JP2019128392A - Dimming element and method of manufacturing dimming element - Google Patents

Abstract

To improve adhesion between a polymer matrix and a support plate in a dimming element.SOLUTION: A dimming element 10 comprises a first support plate 11 including a first conductive layer 14, a second support plate 12 including a second conductive layer 17, and a dimming layer 20 placed between the first support plate 11 and the second support plate 12. The dimming layer 20 has a polymer matrix 21 having alignment regulation performance and a liquid crystal molecule 25 held in the polymer matrix 21 and changing alignment by applying voltage to the first conductive layer 14 and the second conductive layer 17.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a light control device including a light control layer having a polymer matrix and liquid crystal molecules, and a method of manufacturing the light control device.

  Conventionally, for example, a polymer dispersed liquid crystal element in which liquid crystal droplets or the like are dispersed in a transparent polymer material is used as a light control element for adjusting the transmittance of incident light. In the polymer-dispersed liquid crystal element, it is possible to switch between a transmission state that transmits incident light and a scattering state that scatters incident light by applying and releasing an electric field to the dispersed liquid crystal. As a polymer dispersed liquid crystal, for example, a transparent polymer material in which liquid crystal droplets are dispersed (PDLC: Polymer Dispersed Liquid Crystal), a polymer resin network is formed in a continuous layer of liquid crystal Examples thereof include polymer network liquid crystal (PNLC) and polymer stabilized cholesteric liquid crystal (PSCT) using cholesteric liquid crystal. Since these polymer dispersed liquid crystals do not need to use a polarizing plate, they have a feature of high light utilization efficiency.

  These polymer dispersed liquid crystal elements are used as light control elements for trains, automobiles, windows of buildings, and are also used for viewing angle control of liquid crystal displays by combining with backlights of liquid crystal displays (patent document 1) It is used as a screen for a projector (Patent Document 2).

Unexamined-Japanese-Patent No. 5-72529 Unexamined-Japanese-Patent No. 6-301005

  In a polymer dispersed liquid crystal element, a normal type liquid crystal element which changes from a scattering state to a transmitting state by application of an electric field to the dispersed liquid crystal material, and scattering from the transmitting state by application of an electric field to the dispersed liquid crystal material There is a reverse type liquid crystal element that changes to a state.

  A light control device including a polymer dispersion type liquid crystal device includes a pair of transparent support plates and a light control layer disposed between the pair of transparent support plates. The transparent support plate includes a transparent substrate and a transparent electrode formed on the transparent substrate. When the polymer dispersed liquid crystal element is a reverse type liquid crystal element, the light control layer has a configuration in which a liquid crystal material having negative dielectric anisotropy is dispersed in a polymer matrix. In the reverse type liquid crystal element, an alignment film having a pretilt angle of 90 ° is usually formed on the transparent electrode of the transparent support plate, whereby the liquid crystal molecules in the liquid crystal material can be applied when no electric field is applied to the light control layer. Is homeotropically oriented.

  In order for the liquid crystal molecules in the liquid crystal material to be homeotropically aligned when no electric field is applied to the light control layer, the liquid crystal molecules need to be in direct contact with the alignment film. Therefore, in the conventional reverse type liquid crystal device, the contact area between the polymer matrix and the alignment film can not be increased, and the adhesion between the light control layer and the alignment film may not be sufficient. In this case, the light control layer is peeled off from the transparent support plate (alignment film), and the light incident on the light control element is unintentionally refracted at the peeled portion, thereby reducing the transparency of the light control element in the transparent state. Can be invited.

  The present invention has been made in consideration of the above points, and an object thereof is to improve the adhesion between a polymer matrix and a support plate in a light control element.

The light control device of the present invention is
A first support plate including a first conductive layer;
A second support plate including a second conductive layer;
A light control layer disposed between the first support plate and the second support plate;
The light control layer includes a polymer matrix having an alignment regulating ability, and liquid crystal molecules that are held in the polymer matrix and change orientation by applying a voltage to the first conductive layer and the second conductive layer. .

In the light control device of the present invention,
The polymer matrix may contain a cured polymerizable liquid crystal.

In the light control device of the present invention,
The polymer matrix may further contain a cured polymerizable resin.

In the light control device of the present invention,
The ratio of the weight of the polymerizable liquid crystal to the total weight of the polymerizable liquid crystal and the polymerizable resin may be 0.50 or more and 0.69 or less.

The manufacturing method of the light control element of the present invention is
A first feeding step of feeding the first support plate including the first conductive layer;
A second feeding step of feeding the second support plate including the second conductive layer;
Applying a liquid crystal mixed material containing a polymerizable liquid crystal and a non-polymerizable liquid crystal on the first support plate or the second support plate;
A bonding step of bonding the first support plate and the second support plate via the liquid crystal mixed material;
And curing the polymerizable liquid crystal.

In the method for manufacturing the light control device of the present invention,
The liquid crystal mixed material further contains a polymerizable resin,
In the curing step, the polymerizable liquid crystal and the polymerizable resin may be cured.

  The ratio of the weight of the polymerizable liquid crystal to the total weight of the polymerizable liquid crystal and the polymerizable resin may be 0.50 or more and 0.69 or less.

  According to the present invention, the adhesion between the polymer matrix and the support plate in the light control element can be improved.

FIG. 1 is a view for explaining an embodiment according to the present invention, and is a perspective view schematically showing a light control element. FIG. 2 is a view partially showing a cross section of the light control element when no electric field is applied. FIG. 3 is a view partially showing a cross section of the light control element when an electric field is applied. FIG. 4 is a diagram for explaining a method of manufacturing the light control device. FIG. 5 is a graph for explaining the relationship between the voltage applied to the light control element and the haze value in the example.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of easy illustration and understanding, the scale, vertical and horizontal dimensional ratios, etc. are exaggerated and changed from those of a real thing as appropriate.

