JP6858113B2 - Real image display member and display system - Google Patents

Description

The present invention relates to a member for displaying a real image. More specifically, the present invention relates to a real image display member that can be used as a head-up display system or a transparent screen member. The present invention also relates to a display system using the above-mentioned real image display member.

In the projected image display system, the image projected by the projector is displayed by the projected image display member. For example, in a head-up display system, which is one of the projected image display systems, a projected image display member having a combiner function capable of displaying the projected image and the landscape in front at the same time is used. Patent Document 1 discloses that a half mirror film including a retardation layer and a plurality of cholesteric liquid crystal layers is sandwiched between two resin films such as a polyvinyl butyral film to form an intermediate layer. In Patent Document 1, the above-mentioned retardation layer and cholesteric liquid crystal layer are formed by repeatedly applying and curing a liquid crystal composition containing a liquid crystal compound on a peelable support.

Japanese Patent No. 5973109 Japanese Unexamined Patent Publication No. 2015-212800

As disclosed in Patent Document 1, the projected image display member used in the conventional head-up display system uses a virtual image display. For example, the light emitted from the image display means is reflected by the projected image display member arranged on the windshield and then reaches the observer. The observer is looking at the image projected on the windshield, but since it is possible to make the image appear to be in front of and far from the windshield, application to a car navigation system or the like is being considered. On the other hand, it is considered to display a clock, a speed meter, etc. on the windshield, but in the case of such a video source, it is displayed at the position of the windshield using a real image display, not in front of and far from the windshield. Is required.

As a real image display member capable of displaying a real image, for example, Patent Document 2 describes a real image display member having a resin layer containing inorganic particles, and light from the front side of the display member is reflected. It is described that the projected image and the scene on the back side can be visually recognized at the same time by transmitting the light from the back side.

A real image display member that utilizes the scattering of inorganic particles scatters light in all directions, so that the displayed image can be visually recognized at a high angle. However, the displayed real image is dark, especially the windshield and the like. There is a problem that it cannot be applied when it is used in an in-vehicle environment where there is external light. Further, if the scattering property is increased in order to obtain a bright display, the transmittance of the real image display member itself decreases, and the legal restriction that the visible light transmittance in the vertical direction with respect to the windshield for automobiles is 70% or more is satisfied. I couldn't.

Therefore, in view of the above circumstances, it is an object of the present invention to provide a real image display member having a bright display image and excellent visibility, and a display system.

In order to solve the above problems, the present inventors have focused on using a cholesteric liquid crystal layer as a reflective layer. Furthermore, as a result of diligent studies by the present inventors, it has been found that by gently waving the orientation state of the cholesteric liquid crystal, it is possible to obtain a bright real image display at a limited angle as in an in-vehicle environment. I found that I could solve the problem.

That is, it was found that the above-mentioned problems can be achieved by the following configuration.

[1] All cholesteric liquid crystals have one or more light reflecting layers in which the central wavelength of selective reflection at a polar angle of 60 ° exists in the visible light region, and at least one of the light reflecting layers is formed from a cholesteric liquid crystal layer. A member for displaying a real image that has the same spiral sense of layers and satisfies the following equation (1).
R [-60,40] (550) / R [-60,30] (550) ≧ 1.5 Equation (1)
Here, R [-60,40] (550) is a polar angle 40 at an azimuth angle 180 ° deviated from the azimuth angle of the incident light with respect to the incident light having a polar angle of −60 ° on the real image display member. Represents the reflectance at a wavelength of 550 nm, measured at a light receiving angle of °, and R [-60,30] (550) is the incident light with respect to the incident light with a polar angle of -60 ° on the real image display member. It represents the reflectance at a wavelength of 550 nm, which is measured at a light receiving angle of a polar angle of 30 ° at an azimuth that deviates from the azimuth of.
[2] The real image display member according to [1], which has a retardation layer A composed of a λ / 2 retardation layer or a λ / 4 retardation layer.
[3] The cholesteric liquid crystal layer has a striped pattern of bright and dark areas observed by a scanning electron microscope in a cross section, and the striped pattern has a wavy structure, and the distance between peaks of the wavy structure. The real image display member according to [1] or [2], wherein the average value of the above is 0.5 μm to 50 μm.
Here, the wavy structure means that at least one region M in which the absolute value of the inclination angle with respect to the plane of the cholesteric liquid crystal layer is 5 ° or more exists in the continuous line of the bright part or the dark part of the striped pattern, and the region M is sandwiched. Represents the closest point where a peak or valley with an inclination angle of 0 ° is identified.
Further, the inter-peak distance of the wavy structure is the distance in the plane direction of the cholesteric liquid crystal layer for two peaks or valleys having an inclination angle of 0 ° at the closest positions with the region M in between, and the cholesteric liquid crystal layer is measured. The length in the long axis direction of the cross section is 100 μm, and the value is arithmetically averaged over the total thickness.
[4] The real image display member according to any one of [1] to [3], wherein the maximum reflectance of the integrated reflectance at a wavelength of 620 to 680 nm is 15 to 28%.
[5] The real image display member according to [2], which has a retardation layer B on a surface opposite to a surface of the light reflection layer having a retardation layer A.
[6] The real image display member according to [5], wherein the narrow angle formed by the slow axis of the phase difference layer A and the slow axis of the phase difference B is 40 ° to 85 °.
[7] Includes a first glass plate, a second glass plate, and an intermediate layer between the first glass plate and the second glass plate, and at least a part of the intermediate layer [1] to [6]. A real image display member including the real image display member according to any one of.
[8] The member for displaying a real image according to [7], which is a windshield glass.
[9] The real image display member according to [7] or [8], wherein the intermediate layer is a resin film.
[10] The member for displaying a real image according to [9], wherein the resin film contains polyvinyl butyral.
[11] The real image display member according to any one of [1] to [10] used as an in-vehicle display system.
[12] A projection image display system having a real image display member according to any one of [1] to [11] and a projector, and having p-polarized light in which the incident light of the projector vibrates in a direction parallel to the incident surface. ..
[13] The projection image display system according to [12], wherein the incident light is incident on the normal line of the projection image display member at an angle of 40 ° to 70 °.
[14] The projection image display system according to [12] or [13], wherein the incident light is incident from below when the projection image display member is used.

According to the present invention, it is possible to provide a real image display member having a bright display image and excellent visibility, and a display system.

FIG. 1 is a diagram schematically showing an example of a member for displaying a real image of the present invention. FIG. 2 is a diagram schematically showing an example of a laminated glass manufactured by the manufacturing method of the present invention. FIG. 3 is a diagram schematically showing a method of measuring the reflectance of the member for displaying a real image of the present invention.

Hereinafter, the present invention will be described in detail.
Hereinafter, the optical film of the present invention will be described in detail. The numerical range represented by using "~" in the present specification means a range including the numerical values before and after "~" as the lower limit value and the upper limit value.
In the present specification, for example, angles such as "45 °", "parallel", "vertical" or "orthogonal" shall differ from the exact angles within a range of less than 5 degrees unless otherwise specified. Means. The difference from the exact angle is preferably less than 4 degrees, more preferably less than 3 degrees.
As used herein, "(meth) acrylate" is used to mean "one or both of acrylate and methacrylate".
As used herein, "identical" shall include an error range generally tolerated in the art. Further, in the present specification, when the term "all", "all" or "whole surface" is used, it includes not only 100% but also an error range generally accepted in the technical field, for example, 99% or more. It shall include the case where it is 95% or more, or 90% or more.

In the present specification, the term "sense" for circularly polarized light means whether it is right-handed circularly polarized light or left-handed circularly polarized light. The sense of circular polarization is right-handed circularly polarized light when the tip of the electric field vector turns clockwise as time increases when viewed as the light travels toward you, and left-handed when it turns counterclockwise. Defined as circularly polarized.

In the present specification, the term "sense" may be used for the twisting direction of the spiral of the cholesteric liquid crystal. When the twist direction (sense) of the spiral of the cholesteric liquid crystal is right, it reflects the right circularly polarized light and transmits the left circularly polarized light, and when the sense is left, it reflects the left circularly polarized light and transmits the right circularly polarized light.

Visible light is light having a wavelength that can be seen by the human eye among electromagnetic waves, and indicates light in the wavelength range of 380 nm to 780 nm. Invisible light is light in a wavelength region of less than 380 nm or in a wavelength region 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, and light in the wavelength range of 495 nm to 570 nm is green light, which is 620 nm to 750 nm. Light in the wavelength range is red light. Of the infrared light, the near infrared light is an electromagnetic wave in the wavelength range of 780 nm to 2500 nm. Ultraviolet light is light having a wavelength in the range of 10 to 380 nm.
In the present specification, the measurement of the light intensity required in connection with the calculation of the light transmittance may be measured by using, for example, a normal visible spectrum meter and using the reference as air.
In the present specification, the term "reflected light" or "transmitted light" is used to include scattered light and diffracted light.

In the present invention, the integrated reflectance is defined as a large integrating sphere device (V-550, manufactured by JASCO Corporation) so that light is incident from the visible surface of a target object (member). It is a value measured so as to include specularly reflected light without using an optical trap using a value attached with ILV-471) manufactured by JASCO Corporation.
As for the selective reflection wavelength, when the reflection spectrum of the reflection region is measured by the above method, a waveform of characteristic reflectance which is a mountain shape (convex upward) with the wavelength as the horizontal axis can be obtained. At this time, the average reflectance (arithmetic average) of the maximum value and the minimum value of the characteristic reflectance is obtained, and the wavelength value on the short wave side of the two wavelengths of the two intersections of the waveform and the average reflectance is λA (nm) and the long wave. The value of the wavelength on the side is λB (nm), and it is a value calculated by the following formula.
Peak wavelength of characteristic reflection = (λA + λB) / 2
Further, the fact that the selective reflection wavelengths of a plurality of objects are "equal" does not mean that they are exactly equal, and an error in a range that is not optically affected is allowed. Specifically, "equal to" the selective reflection wavelengths of a plurality of objects means that the difference in selective reflection wavelengths between the objects is 20 nm or less, and this difference is preferably 15 nm or less. It is more preferably 10 nm or less.

The polarization state of each wavelength of light can be measured using a spectral radiance meter or a spectrum meter equipped with a circular polarizing plate. In this case, the intensity of the light measured through the right circular polarizing plate I _R, the intensity of the light measured through the left circular polarizing plate corresponds to I _L. It can also be measured by attaching a circular polarizing plate to an illuminometer or a spectrum meter. The ratio can be measured by attaching a right circular polarization transmission plate and measuring the amount of right circular polarization, and attaching a left circular polarization transmission plate and measuring the amount of left circular polarization.

As used herein, p-polarized light means polarized light that oscillates in a direction parallel to the plane of incidence of light. The incident surface means a surface perpendicular to a reflecting surface (such as a laminated glass surface) and containing an incident light ray and a reflected light ray. In p-polarized light, the vibration plane of the electric field vector is parallel to the entrance plane. As used herein, s-polarized light means polarized light that oscillates in a direction perpendicular to the plane of incidence of light.
As used herein, Re (550) means in-plane retardation (nm) at a wavelength of 550 nm, and Rth (550) means thickness-direction retardation (nm) at a wavelength of 550 nm. As a method for measuring Re (550) and Rth (550), it can be measured with a phase difference measuring device such as KOBRA 21ADH or WR (manufactured by Oji Measuring Instruments Co., Ltd.) or AXOSCAN (manufactured by AXOMETRICS). The measurement wavelength is 550 nm unless otherwise specified.

<< Real image display member >>
The member for displaying a real image of the present invention is
It has one or more light reflection layers in which the central wavelength of selective reflection at a polar angle of 60 ° exists in the visible light region.
Satisfy the following formula (1) and
Of the above reflective layers, at least one is formed from a cholesteric liquid crystal layer.
It is a real image display member having the same spiral sense of all cholesteric liquid crystal layers.
R [-60,40] (550) / R [-60,30] (550) ≧ 1.5 Equation (1)
Here, R [-60,40] (550) is a polar angle of 40 ° at an azimuth 180 ° deviated from the azimuth of the incident light with respect to the incident light having a polar angle of −60 ° on the display member. Represents the reflectance at a wavelength of 550 nm, which is measured by the light receiving angle of, and R [-60,30] (550) is the azimuth of the incident light with respect to the incident light having a polar angle of -60 ° to the display member. It represents the reflectance at a wavelength of 550 nm, measured at a light receiving angle of a polar angle of 30 ° at an azimuth angle 180 ° off the angle.

The real image display member of the present invention may include a support, a retardation layer, and an alignment film. FIG. 1 schematically shows an example of a member for displaying a real image of the present invention. In the real image display member of the present invention, the light reflecting layer 1 includes at least one cholesteric liquid crystal layer, and the alignment layer 2 may be included for the purpose of adjusting the orientation of the cholesteric liquid crystal. The real image display member of the present invention may include the retardation layer 3 and the retardation layer 5, and may include the alignment layer 2 for the purpose of adjusting the orientation of the retardation layer 3 and the retardation layer 5. Further, although not shown in FIG. 1, a member for displaying a real image of the present invention may be produced by using a peelable support.

