JP2018200459A - Member for real image display and display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a member for displaying a real image having a bright display image and excellent visibility, and a display system. SOLUTION: The center wavelength of selective reflection at a polar angle of 60 ° has one or more light reflection layers existing in the visible light region, and at least one of the light reflection layers is formed from a cholesteric liquid crystal layer, and all cholesterics. A member for displaying a real image that has the same spiral sense of the liquid crystal layer and satisfies the equation (1). R [-60,40] (550) / R [-60,30] (550) ≧ 1.5 equation (1). In the formula, R [-60, 40] (550) is measured by the azimuth angle with respect to the incident light at the polar angle -60 ° to the real image display member and the light receiving angle of the polar angle 40 ° at the azimuth angle deviated by 180 °. Represents the reflectance at a wavelength of 550 nm, and 30 of R [-60,30] (550) represents the light receiving angle of a polar angle of 30 ° at an azimuth angle 180 ° deviated from the azimuth angle of the incident light. [Selection diagram] None

Description

  The present invention relates to a real image display member. 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 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 simultaneously displaying a projected image and a front landscape is used. Patent Document 1 discloses that an intermediate layer is formed by sandwiching a half mirror film including a retardation layer and a plurality of cholesteric liquid crystal layers between two resin films such as a polyvinyl butyral film. In Patent Document 1, the above 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 JP-A-2015-212800

  As disclosed in Patent Document 1, a projection image display member used in a conventional head-up display system uses virtual image display. For example, the light emitted from the image display means is reflected by a projection image display member arranged on the windshield and then reaches the observer. The observer sees the image projected on the windshield, but since the image can appear to be in front of and far from the windshield, application to a car navigation system or the like is being studied. 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 the real image display, not in front and far from the windshield. It is demanded.

  As a real image display member capable of real image display, for example, Patent Document 2 describes a real image display member having a resin layer containing inorganic particles, and reflects light from the front side of the display member, It is described that light from the back side is transmitted so that the projected image and the back side scene can be viewed simultaneously.

  In such a member for displaying a real image using the scattering of inorganic particles, since the light is scattered in all directions, the displayed image can be viewed at a high angle. However, the displayed real image is dark, in particular, a windshield or the like. There is a problem that it cannot be applied when 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 visible light transmittance in the vertical direction with respect to the windshield for automobiles satisfies the legal restriction of 70% or more. I could not.

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

  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 intensive studies by the present inventors, it has been found that it is possible to obtain a bright real image display at a limited angle such as an in-vehicle environment by gently undulating the orientation state of the cholesteric liquid crystal. I found that the problem could be solved.

  That is, it has been found that the above-described problem can be achieved by the following configuration.

[1] One or more light reflecting layers having a central wavelength of selective reflection at a polar angle of 60 ° in the visible light region, and at least one of the light reflecting layers is formed of a cholesteric liquid crystal layer. A member for displaying a real image, in which the spiral sense of the layers is the same and satisfies the following formula (1).
R [−60, 40] (550) / R [−60, 30] (550) ≧ 1.5 Formula (1)
Here, R [−60, 40] (550) is polar angle 40 at an azimuth angle that is 180 ° shifted from the azimuth angle of the incident light with respect to incident light having a polar angle of −60 ° to the real image display member. R [−60, 30] (550) represents the reflectance at a wavelength of 550 nm measured at a light receiving angle of °, and R [−60, 30] (550) represents the incident light with respect to the incident light having a polar angle of −60 ° to the real image display member. The reflectance at a wavelength of 550 nm, which is measured at a light receiving angle of 30 ° polar angle at an azimuth angle that is 180 ° shifted from the azimuth angle of γ is shown.
[2] The real image display member according to [1], including 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 stripe pattern of a bright part and a dark part observed by a scanning electron microscope in a cross section, and the stripe pattern has a wavy structure, and a peak-to-peak distance of the wavy structure The real image display member according to [1] or [2], wherein an average value of is from 0.5 μm to 50 μm.
Here, the wavy structure means that there is 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 a continuous line of a bright part or a dark part in a striped pattern, and sandwiches the region M. This indicates that two peaks or valleys with an inclination angle of 0 ° at the closest positions are specified.
Further, the peak-to-peak distance of the wavy structure is the distance between the cholesteric liquid crystal layers in the plane direction of the two peaks or valleys having an inclination angle of 0 ° that are closest to each other with the region M interposed therebetween. Represents a value obtained by arithmetic averaging of 100 μm in the long axis direction of the cross section and the total film 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], further including a retardation layer B on a surface opposite to the surface having the retardation layer A of the light reflection layer.
[6] The real image display member according to [5], wherein a narrow angle formed by the slow axis of the retardation layer A and the slow axis of the phase difference B is 40 ° to 85 °.
[7] A first glass plate, a second glass plate, and an intermediate layer between the first glass plate and the second glass plate, and [1] to [6] in at least a part of the intermediate layer A real image display member comprising the real image display member according to any one of the above.
[8] The real image display member according to [7], which is windshield glass.
[9] The real image display member according to [7] or [8], wherein the intermediate layer is a resin film.
[10] The real image display member according to [9], wherein the resin film contains polyvinyl butyral.
[11] The real image display member according to any one of [1] to [10], which is used as an in-vehicle display system.
[12] A projected image display system that includes a real image display member according to any one of [1] to [11] and a projector, and is p-polarized light in which incident light of the projector vibrates in a direction parallel to the incident surface. .
[13] The projection image display system according to [12], in which incident light is incident at an angle of 40 ° to 70 ° with respect to the normal line of the projection image display member.
[14] The projection image display system according to [12] or [13], in which 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 and a display system that have a bright display image and excellent visibility.

FIG. 1 is a diagram schematically showing an example of a real image display member of the present invention. FIG. 2 is a view schematically showing an example of a laminated glass produced by the production method of the present invention. FIG. 3 is a diagram schematically showing a method for measuring the reflectance of the real image display member 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. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
In the present specification, for example, an angle such as “45 °”, “parallel”, “vertical”, or “orthogonal”, unless otherwise specified, has a difference from an exact angle within a range of less than 5 degrees. Means. The difference from the exact angle is preferably less than 4 degrees, and more preferably less than 3 degrees.
In this specification, “(meth) acrylate” is used to mean “one or both of acrylate and methacrylate”.
In this specification, “same” includes an error range generally allowed in the technical field. In addition, in the present specification, when “all”, “any” or “entire surface” is used, it includes an error range generally allowed in the technical field in addition to the case of 100%, for example, 99% or more, The case of 95% or more, or 90% or more is included.

  In this specification, “sense” for circularly polarized light means right circularly polarized light or left circularly polarized light. The sense of circularly polarized light is right-handed circularly polarized light when the electric field vector tip turns clockwise as time increases when viewed as the light travels toward you, and left when it turns counterclockwise. Defined as being circularly polarized.

  In this specification, the term “sense” may be used for the twist 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 right circularly polarized light and transmits left circularly polarized light. When the sense is left, it reflects left circularly polarized light and transmits right circularly polarized light.

Visible light is light having a wavelength visible to the human eye among electromagnetic waves, and indicates light having a wavelength range of 380 nm to 780 nm. Invisible light is light having a wavelength range of less than 380 nm or a wavelength range of more than 780 nm.
Although not limited to this, among visible light, light in the wavelength range of 420 nm to 490 nm is blue light, light in the wavelength range of 495 nm to 570 nm is green light, and 620 nm to 750 nm. The light in the wavelength band is red light. Among infrared light, near infrared light is an electromagnetic wave having a wavelength range of 780 nm to 2500 nm. Ultraviolet light is light having a wavelength in the range of 10 to 380 nm.
In this specification, the measurement of the light intensity required in connection with the calculation of the light transmittance may be performed by using, for example, a normal visible spectrum meter and measuring the reference as air.
In the present specification, the term “reflected light” or “transmitted light” is used to mean scattered light and diffracted light.

In the present invention, the integral reflectance means that a spectrophotometer (manufactured by JASCO Corp., V-550) has a large integrating sphere device (V-550) so that light enters from the viewing side surface of the target object (member). It is the value measured using what attached JASCO Corporation, ILV-471) so that regular reflection light may be included without using an optical trap.
As for the selective reflection wavelength, when the reflection spectrum of the reflection region is measured by the above-described method, a characteristic reflectance waveform having a mountain shape (convex shape upward) with the wavelength as the horizontal axis is obtained. At this time, the average reflectance (arithmetic mean) of the maximum value and the minimum value of the characteristic reflectance is obtained, and among the two wavelengths at the intersection of the waveform and the average reflectance, the wavelength value on the short wave side is λA (nm), and the long wave The wavelength value on the side is λB (nm), and is a value calculated by the following formula.
Peak wavelength of characteristic reflection = (λA + λB) / 2
Further, “equal” for the selective reflection wavelengths of a plurality of objects does not mean that they are strictly equal, and an error in a range that does not affect optically is allowed. Specifically, the selective reflection wavelengths of a plurality of objects are “equal”, which 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, More preferably, it is 10 nm or less.

In addition, the polarization state of each wavelength of light can be measured using a spectral radiance meter or a spectrometer equipped with a circularly 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. Moreover, even if a circularly polarizing plate is attached to an illuminometer or a spectrum meter, the measurement can be performed. The ratio can be measured by attaching a right circular polarized light transmission plate, measuring the right circular polarized light amount, attaching a left circular polarized light transmission plate, and measuring the left circular polarized light amount.

In this specification, p-polarized light means polarized light that vibrates in a direction parallel to the light incident surface. The incident surface means a surface that is perpendicular to the reflecting surface (such as the laminated glass surface) and includes the incident light beam and the reflected light beam. In p-polarized light, the vibration plane of the electric field vector is parallel to the incident plane. In this specification, s-polarized light means polarized light that vibrates in a direction perpendicular to the light incident surface.
In this specification, Re (550) means in-plane retardation (nm) at a wavelength of 550 nm, and Rth (550) means retardation in the thickness direction (nm) at a wavelength of 550 nm. As a measuring method of Re (550) and Rth (550), it can measure with phase difference measuring apparatuses, such as KOBRA 21ADH or WR (made by Oji Scientific Instruments), AXOSCAN (made by AXOMETRICS). The measurement wavelength is 550 nm unless otherwise specified.