  In this specification, the terms “plate”, “sheet”, and “film” are not distinguished from each other only based on the difference in designation. For example, “plate” is a concept that includes members that can be called “sheets” and “films”. Therefore, for example, “support plate” is a member called “support sheet” or “support film”. It cannot be distinguished only by the difference in designation.

  In addition, “plate surface (sheet surface, film surface)” refers to a plate-shaped member (sheet-shaped member (sheet-shaped member) when the target plate-shaped (sheet-shaped, film-shaped) member is viewed globally and generally. It refers to the surface that coincides with the plane direction of the member or film-like member. Moreover, the normal direction used with respect to a plate-like (sheet-like, film-like) member refers to the normal direction to the plate face (sheet face, film face) of the member.

  Furthermore, as used in this specification, the shape and geometric conditions and the degree thereof are specified. For example, terms such as “parallel”, “orthogonal”, “identical”, length and angle values, etc. Without being bound by the meaning, it shall be interpreted including the extent to which the same function can be expected.

  1 to 4 are diagrams for explaining an embodiment according to the present invention. Among these, FIG. 1 is a view schematically showing the light control element, FIG. 2 is a view showing a cross section of the light control element when no electric field is applied, and FIG. 3 is a cross section of the light control element when electric field is applied. FIG.

  The light control element 10 of the present embodiment shown in FIGS. 1 to 3 is an element capable of adjusting the degree of scattering when transmitting light incident on the light control element 10. The light control element 10 is provided, for example, in a window of a vehicle such as a train or car, a building such as a house, etc. to control the transparency through the light control element 10 or to be combined with the backlight of the liquid crystal display Therefore, it can be used for viewing angle control of a liquid crystal display. In addition, the use of the light control element 10 is not restricted to these.

  As shown in FIGS. 2 and 3, the light control element 10 includes a first support plate 11, a second support plate 12 disposed opposite to the first support plate 11, and a first support plate 11. And a light control layer 20 disposed between the second support plate 12 and the second support plate 12.

  The first support plate 11 and the second support plate 12 support the light control layer 20 and have a function of applying an electric field to the light control layer 20. The first support plate 11 includes a first base 13, a first transparent conductive layer (first conductive layer) 14 provided on the first base 13, and a first base with respect to the first transparent conductive layer 14. And a first alignment film 15 provided on the opposite side to the material 13. The second support plate 12 has a second base 16, a second transparent conductive layer (second conductive layer) 17 provided on the second base 16, and a second transparent conductive layer 17. 2 and a second alignment film 18 provided on the opposite side of the base material 16. In the illustrated example, the first support plate 11 and the second support plate 12 are arranged to face each other so that the first alignment film 15 and the second alignment film 18 face each other. Therefore, in the illustrated example, the first base material 13, the first transparent conductive layer 14, the first alignment film 15, the light control layer 20, the second alignment film 18, the second transparent conductive layer 17, and the second base material 16. Are stacked in this order.

  The substrates 13 and 16 function as a support for supporting the transparent conductive layers 14 and 17 and the alignment films 15 and 18. The material of the base materials 13 and 16 is not particularly limited, and for example, various transparent film materials having flexibility can be used. Specifically, polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), acrylic resins such as polymethyl methacrylate (PMMA), polyolefin resins such as polypropylene (PP), triacetyl cellulose (cellulose triacetate: A film material containing cellulose resin such as TAC), cycloolefin polymer (COP), polycarbonate (PC) resin, or the like can be used. Moreover, as thickness of the base materials 13 and 16, a thing of 20 micrometers or more and 300 micrometers or less can be used, for example, Preferably a thing of 50 micrometers or more and 150 micrometers or less can be used.

  The transparent conductive layers 14 and 17 function as electrodes that apply an electric field to the light control layer 20 when energized, thereby driving the non-polymerizable liquid crystal 22 included in the light control layer 20. Here, “driving” the non-polymerizable liquid crystal 22 means changing the direction of the liquid crystal molecules 25 included in the non-polymerizable liquid crystal 22. Therefore, by applying an electric field to the light control layer 20 using the transparent conductive layers 14 and 17, the alignment direction of the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22 of the light control layer 20 can be changed. .

  As the transparent conductive layers 14 and 17, it is possible to apply an electric field to the light control layer 20, and it is possible to apply various configurations that are perceived as transparent. For example, transparent conductive materials ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), AZO (Aluminum-doped Zinc Oxide), GZO (Gallium-doped Zinc Oxide), ATO (Antimony Tin Oxide), ZNO (Zinc Oxide) In addition to a metal oxide such as), a material containing a conductive polymer film, silver nanowires, carbon nanotubes, or the like can be used. The sheet resistance and transmittance in the transparent conductive layers 14 and 17 are not particularly limited. For example, the sheet resistance can be 100Ω / □ or more and 300Ω / □ or less, and the transmittance can be 85% or more.

  The alignment films 15 and 18 of the present embodiment are so-called vertical alignment films, and the longitudinal direction of the liquid crystal molecules of the polymerizable liquid crystal contained in the liquid crystal mixture material 27 is along the normal direction of the alignment films 15 and 18. Align liquid crystal molecules. Although the material of the alignment films 15 and 18 is not specifically limited, For example, a polyimide etc. can be used. The thickness of the alignment films 15 and 18 can be, for example, 100 nm or more and 500 nm. When liquid crystal molecules contained in the polymerizable liquid crystal of the liquid crystal mixture material 27 described later are aligned by means other than the alignment films 15 and 18, the alignment films 15 and 18 can be omitted.

  Next, the light control layer 20 will be described. The light control layer 20 has a function of changing the transparency through the light control layer 20 according to the application state of the electric field by the transparent conductive layers 14 and 17. The light control layer 20 is formed of a polymer dispersed liquid crystal. Examples of the polymer-dispersed liquid crystal include, but are not limited to, liquid crystal liquid crystal (PDLC) in which liquid crystal droplets are dispersed in a transparent polymer material. In the present embodiment, as shown in FIG. 2 and FIG. 3, the light control layer 20 is a polymer dispersion type that includes a polymer matrix 21 and a non-polymerizable liquid crystal 22 dispersed in the polymer matrix 21. An example formed by liquid crystal (PDLC: Polymer Dispersed Liquid Crystal) will be described. In addition, the light control layer 20 may include a spacer for keeping the distance between the first support plate 11 and the second support plate 12 at a predetermined distance. As the spacer, for example, a spherical bead spacer made of a transparent resin can be used.