The real image display member includes a retardation layer and a light reflecting layer including a cholesteric liquid crystal structure. By providing the real image display member in the intermediate layer of the laminated glass, for example, in a head-up display system, the projected image display portion can be formed on a glass plate or a laminated glass.
Hereinafter, the glass plate or laminated glass may be collectively referred to as a glass plate or glass.

In the present specification, the projected image display portion may be a portion capable of displaying the projected image with reflected light, and may be a portion capable of visually displaying the projected image projected from a projector or the like.
When the glass plate is used in the real image display system, the image projected from the projector can be visually displayed at the part of the functional layer, and when the functional layer is observed from the same surface side on which the image is displayed, Information or landscape on the opposite side can be observed at the same time.

In the embodiment in which the real image display member is used by being attached to the glass plate, it may be on the entire surface of the glass plate or may be a part of the entire area of the glass plate. If it is a part, the area may be 90% or less, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, 5% or less, etc. with respect to the total area of the glass plate. It may be 1% or more, 3% or more, 5% or more, 7% or more, and 10% or more. Further, in the case of a part, the real image display member may be provided at any position on the glass plate, but when used as a head-up display system, the image is easily visible to the observer (for example, the driver). Is preferably provided as shown. For example, the position where the functional layer is provided may be determined from the relationship between the position of the driver's seat of the applied vehicle and the position where the projector is installed. Specifically, in a video source that is preferably arranged at an angle that the driver looks down on, it is preferably arranged below the center of the glass plate.

In the glass plate, the member for displaying the real image may be a flat surface having no curved surface, but may have a curved surface, and has a concave or convex shape as a whole to enlarge the projected image. Alternatively, it may be displayed in a reduced size.
The thickness of the real image display member is 200 μm or less, preferably 150 μm or less, more preferably 130 μm or less, and further preferably 120 μm or less. In the aspect without a support, it is preferably 20 μm or less, more preferably 15 μm or less.

The real image display member may have at least a function as a half mirror with respect to the projected light. However, it does not need to function as a half mirror for light in the entire visible light region, for example. Further, the real image display unit may have the above-mentioned function for light at at least a part of the incident angles.

In the embodiment in which the real image display member is used by being attached to a glass plate, the real image display member preferably has visible light transmission in order to enable observation of information or a landscape on the opposite surface side. The real image display unit may have a light transmittance of 40% or more, preferably 50% or more, more preferably 60% or more, still more preferably 70% or more in the wavelength range of visible light. If the visible light transmittance is 70% or more, it can be arbitrarily used in the entire area of the windshield for automobiles. The light transmittance is the light transmittance obtained by the method described in JIS-K7105.

The real image display member may include a layer containing a cholesteric liquid crystal structure and a layer such as a retardation layer, an alignment layer, an adhesive layer, a base layer, and a transparent layer.
The real image display member used for laminating glass or producing laminated glass may be in the form of a film, a sheet, or a plate. The real image display member may be formed as a thin film in a roll shape or the like, and then used for glass bonding or production of laminated glass.

[Layer containing cholesteric liquid crystal structure]
In the real image display member, one or two or more layers including the cholesteric liquid crystal structure may be contained. Other layers such as an alignment layer and an adhesive layer may be included between the layers containing two or more cholesteric liquid crystal structures. Further, another layer such as a base layer or a transparent layer may be included between the layer containing the cholesteric liquid crystal structure and the retardation layer.

(Cholesteric liquid crystal structure)
The cholesteric liquid crystal structure may be a structure in which the orientation of the liquid crystal compound that is the cholesteric liquid crystal phase is maintained, and typically, the polymerizable liquid crystal compound is placed in the orientation state of the cholesteric liquid crystal phase and then irradiated with ultraviolet rays. The structure may be such that the structure is polymerized and cured by heating or the like to be in a state of no fluidity, and at the same time, the orientation form is not changed by an external field or an external force. In the cholesteric liquid crystal structure, it is sufficient that the optical properties of the cholesteric liquid crystal phase are maintained, and the liquid crystal compound does not have to exhibit liquid crystal properties anymore. For example, the polymerizable liquid crystal compound may lose its liquid crystal property due to its high molecular weight due to the curing reaction.

It is known that the cholesteric liquid crystal phase selectively reflects circularly polarized light of either right-handed or left-handed circularly polarized light and transmits circularly polarized light of the other sense. In the present specification, the circularly polarized light selective reflection may be simply referred to as a selective reflection.
As a film containing a layer in which a cholesteric liquid crystal phase exhibiting circularly polarized selective reflectivity is fixed, many films formed from a composition containing a polymerizable liquid crystal compound have been conventionally known, and the cholesteric liquid crystal structure or the cholesteric liquid crystal layer has been known. , Those prior arts can be referred to.

The central wavelength λ of the selective reflection of the cholesteric liquid crystal structure depends on the pitch P (= spiral period) of the spiral structure in the cholesteric phase, and follows the relationship between the average refractive index n and λ = n × P of the cholesteric liquid crystal structure. In the present specification, the central wavelength λ of selective reflection of the cholesteric liquid crystal structure means the wavelength at the center of gravity of the reflection peak of the circularly polarized reflection spectrum measured from the normal direction of the cholesteric liquid crystal layer.

As can be seen from the above relationship of λ = n × P, the center wavelength of selective reflection can be adjusted by adjusting the pitch of the spiral structure. The cholesteric liquid crystal layer exhibiting selective reflection in the visible light region preferably has a central wavelength of selective reflection in the visible light region. Adjust the n-value and P-value to adjust the center wavelength λ, for example, to selectively reflect either right-handed or left-handed circular polarization to red, green, or blue light. be able to.

In the real image display member of the present invention, a clear double image as in the mode using a virtual image does not occur, but diffuse reflection occurs when the light reflected on the front surface or the back surface re-enters the real image display member. As a result, image blurring occurs and the sharpness decreases. Therefore, in a mode such as a head-up display system in which the projected light is attached to a glass plate and used, a cholesteric liquid crystal structure is used to reduce image blur caused by reflection of projected light on the front surface or the back surface of the glass plate. It is preferable that the glass plate is used so that the light is obliquely incident on the containing layer. Further, when the light is obliquely incident in this way, the center wavelength of the selective reflection is shifted to the short wavelength side. Therefore, it is possible to adjust n × P so that λ calculated according to the above equation of λ = n × P is on the long wavelength side with respect to the wavelength of selective reflection required for displaying the projected image. preferable. The center of the selective reflection when a ray relative to the normal direction (helical axis of the cholesteric liquid crystal layer) of the layer containing a cholesteric liquid crystal structure with a layer containing a cholesteric liquid crystal structure of the refractive index n ₂ is passed at an angle theta ₂ When the wavelength is λ _d , λ _d is expressed by the following equation.
λ _d = n ₂ × P × cos θ ₂

For example, when a cholesteric liquid crystal layer and a phase difference A having a λ / 2 phase difference are used as the layer containing the cholesteric liquid crystal structure, the angle is 45 ° to 70 ° with respect to the normal of the projected image display portion in the air having a refractive index of 1. Light incident from the phase difference A side having a λ / 2 phase difference usually has a λ / 2 phase difference layer having a refractive index of about 1.45 to 1.80 and is 23 ° to 40 with respect to the normal of the projected image display portion. It transmits at an angle of ° and is incident on the cholesteric liquid crystal layer having a refractive index of about 1.61. Since light is transmitted at an angle of 26 ° to 36 ° in the cholesteric liquid crystal layer, this angle and the center wavelength of the desired selective reflection may be inserted into the above equation to adjust n × P.
Since the pitch of the cholesteric liquid crystal phase depends on the type of chiral auxiliary used together with the polymerizable liquid crystal compound or the concentration thereof added, a desired pitch can be obtained by adjusting these. For the measurement method of spiral sense and pitch, use the method described in "Introduction to Liquid Crystal Chemistry Experiment", edited by Liquid Crystal Society of Japan, Sigma Publishing, 2007, p. 46, and "Liquid Crystal Handbook", Liquid Crystal Handbook Editorial Committee, Maruzen, p. 196. be able to.

By adjusting the center wavelength of the selective reflection of the layer containing the cholesteric liquid crystal structure to be used according to the emission wavelength range of the light source used for projection and the usage mode of the layer containing the cholesteric liquid crystal structure, the light can be used efficiently and the image is clearly projected. The image can be displayed. In particular, by adjusting the center wavelength of the selective reflection of each cholesteric liquid crystal structure according to the emission wavelength range of the light source used for projection, it is possible to display a clear color projected image with high light utilization efficiency. Examples of the usage mode of the layer including the cholesteric liquid crystal structure include the angle of incidence of the projected light on the layer including the cholesteric liquid crystal structure, the direction of observing the projected image, and the like.

As the cholesteric liquid crystal structure, a cholesteric liquid crystal layer having a spiral sense of either right or left is used. The sense of reflected circularly polarized light of the cholesteric liquid crystal structure matches the sense of spiral. The spiral senses of the cholesteric liquid crystal structures having different central wavelengths of selective reflection may be the same or may contain different ones, but they are preferably the same.

The full width at half maximum Δλ (nm) of the selective reflection band indicating selective reflection depends on the birefringence Δn of the liquid crystal compound and the pitch P, and follows the relationship of Δλ = Δn × P. Therefore, the width of the selective reflection band can be controlled by adjusting Δn. Δn can be adjusted by adjusting the type and mixing ratio of the polymerizable liquid crystal compound, or by controlling the temperature at the time of fixing the orientation.
The full width at half maximum Δλ of the selective reflection may be 15 nm to 200 nm, 15 nm to 150 nm, 20 nm to 100 nm, or the like.

The cholesteric liquid crystal layer used in the present invention is preferably one in which a liquid crystal compound is fixed in a cholesteric orientation state. The cholesteric orientation state may include both an orientation state that reflects right circularly polarized light and an orientation state that reflects left circularly polarized light. The liquid crystal compound used in the present invention is not particularly limited, and various known ones can be used.

Further, the cholesteric liquid crystal layer used in the present invention preferably has a striped pattern of bright and dark areas when the cross section is observed using a scanning electron microscope (SEM).
The striped pattern preferably has a wavy structure, and the average value of the inter-peak distances of the wavy structure is preferably 0.5 μm to 50 μm. It is more preferably 1.5 μm to 30 μm, and even more preferably 2.5 μm to 20 μm.

In the present invention, the wavy structure includes at least one region M in which the absolute value of the inclination angle with respect to the plane of the cholesteric liquid crystal layer is 5 ° or more in the continuous line of the bright part or the dark part of the striped pattern. It means that two peaks or valleys with an inclination angle of 0 ° are identified at the closest positions.

A peak or valley with an inclination angle of 0 ° includes convex and concave points, but if the inclination angle is 0 °, it also includes steps and shelves. In the wavy structure, it is preferable that a region M in which the absolute value of the inclination angle is 5 ° or more and a plurality of peaks or valleys sandwiching the region M are repeated in a continuous line of bright or dark striped areas.

Further, the inter-peak distance of the wavy structure is the distance in the plane direction of the cholesteric liquid crystal layer for two peaks or valleys having an inclination angle of 0 ° at the closest positions with the region M in between, and the cholesteric liquid crystal layer is measured. It is a value calculated by arithmetic mean for a length of 100 μm in the long axis direction of the cross section and a total film thickness.

Here, if each continuous line is in contact with either of the interfaces of the film and is interrupted, both ends of the interrupted portion are not regarded as peaks or valleys. Further, when each continuous line has a bent structure as shown in FIG. 2, the continuous line is regarded as being interrupted there, and both ends thereof are not regarded as peaks or valleys.

(Method of manufacturing cholesteric liquid crystal structure)
Hereinafter, a material and a method for producing the cholesteric liquid crystal structure will be described.
Examples of the material used for forming the cholesteric liquid crystal structure include a liquid crystal composition containing a polymerizable liquid crystal compound and a chiral agent (optically active compound). If necessary, the liquid crystal composition further mixed with a surfactant, a polymerization initiator, etc. and dissolved in a solvent or the like is applied or dropped on the underlying retardation layer, base layer, cholesteric liquid crystal layer, etc., and cholesteric. After orientation aging, the liquid crystal composition can be fixed by curing to form a cholesteric liquid crystal structure. A cholesteric liquid crystal layer can be produced depending on the coating, and a layer containing a plurality of cholesteric liquid crystal dots can be produced by dripping.

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

The polymerizable liquid crystal compound is 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, and an unsaturated polymerizable group is preferable, and an ethylenically unsaturated polymerizable group is particularly preferable. The polymerizable group can be introduced into the molecule of the liquid crystal compound by various methods. The number of polymerizable groups contained in the polymerizable liquid crystal compound is preferably 1 to 6 in one molecule, and more preferably 1 to 3. Examples of polymerizable liquid crystal compounds include Makromol. Chem. , 190, 2255 (1989), Advanced Materials 5, 107 (1993), U.S. Pat. Nos. 4,683,327, 562,648, 5770107, International Publication WO 95/22586, International. Published WO95 / 24455, WO97 / 00600, WO98 / 23580, WO98 / 52905, Japanese Patent Application Laid-Open No. 1-272551, Japanese Patent Application Laid-Open No. 6-16616, Japanese Patent Application Laid-Open No. 7-110469, Japanese Patent Application Laid-Open No. 11-8801, Japanese Patent Application Laid-Open No. 2001- Includes compounds described in 328973, WO2016 / 194327, WO2016 / 052367 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 orientation temperature may be lowered.

