WO2018230395A1

WO2018230395A1 - Method for producing liquid crystal film and method for producing functional film

Info

Publication number: WO2018230395A1
Application number: PCT/JP2018/021560
Authority: WO
Inventors: 昌孝長谷川; 諭史長野; 寛稲田; 二村　恵朗
Original assignee: 富士フイルム株式会社
Priority date: 2017-06-13
Filing date: 2018-06-05
Publication date: 2018-12-20
Also published as: JPWO2018230395A1; CN110691998A; JP6924832B2; KR102285177B1; KR20190138692A; CN110691998B

Abstract

Provided are: a method for producing a liquid crystal film with high productivity, which enables the achievement of a cholesteric liquid crystal layer that is capable of displaying a fine image with a desired color gradation; and a method for producing a functional film. This method for producing a liquid crystal film sequentially comprises in the following order: a coating step wherein a liquid crystal composition containing a cholesteric liquid crystal compound and a photosensitive chiral agent is applied onto the surface of a supporting body, while conveying the supporting body in the longitudinal direction; an irradiation step wherein a coating film of the liquid crystal composition in an undried state is irradiated with light that has a wavelength at which the chiral agent is photosensitized; an alignment step wherein liquid crystals are aligned by heating the coating film; and a curing step wherein the aligned coating film is cured. In the irradiation step, the coating film is irradiated with light through a patterned mask that is arranged on the supporting body side; and the patterned mask is a gradation patterned mask that has three or more regions having different transmittances with respect to light that has a wavelength at which the chiral agent is photosensitized. By irradiating the coating film with light through the gradation patterned mask in the irradiation step, regions of the coating film are irradiated with light at different irradiances.

Description

Method for producing liquid crystal film and method for producing functional film

The present invention relates to a method for producing a liquid crystal film and a method for producing a functional film.

A layer containing a cholesteric liquid crystal phase (cholesteric liquid crystal layer) is known as a layer having a property of selectively reflecting either right circularly polarized light or left circularly polarized light in a specific wavelength range (selective reflection wavelength range). . For this reason, the cholesteric liquid crystal layer reflects light of a selective reflection wavelength, so that an image of a color corresponding to this can be displayed, and has been developed for various uses.
For example, Patent Document 1 describes a configuration in which a single layer of a cholesteric liquid crystal layer is provided with a region having a selective reflection wavelength band different from other regions in at least one location, and uses the characteristics of cholesteric liquid crystal. To record authentication information.
In Patent Document 1, as a method of forming a cholesteric liquid crystal layer having regions having different selective reflection wavelength bands, a cholesteric liquid crystal layer having a patterned selective reflection wavelength by exposing to ultraviolet rays through a pattern-formed mask. A method of forming is described.

JP 2006-142699 A

However, in the method of forming a cholesteric liquid crystal layer described in Patent Document 1, a cholesteric liquid crystal coating solution is applied to a substrate, dried, and then exposed to ultraviolet rays on the coating film to be cured using a pattern mask. It is carried out. As the pattern mask, only a binary pattern mask having a light shielding part and a transmission part is described.

According to the study by the present inventors, the cholesteric liquid crystal layer formed by such a method has a desired selective reflection wavelength, that is, a region in which a desired color cannot be obtained or a selective reflection wavelength band is different. It was found that the boundary between the images was blurred and sufficient fineness could not be obtained. Further, when a binary pattern mask is used, it is necessary to perform multiple exposures by changing the pattern mask when forming three or more regions having different selective reflection wavelengths in the cholesteric liquid crystal layer. Therefore, it has been found that in order to form a multicolor cholesteric liquid crystal layer, many steps are required and the production efficiency is poor.

In view of the above circumstances, the present invention can provide a cholesteric liquid crystal layer capable of displaying a fine and desired color gradation image, and a method for producing a liquid crystal film and a functional film having high productivity. The task is to do.

As a result of earnestly examining the problems of the prior art, the present inventors have conducted a delivery process of feeding a long support in the longitudinal direction, and the cholesteric liquid crystal compound and the photosensitive material while transporting the delivered support in the longitudinal direction. A coating process for coating a liquid crystal composition containing a chiral agent on the surface of the support; an irradiation process for irradiating the coating film of the liquid crystal composition in an undried state with light having a wavelength at which the chiral agent is sensitive; and heating the coating film. In this order, there is an alignment step for aligning the liquid crystal and a curing step for curing the aligned coating film. In the irradiation step, the coating film is irradiated with light through a pattern mask arranged on the support side, and a pattern is formed. The mask is a multi-tone pattern mask having three or more regions having different transmittances for light having a wavelength to which the chiral agent is exposed. In the irradiation process, light is applied to the coating film through the multi-tone pattern mask. Doing, by irradiating light of different dose for each region of the coating film was found to be able to solve the above problems.
That is, it has been found that the above object can be achieved by the following configuration.

(1) a delivery step of feeding a long support in the longitudinal direction;
An application step of applying a liquid crystal composition containing a cholesteric liquid crystal compound and a photosensitive chiral agent to the support surface while transporting the fed support in the longitudinal direction;
An irradiation step of irradiating the coating film of the undried liquid crystal composition with light having a wavelength at which the chiral agent is sensitive,
An alignment step of aligning the liquid crystal by heating the coating film;
A curing step for curing the oriented coating film, in this order,
In the irradiation process, the coating film is irradiated with light through a pattern mask arranged on the support side,
The pattern mask is a multi-tone pattern mask having three or more regions having different transmittances for light having a wavelength that the chiral agent is sensitive to,
A method for producing a liquid crystal film, wherein, in the irradiation step, light is applied to each region of the coating film by irradiating the coating film with light through a multi-tone pattern mask.
(2) The method for producing a liquid crystal film according to (1), wherein the pattern mask is formed on the back surface of the support.
(3) The pattern mask is formed on the surface of the long base film,
The method for producing a liquid crystal film according to (1), wherein, in the irradiation step, the substrate film on which the pattern mask is formed is attached to the back surface of the support, and the light irradiation is performed.
(4) The method for producing a liquid crystal film according to any one of (1) to (3), wherein the pattern mask is formed by gray scale printing.
(5) The irradiation process has a first irradiation step and a second irradiation step,
The method for producing a liquid crystal film according to any one of (1) to (4), wherein the light irradiation amount in the first irradiation step is smaller than the light irradiation amount in the second irradiation step.
(6) The manufacturing method of the liquid-crystal film as described in (5) whose sum total of the irradiation amount of a 1st irradiation step and a 2nd irradiation step is 200 mJ / cm < ² > or less.
(7) The irradiation process has a first irradiation step and a second irradiation step,
The method for producing a liquid crystal film according to any one of (1) to (6), wherein a peak wavelength of light irradiated in the first irradiation step and a peak wavelength of light irradiated in the second irradiation step are different from each other.
(8) The curing step is a step of photocuring the coating film,
The method for producing a liquid crystal film according to any one of (1) to (7), wherein the wavelength of light irradiated in the curing step is different from the wavelength of light irradiated in the irradiation step.
(9) In the curing step, the pattern mask is integrally conveyed in a state of being arranged on the back side of the support,
The manufacturing method of the liquid crystal film as described in (8) which irradiates light to the surface side on the opposite side to a pattern mask.
(10) The method for producing a liquid crystal film according to any one of (1) to (9), wherein the application method of the liquid crystal composition in the application step is bar application.
(11) A method for producing a liquid crystal film in which a combination of a coating process, an irradiation process, an alignment process, and a curing process is repeated twice or more to form two or more cholesteric liquid crystal layers,
The liquid crystal film according to any one of (1) to (10), wherein light is irradiated through a pattern mask having the same pattern in two or more irradiation steps, and the amount of light irradiation in each irradiation step is different from each other Manufacturing method.
(12) After the curing step of the liquid crystal film production method according to any one of (1) to (11), a step of attaching a circularly polarizing plate to the surface of the cured coating film or the back surface of the support is included. A method for producing a functional film.

According to the present invention, a cholesteric liquid crystal layer capable of displaying a fine and desired color gradation image can be obtained, and a liquid crystal film manufacturing method and a functional film manufacturing method having high productivity can be provided. .

It is a figure which shows typically the manufacturing apparatus which enforces an example of the manufacturing method of the liquid crystal film of this invention. It is a schematic diagram for demonstrating an example of the manufacturing method of the liquid crystal film implemented with the manufacturing apparatus of FIG. It is a figure which shows typically the manufacturing apparatus which enforces another example of the manufacturing method of the liquid crystal film of this invention. It is typical sectional drawing for demonstrating an example of the manufacturing method of the liquid crystal film implemented with the manufacturing apparatus of FIG. It is typical sectional drawing for demonstrating an example of the manufacturing method of the liquid crystal film implemented with the manufacturing apparatus of FIG. It is a figure showing the pattern mask used in the Example. It is a figure showing the liquid crystal film produced in the Example. It is a figure showing another example of the pattern mask used by this invention. It is a figure showing the binary pattern mask used by the comparative example. It is a figure showing an example of the pattern mask used with the manufacturing method of this invention. It is a figure showing the liquid crystal film produced using the pattern mask shown in FIG.

