KR20110086497A - Apparatus for manufacturing liquid crystal panel - Google Patents

Abstract

PURPOSE: A manufacturing device of liquid crystal panel is provided not to increase the temperature of a liquid crystal panel among light irradiation form polymerizing the ultraviolet reaction material. CONSTITUTION: A manufacturing device includes a supporting unit, and an optical irradiating unit(1). The supporting unit supports a liquid crystal panel(3) of a MVA method which is mounted inside a liquid crystal including an optical reaction material. The optical irradiating unit irradiates the light from a lamp about the liquid crystal panel supported by the supporting unit.

Description

Manufacturing apparatus of liquid crystal panel {APPARATUS FOR MANUFACTURING LIQUID CRYSTAL PANEL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal panel of a multi-domain vertical alignment (MVA) method. In particular, polymerization is carried out in response to a liquid crystal having an alignment property oriented by voltage application between two glass substrates and ultraviolet rays. The manufacturing apparatus of the liquid crystal panel which seals the material which mixed the photoreactive substance to generate | occur | produce, and forms an alignment film on a glass plate by irradiating an ultraviolet-ray to this liquid crystal panel and polymerizing an ultraviolet-ray reactive material.

The structural example of a liquid crystal panel is shown in FIG. The liquid crystal panel 50 is a structure which enclosed the liquid crystal 58 between two light transmissive substrates (1st glass substrate 51 and 2nd glass substrate 52), and has a 1st glass substrate ( A large number of active elements (e.g., thin film transistor: TFT 53) and a liquid crystal drive electrode 54 (transparent electrode ITO) are formed on 51, and an alignment film 56 is formed thereon. . On the second glass substrate 52, a color filter 57, an alignment film 56, and a transparent electrode (ITO) 55 are formed. The liquid crystal 58 is sealed between the alignment films of the two glass substrates 51 and 52, and the circumference is sealed by the sealing agent 59.

In the liquid crystal panel of such a structure, the alignment film 56 is for controlling the liquid crystal alignment for orientating the liquid crystal by applying a voltage between the electrodes 54 and 55. Conventionally, the control of the alignment film has been performed by rubbing, but recently, a new orientation control technique has been tried.

This is because orientation between the first glass substrate 51 provided with the TFT element 53 and the second glass substrate 52 opposing the first glass substrate 51 is oriented by voltage application. The branch is filled with a liquid crystal 58 and a material mixed with a photoreactive substance which reacts with ultraviolet rays to cause polymerization (ultraviolet reaction material, sometimes simply referred to as a monomer hereinafter). Irradiation polymerizes the ultraviolet reaction material (monomer), and fixes the pretilt angle to the liquid crystal by fixing the orientation of the liquid crystal (ie, approximately 1 molecular layer of the surface layer) in contact with the glass substrates 51 and 52 through the alignment film 56 or the like. It gives it (for example, patent document 1).

According to this method, since the projection which has the slope required conventionally to give a pretilt angle becomes unnecessary, the manufacturing process of a liquid crystal panel can be simplified. Therefore, the manufacturing cost and manufacturing time of the liquid crystal panel can be reduced, and the shadow caused by the projections is eliminated, so that the aperture ratio is improved, which leads to the reduction of the power consumption of the backlight.

In the manufacturing technology of the liquid crystal panel which performs this new orientation control, about the processing method which irradiates an ultraviolet-ray with respect to the material (Hereinafter, it may be called liquid crystal containing an ultraviolet-ray reacting material) which mixed a liquid crystal and an ultraviolet-ray reactive material, The proposal is made.

In "Liquid crystal display element device and its manufacturing method" described in Patent Literature 2, ultraviolet irradiation under the first condition and ultraviolet irradiation under the second condition in which the polymerization rate is larger than the ultraviolet irradiation under the first condition are performed in this order. The manufacturing method (refer to description of paragraph 0012 etc.) of the liquid crystal display device performed in combination with the is proposed. Specifically, ultraviolet irradiation is performed under conditions in which the irradiance and the integrated intensity of the second condition are larger than the first condition.

In this way, in the ultraviolet irradiation under the first condition, since the polymerization is relatively slow, the occurrence of alignment abnormality can be suppressed, and thereafter, even if the polymerization rate is increased, there is no problem, and a liquid crystal layer having no or abnormality in alignment can be obtained. . In the ultraviolet irradiation under the second condition, it is described that it is preferable to increase the ratio of the low wavelength component near 310 nm (see description of paragraph 0037 and the like).