  The light control layer 20 shown in FIG. 2 includes a polymer matrix 21 having an alignment regulating ability, liquid crystal molecules 25 that are held in the polymer matrix 21 and change the alignment by applying a voltage to the transparent conductive layers 14 and 17. Have. The illustrated light control layer 20 has a non-polymerizable liquid crystal 22 dispersed in a polymer matrix 21, and the non-polymerizable liquid crystal 22 includes liquid crystal molecules 25. The polymer matrix 21 contains a cured polymerizable liquid crystal, and may further contain a cured polymerizable resin.

  The non-polymerizable liquid crystal 22 is a liquid material containing liquid crystal molecules 25 having a longitudinal direction and having no polymerization group. The liquid crystal molecules 25 have refractive index anisotropy corresponding to the shape. That is, the refractive index in the direction perpendicular to the longitudinal direction of the liquid crystal molecules 25 is different from the refractive index in the direction parallel to the longitudinal direction of the liquid crystal molecules 25. In particular, in the present embodiment, the light control layer 20 is configured as a reverse type liquid crystal element, and negative liquid crystal molecules are used as the liquid crystal molecules 25 of the non-polymerizable liquid crystal 22. In this case, the orientation of the liquid crystal molecules 25 becomes irregular in a state where an electric field is applied by the transparent conductive layers 14 and 17. Therefore, the light control layer 20 becomes cloudy in the state where the electric field is applied, and thereby the transparency through the light control layer 20 becomes low. On the other hand, in a state where no electric field is applied by the transparent conductive layers 14 and 17, the liquid crystal molecules 25 are aligned along the normal direction of the light control element 10 (light control layer 20). Therefore, the light control layer 20 becomes transparent in the state where the electric field is not applied, whereby the transparency through the light control element 10 becomes high.

  The polymerizable liquid crystal includes liquid crystal molecules having refractive index anisotropy like the non-polymerizable liquid crystal 22, and liquid crystals having any of monofunctional and polyfunctional polymerizable monomers (polymerizable groups) can be used. . As the polymerizable liquid crystal, a photo-curable liquid crystal, particularly an ultraviolet curable liquid crystal can be used. As such a polymerizable liquid crystal, for example, a polymerizable nematic liquid crystal (LC242) manufactured by BASF can be used.

  The polymerizable resin may be made of a material capable of causing phase separation of the non-polymerizable liquid crystal 22 and having high light transmittance, and a resin having any of monofunctional and polyfunctional polymerizable monomers (polymerizable groups) Can also be used. As the polymerizable resin, a photo-curing resin, particularly an ultraviolet-curing resin can be used. Examples of such resins include monofunctional (meth) acrylates such as methyl (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) And (iii) polyfunctional (meth) acrylates such as acrylate, dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate. The term "(meth) acrylate" means acrylate or methacrylate. In addition to acrylics, cation polymerizable monomers include alicyclic epoxides such as 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexenecarboxylate, and glycidyl ethers such as bisphenol A diglycidyl ether. A class etc. can also be used. These polymerizable resins can be used singly or in combination of two or more depending on required performance, coating suitability and the like.

  As the polymerization initiator, various polymerization initiators can be used without limitation. For example, a photopolymerization initiator can be used as the polymerization initiator. As such a polymerization initiator, for example, benzoin and its alkyl etherified products, benzyl ketals, and acetophenones can be used. As acetophenones, for example, hydroxyacetophenone, aminoacetophenone, dialkoxyacetophenone, halogenated acetophenone and the like can be used. As these photopolymerization initiators, for example, products such as Irgacure (registered trademark) 907, Irgacure 651, and Irgacure 184 manufactured by BASF are commercially available, and these can be used alone or in combination.

  The light control layer 20 can be produced, for example, as follows. First, the liquid crystal mixed material 27 having fluidity is prepared by mixing the polymerizable liquid crystal, the polymerizable resin, the polymerization initiator, and the non-polymerizable liquid crystal 22. When the liquid crystal mixed material 27 is disposed in contact with the alignment films 15 and 18, the liquid crystal molecules contained in the polymerizable liquid crystal have the longitudinal direction in the normal direction of the alignment films 15 and 18 (the method of the light control layer 20 Oriented along the line direction). In this state, when the polymerizable liquid crystal and the polymerizable resin contained in the liquid crystal mixed material 27 are polymerized by irradiating the liquid crystal mixed material 27 with ultraviolet light or the like, the polymer matrix is formed from the polymerized (cured) liquid crystal and the polymerizable resin. It is formed. At this time, the liquid crystal molecules contained in the polymerizable liquid crystal are fixed while being aligned so that the longitudinal direction thereof is along the normal direction of the alignment films 15 and 18. The non-polymerizable liquid crystal 22 is phase-separated from the polymerizable liquid crystal and the polymerizable resin and dispersed in the polymer matrix 21 when the polymerizable liquid crystal and the polymerizable resin contained in the liquid crystal mixed material 27 are polymerized. Held in. The polymer matrix 21 of the present embodiment includes liquid crystal molecules that are fixed while being aligned along the normal direction of the light control layer 20. Thereby, the polymer matrix 21 comes to have an alignment control ability (alignment control ability) for aligning the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22 dispersed and held in direct contact with the polymer matrix 21.