Hereinafter, the manufacturing method of the liquid crystal film of this invention is demonstrated in detail. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
In this specification, “orthogonal” and “parallel” include a range of errors allowed in the technical field to which the present invention belongs. For example, “orthogonal” and “parallel” mean that the angle is within ± 10 ° with respect to strict orthogonality or parallelism, and an error with respect to strict orthogonality or parallelism is 5 ° or less. Preferably, it is 3 ° or less.
Further, an angle represented by other than “orthogonal” and “parallel”, for example, a specific angle such as 15 ° or 45 °, includes a range of errors allowed in the technical field to which the present invention belongs. For example, in the present invention, the angle means less than ± 5 ° with respect to the exact angle shown specifically, and the error with respect to the exact angle shown is ± 3 ° or less. It is preferable that it is ± 1 ° or less.

In this specification, “(meth) acrylate” is used to mean “one or both of acrylate and methacrylate”.
In this specification, “same” includes an error range generally allowed in the technical field. In addition, in the present specification, when “all”, “any” or “entire surface” is used, it includes an error range generally allowed in the technical field in addition to the case of 100%, for example, 99% or more, The case of 95% or more, or 90% or more is included.

Visible light is light having a wavelength visible to the human eye among electromagnetic waves, and indicates light having a wavelength range of 380 nm to 780 nm. Invisible light is light having a wavelength range of less than 380 nm or a wavelength range of more than 780 nm.
Although not limited to this, among visible light, light in the wavelength range of 420 nm to 490 nm is blue light, light in the wavelength range of 495 nm to 570 nm is green light, and light in the range of 620 nm to 750 nm. The light in the wavelength band is red light.
Of the infrared light, near infrared light is an electromagnetic wave having a wavelength range of 780 nm to 2500 nm. Ultraviolet light is light having a wavelength in the range of 10 to 380 nm.
In this specification, the selective reflection wavelength is a half-value transmittance represented by the following formula: T1 / 2 (%), where Tmin (%) is the minimum value of the transmittance of a target object (member). Is the average value of two wavelengths.
Formula for calculating half-value transmittance: T1 / 2 = 100− (100−Tmin) ÷ 2

In the present specification, “haze” means a value measured using a haze meter NDH-2000 manufactured by Nippon Denshoku Industries Co., Ltd.
Theoretically, haze means a value represented by the following equation.
(Scattering transmittance of natural light of 380 to 780 nm) / (scattering transmittance of natural light of 380 to 780 nm + direct transmittance of natural light) × 100%
The scattering transmittance is a value that can be calculated by subtracting the direct transmittance from the obtained omnidirectional transmittance using a spectrophotometer and an integrating sphere unit. The direct transmittance is a transmittance at 0 ° based on a value measured using an integrating sphere unit. That is, the low haze means that the direct transmitted light amount is large in the total transmitted light amount.
The refractive index is a refractive index for light having a wavelength of 589.3 nm.

In this specification, Re (λ) and Rth (λ) represent in-plane retardation and retardation in the thickness direction at the wavelength λ, respectively. Unless otherwise specified, the wavelength λ is 550 nm.
In this specification, Re (λ) and Rth (λ) are values measured at a wavelength λ in AxoScan OPMF-1 (manufactured by Optoscience). By inputting the average refractive index ((Nx + Ny + Nz) / 3) and film thickness (d (μm)) in AxoScan,
Slow axis direction (°)
Re (λ) = R0 (λ)
Rth (λ) = ((Nx + Ny) / 2−Nz) × d
Is calculated.
Note that R0 (λ) is displayed as a numerical value calculated by AxoScan, and means Re (λ).

In this specification, the refractive indexes Nx, Ny, and Nz are measured using an Abbe refractometer (NAR-4T, manufactured by Atago Co., Ltd.) and a sodium lamp (λ = 589 nm) as a light source. Further, when measuring the wavelength dependence, it can be measured in combination with an interference filter by a multi-wavelength Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.).
In addition, values in polymer handbooks (John Wiley & Sons, Inc.) and catalogs of various optical films can be used. The average refractive index values of main optical films are exemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), Polystyrene (1.59).

The method for producing the liquid crystal film of the present invention comprises:
A delivery step of feeding a long support in the longitudinal direction;
An application step of applying a liquid crystal composition containing a cholesteric liquid crystal compound and a photosensitive chiral agent to the support surface while transporting the fed support in the longitudinal direction;
An irradiation step of irradiating the coating film of the undried liquid crystal composition with light having a wavelength at which the chiral agent is sensitive,
An alignment step of aligning the liquid crystal by heating the coating film;
A curing step for curing the oriented coating film, in this order,
In the irradiation process, the coating film is irradiated with light through a pattern mask arranged on the support side,
The pattern mask is a multi-tone pattern mask having three or more regions having different transmittances for light having a wavelength that the chiral agent is sensitive to,
In the irradiation step, a liquid crystal film is produced by irradiating the coating film with light through a multi-tone pattern mask to vary the amount of light irradiation according to the region of the coating film.

Moreover, the method for producing the functional film of the present invention comprises:
It is a manufacturing method of the functional film which has the process of sticking a circularly-polarizing plate on the surface of the hardened coating film or the back surface of a support body after the hardening process of the manufacturing method of the said liquid crystal film.

<Method for producing liquid crystal film>
Below, an example of the suitable embodiment of the manufacturing method of the liquid-crystal film of this invention is demonstrated with reference to drawings.
FIG. 1 is a schematic diagram of an example of a liquid crystal film manufacturing apparatus (hereinafter also referred to as “manufacturing apparatus”) that implements the liquid crystal film manufacturing method of the present invention (hereinafter also referred to as “the manufacturing method of the present invention”). Indicates. FIG. 2 is a schematic diagram for explaining an example of a method for producing a liquid crystal film performed by the production apparatus shown in FIG.
Note that the drawings in the present invention are schematic diagrams, and the size of each part, the relationship between the thicknesses of each layer, the positional relationship, and the like do not necessarily match the actual ones. The same applies to the following figures.

A manufacturing apparatus 100a shown in FIG. 1 uses a long support 12a to manufacture a liquid crystal film by roll-to-roll (hereinafter also referred to as “RtoR”). As is well known, RtoR means that a processed object is sent out from a roll formed by winding a long processed object, and is subjected to processing such as film formation while being conveyed in the longitudinal direction. This is a manufacturing method in which the material is wound again in a roll shape.

For example, the manufacturing apparatus 100a includes a delivery roller 102, a first transport unit 120, a coating unit 150, a second transport unit 122, an exposure unit 152, a heating unit 154, a curing unit 156, and a third transport. Part 124 and winding roller 116. The 1st conveyance part 120, the 2nd conveyance part 122, and the 3rd conveyance part 124 have a roller for conveyance etc., and convey a long to-be-processed object by a predetermined | prescribed path | route.
In addition to the illustrated members, the manufacturing apparatus 100a is provided in a known apparatus that forms a film by coating while transporting a long object to be processed, such as a pair of transport rollers, a guide member for a support, and various sensors. Various members may be included.

In the manufacturing apparatus 100 a, a roll 130 formed by winding a long support 12 a is loaded on the delivery roller 102.
The support 12a is pulled out from the roll 130 and passes through the first transport unit 120, the coating unit 150, the second transport unit 122, the exposure unit 152, the heating unit 154, the curing unit 156, and the third transport unit 124, and a winding roller. A predetermined route reaching 116 is inserted.
In addition, the prepared liquid crystal composition to be a cholesteric liquid crystal layer is supplied to the application nozzle 104 of the application unit 150 to perform application.

In the manufacturing apparatus 100a using RtoR, the feeding of the support 12a from the roll 130 and the winding of the support 12a (laminated film 23d) on which the cholesteric liquid crystal layer 18 is formed are performed in synchronization. Thereby, the liquid crystal composition prepared in the coating unit 150 is applied to the support 12a while the long support 12a is transported in the longitudinal direction along a predetermined transport path, the coating film is exposed in the exposure unit 152, and then Then, the coating film is heated in the heating unit 154 to align the liquid crystal, and further, the curing film 156 is irradiated with ultraviolet rays and / or heated to cure the coating film to form the cholesteric liquid crystal layer 18. Further, a long laminated film 23 d in which the cholesteric liquid crystal layer 18 is formed on the support 12 a in the winding roller 116 is wound in a roll shape to obtain a roll 132.
In the present invention, the liquid crystal film is a film having a cholesteric liquid crystal layer, and in the example shown in FIGS. 1 and 2, a laminated film 23d in which the cholesteric liquid crystal layer 18 is laminated on the surface of the support 12a. Is the liquid crystal film of the present invention. The cholesteric liquid crystal layer 18 may be used in a state of being laminated on the support 12a, or may be used after being peeled from the support 12a.

In the delivery step indicated by S1 in FIG. 2, the support 12a delivered from the roll 130 is obtained by forming a pattern mask on a resin film such as a PET film.

As the resin film forming the support 12a, various known sheet-like materials having transparency that are used as substrates (supports) can be used.

Specifically, low density polyethylene (LDPE), high density polyethylene (HDPE), polyethylene naphthalate (PEN), polyamide (PA), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), Polyacrylonitrile (PAN), polyimide (PI), transparent polyimide, polymethyl methacrylate resin (PMMA), polycarbonate (PC), polyacrylate, polymethacrylate, polypropylene (PP), polystyrene (PS), ABS, cycloolefin Films (resin films) made of various resin materials such as copolymer (COC), cycloolefin polymer (COP), and triacetyl cellulose (TAC) are preferably exemplified.

