JP2003302641A - Liquid crystal device, method for manufacturing liquid crystal device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device wherein ununiformity of the gap between substrates can be prevented or suppressed by using an absolute minimum number of spacers, to provide a method for manufacturing the liquid crystal device, and to provide an electronic equipment provided with the liquid crystal device. <P>SOLUTION: A reflection layers 16 reflecting light are formed partially on a lower substrate 2 and spacers 17 coated with a sticking layer whose sticking force is lowered by UV irradiation are disposed between the lower substrate 2 and an upper substrate 1 selectively above the reflection layers 16. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device, a method of manufacturing a liquid crystal device, and an electronic apparatus including the liquid crystal device, and more particularly to a technique of disposing a spacer between substrates.

[0002]

2. Description of the Related Art As a conventional liquid crystal device, a lower substrate and an upper substrate are adhered to each other at a predetermined interval on a peripheral portion of each substrate via a sealing material, and a liquid crystal layer is sealed between the pair of substrates. There is a configuration. Further, for example, a color filter layer including a red, green, and blue colored layer and a light-shielding layer (black matrix) and a protective layer for protecting the color filter layer are sequentially formed on the lower substrate, and further on the protective layer. There is known a liquid crystal device having a structure in which a transparent electrode is formed on the transparent substrate, a transparent electrode is also formed on the upper substrate, and an alignment film is formed on each transparent electrode.

In such a liquid crystal device, there is a liquid crystal device in which a large number of spherical spacers are arranged between the substrates on which transparent electrodes or alignment films are formed in order to make the intervals between the substrates uniform in the plane of the substrates. As a method of arranging such a spacer between the substrates, a spacer dispersion solution in which the spacer is dispersed in a predetermined solvent is prepared, and this is sprayed by a pressure of a gas such as air or nitrogen, and the spacer is dispersed on one of the substrate surfaces. Wet spraying method of spraying and supplying spacers by carrier gas such as air or nitrogen, charge the spacers naturally or artificially during the supply, and use the electrostatic force to place the spacers on one of the substrates. A dry spraying method of attaching is known.

[0004]

In such a wet spraying method and a dry spraying method, since the spacers are freely dropped on the substrate for spraying, it is difficult to control the spraying position of the spacers. There may be some problems. For example, in a liquid crystal device in which the thickness of the liquid crystal layer is different in each area in the substrate surface, if spacers are scattered over the entire liquid crystal layer, the spacers float in the area where the liquid crystal layer thickness is large, and the substrate In some cases, the effect of spacers that make the intervals uniform may not be exhibited. Originally, the alignment of liquid crystal is likely to be disturbed around the spacers, and it is preferable to keep the number of spacers low in order to improve display characteristics. Therefore, the floating spacer in the region where the liquid crystal layer thickness is large in which the effect of the spacer is not exhibited is
Disturbance of liquid crystal alignment around the spacers may occur, which may lead to deterioration of image quality due to light leakage or the like, and eventually to deterioration of display characteristics of the liquid crystal device.

The present invention has been made in view of the above problems, and a liquid crystal device capable of preventing or suppressing nonuniformity of a substrate interval by using a minimum necessary spacer, a method of manufacturing the liquid crystal device, and Aims to provide an electronic device including the liquid crystal device.

[0006]

In order to solve the above problems, a liquid crystal device of the present invention is a liquid crystal device in which a spacer is arranged between a pair of substrates sandwiching a liquid crystal layer, and a spacer is provided between the pair of substrates. Is a reflective layer that partially reflects light is formed in the surface of the substrate, and the spacer is covered with a fixing layer whose adhesion is reduced by ultraviolet irradiation, and is selectively disposed above the reflecting layer. It is characterized by

In the liquid crystal device having the reflective layer partially formed in the plane of the substrate as described above, the liquid crystal layer thickness in the reflective layer forming region is smaller than that in the non-forming region by the layer thickness of the reflective layer. Become. Since the spacers are selectively arranged in the region where the liquid crystal layer thickness is relatively small and the fixing layer is coated on the spacers, problems such as floating of the spacers are less likely to occur. In addition, since the fixing layer coated on the spacer has a structure in which its fixing force is reduced by irradiation with ultraviolet rays, for example, after the spacers are scattered on the substrate surface at the time of manufacturing, ultraviolet rays are selectively applied to the non-formed area of the reflective layer. By irradiating, it is possible to selectively reduce the fixing force with respect to the spacers scattered in the non-formed area of the reflective layer, and thus it is possible to selectively dispose the spacer in the reflective layer formed area. Become.