The amount of the polymerizable liquid crystal compound added to the liquid crystal composition is preferably 80 to 99.9% by mass, preferably 85 to 99% by mass, based on the solid content mass (mass excluding the solvent) of the liquid crystal composition. It is more preferably 5.5% by mass, and particularly preferably 90 to 99% by mass.

(Chiral agent: optically active compound)
The chiral agent has the function of inducing the helical structure of the cholesteric liquid crystal phase. Since the chiral compound has a different sense of spiral or spiral pitch to be induced depending on the compound, it may be selected according to the purpose.
The chiral agent is not particularly limited, and known compounds can be used. Examples of chiral agents include Liquid Crystal Device Handbook (Chapter 3, 4-3, TN, Chiral Auxiliary for STN, page 199, Japan Society for the Promotion of Science 142, 1989), Japanese Patent Application Laid-Open No. 2003-287623, Japan. Examples thereof include the compounds described in JP-A-2002-302487, JP-A-2002-80478, JP-A-2002-80851, JP-A-2010-181852, or JP-A-2014-034581.

The chiral agent generally contains an asymmetric carbon atom, but an axial asymmetric compound or a surface asymmetric compound that does not contain an asymmetric carbon atom can also be used as the chiral agent. Examples of axially asymmetric or surface asymmetric compounds 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, the repeating unit derived from the polymerizable liquid crystal compound and the repeating unit derived from the chiral agent are derived by the polymerization reaction between the polymerizable chiral agent and the polymerizable liquid crystal compound. Polymers with repeating units can be formed. In this aspect, the polymerizable group of the polymerizable chiral agent is preferably a group of the same type as the polymerizable group of the polymerizable liquid crystal compound. Therefore, the polymerizable group of the chiral agent is preferably an unsaturated polymerizable group, an epoxy group or an aziridinyl group, more preferably an unsaturated polymerizable group, and preferably an ethylenically unsaturated polymerizable group. Especially preferable.
Moreover, the chiral agent may be a liquid crystal compound.

As the chiral agent, an isosorbide derivative, an isomannide derivative, or a binaphthyl derivative can be preferably used. As the isosorbide derivative, a commercially available product such as LC-756 manufactured by BASF may be used.
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)
The liquid crystal composition preferably contains a polymerization initiator. In the embodiment in which the polymerization reaction is allowed to proceed by irradiation with ultraviolet rays, the polymerization initiator used is preferably a photopolymerization initiator capable of initiating the polymerization reaction by irradiation with ultraviolet rays. Examples of photopolymerization initiators include α-carbonyl compounds (described in US Pat. Nos. 2,376,661 and 236,670), acidoin ethers (described in US Pat. No. 2,448,828), and α-hydrogen-substituted fragrances. Group acidoine compounds (described in US Pat. No. 2722512), polynuclear quinone compounds (described in US Pat. Nos. 3,043127 and 2951758), combinations of triarylimidazole dimers and p-aminophenyl ketone (US Pat. No. 3549367), aclysine and phenazine compounds (Japanese Patent Laid-Open No. 60-105667, US Pat. No. 4,239,850), acylphosphine oxide compounds (Japanese Patent Publication No. 63-40799, Japanese Patent Publication No. 63-40799) 29234, 10-95788, 10-29997, 2001-233842, 2000-80068, 2006-342166, 2013-14249 Japanese Patent Application Laid-Open No. 2014-137466, Japanese Patent No. 4223071, Japanese Patent Application Laid-Open No. 2010-262028, Japanese Patent Application Laid-Open No. 2014-500852), oxime compounds (Japanese Patent Laid-Open No. 2000-66385, Japanese Patent No. 4445667) (Description), and oxadiazole compounds (described in US Pat. No. 4,212,970) and the like. For example, the description in paragraphs 0500 to 0547 of JP2012-208494A can also be taken into consideration.

It is also preferable to use an acylphosphine oxide compound or an oxime compound as the polymerization initiator.
As the acylphosphine oxide compound, for example, a commercially available IRGACURE810 (compound name: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide) manufactured by BASF Japan Ltd. can be used. Examples of the oxime compound include IRGACURE OXE01 (manufactured by BASF), IRGACURE OXE02 (manufactured by BASF), TR-PBG-304 (manufactured by Joshu Powerful Electronics New Materials Co., Ltd.), ADEKA ARCULS NCI-831, and ADEKA ARCULS NCI-930. Commercially available products such as (manufactured by ADEKA) and ADEKA Arkuru's NCI-831 (manufactured by ADEKA) can be used.
Only one type of polymerization initiator may be used, or two or more types may be used in combination.
The content of the photopolymerization initiator in the liquid crystal composition is preferably 0.1% by mass to 20% by mass, preferably 0.5% by mass to 5% by mass, based on the content of the polymerizable liquid crystal compound. Is even more preferable.

(Crosslinking agent)
The liquid crystal composition may optionally contain a cross-linking agent in order to improve the film strength and durability after curing. As the cross-linking agent, one that cures with ultraviolet rays, heat, humidity or the like can be preferably used.
The cross-linking agent is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a polyfunctional acrylate compound such as trimethylolpropane tri (meth) acrylate or pentaerythritol tri (meth) acrylate; glycidyl (meth) acrylate. , Epoxy compounds such as ethylene glycol diglycidyl ether; 2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], azilysin compounds such as 4,4-bis (ethyleneiminocarbonylamino) diphenylmethane; hexa Isocyanate compounds such as methylenediisocyanate and biuret-type isocyanate; polyoxazoline compounds having an oxazoline group in the side chain; alkoxysilane compounds such as vinyltrimethoxysilane and N- (2-aminoethyl) 3-aminopropyltrimethoxysilane. Be done. Further, a known catalyst can be used depending on the reactivity of the cross-linking agent, and the productivity can be improved in addition to the improvement of the film strength and durability. These may be used alone or in combination of two or more.
The content of the cross-linking agent is preferably 3% by mass to 20% by mass, more preferably 5% by mass to 15% by mass. By setting the content of the cross-linking agent to 3% by mass or more, the effect of improving the cross-linking density can be obtained, and by setting the content of the cross-linking agent to 20% by mass or less, the stability of the cholesteric liquid crystal structure is lowered. Can be prevented.

(Orientation control agent)
An orientation control agent may be added to the liquid crystal composition that contributes to a stable or rapid planar orientation cholesteric liquid crystal structure. Examples of the orientation control agent include the fluorine (meth) acrylate-based polymers described in paragraphs [0018] to [0043] of JP-A-2007-272185, and paragraphs [0031] to [0034] of JP-A-2012-203237. ] And the like, and examples thereof include compounds represented by the formulas (I) to (IV) described in.
As the orientation control agent, one type may be used alone, or two or more types may be used in combination.

The amount of the orientation control agent added to the liquid crystal composition is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 5% by mass, and 0, based on the total mass of the polymerizable liquid crystal compound. 0.02% by mass to 1% by mass is particularly preferable.

(Surfactant)
The liquid crystal composition may contain a surfactant. The surfactant is preferably a compound that can function as an orientation control agent that contributes to a stable or rapid planar orientation cholesteric structure. Examples of the surfactant include silicone-based surfactants and fluorine-based surfactants, and fluorine-based surfactants are preferable.

Specific examples of the surfactant include the compounds described in Japanese Patent Application Laid-Open No. 2014-119605 [0083] to [0090], and the compounds described in paragraphs [0031] to [0034] of JP2012-203237A. Examples of the compounds exemplified in JP-A-2005-999248 [0092] and [093], and exemplified in JP-A-2002-129162, [0076] to [0078] and [0083] to [0085]. Examples thereof include the fluorine (meth) acrylate-based polymers described in paragraphs [0018] to [0043] of JP-A-2007-272185.

As the horizontal alignment agent, one type may be used alone, or two or more types may be used in combination.

As the fluorine-based surfactant, the compound represented by the following general formula (I) described in [2002] to [0090] of JP-A-2014-119605 is particularly preferable.

In the general formula (I), L ¹¹ , L ¹² , L ¹³ , L ¹⁴ , L ¹⁵ and L ¹⁶ are independently single-bonded, -O-, -S-, -CO-, -COO-,-, respectively. It represents OCO-, -COS-, -SCO-, -NRCO-, -CONR- (R in the general formula (I) represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms). -NRCO- and -CONR- have the effect of reducing the solubility, and the haze tends to increase during dot formation. Therefore, it is preferably -O-, -S-, -CO-, -COO-, -OCO-, -COS-, and -SCO-, and more preferably -O-, from the viewpoint of compound stability. -CO-, -COO-, and -OCO-. The alkyl group that R can take may be linear or branched. The number of carbon atoms is more preferably 1 to 3, and methyl group, ethyl group, and n-propyl group can be exemplified.

Sp ¹¹ , Sp ¹² , Sp ¹³ and Sp ¹⁴ each independently represent a single bond or an alkylene group having 1 to 10 carbon atoms, more preferably a single bond or an alkylene group having 1 to 7 carbon atoms, and even more preferably. Is a single bond or an alkylene group having 1 to 4 carbon atoms. However, the hydrogen atom of the alkylene group may be substituted with a fluorine atom. The alkylene group may or may not have branches, but a straight chain alkylene group having no branches is preferable. From a synthetic point of view, it is preferable that ^{Sp 11} and Sp ¹⁴ are the same, and Sp ¹² and Sp ^{13 are the same.}

A ¹¹ and A ¹² are 1- to tetravalent aromatic hydrocarbon groups. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 22, more preferably 6 to 14, further preferably 6 to 10, and particularly preferably 6. The aromatic hydrocarbon groups represented by ^{A 11} and A ^{12 may have a substituent.} Examples of such a substituent include an alkyl group having 1 to 8 carbon atoms, an alkoxy group, a halogen atom, a cyano group or an ester group. For the description and preferred ranges of these groups, reference can be made to the corresponding description of the T ¹¹ below. Examples of the substituent on the aromatic hydrocarbon group represented by A ¹¹ and A ¹² include a methyl group, an ethyl group, a methoxy group, an ethoxy group, a bromine atom, a chlorine atom and a cyano group. Molecules having many perfluoroalkyl moiety in the molecule, it is possible to align the liquid crystal in a small amount, since the lead to haze reduction, A ^11, A ¹² to have much a perfluoroalkyl group in the molecule It is preferably tetravalent. From a synthetic point of view, it is preferable that ^{A 11} and A ^{12 are the same.}

T ¹¹ represents the following divalent group or divalent aromatic heterocyclic group ( ^{X contained in the above T 11} is an alkyl group having 1 to 8 carbon atoms, an alkoxy group, a halogen atom, or a cyano group. Alternatively, it represents an ester group, and Ya, Yb, Yc, and Yd each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)

Among them, more preferable groups are shown below.

More preferably, it is the following group.

Most preferably, it is the following group.

The ^{number of carbon atoms of the alkyl group that X contained in T 11} can take is 1 to 8, preferably 1 to 5, and more preferably 1 to 3. The alkyl group may be linear, branched, or cyclic, and is preferably linear or branched. Examples of preferable alkyl groups include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Of these, a methyl group is preferable.

The alkyl moiety of the alkoxy group can take X contained in the T ^11, reference may be made to the described preferred range of the alkyl group X can take contained in the T ^11. Examples of the ^{halogen atom that X contained in T 11} can take include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a chlorine atom or a bromine atom is preferable. As the ester group that X contained in ^{T 11 can take, a group represented by Ra} COO − can be exemplified. Examples of ^Ra include an alkyl group having 1 to 8 carbon atoms. For the description and preferred range of the alkyl group that ^{Ra can take, the description and preferred range of the alkyl group that X contained in T 11} can take can be referred to. Specific examples of the ester include CH ₃ COO- and C ₂ H ₅ COO-. The alkyl groups having 1 to 4 carbon atoms that can be taken by Ya, Yb, Yc, and Yd may be linear or branched. For example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group and the like can be exemplified.

The divalent aromatic heterocyclic group preferably has a 5-membered, 6-membered or 7-membered heterocycle. A 5-membered ring or a 6-membered ring is more preferable, and a 6-membered ring is most preferable. As the complex atom constituting the heterocycle, a nitrogen atom, an oxygen atom or a sulfur atom is preferable. The heterocycle is preferably an aromatic heterocycle. Aromatic heterocycles are generally unsaturated heterocycles. Unsaturated heterocycles with the most double bonds are more preferred. Examples of heterocycles include furan ring, thiophene ring, pyrrole ring, pyrrolin ring, pyrrolidine ring, oxazole ring, isooxazole ring, thiazole ring, isothiazole ring, imidazole ring, imidazoline ring, imidazolidine ring, pyrazole ring, pyrazoline. Rings, pyrazolidine rings, triazole rings, flazan rings, tetrazole rings, pyran rings, thiyne rings, pyridine rings, piperazine rings, oxazine rings, morpholin rings, thiazine rings, pyridazine rings, pyrimidine rings, pyrazine rings, piperazine rings and triazine rings included. The divalent heterocyclic group may have a substituent. For a description and preferred range of examples of such substituents, the description and description of possible substituents of the 1- to tetravalent aromatic hydrocarbons ^{A 11} and A ^{12 above can be referred to.}

Hb ¹¹ represents a perfluoroalkyl group having 2 to 30 carbon atoms, more preferably a perfluoroalkyl group having 3 to 20 carbon atoms, and further preferably a perfluoroalkyl group having 3 to 10 carbon atoms. The perfluoroalkyl group may be linear, branched or cyclic, but linear or branched is preferable, and linear is more preferable.

m11 and n11 are independently 0 to 3, and m11 + n11 ≧ 1. At this time, the structures in the parentheses that exist in plurality may be the same or different from each other, but it is preferable that they are the same. General formula (I) m11, and n11 ^are determined by the ^{A 11,} and the valence of ^{A 12,} the preferred range is also the ^{A 11,} and determined by the valence of the preferred range of ^{A 12.}

The ^{o and p contained in T 11} are independently integers of 0 or more, and when o and p are 2 or more, a plurality of X's may be the same or different from each other. The ^{o contained in T 11} is preferably 1 or 2. The ^{p contained in T 11} is preferably an integer of 1 to 4, more preferably 1 or 2.