In the present invention, necessary functions such as a protective layer, an adhesive layer, a light reflection layer, an antireflection layer, a light shielding layer, a planarization layer, a buffer layer, a stress relaxation layer, and a release layer are provided on the surface of such a film. A layer (film) that expresses may be used as the support 12a.

The pattern mask included in the support 12a is a multi-tone pattern mask having three or more regions having different transmittances with respect to light irradiated by an exposure unit 152 (to be described later) (light having a wavelength sensitive to the chiral agent).
Such a pattern mask can be formed, for example, by printing, and a mask having a desired pattern is obtained by printing so that the light transmittance of the ink layer formed on the surface of the resin film varies depending on the region. be able to. Specifically, it can be formed by gray scale printing (see FIG. 6) or color printing (see FIG. 8).

If the thickness of the support 12a is too thin, the supportability is lowered, and there is a possibility that bending or the like may occur during conveyance. On the other hand, if it is too thick, the flexibility may be reduced, making it difficult to transport, increasing the size when wound on a roll, or making it difficult to peel the formed cholesteric liquid crystal layer from the support 12a. .
From the above viewpoint, the thickness of the support 12a is preferably 20 μm to 100 μm, and more preferably 60 μm to 100 μm.

As shown in FIG. 1, the support 12 a sent out from the roll 130 passes through the first transport unit 120 and reaches the coating unit 150. In the application unit 150, the support 12a is applied. In the example shown in FIG. 1, the liquid crystal composition is applied by the application nozzle 104 while the support 12 a is wound around the backup roller 106 during application by the application unit 150. When the coating is performed by a method that can be applied without the backup roller 106 such as bar coating, the backup roller 106 may be omitted.
As shown by S2 in FIG. 2, in the coating process, the coating unit 104 applies a liquid crystal composition containing a cholesteric liquid crystal compound and a photosensitive chiral agent to the surface of the support 12a to form a coating film 21a. A laminated body of the support 12a and the coating film 21a is referred to as a laminated film 23a.
The liquid crystal composition will be described in detail later.

As a coating method in the coating process, a known method such as a coating method such as extrusion coating, gravure coating, die coating, bar coating or applicator coating, or a printing method such as flexographic printing can be applied.
Among these, bar coating is preferable from the viewpoint that uneven coating can be suppressed even if the surface of the support 12a has irregularities (such as irregularities due to an ink layer serving as a pattern mask).

The coating film 21a may be formed on the pattern mask side of the support 12a, but is preferably formed on the surface opposite to the pattern mask. That is, the pattern mask is preferably formed on the surface (back surface) opposite to the surface on which the coating film 21a of the support 12a is formed.

Next, as shown in FIG. 1, the laminated film 23 a passes through the second transport unit 122 and reaches the exposure unit 152. In the exposure unit 152, the laminated film 23a is subjected to an irradiation process.
As shown by S3 in FIG. 2, in the irradiation step, the exposure apparatus 108 irradiates light on the coating film 21a in an undried state from the support 12a side, that is, through a pattern mask. The light irradiated by the exposure device 108 is light having a wavelength at which the chiral agent in the coating film 21a (liquid crystal composition) is exposed. Therefore, the coating film 21b exposed by the exposure process is formed. In the exposed coating film 21b, the photosensitive chiral agent is exposed and its structure changes.
A laminate of the support 12a and the exposed coating film 21b is referred to as a laminate film 23b.

Here, the pattern mask is a multi-tone pattern mask having three or more regions having different transmittances with respect to light having a wavelength to which the chiral agent is sensitive. Therefore, the exposed coating film 21b is irradiated with different amounts of light for each region corresponding to the pattern of the pattern mask.
Here, the amount of change in the structure of the photosensitive chiral agent due to light exposure varies depending on the amount of irradiation. Therefore, the amount of change in the structure change of the chiral agent differs in each region of the exposed coating film 21b in accordance with the pattern of the pattern mask.

What is necessary is just to set the wavelength of the light used for exposure according to the kind etc. of a photosensitive chiral agent.
The light irradiation amount may be set according to the type of the photosensitive chiral agent, the light transmittance of the pattern mask, and the like.

Next, as shown in FIG. 1, the laminated film 23 b is conveyed and reaches the heating unit 154. In the heating device 110, the laminated film 23b is subjected to orientation treatment after the coating film is dried.
As shown by S4 in FIG. 2, in the alignment step, the heated coating film 21b is heated by the heating device 110, so that the liquid crystal compound in the coating film 21b is aligned. By the heat treatment, a coating film 21c in which the liquid crystal compound is aligned according to the structure of the chiral agent is formed.
Here, as described above, in the coating film 21c, there are three or more regions having different exposure amounts. Therefore, each region has a structure in which the length of the helical pitch of the cholesteric liquid crystal phase differs depending on the exposure amount. As will be described in detail later, the selective reflection wavelength in the cholesteric liquid crystal phase depends on the pitch of the helical structure in the cholesteric liquid crystal phase. Accordingly, by forming three or more regions having different helical pitch lengths of the cholesteric liquid crystal phase, three or more regions having different selective reflection wavelengths are formed.
A laminated body of the support 12a and the oriented coating film 21c is referred to as a laminated film 23c.

Next, as shown in FIG. 1, the laminated film 23 c is conveyed and reaches the curing unit 156. In the curing unit 156, the laminated film 23c is subjected to a curing process.
As shown by S <b> 5 in FIG. 2, in the curing step, the oriented coating film 21 c is cured by the curing unit 112 to form the cholesteric liquid crystal layer 18. Thereby, a liquid crystal film having the cholesteric liquid crystal layer 18 is produced. A laminated body of the support 12a and the cholesteric liquid crystal layer 18 is referred to as a laminated film 23d.
As a method for curing the coating film 21c, a known curing method such as photocuring by irradiation with light such as ultraviolet rays and heat curing by heating can be used.
When curing is performed by light irradiation, it is preferable to irradiate the coating film 21c with light from the side opposite to the pattern mask.

Next, the produced liquid crystal film (laminated film 23 d) passes through the third transport unit 124 and is wound in a roll shape by the winding roller 116 to form a roll 132.
Since the cholesteric liquid crystal layer of the produced liquid crystal film has a configuration in which three or more regions having different selective reflection wavelengths are formed in a pattern according to the mask pattern, each region reflects light of the selective reflection wavelength. The image of the color and pattern according to can be displayed.

In a conventional configuration in which a coating film of cholesteric liquid crystal is applied to a substrate and dried, and then exposed to ultraviolet rays on the coating film to be cured, the pattern mask is used to expose the liquid crystal in the coating film by drying. Since the compound is difficult to move, the amount of change in the pitch of the spiral structure of the liquid crystal compound is less than the desired amount of change even when exposure is performed. Therefore, there has been a problem that the desired selective reflection wavelength, that is, the desired color cannot be reproduced.
Even in such a case, if the exposure amount is increased, the desired selective reflection wavelength can be obtained. However, if the exposure amount is large, light leaks to the unexposed portion and the unexposed portion is exposed, and the exposed portion and the unexposed portion are exposed. It has been found that there is a problem that the boundary (between regions having different selective reflection wavelengths) with the portion blurs and fineness cannot be obtained sufficiently.
In the configuration using a binary pattern mask having a light-shielding portion and a transmissive portion as the pattern mask, when the binary pattern mask is used, three or more types of regions having different selective reflection wavelengths are formed in the cholesteric liquid crystal layer. In this case, it is necessary to perform exposure multiple times by changing the pattern mask. Therefore, it has been found that in order to form a multicolor cholesteric liquid crystal layer, many steps are required and the production efficiency is poor.

On the other hand, in the production method of the present invention, before the coating film of the liquid crystal composition is heated and dried, the coating film in an undried state is exposed, so that the liquid crystal compound in the coating film is easy to move, Even with a small exposure amount, the change amount of the pitch of the spiral structure of the liquid crystal compound can be set as a desired change amount. Therefore, a desired selective reflection wavelength can be easily obtained, that is, a desired color can be reproduced. In addition, since the exposure amount is small, it is possible to suppress light from leaking to adjacent regions (regions having different exposure amounts), and a boundary between regions having different selective reflection wavelengths does not blur and a fine image can be obtained. .
In addition, since a multi-tone pattern mask having three or more regions having different transmittances for light having a wavelength to which the chiral agent is sensitive is used as the pattern mask, the selective reflection wavelength of the cholesteric liquid crystal layer is different 3 in one exposure. The above regions can be formed. Therefore, a multicolor cholesteric liquid crystal layer can be efficiently manufactured with few processes.
As described above, the production method of the present invention can obtain a cholesteric liquid crystal layer capable of displaying a fine and desired color gradation image, and has high productivity.

Here, the pattern mask only needs to have three or more regions having different transmittances for light having a wavelength that the chiral agent sensitizes, but from the viewpoint of being able to reproduce more colors and increase the gradation. The pattern mask preferably has 8 or more regions having different transmittances, more preferably 256 or more.

Moreover, in the example shown in FIG. 1, although it was set as the structure which winds the produced liquid crystal film in roll shape, it is not limited to this, As a structure which has a cutting part which cuts the produced liquid crystal film to a predetermined | prescribed magnitude | size. Also good.