<< Real image display member >>
The real image display member of the present invention is
Having 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,
Satisfies the following formula (1), and
Of the reflective layers, at least one is formed from a cholesteric liquid crystal layer,
This is a real image display member in which all the cholesteric liquid crystal layers have the same spiral sense.
R [−60, 40] (550) / R [−60, 30] (550) ≧ 1.5 Formula (1)
Here, R [−60, 40] (550) is a polar angle of 40 ° at an azimuth angle that is 180 ° shifted from the azimuth angle of the incident light with respect to the incident light having a polar angle of −60 ° to the display member. R [−60, 30] (550) represents the reflectance at a wavelength of 550 nm, measured at the light receiving angle, and the direction 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 30 ° polar angle at an azimuth angle that is 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 the real image display member 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 may include the alignment layer 2 for the purpose of adjusting the alignment 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. Although not shown in FIG. 1, the real image display member of the present invention may be produced using a peelable support.

The real image display member includes a retardation layer and a light reflection 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, a projected image display part can be formed on a glass plate or laminated glass.
Hereinafter, the glass plate or the laminated glass may be collectively referred to simply as a glass plate or glass.

In this specification, the projected image display part is a part capable of displaying a projected image with reflected light, and may be any part capable of displaying the projected image projected from a projector or the like so as to be visible.
When a glass plate is used in a real image display system, an image projected from a projector can be displayed in a visible portion of the functional layer, and when the functional layer is observed from the same side where the image is displayed, Information or scenery on the opposite side can be observed simultaneously.

  In the aspect in which the real image display member is used by being bonded to the glass plate, the real image display member may be on the entire surface of the glass plate, or may be a part of the entire area of the glass plate. When 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, 10% or more. In addition, when it is a part, the real image display member may be provided at any position on the glass plate. However, when used as a head-up display system, the image is displayed at a position that can be easily seen by an observer (for example, a 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, it is preferably arranged at a position below the center of the glass plate.

In the glass plate, the real image display member may have a flat shape that does not have a curved surface, but may have a curved surface, and has a concave or convex shape as a whole, and enlarges the projected image. Alternatively, the display may be reduced.
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 an embodiment having no support, it is preferably 20 μm or less, and more preferably 15 μm or less.

  The real image display member may be any member as long as it has a function as a half mirror for at least the projection light. However, for example, it does not need to function as a half mirror for light in the entire visible light range. In addition, the real image display unit only needs to have the above-described function with respect to light having at least a part of incident angles.

  In an embodiment in which the real image display member is used by being bonded to a glass plate, it is preferable that the real image display member has visible light transparency so as to enable observation of information or scenery on the opposite surface side. The real image display portion may have a light transmittance of 40% or more, preferably 50% or more, more preferably 60% or more, and further preferably 70% or more in the visible light wavelength region. If the visible light transmittance is 70% or more, it can be arbitrarily used in the entire region of the windshield for automobiles. The light transmittance is the light transmittance determined by the method described in JIS-K7105.

The real image display member may include a layer including a cholesteric liquid crystal structure and a phase difference layer, an alignment layer, an adhesive layer, a base layer, a transparent layer, and the like.
The real image display member used for glass bonding or laminated glass production may be a film shape, a sheet shape, or a plate shape. The real image display member may be formed in a roll or the like as a thin film, and thereafter used for glass bonding or production of laminated glass.

[Layer containing cholesteric liquid crystal structure]
In the real image display member, one or more layers including a cholesteric liquid crystal structure may be included. Between the layers containing two or more cholesteric liquid crystal structures, other layers such as an alignment layer and an adhesive layer may be included. Further, other layers such as a base layer and 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 any structure as long as the orientation of the liquid crystal compound in the cholesteric liquid crystal phase is maintained. Typically, the polymerizable liquid crystal compound is placed in the orientation state of the cholesteric liquid crystal phase and then irradiated with ultraviolet rays. Any structure may be used as long as it is polymerized and cured by heating or the like and has no fluidity, and at the same time, the structure does not change the orientation form due to 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 may no longer exhibit liquid crystallinity. For example, the polymerizable liquid crystal compound may have a high molecular weight due to a curing reaction and may no longer have liquid crystallinity.

It is known that the cholesteric liquid crystal phase exhibits circularly polarized light selective reflection that selectively reflects the circularly polarized light of either the right circularly polarized light or the left circularly polarized light and transmits the circularly polarized light of the other sense. In this specification, the circularly polarized light selective reflection is sometimes simply referred to as selective reflection.
As a film including a layer in which a cholesteric liquid crystal phase exhibiting circularly polarized light selective reflection is fixed, many films formed from a composition containing a polymerizable liquid crystal compound have been conventionally known. Regarding a cholesteric liquid crystal structure or a cholesteric liquid crystal layer, The prior art can be referred to.

  The central wavelength λ of selective reflection of the cholesteric liquid crystal structure depends on the pitch P (= helical period) of the helical structure in the cholesteric phase, and follows the relationship between the average refractive index n of the cholesteric liquid crystal structure and λ = n × P. In the present specification, the selective reflection center wavelength λ of the cholesteric liquid crystal structure means a 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 helical structure. The cholesteric liquid crystal layer exhibiting selective reflection in the visible light region preferably has a center wavelength of selective reflection in the visible light region. By adjusting the n value and the P value, for example, the center wavelength λ is adjusted to selectively reflect either the right circularly polarized light or the left circularly polarized light with respect to red light, green light, and blue light. be able to.

The real image display member of the present invention does not produce a clear double image as in the embodiment using a virtual image, but diffuse reflection occurs when light reflected from the front or back surface is incident on the real image display member again. As a result, image blur occurs and sharpness decreases. For this reason, in a mode of being used by being bonded to a glass plate like a head-up display system, a cholesteric liquid crystal structure is used to reduce image blur caused by reflection of projection light on the front or back surface of the glass plate. It is preferable to use a glass plate so that light is incident obliquely with respect to the containing layer. Further, in this way, when light is incident obliquely, the center wavelength of 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 formula of λ = n × P is on the long wavelength side with respect to the wavelength of selective reflection required for the projected image display. preferable. The center of selective reflection when a light ray passes through an angle of θ ₂ with respect to the normal direction of the layer containing the cholesteric liquid crystal structure (the helical axis direction of the cholesteric liquid crystal layer) in the layer containing the cholesteric liquid crystal structure having a refractive index n 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 a layer including a cholesteric liquid crystal structure, an angle of 45 ° to 70 ° with respect to a normal line of a projected image display portion in air having a refractive index of 1 The light incident from the phase difference A side having a λ / 2 phase difference in the normal direction has a refractive index of about 1.45 to 1.80. Transmits at an angle of ° and enters a cholesteric liquid crystal layer having a refractive index of about 1.61. Since light passes through the cholesteric liquid crystal layer at an angle of 26 ° to 36 °, n × P may be adjusted by inserting this angle and the center wavelength of the desired selective reflection into the above equation.
Since the pitch of the cholesteric liquid crystal phase depends on the type of chiral agent used together with the polymerizable liquid crystal compound or the concentration of the chiral agent, the desired pitch can be obtained by adjusting these. For the method of measuring spiral sense and pitch, use the methods described in “Introduction to Liquid Crystal Chemistry Experiments”, edited by the Japanese Liquid Crystal Society, Sigma Publishing 2007, page 46, and “Liquid Crystal Handbook”, Liquid Crystal Handbook Editing Committee, page 196. be able to.

  By adjusting the central wavelength of 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 projection is efficient and clear. Video can be displayed. In particular, by adjusting the central wavelength of selective reflection of each cholesteric liquid crystal structure according to the emission wavelength range of the light source used for projection, a clear color projection image can be displayed with high light utilization efficiency. Examples of usage of the layer including the cholesteric liquid crystal structure include an incident angle of projection light onto the layer including the cholesteric liquid crystal structure, a direction in which the projected image is observed, and the like.

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

The full width at half maximum Δλ (nm) of the selective reflection band showing selective reflection depends on the relationship of Δλ = Δn × P, where Δλ depends on the birefringence Δn of the liquid crystal compound and the pitch 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 alignment fixation.
The half width Δλ of 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 a liquid crystal compound fixed in a cholesteric alignment state. The cholesteric alignment state may include both an alignment state that reflects right circularly polarized light and an alignment state that reflects left circularly polarized light. The liquid crystalline compound used in the present invention is not particularly limited, and various known compounds can be used.

In addition, the cholesteric liquid crystal layer used in the present invention preferably has a striped pattern of a bright part and a dark part when the cross section is observed using a scanning electron microscope (SEM).
The striped pattern preferably has a corrugated structure, and the average value of the peak-to-peak distance of the corrugated structure is preferably 0.5 μm to 50 μm. The thickness is more preferably 1.5 μm to 30 μm, and further preferably 2.5 μm to 20 μm.

  In the present invention, the wavy structure means that there is 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 or dark portion of the striped pattern. It means that two peaks or valleys with an inclination angle of 0 ° located at the closest position are specified.

  A peak or valley having an inclination angle of 0 ° includes a convex shape and a concave shape, but if the inclination angle is 0 °, it includes a stepped shape and a shelf-shaped point. In the undulating structure, it is preferable that a region M where the absolute value of the inclination angle is 5 ° or more in a continuous line of bright or dark portions in a striped pattern and a plurality of peaks or valleys sandwiching the region M are repeated.

  Further, the peak-to-peak distance of the wavy structure is the distance between the cholesteric liquid crystal layers in the plane direction of the two peaks or valleys having an inclination angle of 0 ° that are closest to each other with the region M interposed therebetween. This is a value obtained by arithmetically averaging the length in the longitudinal direction of the cross section of 100 μm and the total film thickness.