The ratio (W ₁ / W _T ) of the weight W ₁ of the polymerizable liquid crystal to the total weight W _T of the cured polymerizable liquid crystal and the polymerizable resin in the light control layer 20 is 0.50 or more and 0.69 or less. Can do. Preferably, W ₁ / W _T can be 0.56 or more and 0.63 or less. When W ₁ / W _T is 0.50 or more, sufficient alignment regulation ability can be imparted to the polymer matrix 21, and when W ₁ / W _T is 0.56 or more, the polymer matrix 21 is more sufficient. It is possible to impart an orientation regulating ability. Further, when W 1 _/ W _T is 0.69 or less, when an electric field is applied to the light modulating layer 20, the liquid crystal molecules 25 included in the non-polymerizable liquid crystal 22 is anti to the alignment regulating force of the polymer matrix 21 to the orientation direction can be appropriately changed, if W 1 _/ W _T is 0.63 or less, when an electric field is applied to the light modulating layer 20, liquid crystal molecules contained in the non-polymerizable liquid crystal 22 25 can change the direction of alignment more appropriately against the alignment control force of the polymer matrix 21.

  In a light control element using a conventional reverse type polymer dispersed liquid crystal element, in order to align the liquid crystal molecules contained in the liquid crystal material dispersed in the polymer matrix when no electric field is applied, the liquid crystal material is an alignment film. It was necessary to be in direct contact. That is, it is necessary to secure a contact area between the liquid crystal material and the alignment film. Thereby, in the conventional light control element, the contact area of a polymer matrix and a support plate cannot be enlarged, and the adhesiveness of a light control layer and an orientation film was not enough.

  In contrast, in the light control device 10 of the present embodiment, the polymer matrix 21 includes liquid crystal molecules that are fixed while being aligned. Thereby, the polymer matrix 21 has an alignment regulating ability (orientation regulating force) for aligning the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22 that is dispersed and held. As a result, as shown in FIG. 2, the non-polymerizable liquid crystal 22 is in contact with the polymer matrix 21, and the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22 However, they are oriented so as to be along a specific direction, in particular, along the normal direction of the light control layer 20 in the present embodiment. That is, it is not necessary to secure a contact portion between the non-polymerizable liquid crystal 22 and the alignment films 15 and 18. Therefore, it is possible to increase the contact area between the polymer matrix 21 and the support plates 11 and 12, thereby effectively improving the adhesion between the polymer matrix 21 and the support plates 11 and 12 in the light control element 10. Can be improved.

  By the way, the light control layer 20 may include a dichroic dye dispersed in the polymer matrix 21. Like the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22, the dichroic dye has a longitudinal direction and changes the alignment direction of the liquid crystal molecules 25 by the application / non-application of an electric field, the direction according to the movement To change. And a dichroic dye comes to have a color according to the direction. For this reason, the light control element 10 is maintained in a colorless and transparent or nearly colorless and transparent state in the transmission state (low haze state), while in the scattering state (high haze state), it is not simply white turbid, It can be in an invisible state while having a tint. Here, when the predetermined color is the same color as the portion around the light control element 10 (the portion where the light control element 10 is not provided), the portion of the light control element 10 in the scattering state of the light control element 10 Only can prevent the appearance of the surrounding part is different. Alternatively, the design including the light control element 10 may be positively provided by setting the color of the light control element 10 in the scattering state to be different from the color of the portion around the light control element 10. . As such a dichroic dye, various well-known things as disclosed in, for example, Japanese Patent Application Laid-Open Nos. 2007-009120 and 2011-246411 can be used.

  In addition, a sealing material may be provided on the peripheral portion of the light control element 10. In particular, by providing the sealing material so as to cover the peripheral portion of the light control layer 20, it is possible to prevent the light control layer 20, particularly the non-polymerizable liquid crystal 22, from leaking out. For this reason, when providing a sealing material in the peripheral part of the light control element 10, a sealing material is the observation of the light control layer 20 in the observation from the normal line direction to the plate | board surface of the light control element 10, ie, planar view. It is preferable to have a surrounding shape. As the material of the sealing material, for example, the same resin as that forming the polymer matrix 21 of the light control layer 20 can be used.

  The light adjusting element 10 configured as described above is formed of a reverse type liquid crystal element, and a liquid crystal material including negative type liquid crystal molecules 25 is used as the non-polymerizable liquid crystal 22. In this case, as shown in FIG. 2, the switch 41 for applying a voltage from the power source 40 to the transparent conductive layers 14 and 17 is open (cut), that is, adjusted by the transparent conductive layers 14 and 17. In the state where no electric field is applied to the optical layer 20, the liquid crystal molecules 25 are aligned along a specific direction by the alignment regulating ability (alignment regulating force) of the polymer matrix 21. It is oriented along the normal direction. At this time, the refractive index of the non-polymerizable liquid crystal 22 and the refractive index of the polymer matrix 21 are aligned. In this state, the light incident on the light control element 10 can pass through the light control element 10 without greatly bending the traveling direction. That is, in the state in which the liquid crystal molecules 25 are aligned, the light control element 10 is in the transmission state (low haze state). In this state, the light control element 10 is in a transparent state, and the transparency through the light control element 10 is enhanced.

  On the other hand, as shown in FIG. 3, when the switch 41 is closed (entered), that is, when an electric field is applied to the light control layer 20 by the transparent conductive layers 14 and 17, it is contained in the nonpolymerizable liquid crystal 22. The liquid crystal molecules 25 irregularly change the alignment direction against the alignment control force of the polymer matrix 21. In this state, the light incident on the light control element 10 is scattered with its traveling direction greatly bent. That is, in the state where the liquid crystal molecules 25 are not aligned, the light control device 10 is in a scattering state (high haze state). At this time, the light control element 10 is in a cloudy state, and the visibility through the light control element 10 is lowered.

  As described above, in the light control element 10 of the present embodiment, the light control element 10 is in the scattering state and the transmission state according to the application and non-application of the electric field to the light control layer 20 by the transparent conductive layers 14 and 17. It can be switched by. Therefore, it is possible to easily change the transparency through the light adjustment element 10.

  Next, with reference to FIG. 4, an example of the light control element manufacturing apparatus 30 used to manufacture the light control element 10 will be described. FIG. 4 is a perspective view schematically showing a part of the light control element manufacturing apparatus 30.