Further, when the curing method of the coating film in the curing step is photocuring, the wavelength of light irradiated in the curing step is preferably different from the wavelength of light irradiated in the irradiation step. The wavelength of the light to be irradiated is preferably longer than the wavelength of the light to be irradiated in the curing step. Specifically, the wavelength of the light irradiated in the irradiation step is preferably a wavelength at which the chiral agent is sensitized and a wavelength at which the polymerization initiator is not cleaved.
By differentiating the wavelength of the light to be irradiated between the curing process and the irradiation process, it is possible to suppress the coating film from being cured by light irradiation in the irradiation process, and the amount of change in the pitch of the helical structure of the liquid crystal compound can be changed as desired. It can be an amount.

What is necessary is just to select the wavelength which the chiral agent sensitizes for the wavelength of the light irradiated in an irradiation process according to the kind of chiral agent. Specifically, the wavelength of light irradiated in the irradiation step is preferably 350 nm to 400 nm. That is, it is preferable to use a chiral agent that is sensitive in this wavelength range.
Moreover, what is necessary is just to set the irradiation amount used as a desired selective reflection wavelength as the irradiation amount of the light irradiated in an irradiation process according to the kind etc. of a chiral agent.

What is necessary is just to select the wavelength of the light irradiated in a hardening process according to kinds, such as a polymerization initiator. Specifically, the wavelength of light irradiated in the curing step is preferably 300 nm to 350 nm. That is, it is preferable to use a polymerization initiator capable of initiating a polymerization reaction in this wavelength range.
Moreover, what is necessary is just to set the irradiation amount of the light irradiated in a hardening process according to types, such as a polymerization initiator.

In the example shown in FIG. 1, the light irradiation is performed once in the irradiation step, but the light irradiation may be divided into two or more. For example, the irradiation process may have a first irradiation step and a second irradiation step.
By adopting a configuration in which the light irradiation in the irradiation step is performed twice or more, the structural change of the chiral agent due to exposure can be more suitably adjusted, and a desired selective reflection wavelength can be obtained.

In that case, it is preferable that the light irradiation amount in the first irradiation step is smaller than the light irradiation amount in the second irradiation step.
As for the structural change of the chiral agent, when the total amount of light irradiation is small, the amount of change with respect to the amount of light irradiation increases, and as the total amount of light irradiation increases, the amount of change with respect to the amount of light irradiation decreases. Therefore, the structural change of the chiral agent due to exposure can be more suitably adjusted by making the light irradiation amount in the first irradiation step smaller than the light irradiation amount in the second irradiation step.

Moreover, it is preferable that the irradiation process has a total irradiation amount of the first irradiation step and the second irradiation step of 200 mJ / cm ² or less.
By making the total amount of irradiation 200 mJ / cm ² or less, it is preferable in that exposure of unexposed portions can be prevented.

Moreover, it is good also as a structure which makes the peak wavelength of the light irradiated differ in a 1st irradiation step and a 2nd irradiation step.
By making the peak wavelength of the light in the first irradiation step a wavelength shifted from the peak wavelength of the light sensitive to the chiral agent, and matching the peak wavelength of the light in the second irradiation step with the peak wavelength of the light sensitive to the chiral agent, In effect, the amount of light irradiation can be adjusted.
Specifically, for example, if the light absorption peak of the chiral agent is 365 nm and the spectrum has a base in the range of 250 nm to 450 nm, the first irradiation step irradiates light of 265 nm near the base and the second irradiation. In the step, the irradiation amount of light can be substantially adjusted by irradiating light with a peak of 365 nm.

In the example shown in FIG. 1, the film is wound around the roll 132 immediately after the cholesteric liquid crystal layer 18 is formed. However, before the film is wound around the roll 132, a protective film or the like is attached to the surface of the cholesteric liquid crystal layer 18. You may have the process to do.

Furthermore, as shown by S6 in FIG. 2, after producing a liquid crystal film, it has the process of transferring the cholesteric liquid crystal layer 18 to the circularly-polarizing plate 16, and the functional film which has the cholesteric liquid crystal layer 18 and the circularly-polarizing plate 16 It is good also as a structure which produces.
Specifically, after forming the cholesteric liquid crystal layer 18 and before winding it on the roll 132, the circularly polarizing plate 16 may be adhered to the surface of the cholesteric liquid crystal layer 18, or the cholesteric liquid crystal layer 18 may be formed. After forming, after winding up to the roll 132, it is good also as a structure which loads the roll 132 in a common bonding apparatus, and sticks the circularly-polarizing plate 16 on the surface of the cholesteric liquid crystal layer 18. FIG.
Moreover, after sticking the circularly-polarizing plate 16, you may have the process of peeling the support body 12a.

The circularly polarizing plate 16 is not limited, and a circularly polarizing plate having a configuration in which a linearly polarizing plate and a λ / 4 plate are laminated can be used. The circularly polarizing plate 16 transmits circularly polarized light having a direction opposite to the rotational direction of the circularly polarized light reflected by the cholesteric liquid crystal layer 18.

By adopting a configuration in which the cholesteric liquid crystal layer 18 and the circularly polarizing plate 16 are laminated, of the light incident from the cholesteric liquid crystal layer 18 side (hereinafter also referred to as the surface side), the cholesteric liquid crystal layer 18 has one of the selective reflection wavelengths. The other circularly polarized light is reflected, and other light passes through the cholesteric liquid crystal layer 18 and enters the circularly polarizing plate 16. Of the light incident on the circularly polarizing plate 16, the other circularly polarized light is transmitted through the circularly polarizing plate 16.
On the other hand, light incident from the circularly polarizing plate 16 side (hereinafter also referred to as the back surface side) is converted into the other circularly polarized light by the circularly polarizing plate 16, passes through the circularly polarizing plate 16, and enters the cholesteric liquid crystal layer 18.
The other circularly polarized light that has passed through the circularly polarizing plate 16 is in a direction opposite to the spiral direction of the cholesteric liquid crystal phase of the cholesteric liquid crystal layer 18, and thus is not reflected by the cholesteric liquid crystal layer 18 and is transmitted through the cholesteric liquid crystal layer 18. To do.
Therefore, when the functional film in which the cholesteric liquid crystal layer 18 and the circularly polarizing plate 16 are laminated is observed from the front surface side, the other side of the circularly polarized light that is incident and transmitted from the back surface side causes a scene on the other side of the functional film to be observed. While being visually recognized, light having a selective reflection wavelength in the reflective region of the cholesteric liquid crystal layer 18 is visually recognized. That is, when viewed from the surface side, an image of a pattern corresponding to the pattern shape of the cholesteric liquid crystal layer 18 is visually recognized together with a scene on the other side of the functional film.
On the other hand, when the functional film is observed from the back side, the sight of the other side of the functional film is visually recognized by the left circularly polarized light incident and transmitted from the front side, but the cholesteric liquid crystal layer that can be observed from the front side The image displayed by 18 is not visually recognized.
In this way, the functional film in which the cholesteric liquid crystal layer 18 and the circularly polarizing plate 16 are laminated has transparency, and an image viewed from one surface side (cholesteric liquid crystal layer side) and the other surface side ( It can be set as the film from which the image seen from the circularly-polarizing plate side differs.

An adhesive layer may be provided between the cholesteric liquid crystal layer 18 and the circularly polarizing plate 16.
Moreover, it is not limited to the structure which sticks a circularly-polarizing plate to the surface of a cholesteric liquid crystal layer, The structure which sticks a circularly-polarizing plate to the back surface of a support body may be sufficient. That is, it is good also as a functional film which has a cholesteric liquid crystal layer, a support body, and a circularly-polarizing plate.

Here, in the example shown in FIGS. 1 and 2, the support 12a is configured to have a pattern mask. However, the present invention is not limited thereto, and a film having a pattern mask may be attached to the support. .
In FIG. 3, the manufacturing apparatus which implements another example of the manufacturing method of the liquid crystal film of this invention is shown typically.

The manufacturing apparatus 100b shown in FIG. 3 manufactures a liquid crystal film by RtoR. The manufacturing apparatus 100b includes a feed roller 102, a supply roller 140, a first transport unit 120, a coating unit 150, a second transport unit 122, an exposure unit 152, a heating unit 154, a curing unit 156, and a first transport unit. 3 conveyance section 124, collection roller 144, and winding roller 116.
The manufacturing apparatus 100b shown in FIG. 3 is the same as the manufacturing method by the manufacturing apparatus 100a shown in FIG. 1 except that it includes the supply roller 140 and the collection roller 144, and therefore the same parts are denoted by the same reference numerals and the following description will be given. Do mainly different parts. The manufacturing method using the manufacturing apparatus 100b shown in FIG. 3 is the same as the manufacturing method using the manufacturing apparatus 100a shown in FIG. 1 except that the manufacturing method 100b shown in FIG. In the following description, different steps are mainly performed.

In the manufacturing apparatus 100 b, a roll 130 formed by winding a long support 12 b is loaded on the delivery roller 102. Note that a pattern mask is not formed on the support 12b.
The support 12b is pulled out from the roll 130 and passes through the first transport unit 120, the coating unit 150, the second transport unit 122, the exposure unit 152, the heating unit 110, the curing unit 154, and the third transport unit 124, and a winding roller. A predetermined route reaching 116 is inserted.
In addition, the prepared liquid crystal composition to be a cholesteric liquid crystal layer is filled in a predetermined position of the application unit 104.

