the conveyor 1, and a light shield that is disposed directly above the conveyor 1 so as to be opposed to the conveyor 1. And a plate 5. The light shielding plate 5 is formed with a rectangular opening 51 having a predetermined width extending in a direction perpendicular to the moving direction of the conveyor 1. In such a manufacturing apparatus, when the glass substrate 2 on which the photocurable resin composition film was formed was placed on the conveyor 1 and moved, it was adjusted to a predetermined irradiation angle by the opening 51 of the light shielding plate 5. The light from the light source lamp 3 is sequentially irradiated onto the photocurable resin composition film. As a result, a photocured film that scatters only incident light from a specific angle and has an angle dependency on the haze value is produced.
Japanese Unexamined Patent Publication No. 2-67501

  However, the proposed technique has a problem in that when the relative movement speed of the photocurable resin composition film is increased, the light irradiation amount is insufficient and a desired haze value cannot be obtained. For this reason, it has been difficult to increase the productivity of the photocured film with the conventional manufacturing apparatus.

  The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a manufacturing apparatus and a manufacturing method capable of manufacturing a light control film having an angle dependency on the haze with high productivity. It is in.

  Another object of the present invention is to provide a manufacturing apparatus and a manufacturing method that can be manufactured uniformly and continuously even if the light control film has a large area.

  As a result of various studies to achieve the above object, the present inventor made the present invention based on the idea that light emitted from a linear light source may be efficiently irradiated onto a photocurable resin composition film. It came. That is, the light control film manufacturing apparatus according to the present invention arranges a linear light source so as to be opposed to a photocurable resin composition film (hereinafter sometimes referred to as “resin composition film”), A manufacturing apparatus for forming a light control film by irradiating light from a linear light source and curing the photocurable resin composition film while moving at least one of the curable resin composition film and the linear light source, The axial direction of the linear light source intersects with the moving direction, and a reflecting member is provided that reflects light from the linear light source into parallel light and irradiates the photocurable resin composition film. And

  Here, from the viewpoint of increasing the angle dependency of the haze value of the photocured film to be produced, between the photocurable resin composition film and the linear light source, so as to face the photocurable resin composition film, It is preferable to provide a plate-shaped light shielding member having an opening.

  As the photocurable resin composition, there are at least two types of photopolymerizable monomers each having a polymerizable carbon-carbon bond in the molecule and having a difference in the refractive index of the homopolymer obtained by homopolymerization. Or the thing containing an oligomer is suitable.

  Further, according to the present invention, at least two kinds of photopolymerizable monomers each having a polymerizable carbon-carbon bond in the molecule and having a difference in refractive index of a homopolymer obtained by homopolymerization or There is provided a method for producing a light control film in which a photocurable resin composition containing an oligomer is formed into a film and the resin composition film is cured using the production apparatus described above.

  The film thickness of the photocurable resin composition film is preferably 25 μm or more.

  According to the manufacturing apparatus and the manufacturing method of the present invention, a photocured film that scatters only incident light from a specific angle and has an angle dependency on the haze can be manufactured with high productivity. Further, even a large-area photocured film can be manufactured continuously and uniformly.

  Hereinafter, although the manufacturing apparatus and manufacturing method which concern on this invention are demonstrated based on figures, this invention is not limited to these embodiments at all.

  FIG. 1 is a perspective view showing an embodiment of a manufacturing apparatus according to the present invention. In addition, the same code | symbol is attached | subjected to the same member and part as FIG. 1 includes a conveyor 1 that rotates and moves in the direction of an arrow, a bar-like light source lamp (linear light source) 3 that is disposed above the conveyor 1 in a direction substantially orthogonal to the moving direction of the conveyor 1, and a conveyor. 1 is provided with a light shielding plate (light shielding member) 5 having a square-shaped opening 51 installed so as to face the conveyor 1. The light shielding plate 5 defines the light irradiation start angle and the light irradiation end angle by the opening 51 and prevents light from entering from outside the apparatus and hitting the resin composition film. Even when the light shielding plate 5 is not attached, the effect of the present invention can be obtained, but it is preferable to provide the light shielding plate 5 in order to obtain a sharp and high peak in the haze curve.

  On the opposite side of the light source lamp 3 from the conveyor side, a reflector 4 is attached. As shown in FIG. 2, the reflecting plate 4 reflects light from the light source lamp 3 into parallel light, and its cross-sectional shape is a paraboloid.