That is, according to the present invention, it is possible to simply and surely dispose spacers selectively in the reflection layer forming region (that is, the liquid crystal layer thin layer region), and the substrate spacing is reduced by the minimum necessary spacers. It becomes possible to maintain the uniformity in the plane of the substrate. Further, since no extra spacer is provided in the spacer non-forming region, it is possible to suppress the occurrence of liquid crystal alignment defects around the spacer. In the present invention, not only the spacer is provided only above the reflective layer, but the above effect is exhibited not only by providing a relatively larger number of spacers in the reflective layer forming region than in the region where the reflective layer is not formed. It is possible.

In the above liquid crystal device, the area where the reflective layer is formed can be used as the reflective display area, and the area where the reflective layer is not formed can be used as the transmissive display area. In this case, the liquid crystal device is a transflective display type liquid crystal device capable of performing either reflective display or transmissive display.

In such a transflective liquid crystal device,
In reflective display and transmissive display, the number of times light that contributes to display passes through the liquid crystal layer is different. Specifically, in transmissive display, light from the backlight passes through the liquid crystal layer once, whereas in reflective display, The light incident from the front passes through the liquid crystal layer twice when it enters the reflective layer and when it is reflected. Therefore, the retardation value is different in each display area, and high contrast display may not be performed in each area. Therefore, by providing a translucent insulating layer only in the reflective display region, or by forming a translucent insulating layer having a relatively thicker layer than the transmissive display region in the reflective display region, the retardation value is more optimal in each region. Can be converted.

Also in such a semi-transmissive reflective display type liquid crystal device, as described above, by selectively disposing the spacer above the reflective layer, that is, above the translucent insulating layer, the minimum required It becomes possible to keep the substrate spacing more uniform in the plane of the substrate by the spacer. Further, since no extra spacer is provided in the spacer non-forming region, it is possible to suppress the occurrence of liquid crystal alignment defects around the spacer.

The number of the spacers per unit area in the entire liquid crystal layer can be 50 / mm ² or more, and the number per unit area in the reflective layer can be 400 / mm ² or less. The variation in the substrate spacing depends on the spacer density in the entire liquid crystal layer, and when it is less than 50 spacers / mm ² , the substrate spacing may vary by 0.1 μm or more and display unevenness may occur. On the other hand, due to the disposition of excess spacers, the occurrence of liquid crystal alignment defects around the spacers depends on the density of the spacers in the reflective display area. If the number of spacers exceeds 400 / mm ² , the spacers become excessive and liquid crystal alignment occurs. The contrast may decrease due to the influence of defects. The number of liquid crystal layers per unit area is preferably 150 /
The number per unit area of the reflective layer may be preferably not less than 300 mm ^{2 and not} more than 300 mm ² / mm ² .

Next, a color filter is partially provided on the liquid crystal layer side of the reflection layer within the substrate surface, and a spacer is provided.
It can be selectively disposed in the color filter formation region above the reflective layer. When a color filter is provided on the liquid crystal layer side of the reflective layer, the light passes through the color filter twice during reflective display, while the light passes through the color filter once during transmissive display and is used for display. There may be a difference in shade of color in the area. Therefore, by partially forming the color filter on the liquid crystal layer side of the reflective layer in the substrate surface as described above, the amount of light passing through the color filter during reflective display is reduced and the color of each display area is reduced. Difficulty in light and shade. Further, since the color filter is partially formed in the reflective layer formation region (reflection display region) as described above, the liquid crystal layer thickness in the color filter formation region becomes relatively small. Therefore, in the present invention, spacers are selectively disposed in the color filter formation region, and the minimum required spacers are used to keep the substrate spacing more even within the substrate plane, thereby suppressing the occurrence of liquid crystal alignment defects around the spacers. It was configured to do.

The transparent insulating layer for reducing the thickness of the liquid crystal layer in the reflective display area can be formed on the liquid crystal layer side of the color filter and can function as a protective layer (overcoat) for the color filter. . In this case, the protective layer (overcoat) of the color filter can have both a function as a protective layer of the color filter and a function of controlling the liquid crystal layer thickness of the reflective display region and the transmissive display region. Therefore, it is not necessary to form a translucent insulating layer in the reflective display area. Even in a liquid crystal device in which spacers are selectively arranged based on the presence or absence of color filter formation, the number of spacers to be arranged is 50 / mm ² or more per unit area in the liquid crystal layer, as described above.
In addition, the number per unit area in the color filter formation region can be 400 / mm ² or less.

Next, the liquid crystal device of the present invention can be manufactured by the following manufacturing method. That is, the method for manufacturing a liquid crystal device of the present invention includes a reflective layer forming step of partially forming a reflective layer on at least one substrate of a pair of substrates, and a spacer that disperses spacers on the substrate on which at least the reflective layer is formed. A spraying step, a substrate heating step of heating the substrate on which the spacers have been sprayed, an ultraviolet irradiation step of irradiating the region where the spacer is to be removed with ultraviolet rays after the heating step, and a spacer whose adhesive strength has been reduced by ultraviolet irradiation is selectively And a spacer removing step of removing the spacer.

