JP2000171785A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of air bubble from various formed thin films, especially from an organic material film of a smoothing layer, even if the film is kept for a long period or under application of external force at the time of use. SOLUTION: The liquid crystal display device is constructed by enclosing a liquid crystal LC within a confronted gap between a pair of substrates SUB1, SUB2, on their inside thin films of organic materials (a smoothing layer OC, upper and lower alignment layers ORI2, 1) being formed, and being stuck on their peripheries with a sealant SL. The substrate, on which the thin films of organic materials are formed, is subjected to 10 deg.C/min temperature elevation in a heating and gas generating device with 1×10-6 Pa. ultimate degree of vacuum. The thin films of organic materials with <=70,000 integrated quantity of detected ion intensity of carbon dioxide measured every other degree from room temperature to 250 deg.C are used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device which suppresses gas generation from thin films of various organic materials formed on the inner surface of a substrate to prevent display defects.

[0002]

2. Description of the Related Art In recent years, thin, lightweight and low power consumption display devices using liquid crystal display elements have been widely used as display devices for personal computers, word processors, and other information devices.

A liquid crystal display element basically has a matrix formed by a large number of electrodes arranged in a horizontal direction and a vertical direction, and a liquid crystal layer between the horizontal and vertical electrodes. A two-dimensional image is displayed by forming pixels.

This type of liquid crystal display element has a so-called simple matrix system in which a predetermined pixel is selected at the timing of a pulse applied to horizontal and vertical electrodes, and a transistor for each pixel formed at the intersection of the vertical and horizontal electrodes. There is a so-called active matrix system in which non-linear elements such as are arranged and a predetermined pixel is selected.

For example, an active matrix type liquid crystal display device has a non-linear element (switching element) provided for each of a plurality of pixel electrodes arranged in a matrix. Theoretically, the liquid crystal in each pixel is always driven (duty ratio: 1.0).
The active matrix system has a better contrast than the so-called simple matrix system which employs a time-division driving system, and is becoming an indispensable technology especially in a color liquid crystal display device. A typical switching element is a thin film transistor (TFT).

Incidentally, an active matrix type liquid crystal display device using thin film transistors is disclosed in, for example, Japanese Patent Application Laid-Open No. 63-309921 or "1.
2.5-inch active matrix color liquid crystal display "(Nikkei Electronics, pp. 193-210,
December 15, 1986, published by Nikkei McGraw-Hill Company).

In a color liquid crystal display device, a plurality of (generally, red, green, and blue) color filters are provided on one substrate (color filter substrate, hereinafter referred to as a counter substrate) sandwiching a liquid crystal layer. In general, a color filter is formed by applying a mixture of an organic material and an organic coloring material such as a dye or a pigment and repeating patterning using a photolithography technique for each of the three-color filters. Note that before or after the formation of the color filter, a light-shielding film that separates each color, that is, a black matrix is formed by a similar method.

Further, a smooth layer of organic material (protective film: overcoat layer) covering the color filter to smooth the inner surface of the color filter substrate in order to equalize the gap between the opposing surfaces of the pair of substrates, ie, the cell gap. ) Is formed.

In a liquid crystal display device which is formed by bonding a color filter substrate on which a thin film of such an organic material is formed to another substrate (active matrix substrate, hereinafter referred to as an electrode substrate), a shock is applied. Bubbles were sometimes generated. However, the cause was unknown.

As a countermeasure against this, conventionally, Japanese Patent Application Laid-Open No. 8-234 has been disclosed.
As disclosed in Japanese Patent Publication No. 188, a method of baking a so-called empty cell in a state before injecting liquid crystal by bonding it to a color filter substrate or an active matrix substrate, mainly by a degassing treatment of adsorption gas represented by hydration water. It corresponded vaguely.