  In such a manufacturing apparatus, a glass substrate 2 having a resin composition film (not shown) formed on the surface thereof is placed on the conveyor 1 and moved at a predetermined speed, while the light from the light source lamp 3 is emitted from the resin composition. Irradiate the film. At this time, a part of the light emitted from the light source lamp 3 to the resin composition film side is absorbed and reflected by the light shielding plate 5, and the remaining light passes through the opening 15 to form the resin composition. Hit the material film. On the other hand, the light emitted to the side opposite to the resin composition film is reflected by the reflection plate to become parallel light, and almost all of the light passes through the opening 51 of the light shielding plate 5 and strikes the resin composition film. As a result, the amount of light applied to the resin composition film is larger than that of the conventional apparatus, and even if the moving speed of the resin composition film is increased, the amount of light necessary for curing the resin composition is irradiated. Become. Moreover, since a lot of light irradiates the resin composition film at almost the same irradiation angle, the peak of the haze value curve of the obtained photocured film in the same direction as the moving direction of the conveyor 1 becomes sharp. In addition, substantially parallel and substantially vertical directions mean that a range of about ± 10 ° is allowed.

  In order to adjust the light scattering angle region of the light control film in the same direction as the moving direction of the conveyor 1 and exhibiting a haze value of a predetermined value or more, the light irradiation angle with respect to the resin composition film may be adjusted. That is, while the reflecting plate 4 is swung in the circumferential direction of the light source lamp 3 and the position of the opening 51 of the light shielding plate 5 and the position of the light source lamp 3 are relatively moved, What is necessary is just to adjust a light irradiation angle. In addition, since the irradiation light with respect to the resin composition film | membrane in the orthogonal | vertical direction with respect to the moving direction of the conveyor 1 hits a resin composition film | membrane in the wide angle range from the opening part 51 of the light shielding board 5, the conveyor 1 of a photocuring film | membrane. The haze value in the direction perpendicular to the moving direction is not angularly dependent and shows a high value over the entire angular range.

  The reflector 4 used in the present invention is not particularly limited as long as the reflected light is converted into parallel light, and a conventionally known one such as a concave mirror can be used.

  The light source lamp 3 used in the present invention emits ultraviolet light or other light that contributes to the photopolymerization of the resin composition, and the light source has a linear shape when viewed from the irradiated position (the surface of the resin composition film). It is what has made. Using a rotating mirror and a concave mirror to make the light source appear to be linear when viewed from the irradiated position, for example, a series of many point light sources arranged linearly, or light from laser light, etc. Thus, an apparatus that scans (irradiates from one of the irradiated positions from a number of different angles) can also be used as the linear light source of the present invention.

  When the irradiation light is ultraviolet rays, the linear ultraviolet lamp is not particularly limited as long as it generates ultraviolet rays, but a mercury lamp or a metal halide lamp is usually preferable in consideration of ease of handling.

  The material of the light shielding plate 5 is not particularly limited, and glass, ceramics, metal, plastic and the like can be used. However, the light shielding plate 5 is durable against strong light and heat from the light source lamp 3 and has physical strength. Stronger is preferable. Specifically, metals and alloys such as SUS, iron, and aluminum, and heat resistant polymer materials are preferably used. However, it is preferable to apply black coating, perform blackening treatment of metal, or perform electrostatic flocking so that light is not reflected as much as possible.

  In the manufacturing apparatus of the embodiment, the light source lamp 3 is fixed and the resin composition film formed on the glass substrate 2 is moved by the conveyor 1. However, the resin composition film is fixed and the light source lamp 3 is fixed. It may be moved, or both the resin composition film and the light source lamp 3 may be moved. However, in order to continuously photo-cure the belt-shaped resin composition film, it is preferable to fix the light source lamp 3 and move the resin composition film. The relative movement speed between the resin composition film and the light source lamp 3 is usually preferably in the range of 0.01 to 10.0 m / min, more preferably in the range of 0.1 to 5.0 m / min.

  The resin composition film is formed by coating the resin composition on a substrate such as a glass plate or a polyethylene terephthalate plate, or encapsulating the resin composition in a cell as in the above embodiment. do it. The substrate may be a single wafer or a continuous film. The film thickness of the resin composition film must be thick to some extent, and at least 25 μm is necessary. The preferable film thickness of the resin composition film is 100 μm or more, and more preferably 200 μm or more.