The compound represented by the general formula (I) may have a molecular structure having symmetry or may not have symmetry. The symmetry here means at least one of point symmetry, line symmetry, and rotational symmetry, and asymmetry does not correspond to any of point symmetry, line symmetry, and rotational symmetry. Means things.

The compounds represented by the general formula (I) include the above-mentioned perfluoroalkyl group (Hb ¹¹ ), linking group-(-Sp ^11- L ^{11- Sp 12-} L ¹² ) m11-A ^11- L ¹³ -and. ^{-L 14 -A 12 - (L 15} -Sp 13 -L 16 -Sp 14 -) n11-, and preferably a compound which is a combination of ^{T 11} is a divalent group having the excluded volume effect. The two perfluoroalkyl groups (Hb ¹¹ ) present in the molecule are preferably the same as each other, and the linking group- (-Sp ^11- L ^{11- Sp 12-} L ¹² ) m11-A ^{11 present in the molecule.} It is preferable that −L ¹³ − and −L ¹⁴ −A ¹² − (L ¹⁵ − Sp ^{13 −} L ¹⁶ − Sp ¹⁴ −) n11 − are also the same as each other. End of ^{Hb 11 -Sp 11 -L 11 -Sp 12} - and ^-Sp 13 ^-L 16 ^-Sp 14 ^{-Hb 11} is preferably a group represented by any one of formulas below.
(C _a F _{2a + 1} )-(C _b H _2b )-(C _a F _{2a + 1)} -(C _b H _2b ) -O- (C _r H _2r )-(C _a F _{2a + 1} )-(C _b H _2b ) -COO- _{(C r H 2r)} -
_{(C a F 2a + 1)} - (C b H 2b) -OCO- (C r H 2r) -

In the above formula, a is preferably 2 to 30, more preferably 3 to 20, and even more preferably 3 to 10. b is preferably 0 to 20, more preferably 0 to 10, and even more preferably 0 to 5. a + b is 3 to 30. r is preferably 1 to 10, more preferably 1 to 4.

In general formula ^Hb end of ^{(I) 11 -Sp 11 -L 11} -Sp 12 -L 12 - and ^{-L 15 -Sp 13 -L 16 -Sp 14} -Hb 11 is one of the following general formula The group represented by is preferable.
(C _a F _{2a + 1} )-(C _b H _2b ) -O- (C _a F _{2a + 1} )-(C _b H _2b ) -COO- (C _a F _{2a + 1} )-(C _b H _2b ) -O- (C _r H _2r ) -O- (C _a F _{2a + 1} )-(C _b H _2b ) -COO- (C _r H _2r ) -COO- (C _a F _{2a + 1} )-(C _b H _2b ) -OCO- (C _r H _2r ) -COO- The definitions of a, b, and r in the above equation are the same as the definitions directly above.

The amount of the surfactant added to the liquid crystal composition is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 5% by mass, and 0, based on the total mass of the polymerizable liquid crystal compound. 0.02% by mass to 1% by mass is particularly preferable.

(Other additives)
In addition, the liquid crystal composition may contain at least one selected from various additives such as polymerizable monomers. Further, if necessary, a polymerization inhibitor, an antioxidant, an ultraviolet absorber, a light stabilizer, a coloring material, metal oxide fine particles, etc. are added to the liquid crystal composition within a range that does not deteriorate the optical performance. can do.

In the cholesteric liquid crystal structure, a liquid crystal composition obtained by dissolving a polymerizable liquid crystal compound, a chiral agent, a polymerization initiator, and a surfactant added as needed in a solvent is added to a retardation layer, an underlayer, or first. The cholesteric liquid crystal layer or the like is coated or drip-dried and dried to obtain a coating film, and the coating film is irradiated with active light to polymerize the cholesteric liquid crystal composition to fix the cholesteric regularity. A cholesteric liquid crystal structure can be formed. The laminated film composed of a plurality of cholesteric liquid crystal layers can be formed by repeating the above-mentioned manufacturing process of the cholesteric liquid crystal layer.

(solvent)
The solvent used for preparing the liquid crystal composition is not particularly limited and may be appropriately selected depending on the intended purpose, but an organic solvent is preferably used.
The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. For example, ketones, alkyl halides, amides, sulfoxides, heterocyclic compounds, hydrocarbons, esters, ethers, etc. Can be mentioned. These may be used alone or in combination of two or more. Among these, ketones are particularly preferable in consideration of the burden on the environment.

(Coating, orientation, polymerization)
The method for applying the liquid crystal composition is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a wire bar coating method, a curtain coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die. Examples include a coating method, a spin coating method, a dip coating method, a spray coating method, and a slide coating method. It can also be carried out by transferring the liquid crystal composition separately coated on the support. It is also possible to drip the liquid crystal composition. As the dot-dotting method, an inkjet method can be used.
The liquid crystal molecules are oriented by heating the applied or drip-dropped liquid crystal composition. The heating temperature is preferably 200 ° C. or lower, more preferably 130 ° C. or lower. By this orientation treatment, a structure is obtained in which the polymerizable liquid crystal compound is twist-oriented so as to have a spiral axis in a direction substantially perpendicular to the film surface.

The liquid crystal composition can be cured by further polymerizing the oriented liquid crystal compound. The polymerization may be either thermal polymerization or photopolymerization using light irradiation, but photopolymerization is preferable. It is preferable to use ultraviolet rays for light irradiation. The irradiation energy is ^{preferably 20mJ / cm 2 ~50J / cm 2} , 100mJ / cm 2 ~1,500mJ / cm 2 is more preferable. In order to promote the photopolymerization reaction, light irradiation may be carried out under heating conditions or a nitrogen atmosphere. The irradiation ultraviolet wavelength is preferably 350 nm to 430 nm. From the viewpoint of stability, the polymerization reaction rate is preferably high, preferably 70% or more, and more preferably 80% or more. The polymerization reaction rate can be determined by measuring the consumption ratio of the polymerizable functional group using an IR absorption spectrum.

[Cholesteric liquid crystal layer]
In the present specification, the cholesteric liquid crystal layer means a layer in which the cholesteric liquid crystal phase is fixed. The cholesteric liquid crystal layer means a layer in which a cholesteric liquid crystal structure is continuously formed in layers, and is a layer exhibiting substantially the same optical characteristics at any position of the layer.
For the functional layer including the cholesteric liquid crystal layer and the plurality of cholesteric liquid crystal layers, the description of the cholesteric liquid crystal layer and the reflective layer in WO2016 / 052367 can be referred to.

The real image display member may include two or more cholesteric liquid crystal layers, and may include, for example, two layers, three layers, and four layers of cholesteric liquid crystal layers. In particular, it is preferable to include two cholesteric liquid crystal layers. For example, by using a cholesteric liquid crystal layer which is a broadband selective reflection layer that exhibits selective reflection in the red wavelength region and the green wavelength region, or the green wavelength region and the blue wavelength region, full-color display is also realized by the two cholesteric liquid crystal layers. be able to.

In the embodiment in which the real image display member includes a retardation layer, it is preferable that the cholesteric liquid crystal layer is directly provided on another layer. An alignment layer obtained by applying and curing a non-liquid crystal composition containing a (meth) acrylate monomer is provided on the surface of the retardation layer, and one of the cholesteric liquid crystal layers is formed on the surface of the alignment layer. It is possible to provide a laminated glass product capable of manufacturing a laminated glass product or a laminated glass that functions as a member for displaying a projected image.
When a cholesteric liquid crystal layer is formed on the surface of the alignment layer, the in-plane orientation of the liquid crystal in contact with the alignment layer becomes random depending on the physical properties of the alignment layer. Therefore, the cholesteric liquid crystal layer formed by applying the liquid crystal composition to the surface of the alignment layer can be a layer having an orientation defect. Then, when the cholesteric liquid crystal layer is formed on the liquid crystal layer having the orientation defect, the layer having the orientation defect can be formed in the same manner. As a result, the cholesteric liquid crystal layer can be made into a diffusely reflective layer, and a real image can be displayed. For the diffusely reflective cholesteric liquid crystal layer, reference can be made to Japanese Patent Application Laid-Open No. 2016-004211 and WO2015 / 025909.

[Layer containing multiple cholesteric liquid crystal dots]
Cholesteric liquid crystal dots are formed by dropping a liquid crystal composition that expresses a cholesteric structure directly on a retardation layer or on the surface of an alignment layer or the like by, for example, an inkjet method, and then drying, orientation treatment, and curing as described above. It was made to do. The dots are preferably formed so that the cholesteric liquid crystal dots include a portion where the height of the cholesteric liquid crystal dots continuously increases from the edge to the center of the cholesteric liquid crystal dots to the maximum height of the cholesteric liquid crystal dots, and also on the surface. It is preferable that the spiral axis direction of the cholesteric liquid crystal structure is substantially perpendicular (70 ° to 90 °) to the dot surface (for example, tangent when the surface is a curved surface). For the layer containing a plurality of cholesteric liquid crystal dots, the description of WO2016 / 194327 can be referred to.

As the alignment layer, a layer similar to the alignment layer that can be contained in the peelable support described later can be used.

[Phase difference layer]
The real image display member may include a retardation layer. The retardation layer is arranged so as to be between the support and the layer including the cholesteric liquid crystal structure in the real image display member of the present invention. There is also an embodiment in which a member from which the support is peeled off is used as a member for displaying a real image. By using a retardation layer in which the front retardation is appropriately adjusted in combination with the layer containing the cholesteric liquid crystal structure, higher brightness can be given, and by suppressing reflection of glass or the like, image blurring can be prevented. , Or a clearer projected image can be displayed.

As the retardation layer, a layer obtained by curing a liquid crystal composition containing a polymerizable liquid crystal compound is used. This is because it can be a thinner layer. The retardation layer may be a film in which the polymerizable liquid crystal compound is uniaxially oriented and oriented and fixed. The retardation layer is formed from a layer in which a liquid crystal composition containing a polymerizable liquid crystal compound is applied to the surface of a support or the surface of an alignment film. The polymerizable liquid crystal compound in the applied liquid crystal composition can be formed in a nematic orientation in a liquid crystal state and then fixed by curing to form a retardation layer. In this case, the retardation layer can be formed in the same manner as the cholesteric liquid crystal layer described above, except that a chiral agent is not added to the liquid crystal composition. However, at the time of nematic orientation after application of the liquid crystal composition, the heating temperature is preferably 50 ° C. to 120 ° C., more preferably 60 ° C. to 100 ° C.

The retardation layer is a layer obtained by applying a composition containing a polymer liquid crystal compound to the surface of a support or an alignment film, forming a nematic orientation in a liquid crystal state, and then cooling to fix the orientation. You may.

The thickness of the retardation layer is preferably 0.2 μm to 10 μm, more preferably 0.5 μm to 5.0 μm, and even more preferably 1.0 μm to 2.5 μm.

As the retardation layer, a λ / 4 retardation layer, a λ / 2 retardation layer, or a layer having a phase difference between them can be appropriately used. As the retardation layer, it is preferable to use a λ / 4 retardation layer and a λ / 2 retardation layer.

The front phase difference of the λ / 2 retardation layer may be half the length of the visible light wavelength region or “center wavelength × n ± 1/2 of the center wavelength (n is an integer)”. In particular, the reflection wavelength of the layer containing the cholesteric liquid crystal structure (for example, any cholesteric liquid crystal) or the length of 1/2 of the center wavelength of the emission wavelength of the light source may be used. For example, the phase difference may be in the range of 160 nm to 460 nm, and the phase difference in the range of 200 nm to 410 nm is preferable.

The front phase difference of the λ / 4 retardation layer may be 1/4 of the visible light wavelength region or “center wavelength × n ± 1/4 of the center wavelength (n is an integer)”. In particular, the reflection wavelength of the layer containing the cholesteric liquid crystal structure (for example, any cholesteric liquid crystal) or the length of 1/4 of the center wavelength of the emission wavelength of the light source may be used. For example, the phase difference may be in the range of 100 nm to 230 nm, and the phase difference in the range of 110 nm to 210 nm is preferable.