Further, the supply roller 140 is loaded with a roll 142 formed by winding a mask film 14 (see FIG. 4) having a base film 20 and an ink layer 22 formed as a pattern mask on the surface of the base film 20. Then, the mask film 14 is pulled out from the roll 142 and inserted through a predetermined transport path from the first transport unit 120 to the third transport unit 124. The supply roller 140 is disposed between the feed roller and the first transport unit 120 in the transport direction of the support 12b.

Also, at the position of the transport roller of the third transport unit 124, the mask film 14 is peeled off from the support 12b, and the mask film 14 peeled off from the support 12b is inserted into the collection roller 144. The collection roller 144 is disposed between the third conveyance unit 124 and the take-up roller 116 in the conveyance direction of the support 12b, and collects the mask film 14 on a roll 146.

In the manufacturing apparatus 100b, the feeding of the support 12b from the roll 130 and the winding of the support 12b (laminated film 23d) on which the cholesteric liquid crystal layer 18 is formed are performed in synchronization.
First, while transporting the long support 12b in the longitudinal direction along a predetermined transport path, the mask film 14 is adhered to the back surface of the support 12b to form a laminated film 25a (see FIG. 4).
Next, the liquid crystal composition prepared in the application unit 104 is applied to the surface of the support 12b to form a laminated film 25b (see FIG. 5).

Next, the exposure unit 152 exposes the coating film. In that case, light is irradiated to the coating film 21a from the mask film 14 side stuck to the support body 12b.
Here, the pattern mask included in the mask film 14 is a multi-tone pattern mask in which three or more regions having different transmittances with respect to light having a wavelength that the chiral agent is sensitive to are formed by the ink layer 22. Therefore, by irradiating the coating film 21a with light through the pattern mask, light having different irradiation amounts is irradiated for each region corresponding to the pattern of the pattern mask, so that three or more regions having different selective reflection wavelengths can be obtained. Can be formed.

In that case, it is preferable to stick the pattern mask (ink layer 22) side to the support 12b.
In the manufacturing method of the present invention, since light is irradiated while transporting the support 12b with RtoR, light is incident on the coating film from various directions. There is a risk that the boundary will blur. Therefore, by sticking the pattern mask to the support 12b and shortening the distance between the pattern mask and the coating film, light leakage can be suppressed and a finer image can be formed.

Next, the coating film is heated in the heating unit 110 to align the liquid crystal, and further, the coating film is cured by irradiating with ultraviolet rays and / or heating in the curing unit 112 to form the cholesteric liquid crystal layer 18, and the mask film 14 is a laminated film 25e having a support 12b and a cholesteric liquid crystal layer 18.
Thereafter, the mask film 14 is peeled from the support 12b. The peeled mask film 14 is wound in a roll shape by the collection roller 144 to form a roll 146.
Further, a long laminated film 23 d in which the cholesteric liquid crystal layer 18 is formed on the support 12 b in the winding roller 116 is wound into a roll shape to form a roll 132.

Thus, it is good also as a structure which sticks the base film (mask film 14) in which the pattern mask was formed on the back surface of a support body, and performs an irradiation process (exposure).
In the example shown in FIG. 3, the application process, the irradiation process, the orientation process, and the curing process are performed with the mask film 14 adhered to the support 12b. However, at least the irradiation process is a mask film. What is necessary is just to perform in the state which adhered 14 to the support body 12b, and may perform other processes in the state which does not adhere the mask film 14. FIG.
For example, the structure which affixes the mask film 14 on the support body 12b after an application | coating process may be sufficient. Or the roll 130 which wound the laminated body in which the mask film 14 was affixed on the support body 12b in roll shape was loaded into the sending-out roller 102, and the laminated body in which the mask film 14 was affixed on the support body 12b was covered. It is good also as a structure sent out as a processed material.
For example, the structure which peels the mask film 14 between an irradiation process and an orientation process may be sufficient, and the structure which peels the mask film 14 between an orientation process and a hardening process may be sufficient. Alternatively, a configuration may be employed in which the mask film 14 is not peeled off and is wound into a roll shape with the mask film 14 being laminated on the winding roller 116 to form the roll 132.

In the curing step, when the mask film 14 is attached to the support 12b, it is preferable to irradiate the surface opposite to the mask film 14 with light.

Here, in the example shown in FIGS. 1 and 2, the single cholesteric liquid crystal layer 18 is formed on the support 12a. However, the present invention is not limited to this, and a coating process, an irradiation process, an alignment process, and A combination of the curing steps may be performed twice or more to form two or more cholesteric liquid crystal layers.
For example, a structure in which a cholesteric liquid crystal layer is formed on a cholesteric liquid crystal layer may be provided by supplying a support on which a cholesteric liquid crystal layer is formed to a manufacturing apparatus again as an object to be processed. Or it is good also as a structure which a manufacturing apparatus has two or more combinations of an application part, an exposure part, a heating part, and a hardening part between a sending-out roller and a winding roller in the conveyance direction of a support body.

When two or more irradiation steps are performed, it is preferable to irradiate light through a pattern mask having the same pattern, and to make the amount of light irradiation in each irradiation step different from each other.
Thereby, when viewed from the direction perpendicular to the surface of the cholesteric liquid crystal layer, the selective reflection wavelengths at the same position are different in each cholesteric liquid crystal layer. With this configuration, a color in which light having selective reflection wavelengths of a plurality of cholesteric liquid crystal layers is mixed is visually recognized. That is, various colors can be reproduced. For example, the cholesteric liquid crystal layer has a three-layer configuration, and each cholesteric liquid crystal layer reflects red, green, and blue, respectively, so that white can be reproduced.

(Cholesteric liquid crystal layer)
Next, the cholesteric liquid crystal layer will be described.
A cholesteric liquid crystal layer refers to a layer containing a cholesteric liquid crystal phase. The cholesteric liquid crystal layer is a layer formed by fixing a cholesteric liquid crystal phase.
The cholesteric liquid crystal layer reflects right circularly polarized light or left circularly polarized light of light having a selective reflection wavelength, and transmits the other circularly polarized light having a selective reflection wavelength and light in other wavelength regions.

The structure in which the cholesteric liquid crystal phase is fixed may be a structure in which the alignment of the liquid crystal compound that is the cholesteric liquid crystal phase is maintained. Typically, the polymerizable liquid crystal compound is in an alignment state of the cholesteric liquid crystal phase. Thus, any structure may be used as long as it is polymerized and cured by ultraviolet irradiation, heating, or the like to form a layer having no fluidity, and at the same time, the orientation state is not changed by an external field or an external force. In the structure in which the cholesteric liquid crystal phase is fixed, it is sufficient that the optical properties of the cholesteric liquid crystal phase are maintained, and the liquid crystal compound may no longer exhibit liquid crystallinity. For example, the polymerizable liquid crystal compound may have a high molecular weight due to a curing reaction and may no longer have liquid crystallinity.

The selective reflection wavelength λ of the cholesteric liquid crystal phase depends on the pitch P (= spiral period) of the helical structure in the cholesteric liquid crystal phase, and follows the relationship between the average refractive index n of the cholesteric liquid crystal phase and λ = n × P. Therefore, the selective reflection wavelength can be adjusted by adjusting the pitch of the spiral structure. Since the pitch of the cholesteric liquid crystal phase depends on the kind of chiral agent used together with the polymerizable liquid crystal compound or the concentration of the chiral agent, the desired pitch can be obtained by adjusting these.
Further, the half-value width Δλ (nm) of the selective reflection band (circular polarization reflection band) indicating selective reflection depends on the refractive index anisotropy Δn of the cholesteric liquid crystal phase and the helical pitch P, and Δλ = Δn × P Follow the relationship. Therefore, the width of the selective reflection band can be controlled by adjusting Δn. Δn can be adjusted by the type of liquid crystal compound forming the cholesteric liquid crystal layer, the mixing ratio thereof, and the temperature during alignment. It is also known that the reflectance in the cholesteric liquid crystal phase depends on Δn. When obtaining a similar reflectance, the larger the Δn, the smaller the number of spiral pitches, that is, the thinner the film thickness. Can do.
For the measurement of spiral sense and pitch, it is possible to use the method described in “Introduction to Liquid Crystal Chemistry Experiments”, edited by the Japanese Liquid Crystal Society, Sigma Publishing 2007, page 46, and “Liquid Crystal Handbook”, Liquid Crystal Handbook Editorial Committee Maruzen 196 pages. it can.

The reflected light of the cholesteric liquid crystal phase is circularly polarized. Whether the reflected light is right-handed circularly polarized light or left-handed circularly polarized light depends on the twist direction of the spiral in the cholesteric liquid crystal phase. The selective reflection of circularly polarized light by the cholesteric liquid crystal phase reflects right circularly polarized light when the twist direction of the spiral of the cholesteric liquid crystal phase is right, and reflects left circularly polarized light when the twist direction of the spiral is left.
The direction of rotation of the cholesteric liquid crystal phase can be adjusted by the type of liquid crystal compound forming the cholesteric liquid crystal layer or the type of chiral agent added.

広く Widening the wavelength range of reflected light can be realized by sequentially laminating layers with different selective reflection wavelengths λ. Also known is a technique for expanding the wavelength range by stepwise changing the spiral pitch in the layer called the pitch gradient method. Specifically, Nature 378, 467-469 (1995), Examples include the methods described in Japanese Patent No. 281814 and Japanese Patent No. 4990426.

In the present invention, the selective reflection wavelength in the region of the cholesteric liquid crystal layer can be set in any range of visible light (about 380 to 780 nm) and near infrared light (about 780 to 2000 nm). The method is as described above.