  The photocurable resin composition used in the present invention has at least two types of photopolymerization having a polymerizable carbon-carbon bond in each molecule and a difference in refractive index of homopolymers obtained by homopolymerization. Compositions containing possible monomers or oligomers are preferred. Here, the polymerizable carbon-carbon bond means a carbon-carbon double bond capable of addition polymerization or a carbon-carbon triple bond capable of addition polymerization. Specifically, for example, vinyl group, allyl group, styryl group, acryloyl group, methacryloyl group, acrylamide group, trans-1-oxo-2-butenoxy group, cinnamoyl group, butadiene structure, polymerizable conjugate bond, cyclopentene ring structure And the like, and the like. Among these, an acryloyl group and a methacryloyl group are preferable, and an acryloyl group is particularly preferable.

  Examples of the photopolymerizable monomer include tetrahydrofurfuryl acrylate, ethyl carbitol acrylate, dicyclopentenyloxyethyl acrylate, phenyl carbitol acrylate, nonylphenoxyethyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, and ω-hydroxy. Hexanoyloxyethyl acrylate, acryloyloxyethyl succinate, acryloyloxyethyl phthalate, isobornyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, 2,2,3,3-tetrafluoropropyl acrylate, phenyl carbitol acrylate, nonyl phenoxy Ethyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2,4,6-to Bromphenoxyethyl acrylate, 2,4,6-tribromophenyl acrylate, N-vinylpyrrolidone, N-acryloylmorpholine, 2-phenylphenyl acrylate, p-cumylphenyl acrylate, diphenylmethyl acrylate, 3-phenoxyphenyl acrylate And compounds having one polymerizable carbon-carbon double bond in the molecule, such as a methacrylate monomer corresponding to the acrylate.

  Also, for example, triethylene glycol diacrylate, polyethylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, hydrogenated dicyclopentadienyl diacrylate, trimethylolpropane triacrylate, pentaerythritol hexaacrylate , Ethylene oxide modified bisphenol A diacrylate, trisacryloxy isocyanurate, polyfunctional epoxy acrylate, polyfunctional urethane acrylate, methacrylates corresponding to these acrylates such as diethylene glycol bisallyl carbonate, divinylbenzene, triallyl isocyanurate, etc. Also included are compounds having a plurality of polymerizable carbon-carbon double bonds in the molecule.

  As the photopolymerizable oligomer, for example, polyester acrylate, polyol polyacrylate, modified polyol polyacrylate, isocyanuric acid skeleton polyacrylate, melamine acrylate, hydantoin skeleton polyacrylate, polybutadiene acrylate, epoxy acrylate, urethane acrylate, etc. Examples thereof include acrylates and methacrylates corresponding to these acrylates. As a urethane acrylate oligomer, what is produced | generated by addition reaction of polyisocyanate, a polyol, and 2-hydroxyalkyl (meth) acrylate is illustrated. Here, examples of the polyisocyanate include toluene diisocyanate, isophorone diisocyanate, trimethylhexamethylene diisocyanate, and hexamethylene diisocyanate. Examples of the polyol include polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

  Here, the monomer or oligomer to be used is selected from those having a difference in refractive index of homopolymers obtained by homopolymerization. An area that scatters light, that is, a light scattering angle area, is formed by irradiating and curing light from a predetermined direction on a composition in which at least two kinds of photopolymerizable monomers or oligomers having different refractive indexes are mixed. The This composition expresses the angle dependency of the haze value due to the mutual solubility of each of a plurality of composing compounds and the difference in the respective refractive indexes. When the reaction rate is different, the degree of light scattering, that is, the haze value increases. This difference in refractive index is usually preferably 0.01 or more, and particularly preferably 0.02 or more.

  The photocurable resin composition used in the present invention may contain three or more monomers or oligomers having a polymerizable carbon-carbon bond in the molecule, and in that case, a homopolymer of these monomers or oligomers. Any two refractive index differences may be different. The mixing ratio of monomers or oligomers having a refractive index difference of 0.01 or more is usually in the range of 10:90 to 90:10 by weight ratio. Further, the compatibility of the monomer or oligomer is preferably low to some extent.