[0011]

Generally, in a liquid crystal display device using a counter substrate on which a color filter is formed, unlike the electrode substrate, most of the constituent elements of the substrate are organic materials. Since a decomposable gas is generated due to its own gas generation potential or damage due to external factors, it has been confirmed that the gas dissolves in the liquid crystal when stored or used at normal temperature and normal pressure.

When the gas thus dissolved in the liquid crystal reaches a saturated state, the liquid crystal display generally comprises a highly flexible substrate such as a counter substrate made of a thin glass substrate which is easily deformed by an external force. Due to the characteristics of the device, when an impact is applied to the display surface due to, for example, pressing with a finger or dropping, bubbles may be generated in the liquid crystal display device, resulting in display failure.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art. Various types of thin films, especially smooth layers, formed by storage for a long time or by application of an external force during use, are provided. An object of the present invention is to provide a liquid crystal display device having high reliability by preventing generation of bubbles from an organic material film.

[0014]

In order to achieve the above object, the present invention provides an alignment film having an organic thin film such as a smoothing layer and for aligning liquid crystal molecules constituting a liquid crystal on the innermost layer. The pair of substrates formed is opposed to each other with a predetermined gap, the periphery thereof is adhered with a sealant, and the temperature of the substrate of the liquid crystal display device in which liquid crystal is sealed in the gap is increased in a predetermined vacuum environment. A characteristic feature is that the obtained amount of detected carbon dioxide is confirmed to be a predetermined value.

[0015] A typical configuration of the present invention is as follows:
As described in (3). That is, (1) a liquid crystal is sealed in a gap between a pair of substrates having a thin film of an organic material formed on an inner surface thereof, and the periphery thereof is adhered with a sealing material. The degree of vacuum is 1 × 10 ⁻⁶ Pa. The temperature-desorption gas generator described below was used to raise the temperature at 10 ° C / min and measure at 1 ° C intervals. The integrated amount of the detected ionic strength of carbon dioxide from room temperature to 250 ° C was 70,000 or less. A liquid crystal display device was constructed using a thin film of the above organic material.

By using the above substrate, generation of bubbles from the organic material film is prevented, and a high quality and highly reliable liquid crystal display device can be obtained.

(2) At least a color filter layer, a smoothing layer covering the color filter layer and one substrate having an upper alignment film formed on the innermost surface, and the other substrate having a lower alignment film formed on at least the innermost surface. A liquid crystal display device in which an alignment film and a lower alignment film are opposed to each other at a predetermined gap, a liquid crystal is sealed in the gap, and the periphery is bonded with a sealing material. The degree is 1 × 10 ⁻⁶ Pa.
The temperature-desorption gas generator described below was used to raise the temperature at 10 ° C / min and measure at 1 ° C intervals. The integrated amount of the detected ionic strength of carbon dioxide from room temperature to 250 ° C was 70,000 or less. It comprised using the said certain smooth layer.

According to the liquid crystal display device using the above substrate,
In particular, generation of bubbles from a smooth layer formed over the color filter, that is, a so-called overcoat layer, is prevented, and a high-quality and highly reliable liquid crystal display device can be obtained.

(3) The hardness of the smooth layer in the above (1) or (2) is 3H or more.

With the above-described configuration, generation of gas (bubbles) inside the liquid crystal display device during storage or use is suppressed, and a high quality and highly reliable liquid crystal display device can be obtained.

It should be noted that the present invention is not limited to the above configuration, and various changes can be made within the technical idea of the present invention.

[0022]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view of a principal part for explaining the structure of one embodiment of a liquid crystal display device according to the present invention. Where SUB
1 is an electrode substrate, and SUB2 is a counter substrate. Electrode substrate S
UB1 is formed with a normal thin film transistor TFT. That is, the thin film transistor TFT has the gate electrode GT, the drain electrode SD1, and the source electrode SD2 with the amorphous silicon layer AS interposed therebetween, and the electrode substrate SUB
1 has an insulating film P covering the thin film transistor TFT.
An SV is formed, a pixel electrode ITO1 having one end connected to the source electrode SD2 is formed thereon, and a lower alignment film ORI1 is further formed thereon.