In the embodiment in which the retardation layer A is a λ / 2 retardation layer, the slow axis direction of the λ / 2 retardation layer is the incident direction of the incident light of the projector and the cholesteric liquid crystal layer when used as a real image display system. It is preferable to determine according to the sense of the spiral of. For example, the incident light is in the direction below (vertically below) the projected image display portion, and is from the λ / 2 retardation layer side with respect to the layer containing the cholesteric liquid crystal structure (in the present specification, "from the observer side"). When incident, the slow axis of the λ / 2 retardation layer may be in the range of + 40 ° to + 65 ° or -40 ° to -65 ° with respect to the vertical upward direction of the projected image display area. preferable. Further, it is preferable that the slow phase axial direction is set as follows according to the sense of the spiral of the cholesteric liquid crystal layer in the layer including the cholesteric liquid crystal structure. When the above sense is on the right (preferably when the sense of all cholesteric liquid crystal layers is on the right), the slow axis of the λ / 2 retardation layer is from the observer side with respect to the vertically upward direction of the projected image display portion. Seen clockwise, it is preferably in the range of 40 ° to 65 °, preferably 45 ° to 60 °. When the above sense is on the left (preferably when the sense of all cholesteric liquid crystal layers is on the left), the slow axis of the λ / 2 retardation layer is viewed from the observer side with respect to the vertically upward direction of the projected image display portion. It is preferably in the range of 40 ° to 65 °, preferably 45 ° to 60 ° counterclockwise.

In the embodiment in which the retardation layer A is a λ / 4 retardation layer, the slow axis direction of the λ / 4 retardation layer is the incident direction of the incident light of the projector and the cholesteric liquid crystal layer when used as a real image display system. It is preferable to determine according to the sense of the spiral of. For example, the incident light is in the direction below (vertically below) the projected image display portion, and is from the λ / 4 retardation layer side with respect to the layer containing the cholesteric liquid crystal structure (in the present specification, "from the observer side"). When incident, the slow axis of the λ / 2 retardation layer may be in the range of + 130 ° to + 160 ° or -130 ° to -160 ° with respect to the vertical upward direction of the projected image display part. preferable. Further, it is preferable that the slow phase axial direction is set as follows according to the sense of the spiral of the cholesteric liquid crystal layer in the layer including the cholesteric liquid crystal structure. When the above sense is on the right (preferably when the sense of all cholesteric liquid crystal layers is on the right), the slow axis of the λ / 4 retardation layer is from the observer side with respect to the vertically upward direction of the projected image display portion. Seen clockwise, it is preferably in the range of 130 ° to 160 °, preferably 130 ° to 150 °. When the above sense is on the left (preferably when the sense of all cholesteric liquid crystal layers is on the left), the slow axis of the λ / 2 retardation layer is viewed from the observer side with respect to the vertically upward direction of the projected image display portion. It is preferably in the range of 130 ° to 160 °, preferably 130 ° to 150 ° counterclockwise.

In the embodiment having the retardation layer B in addition to the retardation layer A, it is preferable that both the retardation A and the retardation B are a λ / 4 retardation layer or a λ / 2 retardation layer. Further, as for the slow axis of the phase difference A and the phase difference B, the slow axis of the above phase difference A is set as described above, and the narrow angle formed by the two phase difference slow axes is 40 °. It is preferable to arrange the slow axis of the phase difference B so as to be ~ 85 °.

In the embodiment in which the real image display member of the present invention is processed into laminated glass, it may be preferable to have retardation layers on both sides of the light reflecting layer. By having the retardation layers on both sides of the light reflection layer, image blurring can be further prevented. In particular, it is possible to further prevent image blurring when a projected image is formed by incident p-polarized light. The effect is more remarkable when a low Δn polymerizable liquid crystal compound is used for forming the cholesteric liquid crystal layer in the layer containing the cholesteric liquid crystal structure.
The reason why image blurring can be further prevented by having retardation layers on both sides of the light reflecting layer is that light having a wavelength not in the selective reflection band of the cholesteric liquid crystal layer contained in the layer including the cholesteric liquid crystal structure is the cholesteric liquid crystal. It is presumed that this is because it is possible to prevent the generation of multiple images caused by polarization conversion in the layer, reflection on the back surface of the laminated glass, and incident on the light reflection layer.
2. When the distance from the layer containing the cholesteric liquid crystal structure to the outermost surface of the glass is 0.5 mm or more, the image blur can be noticeable, when it is 1 mm or more, it can be more noticeable, and when it is 1.5 mm or more, it can be more noticeable. It can be particularly noticeable above 0 mm.

<Support or peelable support>
The real image display member of the present invention may include a support. A peelable support may be used for producing the real image display member of the present invention. The peelable support is peeled off when the glass is bonded or when the interlayer film sheet or laminated glass is manufactured.
Examples of the support or the peelable support include polyesters such as polyethylene terephthalate (PET), polycarbonates, acrylic resins, epoxy resins, polyurethanes, cycloolefin resins, polyamides, polyolefins, cellulose derivatives, and plastic films such as silicones.
As the non-peeling support, a film made of a film containing a cellulose derivative, a cycloolefin resin, and polyethylene terephthalate is preferable.
As the peelable support, a film made of a film containing polyethylene terephthalate is preferable.

The thickness of the non-peeling support is preferably 20 μm or more, and more preferably 40 μm or more. The thickness of the peelable support is preferably 50 μm or more, more preferably 70 μm or more, and further preferably 80 μm or more. This is because a uniform functional layer can be obtained when the peelable support used as the base material for forming the functional layer has a thickness of 50 μm or more. The upper limit of the thickness of the peelable support is not particularly limited, but is preferably 1000 μm or less, more preferably 500 μm or less, and even more preferably 300 μm or less.

The peelable support is preferably a rubbing-treated layer. It suffices that the liquid crystal composition is applied to the rubbing treated surface to form a retardation layer. The rubbing treatment can be carried out by rubbing the surface of the peelable support (the surface of the alignment layer when the alignment layer is provided) with paper or cloth in a certain direction.

The support or detachable support may include an alignment layer. The alignment layer is a lower layer to which the liquid crystal composition is applied when the retardation layer is formed, and in the real image display member of the present invention, a support or a peelable support so as to be in direct contact with the retardation layer. It suffices if it is included in.
The oriented layer has a rubbing treatment of an organic compound such as a polymer (resin such as polyimide, polyvinyl alcohol, polyester, polyarylate, polyamideimide, polyetherimide, polyamide, modified polyamide), oblique deposition of an inorganic compound, and microgrooves. It can be provided by means such as layer formation or accumulation of organic compounds (eg, ω-tricosanoic acid, dioctadecylmethylammonium chloride, methyl stearylate) using the Langmuir-Brojet method (LB membrane). Further, an orientation layer in which an orientation function is generated by applying an electric field, applying a magnetic field, or irradiating light may be used.
The thickness of the alignment layer is preferably 0.01 μm to 5.0 μm, and more preferably 0.05 μm to 2.0 μm.

<Adhesive layer>
The real image display member of the present invention may include an adhesive layer, if necessary.
The adhesive layer may be provided between the cholesteric liquid crystal layers, between the layer containing the cholesteric liquid crystal structure and the retardation layer A, between the layer containing the cholesteric liquid crystal structure and the retardation layer B, and the like.
The adhesive layer is preferably transparent in the visible light region. Further, the adhesive layer preferably has low birefringence, and it is preferable that the difference in refractive index from the average refractive index (in-plane average refractive index) of the cholesteric liquid crystal layer is small.

The adhesive layer may be formed from an adhesive.
From the viewpoint of curing method, there are hot melt type, thermosetting type, photocuring type, reaction curing type, and pressure-sensitive adhesive type that does not require curing, and the materials are acrylate type, urethane type, urethane acrylate type, and epoxy, respectively. Uses compounds such as system, epoxy acrylate system, polyolefin system, modified olefin system, polypropylene system, ethylene vinyl alcohol system, vinyl chloride system, chloroprene rubber system, cyanoacrylate system, polyamide system, polyimide system, polystyrene system, polyvinyl butyral system. can do. From the viewpoint of workability and productivity, the photocuring type, especially the ultraviolet curing type, is preferable as the curing method, and from the viewpoint of optical transparency and heat resistance, acrylate-based, urethane acrylate-based, epoxy acrylate-based, etc. are used as the material. It is preferable to do so.

The thickness of the adhesive layer in the above example is preferably 0.5 μm to 25 μm, more preferably 1.0 μm to 5.0 μm. It is preferable that the projection image display portion is provided with a uniform thickness in order to reduce color unevenness and the like.

The adhesive layer may be formed by using a highly transparent adhesive transfer tape (OCA tape). As the highly transparent adhesive transfer tape, a commercially available product for an image display device, particularly a commercially available product for the surface of an image display portion of an image display device may be used. Examples of commercially available products include adhesive sheets manufactured by Panac Co., Ltd. (PD-S1 and the like), adhesive sheets of the MHM series manufactured by Niei Kako Co., Ltd., and the like.
The thickness of the OCA tape may be 1.0 μm to 50 μm, preferably 2.0 μm to 30 μm.
<Laminated glass>
The real image display member of the present invention can be used for manufacturing laminated glass. Further, the real image display member of the present invention can be used for manufacturing an intermediate layer of laminated glass. The member for displaying a real image of the present invention can be used as a material for providing a function as a half mirror film in an intermediate layer of glass. Further, the real image display member of the present invention is a manufacturing intermediate in the manufacture of laminated glass having a retardation layer in the intermediate layer.

The laminated glass has a structure in which two glass plates are adhered to each other via an intermediate layer. The laminated glass produced by using the real image display member of the present invention includes a first glass plate, a first resin film, a real image display member, a second resin film, and a second glass plate in this order. .. An example of laminated glass is schematically shown with reference to FIG. The first glass plate 31, the first resin film 11, the real image display member 13 including the cholesteric liquid crystal structure, the second resin film 12, and the second glass plate 32 are arranged in this order. The intermediate layer 21 is composed of a first resin film 11, a real image display member 13 including a cholesteric liquid crystal structure, and a second resin film 12.

Laminated glass is typically used as windshield glass. In the present specification, the windshield glass means a window glass of a vehicle such as a car or a train, or a general vehicle such as an airplane, a ship, or a plaything. The windshield glass is preferably a windshield in the direction of travel of the vehicle. The windshield glass is preferably the windshield of the vehicle.

The laminated glass may be flat. The laminated glass may be molded for incorporation into the vehicle to which it is applied and may have, for example, a curved surface. In the laminated glass formed for the applied vehicle, the direction to be upward (vertically upward) and the surface to be the observer side can be specified during normal use. In the present specification, when the laminated glass or the projected image display portion is vertically above, it means the direction in which the laminated glass or the projected image display portion is vertically above when used, which can be specified as described above.

<Glass plate>
In the present specification, in the laminated glass, the outer glass plate is referred to as the first glass plate, and the glass plate on the indoor side is referred to as the second glass plate. In other words, the glass plate located farther from the driver (observer side) is called the first glass plate, and the glass plate located closer to the driver (observer side) is called the second glass plate.
In the present specification, the term "glass plate" means both a first glass plate and a second glass plate.

As the glass plate, a glass plate generally used for laminated glass for windshield glass can be used. The thickness of the glass plate is not particularly limited, but may be about 0.5 mm to 5.0 mm, preferably 1.0 mm to 3.0 mm, and more preferably 1.6 mm to 2.3 mm. The thickness of the first glass plate and the second glass plate may be the same or different from each other. For example, the first glass plate may be 1.9 mm to 2.5 mm, and the second glass plate may be 1.6 mm to 1.9 mm.

The surface of the glass plate may be surface-treated to impart water repellency, hydrophilicity, antifogging property, or the like.
The glass plate is preferably cut into the shape of windshield glass. Further, it is preferable to have a curved surface. The curved surface can be provided by placing the cut glass plate on a jig having the same curvature as the windshield glass to be manufactured and heating (for example, 600 to 700 ° C.).

<Resin film>
In the present specification, when the laminated glass is used as the windshield glass, the outer resin film is referred to as the first resin film, and the resin film on the indoor side is referred to as the second resin film. In other words, the resin film located farther from the driver (observer) side is referred to as the first resin film, and the resin film located closer to the driver (observer) side is referred to as the second resin film.
The first resin film and the second resin film may be the same or different in terms of material, thickness, and the like. The materials are preferably the same, more preferably the materials and thicknesses are the same.

In the present specification, the term "resin film" means both the first resin film and the second resin film.
The resin film may have the same shape and area as the first glass plate. For example, in the manufacturing process of laminated glass, even if the resin film unwound from the roll form is sandwiched between the first glass plate and the second glass plate and then trimmed to form the shape of the first glass plate. Good.

As the resin film, a resin film known as a sheet used for the intermediate layer of the laminated glass may be used. The resin film contains resin as a main component. The main component means a component that occupies a ratio of 50% by mass or more of the interlayer film sheet.
The resin is preferably a synthetic resin. For example, the resin may be a thermoplastic resin. Examples of the thermoplastic resin include thermoplastic resins conventionally used for intermediate layers of laminated glass, such as polyvinyl acetal, polyvinyl chloride, saturated polyester, polyurethane, ethylene-vinyl acetate copolymer, and ethylene. -Ethylene acrylate copolymer and the like can be mentioned. Of these, polyvinyl acetal is preferable from the viewpoint of transparency, strength, light resistance and the like.