  Here, when each continuous line is in contact with either interface of the film and is interrupted, both ends of the interrupted portion are not regarded as peaks or valleys. In addition, 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 for producing cholesteric liquid crystal structure)
Hereinafter, a manufacturing material and a manufacturing method of 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, apply or drop droplets of the above liquid crystal composition, which is mixed with a surfactant or a polymerization initiator and dissolved in a solvent, onto the lower retardation layer, underlayer, cholesteric liquid crystal layer, etc. After alignment 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 by coating, and a layer containing a plurality of cholesteric liquid crystal dots can be produced by droplet ejection.

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

  The polymerizable liquid crystal compound can be obtained by introducing a polymerizable group into the liquid crystal compound. Examples of the polymerizable group include an unsaturated polymerizable group, an epoxy group, and an aziridinyl group, preferably an unsaturated polymerizable group, and particularly preferably an ethylenically unsaturated polymerizable group. The polymerizable group can be introduced into the molecule of the liquid crystal compound by various methods. The number of polymerizable groups possessed by the polymerizable liquid crystal compound is preferably 1-6, more preferably 1-3, per molecule. Examples of polymerizable liquid crystal compounds are described in Makromol. Chem. 190, 2255 (1989), Advanced Materials 5, 107 (1993), US Pat. Nos. 4,683,327, 5,622,648 and 5,770,107, International Publication WO95 / 22586, International Published WO 95/24455, WO 97/00600, WO 98/23580, WO 98/52905, JP-A-1-272551, JP-A-6-16616, JP-A-7-110469, JP-A-11-80081, JP-A-2001-2001 The compounds described in Japanese Patent No. 328973, WO2016 / 194327, WO2016 / 052367 and the like are included. Two or more kinds of polymerizable liquid crystal compounds may be used in combination. When two or more kinds of polymerizable liquid crystal compounds are used in combination, the alignment temperature may be lowered.

  Moreover, it is preferable that the addition amount of the polymeric liquid crystal compound in a liquid-crystal composition is 80-99.9 mass% with respect to solid content mass (mass except a solvent) of a liquid-crystal composition, and 85-99. More preferably, it is 5 mass%, and it is especially preferable that it is 90-99 mass%.

(Chiral agent: optically active compound)
The chiral agent has a function of inducing a helical structure of a cholesteric liquid crystal phase. The chiral compound may be selected according to the purpose because the helical sense or helical pitch induced by the compound is different.
There is no restriction | limiting in particular as a chiral agent, A well-known compound can be used. Examples of chiral agents include liquid crystal device handbook (Chapter 3-4, TN, chiral agent for STN, 199 pages, edited by Japan Society for the Promotion of Science, 142nd Committee, 1989), JP-A 2003-287623, Examples thereof include compounds described in JP-A No. 2002-302487, JP-A No. 2002-80478, JP-A No. 2002-80851, JP-A No. 2010-181852 or JP-A No. 2014-034581.

A chiral agent generally contains an asymmetric carbon atom, but an axially asymmetric compound or a planar asymmetric compound containing no asymmetric carbon atom can also be used as the chiral agent. Examples of the axial asymmetric compound or the planar asymmetric compound include binaphthyl, helicene, paracyclophane, and derivatives thereof. The chiral agent may have a polymerizable group. When both the chiral agent and the liquid crystal compound have a polymerizable group, they are derived from the repeating unit derived from the polymerizable liquid crystal compound and the chiral agent by a polymerization reaction between the polymerizable chiral agent and the polymerizable liquid crystal compound. A polymer having repeating units can be formed. In this aspect, the polymerizable group possessed by the polymerizable chiral agent is preferably the same group as the polymerizable group possessed by the polymerizable liquid crystal compound. Therefore, the polymerizable group of the chiral agent is also preferably an unsaturated polymerizable group, an epoxy group or an aziridinyl group, more preferably an unsaturated polymerizable group, and an ethylenically unsaturated polymerizable group. Particularly preferred.
The chiral agent may be a liquid crystal compound.

As the chiral agent, an isosorbide derivative, an isomannide derivative, or a binaphthyl derivative can be preferably used. As the isosorbide derivative, commercially available products 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 advanced by ultraviolet irradiation, the polymerization initiator to be used is preferably a photopolymerization initiator that can start the polymerization reaction by ultraviolet irradiation. Examples of the photopolymerization initiator include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in US Pat. No. 2,448,828), α-hydrocarbon substituted aromatics. Group acyloin compounds (described in US Pat. No. 2,722,512), polynuclear quinone compounds (described in US Pat. Nos. 3,046,127 and 2,951,758), combinations of triarylimidazole dimers and p-aminophenyl ketone (US patents) No. 3549367), acridine and phenazine compounds (JP-A-60-105667, US Pat. No. 4,239,850), acylphosphine oxide compounds (JP-B 63-40799, JP-B-5) No. 29234, Japanese Patent Laid-Open No. 10-95788 JP, 10-29997, JP 2001-233842, JP 2000-80068, JP 2006-342166, JP 2013-114249, JP 2014-137466, Japanese Patent No. 4223071, Japanese Patent Application Laid-Open No. 2010-262028, Japanese Patent Publication No. 2014-500852), an oxime compound (Japanese Patent Application Laid-Open No. 2000-66385, Japanese Patent No. 4454067), and an oxadiazole compound ( U.S. Pat. No. 4,221,970). For example, description of paragraph 0500-0547 of Unexamined-Japanese-Patent No. 2012-208494 can also be considered.

As the polymerization initiator, it is also preferable to use an acyl phosphine oxide compound or an oxime compound.
As the acylphosphine oxide compound, for example, IRGACURE 810 (compound name: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide) manufactured by BASF Japan Ltd. can be used. As oxime compounds, IRGACURE OXE01 (manufactured by BASF), IRGACURE OXE02 (manufactured by BASF), TR-PBG-304 (manufactured by Changzhou Power Electronics New Materials Co., Ltd.), Adeka Arcles NCI-831, Adeka Arcles NCI-930 Commercial products such as (ADEKA) and Adeka Arcles NCI-831 (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, and preferably 0.5% by mass to 5% by mass with respect to the content of the polymerizable liquid crystal compound. More preferably.

(Crosslinking agent)
The liquid crystal composition may optionally contain a crosslinking agent in order to improve the film strength after curing and improve the durability. As the cross-linking agent, those that can be cured by ultraviolet rays, heat, moisture and the like can be suitably used.
There is no restriction | limiting in particular as a crosslinking agent, According to the objective, it can select suitably, For example, polyfunctional acrylate compounds, such as a trimethylol propane tri (meth) acrylate and pentaerythritol tri (meth) acrylate; Glycidyl (meth) acrylate , Epoxy compounds such as ethylene glycol diglycidyl ether; aziridine compounds such as 2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], 4,4-bis (ethyleneiminocarbonylamino) diphenylmethane; hexa Isocyanate compounds such as methylene diisocyanate and biuret type isocyanate; polyoxazoline compounds having an oxazoline group in the side chain; vinyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylto Alkoxysilane compounds such as methoxy silane. Moreover, a well-known catalyst can be used according to the reactivity of a crosslinking agent, and productivity can be improved in addition to membrane strength and durability improvement. These may be used individually by 1 type and may use 2 or more types together.
3 mass%-20 mass% are preferable, and, as for content of a crosslinking agent, 5 mass%-15 mass% are more preferable. By making the content of the crosslinking agent 3% by mass or more, an effect of improving the crosslinking density can be obtained, and by making the content of the crosslinking agent 20% by mass or less, the stability of the cholesteric liquid crystal structure is lowered. Can be prevented.

(Orientation control agent)
In the liquid crystal composition, an alignment control agent that contributes to stably or rapidly form a cholesteric liquid crystal structure with planar alignment may be added. Examples of the orientation control agent include fluorine (meth) acrylate polymers described in paragraphs [0018] to [0043] of JP-A-2007-272185, and paragraphs [0031] to [0034] of JP-A-2012-203237. Etc.] and the compounds represented by the formulas (I) to (IV).
In addition, as an orientation control agent, 1 type may be used independently and 2 or more types may be used together.

  The addition amount of the alignment control agent in the liquid crystal composition is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 5% by mass with respect to 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 alignment control agent that contributes to stable or rapid conversion to a planar cholesteric structure. Examples of the surfactant include a silicone-based surfactant and a fluorine-based surfactant, and a fluorine-based surfactant is preferable.

  Specific examples of the surfactant include compounds described in JP-A-2014-119605, [0082] to [0090], compounds described in paragraphs [0031] to [0034] of JP-A-2012-203237, Compounds exemplified in [0092] and [0093] of JP-A-2005-99248, exemplified in [0076] to [0078] and [0082] to [0085] of JP-A-2002-129162 And fluorine (meth) acrylate polymers described in paragraphs [0018] to [0043] of JP-A-2007-272185, and the like.

  In addition, as a horizontal alignment agent, 1 type may be used independently and 2 or more types may be used together.

  As the fluorine-based surfactant, a compound represented by the following general formula (I) described in JP-A-2014-119605, [0082] to [0090] is particularly preferable.

In the general formula (I), L ¹¹ , L ¹² , L ¹³ , L ¹⁴ , L ¹⁵ , and L ¹⁶ are each independently a single bond, —O—, —S—, —CO—, —COO—, — 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 production. Therefore, preferably -O-, -S-, -CO-, -COO-, -OCO-, -COS-, and -SCO-, and more preferably -O-, from the viewpoint of the stability of the compound. -CO-, -COO-, and -OCO-. The alkyl group that R can take may be linear or branched. As for carbon number, 1-3 are more preferable, and a methyl group, an ethyl group, and n-propyl group can be illustrated.

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 further 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 be branched, but a linear alkylene group having no branch is preferred. From the viewpoint of synthesis, 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 4 valent aromatic hydrocarbon groups. 6-22 are preferable, as for carbon number of an aromatic hydrocarbon group, 6-14 are more preferable, 6-10 are more preferable, and 6 is especially preferable. 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 for 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. A molecule having a large number of perfluoroalkyl moieties in the molecule can orient the liquid crystal with a small addition amount, leading to a decrease in haze. Therefore, A ¹¹ and A ¹² have a large number of perfluoroalkyl groups in the molecule. It is preferable that it is tetravalent. From the viewpoint of synthesis, A ¹¹ and A ¹² are preferably the same.