In this case, the reflective layer is formed on the substrate, the spacers are dispersed, and then the spacers are fixed by heating,
After that, the fixing force is reduced by irradiating the region where the spacer is desired to be removed with ultraviolet light, and the spacer having the reduced fixing force is selectively removed to selectively select the spacer in a predetermined region (reflection display region, color filter forming region). It is supposed to be installed in. The fixing layer can be made of a material which is fixed to the substrate by heating and whose fixing force is lowered by irradiation with ultraviolet rays, and specifically, for example, it can be realized by adopting a thermoplastic acrylic resin.

Further, in the spacer spraying step, for example, a method of spraying spacers suspended in a solvent in a state of being dispersed in a gas from above the substrate and non-selectively spraying can be adopted. Further, the ultraviolet irradiation step can selectively perform ultraviolet irradiation on the region where the spacer is desired to be removed by mask exposure, and the spacer removal step after the ultraviolet irradiation can be performed by, for example, air blow or liquid cleaning.

Next, the region where the spacer is desired to be removed can be a region where the reflective layer is not formed (transmissive display region). In that case, in the step of irradiating the ultraviolet rays, the substrate on which the spacer is scattered using the reflective layer as a mask. It is possible to irradiate ultraviolet rays from the back surface side of the above and selectively irradiate ultraviolet rays to the non-formation area of the reflective layer. In this way, the reflective layer provided in the reflective display area can be used as a mask to selectively irradiate ultraviolet rays only in the transmissive display area. Therefore, it is not necessary to separately form a mask, and the manufacturing method is simplified. In this case, the spacers in the transmissive display area irradiated with ultraviolet rays will be removed in the subsequent spacer removing step.

Further, the electronic equipment of the present invention is characterized by including the above liquid crystal device as a display device, for example. By thus providing the liquid crystal device of the present invention,
It is possible to provide an electronic device with excellent display quality.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. [Liquid Crystal Device] The liquid crystal device of this embodiment described below is a simple matrix type transflective liquid crystal device. Figure 1
Is a cross-sectional view schematically showing the structure of the liquid crystal device of the present embodiment, in which the upper side in the drawing is the viewing side (observer side) on which external light such as natural light or illumination light used for reflective display is incident, The lower side of the drawing is a case where the light source side on which light from an internal light source used for transmissive display enters. Further, in the drawings, in order to make each layer and each member recognizable in the drawing, the scale is different for each layer and each member.

As shown in FIG. 1, a liquid crystal device 100 of this embodiment has a super-twisted nematic liquid crystal (between a top substrate 1 and a bottom substrate 2 made of transparent glass or the like which are vertically opposed to each other. It has a basic structure in which a liquid crystal layer 3 made of STN) is sandwiched. Although not shown in the drawing, a sealing material is actually interposed on the peripheral side of the substrates 1 and 2, and the liquid crystal layer 3 is surrounded by the substrates 1 and 2 and the sealing material. It is sandwiched between the substrates 1 and 2 in a sealed state. Further, a backlight (light source) 4 including a light source, a light guide plate and the like is provided below the lower substrate 2.

A retardation plate 12 and a polarizing plate 13 are disposed on the upper surface side (observer side) of the upper substrate 1 and the lower substrate 2
Also on the lower surface side (internal light source side) of the retardation plate 14 and the polarizing plate 15.
And are arranged. The polarizing plates 13 and 15 are external light entering from the upper surface side and the backlight 4 entering from the lower surface side.
Only the linearly polarized light in one direction is transmitted with respect to the light of 1, and the phase difference plates 12 and 14 convert the linearly polarized light transmitted through the polarizing plates 13 and 15 into circularly polarized light (including elliptically polarized light). Therefore, the polarizing plates 13 and 15 and the phase difference plates 12 and 14 function as circularly polarized light incident means. In the present embodiment,
The side provided with the backlight 4 is the lower side, and the side on which one external light enters is the upper side.

On the liquid crystal layer 3 side of the lower substrate 2, a plurality of reflective layers 16 are provided in a matrix at a predetermined interval. The reflective layer 16 is provided with openings 16a at predetermined intervals, and the openings 16a are rectangular in plan view so as to be spaced apart from each other in the lateral direction of the paper of FIG. A plurality of parts are formed in a divided manner. The reflective layer 16 is made of a metal material such as Al and Ag having a light reflectivity, that is, a high reflectance, and is formed in a rectangular frame shape in a plan view.