Polyvinyl acetal is a general term for resins in which polyvinyl alcohol is acetalized with an aldehyde in the presence of an acid. For example, polyvinyl formal converted with formalin (37% formaldehyde aqueous solution) as an aldehyde, and butanol (butyl alcohol) as an aldehyde. Examples thereof include acetalized polyvinyl butyral (hereinafter, may be referred to as “PVB”).

Among the above resins, polyvinyl butyral or ethylene-vinyl acetate copolymer is preferable, and polyvinyl butyral is more preferable. As described above, polyvinyl butyral can be obtained by acetalizing polyvinyl alcohol with butyraldehyde. The preferred lower limit of the degree of acetalization of polyvinyl butyral is 40%, the preferred upper limit is 85%, the more preferred lower limit is 60%, and the more preferred upper limit is 75%.

Polyvinyl alcohol is usually obtained by saponifying polyvinyl acetate, and polyvinyl alcohol having a saponification degree of 80 to 99.8 mol% is generally used.
The preferable lower limit of the degree of polymerization of the polyvinyl alcohol is 200, and the preferable upper limit is 3000. When the degree of polymerization of polyvinyl alcohol is 200 or more, the penetration resistance of the obtained laminated glass is unlikely to decrease, and when it is 3000 or less, the moldability of the resin film is good and the rigidity of the resin film does not become too large. Good workability. A more preferred lower limit is 500 and a more preferred upper limit is 2000.

It is also preferable that the resin is plasticized by adding a plasticizer. For example, as the plasticizer, a phosphoric acid ester, a carboxylic acid ester, a sugar ester, a polycondensation ester or the like is used.
The amount of the plasticizer added is preferably 10 parts by mass or more and 80 parts by mass or less with respect to 100 parts by mass of the resin. By adding 10 parts by mass or more of the plasticizer, the thermoplastic resin can be sufficiently plasticized. Further, by setting the amount of the plasticizer added to 80 parts by mass or less, the strength of the resin layer can be sufficiently maintained.

In addition to the above plasticizers, the resin film or the composition for forming the resin film includes infrared shielding fine particles, an adhesive modifier, a coupling agent, a surfactant, an antioxidant, a heat stabilizer, a light stabilizer, and the like. It may contain one or more of various additives such as an ultraviolet absorber, a fluorescent agent, a dehydrating agent, a defoaming agent, an antistatic agent, and a flame retardant.

The thickness of the resin film is preferably, for example, 0.1 mm to 1.5 mm, more preferably 0.2 mm to 1.0 mm.

<Manufacturing method of real image display member>
The real image display member can be manufactured by providing a light reflecting layer including a cholesteric liquid crystal layer on the surface of a laminate obtained by forming a retardation layer and an alignment layer on a support or a peelable support. ..
As a manufacturing method, a method of crimping both at a constant temperature, a constant pressure, and a constant time, and a method of crimping by roll-to-roll (laminating at a constant pressure as a roll above a predetermined temperature and a roll below a predetermined temperature). However, any method may be used.
The heating and pressurization during the above crimping are, for example, a temperature of 40 ° C. or higher and 140 ° C. or lower, preferably a temperature of 60 ° C. or higher and 120 ° C. or lower, a pressure of 0.05 MPa or higher and 0.8 MPa or lower, preferably 0.1 MPa or higher and 0.5 MPa or lower. You can do it below.

<Manufacturing method of interlayer film sheet and laminated glass>
The interlayer film sheet can be manufactured by a manufacturing method including providing a first resin film on the real image display member of the present invention. The second resin film can be provided by any of the procedures listed as the procedure for providing the first resin film on the surface of the functional layer.

The laminated glass can be produced by using a known laminated glass manufacturing method. For example, it can be produced by performing preliminary crimping and main crimping on a laminate obtained by sandwiching the interlayer film sheet obtained as described above between two glass plates. Alternatively, a second resin film and a second glass plate are provided on one side of the real image display member in this order, and a first resin film and a first glass plate are provided on the opposite surface of the real image display member. It can be manufactured by a manufacturing method including provision. When the second resin film and the second glass plate, and the first glass plate are provided, the second glass plate, the second resin film, the actual image display member, the first resin film, and the first It can be manufactured by laminating glass plates in this order and performing preliminary crimping and main crimping on the laminated body. Further, each of them may be sequentially crimped, or a first glass plate on which the first resin film is provided in advance may be used.

Pre-crimping is a process performed for degassing between layers in the manufacture of laminated glass. Pre-crimping is performed, for example, by placing the laminate in a rubber bag connected to the exhaust system. The pressure at this time is preferably 100 kPa or less, and more preferably 1 to 36 kPa. Pre-crimping can be performed by holding the temperature at 70 ° C. to 130 ° C. for 10 minutes or more and 90 minutes or less.

Preliminary crimping can be sufficiently performed by setting the holding temperature to 70 ° C. or higher. Further, by setting the holding temperature to 130 ° C. or lower, it is possible to suppress the excessive progress of heat shrinkage of the functional layer, so that the occurrence of cracks in the functional layer can be suppressed. The holding temperature is preferably 80 ° C. or higher, more preferably 90 ° C. or higher. This is to perform degassing more reliably. The holding temperature is preferably 120 ° C. or lower, more preferably 110 ° C. or lower.

When the holding time is 10 minutes or more, preliminary crimping can be sufficiently performed. On the other hand, when the holding time is 90 minutes or less, the productivity is good and the heat shrinkage of the functional layer material can be suppressed from excessively progressing, so that the occurrence of cracks in the functional layer can be suppressed. The holding time is preferably 20 minutes or more and 60 minutes or less from the viewpoint of performing preliminary crimping more effectively and efficiently.

This crimping is performed in order to sufficiently bond each layer with a resin film. For example, a pre-crimping body obtained by pre-crimping is placed in an autoclave, the temperature is 120 ° C. or higher and 150 ° C. or lower, and the pressure is 0.98 MPa. This can be done at 1.47 MPa or less. More preferably, the temperature is 130 ° C. or higher and 140 ° C. or lower, and the pressure is 1.1 MPa or higher and 1.4 MPa or lower. The time (holding time) for holding the temperature and pressure is preferably 30 minutes or more and 90 minutes or less, and more preferably 45 minutes or more and 75 minutes or less.

By performing the main crimping with the holding temperature, holding pressure, or holding time as the above conditions, it is possible to suppress the occurrence of cracks in the functional layer, and the productivity and the like are also excellent.

<< Real image display system >>
The real image display system includes the real image display member of the present invention and the projector. The real image display system may be a head-up display system. Laminated glass can be used as a component of a head-up display system.

<Projector>
In the present specification, the "projector" is a "device that projects light or an image" and includes a "device that projects a drawn image". In the real image display system, the projector may be arranged so that it can be incident on, for example, a real image display member attached to a glass plate or a real image display member in a laminated glass at an oblique incident angle as described above.
In a real image display system, it is preferable that the projector includes a drawing device and displays a real image on the real image display member by focusing on the real image display member.

[Drawing device]
The drawing device itself may be a device that displays an image, or may be a device that emits light capable of drawing an image. In the drawing device, the light from the light source may be adjusted by a drawing method such as an optical modulator, a laser luminance modulation means, or a light deflection means for drawing. In the present specification, a drawing device includes a light source, and further means a device including a light modulator, a laser luminance modulation means, a light deflection means for drawing, and the like depending on a drawing method.

(light source)
The light source is not particularly limited, and an LED (including a light emitting diode and an organic light emitting diode (OLED)), a discharge tube, a laser light source, and the like can be used. Of these, LEDs and laser light sources are preferred. This is because it is suitable as a light source for a drawing device that emits linearly polarized light.

(Drawing method)
The drawing method can be selected according to the light source to be used and the intended use, and is not particularly limited.
Examples of drawing methods include a fluorescent display tube, an LCD (Liquid Crystal Display) method using a liquid crystal display, an LCOS (Liquid Crystal on Silicon) method, a DLP (registered trademark) (Digital Light Processing) method, and a scanning method using a laser. And so on. The drawing method may be a method using a fluorescent display tube integrated with a light source.

In the LCD system and the LCOS system, the light of each color is modulated and combined by an optical modulator, and the light is emitted from the projection lens.
The DLP method is a display system using a DMD (Digital Micromirror Device), and is drawn by arranging micromirrors for the number of pixels and emitting light from a projection lens.
The scanning method is a method in which light rays are scanned on a screen and contrast is performed using the afterimage of the eyes. For example, the descriptions in JP-A-7-270711 and JP-A-2013-228674 can be referred to. In the scanning method using a laser, the laser light of each brightness-modulated color (for example, red light, green light, blue light) is bundled into one light beam by a combined wave optical system or a condenser lens, and the light beam is light. It suffices that it is scanned by the deflection means and drawn on the intermediate image screen described later.

In the scanning method, the brightness modulation of the laser light of each color (for example, red light, green light, blue light) may be performed directly as a change in the intensity of the light source, or may be performed by an external modulator. Examples of the light deflection means include a galvano mirror, a combination of a galvano mirror and a polygon mirror, and a MEMS (microelectromechanical system), of which MEMS is preferable. Examples of the scanning method include a random scan method and a raster scan method, but it is preferable to use the raster scan method. In the raster scan method, the laser beam can be driven by, for example, a resonance frequency in the horizontal direction and a sawtooth wave in the vertical direction. Since the scanning method does not require a projection lens, the device can be easily miniaturized.

The light emitted from the drawing device may be linearly polarized light or natural light (non-polarized light). The light emitted from the drawing device included in the real image display system is preferably linearly polarized light. In a drawing device whose drawing method is LCD or LCOS and a drawing device using a laser light source, the emitted light is essentially linearly polarized light. In a drawing device in which the emitted light is linearly polarized light and the emitted light contains light of a plurality of wavelengths (colors), the polarization directions (transmission axis directions) of the polarizations of the plurality of lights are the same or orthogonal to each other. It is preferable to do so. It is known that some commercially available drawing devices do not have uniform polarization directions in the wavelength ranges of red, green, and blue light emitted (see Japanese Patent Application Laid-Open No. 2000-22149). Specifically, there are known examples in which the polarization direction of green light is orthogonal to the polarization direction of red light and the polarization direction of blue light.

[Projected light (incident light)]
It is preferable that the incident light is incident at an oblique incident angle of 45 ° to 70 ° with respect to the normal of the projected image display portion. When the projected light is reflected on the front surface or the back surface of the glass, it is diffusely reflected by the real image display member again, resulting in image blurring due to multiple images. This is because it is useful to make the projected light (p-polarized light) incident on the glass surface at the Brewster's angle so that the reflected light from the glass surface approaches zero as a method for reducing the image blur. (See, for example, Japanese Patent Application Laid-Open No. 2006-512622). Further, in the embodiment in which the real image display member having the retardation layer A is bonded to the glass, the Brewster angle at the interface between the glass having a refractive index of about 1.51 and the air having a refractive index of 1 is about 56 °. When p-polarized light is incident from the glass side in the above angle range, the circularly polarized light selectively reflected by the layer containing the cholesteric liquid crystal structure is converted to p-polarized light by the retardation layer A, so that the reflected light from the glass It is possible to display an image with less blurring. The angle is also preferably 50 ° to 65 °.

In the embodiment in which the real image display member of the present invention has the retardation layer A, the incident light is incident on the layer including the cholesteric liquid crystal structure from the retardation layer A side, and the incident light is incident on the cholesteric liquid crystal structure via the retardation layer A. It may be incident on the layer containing. That is, the retardation layer A may be arranged on the incident side of the projected light with respect to the layer including the cholesteric liquid crystal structure. Further, the incident light may be incident from any direction such as up, down, left and right of the laminated glass, and may be determined in correspondence with the direction of the observer. For example, it may be incident at an oblique incident angle as described above from the lower direction during use.

As described above, it is preferable that the projected light at the time of displaying the projected image in the real image display system is p-polarized light that vibrates in the direction parallel to the incident surface. When the emitted light of the projector is not linearly polarized light, it may be p-polarized by arranging a linearly polarizing film on the emitted light side of the projector, or even if it is p-polarized in the optical path from the projector to the laminated glass. Good. As described above, for projectors in which the polarization directions of the emitted light in the red, green, and blue wavelength ranges are not uniform, the polarization directions are selectively adjusted in the wavelength range to obtain p-polarization in all color wavelength ranges. It is preferable to make it incident.

The real image display member of the present invention is particularly useful for a transparent screen or a head-up display system in which a laser, an LED, an OLED, or the like whose emission wavelength is not continuous in the visible light region is used in combination with a projector as a light source. This is because the center wavelength of the selective reflection of the cholesteric liquid crystal layer can be adjusted according to each emission wavelength.

Hereinafter, the present invention will be specifically described based on Examples. The materials, reagents, amounts of substances and their ratios, operations, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the present invention is not limited to the following examples.

[Comparative Example 1]
<Manufacturing of display member RS-1>
A commercially available λ / 4 film "Pure Ace WR-S" (manufactured by Teijin Limited) was prepared and used as the retardation layer RE-1. PRL-1, PRL-2, PRL-3, and PRL-4, which are light-reflecting layers composed of a cholesteric liquid crystal layer, are produced in the same manner as in Example 2 described in Japanese Patent No. 5973109, and the acrylic pressure-sensitive adhesive SK is produced. It was laminated on the retardation layer RE-1 using −2057 (manufactured by Soken Kagaku Co., Ltd.). Furthermore, another RE-1 is prepared and laminated on PRL-4 located at the top of the laminated surface using an acrylic adhesive SK-2057 (manufactured by Soken Chemical Co., Ltd.) for display. Member RS-1 was produced.