T ¹¹ represents the following divalent group or divalent aromatic heterocyclic group (X included in T ¹¹ is an alkyl group having 1 to 8 carbon atoms, an alkoxy group, a halogen atom, or a cyano group. Or 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 these, more preferable groups are shown below.

More preferably, they are the following groups.

Most preferably, they are the following groups.

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

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. Examples of the ester group that X contained in T ¹¹ can take include a group represented by R ^a COO—. Examples of ^Ra include an alkyl group having 1 to 8 carbon atoms. For the explanation and preferred range of the alkyl group that R ^a can take, reference can be made to the explanation and preferred range of the alkyl group that X contained in T ¹¹ can take. Specific examples of the ester include CH ₃ COO— and C ₂ H ₅ COO—. The alkyl group 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 heterocyclic ring. A 5-membered ring or a 6-membered ring is more preferable, and a 6-membered ring is most preferable. As the hetero atom constituting the heterocyclic ring, a nitrogen atom, an oxygen atom or a sulfur atom is preferable. The heterocycle is preferably an aromatic heterocycle. The aromatic heterocycle is generally an unsaturated heterocycle. An unsaturated heterocyclic ring having the most double bond is more preferable. Examples of heterocyclic rings include furan ring, thiophene ring, pyrrole ring, pyrroline ring, pyrrolidine ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, imidazoline ring, imidazolidine ring, pyrazole ring, pyrazoline Ring, pyrazolidine ring, triazole ring, triazane ring, tetrazole ring, pyran ring, thiyne ring, pyridine ring, piperidine ring, oxazine ring, morpholine ring, thiazine ring, pyridazine ring, pyrimidine ring, pyrazine ring, piperazine ring and triazine ring included. The divalent heterocyclic group may have a substituent. For the explanation and preferred range of examples of such substituents, the explanation and description regarding the substituents that can be taken by the above-mentioned A ¹¹ and A ¹² 1 to 4 valent aromatic hydrocarbons 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 still more preferably a perfluoroalkyl group having 3 to 10 carbon atoms. The perfluoroalkyl group may be linear, branched or cyclic, but is preferably linear or branched, and more preferably linear.

m11 and n11 are each independently 0 to 3, and m11 + n11 ≧ 1. In this case, a plurality of parenthesized structures may be the same or different, but are preferably 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.}

O and p included in T ¹¹ are each independently an integer of 0 or more, and when o and p are 2 or more, a plurality of X may be the same or different from each other. O contained in the T ¹¹ is preferably 1 or 2. P is preferably an integer of 1 to 4 contained in the T ^11, 1 or 2 is more preferred.

  The compound represented by the general formula (I) may have a symmetrical molecular structure or may have no 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, or rotational symmetry. Means things.

The compound represented by the general formula (I), the above-mentioned perfluoroalkyl group ^{(Hb 11),} the 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 present in the molecule-(-Sp ¹¹ -L ¹¹ -Sp ¹² -L ¹² ) m11-A ¹¹ -L ¹³ - and ^-L 14 ^-A 12 ^- is preferably n11- also identical to each other ^{- (L 15 -Sp 13 -L 16} -Sp 14). 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 still more preferably 3 to 10. b is preferably 0 to 20, more preferably 0 to 10, and still more preferably 0 to 5. a + b is 3-30. 1-10 are preferable and, as for r, 1-4 are more preferable.

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 these 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 formula are the same as the definitions immediately above.

  The addition amount of the surfactant in the liquid crystal composition is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 5% by mass with respect to 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 a polymerizable monomer. In addition, a polymerization inhibitor, an antioxidant, an ultraviolet absorber, a light stabilizer, a colorant, metal oxide fine particles, etc. are added to the liquid crystal composition as necessary, as long as optical performance is not deteriorated. can do.

  The cholesteric liquid crystal structure is composed of a liquid crystal composition in which a polymerizable liquid crystal compound, a chiral agent and a polymerization initiator, and a surfactant added as necessary are dissolved in a solvent, a retardation layer, an underlayer, or first. It is applied or sprayed onto the prepared cholesteric liquid crystal layer, etc., and dried to obtain a coating film. The coating film is irradiated with actinic rays to polymerize the cholesteric liquid crystal composition, and the cholesteric regularity is fixed. A cholesteric liquid crystal structure can be formed. In addition, the laminated film which consists of a some cholesteric liquid crystal layer can be formed by repeating the said manufacturing process of a cholesteric liquid crystal layer.

(solvent)
There is no restriction | limiting in particular as a solvent used for preparation of a liquid-crystal composition, Although it can select suitably according to the objective, An organic solvent is used preferably.
The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. For example, ketones, alkyl halides, amides, sulfoxides, heterocyclic compounds, hydrocarbons, esters, ethers, etc. Is mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, ketones are particularly preferable in consideration of environmental load.

(Coating, orientation, polymerization)
The application method of the liquid crystal composition is not particularly limited and can be appropriately selected depending on the 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, a die Examples thereof 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 a liquid crystal composition separately coated on a support. It is also possible to eject liquid crystal compositions. As the hitting method, an ink jet method can be used.
By heating the applied or ejected liquid crystal composition, the liquid crystal molecules are aligned. The heating temperature is preferably 200 ° C. or lower, and more preferably 130 ° C. or lower. By this alignment treatment, a structure is obtained in which the polymerizable liquid crystal compound is twisted and aligned so as to have a helical axis in a direction substantially perpendicular to the film surface.

The liquid crystal composition can be cured by further polymerizing the aligned liquid crystal compound. The polymerization may be either thermal polymerization or photopolymerization utilizing light irradiation, but photopolymerization is preferred. 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 accelerate the photopolymerization reaction, light irradiation may be performed under heating conditions or in a nitrogen atmosphere. The irradiation ultraviolet wavelength is preferably 350 nm to 430 nm. The polymerization reaction rate is preferably as high as possible from the viewpoint of stability, 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 this specification, a cholesteric liquid crystal layer means a layer in which a cholesteric liquid crystal phase is fixed. A cholesteric liquid crystal layer means a layer in which a cholesteric liquid crystal structure is continuously formed in a layered manner, and is a layer showing substantially the same optical characteristics at any position of the layer.
For the cholesteric liquid crystal layer and the functional layer including a 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. For example, the real image display member may include two, three, or four cholesteric liquid crystal layers. In particular, it is preferable to include two cholesteric liquid crystal layers. For example, using a cholesteric liquid crystal layer, which is a broadband selective reflection layer exhibiting selective reflection in the red wavelength range and the green wavelength range, or in the green wavelength range and the blue wavelength range, a full color display is also realized with two cholesteric liquid crystal layers. be able to.

In the aspect in which the real image display member includes the retardation layer, the cholesteric liquid crystal layer is preferably provided directly on another layer. By providing an alignment layer obtained by coating and curing a non-liquid crystalline composition containing a (meth) acrylate monomer on the surface of the retardation layer, and forming one of the cholesteric liquid crystal layers on the surface, the projected image is a real image It is possible to provide a laminated film capable of producing a glass bonded product or a laminated glass that functions as a projection image display member.
When a cholesteric liquid crystal layer is formed on the surface of the alignment layer, the in-plane alignment direction of the liquid crystal in contact with the alignment layer is random due to the physical properties of the alignment layer. Therefore, a cholesteric liquid crystal layer formed by applying a liquid crystal composition on the surface of the alignment layer can be used as a layer having alignment defects. When a cholesteric liquid crystal layer is formed on a liquid crystal layer having alignment defects, a layer having alignment defects can be formed in the same manner. As a result, the cholesteric liquid crystal layer can be a diffuse reflective layer, and a real image display can be performed. Regarding the diffusely reflective cholesteric liquid crystal layer, reference can be made to JP-A-2006-004211 and WO2015 / 025909.

[Layer containing multiple cholesteric liquid crystal dots]
Cholesteric liquid crystal dots are formed by depositing a liquid crystal composition that expresses a cholesteric structure directly on the retardation layer or on the surface of the alignment layer, for example, by an inkjet method, and then drying, aligning, and curing as described above. It has been made. This dot is preferably formed such that the cholesteric liquid crystal dot includes a portion where the height continuously increases from the end of the cholesteric liquid crystal dot toward the center to the maximum height of the cholesteric liquid crystal dot. 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 a layer containing a plurality of cholesteric liquid crystal dots, the description in WO2016 / 194327 can be referred to.

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

[Phase difference layer]
The real image display member may include a retardation layer. In the real image display member of the present invention, the retardation layer is disposed so as to be between the support and the layer containing the cholesteric liquid crystal structure. There is also an aspect in which a member for peeling off the support is used as a real image display member. By using a retardation layer with an appropriately adjusted front retardation in combination with the layer containing the cholesteric liquid crystal structure, higher brightness can be given, and image blurring can be prevented by suppressing reflection of glass or the like. 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 a thinner layer can be obtained. The retardation layer may be a film in which a polymerizable liquid crystal compound is uniaxially aligned and fixed in alignment. The retardation layer is formed from a layer in which a liquid crystal composition containing a polymerizable liquid crystal compound is applied to the support surface or the alignment film surface. The polymerizable liquid crystal compound in the applied liquid crystal composition can be formed into a nematic alignment 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 formation of the cholesteric liquid crystal layer except that no chiral agent is added to the liquid crystal composition. However, at the time of nematic alignment 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 support surface or the alignment film surface to form a nematic alignment in a liquid crystal state and then fixing the alignment by cooling. May be.

  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, a layer having a retardation therebetween, or the like can be used as appropriate. As the retardation layer, it is preferable to use a λ / 4 retardation layer or a λ / 2 retardation layer.

  The front phase difference of the λ / 2 retardation layer may be a length that is ½ of the visible light wavelength region, or “center wavelength × n ± ½ of the center wavelength (n is an integer)”. In particular, the reflection wavelength of a layer including a cholesteric liquid crystal structure (for example, any cholesteric liquid crystal) or a length that is ½ of the center wavelength of the light 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 is preferably in the range of 200 nm to 410 nm.