A plurality of colored layers (R, G, B) and a light shielding layer (black matrix) 10 are provided on the upper side of the reflective layer 16.
A color filter 10 including a and a is provided. In this case, the colored portion is composed of R (red), G (green) and B (blue), each colored portion constitutes a dot, and these dots are aggregated to form a pixel having a substantially square shape in plan view. Has been done. In the structure of the color filter 10 shown in FIG. 1, the colored layers are repeatedly arranged in the order of R (red), G (green), and B (blue), but the arrangement order of these colored layers is an example. Any arrangement such as random arrangement, mosaic arrangement, or arrangement in another order may be used.

On the upper layer of the color filter 10, an overcoat (transparent insulating layer) 11 for eliminating a step formed by the colored layers (R, G, B) and the light shielding layer (black matrix) is provided. It is formed over the entire surface of 10. The liquid crystal device 100 of the present embodiment
Is a semi-transmissive reflective liquid crystal device in which the reflective layer 16 is partially provided in the substrate surface, and the overcoat 11 is formed to a thickness that cannot eliminate the step due to the formation of these reflective layers 16. Has been done.

The upper layer of the overcoat 11 is made of ITO (In
A scan electrode 5 made of dium-tin-oxide, etc. is formed, and an alignment film (not shown) is formed on the scan electrode 5 on the liquid crystal layer 3 side so as to cover the scan electrode 5. The scanning electrodes 5 are formed in stripes so as to extend in the direction parallel to the paper surface of FIG. 1 (horizontal direction in the paper surface of FIG. 1) and spaced apart from each other in the direction perpendicular to the paper surface. The alignment film is formed by subjecting a polymer material film such as polyimide to a predetermined rubbing treatment.

Here, the layer thickness of the reflective layer 16 is 0.1 μm to
0.4 μm (eg 0.2 μm), color filter 10
Is 1 μm to 4 μm (for example, 1.5 μm), and the overcoat 11 is 0.5 μm to 6 μm (for example, 2.
0 μm) and the layer thickness of the liquid crystal layer 3 is 2 μm to 8 μm (for example, 4.2 μm).

On the other hand, ITO is provided on the liquid crystal layer 3 side of the upper substrate 1.
A signal electrode 6 made of (Indium-Tin-Oxide) or the like is formed, and on the liquid crystal layer 3 side of the signal electrode 6, an alignment film (not shown) is formed so as to cover the signal electrode 6. The signal electrodes 6 are formed in stripes so as to extend in the direction perpendicular to the paper surface of FIG. 1 and at intervals in the direction parallel to the paper surface. The alignment film is formed by subjecting a polymer material film such as polyimide to a predetermined rubbing treatment.

As described above, a plurality of substrates are provided between the lower substrate 2 having the reflective layer 16, the color filter 10, the overcoat 11, the scanning electrodes 5 and the like laminated thereon and the upper substrate 1 having the signal electrodes 6 and the like laminated thereon. The liquid crystal layer 3 is sandwiched via the spacer 17. In the liquid crystal device 100 of the present embodiment, unevenness is formed on the surface of the lower substrate on the liquid crystal layer 3 side due to the partial formation of the reflective layer 16. Due to this unevenness, the layer thickness of the liquid crystal layer 3 is partially within the substrate surface. Have different configurations. Therefore,
The spacer 17 is selectively arranged in a region where the liquid crystal layer thickness is small, that is, in a region where the reflective layer 16 is provided.

By the way, in the liquid crystal device 100, a region used for display includes a reflective display region R and a transmissive display region T, and these display portions are formed with different liquid crystal layer thicknesses. Specifically, the area in which the reflective layer 16 is provided is the reflective display area R, and the reflective display area R is the reflective layer 1.
The thickness of the liquid crystal layer is relatively thin under the influence of 6, and therefore the spacer 17 is provided in the liquid crystal layer 3 of the reflective display region R. On the other hand, the region where the reflective layer 16 is not provided is the transmissive display region T, and since the reflective layer 16 is not formed in the transmissive display region T, the liquid crystal layer is formed relatively thick, and therefore the transmissive display region T is formed. The spacer 17 is not provided in the liquid crystal layer 3 in the display area T.

The spacer 17 is mainly composed of translucent glass or resin, and is a material that can be fixed to the substrate by heating or the like on its surface layer, and its fixing force is lowered by irradiation of ultraviolet rays. The one coated with a fixing layer made of a material is used. As such a fixing layer, for example, an acrylic resin can be used.

Further, the spacer 17 has a reflective display region R.
And the number of transparent display areas T per unit area is 50.
Pieces / mm is ² or more, have been and are the number per unit area in the reflective display region R and 400 / mm ² or less. The spacers 17 have such a density that the reflective display area R is formed.
Since the liquid crystal layer is selectively disposed on the substrate, it is possible to suppress the occurrence of liquid crystal alignment failure due to the influence of the spacer 17 while keeping the liquid crystal layer thickness uniform within the substrate surface.
The number per unit area in the reflective display region R and the transmissive display region T is preferably 150 / mm ² or more, and the number per unit area in the reflective display region R is preferably 300 / mm ² or less. it can.