[Example 1]
<Manufacturing of display member RS-2>

<Preparation of alignment layer Y1>
As a peelable support, on the surface of Cosmo Shine A-4100 (PET, thickness 75 μm) manufactured by Toyobo Co., Ltd., which has not been easily adhered, the alignment layer coating liquid Y1 having the following composition is applied with a wire bar coater of # 3.6. It was applied. Then, it was dried at 45 ° C. for 60 seconds ^{and irradiated with ultraviolet rays of 500 mJ / cm 2} at 25 ° C. by an ultraviolet irradiation device to prepare an alignment layer Y1 with a peeling support.

(Orientation layer coating liquid Y1)
・ KAYARAD PET30 (manufactured by Nippon Kayaku Co., Ltd.) 100 parts by mass ・ IRGACURE 907 (manufactured by BASF Co., Ltd.) 3.0 parts by mass ・ Kayacure DETX (manufactured by Nippon Kayaku Co., Ltd.) 1.0 parts by mass ・ Fluorine System horizontal alignment agent F1 0.01 part by mass, methyl isobutyl ketone 243 parts by mass

Fluorine-based horizontal alignment agent F1

<Preparation of cholesteric liquid crystal layers B1, G1, R1, IR1, IR2>
(Cholesteric liquid crystal layer coating liquid B1, G1, R1, IR1, IR2)
The following components were mixed to prepare a coating liquid for forming a cholesteric liquid crystal layer having the following composition.
・ Mixture of compound 1 100 parts by mass ・ Fluorine-based horizontal alignment agent F1 0.08 parts by mass ・ Fluorine-based horizontal alignment agent F2 0.20 parts by mass ・ Right-turning chiral agent LC-756 (manufactured by BASF)
Listed in Table 1 ・ IRGACURE OXE01 (manufactured by BASF) 1.5 parts by mass ・ Methyl ethyl ketone Listed in Table 2.

Mixture of compound 1 (numerical value is% by mass)

Fluorine-based horizontal alignment agent F2

The prescription amount of the chiral agent LC-756 and the amount of methyl ethyl ketone in the above coating liquid composition were adjusted to prepare cholesteric liquid crystal coating liquids B1, G1, R1, IR1 and IR2. Using each coating solution, a single-layer cholesteric liquid crystal layer was prepared on the peelable support in the same manner as when the following functional layers were produced, and the reflection characteristics were confirmed. As a result, all the produced cholesteric liquid crystal layers were in the right circle. It is a polarized light reflecting layer, and the central reflection wavelength is as shown in Table 1 below.
Here, the central reflectance wavelength is a cholesteric liquid crystal using a spectrophotometer (manufactured by Nippon Spectral Co., Ltd., V-550) equipped with a large integrating sphere device (manufactured by Nippon Spectral Co., Ltd., ILV-471). It is a value calculated based on the integrated reflectance measured without using an optical trap so that light is incident from the layer side. Specifically, it is a mountain shape with the wavelength as the horizontal axis (convex upward). The average reflectance (arithmetic average) of the maximum value and the minimum value of the integrated reflectance in the integrated reflectance spectrum is obtained, and the value of the wavelength on the short wave side of the two wavelengths of the two intersections of the waveform and the average reflectance is λA ( nm), the value of the wavelength on the long wave side is λB (nm), and it is a value calculated by the following formula.
Central reflection wavelength = (λA + λB) / 2

The coating liquid B1 for the cholesteric liquid crystal layer prepared above was applied to the surface of the alignment layer Y1 with a peeling support with a wire bar coater of # 2.6. Then, it was dried at 95 ° C. for 60 seconds ^{and irradiated with ultraviolet rays of 500 mJ / cm 2} at 25 ° C. to prepare a cholesteric liquid crystal layer B1 that reflects light having a center wavelength of 435 nm. Next, the coating liquid G1 for the cholesteric liquid crystal layer prepared above was applied to the surface of the cholesteric liquid crystal layer B1 layer with a # 2.0 wire bar coater. Then, it was dried at 95 ° C. for 60 seconds, and by irradiating ultraviolet rays of 500 mJ / cm ² at 25 ° C. with an ultraviolet irradiation device, a cholesteric liquid crystal layer G1 that reflects light having a center wavelength of 545 nm was laminated. Next, the coating liquid R1 for the cholesteric liquid crystal layer prepared above was applied to the surface of the cholesteric liquid crystal layer G1 with a # 2.0 wire bar coater. Then, it was dried at 95 ° C. for 60 seconds, and by irradiating ultraviolet rays of 500 mJ / cm ² at 25 ° C. with an ultraviolet irradiation device, a cholesteric liquid crystal layer R1 that reflects light having a center wavelength of 650 nm was laminated. Next, the coating liquid IR1 for the cholesteric liquid crystal layer prepared above was applied to the surface of the prepared cholesteric liquid crystal layer R1 with a wire bar coater of # 2.6. Then, it was dried at 95 ° C. for 60 seconds, and by irradiating ultraviolet rays of 500 mJ / cm ² at 25 ° C. with an ultraviolet irradiation device, a cholesteric liquid crystal layer IR1 that reflects light having a center wavelength of 840 nm was laminated. Further, the display member RS-2 was produced by peeling off the peeling support.

[Example 2]
<Manufacturing of display member RS-3>

<Manufacturing of retardation layers RE-2 to RE-7>
(Coating liquid RE-2 for forming a retardation layer)
The following components were mixed to prepare a coating liquid RE-2 for forming a retardation layer having the following composition.
・ Mixture of compound 1 100 parts by mass ・ Fluorine-based horizontal alignment agent F1 0.01 parts by mass ・ Fluorine-based horizontal alignment agent F2 0.05 parts by mass ・ IRGACURE OXE01 (manufactured by BASF)
1.0 part by mass ・ Amount at which the solute concentration of methyl ethyl ketone is 25% by mass

As a peelable support, the surface of Cosmo Shine A-4100 (PET, thickness 75 μm) manufactured by Toyobo Co., Ltd., which has not been easily adhered, is subjected to rubbing treatment in the direction rotated 60 ° counterclockwise from the TD direction. The coating liquid RE-2 for forming a difference layer was applied using a wire bar. Then, it is dried at 50 ° C. for 60 seconds ^{, irradiated with ultraviolet rays of 500 mJ / cm 2} at 50 ° C. to fix the liquid crystal phase, and has a retardation layer having a thickness of 1.34 μm. The attached retardation layer RE-2 was produced. At this time, when the front retardation Re (550) of the retardation layer at a wavelength of 550 nm was measured by AxoScan (manufactured by Axometrics), Re (550) was 260 nm.

In the production of the retardation layer RE-2 with a peeling support, the same method was used except that the bar count was changed to adjust the film thickness and the rubbing angle was adjusted so as to have the configuration shown in Table 3. , Phase difference layers RE-3 to 7 with a peeling support were prepared. Table 2 below shows the results of measuring the front retardation Re (550) of the retardation layer at a wavelength of 550 nm with AxoScan (manufactured by Axometrics).

In the production of the display member RS-2, the alignment layer is placed on the retardation layer in the same manner except that the retardation layer RE-2 with the peeling support is used instead of the peelable support A-4100. And the cholesteric liquid crystal layers B1, G1, R1 and IR1 were formed in this order. Next, the retardation layer RE-5 with a peeling support was bonded to the surface of the produced cholesteric liquid crystal layer IR1 using an acrylic pressure-sensitive adhesive SK-2057 (manufactured by Soken Chemical Co., Ltd.), and then both sides of the laminated body were laminated. The display member RS-3 was manufactured by peeling both of the peeling supports in the above.

[Examples 3 to 13]
<Manufacturing of display members RS-4 to 14>
In the production of the display member RS-3, the display member RS-4 to RS-4 to the display member RS-4 to the same method except that the retardation layer with the peeling support, the alignment film, and the cholesteric liquid crystal layer were changed so as to be the combination shown in Table 3 below. 14 was made. Among the display members RS-4 to 14, in the embodiment in which the retardation layers RE-2 to 7 with a peelable support are used, the one in which the peelable support is finally peeled off is used as the display member. In the embodiment using the retardation layers RE-8 and RE-9, the retardation layer was formed on the alignment film Y2 to produce a display member.

<Preparation of cholesteric liquid crystal layers G2 and G4-7>
In the production of the cholesteric liquid crystal layer G1, the cholesteric liquid crystal layer G2 was produced by the same method except that the bar count was changed to # 2.8. In the same manner, the cholesteric liquid crystal layers G4 to 7 were produced in the same manner except that the bar count was changed.

<Preparation of cholesteric liquid crystal layers G3 and IR3>
In the coating liquid G1 and the coating liquid IR2, 0.1 part by mass of MEK-AC-4130 (spherical silica particles having an average primary particle size of 45 nm manufactured by Nissan Chemical Industries, Ltd.) is added to 100 parts by mass of the mixture of compound 1. Then, the coating liquid G3 and IR3 were adjusted.
In the preparation of the cholesteric liquid crystal layer G2, the cholesteric liquid crystal layer G3 was prepared in the same manner except that the coating liquid was changed to G3.
In the preparation of the cholesteric liquid crystal layer IR2, the cholesteric liquid crystal layer IR3 was prepared in the same manner except that the coating liquid was changed to IR3.

<Preparation of cholesteric liquid crystal layer IR4-7>
In the preparation of the cholesteric liquid crystal layer IR2, the cholesteric liquid crystal layers IR4 to 7 were prepared in the same manner except that the bar count was changed.

[Example 14]
<Preparation of cholesteric liquid crystal layers B2, G8, R2>
(Cholesteric liquid crystal layer coating liquids B2, G8, R2)
The following components were mixed to prepare a coating liquid for forming a cholesteric liquid crystal layer having the following composition.
-Mixture of compound 1 100 parts by mass-Fluorine-based orientation agent F3 Listed in Table 3-Right-turning chiral agent LC-756 (manufactured by BASF)
Table 3 ・ IRGACURE OXE01 (manufactured by BASF) 1.5 parts by mass ・ Methyl ethyl ketone Listed in Table 3 ・ Cyclohexanone Described in Table 3.

Fluorine-based horizontal alignment agent F3

Cholesteric liquid crystal coating liquids B2, G8, and R2 were prepared by adjusting the prescribed amounts of the fluorine-based horizontal alignment agent F3 and the chiral agent LC-756, the amount of methyl ethyl ketone, and the amount of cyclohexanone in the coating liquid composition. Using each coating solution, a single-layer cholesteric liquid crystal layer was prepared on the peelable support in the same manner as when the following functional layers were produced, and the reflection characteristics were confirmed. As a result, all the produced cholesteric liquid crystal layers were in the right circle. It is a polarized light reflecting layer, and the central reflection wavelength is as shown in Table 3 below.

The coating liquid B1 for the cholesteric liquid crystal layer prepared above was applied to the surface of the alignment layer Y1 with a peeling support with a wire bar coater of # 3. Then, it was dried at 45 ° C. for 60 seconds ^{and irradiated with ultraviolet rays of 500 mJ / cm 2} at 40 ° C. to prepare a cholesteric liquid crystal layer B2 that reflects light having a center wavelength of 482 nm. Next, the coating liquid G8 for the cholesteric liquid crystal layer prepared above was applied to the surface of the cholesteric liquid crystal layer B2 layer with a # 3 wire bar coater. Then, it was dried at 45 ° C. for 60 seconds, and by irradiating ultraviolet rays of 500 mJ / cm ² at 40 ° C. with an ultraviolet irradiation device, a cholesteric liquid crystal layer G1 that reflects light having a center wavelength of 606 nm was laminated. Next, the coating liquid R1 for the cholesteric liquid crystal layer prepared above was applied to the surface of the cholesteric liquid crystal layer G8 with a wire bar coater of # 3. Then, it was dried at 45 ° C. for 60 seconds, and by irradiating ultraviolet rays of 500 mJ / cm ² at 40 ° C. with an ultraviolet irradiation device, a cholesteric liquid crystal layer R1 that reflects light having a center wavelength of 667 nm was laminated. Further, the display member RS-14 was produced by peeling off the peeling support.

<Manufacturing of retardation layers RE-8 to RE-9>
<Preparation of transparent support A>
(Preparation of cellulose ester solution for air layer)
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose ester solution for an air layer.

Composition of Cellulose Ester Solution for Air Layer-Cellulose Ester (Acetyl Substitution 2.86) 100 parts by mass-Sugar ester compound of formula (RI) 3 parts by mass-Sugar ester compound of formula (R-II) 1 part by mass -The following ultraviolet absorber 2.4 parts by mass-Silica particle dispersion (average particle size 16 nm) "AEROSIL R972",
Made by Nippon Aerodil Co., Ltd. 0.026 parts by mass, 339 parts by mass of methylene chloride, 74 parts by mass of methanol, 3 parts by mass of butanol

(Preparation of cellulose ester solution for drum layer)
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose ester solution for a drum layer.