  The front phase difference of the λ / 4 retardation layer may be ¼ of the visible light wavelength region, or “center wavelength × n ± ¼ of the center wavelength (n is an integer)”. In particular, the reflection wavelength of a layer containing a cholesteric liquid crystal structure (for example, any cholesteric liquid crystal) or the length of ¼ of the center wavelength of the light 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 is preferably in the range of 110 nm to 210 nm.

  In the aspect 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 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 helix. For example, the incident light is in the lower (vertically lower) direction of the projected image display region and is from the λ / 2 phase difference layer side with respect to the layer including the cholesteric liquid crystal structure (in this specification, “from the observer side”) In the case of incidence, 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 portion. preferable. Further, it is preferable that the slow axis direction is set as follows according to the spiral sense of the cholesteric liquid crystal layer in the layer containing the cholesteric liquid crystal structure. When the sense is on the right (preferably when the senses of all cholesteric liquid crystal layers are on the right), the slow axis of the λ / 2 retardation layer is from the observer side with respect to the vertical upward direction of the projected image display portion. When viewed clockwise, it is preferably in the range of 40 ° to 65 °, preferably 45 ° to 60 °. When the sense is on the left (preferably, 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 vertical upward direction of the projected image display area. Thus, it is preferable to be in the range of 40 ° to 65 °, preferably 45 ° to 60 ° in a counterclockwise direction.

  In the aspect 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 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 helix. For example, the incident light is in the lower (vertically lower) direction of the projected image display part and is from the λ / 4 phase difference layer side with respect to the layer including the cholesteric liquid crystal structure (in this specification, “from the observer side”) In the case of incidence, 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 portion. preferable. Further, it is preferable that the slow axis direction is set as follows according to the spiral sense of the cholesteric liquid crystal layer in the layer containing the cholesteric liquid crystal structure. When the sense is on the right (preferably when the senses of all cholesteric liquid crystal layers are on the right), the slow axis of the λ / 4 retardation layer is from the observer side with respect to the vertical upward direction of the projected image display portion. When viewed clockwise, it is preferably in the range of 130 ° to 160 °, preferably 130 ° to 150 °. When the sense is on the left (preferably, 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 vertical upward direction of the projected image display area. Thus, it is preferably in the range of 130 ° to 160 °, preferably 130 ° to 150 ° counterclockwise.

  In the aspect having the retardation layer B in addition to the retardation layer A, both the retardation A and the retardation B are preferably λ / 4 retardation layers or λ / 2 retardation layers. The slow axis of phase difference A and phase difference B is set as described above for the slow axis of phase difference A, and the narrow angle formed by the slow axes of the two phase differences is 40 °. It is preferable to arrange the slow axis of the phase difference B so as to be ˜85 °.

In the aspect which processes the real image display member of this invention into a laminated glass, it may be preferable to have a phase difference layer on both surfaces of a light reflection layer. Image blurring can be further prevented by having retardation layers on both sides of the light reflecting layer. In particular, it is possible to further prevent image blurring when a projected image is formed by entering p-polarized light. The effect is more remarkable when a low Δn polymerizable liquid crystal compound is used for forming a cholesteric liquid crystal layer in a layer containing a 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 of a wavelength not in the selective reflection band of the cholesteric liquid crystal layer included in the layer containing the cholesteric liquid crystal structure is cholesteric liquid crystal It is presumed that 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 incidence on the light reflection layer.
1. 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 may be noticeable, may be more noticeable at 1 mm or more, and may be more noticeable at 1.5 mm or more; It can be particularly prominent at 0 mm or more.

<Support or peelable support>
The real image display member of the present invention may include a support. For the production of the real image display member of the present invention, a peelable support may be used. The peelable support is peeled off at the time of glass bonding or during the production of an interlayer film or laminated glass.
Examples of the support or peelable support include plastic films such as polyester such as polyethylene terephthalate (PET), polycarbonate, acrylic resin, epoxy resin, polyurethane, cycloolefin resin, polyamide, polyolefin, cellulose derivative, and silicone.
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 non-uniform functional layer can be obtained when the peelable support as a base material in 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 more preferably 300 μm or less.

  The peelable support is preferably a layer that has been rubbed. The phase difference layer should just be formed by apply | coating the liquid-crystal composition to the rubbing process surface. The rubbing treatment can be performed by rubbing the surface of the peelable support (the surface of the alignment layer when an alignment layer is provided) in a certain direction with paper or cloth.

The support or peelable support may include an alignment layer. The alignment layer is a lower layer to which the liquid crystal composition is applied in the formation of the retardation layer. In the real image display member of the present invention, the support or the peelable support is in direct contact with the retardation layer. As long as it is included.
The alignment layer has a rubbing treatment of organic compounds such as polymers (resins such as polyimide, polyvinyl alcohol, polyester, polyarylate, polyamideimide, polyetherimide, polyamide, modified polyamide), oblique deposition of inorganic compounds, and microgrooves. It can be provided by means such as formation of a layer or accumulation of an organic compound (for example, ω-tricosanoic acid, dioctadecylmethylammonium chloride, methyl stearylate) using the Langmuir-Blodgett method (LB film). Further, an alignment layer that generates an alignment function by application of an electric field, application of a magnetic field, or light irradiation 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 as necessary.
The adhesive layer may be provided between the cholesteric liquid crystal layer, 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. The adhesive layer preferably has low birefringence, and preferably has a small difference in refractive index from the average refractive index (in-plane average refractive index) of the cholesteric liquid crystal layer.

The adhesive layer may be formed from an adhesive.
Adhesives include hot melt type, thermosetting type, photocuring type, reactive curing type, and pressure-sensitive adhesive type that does not require curing, from the viewpoint of curing method, and the materials are acrylate, urethane, urethane acrylate, epoxy , Epoxy acrylate, polyolefin, modified olefin, polypropylene, ethylene vinyl alcohol, vinyl chloride, chloroprene rubber, cyanoacrylate, polyamide, polyimide, polystyrene, polyvinyl butyral, etc. can do. From the viewpoint of workability and productivity, the photo-curing type, particularly the ultraviolet curing type, is preferable as the curing method, and from the viewpoint of optical transparency and heat resistance, the material is acrylate, urethane acrylate, epoxy acrylate, etc. It is preferable to do.

  The thickness of the adhesive layer in the above example is preferably 0.5 μm to 25 μm, and more preferably 1.0 μm to 5.0 μm. In order to reduce color unevenness and the like of the projected image display part, it is preferable to provide the uniform thickness.

The adhesive layer may be formed 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 image display unit surface of the image display device may be used. As an example of a commercial item, the adhesive sheet (PD-S1 etc.) by Panac Co., Ltd., the MHM series adhesive sheet of Nichiei Kako Co., Ltd., etc. are mentioned.
The thickness of the OCA tape may be 1.0 μm to 50 μm, and preferably 2.0 μm to 30 μm.
<Laminated glass>
The real image display member of the present invention can be used for the production of laminated glass. The real image display member of the present invention can be used for the production of an intermediate layer of laminated glass. The real image display member of the present invention can be a material for providing a function as a half mirror film in an intermediate layer of laminated glass. The real image display member of the present invention is a production intermediate in the production of laminated glass including a retardation layer in the intermediate layer.

  Laminated glass has a configuration in which two glass plates are bonded via an intermediate layer. The laminated glass manufactured 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 in FIG. The first glass plate 31, the first resin film 11, the real image display member 13 including a cholesteric liquid crystal structure, the second resin film 12, and the second glass plate 32 are arranged in this order. The intermediate layer 21 includes 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 this specification, the windshield glass means a window glass for vehicles such as cars, trains, airplanes, ships, play equipment and the like. The windshield glass is preferably a windshield in the direction of travel of the vehicle. The windshield glass is preferably a vehicle windshield.

  The laminated glass should just be planar. The laminated glass may be shaped for incorporation into an applied vehicle, and may have a curved surface, for example. In a laminated glass formed for a vehicle to be applied, a direction that is upward (vertically upward) and a surface that is an observer side can be specified during normal use. In addition, in this specification, when it says that it is vertically above about a laminated glass or a projection image display site | part, it means the direction which becomes vertically above at the time of use which can be specified as mentioned above.

<Glass plate>
In this specification, in the laminated glass, the glass plate which becomes the outside is referred to as a first glass plate, and the glass plate on the indoor side is referred to as a 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 is called the second glass plate.
In the present specification, the term “glass plate” means both the first glass plate and the second glass plate.

  As a glass plate, the glass plate generally used for the laminated glass for windshield glass can be utilized. Although there is no restriction | limiting in particular about the thickness of a glass plate, What is necessary is just about 0.5 mm-5.0 mm, 1.0 mm-3.0 mm are preferable, and 1.6 mm-2.3 mm are more preferable. The thicknesses 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 glass plate may be subjected to surface treatment for imparting water repellency, hydrophilicity, or antifogging property to the surface thereof.
The glass plate is preferably cut into the shape of windshield glass. Moreover, 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 this specification, when the laminated glass is used as a windshield glass, the resin film on the outside is referred to as a first resin film, and the resin film on the indoor side is referred to as a second resin film. In other words, a resin film located farther from the driver (observer) side is referred to as a first resin film, and a resin film located closer to the driver is referred to as a second resin film.
The first resin film and the second resin film may be the same or different in material, thickness, and the like. The materials are preferably the same, and more preferably the materials and thickness 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 only needs to have the same shape and area as the first glass plate. For example, in the laminated glass manufacturing process, the resin film unwound from the roll form is sandwiched between the first glass plate and the second glass plate, and then trimmed into the shape of the first glass plate. Good.