  In addition to the above-mentioned monomers or oligomers, the photocurable resin composition can be used in a range that does not interfere with light controllability, for example, polypropylene, polyethylene, polystyrene, polymethyl methacrylate, polyethylene oxide, polyvinyl pyrrolidone, polyvinyl alcohol, nylon, etc. Polymers such as toluene, n-hexane, cyclohexane, methyl alcohol, ethyl alcohol, acetone, methyl ethyl ketone, tetrahydrofuran, ethyl acetate, dimethylformamide, dimethylacetamide, acetonitrile, etc., organic halogen compounds, organosilicon compounds, plastics Plastic additives such as an agent and a stabilizer may be contained.

  When the photocurable resin composition is encapsulated in a cell to form a film, a photopolymerization initiator is not necessarily required because it is shielded from oxygen, but the photocurable resin composition is applied onto the substrate. In order to improve the degree of curing, it is desirable to mix a photopolymerization initiator in advance. Examples of the photopolymerization initiator that can be used here include benzophenone, benzyl, Michler ketone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, benzoin methyl ether, benzoin ethyl ether, diethoxyacetophenone, benzyldimethyl ketal, and 2-hydroxy. -2-methylpropiophenone, 1-hydroxycyclohexyl phenyl ketone and the like. The mixing amount of the photopolymerization initiator is usually in the range of 0.01 to 5 parts by weight, more preferably in the range of 0.1 to 3 parts by weight with respect to 100 parts by weight of the photocurable resin composition.

  By irradiating light to such a resin composition film, the photocurable resin composition is cured, and a layer having a special structure for scattering incident light is formed inside the film-like body. This layer is considered to have a structure in which microstructures having different refractive indexes are arranged in parallel in a specific direction. When the film thickness of the resin composition film is too small, formation of this microstructure layer is hindered. As the film thickness increases, the thickness of the microstructure layer also increases, and the light scattering performance (cloudiness value) increases, which is preferable. A suitable film thickness is 25 μm or more as described above.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these examples at all.

Example 1
For polypropylene glycol having an average molecular weight of about 3,000 and 40 parts by weight of polyether urethane acrylate (refractive index of 1.460) obtained by the reaction of toluene diisocyanate, hexamethylene diisocyanate and 2-hydroxyethyl acrylate, 2,4 , 6-tribromophenyl acrylate (I) 55 parts by weight (refractive index 1.58), 2,4-di-t-pentylphenyl acrylate 5 parts by weight and 2-hydroxy-2-methylpropiophenone (polymerization started) Agent) A photocurable resin composition mixed with 1.5 parts by weight was applied to a glass substrate on which a PET film having a thickness of 188 μm was pasted to a thickness of 240 μm.
And the produced resin composition film | membrane was irradiated with the ultraviolet-ray using the apparatus shown in FIG. 1, the photocurable resin composition was hardened, and the light control film | membrane was obtained. Here, the reflector 4 is a parallel light type, the light source lamp 3 is a linear mercury lamp of 80 W / cm, the moving speed of the conveyor 1 is 5.0 m / min, and the distance between the light source lamp 3 and the resin composition film is The distance between the light shielding plate 5 and the resin composition film was 10 cm. The opening 51 of the light shielding plate 5 was formed such that the light irradiation start angle was −1.5 ° and the light irradiation end angle was + 25 ° with respect to the normal line of the resin composition film surface.

  About the obtained light control film | membrane, the haze value was measured with the glass substrate as follows. The haze value of the glass substrate itself can be ignored. The incident angle dependence of the haze value of the light control film was measured in the same direction as the moving direction of the conveyor. FIG. 3 shows the measured haze curve. In addition, Table 1 shows the maximum haze value, the minimum haze value, and the light scattering angle region where the haze value is 60% or more determined from the haze curve.

(Measurement of haze)
The haze value is obtained by using an integrating sphere light transmittance measuring device (Hazeguard Plus 4725 manufactured by Gardner) and setting the distance between the center of the light control film and the integrating sphere to 4 cm, and the total light transmittance of the light control film and The diffuse transmittance was measured and determined by the following formula.

  Further, the angle dependency of the haze value in the light control film was measured as follows. That is, as shown in FIG. 6, by changing the incident angle θ of the light to the test piece 8 of the light control film between 0 to 180 °, the above-described haze value is measured for each angle, and 60% The angle range showing the above haze value is defined as a light scattering angle region. Here, the angle θ is an angle formed between the light incident surface of the test piece 8 and the incident light, and the rotation of the test piece 8 is performed in a direction in which the angle dependency of the haze value is maximized. A and B shown in the figure are the same figure (a) (when light is incident on the test piece 8 from the vertical direction: θ = 90 °) and the same figure (b) (light is incident on the test piece 8 from the oblique direction). ), The reference numeral is attached so that the corresponding portion of the test piece 8 can be seen.