Next, the reflective layer 16 is formed in the reflective display region R, and the opening edge of the opening 16a of the reflective layer 16 serves as the boundary between the reflective display region R and the transmissive display region T. Therefore, the transmissive display area T is formed in the opening 16a, light is incident from the backlight 4 through the opening 16a, and the incident light passes through the liquid crystal layer 3 and is used for transmissive display. There is. On the other hand, external light such as sunlight or illumination light incident from above (outside) the upper substrate 1 passes through the liquid crystal layer 3 and is then reflected by the reflective layer 16, and the reflected light passes through the liquid crystal layer 3 again. The light is emitted above (outside) the upper substrate 1 and provided for reflective display.

Here, the transflective display type liquid crystal device 10 is shown.
At 0, the number of times the light contributing to the display passes through the liquid crystal layer 3 is different between the reflective display and the transmissive display. Specifically, as described above, in the transmissive display, the light from the backlight 4 is emitted from the opening 16a to the liquid crystal. In the reflective display, light incident from the front passes through the liquid crystal layer 3 twice, when the light is incident on the reflective layer 16 and when it is reflected, while the layer 3 is passed once. Therefore, the retardation values in the reflective display region R and the transmissive display region T are different, and there is a possibility that high-contrast display cannot be performed in each region.

Therefore, as in the liquid crystal device 200 shown in FIG. 2, an overcoat 211 having a layer thickness relatively larger than that of the transmissive display region T is formed in the reflective display region R so that the retardation values are set in the respective regions R and T. Can be made more uniform. It is also possible to provide an overcoat only in the reflective display region R to make the retardation values uniform.

Further, as shown in FIG. 1, when the color filter 10 is provided on the liquid crystal layer 3 side of the reflective layer 16, light passes through the color filter 10 twice during reflective display.
At the time of transmissive display, light passes through the color filter 10 once and is used for display, so that there may be a difference in shades of colors in the display regions R and T. Therefore, as in the liquid crystal device 300 shown in FIG. 3, the color filter 310 is partially formed in the substrate surface, and in particular, by providing a non-formation region of the color filter 310 in the reflective display region R, a reflective display is performed. At color filter 311
The amount of light passing therethrough per one time is reduced (preferably half), and it is difficult for a difference in color shade to occur between the display regions R and T.

In FIG. 3, a non-formed area is provided for each dot for each colored layer R, G, B of the color filter 310, but this non-formed area is not necessarily the colored layers R, G, B.
It is not necessary to provide it in all, and it is also possible to provide it in at least one of the colored layers R, G, and B. Further, in the liquid crystal device 300 of FIG. 3, a non-formation area is formed in the reflective display area R for the color filter 310.
At the color filter 310,
1 to the color filter 310 by reducing the layer thickness of
It is also possible to relatively reduce the amount of light passing per turn.

The liquid crystal devices 100 and 20 shown in FIGS.
In this embodiment, since the spacer 17 including the fixing layer is used as in the case of 0, 300, the liquid crystal layer 3 is stably fixed particularly in the reflective display region R, and for example, when vibration or stress is applied to the panel. In addition, it is possible to prevent or suppress the in-plane nonuniformity of the substrate spacing without moving to the transmissive display region T.

Further, since the spacer 17 has a fixing layer on its surface, which can be fixed to the substrate by heating and whose fixing force is lowered by irradiation of ultraviolet rays, for example, in the step of disposing the spacer 17 on the substrate. The spacer 17 is formed on the reflective display region R by the following simple method.
It is possible to selectively dispose of only in. That is,
After the spacers 17 are randomly placed on the substrate, the spacers 17 are heated to fix the spacers 17 to the substrate,
Next, by irradiating only the transmissive display region T with ultraviolet rays, the adhesive force of the spacers 17 adhered to the transmissive display region T is reduced, and the spacers 17 having the reduced adhesive force are removed. It is possible to selectively dispose the spacer 17 in the.

As described above, the structure of the spacer is characteristic in the present embodiment, but the present invention is not limited to the above-mentioned embodiment, and each claim is not limited to the range described in each claim. It is not limited to the wording of the section, and it can be appropriately added to the range that can be easily replaced by those skilled in the art and based on the knowledge that the person skilled in the art usually has. For example, although a simple matrix type liquid crystal device is illustrated in the present embodiment, for example, an active matrix type liquid crystal device can also adopt the configuration according to the present invention. Further, in the present embodiment, the liquid crystal layer 3
As a super twisted nematic liquid crystal (ST), which requires a uniform substrate spacing (liquid crystal layer thickness).
Although N) is used, it is also applicable to a liquid crystal device having a liquid crystal layer made of a nematic liquid crystal or other liquid crystal material.