On the other hand, on the inner surface of the counter substrate SUB2, a lower filter FIL (here, only the green filter FIL (G) is shown) partitioned by a black matrix BM is formed, and a smooth layer (protection layer) is formed thereon. Film) OC is formed. A common electrode ITO2 is formed to cover the smooth layer OC, and an upper alignment film ORI2 is formed on the uppermost layer.

The smoothing layer OC is made of an organic resin having a pencil hardness of H (hardness according to Japanese Industrial Standard JIS K5400, paragraph 6.14) or more. On the counter substrate SUB2 side, the amount of gas generation is kept low by controlling the degree of hardening of the smooth layer OC. The pair of substrates SUB1 and SUB2 are bonded together with a spacer SP interposed therebetween at a predetermined gap, and a liquid crystal LC is sealed in the gap.

Incidentally, a polarizing plate PO is provided on each surface of the pair of substrates.
L1 and POL2 are each laminated.

The generated gas potential on the side of the counter substrate SUB1 having such a configuration is investigated as follows. The analyzer used here is “EMD-WA1000” (trade name), a high-precision temperature rising / leaving gas analyzer manufactured by Denshi Kagaku Co., Ltd.

FIG. 2 is a schematic diagram illustrating the configuration of a temperature rising desorption gas analyzer used in the present invention. This apparatus is roughly composed of a sample introduction chamber RS, a heating chamber CH, and a mass spectrometer MS. SPL is a sample, that is, a measurement sample, TM is a thermocouple for measuring a sample temperature, ROD is a quartz rod holding the sample, IR is an infrared ray introduction chamber, TC is a temperature controller for controlling the temperature in a heating chamber, and TMP.
Is a turbo molecular pump for making the inside of the heating chamber CH and the mass spectrometry chamber MS a predetermined high vacuum degree, RP is a rotary pump for evacuating the inside of the heating chamber CH, VG is a vacuum gauge, CTRL is an apparatus control controller, and PC is 2 shows a control computer.

The sample (here, the counter substrate SUB2 on which at least the smooth layer OC is formed) introduced into the heating chamber CH is subjected to infrared heating under a high vacuum condition, and the gas released by the heating is subjected to a mass as needed. Analyze with the analyzer MS. The measurement conditions of the mass spectrometer MS are as follows. Assuming that the emission current is 50 μA and the voltage of the secondary electron multiplier is 2 kV, the mass for measuring four channels of m / e = 2, 18, 28, 44 at an interval of about 2 seconds. It was measured by the fragment method. Other conditions of the mass spectrometer MS were adjusted according to the instructions attached to the apparatus. Note that m / e = 2 is hydrogen (H ₂ ), 18 is water (H ₂ O), and 28 is carbon monoxide (C
O) and 44 are the respective masses of carbon dioxide (CO ₂ ). The counter substrate SUB2 of the sample was cut into a size of 10 mm × 10 mm, and the quartz rod ROD in the chamber CH was cut.
Placed above.

In the mass spectrometry, 1 ×
10 ^-6 Pa. After reaching the following degree of vacuum, about 10 ° C /
The temperature was raised from room temperature to 250 ° C. at a rate of
e = 28, 44, other ion peaks and heating chamber C
The internal pressure of H was measured.

For the above ion peak, a pyrogram (substrate temperature-ion peak spectrum) was taken.

FIG. 3 is a graph showing the temperature of the desorption gas (C
Is an illustration of pyrograms of O _2). In the figure, the horizontal axis is the temperature in the heating chamber, and the vertical axis is m / e = 44 (CO ₂ ).
The detection intensity (count value) of Example 1
2 and Comparative Example 1 are shown. What is indicated by B is the background.