Here, as described above, in the liquid crystal film produced by the production method of the present invention, the cholesteric liquid crystal layer has three or more regions having different selective reflection wavelengths.
For example, the cholesteric liquid crystal layer has a region where red light (light having a wavelength range of 620 nm to 750 nm) is selected as a selective reflection wavelength, a region where green light (light having a wavelength range of 495 nm to 570 nm) is a selective reflection wavelength, and a blue color A configuration in which light (light in a wavelength region of 420 nm to 490 nm) is a selective reflection wavelength can be employed.
Moreover, you may have a reflective area | region which uses infrared rays as a selective reflection wavelength. Note that infrared rays are light in a wavelength region exceeding 780 nm and 1 mm or less, and among these, near-infrared regions are light in a wavelength region exceeding 780 nm and 2000 nm or less.

(Liquid crystal composition)
Examples of the material used for forming the cholesteric liquid crystal layer include a liquid crystal composition containing a liquid crystal compound and a photosensitive chiral agent. The liquid crystal compound is preferably a polymerizable liquid crystal compound.
The liquid crystal composition containing a polymerizable liquid crystal compound may further contain a surfactant, a polymerization initiator, and the like.

--Polymerizable liquid crystal compound--
The polymerizable liquid crystal compound may be a rod-like liquid crystal compound or a disk-like liquid crystal compound, but is preferably a rod-like liquid crystal compound.
Examples of the rod-like polymerizable liquid crystal compound forming the cholesteric liquid crystal layer include a rod-like nematic liquid crystal compound. Examples of rod-like nematic liquid crystal compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines. , Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used. Not only low-molecular liquid crystal compounds but also high-molecular liquid crystal compounds can be used.

The polymerizable liquid crystal compound can be obtained by introducing a polymerizable group into the liquid crystal compound. Examples of the polymerizable group include an unsaturated polymerizable group, an epoxy group, and an aziridinyl group, preferably an unsaturated polymerizable group, and particularly preferably an ethylenically unsaturated polymerizable group. The polymerizable group can be introduced into the molecule of the liquid crystal compound by various methods. The number of polymerizable groups possessed by the polymerizable liquid crystal compound is preferably 1 to 6, more preferably 1 to 3. Examples of polymerizable liquid crystal compounds are described in Makromol. Chem. , 190, 2255 (1989), Advanced Materials, Volume 5, 107 (1993), US Pat. Nos. 4,683,327, 5,622,648, and 5770107, International Publication WO95 / 22586. No. 95/24455, No. 97/00600, No. 98/23580, No. 98/52905, JP-A-1-272551, JP-A-6-16616, and JP-A-7-110469. 11-80081 and JP-A-2001-328773, and the like. Two or more kinds of polymerizable liquid crystal compounds may be used in combination. When two or more kinds of polymerizable liquid crystal compounds are used in combination, the alignment temperature can be lowered.

Specific examples of the polymerizable liquid crystal compound include compounds represented by the following formulas (1) to (11).

[In the compound (11), X ¹ is 2 to 5 (integer). ]

Further, as polymerizable liquid crystal compounds other than the above, cyclic organopolysiloxane compounds having a cholesteric phase as disclosed in JP-A-57-165480 can be used. Further, the above-mentioned polymer liquid crystal compound includes a polymer in which a mesogenic group exhibiting liquid crystal is introduced into the main chain, a side chain, or both positions of the main chain and the side chain, and a polymer cholesteric in which a cholesteryl group is introduced into the side chain. A liquid crystal, a liquid crystalline polymer as disclosed in JP-A-9-133810, a liquid crystalline polymer as disclosed in JP-A-11-293252, or the like can be used.

The addition amount of the polymerizable liquid crystal compound in the liquid crystal composition is preferably 75 to 99.9% by mass with respect to the solid content mass (mass excluding the solvent) of the liquid crystal composition, and preferably 80 to 99. More preferably, it is more preferably 85% to 90% by weight.

--Chiral agent (optically active compound)-
The chiral agent has a function of inducing a helical structure of a cholesteric liquid crystal phase. The chiral compound may be selected according to the purpose because the twist direction or the spiral pitch of the spiral induced by the compound is different.
The chiral agent is not particularly limited, and is a known compound (for example, liquid crystal device handbook, Chapter 3-4-3, TN (twisted nematic), chiral agent for STN (Super-twisted nematic), 199 pages, Japanese academics). Japan Society for the Promotion of Science, 142nd edition, 1989), isosorbide and isomannide derivatives can be used.
A chiral agent generally contains an asymmetric carbon atom, but an axially asymmetric compound or a planar asymmetric compound containing no asymmetric carbon atom can also be used as the chiral agent. Examples of the axial asymmetric compound or the planar asymmetric compound include binaphthyl, helicene, paracyclophane, and derivatives thereof. The chiral agent may have a polymerizable group. When both the chiral agent and the liquid crystal compound have a polymerizable group, they are derived from the repeating unit derived from the polymerizable liquid crystal compound and the chiral agent by a polymerization reaction between the polymerizable chiral agent and the polymerizable liquid crystal compound. A polymer having repeating units can be formed. In this aspect, the polymerizable group possessed by the polymerizable chiral agent is preferably the same group as the polymerizable group possessed by the polymerizable liquid crystal compound. Therefore, the polymerizable group of the chiral agent is also preferably an unsaturated polymerizable group, an epoxy group or an aziridinyl group, more preferably an unsaturated polymerizable group, and an ethylenically unsaturated polymerizable group. Particularly preferred.
The chiral agent may be a liquid crystal compound.

As described above, when the cholesteric liquid crystal layer is manufactured, the size of the helical pitch of the cholesteric liquid crystal phase is controlled by light irradiation. Therefore, a chiral agent (also called a photosensitive chiral agent) that can change the helical pitch of the cholesteric liquid crystal phase in response to light is used.
A photosensitive chiral agent is a compound that changes its structure by absorbing light and can change the helical pitch of the cholesteric liquid crystal phase. As such a compound, a compound that causes at least one of a photoisomerization reaction, a photodimerization reaction, and a photolysis reaction is preferable.
A compound that undergoes a photoisomerization reaction refers to a compound that undergoes stereoisomerization or structural isomerization by the action of light. As a photoisomerization compound, an azobenzene compound, a spiropyran compound, etc. are mentioned, for example.
The compound that causes a photodimerization reaction refers to a compound that undergoes an addition reaction between two groups upon irradiation with light to cyclize. Examples of the photodimerization compound include cinnamic acid derivatives, coumarin derivatives, chalcone derivatives, and benzophenone derivatives.

Preferred examples of the photosensitive chiral agent include chiral agents represented by the following general formula (I). This chiral agent can change the alignment structure such as the helical pitch (twisting force, helix twisting angle) of the cholesteric liquid crystal phase according to the amount of light upon light irradiation.

In general formula (I), Ar ¹ and Ar ² represent an aryl group or a heteroaromatic ring group.
The aryl group represented by Ar ¹ and Ar ² may have a substituent, preferably has a total carbon number of 6 to 40, more preferably a total carbon number of 6 to 30. Examples of the substituent include a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a hydroxyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, a carboxyl group, a cyano group, or a heterocyclic ring. Group is preferred, and a halogen atom, alkyl group, alkenyl group, alkoxy group, hydroxyl group, acyloxy group, alkoxycarbonyl group or aryloxycarbonyl group is more preferred.

Among such aryl groups, aryl groups represented by the following general formula (III) or (IV) are preferable.

R ¹ in the general formula (III) and R ² in the general formula (IV) are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an alkoxy group, A hydroxyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, a carboxyl group, or a cyano group is represented. Among these, a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an aryl group, an alkoxy group, a hydroxyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, or an acyloxy group is preferable, and an alkoxy group, a hydroxyl group, or an acyloxy group is preferable. Is more preferable.
L ¹ in the general formula (III) and L ² in the general formula (IV) each independently represent a halogen atom, an alkyl group, an alkoxy group, or a hydroxyl group, and an alkoxy group having 1 to 10 carbon atoms, Or a hydroxyl group is preferable.
l represents an integer of 0, 1 to 4, with 0 and 1 being preferred. m represents an integer of 0, 1 to 6, with 0 and 1 being preferred. When l and m are 2 or more, L ¹ and L ² may represent different groups.

The heteroaromatic ring group represented by Ar ¹ and Ar ² may have a substituent, preferably has a total carbon number of 4 to 40, and more preferably a total carbon number of 4 to 30. As the substituent, for example, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a hydroxyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, or a cyano group is preferable. A halogen atom, an alkyl group, an alkenyl group, an aryl group, an alkoxy group, or an acyloxy group is more preferable.
Examples of the heteroaromatic ring group include a pyridyl group, a pyrimidinyl group, a furyl group, and a benzofuranyl group. Among them, a pyridyl group or a pyrimidinyl group is preferable.

The content of the chiral agent in the liquid crystal composition is preferably 0.01 mol% to 200 mol%, more preferably 1 mol% to 30 mol% of the amount of the polymerizable liquid crystal compound.