[Electronic Equipment] Next, specific examples of electronic equipment including any of the liquid crystal devices described in the above embodiments will be described.

FIG. 4A is a perspective view showing an example of a mobile phone. In FIG. 4A, reference numeral 500 indicates a mobile phone main body, and reference numeral 501 indicates the liquid crystal device 10 of the above embodiment.
The liquid crystal display part provided with either 0, 200, or 300 is shown.

FIG. 4B is a perspective view showing an example of a portable information processing device such as a word processor and a personal computer. Figure 4
In (b), reference numeral 600 is an information processing device and reference numeral 60.
Reference numeral 1 is an input unit such as a keyboard, reference numeral 603 is an information processing main body, and reference numeral 602 is the liquid crystal devices 100 and 20 of the above embodiment.
The liquid crystal display part provided with either 0 or 300 is shown.

FIG. 4C is a perspective view showing an example of a wrist watch type electronic device. In FIG. 4C, reference numeral 700 indicates a watch body, and reference numeral 701 indicates a liquid crystal display unit including any of the liquid crystal devices 100, 200 and 300 of the above-described embodiment.

As described above, each of the electronic devices shown in FIGS. 4A to 4C has the liquid crystal device 100,
Since the electronic device is equipped with either 200 or 300, it is an electronic device with less display unevenness, high contrast and excellent display quality.

[Manufacturing Method of Liquid Crystal Device] Next, several manufacturing methods of the liquid crystal device shown in the above embodiment will be described with reference to FIGS. First, FIGS. 5 and 6 show a method of manufacturing the liquid crystal device 100 shown in FIG.
FIG. 3 is a schematic cross-sectional view showing an example of each step, and the manufacturing method in this case is also applicable to the liquid crystal device 200 shown in FIG. 2. In the method of manufacturing the liquid crystal device 100, first, as shown in FIG. 5A, a reflective layer 16 is formed in a predetermined pattern in a region corresponding to the reflective display region R on the lower substrate 2 by, for example, a photolithography method. To form. Specifically, only a region corresponding to the reflective display region R is formed by depositing Al on the entire surface of the lower substrate 2 by vacuum deposition or sputtering, and performing steps such as resist formation, exposure, development, etching, and resist stripping. Then, the reflective layer 16 is selectively patterned.

Next, as shown in FIG. 5B, the reflective layer 1
The color filter 10, the light shielding layer 10 a, the overcoat 11, and the scanning electrode 5 are laminated on the lower substrate 2 on which 6 is formed. First, the color filter 10, the light shielding layer 10a, and the overcoat 11 can be formed as follows.
That is, for example, chromium is formed in a predetermined pattern on the lower substrate 2 on which the reflective layer 16 is formed by a photolithography method, and then a colored resin is formed between the chromium films (light shielding layers) by the same photolithography method. The film is formed in a pattern having an intervening state. Do this for each color (R, G, B),
Further, a transparent resin as an overcoat is applied so as to cover the entire surface of the substrate, whereby the color filter 10, the light shielding layer 10a, and the overcoat 11 are formed.

Next, the scan electrode 5 can be formed as follows. That is, ITO (Indium-Tin-Oxid)
After e) is formed on the entire surface of the overcoat 11 by vacuum vapor deposition or sputtering, it is patterned into a predetermined stripe pattern by photolithography. In the present embodiment, the pattern is formed in a corresponding stripe shape extending in the direction parallel to the paper surface of FIG. 5B and spaced from each other in the direction perpendicular to the paper surface. It should be noted that an alignment film obtained by rubbing a polyimide film is formed on the surface of the scanning electrode 5.

Thus, the color filter 10 and the light shielding layer 1 are
0a, the overcoat 11, and the scanning electrode 5 are formed on the entire surface of the lower substrate 2 as shown in FIG.
Is scattered at random. As a spacer spray method,
For example, spacers 17 dispersed in gas (spray medium)
Can be sprayed from above the substrate by a spraying method, and can be randomly dispersed on the surface of the substrate. As another method, for example, a method of spraying the spacer 17 suspended in a solvent (coating medium) together with a gas from above the substrate by a spray method can be used.

After spraying the spacers 17, the substrate is heated to a predetermined temperature (for example, 120 ° C.). By this heating,
The fixing layer formed on the surface of the spacer 17 is plasticized,
By removing this heat, the spacer 17 can be fixed on the scanning electrode 5.