Even if the measured temperature rises to some extent, there is almost no change and it is almost constant equal to the background. on the other hand,
In Examples 1 and 2 and Comparative Example, the temperature is almost equal to the background up to 150 ° C., but the pyrogram increases as the temperature further increases. In the present invention, the difference between the detected ion peak intensities in the range from room temperature to 250 ° C. is integrated to obtain a relative value as a measure of the gas released from the counter substrate. This integrated value exceeded 100,000 in the comparative example. As a result, gas was generated from the color filter substrate, and the display quality was degraded.

According to the method described above, the amount of released gas was measured, and the integrated amount and the degree of gas generation were verified. As a result, if the integrated amount was 70000 counts or less, a liquid crystal display device in which no gas was generated even in the conventional configuration was obtained. Was found to be possible.

In order to achieve this integrated amount, the smooth layer O
It is important to increase the hardness of C or to cure it under the firing conditions that provide the highest hardness. It is also effective to perform baking at atmospheric pressure after forming the ITO film.

Next, a method for manufacturing such a liquid crystal display device will be described. First, as a counter substrate (color filter substrate) used for a liquid crystal display device, a photosensitive black resin resist is applied on a glass substrate having a thickness of 0.7 mm or 1.1 mm, exposed, developed, and baked. Thereby, a black matrix BM is formed. Next, the photosensitive red,
The same steps as described above are repeated using green and blue resin resists to form a red colored layer FIL (R), a green colored layer FIL (G), and a blue colored layer FIL (B).

Next, a resin is applied and baked so that the pencil hardness becomes H or more to form a smooth layer (protective film) OC, and a transparent electrode ITO is formed thereon by a low-temperature sputtering method.
This is a common electrode. Finally, an upper alignment film ORI2 is applied and rubbed to give liquid crystal alignment controllability.

On the other hand, the electrode substrate (active matrix substrate) side is manufactured by the same method as the process for forming a general thin film transistor TFT. That is, the thickness 0.7
The film formation and patterning are repeated on a glass substrate of 0.1 mm or 1.1 mm to form a thin film transistor TFT made of amorphous silicon AS and a storage capacitor Cstg (FIG. 6).
, A drain electrode SD1, a source electrode SD2, a gate electrode GT, a pixel electrode ITO1, and a drain line.
Various wiring groups such as gate lines and electrode groups are formed. After that, the insulating film PSV is covered so as to cover them, and the lower alignment film ORI1 is applied thereon. The upper and lower alignment films are applied by offset printing, baked, and rubbed (rubbed) in a predetermined direction to provide liquid crystal alignment control ability.

An epoxy adhesive mixed with a gap regulating material such as fiber is screen-printed on one edge of the counter substrate and the electrode substrate thus formed, and plastic beads are spray-sprayed as spacers. Paste and glue. Spacer spray density is 150
Pieces / mm ² .

An opening for injecting liquid crystal is formed in a part of the sealing material, and after curing, liquid crystal is filled from the opening by a vacuum injection method, and the opening is sealed with an epoxy-based adhesive. .

The liquid crystal display devices of the examples and the comparative examples, which will be described later, prepared as described above, were manufactured at 50 ° C.
After keeping it warm for a day, the following impact bubble test was performed.

FIG. 4 is a schematic view of a test apparatus for explaining the impact bubble test method. This apparatus is provided with a static elimination sheet RB on a Lauan material WD, and a liquid crystal display device LCD mounted thereon. Push rod A with a hard ball attached to the tip
The RM is lowered to press the liquid crystal display device with a hard ball.

According to this test method, a hard sphere having a diameter of about 3 cm and a weight of 50 g was pressed at 2 kg × 3 seconds under normal temperature and normal pressure to form a bubble nucleus of about 1 mm in the liquid crystal display device, and a test for measuring the extinction time was performed. Was.

FIG. 5 is an explanatory diagram of the correlation between the shock bubble test and the integrated value of the heated desorption gas. As a result of the impact bubble test method described with reference to FIG. 4, in the examples of the present invention described below, it was confirmed that the bubble nuclei disappeared after being left for 15 minutes.
In the comparative example, the bubble nuclei did not disappear even after being left for one week.