Composition of Cellulose Ester Solution for Drum Layer-Cellulose Ester (Acetyl Substitution 2.86) 100 parts by mass-Sugar ester compound of formula (RI) 3 parts by mass-Sugar ester compound of formula (R-II) 1 part by mass -Ultraviolet absorber 2.4 parts by mass-Silica particle dispersion (average particle size 16 nm) "AEROSIL R972",
Made by Nippon Aerodil Co., Ltd. 0.091 parts by mass, methylene chloride 339 parts by mass, methanol 74 parts by mass, butanol 3 parts by mass

(Preparation of cellulose ester solution for core layer)
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose ester solution for a core layer.

Composition of cellulose ester solution for core layer-Cellulose ester (acetyl substitution degree 2.86) 100 parts by mass-Sugar ester compound of formula (R-II) 8.3 parts by mass-Sugar ester compound of formula (R-II) 2 .8 parts by mass, 2.4 parts by mass of the above ultraviolet absorber, 266 parts by mass of methylene chloride, 58 parts by mass of methanol, 2.6 parts by mass of butanol

(Membrane formation by co-current spreading)
As the casting die, a device equipped with a feed block adjusted for co-casting was used so that a film having a three-layer structure could be formed. The cellulose ester solution for the air layer, the cellulose ester solution for the core layer, and the cellulose ester solution for the drum layer were co-cast on a drum cooled to −7 ° C. from the outlet. At this time, the flow rate of each doping was adjusted so that the thickness ratio was air layer / core layer / drum layer = 7/90/3.
It was cast on a mirror-finished stainless steel support, which is a drum with a diameter of 3 m. A dry air of 34 ° C. ^{was applied on the drum at 270 m 3} / min.
Then, 50 cm before the end point of the casting portion, the cellulose ester film that had been cast and rotated was peeled off from the drum, and then both ends were clipped with a pin tenter. At the time of peeling, 5% stretching was performed in the transport direction (longitudinal direction).

The cellulose ester web held by the pin tenter was transported to the drying zone. For the first drying, a dry air of 45 ° C. was blown, and then the drying was performed at 110 ° C. for 5 minutes. At this time, the cellulose ester web was conveyed while being stretched at a magnification of 10% in the width direction.
After the web was separated from the pin tenter, the portion held by the pin tenter was continuously cut off, and unevenness with a width of 15 mm and a height of 10 μm was formed on both ends of the web in the width direction. The width of the web at this time was 1610 mm. It was dried at 140 ° C. for 10 minutes while applying a tensile stress of 210 N in the transport direction. Further, the end portion in the width direction was continuously cut so that the web had a desired width, and a cellulose ester film having a film thickness of 41 μm was prepared. This film is designated as the transparent support A.

<Preparation of alignment film Y2>
The alignment layer coating liquid Y2 having the following composition was applied to the surface of the transparent support A with a # 16 wire bar coater. Then, it was dried at 60 ° C. for 60 seconds and further at 90 ° C. for 150 seconds. Next, the coated surface side was rotated with a rubbing roll in a direction parallel to the transport direction at a clearance of 1.0 mm and 1000 rotations / minute to perform a rubbing treatment, thereby producing a transparent support with an alignment layer Y2. The alignment film Y2 and the transparent support were in close contact with each other and could not be peeled off.

(Orientation layer coating liquid Y2)
・ 10 parts by mass of the following modified polyvinyl alcohol ・ 370 parts by mass of water ・ 120 parts by mass of methanol ・ 0.5 parts by mass of glutaraldehyde (crosslinking agent)

In the production of the retardation layer RE-3 with the peeling support, the retardation layer is placed on the alignment layer Y2 in the same manner except that the transparent support with the alignment layer Y2 is used instead of the peeling support A-4100. The retardation layer RE-8 in which the above was formed was produced. When the front retardation Re (550) of the retardation layer at a wavelength of 550 nm was measured by AxoScan (manufactured by Axometrics), Re (550) was 140 nm.

In the production of the retardation layer RE-8, the retardation layer RE having the retardation layer having a film thickness of 1.90 μm is adjusted by the same method except that the bar count is changed to adjust the film thickness and the rubbing angle is adjusted. -9 was prepared. When the front retardation Re (550) of the retardation layer at a wavelength of 550 nm was measured by AxoScan (manufactured by Axometrics) with AxoScan (manufactured by Axometrics), Re (550) was 370 nm.

<Manufacturing of retardation layer RE-10>
A retardation layer RE-10 was prepared by subjecting a commercially available norbornene-based polymer film "ZEONOR ZF14" (manufactured by Optes Co., Ltd.) to uniaxial stretching at a free end at a temperature of 156 ° C. at a stretching ratio of 45%. When the front retardation Re (550) of the retardation layer at a wavelength of 550 nm was measured by AxoScan (manufactured by Axometrics) with AxoScan (manufactured by Axometrics), Re (550) was 140 nm and Rth (550) was 70 nm. there were.

<Evaluation>
Table 4 below shows the results of measurement and evaluation using the display members produced in Examples and Comparative Examples.

<Measurement of integrated reflectance>
A large integrating sphere device (manufactured by JASCO Corporation, ILV-471) is attached to a spectrophotometer (manufactured by JASCO Corporation, V-550) so that light is incident from the phase difference A side shown in Table 4. The integrated reflection spectrum of the display member was measured so as to include the positively reflected light without using an optical trap. In the obtained integrated reflection spectrum, the maximum reflectance at a wavelength of 620 to 680 nm was defined as the integrated reflectance. It is known that the selective reflection center wavelength of the cholesteric liquid crystal layer shifts to a short wave by increasing the detection angle. The reflection band measured at a wavelength of 620 to 680 nm in vertical incident corresponds to a reflection band having a wavelength of around 550 nm when incident from a polar angle of 60 °.

<Measurement of reflectance>
The incident angle (extreme angle, azimuth angle), light receiving angle (extreme angle, azimuth angle), and measurement wavelength range are appropriately set so that light is incident from the phase difference A side shown in Table 4, and the three-dimensional variable angle is changed. Reflectances R [-60,40] (550) and R [-60,30] (550) of display members using a spectroscopic color measurement system (GCMS-3B, manufactured by Murakami Color Technology Laboratory Co., Ltd.). Was measured. Here, R [-60, θ] (550) is the polar angle θ at an azimuth angle 180 ° deviated from the azimuth angle of the incident light with respect to the incident light having a polar angle of −60 ° on the decorative sheet. It is the reflectance at a wavelength of 550 nm measured by the light receiving angle. Further, when the specular reflectivity is high and the reflected light of R [-60,30] (550) is 0%, it is described as “cannot be calculated” in Table 4.

<Measurement of the average value of the inter-peak distance of the wavy structure>
When the cross section of the cholesteric liquid crystal layer of the display member is observed using a scanning electron microscope (SEM), a striped pattern of bright and dark areas is observed. From the wavy structure of the striped pattern, the distance in the plane direction of the cholesteric liquid crystal layer was measured for the two closest peaks or valleys with an inclination angle of 0 °. The arithmetic mean value of the cholesteric liquid crystal layer having a length of 100 μm in the long axis direction of the cross section and the total film thickness was taken as the average value of the inter-peak distances of the wavy structure.

<Evaluation with glass bonded products>
A glass plate having a length of 50 mm, a width of 50 mm, and a thickness of 2 mm was attached to the display member on the phase difference A side using an acrylic adhesive SK-2057 (manufactured by Soken Chemical Co., Ltd.). A projector (EB-G6250W manufactured by Seiko Epson Corporation) was placed on the glass side, and the visibility of the image was evaluated from the following viewpoints with the glass in focus. Two cases, one in which the light emitted from the projector was unpolarized and the other in which the light emitted from the projector was P-polarized, were evaluated.
A: A real image that is bright enough and has no blur is visible.
B: A bright but slightly blurred real image is visible.
C: The real image is visible, but it is dark.
D: The real image cannot be seen.

<Evaluation with laminated glass>
A PVB (polyvinyl butyral) film with a thickness of 0.38 mm manufactured by Sekisui Chemical Co., Ltd., which was cut to the same size, was placed on a glass plate having a length of 300 mm, a width of 300 mm, and a thickness of 2 mm. Was installed with the bottom surface facing the bottom surface, and a glass plate having a length of 300 mm, a width of 300 mm, and a thickness of 2 mm was installed on the glass plate. This was held at 90 ° C. and 10 kPa (0.1 atm) for 1 hour, and then heated in an autoclave (manufactured by Kurihara Seisakusho) at 115 ° C. and 1.3 Mpa (13 atm) for 20 minutes to remove air bubbles. I got a glass.
A projector (EB-G6250W, manufactured by Seiko Epson Corporation) is placed on the phase difference A side of the laminated glass produced by using the display members RS-1 to 14, and the light emitted from the projector is P-polarized. The visibility of the image was evaluated from the following viewpoints with the glass in focus.
A: A real image that is bright enough and has no blur is visible.
B: A bright but slightly blurred real image is visible.
C: The real image is visible, but it is dark.
D: The real image cannot be seen.

<Evaluation of visible light transmittance>
The transmittance of the laminated glass produced above was measured using a luminance meter BM-5A (manufactured by Topcon). The evaluation was made from the following viewpoints based on the visible light transmittance of 70% or more required for the windshield glass.
A: The visible light transmittance is 80% or more.
B: Visible light transmittance is 70% or more and less than 80%.
C: Visible light transmittance is less than 70%, which is not suitable for windshield glass.

In Comparative Example 1 of Table 4 above, R [-60,40] (550) / R [-60,30] (550) is calculated with R [-60,30] (550) being 0%. Since it is not, it is expressed as "-", and the average value of the inter-peak distances of the wavy structure is described as "-" because it does not have a wavy structure.

1 Light reflection layer 2 Orientation layer 3 Phase difference layer A
4 Support 5 Phase difference layer B
11 First resin film 12 Second resin film 13 Real image display member 21 Intermediate layer 31 First glass 32 Second glass 41 Incident light at the time of measurement 51 Reflected light at a polar angle of 40 degrees at the time of measurement 52 At the time of measurement Reflected light with a polar angle of 30 degrees

Claims (13)

It has one or more light reflection layers in which the central wavelength of selective reflection at a polar angle of 60 ° exists in the visible light region.
At least one of the light reflecting layers is formed from a cholesteric liquid crystal layer.
The spiral sense of all cholesteric liquid crystal layers is the same,
A member for displaying a real image that satisfies the following formula (1) .
A member for displaying a real image, which has a maximum reflectance of 15 to 28% of integrated reflectance at a wavelength of 620 to 680 nm .
R [-60,40] (550) / R [-60,30] (550) ≧ 1.5 Equation (1)
Here, R [-60,40] (550) is a polar angle 40 at an azimuth angle 180 ° deviated from the azimuth angle of the incident light with respect to the incident light having a polar angle of −60 ° on the real image display member. Represents the reflectance at a wavelength of 550 nm, measured at a light receiving angle of °, and R [-60,30] (550) is the incident light with respect to the incident light with a polar angle of -60 ° on the real image display member. It represents the reflectance at a wavelength of 550 nm, which is measured at a light receiving angle of a polar angle of 30 ° at an azimuth that deviates from the azimuth of. The real image display member according to claim 1, further comprising a retardation layer A composed of a λ / 2 retardation layer or a λ / 4 retardation layer. The cholesteric liquid crystal layer has a striped pattern of bright and dark areas observed by a scanning electron microscope in a cross section, and the striped pattern has a wavy structure, and the average of the peak distances of the wavy structure. The real image display member according to claim 1 or 2, wherein the value is 0.5 μm to 50 μm.
Here, the wavy structure means that at least one region M in which the absolute value of the inclination angle with respect to the plane of the cholesteric liquid crystal layer is 5 ° or more exists in the continuous line of the bright part or the dark part of the striped pattern, and the region M is sandwiched. Represents the closest point where a peak or valley with an inclination angle of 0 ° is identified.
Further, the inter-peak distance of the wavy structure is the distance in the plane direction of the cholesteric liquid crystal layer for two peaks or valleys having an inclination angle of 0 ° at the closest positions with the region M in between, and the cholesteric liquid crystal layer is measured. The length in the long axis direction of the cross section is 100 μm, and the value is arithmetically averaged over the total thickness. The real image display member according to claim 2, further comprising a retardation layer B on a surface of the light reflection layer opposite to a surface of the retardation layer A. The real image display member according to claim 4 , wherein the narrow angle formed by the slow axis of the retardation layer A and the slow axis of the retardation layer B is 40 ° to 85 °. Any one of claims 1 to 5 , including a first glass plate, a second glass plate, and an intermediate layer between the first glass plate and the second glass plate, and at least a part of the intermediate layer. A real image display member including the real image display member described in the section. The real image display member according to claim 6 , which is a windshield glass. The real image display member according to claim 6 or 7 , wherein the intermediate layer is a resin film. The real image display member according to claim 8 , wherein the resin film contains polyvinyl butyral. The real image display member according to any one of claims 1 to 9 , which is used as an in-vehicle display system. A projection image display system having a real image display member according to any one of claims 1 to 10 and a projector, and having p-polarized light in which the incident light of the projector vibrates in a direction parallel to the incident surface. The projected image display system according to claim 11 , wherein the incident light is incident on the normal line of the real image display member at an angle of 40 ° to 70 °. The projected image display system according to claim 11 or 12 , wherein the incident light is incident from below when the real image display member is used.

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