  The light control element manufacturing apparatus 30 shown in FIG. 4 includes a first feeding portion 31 for feeding the first support plate 11, a second feeding portion 32 for feeding the second support plate 12, and a liquid crystal mixing. It has the bonding apparatus 34 for bonding the coating device 33 for apply | coating the material 27, and the 1st support plate 11 and the 2nd support plate 12 via the liquid crystal mixed material 27. FIG. Moreover, the light control element manufacturing apparatus 30 polymerizes (hardens) the polymerizable liquid crystal and the polymerizable resin in the liquid crystal mixed material 27 located on the downstream side of the bonding apparatus 34 along the transport direction dc of the first support plate 11. C) curing device 36).

  The first feeding unit 31 includes a first feeding shaft 31a that holds a first support plate roll 11a around which the first support plate 11 is wound. The first feeding shaft 31a is a member to which the first support plate roll 11a in which the elongated first support plate 11 is wound in a roll shape along the longitudinal direction is attached. Moreover, the 2nd feeding part 32 has the 2nd feeding shaft 32a holding the 2nd support plate roll 12a by which the 2nd support plate 12 was wound. The second feeding shaft 32a is a member to which the second support plate roll 12a in which the elongated second support plate 12 is wound in a roll shape along the longitudinal direction is attached. The feeding units 31, 32 are configured to rotate while holding the support plate rolls 11a, 12a by the feed shafts 31a, 32a, and feed the support plates 11, 12 from the support plate rolls 11a, 12a. . For this purpose, the feeding units 31 and 32 have a rotation mechanism (not shown) connected to the feeding shafts 31a and 32a. The rotation mechanism has a transmission mechanism that transmits a driving force from a driving source such as a motor to the feeding shafts 31a and 32a. In the illustrated example, the feeding shafts 31 a and 32 a extend in a direction parallel to the horizontal direction and intersecting the transport direction dc of the first support plate 11. In particular, in the illustrated example, the feeding shafts 31a and 32a extend in parallel with the horizontal direction and in parallel with the direction (first direction d1) perpendicular to the transport direction dc.

  In the example shown in FIG. 4, the support plate rolls 11 a and 12 a are wound such that the transparent conductive layers 14 and 17 and the alignment films 15 and 18 are located inside the base materials 13 and 16, respectively. . In the first feeding unit 31, the first support plate 11 has the first transparent conductive layer 14 positioned above the first base material 13 and the first alignment film 15 positioned above the first transparent conductive layer 14. In this way, it is unwound from the first support plate roll 11a. Further, the second support plate 12 has a second support so that the second transparent conductive layer 17 is positioned above the second base material 16 and the second alignment film 18 is positioned above the second transparent conductive layer 17. Unwinding from the plate roll 12a.

  The coating device 33 is used for coating the liquid crystal mixed material 27 on the first support plate 11. The coating device 33 applies the liquid crystal mixed material 27 on the first alignment film 15 of the first support plate 11. As the coating device 33, for example, a die coater, a Mayer bar coater, a roll coater, a spray coater or the like can be used.

  In the illustrated example, the first support plate 11 fed from the first feeding unit 31 is applied to the bonding device 34 after the liquid crystal mixed material 27 is applied by the coating device 33. In addition, the traveling direction of the second support plate 12 fed from the second feeding unit 32 is changed by the guide roller 38 and heads toward the bonding device 34. In the bonding apparatus 34, the first support plate 11 and the second support plate 12 are bonded via the liquid crystal mixed material 27. In particular, the first support plate 11 and the second support plate 12 are configured such that the liquid crystal mixed material 27 applied on the first support plate 11 and the second alignment film 18 of the second support plate 12 face each other. Bonded.

  The laminating device 34 has a pair of laminating rollers 35, and the first support plate 11 coated with the liquid crystal mixed material 27 and the second support plate 12 fed from the second support plate roll 12a, The first support plate 11 and the second support plate 12 are bonded via the liquid crystal mixed material 27 by being sandwiched between the pair of bonding rollers 35. In the example shown in FIG. 4, the axis of rotation of the bonding roller 35 extends in parallel with the first direction d1.

  The curing device 36 polymerizes (cures) the polymerizable liquid crystal and the polymerizable resin contained in the liquid crystal mixed material 27 to form the light control layer 20 from the liquid crystal mixed material 27. For example, when the liquid crystal mixed material 27 contains a photopolymerization initiator activated by ultraviolet rays, the curing device 36 may be configured to include an ultraviolet irradiation device. In the example shown in FIG. 4, while the laminate of the first support plate 11, the liquid crystal mixed material 27 and the second support plate 12 passes through the curing device 36, the liquid crystal mixed material 27 is irradiated with ultraviolet light, Thereby, the polymerizable liquid crystal and the polymerizable resin contained in the liquid crystal mixed material 27 are polymerized.

  In the light control element manufacturing apparatus 30, a cutting device for cutting the laminate of the first support plate 11, the light control layer 20 and the second support plate 12 after passing through the curing device 36, the cut laminate A sealing device that seals the peripheral portion of the body with a sealing material, a transport device that transports the laminate, and the like may be provided as appropriate.

  Next, a method of manufacturing the light control device 10 using the light control device manufacturing apparatus 30 will be described. Here, although the example which manufactures the light control element 10 using what is called a roll toe sheet method is demonstrated, it is not restricted to this, For example, you may make it manufacture the light control element 10 using a roll toe roll method.

[Support plate preparation process]
First, the support plates 11 and 12 having the substrates 13 and 16, the transparent conductive layers 14 and 17, and the alignment films 15 and 18 are prepared. Examples of the base materials 13 and 16 include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), acrylic resins such as polymethyl methacrylate (PMMA), polyolefin resins such as polypropylene (PP), and triacetyl cellulose. A film material containing a cellulose resin such as cellulose triacetate (TAC), a cycloolefin polymer (COP), a polycarbonate (PC) resin or the like can be used.