Next, specific examples and comparative examples of the liquid crystal display device according to the present invention will be described.

Example 1 A smooth film OC having a pencil hardness of 4H was prepared at a firing temperature of 220 ° C. using “V259PA” (trade name) manufactured by Shinnichika as the smooth film OC material. When the integrated value of the amount of generated gas after forming the common electrode ITO2 thereon was measured by the method described in FIG. 2, the integrated value of the carbon dioxide ion intensity was 200 at the maximum.
It was 00-40000, and was 35,000 on average.

After keeping the liquid crystal display device manufactured using this counter substrate at 50 ° C. for 30 days, the disappearance time of the bubble nuclei was measured by the impact bubble test shown in FIG. 4, and the bubble nuclei disappeared when left for 15 minutes. did.

Example 2 As a smooth film OC material, "V259PA" manufactured by Shinnichika was used, and the firing temperature was 240 ° C.
As C, a smooth film OC having a pencil hardness of 3H was prepared. When the integrated value of the gas generation amount after forming the common electrode ITO2 thereon was measured by the method described with reference to FIG. 2, the integrated value of the carbon dioxide ion intensity was 70,000 at the maximum. The liquid crystal display device manufactured using this counter substrate is 50
After maintaining the temperature at 30 ° C. for 30 days, the disappearance time of the bubble nuclei was measured by the impact bubble test in FIG. 4, and the bubble nuclei disappeared when left for 5 minutes.

"Comparative Example" As a smooth film OC material, "V259PA" manufactured by Shinnichika was used, and the firing temperature was 200 ° C.
As a result, a smooth film OC having a pencil hardness of 2H was prepared. When the integrated value of the amount of generated gas after forming the common electrode ITO2 thereon was measured by the same means as above, the integrated value of the carbon dioxide ion intensity exceeded 100000 at least. The liquid crystal display device manufactured using this counter substrate is 50
After maintaining the temperature at 30 ° C. for 30 days, the extinction time of the bubble nuclei was measured by the impact bubble test of FIG. 4, and as shown in FIG.
Even if left for one week, the bubble nuclei did not disappear, but rather grew.

Thus, as described in each embodiment of the present invention, if the integrated amount of the carbon dioxide ion intensity from room temperature to 250 ° C. is 70,000 or less, no bubbles are generated, and the display caused by the bubbles is not generated. Defects are suppressed.

Next, a specific configuration example of a liquid crystal display device to which the present invention is applied will be described in detail with reference to FIGS.

FIG. 6 is a plan view for explaining the structure of one pixel of a liquid crystal display device to which the present invention is applied and the periphery thereof. Each pixel has two adjacent gate lines GL (gate line G in the figure).
L (g2)) and two adjacent drain lines DL (data lines DL (d2, d3)) (in a region surrounded by four signal lines).

Each pixel is a switching element thin film transistor TFT (two thin film transistors TFT1 and T1).
FT2), a transparent pixel electrode ITO1, and an additional capacitance (holding capacitance element) Cadd. The gate lines GL extend in the x direction (column direction), and a plurality of gate lines GL are arranged in the y direction (row direction). The drain lines DL extend in the y direction, and a plurality of drain lines DL are arranged in the x direction.

The gate electrode GL (g2) is connected to the gate line GL.
Is connected, and a drain electrode (SD2) is connected to the drain line DL.
(D2, d3) are connected. Also, ITO1 (d1)
Denotes a pixel electrode, which is connected to the source electrode (SD1 (d2, d3)) of the thin film transistor TFT.
Represents an amorphous Si layer, and d1, d2, d3, and g2 represent conductor layers for forming each electrode or wiring.

In the figure, the color filter FIL and the black matrix BM are formed on a color filter substrate, and only the arrangement positions are shown in this figure.