After fixing the spacers 17 as shown in FIG.
As shown in (c), ultraviolet rays are irradiated from the back surface side of the lower substrate 2, that is, the side of the lower substrate 2 opposite to the side on which the reflective layer 16 is formed. The adhesive strength of the spacer 17 is reduced by irradiation of ultraviolet rays. In this embodiment, however, the reflective layer 16 functions as a mask, and the spacer 17 adhered to the area corresponding to the reflective display area R is exposed to ultraviolet light. Not irradiated. Therefore, only the spacers 17 fixed to the area corresponding to the transmissive display area T are selectively irradiated with ultraviolet rays, and the fixing force thereof is reduced.

After irradiating the back surface of the lower substrate 2 with ultraviolet rays in this way, by air blowing or washing with a liquid,
As shown in FIG. 6A, the spacers 17 having a reduced sticking force are selectively removed, so that the spacers 17 in the region corresponding to the transmissive display region T are removed and the reflective display region R is removed.
It is possible to obtain a pre-substrate in which the spacer 17 is fixed only in the region corresponding to.

After that, the pre-substrate having the spacers 17 selectively arranged and the counter-side pre-substrate having the signal electrodes 6 (with the alignment film) laminated on the upper substrate 1 are sandwiched with the STN type liquid crystal material between the two substrates. Bonding is done while making it. Then, the retardation plates 12 and 14 and the polarizing plates 13 and 15 are laminated on the opposite sides of the substrates 1 and 2 from the liquid crystal layer 3 to obtain the liquid crystal cell shown in FIG. 6B. The liquid crystal device 100 shown in FIG. 1 is manufactured by the manufacturing method including the steps described above. Note that when the liquid crystal device 200 shown in FIG. 2 is manufactured, the reflective display region R
Only the thickness of the overcoat 11 is increased.

Next, a modified example of the method of manufacturing the liquid crystal device of the above embodiment will be described. That is, the transparent display area T
In the step of irradiating the region corresponding to the area with ultraviolet rays to selectively reduce the fixing force of the spacer 17, as shown in FIG.
It is also possible to form ultraviolet rays above the substrate 7, that is, on the side of the lower substrate 2 where the reflective layer 16 is laminated, and selectively irradiate ultraviolet rays. In this case, the region corresponding to the transmissive display region T is selectively irradiated with ultraviolet rays from above the substrate via the photomask 51. Although FIG. 7 shows an example relating to the ultraviolet irradiation step in manufacturing the liquid crystal device 100 shown in FIG.
Similarly, in the step of irradiating the liquid crystal device 200 with an ultraviolet ray, it is possible to form the photomask 51 above the substrate and perform selective ultraviolet ray irradiation.

FIG. 8 shows the liquid crystal device 30 shown in FIG.
It is a cross-sectional schematic diagram which shows the outline of the ultraviolet irradiation process in the manufacturing process of No. 0. In the liquid crystal device 300, the reflective layer 16
Even in the reflective display region R in which the spacers are formed, since the spacers 17 are not arranged in the regions where the color filters 310 are not formed, the lower substrate 2 as shown in FIGS.
The exposure from the back side of can not be adopted. Therefore, in this case, as in FIG. 7, the photomask 5 having a predetermined pattern is formed.
2 is formed above the spacer 17 to selectively irradiate ultraviolet rays only in the reflective display region R in which the reflective layer 16 is formed and in which the color filter 10 is formed.

In either method, the scattered spacers are heated and fixed to the substrate on which the color filters, electrodes, etc. are laminated, and then ultraviolet rays are selectively applied to the region below or above the substrate where the spacers are to be removed. It is supposed to irradiate. Then, the spacers irradiated with ultraviolet rays are selectively removed by air blowing or liquid cleaning, whereby the spacers can be arranged in a predetermined region (a region where the liquid crystal layer thickness is relatively small).

[0057]

As described above, according to the present invention, the spacers are selectively disposed in the reflective layer forming region where the liquid crystal layer thickness is relatively small, and the spacers are covered with the fixing layer. Problems such as floating of the water are less likely to occur.
In addition, since the fixing layer coated on the spacer has a structure in which its fixing force is reduced by irradiation with ultraviolet rays, for example, after the spacers are scattered on the substrate surface at the time of manufacturing, ultraviolet rays are selectively applied to the non-formed area of the reflective layer. By irradiating, it is possible to selectively reduce the fixing force with respect to the spacers scattered in the non-formed area of the reflective layer, and thus it is possible to selectively dispose the spacer in the reflective layer formed area. Become.