--Polymerization initiator--
When the liquid crystal composition contains a polymerizable compound, it preferably contains a polymerization initiator. In the embodiment in which the polymerization reaction is advanced by ultraviolet irradiation, the polymerization initiator to be used is preferably a photopolymerization initiator that can start the polymerization reaction by ultraviolet irradiation. Examples of photopolymerization initiators include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in US Pat. No. 2,448,828), α-hydrocarbon substituted aromatics. Group acyloin compounds (described in US Pat. No. 2,722,512), polynuclear quinone compounds (described in US Pat. Nos. 3,046,127 and 2,951,758), a combination of triarylimidazole dimer and p-aminophenyl ketone (US patent) No. 3549367), acridine and phenazine compounds (JP-A-60-105667, US Pat. No. 4,239,850), oxadiazole compounds (US Pat. No. 4,221,970), and the like. .
The content of the photopolymerization initiator in the liquid crystal composition is preferably 0.1 to 20% by mass, and preferably 0.5 to 12% by mass with respect to the content of the polymerizable liquid crystal compound. Further preferred.

-Crosslinking agent-
The liquid crystal composition may optionally contain a crosslinking agent in order to improve the film strength after curing and improve the durability. As the cross-linking agent, one that can be cured by ultraviolet rays, heat, moisture, or the like can be suitably used.
There is no restriction | limiting in particular as a crosslinking agent, According to the objective, it can select suitably, For example, polyfunctional acrylate compounds, such as a trimethylol propane tri (meth) acrylate and pentaerythritol tri (meth) acrylate; Glycidyl (meth) acrylate , Epoxy compounds such as ethylene glycol diglycidyl ether; aziridine compounds such as 2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], 4,4-bis (ethyleneiminocarbonylamino) diphenylmethane; hexa Isocyanate compounds such as methylene diisocyanate and biuret type isocyanate; polyoxazoline compounds having an oxazoline group in the side chain; vinyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylto Alkoxysilane compounds such as methoxy silane. Moreover, a well-known catalyst can be used according to the reactivity of a crosslinking agent, and productivity can be improved in addition to membrane strength and durability improvement. These may be used individually by 1 type and may use 2 or more types together.
The content of the crosslinking agent is preferably 3% by mass to 20% by mass, and more preferably 5% by mass to 15% by mass. When the content of the crosslinking agent is less than 3% by mass, the effect of improving the crosslinking density may not be obtained. When the content exceeds 20% by mass, the stability of the cholesteric liquid crystal layer may be decreased.

-Other additives-
In the liquid crystal composition, if necessary, a surfactant, a polymerization inhibitor, an antioxidant, a horizontal alignment agent, an ultraviolet absorber, a light stabilizer, a colorant, metal oxide fine particles, etc. are optically added. It can be added as long as the performance is not lowered.

The liquid crystal composition may contain a solvent. There is no restriction | limiting in particular as a solvent, Although it can select suitably according to the objective, An organic solvent is used preferably.
The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. For example, ketones such as methyl ethyl ketone and methyl isobutyl ketone, alkyl halides, amides, sulfoxides, heterocyclic compounds, hydrocarbons , Esters, ethers and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, ketones are particularly preferable in consideration of environmental load. The above-described components such as the above-mentioned monofunctional polymerizable monomer may function as a solvent.

(Λ / 4 plate)
The λ / 4 plate constituting the circularly polarizing plate is a conventionally known λ / 4 plate. When light incident on the λ / 4 plate is linearly polarized light, it is emitted as circularly polarized light and incident on the λ / 4 plate. When the light to be circularly polarized is emitted as linearly polarized light.

The λ / 4 plate is a plate having a function of converting linearly polarized light having a specific wavelength into circularly polarized light or converting circularly polarized light into linearly polarized light. More specifically, the plate has an in-plane retardation value of Re (λ) = λ / 4 (or an odd multiple thereof) at a predetermined wavelength λnm. This expression only needs to be achieved at any wavelength in the visible light range (for example, 550 nm).
The λ / 4 plate may be composed of only the optically anisotropic layer or may be configured such that the optically anisotropic layer is formed on the support, but the λ / 4 plate has the support. In some cases, the combination of support and optically anisotropic layer is intended to be a λ / 4 plate.
As the λ / 4 plate, a known λ / 4 plate can be used.

In the liquid crystal film of the present invention, the λ / 4 plate preferably has a small Rth (550) which is retardation in the thickness direction.
Specifically, Rth (550) is preferably −50 nm to 50 nm, more preferably −30 nm to 30 nm, and even more preferably Rth (λ) is zero. Thereby, a preferable result is obtained in that circularly polarized light incident obliquely on the λ / 4 plate can be converted into linearly polarized light.

Here, the λ / 4 plate is arranged with the slow axis aligned so that the other circularly polarized light that is transmitted through the cholesteric liquid crystal layer 18 and incident (circularly polarized light that is transmitted through the cholesteric liquid crystal layer) is linearly polarized light. The

(Linear polarizing plate)
The linearly polarizing plate constituting the circularly polarizing plate has a polarization axis in one direction and has a function of transmitting specific linearly polarized light.
As the linear polarizing plate, a general linear polarizing plate such as an absorption polarizing plate containing an iodine compound or a reflective polarizing plate such as a wire grid can be used. The polarization axis is synonymous with the transmission axis.
As an absorption type polarizing plate, for example, any of an iodine type polarizing plate, a dye type polarizing plate using a dichroic dye, and a polyene type polarizing plate can be used. The iodine-based polarizing plate and the dye-based polarizing plate are generally produced by adsorbing iodine or a dichroic dye to polyvinyl alcohol and stretching it.

Here, the linearly polarizing plates are arranged with their polarization axes aligned so that the linearly polarized light that is transmitted through the λ / 4 plate is transmitted. Thus, the combination of the linearly polarizing plate and the λ / 4 plate functions as a circularly polarizing plate that transmits the light incident from the λ / 4 plate side with the other circularly polarized light as linearly polarized light. In other words, the combination of the λ / 4 plate and the linearly polarizing plate transmits circularly polarized light whose direction of rotation is opposite to that of the circularly polarized light reflected by the cholesteric liquid crystal layer 18.

(Adhesive layer)
The adhesive layer is a laminate of the cholesteric liquid crystal layer 18 and the λ / 4 plate (circularly polarizing plate).
The adhesive layer can be made of various known materials as long as the target layer (sheet-like material) can be bonded together, and has fluidity when bonded. It may be a layer made of an adhesive, a gel-like (rubber-like) soft solid when pasted together, or a layer made of an adhesive that does not change the gel-like state thereafter, or an adhesive and an adhesive It may be a layer made of a material having both characteristics of an agent. Accordingly, the pressure-sensitive adhesive layer may be a known material used for laminating sheet-like materials, such as an optical transparent adhesive (OCA (Optical Clear Adhesive)), an optical transparent double-sided tape, and an ultraviolet curable resin.

[Use]
Although the use of the liquid crystal film of the present invention is not particularly limited, for example, an advertising medium pasted on a window glass as a building window advertisement, an advertising medium pasted on a window glass of a car, taxi, bus, train, etc. Design decorations, road signs, houses and stores, aquariums, zoos, botanical museums, museum windows, toys and stationery such as play machines, play cards, underlays, stage, theater equipment, elevators, escalators , Transparent materials such as stairs, fashion materials such as bags and clothes, goggles and sunglasses, materials for interior fabrics such as bags, curtains and floors, POP advertising (Point of purchase advertising), business cards, stickers, postcards, photos, coasters, Separation of tickets, fan, paper, tent, blind, shutter, protective shield, screen, etc. Home appliances (camera, instant camera, PC (personal computer), smartphone, TV, recorder, range, audio player, game machine, VR (virtual reality) headset, vacuum cleaner, washing machine), smartphone cover, plush toy, cup, Sports such as dishes, plates, baskets, vases, desks, chairs, CDs (compact discs), DVD cases, books, calendars, plastic bottles, food packaging containers, guitars, pianos and other instruments, rackets, bats, clubs, balls, etc. Attractions such as supplies, labyrinths, ferris wheels, roller coasters, haunted houses, artificial flowers, educational toys, board games, umbrellas, canes, watches, music boxes, necklaces and other clothing materials, cosmetic containers, solar panels, lights and lamp covers Can be used as

The liquid crystal film of the present invention has been described in detail above. However, the present invention is not limited to the above-described example, and various improvements and modifications may be made without departing from the gist of the present invention. It is.

Hereinafter, the features of the present invention will be described more specifically with reference to examples. The materials, reagents, used amounts, substance amounts, ratios, processing details, processing procedures, and the like shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

[Example 1]
As Example 1, a liquid crystal film was manufactured using a manufacturing apparatus 100a configured as shown in FIG.

(Preparation of liquid crystal composition)
The composition shown below was stirred and dissolved in a container kept at 25 ° C. to prepare a cholesteric liquid crystal ink liquid A (liquid crystal composition).
---------------------------------
Cholesteric liquid crystal ink A
---------------------------------
The following liquid crystal compound 1 1g
Chiral agent 1 with the following structure 107 mg
1 mg of horizontal alignment agent with the following structure
Initiator: IRGACURE 907 (BASF) 40 mg
IRGANOX1010 10mg
MEK (methyl ethyl ketone) 1.6 g
---------------------------------

(Formation of cholesteric liquid crystal layer)
As the support 12a, a 50 μm thick PET film manufactured by FUJIFILM Corporation was used. A predetermined pattern was printed in color on the back surface of the support 12a to form a pattern mask.