FIG. 7 is a circuit configuration diagram of an equivalent circuit of a liquid crystal panel constituting a liquid crystal display device and a drive circuit and the like arranged on the outer periphery thereof. In this configuration, a thin film transistor (TF
The drain drive circuit unit 103 is arranged only below the T) type liquid crystal panel PNL (TFT-LCD), and is 800 × 6
The gate drive circuit unit 104 and the controller unit 10
1. The power supply unit 102 is provided.

The thin film transistor TFT is arranged in an intersection region between two adjacent drain lines DL and two adjacent gate lines GL. A drain electrode and a gate electrode of the thin film transistor TFT are connected to a drain line DL and a gate line GL, respectively.

The source electrode of the thin film transistor TFT is connected to the pixel electrode, and the pixel electrode and the common electrode (common electrode)
, A liquid crystal capacitor (C _LC ) is equivalently connected to the source electrode of the thin film transistor TFT. The thin film transistor TFT becomes conductive when a positive bias voltage is applied to the gate electrode, and becomes nonconductive when a negative bias voltage is applied. A storage capacitor Cadd is connected between the source electrode of the thin film transistor TFT and the previous gate signal line.

It should be understood that the source electrode and the drain electrode are originally determined by the bias polarity between them, and in this liquid crystal display device, the polarities are inverted during the operation, and therefore, it should be understood that the source electrode and the drain electrode are switched during the operation.

FIG. 8 is an exploded perspective view showing each component of the liquid crystal display device modularized together with lighting means and the like.
SHD is a metal shield case (upper frame), WD is its display window, PNL is a liquid crystal panel, SPS is a light diffusion plate,
GLB is a light guide, RFS is a reflector, BL is a backlight, MCA is a lower case (lower frame), and each member is stacked in a vertical arrangement as shown in the figure to form a so-called liquid crystal display module MDL. Assembled.

The whole liquid crystal display module MDL is fixed by nails provided on the upper frame SHD and hooks formed on the lower frame MCA.

Drive circuit boards (gate-side circuit board, drain-side circuit board) PCB1, PCB1,
PCB2, interface circuit board PCB3 is tape carrier pad TCP1, TCP2 or Joiner J
The liquid crystal panel PML and the circuit board are connected to each other by N1, JN2, and JN3.

The lower frame MCA has a light diffusion sheet S constituting a backlight BL as an illuminating means in its opening MO.
It is configured to house the PS, the light guide GLB, and the reflector RFS. Note that a linear lamp (fluorescent tube) LP and a reflection sheet LS are arranged on the side surface of the light guide GLB. A lamp cable LPC held by a rubber bush GB is drawn out from the end of the linear lamp LP, and is connected to an inverter power supply (not shown).

The light emitted from the linear lamp LP is emitted toward the liquid crystal display panel PNL as uniform illumination light on the display surface by the light guide GLB, the reflection plate RFS, and the light diffusion plate SPS.

Backlight BL and liquid crystal display panel PNL
The prism sheet PRS placed between the two is for adjusting the path of the illumination light, and is laminated via the light shielding spacer ILS.

FIG. 9 is a perspective view of a notebook computer for explaining a mounting example of the liquid crystal display device according to the present invention. The notebook computer (portable personal computer) includes a keyboard unit (main body unit) and a display unit connected to the keyboard unit by a hinge. The keyboard unit accommodates a keyboard and a signal generation function unit such as a host (host computer) and a CPU, and the display unit is mounted with the liquid crystal display module described with reference to FIG. Is exposed. Then, around the liquid crystal panel PNL, drive circuit boards FPC1 and FPC2, a PCB on which the control chip TCON is mounted, an inverter power supply board IV serving as a backlight power supply, and the like are mounted.

It should be noted that the present invention is not limited to the above embodiment, and various changes can be made without departing from the technical idea of the present invention.