  Transparent conductive layers 14 and 17 are formed on the base materials 13 and 16. For example, the long base materials 13 and 16 are wound in a roll shape, and the base materials 13 and 16 are continuously fed therefrom. The transparent conductive layers 14 and 17 are formed on the fed substrates 13 and 16, and the laminates of the substrates 13 and 16 and the transparent conductive layers 14 and 17 are respectively wound into a roll.

  The transparent conductive layers 14 and 17 are, for example, transparent conductive materials such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), AZO (Aluminum-doped Zinc Oxide), GZO (Gallium-doped Zinc Oxide), and ATO (Antimony Tin Oxide). Oxide), a layer containing a metal oxide such as ZNO (Zinc Oxide), a physical vapor deposition method (PVD method) such as a vacuum deposition method, a sputtering method, an ion plating method, a chemical vapor deposition method ( It can form using CVD method) or the method that combined these 2 or more. When the transparent conductive layers 14 and 17 are formed as a layer containing a conductive polymer material, for example, the conductive polymer material is formed on the substrates 13 and 16 using various coating methods or printing methods, etc. Thus, the transparent conductive layers 14 and 17 can be formed. Further, when the transparent conductive layers 14 and 17 are formed as layers containing silver nanowires, carbon nanotubes, etc., for example, a dispersion liquid in which silver nanowires, carbon nanotubes, etc. are dispersed in a solvent such as water is used as the base material 13, The transparent conductive layers 14 and 17 can be formed by drying after coating on 16.

  Next, alignment films 15 and 18 are formed on the transparent conductive layers 14 and 17 of the laminate of the base materials 13 and 16 and the transparent conductive layers 14 and 17. Thus, the first support plate 11 having the first base material 13, the first transparent conductive layer 14 and the first alignment film 15, and the second base material 16, the second transparent conductive layer 17 and the second alignment film 18 are provided. The second support plate 12 is produced. For example, first, the laminated body wound up in a roll shape is unwound and continuously fed. Alignment films 15 and 18 are formed on the transparent conductive layers 14 and 17 of the fed laminate, that is, on the opposite side of the transparent conductive layers 14 and 17 from the base materials 13 and 16. The alignment films 15 and 18 can be formed, for example, by applying an alignment film material on the transparent conductive layers 14 and 17. Although it does not specifically limit as alignment film material, For example, a polyimide etc. can be used. Then, the produced support plates 11 and 12 are respectively wound up into rolls to produce support plate rolls 11a and 12a.

[First feeding process]
The first support plate 11 is fed from the first support plate roll 11 a held by the first feeding shaft 31 a of the first feeding portion 31. Specifically, the first support plate 11 is unwound from the first support plate roll 11a so that the first transparent conductive layer 14 and the first alignment film 15 are positioned on the upper side of the first base material 13, and the coating device Head to 33.

[Second feeding process]
The second support plate 12 is fed from the second support plate roll 12 a held by the second feed shaft 32 a of the second feed section 32. The advancing direction of the second support plate 12 fed from the second feeding unit 32 is changed by the guide roller 38, and the second support plate 12 is directed to the bonding device 34.

[Coating process]
The liquid crystal mixed material 27 is applied by the applying device 33 on the first support plate 11 fed from the first feeding unit 31. In particular, in the coating device 33, the liquid crystal mixed material 27 is coated on the first transparent conductive layer 14 of the first support plate 11. The liquid crystal mixed material 27 contains at least a non-polymerizable liquid crystal and a polymerizable liquid crystal. In addition, the liquid crystal mixed material 27 may further contain a polymerizable resin. Furthermore, the liquid crystal mixed material 27 may contain a polymerization initiator. In the present embodiment, an example in which the liquid crystal mixed material 27 contains a polymerizable liquid crystal, a polymerizable resin, a polymerization initiator, and a non-polymerizable liquid crystal 22 will be described.

  In the case where the light control layer 20 is provided with a spacer for keeping the distance between the first support plate 11 and the second support plate 12 at a predetermined distance, the spacer is mixed with the liquid crystal mixture material 27 in the coating device 33. It may be applied on the support plate 11. Alternatively, spacers may be prepared separately from the liquid crystal mixture material 27, and for example, after the application process of the liquid crystal mixture material 27, the spacers may be dispersed on the liquid crystal mixture material 27 using a spacer scattering device. In addition, spacers may be sprayed on the second transparent conductive layer 17 of the second support plate 12 using a spacer spraying device. In this case, the first support plate 11 and the second support plate 12 are pressed toward each other by the pair of bonding rollers 35 of the bonding device 34 so that the spacer is embedded in the liquid crystal mixture material 27. Become.

[Bonding process]
Next, using the bonding apparatus 34, the first support plate 11 and the second support plate 12 are bonded via the liquid crystal mixed material 27. In particular, the first support plate 11 and the second support plate 12 are arranged such that the liquid crystal mixed material 27 applied on the first support plate 11 and the second alignment film 18 of the second support plate 12 face each other. Bonded. The bonding apparatus 34 has a pair of bonding rollers 35, and the first support plate 11 and the second support plate 12 are sandwiched by the pair of bonding rollers 35. At this time, the first support plate 11 and the second support plate 12 are pressed toward each other, whereby the thickness of the laminated body of the first support plate 11, the liquid crystal mixed material 27, and the second support plate 12 becomes a pair. It comes to have predetermined thickness corresponding to the interval between pasting rollers 35. In the case where a spacer is embedded in the liquid crystal mixture material 27, the thickness of the liquid crystal mixture material 27 is prevented from being smaller than a predetermined thickness. That is, the thickness of the liquid crystal mixture material 27 is maintained at a predetermined thickness.