As the resin film, a known resin film may be used as a sheet used for the intermediate layer of the laminated glass. The resin film contains a resin as a main component. The main component refers to a component that occupies a ratio of 50% by mass or more of the interlayer 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 that have been used for intermediate layers of laminated glass. For example, polyvinyl acetal, polyvinyl chloride, saturated polyester, polyurethane, ethylene-vinyl acetate copolymer, ethylene -Ethyl acrylate copolymer etc. are mentioned. Among these, polyvinyl acetal is preferable from the viewpoints of transparency, strength, light resistance, and the like.

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

  Of 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 preferable lower limit of the degree of acetalization of the polyvinyl butyral is 40%, the preferable upper limit is 85%, the more preferable lower limit is 60%, and the more preferable 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.
Moreover, the preferable minimum of the polymerization degree of the said polyvinyl alcohol is 200, and a preferable upper limit is 3000. When the polymerization degree of polyvinyl alcohol is 200 or more, the penetration resistance of the obtained laminated glass is difficult 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 increase too much. Good workability. A more preferred lower limit is 500, and a more preferred upper limit is 2000.

The resin is also preferably plasticized by the addition of a plasticizer. For example, as the plasticizer, phosphate ester, carboxylic acid ester, sugar ester, polycondensation ester, or the like is used.
The addition amount of the plasticizer 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 a plasticizer, the thermoplastic resin can be sufficiently plasticized. Moreover, the intensity | strength of a resin layer can fully be maintained by the addition amount of a plasticizer being 80 mass parts or less.

  In addition to the plasticizer, the resin film or the composition for forming the resin film is an infrared shielding fine particle, an adhesion adjusting agent, a coupling agent, a surfactant, an antioxidant, a heat stabilizer, a light stabilizer, One type or two or more types of various additives such as an ultraviolet absorber, a fluorescent agent, a dehydrating agent, an antifoaming agent, an antistatic agent, and a flame retardant may be included.

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

<Method for Manufacturing Real Image Display Member>
The real image display member can be produced by providing a light reflecting layer including a cholesteric liquid crystal layer on the surface of a laminate obtained by producing a retardation layer and an alignment layer on a support or a peelable support. .
As a manufacturing method, a method of crimping both over a certain temperature, a certain pressure, and a certain time, and a method of crimping with a roll-to-roll (laminate at a certain pressure as an upper roll at a predetermined temperature and a lower roll at a predetermined temperature). Any method may be used.
The heating and pressurization at the time of 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. The following may be done.

<Method for producing interlayer film and laminated glass>
The intermediate film 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.

  Laminated glass can be manufactured using a known laminated glass manufacturing method. For example, the intermediate film sheet obtained as described above can be further produced by subjecting a laminate obtained by further sandwiching between two glass plates to preliminary pressure bonding and main pressure bonding. Alternatively, the second resin film and the second glass plate are provided in this order on one surface of the real image display member, and the first resin film and the first glass plate are provided on the opposite surface of the real image display member. It can manufacture with the manufacturing method including providing. When providing the second resin film and the second glass plate, and the first glass plate, the second glass plate, the second resin film, the real image display member, the first resin film, and the first glass film A glass plate is laminated in this order, and the laminate can be manufactured by performing pre-compression and main-compression. In addition, each may be sequentially pressure-bonded, or one having a first resin film provided on a first glass plate in advance may be used.

  Pre-compression bonding is a process performed for deaeration between layers in the production of laminated glass. The pre-compression is performed, for example, by putting the laminated body in a rubber bag connected to an exhaust system. The pressure at this time is preferably 100 kPa or less, and more preferably 1 to 36 kPa. The pre-bonding can be performed by holding at a temperature of 70 ° C. to 130 ° C. for 10 minutes to 90 minutes.

  By setting the holding temperature to 70 ° C. or higher, the preliminary pressure bonding can be made sufficient. Moreover, since the thermal contraction of the functional layer can be prevented from proceeding excessively by setting the holding temperature to 130 ° C. or lower, the occurrence of cracks in the functional layer can be suppressed. The holding temperature is preferably 80 ° C. or higher, and more preferably 90 ° C. or higher. This is for performing deaeration more reliably. Further, the holding temperature is preferably 120 ° C. or lower, and more preferably 110 ° C. or lower.

  When the holding time is 10 minutes or longer, the preliminary pressure bonding can be sufficiently performed. On the other hand, if the holding time is 90 minutes or less, the productivity is good and the thermal contraction of the functional layer material can be prevented from proceeding excessively, so that the occurrence of cracks in the functional layer can be suppressed. The holding time is preferably 20 minutes or longer and 60 minutes or shorter from the viewpoint of more effectively and efficiently performing preliminary pressure bonding.

  The main pressure bonding is performed in order to sufficiently bond each layer with a resin film. For example, a pre-pressure bonded body obtained by pre-pressure bonding is put in an autoclave, and the temperature is 120 ° C. or higher and 150 ° C. or lower and the pressure is 0.98 MPa. This can be performed at a pressure of 1.47 MPa or less. More preferably, the temperature is 130 ° C. to 140 ° C. and the pressure is 1.1 MPa to 1.4 MPa. And it is preferable that it is 30 minutes or more and 90 minutes or less, and, as for the time (holding time) hold | maintained at the said temperature and pressure, it is more preferable that they are 45 minutes or more and 75 minutes or less.

  By performing the main pressure bonding under the above conditions of the holding temperature, holding pressure, or holding time, it is possible to suppress the occurrence of cracks in the functional layer, and the productivity is excellent.

<< Real image display system >>
The real image display system includes the real image display member of the present invention and a 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 this specification, the “projector” is “an apparatus that projects light or an image”, and includes an “apparatus that projects a drawn image”. In the real image display system, the projector may be arranged so as to be incident on the real image display member bonded to the glass plate or the real image display member in the laminated glass at an oblique incident angle as described above.
In the real image display system, the projector preferably 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, laser luminance modulation means, or light deflection means for drawing. In this specification, the drawing device means a device that includes a light source and further includes a light modulator, a laser luminance modulation unit, a light deflection unit for drawing, or the like according to a drawing method.

(light source)
The light source is not particularly limited, and LEDs (including light emitting diodes and organic light emitting diodes (OLED)), discharge tubes, laser light sources, and the like can be used. Of these, LEDs and laser light sources are preferred. This is because it is suitable for a light source of 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 application, and is not particularly limited.
Examples of the drawing method include a fluorescent display tube, an LCD (Liquid Crystal Display) method using a liquid crystal, an LCOS (Liquid Crystal on Silicon) method, a DLP (registered trademark) (Digital Light Processing) method, and a scanning method using a laser. Etc. The drawing method may be a method using a fluorescent display tube integrated with a light source.

In the LCD method and the LCOS method, light of each color is modulated and combined by an optical modulator, and light is emitted from a projection lens.
The DLP system is a display system using DMD (Digital Micromirror Device), and is drawn by arranging micromirrors corresponding to the number of pixels, and light is emitted from a projection lens.
The scanning method is a method in which a light beam is scanned on a screen and an image is contrasted using an afterimage of an eye. For example, the descriptions in JP-A-7-270711 and JP-A-2013-228664 can be referred to. In the scanning method using laser, laser light of each color (for example, red light, green light, and blue light) whose luminance is modulated is bundled into one light beam by a multiplexing optical system or a condenser lens, and the light beam is light. It only needs to be scanned by the deflecting means and drawn on an intermediate image screen described later.

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

  The outgoing light 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. When the output light is a linearly polarized light drawing device and the output light contains light of a plurality of wavelengths (colors), the polarization directions (transmission axis directions) of the plurality of light polarizations are the same or orthogonal to each other It is preferable. It is known that there are commercially available drawing devices whose polarization directions are not uniform in the wavelength range of the emitted red, green, and blue light (see Japanese Patent Application Laid-Open No. 2000-212449). Specifically, an example in which the polarization direction of green light is orthogonal to the polarization direction of red light and the polarization direction of blue light is known.

[Projection light (incident light)]
Incident light is preferably incident at an oblique incident angle of 45 ° to 70 ° with respect to the normal of the projected image display region. When the projection light is reflected on the front surface or the back surface of the glass, it is diffusely reflected again by the real image display member, thereby causing image blur due to multiple images. This is because it is useful for this image blur reduction method to make projection light (p-polarized light) incident on the glass surface at a Brewster angle so that the reflected light from the glass surface approaches zero. (For example, refer to Japanese translations of PCT publication No. 2006-512622). Further, in a mode in which the real image display member having the retardation layer A is bonded to 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 about 1 is about 56 °. When p-polarized light is incident from the glass side in the above angle range, circularly polarized light selectively reflected by the layer containing the cholesteric liquid crystal structure is converted into p-polarized light by the retardation layer A. Therefore, image display with reduced image blur is possible. The angle is preferably 50 ° to 65 °.

  In the aspect in which the real image display member of the present invention has the retardation layer A, incident light is incident on the layer including the cholesteric liquid crystal structure from the retardation layer A side, and the cholesteric liquid crystal structure passes through the retardation layer A. May be incident on a layer containing. That is, the retardation layer A may be disposed on the incident side of the projection 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 according to the direction of the observer. For example, the incident light may be incident at an oblique incident angle as described above from the downward direction during use.

  As described above, it is preferable that the projection light at the time of projection image display in the real image display system is p-polarized light that vibrates in a direction parallel to the incident surface. When the output light of the projector is not linearly polarized light, it may be p-polarized by using a linearly polarizing film arranged on the output light side of the projector, or it may be p-polarized in the optical path from the projector to the laminated glass Good. As described above, for projectors whose polarization directions in the red, green, and blue light wavelength ranges are not uniform, the polarization direction is adjusted in a wavelength-selective manner, and p-polarized light is used in all color wavelength ranges. It is preferable to make it enter.

  The real image display member of the present invention is particularly useful for a transparent screen or a head-up display system that uses a laser, LED, OLED or the like whose light emission wavelength is not continuous in the visible light region in combination with a projector using a light source. This is because the central wavelength of 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 and ratios of substances, operations, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the present invention is not limited to the following examples.