As the coating step, the cholesteric liquid crystal ink liquid A prepared above was coated on the surface of the support using a die coater. The coating was adjusted at a room temperature so that the thickness of the coating layer after drying was about 2 to 5 μm, and a coating film was formed.
Next, as an irradiation step, UV (ultraviolet light, wavelength 365 nm) irradiation was performed at 50 mJ / cm ² on the coating film through a pattern mask at room temperature. In addition, LEDUVHLDL-200X180-U6PSC (manufactured by CCS Co., Ltd.) was used as a light source for UV irradiation.

Next, as a heating step, the support on which the coating film after the irradiation step was laminated was heated in a hot air drying zone at 90 ° C. for 1 minute.
Next, as a curing step, UV irradiation (wavelength 300 to 350 nm, 200 mJ / cm ² ) is applied from the surface to the coated film after heat treatment at room temperature in a nitrogen atmosphere (oxygen concentration of 500 ppm or less) to cure the coated film. A cholesteric liquid crystal layer was formed.
Note that UE0961-426-05CQT (manufactured by Iwasaki Electric Co., Ltd.) was used as a light source for UV irradiation.
Then, it wound up with the winding roller.

[Example 2]
As Example 2, a liquid crystal film was manufactured using a manufacturing apparatus 100b having a configuration as shown in FIG.
Specifically, a 50 μm thick PET film manufactured by FUJIFILM Corporation is used as the support 12 b, and a predetermined pattern is formed on the base film 20 (100 μm thick PET film manufactured by Toyobo Co., Ltd.) as the mask film 14. Is printed in color to form a pattern mask (ink layer 22), the mask film 14 is adhered to the support 12b before the coating step, and the mask film 14 is peeled off after the curing step. Produced a liquid crystal film in the same manner as in Example 1.
In addition, the mask film 14 stuck the pattern mask side to the support body 12b.

[Example 3]
A liquid crystal film was produced in the same manner as in Example 2 except that the base film 20 side of the mask film 14 was adhered to the support 12b.

[Example 4]
In the irradiation process, the irradiation is performed twice, the irradiation amount in the first irradiation step is 20 mJ / cm ^2, and the irradiation amount in the second irradiation step is 40 mJ / cm ^2. A liquid crystal film was prepared.

[Example 5]
A liquid crystal film was produced in the same manner as in Example 4 except that the irradiation amount in the first irradiation step was 50 mJ / cm ² and the irradiation amount in the second irradiation step was 100 mJ / cm ² .

[Example 6]
The wavelength of the light of the first irradiation step was 385 nm, dose of the 50 mJ / cm ^2, 365 nm of the wavelength of the second irradiation step, except for using 50 mJ / cm ² irradiation amount in the same manner as in Example 4, the liquid crystal A film was prepared.

[Example 7]
A liquid crystal film was produced in the same manner as in Example 4 except that the irradiation amount in the first irradiation step was 125 mJ / cm ² and the irradiation amount in the second irradiation step was 125 mJ / cm ² .

[Example 8]
As an initiator contained in the liquid crystal composition (cholesteric liquid crystal ink liquid A), IRGACURE 369 (manufactured by BASF), 40 mg was used, except that the wavelength of light in the curing step was 365 nm. A liquid crystal film was prepared.

[Comparative Example 1]
A liquid crystal film was produced in the same manner as in Example 1 except that the irradiation step was performed after the alignment step.

[Comparative Example 2]
A liquid crystal film was produced in the same manner as in Example 1 except that a black and white binary pattern mask was formed on the support by printing as a pattern mask.

[Comparative Example 3]
A liquid crystal film was produced in the same manner as in Example 2 except that a black and white binary pattern mask was formed on the support by printing as a pattern mask.

<Evaluation>
About the liquid crystal film produced in each Example, it observed visually from the cholesteric-liquid-crystal layer side, evaluated the fineness of a pattern and the gradation of a color display, and evaluated it with the following references | standards.

Evaluation of pattern definition AA: Pretty good A: Good B: Somewhat good C: Pattern is blurred.

Evaluation of gradation of color display A: High gradation B: Slightly high gradation C: Binary or color is blurred.
The results are shown in Table 1.
Moreover, the image which image | photographed the pattern mask of Example 1 is shown in FIG. 8, and the image which image | photographed the liquid crystal film produced in Example 1 is shown in FIG. In the present invention, the same effect can be obtained even with the gray scale pattern mask shown in FIG. Further, a part of the liquid crystal film shown in FIG. 7 is cut out for evaluation.
FIG. 9 shows an image of the binary mask used in Comparative Examples 2 and 3.

As shown in Table 1, it can be seen that the liquid crystal films of Examples 1 to 8 produced by the production method of the present invention have better definition and gradation than the comparative examples.
Further, from the comparison between Example 2 and Example 3, when the pattern mask is formed on a film different from the support and is attached to the support to perform the irradiation process, the pattern mask side is It can be seen that it is preferable to stick to the support.
Further, it can be seen from the comparison between Example 1 and Examples 5 and 6 that the definition is further improved by irradiating light twice in the irradiation process.
Further, from comparison between Examples 5 and 6 and Example 7, it is understood that the total irradiation amount is preferably 200 mJ / cm ² or less.
Further, it can be seen from the comparison between Example 1 and Example 8 that the wavelength of light in the irradiation process and the wavelength of light in the curing process are preferably different.

[Example 9]
As Example 9, a liquid crystal film was produced in the same manner as in Example 1 except that the pattern mask shown in FIG. 10 was used. An image of the produced liquid crystal film is shown in FIG.
As can be seen from FIG. 10 and FIG. 11, it can be seen that regions having different colors of the cholesteric liquid crystal layer, that is, selective reflection wavelengths, are formed in accordance with the pattern and density of the pattern mask.
From the above results, the effect of the present invention is clear.

12a, 12b Support 14 Mask film 16 Circular polarizing plate 18 Cholesteric liquid crystal layer 20 Base film 21a Coating film 21b Exposed coating film 21c Oriented coating film 22 Ink layers 23a-23d, 25a-25b Laminated

film

100a, 100b Liquid crystal film Manufacturing device 102 Delivery roller 104

Coating nozzle

106, 114 Backup roller 108 Exposure device 110 Heating device 112 UV irradiation device 116 Winding roller 120 First transport unit 122 Second transport unit 124

Third transport unit

130, 132, 142, 146 Roll 140 Supply roller 144 Collection roller 150 Application unit 152 Exposure unit 154 Heating unit 156 Curing unit

Claims

A delivery step of feeding a long support in the longitudinal direction;
An application step of applying a liquid crystal composition containing a cholesteric liquid crystal compound and a photosensitive chiral agent to the support surface while transporting the fed support in the longitudinal direction;
An irradiation step of irradiating the coating film of the liquid crystal composition in an undried state with light having a wavelength at which the chiral agent is sensitive;
An alignment step of aligning liquid crystals by heating the coating film;
A curing step of curing the oriented coating film, in this order,
In the irradiation step, the coating film is irradiated with light through a pattern mask arranged on the support side,
The pattern mask is a multi-tone pattern mask having three or more regions having different transmittances with respect to light having a wavelength to which the chiral agent is sensitive.
In the irradiation step, a method of manufacturing a liquid crystal film in which light is applied to each region of the coating film by irradiating the coating film with light through the multi-tone pattern mask.
The method for producing a liquid crystal film according to claim 1, wherein the pattern mask is formed on a back surface of the support.
The pattern mask is formed on the surface of a long base film,
2. The method for producing a liquid crystal film according to claim 1, wherein in the irradiation step, light irradiation is performed in a state where the base film on which the pattern mask is formed is attached to the back surface of the support.
The method for producing a liquid crystal film according to any one of claims 1 to 3, wherein the pattern mask is formed by gray scale printing.
The irradiation step has a first irradiation step and a second irradiation step,
The method for producing a liquid crystal film according to any one of claims 1 to 4, wherein a light irradiation amount in the first irradiation step is smaller than a light irradiation amount in the second irradiation step.
The method for producing a liquid crystal film according to claim 5, wherein the total irradiation amount of the first irradiation step and the second irradiation step is 200 mJ / cm 2 or less.
The irradiation step has a first irradiation step and a second irradiation step,
The method for producing a liquid crystal film according to any one of claims 1 to 6, wherein a peak wavelength of light irradiated in the first irradiation step and a peak wavelength of light irradiated in the second irradiation step are different from each other.
The curing step is a step of photocuring the coating film,
The method for producing a liquid crystal film according to any one of claims 1 to 7, wherein a wavelength of light irradiated in the curing step is different from a wavelength of light irradiated in the irradiation step.
In the curing step, the pattern mask is integrally transported in a state of being arranged on the back side of the support,
The manufacturing method of the liquid crystal film of Claim 8 which irradiates light to the surface side on the opposite side to the said pattern mask.
The method for producing a liquid crystal film according to any one of claims 1 to 9, wherein a coating method of the liquid crystal composition in the coating step is bar coating.
A method for producing a liquid crystal film in which a combination of the coating step, the irradiation step, the alignment step, and the curing step is repeated twice or more to form two or more cholesteric liquid crystal layers,
The light irradiation is performed through the pattern mask having the same pattern in the two or more irradiation steps, and the amount of light irradiation in each of the irradiation steps is different from each other. Liquid crystal film production method.
A function having a step of attaching a circularly polarizing plate to the surface of the cured coating film or the back surface of the support after the curing step of the method for producing a liquid crystal film according to any one of claims 1 to 11. For producing a conductive film.