[0068]

As described above, according to the present invention,
Prevents the generation of bubbles from various thin films formed on the inner surface of the liquid crystal display panel, especially organic material films such as a smooth layer (overcoat layer), even when stored for a long time or when an external force is applied during use. Thus, a highly reliable liquid crystal display device free from display defects can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a principal part explaining a configuration of an embodiment of a liquid crystal display device according to the present invention.

FIG. 2 is a schematic diagram illustrating the configuration of a thermal desorption gas analyzer used in the present invention.

FIG. 3 is an explanatory diagram of a pyrogram of a heated desorption gas (CO ₂ ) implemented in the present invention.

FIG. 4 is a schematic view of a test apparatus for explaining an impact bubble test method.

FIG. 5 is an explanatory diagram of a correlation between an impact bubble test and an integrated value of a heated desorption gas.

FIG. 6 is a plan view illustrating a configuration of one pixel of a liquid crystal display device to which the present invention is applied and the periphery thereof.

FIG. 7 is a circuit configuration diagram of an equivalent circuit of a liquid crystal panel constituting a liquid crystal display device and a driving circuit and the like arranged on an outer peripheral portion thereof.

FIG. 8 is an exploded perspective view showing each component of the liquid crystal display device modularized together with lighting means and the like.

FIG. 9 is a perspective view of a notebook computer for explaining a mounting example of a liquid crystal display device according to the present invention.

[Explanation of symbols]

SUB1 Electrode substrate SUB2 Counter substrate TFT Thin film transistor AS Amorphous silicon layer GT Gate electrode SD1 Drain electrode SD2 Source electrode PSV Insulating film ITO1 Pixel electrode ORI1 Lower alignment film BM Black matrix FIL (R), FIL (G) Red and green color filters OC Smooth layer (protective film: overcoat layer) ITO2 common electrode ORI2 Top alignment film.

Continued on the front page (72) Inventor Teruo Kitamura 3300 Hayano, Mobara-shi, Chiba Pref.Electronic Devices Division, Hitachi, Ltd. (72) Inventor Akira Ishii 3681-Hayano, Mobara-shi, Chiba Pref. Person Toshio Sato 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd. (72) Inventor Takumi Kuji 3300, Hayano, Mobara-shi, Chiba F-term in Hitachi, Ltd., Electronic Devices Division 2H088 FA02 FA03 FA04 HA04 MA20 2H089 LA08 LA15 LA20 MA03X MA03Y NA09 NA19 NA25 NA41 NA58 QA16 TA05 2H091 FA02Y FA35Y FC10 GA03 GA06 GA08 GA09 GA13 GA16 LA16 LA30

Claims (3)

[Claims] 1. A liquid crystal display device comprising a pair of substrates each having a thin film of an organic material formed on the inner surface thereof, in which liquid crystal is sealed in a gap between the substrates and a peripheral edge of which is bonded with a sealant. The ultimate vacuum degree of the formed substrate is 1
× 10 ^-6 Pa. 10 ° C with the following thermal desorption gas generator
/ Min, and the use of a thin film of the organic material, wherein the integrated amount of the detected ionic strength of carbon dioxide obtained by measuring every 1 ° C from room temperature to 250 ° C is 70,000 or less is 70,000 or less. Characteristic liquid crystal display device. 2. The upper alignment of at least one substrate having a color filter layer, a smooth layer covering the color filter layer and an upper alignment film formed on the innermost surface, and the other substrate having a lower alignment film formed on at least the innermost surface. A liquid crystal display device in which a film and a lower alignment film are opposed to each other with a predetermined gap, and a liquid crystal is sealed in the gap and a peripheral edge is bonded with a sealing material. Is 1 ×
10 ^-6 Pa. 10 ° C /
And the integrated amount from room temperature to 250 ° C. of the detected ionic strength of carbon dioxide obtained by measuring the temperature every 1 ° C. every minute is 70,000 or less. Liquid crystal display. 3. The liquid crystal display device according to claim 2, wherein the hardness of the smooth layer is 3H or more.