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

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

<Preparation of orientation layer Y1>
On the surface of Cosmo Shine A-4100 (PET, thickness 75 μm) manufactured by Toyobo Co., Ltd. as the peelable support, the orientation layer coating solution Y1 having the following composition is applied with a # 3.6 wire bar coater. Applied. Then, it dried at 45 degreeC for 60 second, and irradiated the ultraviolet ray of 500 mJ / cm < ² > with the ultraviolet irradiation device at 25 degreeC, and produced alignment layer Y1 with a peeling support body.

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

Fluorine horizontal alignment agent F1

<Preparation of Cholesteric Liquid Crystal Layers B1, G1, R1, IR1, IR2>
(Cholesteric liquid crystal layer coating solutions B1, G1, R1, IR1, IR2)
The following components were mixed to prepare a coating solution 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 (BASF) 1.5 parts by mass Methyl ethyl ketone Listed in Table 2

Mixture of compound 1 (value is% by mass)

Fluorine horizontal alignment agent F2

Cholesteric liquid crystal coating liquids B1, G1, R1, IR1, and IR2 were prepared by adjusting the formulation amount of the chiral agent LC-756 having the above coating liquid composition and the amount of methyl ethyl ketone. Using each coating solution, a single layer of cholesteric liquid crystal layer was prepared on a peelable support in the same manner as in the preparation of the following functional layers, and the reflection characteristics were confirmed. The central reflection wavelength was as shown in Table 1 below.
Here, the central reflection wavelength is a cholesteric liquid crystal using a spectrophotometer (manufactured by JASCO Corporation, V-550) and a large integrating sphere device (manufactured by JASCO Corporation, ILV-471). It is a value calculated based on the integrated reflectance measured without using an optical trap so that light enters from the layer side. Specifically, it is a mountain shape with the wavelength on the horizontal axis (upward convex) The average reflectance (arithmetic average) of the maximum and minimum integral reflectances in the integral reflectance spectrum is obtained, and the wavelength value on the short wavelength side of the two wavelengths at the two intersections of the waveform and the average reflectance is λA ( nm), the wavelength value on the long wave side is λB (nm), and is a value calculated by the following formula.
Central reflection wavelength = (λA + λB) / 2

The coating liquid B1 for cholesteric liquid crystal layer prepared above was applied to the surface of the alignment layer Y1 with a release support with a # 2.6 wire bar coater. Then, it dried at 95 degreeC for 60 second, and the cholesteric liquid crystal layer B1 which reflects the light of central wavelength 435nm was produced by irradiating an ultraviolet-ray of 500 mJ / cm < ² > with an ultraviolet irradiation device at 25 degreeC. Next, the cholesteric liquid crystal layer coating liquid G1 prepared above was applied to the surface of the cholesteric liquid crystal layer B1 with a # 2.0 wire bar coater. Then, it dried at 95 degreeC for 60 second, and the cholesteric liquid crystal layer G1 which reflects the light of central wavelength 545nm was laminated | stacked by irradiating an ultraviolet ray of 500 mJ / cm < ² > with an ultraviolet irradiation device at 25 degreeC. Next, the cholesteric liquid crystal layer coating liquid R1 prepared above was applied to the surface of the cholesteric liquid crystal layer G1 with a # 2.0 wire bar coater. Then, it dried at 95 degreeC for 60 second, and the cholesteric liquid crystal layer R1 which reflects the light of central wavelength 650nm was laminated | stacked by irradiating an ultraviolet ray of 500 mJ / cm < ² > with an ultraviolet irradiation device at 25 degreeC. Next, the cholesteric liquid crystal layer coating liquid IR1 prepared above was applied to the surface of the cholesteric liquid crystal layer R1 produced with a # 2.6 wire bar coater. Then, it dried at 95 degreeC for 60 second, and the cholesteric liquid crystal layer IR1 which reflects the light of central wavelength 840nm was laminated | stacked by irradiating an ultraviolet ray of 500 mJ / cm < ² > with an ultraviolet irradiation device at 25 degreeC. Furthermore, display member RS-2 was produced by peeling the peeling support.

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

<Production of Retardation Layers RE-2 to RE-7>
(Phase difference layer forming coating solution RE-2)
The following components were mixed to prepare a retardation layer forming coating solution RE-2 having the following composition.
-Mixture of Compound 1 100 parts by mass-0.01 part by weight of fluorine-based horizontal alignment agent F1-0.05 part by weight of fluorine-based horizontal alignment agent F2-IRGACURE OXE01 (manufactured by BASF)
1.0 part by mass / Methyl ethyl ketone The amount that the solute concentration is 25% by mass

Rubbing treatment was applied to the surface of Toyobo Co., Ltd. Cosmo Shine A-4100 (PET, thickness 75 μm) as an exfoliating support that had been rotated 60 ° counterclockwise from the TD direction. The retardation layer forming coating solution RE-2 was applied using a wire bar. Thereafter, the substrate is dried at 50 ° C. for 60 seconds, and irradiated with an ultraviolet ray of 500 mJ / cm ² at 50 ° C. with an ultraviolet irradiation device 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 the peeling support, the same method except that the rubbing angle was adjusted while changing the bar number to adjust the film thickness so as to have the configuration shown in Table 3. Then, retardation layers RE-3 to 7 with a release support were produced. The results of measuring the front retardation Re (550) of the retardation layer at a wavelength of 550 nm using AxoScan (manufactured by Axometrics) are shown in Table 2 below.

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

[Examples 3 to 13]
<Production of display members RS-4 to 14>
In the production of the display member RS-3, the display member RS-4 to the display member RS-4 to the same method except that the phase difference layer with a peeling support, the alignment film, and the cholesteric liquid crystal layer are changed to the combinations shown in Table 3 below. 14 was produced. Of the display members RS-4 to RS-14, in the aspect using the phase difference layers RE-2 to RE-7 with the peelable support, the display member is the one that is finally peeled off. In the embodiment using the retardation layers RE-8 and RE-9, a retardation layer was formed on the alignment film Y2 to produce a display member.

<Preparation of Cholesteric Liquid Crystal Layers G2, G4-7>
A cholesteric liquid crystal layer G2 was produced in the same manner as in the production of the cholesteric liquid crystal layer G1, except that the bar number was changed to # 2.8. Similarly, cholesteric liquid crystal layers G4 to G7 were produced in the same manner except that the bar number was changed.

<Preparation of cholesteric liquid crystal layers G3 and IR3>
In coating liquid G1 and 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) is added to 100 parts by mass of the mixture of compound 1. The coating liquid G3 and IR3 were adjusted.
A cholesteric liquid crystal layer G3 was produced in the same manner as in the production of the cholesteric liquid crystal layer G2, except that the coating solution was changed to G3.
A cholesteric liquid crystal layer IR3 was produced in the same manner as in the production of the cholesteric liquid crystal layer IR2, except that the coating solution was changed to IR3.

<Preparation of cholesteric liquid crystal layers IR4-7>
Cholesteric liquid crystal layers IR4 to IR7 were produced in the same manner as in the production of the cholesteric liquid crystal layer IR2, except that the bar number was changed.

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

Fluorine horizontal alignment agent F3

  Cholesteric liquid crystal coating liquids B2, G8, and R2 were prepared by adjusting the prescription amount, methyl ethyl ketone amount, and cyclohexanone amount of the fluorine-based horizontal alignment agent F3 and chiral agent LC-756 having the above coating liquid composition. Using each coating solution, a single layer of cholesteric liquid crystal layer was prepared on a peelable support in the same manner as in the preparation of the following functional layers, and the reflection characteristics were confirmed. It was a polarizing reflection layer, and the central reflection wavelength was as shown in Table 3 below.

The coating liquid B1 for cholesteric liquid crystal layer prepared above was applied to the surface of the alignment layer Y1 with a release support with a # 3 wire bar coater. Then, it dried at 45 degreeC for 60 second, and the cholesteric liquid crystal layer B2 which reflects the light of central wavelength 482nm was produced by irradiating an ultraviolet ray of 500 mJ / cm < ² > with an ultraviolet irradiation device at 40 degreeC. Next, the cholesteric liquid crystal layer coating liquid G8 prepared above was applied to the surface of the cholesteric liquid crystal layer B2 with a # 3 wire bar coater. Then, it dried at 45 degreeC for 60 second, and the cholesteric liquid crystal layer G1 which reflects the light of central wavelength 606nm was laminated | stacked by irradiating an ultraviolet ray of 500mJ / cm < ² > with an ultraviolet irradiation device at 40 degreeC. Next, the cholesteric liquid crystal layer coating liquid R1 prepared above was applied to the surface of the cholesteric liquid crystal layer G8 with a # 3 wire bar coater. Then, it dried at 45 degreeC for 60 second, and the cholesteric liquid crystal layer R1 which reflects the light of central wavelength 667nm was laminated | stacked by irradiating an ultraviolet ray of 500 mJ / cm < ² > with an ultraviolet irradiation device at 40 degreeC. Furthermore, display member RS-14 was produced by peeling the peeling support.

<Production 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 an air layer cellulose ester solution.

Composition of cellulose ester solution for air layer: 100 parts by mass of cellulose ester (acetyl substitution degree: 2.86) 3 parts by mass of sugar ester compound of formula (RI) 1 part by mass of sugar ester compound of formula (R-II) -2.4 parts by weight of the following UV absorber-Silica particle dispersion (average particle size 16 nm) "AEROSIL R972",
Made by Nippon Aerosil Co., Ltd. 0.026 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 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: 100 parts by mass of cellulose ester (acetyl substitution degree 2.86) 3 parts by mass of sugar ester compound of formula (RI) 1 part by mass of sugar ester compound of formula (R-II) UV absorber 2.4 parts by mass Silica particle dispersion (average particle size 16 nm) “AEROSIL R972”,
Nippon Aerosil 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 the 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-UV absorber 2.4 parts by weight-Methylene chloride 266 parts by mass-Methanol 58 parts by mass-Butanol 2.6 parts by mass

(Filming by co-casting)
As a casting die, an apparatus equipped with a feed block adjusted for co-casting so that a film having a three-layer structure can be formed was used. The air layer cellulose ester solution, the core layer cellulose ester solution, and the drum layer cellulose ester solution were co-cast from a casting port onto a drum cooled to -7 ° C. At this time, the flow rate of each dope was adjusted so that the thickness ratio was air layer / core layer / drum layer = 7/90/3.
It casted on the mirror surface stainless steel support body which is a drum of diameter 3m. A dry air of 34 ° C. was applied on the drum at 270 m ³ / min.
The cellulose ester film cast and rotated 50 cm before the end point of the casting part was peeled off from the drum, and then both ends were clipped with a pin tenter. During peeling, 5% stretching was performed in the transport direction (longitudinal direction).