  Here, by arranging the liquid crystal mixed material 27 so as to be in contact with the alignment films 15, 18, the longitudinal direction of the liquid crystal molecules of the polymerizable liquid crystal contained in the liquid crystal mixed material 27 is along the specific direction. Oriented. In particular, when a vertical alignment film is used as the alignment films 15 and 18 of the support plates 11 and 12, the liquid crystal mixture material 27 is included in the liquid crystal mixture material 27 by being disposed in contact with the alignment films 15 and 18. The liquid crystal molecules of the polymerizable liquid crystal are aligned so that the longitudinal direction thereof is along the normal direction of the alignment films 15 and 18.

[Curing process]
Next, using the curing device 36, the polymerizable liquid crystal and the polymerizable resin contained in the liquid crystal mixture material 27 are polymerized to cure the liquid crystal mixture material 27. For example, when the liquid crystal mixed material 27 contains a photopolymerization initiator activated by ultraviolet rays, the laminate of the first support plate 11, the liquid crystal mixed material 27, and the second support plate 12 is carried into the curing device 36, The liquid crystal mixed material 27 is irradiated with ultraviolet light by the ultraviolet irradiation device of the curing device 36. The cured liquid crystal mixed material 27 forms the light control layer 20 of the light control element 10.

  When the polymerizable liquid crystal and the polymerizable resin contained in the liquid crystal mixed material 27 are polymerized by irradiating the liquid crystal mixed material 27 with ultraviolet light, the polymer matrix 21 is formed from the polymerized (cured) liquid crystal and the polymerizable resin. The non-polymerizable liquid crystal 22 is phase-separated from the polymerizable liquid crystal and the polymerizable resin, and is held in a state dispersed in the polymer matrix 21 in the form of droplets. At this time, the liquid crystal molecules contained in the polymerizable liquid crystal are fixed while being aligned so that the longitudinal direction thereof is along the normal direction of the alignment films 15 and 18. Thereby, the polymer matrix 21 comes to have an alignment control ability (alignment control ability) for aligning the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22 dispersed and held in direct contact with the polymer matrix 21.

[Cutting process]
Next, the laminated body of the 1st support plate 11, the light control layer 20, and the 2nd support plate 12 is cut | disconnected along the 1st direction d1 using the cutting device which is not shown in figure, and the light control element 10 shown in FIG. To manufacture. If necessary, the peripheral portion of the light control element 10 may be sealed with a sealing material using a sealing device (not shown).

  The light control device 10 according to the present embodiment includes a first support plate 11 including a first conductive layer 14, a second support plate 12 including a second conductive layer 17, and the first support plate 11 and the second support plate 12. And a light control layer 20 disposed between the first and second conductive layers, the light control layer 20 being held in the polymer matrix 21 having the orientation control ability, and the first conductive layer 14 and the second conductive layer Liquid crystal molecules 25 whose orientation is changed by applying a voltage to 17.

  According to such a light control element 10, the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22 are not applied with an electric field only when the non-polymerizable liquid crystal 22 is in contact with the polymer matrix 21 having the alignment control ability. Sometimes the longitudinal direction is oriented along a specific direction. That is, in the light control element 10 of this Embodiment, it is not necessary to ensure the contact part of the nonpolymerizable liquid crystal 22 and the alignment films 15 and 18. Therefore, the contact area between the polymer matrix 21 and the support plates 11 and 12 can be increased, whereby the adhesion between the polymer matrix 21 and the support plates 11 and 12 in the light control element 10 is effectively made. Can be improved.

  In the light control device 10 of the present embodiment, the polymer matrix 21 contains a cured polymerizable liquid crystal.

  In the method of manufacturing a light control device of the present embodiment, a first feeding step of feeding the first support plate 11 including the first conductive layer 14, and a second support plate 12 including the second conductive layer 17 are supplied. A second feeding step of feeding, a coating step of coating a liquid crystal mixed material 27 containing a polymerizable liquid crystal and a non-polymerizable liquid crystal on the first support plate 11 or the second support plate 12, a first support plate 11 And a second support plate 12 through a liquid crystal mixed material 27, and a curing step of curing the polymerizable liquid crystal.

  According to such a light control device 10 and a method for manufacturing the light control device, the cured polymerizable liquid crystal in the polymer matrix 21 exhibits the ability to regulate the alignment of the liquid crystal molecules 25 contained in the non-polymerizable liquid crystal 22. The liquid crystal molecules 25 can be aligned such that the longitudinal direction thereof follows a specific direction when no electric field is applied.

  In the light control device 10 of the present embodiment, the polymer matrix 21 further contains a cured polymerizable resin.

  In the method for manufacturing a light control element according to the present embodiment, the liquid crystal mixed material 27 further contains a polymerizable resin, and the polymerizable liquid crystal and the polymerizable resin are cured in the curing step.

  According to such a light control element 10 and a method for manufacturing the light control element, it is possible to appropriately control the amount of the cured polymerizable resin in the polymer matrix 21 while maintaining the curability of the polymer matrix 21. It becomes. Thereby, the alignment control force with respect to the liquid crystal molecule 25 contained in the non-polymerizable liquid crystal 22 by the polymer matrix 21 can be appropriately controlled.

In the light control device 10 of the present embodiment, the ratio of the weight W ₁ of the polymerizable liquid crystal to the total weight W _T of the polymerizable liquid crystal and the polymerizable resin (W ₁ / W _T ) is 0.50 or more and 0.69. It is as follows.

In the method for manufacturing a light control device according to the present embodiment, the ratio of the weight W ₁ of the polymerizable liquid crystal to the total weight W _T of the polymerizable liquid crystal and the polymerizable resin (W ₁ / W _T ) is 0.50 or more and 0. .69 or less.

According to the manufacturing method of the light control device 10 and the light adjusting device, by W 1 _/ W _T is 0.50 or more, it is possible to impart sufficient orientation regulating ability to the polymer matrix 21. Further, by W 1 _/ W _T is 0.69 or less, when an electric field is applied to the light modulating layer 20, the liquid crystal molecules 25 included in the non-polymerizable liquid crystal 22, the alignment regulating force of the polymer matrix 21 Accordingly, the orientation direction can be appropriately changed.

  Hereinafter, although an example is described, the present invention is not limited to this example.