Further, in a liquid crystal device having a reflective layer as in the present invention, when it is desired to selectively form spacers in the reflective layer forming region, the reflective layer is used as a mask to form a spacer dispersed substrate. It is possible to irradiate ultraviolet rays from the back surface side (side different from the side on which the reflective layer is formed), and selectively irradiate ultraviolet rays to the region where the reflective layer is not formed. In this way, since it is possible to selectively irradiate ultraviolet rays to the reflection layer non-forming region using the reflection layer as a mask,
There is no need to separately form a mask, and the manufacturing method is simplified.

Therefore, according to the present invention, it is possible to simply and surely dispose the spacers selectively with respect to the reflection layer forming region, and to keep the substrate spacing more uniform in the substrate surface by the minimum necessary spacers. Is possible. Further, since no extra spacer is provided in the spacer non-forming region, it is possible to suppress the occurrence of liquid crystal alignment defects around the spacer.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional schematic view showing the configuration of a transflective liquid crystal device which is an embodiment of a liquid crystal device of the present invention.

FIG. 2 is a schematic partial cross-sectional view showing a modification of the transflective liquid crystal device of FIG.

3 is a schematic partial cross-sectional view showing a modification of the transflective liquid crystal device of FIG.

FIG. 4 is a perspective view showing some examples of electronic devices according to the present invention.

FIG. 5 is an explanatory view showing an example of a step of the method of manufacturing the liquid crystal device according to the present embodiment.

FIG. 6 is an explanatory view showing an example of one step of the manufacturing method following FIG.

FIG. 7 is an explanatory diagram showing a modification of the method for manufacturing the liquid crystal device of the present embodiment.

FIG. 8 is an explanatory diagram showing a modified example of the method for manufacturing the liquid crystal device of the present embodiment.

[Explanation of symbols]

1 Upper substrate 2 Lower substrate 3 Liquid crystal layer 16 Reflective layer 17 Spacer 100,200,300 Liquid crystal device R reflective display area T transparent display area

Continued front page    F-term (reference) 2H042 DA01 DA12 DA22 DC02 DE00                 2H048 BA02 BA45 BB02 BB08 BB42                 2H089 LA03 QA16 RA10 TA04 TA12                       TA13 TA15 TA17 TA18                 2H091 FA02Y FA08X FA08Z FA14Z                       FA35Y FA41Z FB04 GA06                       GA08 HA10 LA30

Claims (9)

[Claims] 1. A liquid crystal device in which a spacer is arranged between a pair of substrates sandwiching a liquid crystal layer, and a reflective layer for reflecting light is partially formed between the pair of substrates in the plane of the substrate. The liquid crystal device, wherein the spacer is covered with a fixing layer whose fixing force is lowered by irradiation of ultraviolet rays, and is selectively disposed above the reflecting layer. 2. The liquid crystal device according to claim 1, wherein the area where the reflective layer is formed is a reflective display area, and the area where the reflective layer is not formed is a transmissive display area. . 3. In the reflective display area, a translucent insulating layer is formed only in the reflective display area, or a translucent insulating layer having a relatively thicker thickness than the transmissive display area is formed. The liquid crystal device according to claim 1, wherein the liquid crystal device is a liquid crystal device. 4. The number of the spacers per unit area of the entire liquid crystal layer is 50 / mm ² or more, and the number of spacers per unit area of the reflective layer is 400 / m 2.
The liquid crystal device according to claim 1, wherein the liquid crystal device has a size of m ² or less. 5. A color filter is partially provided in the substrate surface on the liquid crystal layer side of the reflection layer, and the spacer is selectively arranged in the color filter formation region above the reflection layer. The liquid crystal device according to any one of claims 1 to 4, wherein the liquid crystal device is provided. 6. The liquid crystal device according to claim 5, wherein the translucent insulating layer is formed on the liquid crystal layer side of the color filter and functions as a protective layer of the color filter. 7. The method for manufacturing a liquid crystal device according to claim 1, wherein the reflective layer is formed by partially forming the reflective layer on at least one substrate of the pair of substrates. A step, and a spacer spraying step of spraying the spacer on the substrate having at least the reflective layer formed thereon,
A substrate heating step of heating the substrate on which the spacers are scattered, an ultraviolet irradiation step of irradiating the region where the spacer is to be removed with ultraviolet rays after the heating step, and a spacer whose adhesive strength is reduced by the ultraviolet irradiation is selectively A method of manufacturing a liquid crystal device, comprising: a spacer removing step of removing the spacer. 8. The region where the spacer is desired to be removed is a region where the reflective layer is not formed, and in the ultraviolet irradiation step, ultraviolet rays are irradiated from the back surface side of the substrate on which the spacers are scattered using the reflective layer as a mask. 8. The method of manufacturing a liquid crystal device according to claim 7, wherein the region where the reflective layer is not formed is selectively irradiated with ultraviolet rays. 9. An electronic apparatus comprising the liquid crystal device according to claim 1. Description: