JPH10104565A - Reflective guest-host liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the refractive index anisotropy of a quarter-wave plate layer incorporated in a reflection type guest-host liquid crystal display device and to stabilize optical characteristics. SOLUTION: The reflection type guest-host liquid crystal display device is assembled using a substrate 1 arranged on the incident side and a substrate 2 joined to the substrate 1 via a predetermined gap and arranged on the reflection side. A guest-host liquid crystal layer 3, a light reflecting layer 5, and a quarter-wave plate layer 4 are interposed in the gap between the substrates 1 and 2. The guest-host liquid crystal layer 3 has a dichroic dye 7 added thereto,
It is located on the substrate 1 side. The quarter-wave plate layer 4 is located on the substrate 2 side and is interposed between the guest-host liquid crystal layer 3 and the light reflection layer 5. A counter electrode 8 and a pixel electrode 9 for applying a voltage to the guest host liquid crystal layer 3 are formed on the substrates 1 and 2, respectively. The quarter-wave plate layer 4 is made of a uniaxially oriented side chain type liquid crystalline polymer, and has at least methoxyphenyl benzoate as a pendant entering the side chain, and has improved optical characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reflection type guest-host liquid crystal display device. More specifically, the present invention relates to an integrated polarization conversion guest-host liquid crystal display device having a built-in quarter-wave plate layer and a light reflection layer to improve the use efficiency of incident light. More specifically, the present invention relates to a composition of a liquid crystalline polymer constituting a quarter-wave plate layer.

[0002]

2. Description of the Related Art An integrated polarization conversion guest-host liquid crystal display device is disclosed in, for example, JP-A-6-222351, and FIG. 7 schematically shows the structure thereof. As shown, the reflective liquid crystal display device 101 basically includes a pair of upper and lower substrates 102 and 103, a guest host liquid crystal layer 10
4, a dichroic dye 105, transparent electrodes 106 and 110, alignment films 107 and 111, a light reflecting layer 108, a quarter-wave plate layer 109, and the like. The pair of upper and lower substrates 102 and 103 are made of an insulating material such as glass, quartz, plastic, or the like, and at least the upper substrate 102 has translucency. A guest-host liquid crystal layer 104 containing a dichroic dye 105 is interposed between the substrates 102 and 103. This liquid crystal layer 104 is composed of nematic liquid crystal molecules 104.
a. Dichroic dye 10 contained therein
5 is a so-called p-type dye having a transition dipole moment substantially parallel to the long axis of the molecule. Although not shown, a switching element is formed on the inner surface 102a of the upper substrate 102. The transparent electrode 106 is a pixel electrode patterned in a matrix and is driven by a corresponding switching element. On the inner surface 102a of the substrate 102 on which the switching elements and the pixel electrodes 106 are formed, an alignment film 107 made of a polyimide resin or the like is further formed.
The surface of the alignment film 107 is rubbed, and the liquid crystal molecules 104a are horizontally aligned. On the other hand, on the inner surface 103a of the lower substrate 103, a light reflection layer 108 made of aluminum or the like and a quarter-wave plate layer 109 are formed in this order. The quarter-wave plate layer 109 is made of, for example, a uniaxially oriented liquid crystalline polymer. Further, a transparent electrode 110 and an alignment film 111 are formed on the surface of the quarter-wave plate layer 109 in this order. Like the facing alignment film 107, the alignment film 111 is made of, for example, a polyimide resin, and its surface is subjected to a rubbing process.

[0003] Next, the operation when black and white display is performed using the reflection type liquid crystal display device 101 will be briefly described. In a state where no voltage is applied, the liquid crystal molecules 104a are aligned with the alignment films 107 and 11.
1 are oriented horizontally along the rubbing direction of the dichroic dye 1
05 is similarly oriented. When light incident from the upper substrate 102 enters the guest-host liquid crystal layer 104, a component of the incident light having a vibration plane parallel to the major axis direction of the molecules of the dichroic dye 105 is absorbed by the dichroic dye 105. Is done.
The component of incident light having a vibration plane perpendicular to the major axis direction of the molecules of the dichroic dye 105 is the guest host liquid crystal layer 104.
, And is converted into circularly polarized light by the quarter-wave plate layer 109 formed on the surface 103 a of the lower substrate 103.
08 and reflected. At this time, the polarization direction of the reflected light is reversed, and the reflected light again passes through the quarter-wave plate layer 109 and becomes light having a vibration plane parallel to the major axis direction of the molecules of the dichroic dye 105. Since this light is absorbed by the dichroic dye 105, a substantially complete black display is obtained. On the other hand, when a voltage is applied, the liquid crystal molecules 104a are vertically aligned along the direction of the electric field,
The dichroic dye 105 is similarly oriented. Upper substrate 102
Light incident from the side passes through the guest-host liquid crystal layer 104 without being absorbed by the dichroic dye 105, and is reflected by the light reflection layer 108 without being polarized by the quarter-wave plate layer 109.
The reflected light passes through the quarter-wave plate layer 109 again,
The light is emitted without being absorbed by the guest host liquid crystal layer 104. Therefore, white display is obtained.

[0004]

In the conventional structure shown in FIG. 7, a uniaxially oriented liquid crystalline polymer is used as the quarter-wave plate layer 109. When a liquid crystalline polymer is uniaxially oriented, a refractive index anisotropy appears. The measure of the refractive index anisotropy is indicated by the difference (Δn) in the refractive index along the optical axes orthogonal to each other. The product of the thickness d and Δn of the liquid crystalline polymer is called retardation. By setting this value to be λ / 4 (where λ is the wavelength of the incident light), a quarter-wave plate layer is formed. As a result. However, the conventional liquid crystalline polymer does not have a material having excellent optical properties as a refractive index anisotropic body, and has been a problem to be solved.

[0005]

The following means have been taken in order to solve the above-mentioned problems of the prior art. That is, the reflection type guest-host liquid crystal display device according to the present invention has, as a basic configuration, a first substrate disposed on the incident side, and joined to the first substrate via a predetermined gap and disposed on the reflection side. A second substrate, a guest-host liquid crystal layer to which the dichroic dye is added and located on the first substrate side in the gap, a light-reflecting layer located on the second substrate side in the gap, and the guest-host liquid crystal A quarter-wave plate layer interposed between the layer and the light reflection layer, and electrodes formed on the first substrate side and the second substrate side, respectively, for applying a voltage to the guest host liquid crystal layer. . As a characteristic feature, the quarter-wave plate layer is made of a uniaxially oriented side chain type liquid crystalline polymer, and has at least methoxyphenyl benzoate as a pendant entering the side chain. In one embodiment, an alignment film is formed on each of the interfaces of the first substrate and the second substrate that are in contact with the guest-host liquid crystal layer, and the guest-host liquid crystal liquid crystal layer is vertically aligned and formed on the second substrate side. The alignment film thus formed is a silane coupling film formed in contact with the quarter-wave plate layer. Alternatively, as the alignment film formed on the second substrate side, a polyimide film formed on the quarter-wave plate layer via a protective film may be used. In another aspect of the present invention, an alignment film is formed on each of the interfaces of the first substrate and the second substrate that are in contact with the guest-host liquid crystal layer. The alignment film formed above is a silane coupling film or a polyvinyl alcohol film formed in contact with the quarter-wave plate layer. Alternatively, the alignment film formed on the second substrate side may be a polyimide film formed on the quarter-wave plate layer via a protective film.

According to the present invention, the quarter-wave plate layer uses a side chain type liquid crystalline polymer having methoxyphenyl benzoate as a pendant, and has excellent optical characteristics. That is, the side chain type liquid crystalline polymer into which methoxyphenyl benzoate is introduced has excellent uniaxial orientation, and a good orientation state can be obtained. As a result of uniaxial orientation, stable refractive index anisotropy is obtained, and by using this, a quarter-wave plate layer having excellent optical characteristics can be formed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a partial sectional view showing a basic configuration of a reflection type guest-host liquid crystal display device according to the present invention. As shown in the figure, the present device is an integrated polarization conversion guest-host liquid crystal display device, which is joined to a first substrate 1 disposed on the incident side and a substrate 1 via a predetermined gap and disposed on the reflection side. It is assembled using the second substrate 2. At least a guest-host liquid crystal layer 3, a quarter-wave plate layer 4, and a light reflecting layer 5 are interposed in the gap between the substrates 1 and 2. The guest host liquid crystal layer 3 is located on the incident side of the substrate 1 in the gap and includes, for example, vertically aligned nematic liquid crystal molecules 6 and a dichroic dye 7. The light reflection layer 5 is located on the reflection-side substrate 2 side in the gap. The quarter-wave plate layer 4 is interposed between the guest host layer 3 and the light reflection layer 5.
A counter electrode 8 is formed on the inner surface of the incident-side substrate 1, and a pixel electrode 9 is formed on the inner surface of the reflective-side substrate 2. A signal is applied to the guest-host liquid crystal layer 3 held between the two. Apply voltage. The surfaces of the electrodes 8 and 9 are covered with alignment films 10 and 11, respectively, and the guest-host liquid crystal layer 3 is vertically aligned, for example, as described above. When no voltage is applied, the guest-host liquid crystal display device is in a transmissive state, and when a voltage is applied, it changes to a colored state. In this example, the guest-host liquid crystal layer 3 is vertically aligned, but a horizontal alignment may be selected instead.

The guest-host liquid crystal display device is of an active matrix type, and a thin film transistor 12 is formed on the reflection-side substrate 2 for switching driving of the pixel electrode 9. The thin film transistor 12 is a bottom gate type, and a gate electrode 13, a gate insulating film 14,
The semiconductor thin film 15 and the stopper 16 are stacked.
The thin film transistor 12 is covered with an interlayer insulating film 17, on which a source electrode 18 and a drain electrode 19 are formed by patterning, and connected to the thin film transistor 12 via a contact hole. The light reflection layer 5 described above is also formed by patterning on the interlayer insulating film 17 and has the same potential as the drain electrode 19. Thin film transistor 12
The light reflecting layer 5 having irregularities is covered with a flattening layer 20, on which the above-described quarter-wave plate layer 4 is formed via a base alignment layer 21. Further, the pixel electrode 9 patterned and formed on the quarter-wave plate layer 4 is electrically connected to the drain electrode 19 via the contact hole 22 opened in the quarter-wave plate layer 4 and the flattening layer 20. doing. The opening processing of the contact hole 22 is performed by, for example, photolithography and etching using a positive photoresist. The alignment film 11 is formed by applying a silane coupling agent for vertical alignment to the surfaces of the pixel electrode 9 and the quarter-wave plate layer 4.

As a characteristic feature of the present invention, the quarter-wave plate layer 4 is made of a uniaxially oriented side-chain type liquid crystalline polymer, and has at least methoxyphenylbenzoate as a pendant entering the side chain. One example of the specific chemical structure is shown as a (I) type liquid crystalline polymer in FIG. (I)
The mold has methoxyphenyl benzoate as a pendant entering the side chain. That is, side chains containing methoxyphenyl benzoate are bonded to the alkyl main chain at predetermined intervals. The side chain has a space length of 2 or 6 carbon atoms bonded to the main chain. The liquid crystalline polymer of the type (I) is excellent in uniaxial orientation, and good orientation can be obtained. For this reason, a stable refractive index anisotropic body can be obtained, and excellent optical characteristics (polarization conversion function) can be realized when used as a quarter-wave plate layer. In general, a liquid crystalline polymer changes its phase state depending on the temperature. Specifically, the phase changes from a low temperature side to a high temperature side as a solid phase (glass phase), a liquid crystal phase, and a liquid phase (isotropic phase). Depending on the material, the liquid crystal phase includes a smectic liquid crystal phase and a nematic liquid crystal phase. The liquid crystalline polymer (I) in which methoxyphenylbenzoate is introduced as a pendant directly transitions from a glass phase to a nematic liquid crystal phase without passing through a smectic liquid crystal phase. This transition temperature is 68.5 ° C. when two and six spacers are polymerized one-to-one. In order to uniaxially orient the liquid crystalline polymer, it is necessary to slowly cool the liquid phase from the liquid phase to the liquid crystal phase or leave the liquid crystal polymer in the nematic liquid crystal phase for a certain period of time. in this case,
The (I) type liquid crystalline polymer directly transitions between the glass phase and the nematic liquid crystal phase, so that the range of the phase transition temperature is narrow and stable optical characteristics can be obtained. In addition, about the copolymerization ratio of methoxyphenyl benzoate whose space length is 2 and 6,
As the ratio of the two space lengths increases, the transition point between the glass phase and the nematic liquid crystal phase increases, while the orientation decreases. Therefore, it is practically desirable to set the copolymerization ratio of methoxyphenylbenzoate having two and six space lengths to about 1: 1. Further, as described above, the side chain type liquid crystalline polymer into which methoxyphenyl benzoate is introduced is excellent in orientation and refractive index anisotropy, but has some difficulty in solvent resistance. Therefore, when forming an alignment film for the guest-host liquid crystal layer, it is necessary to consider this point when using an organic solvent.

On the other hand, FIG. 2 (II) shows a side chain type liquid crystalline polymer having biphenyl benzoate as a pendant as a reference example. As another reference example, (II
I) represents a side chain type liquid crystalline polymer having methoxybiphenyl in addition to biphenylbenzoate as a pendant. These (II) type and (III) type liquid crystalline polymers are more excellent in solvent resistance than the (I) type liquid crystalline polymer according to the present invention. However, these (II) types and (I
The type II) liquid crystalline polymer is first transformed from a glass phase to a smectic liquid crystal phase, and then to a nematic liquid crystal phase. Since the smectic liquid crystal phase exists between the glass phase and the nematic liquid crystal phase, the phase transition temperature range between the substantial solid phase and the liquid crystal phase is widened, and stable optical properties can be obtained even below the transition point. Relatively difficult.

Next, a method of manufacturing the reflection type guest-host liquid crystal display device shown in FIG. 1 will be described in detail with reference to FIGS. First, as shown in FIG. 3A, a thin film transistor 12 is formed on the surface of an insulating substrate 2 in an integrated manner. Further, the thin film transistor 12 is connected to the interlayer insulating film 1
Cover with 7. Proceeding to the step (B), the light reflection layer 5 is formed on the interlayer insulating film 17. The light reflection layer 5 has an uneven surface, is light scattering, and can be displayed in white paper. At the same time, the source electrode 18 and the drain electrode 19 connected to the thin film transistor 12 are patterned. Proceeding to the step (C), the thin film transistor 12 and the light reflecting layer 5 having unevenness are covered with a flattening layer 20 made of a transparent acrylic resin or the like. A base alignment layer 21 is formed on the surface. The base alignment layer 21 is made of, for example, a rubbed polyimide film and has a function of giving a desired uniaxial orientation to the quarter-wave plate layer. Proceeding to the step (D), the quarter-wave plate layer 4 is formed on the base alignment layer 21. As described above, the quarter-wave plate layer 4 is made of the (I) type liquid crystalline polymer shown in FIG. 2 and has excellent optical characteristics.

In step (E) of FIG. 4, for example, a photoresist 4a of a polish type is applied to the surface of the quarter-wave plate layer 4. The photoresist 4a is exposed and developed to provide a window 4b aligned with the drain electrode 19. Proceeding to step (F), etching is performed using the patterned photoresist as a mask, and a quarter-wave plate layer 4 and a base alignment layer 2 are formed.
1 and a contact hole 22 penetrating through the flattening layer 20 and communicating with the drain electrode 19. In this etching, dry etching by irradiation with oxygen plasma can be employed. Proceeding to step (G), a transparent conductive film made of ITO or the like is formed on the surface of the quarter-wave plate layer 4.
Further, the transparent conductive film is patterned and processed into the pixel electrode 9. As a result, the pixel electrode 9 is
2 is connected to the drain electrode 19 of the thin film transistor 12. Finally, the process proceeds to step (H), where an alignment film 11 is applied to the surface of the pixel electrode 9 and the exposed surface of the quarter-wave plate layer 4. Specifically, an alignment solution in which a silane coupling agent for vertical alignment is dissolved is applied and dried to form an alignment film 11. Thereafter, the substrate on the incident side on which the counter electrode and the alignment film are formed in advance is joined to the substrate 2 on the reflection side at a predetermined gap, and the guest-host liquid crystal is injected into this gap. The host liquid crystal display is completed.

Next, a method of forming a quarter-wave plate layer will be described in detail with reference to FIG. FIG. 5 shows an example in which a quarter-wave plate layer is formed directly on the substrate surface for easy understanding. First, the alignment step (A) is performed, and the surface of the insulating substrate 51 such as glass or quartz is aligned along a predetermined alignment direction. For example, after a polyimide film is formed on the surface of the substrate 51, the polyimide film may be rubbed along the alignment direction. In some cases, the surface of the substrate 51 may be directly rubbed.
Next, a film forming step (B) is performed, and the side chain type liquid crystalline polymer 52 is formed.
Is applied on the substrate 51 with a predetermined film thickness. In this example, the composition of the type (I) shown in FIG. 2 is used as the side chain type liquid crystalline polymer 52, and methoxyphenyl benzoate is provided as a pendant. This side chain type liquid crystalline polymer undergoes a phase transition between a high temperature side nematic liquid crystal phase and a low temperature side glass phase at a predetermined dislocation point. The (I) type liquid crystalline polymer is dissolved in an appropriate solvent, and is applied to the surface of the substrate 51 which has been subjected to the alignment treatment by spin coating, wire coating, various kinds of printing, or the like. Examples of the solvent include cyclohexanone and methyl ethyl ketone (MEK) 8:
A solution mixed in a ratio of 2 can be used. When performing spin coating, the conditions of the concentration of the solution and the number of spin rotations are appropriately set, and the thickness of the formed coating film is set to a phase difference of λ / 4 (λ represents the wavelength of incident light) in the visible light region. Let it happen. After the solution of the liquid crystalline polymer 52 is applied, it is heated and dried at a temperature sufficient to evaporate the solvent. Finally, a temperature treatment step (C) is performed. The substrate 51 is once heated to a liquid phase (isotropic phase) above the dislocation point and then gradually cooled to room temperature below the dislocation point to form a film of the liquid crystalline polymer 52. Are aligned in the alignment direction to form a quarter-wave plate layer 53. The quarter-wave plate layer 53 is a uniaxial optical thin film. In some cases, it is possible to obtain a desired uniaxial orientation by leaving the film in a nematic liquid crystal phase for a certain period of time. As shown in the drawing, the pendants of the liquid crystal molecules contained in the liquid crystalline polymer 52 are in a random alignment state at the film formation stage, whereas the liquid crystal molecules are aligned along the alignment direction after the temperature treatment step, and Uniaxial optical anisotropy is obtained.

By the way, a liquid crystalline polymer having methoxyphenyl benzoate introduced as a pendant in the side chain is excellent in uniaxial orientation and refractive index anisotropy, but has some difficulty in solvent resistance. About four embodiments taking this point into account are shown in FIGS. For ease of understanding, each embodiment in FIG. 6 is provided with a reference numeral corresponding to the reflection type guest-host liquid crystal display device shown in FIG. However, parts that are not necessary for the description of each embodiment are not shown.
In the embodiment shown in (A), the first substrate 1 and the second substrate 2
Vertical alignment films 10 and 11 are formed on the interface in contact with the guest-host liquid crystal layer 3, respectively, to vertically align the nematic liquid crystal molecules 6 and the dichroic dye 7 included in the guest-host liquid crystal layer 3. The alignment film 11 formed on the second substrate 2 side is made of a silane coupling agent for vertical alignment. The silane coupling agent can be applied directly to the surface of the quarter-wave plate layer 4 as, for example, an ethanol solution. In this case, the quarter wave plate layer 4 is not affected. Since the alignment film 10 formed on the first substrate 1 side has no particular material limitation, a desired vertical alignment material can be selected. For example, a polyimide resin for vertical alignment or a silane coupling agent for vertical alignment can be used.

In the embodiment shown in FIG. 1B, a polyimide resin is used as the vertical alignment film 11 formed on the second substrate 2 side. The polyimide resin is applied in a state of being dissolved in an organic solvent. At this time, since the quarter-wave plate layer 4 made of a liquid crystalline polymer having methoxyphenyl benzoate introduced into the side chain has slightly poor solvent resistance, it is preferable to directly apply a polyimide resin solution thereon. Absent. Therefore, after forming the protective film 30 on the quarter-wave plate layer 4, the alignment film 11 made of a polyimide resin is formed thereon. As the protective film 30, for example, a transparent acrylic resin can be used.

In the embodiment shown in FIG. 1C, horizontal alignment films 10 and 11 are formed at the interfaces of the first substrate 1 and the second substrate 2 in contact with the guest-host liquid crystal layer 3, respectively. , The nematic liquid crystal molecules 6 and the dichroic dyes 7 are horizontally aligned. In this case, the horizontal alignment film 11 formed on the second substrate 2 side is made of a polyvinyl alcohol film. Polyvinyl alcohol is water-soluble and can be applied directly on the quarter-wave plate layer 4 in the form of an aqueous solution. still,
As the horizontal alignment film 11, a silane coupling agent for horizontal alignment may be used instead of the polyvinyl alcohol resin. On the other hand, the alignment film 10 formed on the first substrate 1 side
Since there is no particular limitation on the material, polyvinyl alcohol or a polyimide resin for horizontal alignment can be used.

In the embodiment shown in FIG. 1D, a polyimide resin for horizontal alignment is used as the alignment film 11 formed on the second substrate 2 side. As described above, the polyimide resin is generally applied in the form of a solvent dissolved in an organic solvent. Therefore, it is not preferable to apply directly to the surface of the quarter-wave plate layer 4. Therefore, in this embodiment, the quarter-wave plate layer 4
A protective film 30 made of a transparent acrylic resin or the like is formed thereon, and a polyimide resin for horizontal alignment is formed thereon using this as a base.

[0018]

As described above, according to the present invention,
In the integrated polarization conversion guest-host liquid crystal display device, the quarter-wave plate layer is made of uniaxially oriented side-chain type liquid crystalline polymer, and uses a material having methoxyphenyl benzoate as a pendant entering the side chain. . Since this side chain type liquid crystalline polymer directly transitions between a glass phase and a nematic liquid crystal phase, it has a narrow phase transition temperature range and stable optical properties (refractive index anisotropy).

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view illustrating a configuration of a reflective guest-host liquid crystal display device according to the present invention.

FIG. 2 is a schematic diagram showing a chemical structure of a side-chain type liquid crystalline polymer constituting a quarter-wave plate layer incorporated in a reflection type guest-host liquid crystal display device.

FIG. 3 is a process chart showing a method of manufacturing the reflective guest-host liquid crystal display device shown in FIG.

FIG. 4 is a process drawing showing the same manufacturing method.

FIG. 5 is a process chart showing a method for forming a quarter-wave plate layer.

FIG. 6 is a schematic sectional view showing an embodiment of a reflection type guest host liquid crystal display device according to the present invention.

FIG. 7 is a partial sectional view showing an example of a conventional reflection type guest-host liquid crystal display device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Substrate, 3 ... Guest host liquid crystal layer, 4 ... Quarter wave plate layer, 4a ... Photoresist, 5 ... Light reflection layer, 6 ... Liquid crystal molecule, 7 ... Dichroic dye, 8 ... Counter electrode, 9
... pixel electrode, 10 ... alignment film, 11 ... alignment film, 12 ... thin film transistor, 20 ... planarization layer, 21 ... underlying alignment layer, 2
2 contact hole, 30 protective film

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI G02F 1/137 G02F 1/137 G09F 9/35 385 G09F 9/35 385

Claims (5)

[Claims] 1. A first substrate disposed on an incident side, a second substrate joined to the first substrate via a predetermined gap and disposed on a reflection side, and positioned on the first substrate side in the gap. A guest-host liquid crystal layer to which a dichroic dye is added, a light reflecting layer positioned on the second substrate side in the gap, and a quarter interposed between the guest-host liquid crystal layer and the light reflecting layer. A reflective guest-host liquid crystal display device comprising: a wave plate layer; and electrodes formed on the first substrate side and the second substrate side, respectively, for applying a voltage to the guest host liquid crystal layer. A reflection-type guest-host liquid crystal display device, wherein the wave plate layer is made of a uniaxially oriented side-chain type liquid crystalline polymer, and has at least methoxyphenyl benzoate as a pendant entering the side chain. 2. An alignment film is formed on each of the interfaces of the first substrate and the second substrate that are in contact with the guest-host liquid crystal layer, and the guest-host liquid crystal layer is vertically aligned and formed on the second substrate side. 2. The reflective guest-host liquid crystal display device according to claim 1, wherein the orientation film is a silane coupling film formed in contact with the quarter-wave plate layer. 3. An alignment film is formed on each of interfaces of the first substrate and the second substrate in contact with the guest-host liquid crystal layer, and the guest-host liquid crystal layer is vertically aligned and formed on the second substrate side. 2. The reflective guest-host liquid crystal display device according to claim 1, wherein the alignment film is a polyimide film formed on the quarter-wave plate layer via a protective film. 4. An alignment film is formed on each of the interfaces of the first substrate and the second substrate that are in contact with the guest-host liquid crystal layer, and the guest-host liquid crystal layer is horizontally aligned and formed on the second substrate side. 2. The reflection-type guest-host liquid crystal display device according to claim 1, wherein the alignment film is a silane coupling film or a polyvinyl alcohol film formed in contact with the quarter-wave plate layer. 5. An alignment film is formed on each of the interfaces of the first substrate and the second substrate that are in contact with the guest-host liquid crystal layer, and the guest-host liquid crystal layer is horizontally aligned and formed on the second substrate side. 2. The reflective guest-host liquid crystal display device according to claim 1, wherein the alignment film is a polyimide film formed on the quarter-wave plate layer via a protective film.