<Formation of alignment film>
Using liquid crystal materials represented by the following formulas (A) and (B), 80% by mass of a side chain polymer represented by the following formula (A) and 20% by mass of polymerizable liquid crystal represented by the following formula (B) And a photopolymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., Irgacure 907) at a ratio of 5% by mass with respect to the liquid crystal mixture, and dissolved in a toluene solution to a solid content of 5% by mass A leveling agent was added to prepare an alignment film composition liquid.

  An ITO film with a sheet resistance of 150Ω / □ is formed on a 100 μm thick PET film substrate, and the alignment film composition liquid is applied on the ITO film and cured to form a vertical alignment film from the alignment film material. Then, a laminate in which a PET film substrate, an ITO film and a vertical alignment film were sequentially laminated was produced. The film thickness of the vertical alignment film after curing was about 100 nm.

<Preparation of mixed liquid crystal material>
Polymerizable resin with respect to 80 parts by weight of nematic liquid crystal having a negative dielectric anisotropy (dielectric anisotropy Δε = −4.5, refractive index anisotropy Δn = 0.18) as a non-polymerizable liquid crystal X part by weight of isobornyl acrylate as a liquid, Y by weight of LC242 (manufactured by BASF) as a polymerizable liquid crystal, and 0.4 parts by weight of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals, Irgacure 651). The respective liquid crystal mixtures were mixed to prepare six reverse mode liquid crystal mixed materials of sample numbers 1 to 6 shown in Table 1. Table 1 shows the contents of non-polymerizable liquid crystal, polymerizable resin, polymerizable liquid crystal, and photopolymerization initiator (parts by weight) in each sample, and the polymerizability relative to the total weight of the polymerizable liquid crystal and the polymerizable resin. The weight ratio (Y / (X + Y)) of the liquid crystal is shown.

<Fabrication of light control element>
Two laminates having an alignment film formed as described above are prepared, and a spacer dry spray device (SDI-12, manufactured by ING Corporation) is used on one laminate (on the vertical alignment film). A spacer agent having a diameter of 6 μm (manufactured by Sekisui Chemical Co., Ltd., Micropearl SP206) is sprayed, and the mixed liquid crystal material of sample numbers 1 to 6 in Table 1 is applied to the other laminate (on the vertical alignment film) with a Miya bar. did. Then, the two laminates were bonded together so that the respective vertical alignment films face each other, and irradiated with 0.4 mW / cm ² of ultraviolet rays for 10 minutes, and six kinds of light control elements (reverse mode polymer) Dispersion type liquid crystal element was produced.

<Voltage-haze characteristics>
An alternating voltage was applied to the ITO film of each light control element, and the haze value of the light control element was measured according to the method described in JIS K7136. The measurement results are shown in FIG. In FIG. 5, the same sample numbers 1 to 6 are given to light control elements manufactured using the mixed liquid crystal materials of the sample numbers 1 to 6 in Table 1, respectively.

  As is apparent from the measurement results of FIG. 5, the light control elements of sample number 1 where the weight of the polymerizable liquid crystal is 0.38 and sample number 2 of 0.44 with respect to the total weight of the polymerizable liquid crystal and the polymerizable resin. In the above, the haze value hardly changes with the applied voltage, and does not have the performance as the reverse mode PDLC. The light control element of sample number 3 with the ratio of 0.50 appears to behave as reverse mode PDLC, and it is confirmed that the light control element of sample number 4 with the ratio of 0.56 has the highest characteristic. did it. When the ratio of the weight of the polymerizable liquid crystal to the total weight of the polymerizable liquid crystal and the polymerizable resin is further increased, the haze value does not increase even when a high voltage is applied, and the ratio is increased to 0.69. (Dimming element of sample number 6) is almost the same as the dimming element of sample number 5 with the ratio being 0.63, and it can be confirmed that the characteristics are saturated.

DESCRIPTION OF SYMBOLS 10 Light control element 11 1st support plate 11a 1st support plate roll 12 2nd support plate 12a 2nd support plate roll 13 1st base material 14 1st transparent conductive layer 15 1st alignment film 16 2nd base material 17 2nd Transparent conductive layer 18 Second alignment film 20 Light control layer 21 Polymer matrix 22 Non-polymerizable liquid crystal 27 Liquid crystal mixed material 30 Light control element manufacturing device 31 First feed unit 32 Second feed unit 33 Coating device 34 Bonding device 35 Bonding roller 36 curing device

Claims (7)

A first support plate including a first conductive layer;
A second support plate including a second conductive layer;
A light control layer disposed between the first support plate and the second support plate;
The light control layer includes a polymer matrix having an alignment regulating ability, and liquid crystal molecules that are held in the polymer matrix and change orientation by applying a voltage to the first conductive layer and the second conductive layer. , Light control element.   The light control device according to claim 1, wherein the polymer matrix contains a cured polymerizable liquid crystal.   The light control device according to claim 2, wherein the polymer matrix further contains a cured polymerizable resin.   The light control element of Claim 3 whose ratio of the weight of the said polymeric liquid crystal with respect to the total weight of the said polymeric liquid crystal and the said polymeric resin is 0.50 or more and 0.69 or less. A first feeding step of feeding a first support plate including a first conductive layer;
A second feeding step of feeding a second support plate including a second conductive layer;
Applying a liquid crystal mixed material containing a polymerizable liquid crystal and a non-polymerizable liquid crystal on the first support plate or the second support plate;
A bonding step of bonding the first support plate and the second support plate via the liquid crystal mixed material;
And a curing step of curing the polymerizable liquid crystal. The liquid crystal mixed material further contains a polymerizable resin,
The manufacturing method of the light control element of Claim 5 which hardens the said polymeric liquid crystal and the said polymeric resin in the said hardening process.   The method of manufacturing a light control element according to claim 6, wherein a ratio of a weight of the polymerizable liquid crystal to a total weight of the polymerizable liquid crystal and the polymerizable resin is 0.50 or more and 0.69 or less.

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