The cellulose ester web held by the pin tenter was conveyed to the drying zone. In the first drying, a drying air of 45 ° C. was blown and then dried at 110 ° C. for 5 minutes. At this time, the cellulose ester web was conveyed while stretching in the width direction at a magnification of 10%.
After the web was detached from the pin tenter, the portion held by the pin tenter was continuously cut out, and unevenness with a width of 15 mm and a height of 10 μm was made at both ends in the width direction of the web. 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. Furthermore, the width direction edge part was continuously cut out so that a web might become a desired width | variety, and the 41-micrometer-thick cellulose ester film was produced. This film is designated as transparent support A.

<Preparation of alignment film Y2>
On the surface of the transparent support A, an alignment layer coating solution Y2 having the following composition was applied with a # 16 wire bar coater. Thereafter, the film was dried at 60 ° C. for 60 seconds and further at 90 ° C. for 150 seconds. Subsequently, the transparent support body with the orientation layer Y2 was produced by performing the rubbing process by rotating the coated surface side with a rubbing roll in a direction parallel to the conveying direction at a clearance of 1.0 mm and 1000 rpm. The alignment film Y2 and the transparent support were in strong contact and could not be peeled off.

(Alignment layer coating solution Y2)
-10 parts by weight of the following modified polyvinyl alcohol-370 parts by weight of water-120 parts by weight of methanol-0.5 parts by weight of glutaraldehyde (crosslinking agent)

  In the production of the retardation layer RE-3 with a release support, a retardation layer was formed on the alignment layer Y2 in the same manner except that a transparent support with an alignment layer Y2 was used instead of the release support A-4100. A retardation layer RE-8 in which was formed. 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 thickness of the retardation layer RE-8 was adjusted by changing the bar number and the rubbing angle was adjusted. -9 was produced. When the front retardation Re (550) of the retardation layer at a wavelength of 550 nm was measured with AxoScan (manufactured by Axometrics) using AxoScan (manufactured by Axometrics), Re (550) was 370 nm.

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

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

<Measurement of integral reflectance>
A large integrating sphere device (manufactured by JASCO Corporation, ILV-471) is connected to a spectrophotometer (manufactured by JASCO Corporation, V-550) so that light enters from the phase difference A side described in Table 4. The integral reflection spectrum of the display member was measured by using the one attached with a light trap without using an optical trap so as to include specular reflection light. 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 is short-wave shifted by increasing the detection angle. The reflection band measured at a wavelength of 620 to 680 nm at normal incidence corresponds to a reflection band of around 550 nm when incident from a polar angle of 60 °.

<Measurement of reflectance>
The incident angle (polar angle, azimuth angle), light receiving angle (polar angle, azimuth angle), and measurement wavelength region are set appropriately so that light enters from the phase difference A side described in Table 4, and the three-dimensional variable angle Using a spectral colorimetry system (GCMS-3B, manufactured by Murakami Color Research Laboratory Co., Ltd.), the reflectances R [-60,40] (550) and R [-60,30] (550) of the display member Was measured. Here, R [−60, θ] (550) is the polar angle θ at an azimuth angle that is 180 ° shifted from the azimuth angle of the incident light with respect to the incident light having a polar angle of −60 ° to the decorative sheet. It is the reflectance at a wavelength of 550 nm, measured by the light receiving angle. Further, when the front reflectivity is high and the reflected light of R [−60, 30] (550) is 0%, it is described in Table 4 as “Cannot be calculated”.

<Measurement of average value of peak-to-peak distance of corrugated structure>
When the cross section of the cholesteric liquid crystal layer of the display member is observed using a scanning electron microscope (SEM), a stripe pattern of a bright part and a dark part is observed. From the striped wavy structure, the distance in the planar direction of the cholesteric liquid crystal layer was measured for two peaks or valleys at an inclination angle of 0 ° located at the closest positions. A value obtained by arithmetically averaging the cholesteric liquid crystal layer with a length of 100 μm in the longitudinal direction of the cross section and the total film thickness was defined as an average value of the peak-to-peak distance of the wavy structure.

<Evaluation with glass paste>
A glass plate having a length of 50 mm × width of 50 mm and a thickness of 2 mm was bonded to the phase difference A side of the display member using an acrylic adhesive SK-2057 (manufactured by Soken Chemical Co., Ltd.). A projector (Seiko Epson Co., Ltd., EB-G6250W) was placed on the glass side, and the visibility of the image was evaluated from the following viewpoint in a state where the glass was in focus. Note that the evaluation was made for two types of light emitted from the projector: non-polarized light and P-polarized light.
A: A real image with sufficient brightness and no blur is visually recognized.
B: Bright but slightly blurred real image is visible.
C: Although a real image is visually recognized, it is dark.
D: A real image cannot be visually recognized.

<Evaluation with laminated glass>
A 0.38 mm thick PVB (polyvinyl butyral) film made by Sekisui Chemical Co., Ltd., cut to the same size on a glass plate having a length of 300 mm × width of 300 mm and a thickness of 2 mm, is placed, and the display member is placed on the phase difference A side. Was placed on the bottom surface, and a glass plate having a length of 300 mm × width of 300 mm and a thickness of 2 mm was placed thereon. After maintaining this at 90 ° C. and 10 kPa (0.1 atm) for 1 hour, the autoclave (manufactured by Kurihara Seisakusho) is heated at 115 ° C. and 1.3 Mpa (13 atm) for 20 minutes to remove bubbles, and combined. Glass was obtained.
A projector (Seiko Epson Co., Ltd., EB-G6250W) is disposed on the phase difference A side of the laminated glass produced using the display members RS-1 to 14, and the light emitted from the projector is converted to P-polarized light. The visibility of the image was evaluated from the following viewpoints with the glass in focus.
A: A real image with sufficient brightness and no blur is visually recognized.
B: Bright but slightly blurred real image is visible.
C: Although a real image is visually recognized, it is dark.
D: A real image cannot be visually recognized.

<Evaluation of visible light transmittance>
The transmittance of the produced laminated glass was measured using a luminance meter BM-5A (manufactured by Topcon Corporation). Evaluation was made from the following viewpoints based on a visible light transmittance of 70% or more required as a windshield glass.
A: 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 because R [−60,30] (550) is 0%. The average value of the peak-to-peak distance of the wavy structure is indicated as “-” because it does not have a wavy structure.

DESCRIPTION OF SYMBOLS 1 Light reflection layer 2 Alignment layer 3 Phase difference layer A
4 Support 5 Retardation 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 51 at the time of measurement Reflected light 52 with a polar angle of 40 degrees at the time of measurement Reflected light with polar angle of 30 degrees

Claims (14)

Having 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,
At least one of the light reflecting layers is formed of a cholesteric liquid crystal layer;
The spiral sense of all cholesteric liquid crystal layers is the same,
A real image display member satisfying the following formula (1).
R [−60, 40] (550) / R [−60, 30] (550) ≧ 1.5 Formula (1)
Here, R [−60, 40] (550) is polar angle 40 at an azimuth angle that is 180 ° shifted from the azimuth angle of the incident light with respect to incident light having a polar angle of −60 ° to the real image display member. R [−60, 30] (550) represents the reflectance at a wavelength of 550 nm measured at a light receiving angle of °, and R [−60, 30] (550) represents the incident light with respect to the incident light having a polar angle of −60 ° to the real image display member. The reflectance at a wavelength of 550 nm, which is measured at a light receiving angle of 30 ° polar angle at an azimuth angle that is 180 ° shifted from the azimuth angle of γ is shown.   The real image display member according to claim 1, 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 stripe pattern of a bright part and a dark part observed by a scanning electron microscope in a cross section, the stripe pattern has a wavy structure, and an average of distances between peaks of the wavy structure The real image display member according to claim 1, wherein the value is 0.5 μm to 50 μm.
Here, the wavy structure means that there is 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 a continuous line of a bright part or a dark part in a striped pattern, and sandwiches the region M. This indicates that two peaks or valleys with an inclination angle of 0 ° at the closest positions are specified.
Further, the peak-to-peak distance of the wavy structure is the distance between the cholesteric liquid crystal layers in the plane direction of the two peaks or valleys having an inclination angle of 0 ° that are closest to each other with the region M interposed therebetween. Represents a value obtained by arithmetic averaging of 100 μm in the long axis direction of the cross section and the total film thickness.   The member for real image display according to any one of claims 1 to 3, wherein the maximum reflectance of the integrated reflectance at a wavelength of 620 to 680 nm is 15 to 28%.   The real image display member according to claim 2, further comprising a retardation layer B on a surface opposite to the surface where the retardation layer A of the light reflection layer is provided.   The real image display member according to claim 5, wherein a narrow angle formed by a slow axis of the retardation layer A and a slow axis of the phase difference B is 40 ° to 85 °.   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 is any one of claims 1 to 6. A real image display member comprising the real image display member according to Item.   The real image display member according to claim 7, which is a windshield glass.   The real image display member according to claim 7, wherein the intermediate layer is a resin film.   The real image display member according to claim 9, wherein the resin film contains polyvinyl butyral.   The member for real image display as described in any one of Claims 1-10 used as a vehicle-mounted display system.   A projection image display system comprising the real image display member according to claim 1 and a projector, wherein the incident light of the projector is p-polarized light that vibrates in a direction parallel to the incident surface.   The projection image display system according to claim 12, wherein the incident light is incident at an angle of 40 ° to 70 ° with respect to a normal line of the projection image display member.   The projection image display system according to claim 12 or 13, wherein the incident light is incident from below when the projection image display member is used.