(Example 2)
A light control film was prepared in the same manner as in Example 1 except that the moving speed of the conveyor was 2.0 m / min, and the haze value was measured. The haze curve of the obtained light control film is shown in FIG. Table 1 shows the maximum haze value, the minimum haze value, and the light scattering angle region where the haze value is 60% or more obtained from this haze curve.

(Comparative Example 1)
A light control film was prepared in the same manner as in Example 1 except that the condensing reflector 4 ′ using the focal point diffusion point shown in FIG. 5 was used instead of the parallel reflector. The haze curve of the obtained light control film is shown in FIG. Table 1 shows the maximum haze value, the minimum haze value, and the light scattering angle region where the haze value is 60% or more obtained from this haze curve.

(Comparative Example 2)
A light control film was produced in the same manner as in Example 2 except that a condensing reflector 4 ′ (shown in FIG. 5) using a focal point diffusion point was used instead of the parallel reflector. The haze curve of the obtained light control film is shown in FIG. Table 1 shows the maximum haze value, the minimum haze value, and the light scattering angle region where the haze value is 60% or more obtained from this haze curve.

(Comparative Example 3)
A light control film was produced in the same manner as in Comparative Example 1 except that the distance between the light source lamp and the photocurable resin composition film was changed from 80 cm to 43 cm. The haze value curve of the obtained light control film is shown in FIG. Table 1 shows the maximum haze value, the minimum haze value, and the light scattering angle region where the haze value is 60% or more obtained from this haze curve.

(Comparative Example 4)
A light control film was produced in the same manner as in Comparative Example 2 except that the distance between the light source lamp and the photocurable resin composition film was changed from 80 cm to 43 cm. The haze value curve of the obtained light control film is shown in FIG. Table 1 shows the maximum haze value, the minimum haze value, and the light scattering angle region where the haze value is 60% or more obtained from this haze curve.

  According to the manufacturing apparatus and the manufacturing method of the present invention, a photocured film that scatters only incident light from a specific angle and has an angle dependency on the haze can be manufactured with high productivity.

It is a perspective view which shows an example of the manufacturing apparatus which concerns on this invention. It is explanatory drawing of the reflecting plate used with the manufacturing apparatus of FIG. It is a figure which shows the incident angle dependence of the haze in the light control film of Example 1,2. It is a figure which shows the incident angle dependence of the haze in the light control film of Comparative Examples 1-4. It is explanatory drawing of the condensing type reflection plate of a focus diffusion point use type. It is a figure explaining the measuring method of the angle dependence of a haze. It is a perspective view which shows the conventional manufacturing apparatus.

Explanation of symbols

1 conveyor 2 glass substrate 3 light source lamp (linear light source)
4 Reflector (reflective member)
5 Light shielding plate (light shielding member)
51 opening

Claims (5)

A linear light source is disposed so as to face the photocurable resin composition film at a distance, and at least one of the photocurable resin composition film and the linear light source is moved, and light is irradiated from the linear light source for photocuring. A manufacturing apparatus for forming a light control film by curing a functional resin composition film,
The axial direction of the linear light source intersects with the moving direction,
An apparatus for manufacturing a light control film, comprising: a reflection member that reflects light from a linear light source into parallel light and irradiates the photocurable resin composition film.   The plate-shaped light shielding member which has an opening part is further provided between the photocurable resin composition film and the linear light source so as to face the photocurable resin composition film. Light control film manufacturing equipment.   The photocurable resin composition has at least two kinds of photopolymerizable monomers each having a polymerizable carbon-carbon bond in the molecule and having a difference in refractive index of a homopolymer obtained by homopolymerization. 3. The light control film production apparatus according to claim 1, wherein the light control film comprises an oligomer.   Photocurable resin containing at least two kinds of photopolymerizable monomers or oligomers each having a polymerizable carbon-carbon bond in the molecule and having a difference in the refractive index of the homopolymer obtained by homopolymerization The manufacturing method of the light control film | membrane which shape | molds a composition in a film form and hardens a photocurable resin composition film | membrane using the manufacturing apparatus in any one of Claims 1-3.   The method for producing a light control film according to claim 4, wherein the film thickness of the photocurable resin composition film is 25 μm or more.