In the "liquid crystal display device device and its manufacturing method" described in Patent Literature 3, "in order not to deteriorate a liquid crystal, it turned out that it was better to irradiate the ultraviolet-ray which cut | disconnected short wavelength region of less than 310 nm using the filter." However, if the intensity at wavelength 310 nm is completely zero, it is difficult to obtain the desired liquid crystal alignment. For this reason, it is preferable to use an included light source for an intensity of about 0.02 to 0.05 mW / cm 2 at a wavelength of 310 nm '' (see paragraph 0019 and the like).

In the "liquid crystal display device device and its manufacturing method" described in Patent Document 4, although ultraviolet rays having a short wavelength are advantageous for obtaining vertical alignment of the liquid crystal in a short time, it is easy to promote deterioration of liquid crystal molecules and the like, On the contrary, although the ultraviolet side hardly promotes deterioration of liquid crystal molecules and the like, it takes a long time to obtain the vertical alignment property of the liquid crystal (see paragraph 0031 and the like), and the wavelength range of the ultraviolet ray to be irradiated is shown. However, patent document 4 does not mention about the temperature rise of a color filter.

<Patent Document 1> Japanese Patent Laid-Open No. 2003-177408 <Patent Document 2> Japanese Patent Application Laid-Open No. 2005-181582 <Patent Document 3> Japanese Patent Application Laid-Open No. 2005-338613 <Patent Document 4> Japanese Patent Application Laid-Open No. 2006-58755

As described above, several proposals have been made regarding a treatment method of irradiating ultraviolet light emitted from an ultraviolet light source with respect to a material mixed with a liquid crystal and an ultraviolet light reaction material. I also gained knowledge.

In the liquid crystal panel using the new novel orientation control as described above, an ultraviolet-ray reacting material that reacts with ultraviolet light to cause polymerization is mixed, and the ultraviolet-ray reacting material polymerizes by ultraviolet irradiation.

When irradiating ultraviolet rays to the liquid crystal panel, as shown in FIG. 12, the first glass substrate 51 side opposite to the second glass substrate 52 on which the color filter 57 is formed is shown. From the ultraviolet rays. Therefore, if the light emitted from the ultraviolet light source contains light of a wavelength belonging to the wavelength range absorbed by the color filter 57, the color filter 57 is heated.

When the color filter 57 is heated, heat is transferred from the heated color filter 57 to the liquid crystal 58 or ultraviolet-ray reactive material enclosed between the glass substrates 51 and 52, and they are heated. Thereby, the temperature distribution of an ultraviolet-ray reactive material arises, the polymerization reaction (hardening reaction) rate distribution of the said ultraviolet-ray reactive material arises, and an irregular change arises in a polymerization rate (hardening rate). As a result, an irregular change occurs in the pretilt angle and a problem of liquid crystal display nonuniformity occurs. In addition, when the temperature of the liquid crystal 58 to be heated becomes a high temperature, the deterioration of the liquid crystal is also concerned.

Therefore, during the ultraviolet irradiation emitted from the ultraviolet light source, it is preferable that the temperature distribution of the whole liquid crystal panel is uniform in order to reduce the irregular change of the pretilt angle. At this time, it is preferable that the temperature of liquid crystal does not become high temperature either. For this reason, during ultraviolet irradiation, the stage in which a liquid crystal panel is placed is cooled (for example, water cooling), and it controls so that the whole liquid crystal panel may become uniform temperature distribution.

However, the liquid crystal panel has been enlarged in recent years (for example, from 2 m x 2 m or more), and the stage which mounts a liquid crystal panel is also enlarged in addition. When the temperature of a liquid crystal panel rises by heating, a large size | cooler is needed in order to lower the temperature, and the cost of an apparatus becomes high. In addition, as the temperature increases, it becomes difficult to control the temperature distribution of the large area as described above to be uniform.

Moreover, when temperature rises during irradiation, the light transmissive substrate (1st glass substrate 51) by the side to which light is irradiated may expand | stretch by thermal expansion, and a liquid crystal panel may deform | transform, and may cause a defect.

As described above, in the production of a liquid crystal panel using the above-described novel orientation control in which an ultraviolet reaction material is mixed with a liquid crystal and irradiated with ultraviolet rays, a polymerization reaction is generated. The problem of heat generation by comparison has not been discussed so far in the wavelength range.

This invention is made | formed in view of the said situation, The objective of this invention is providing the manufacturing apparatus of the liquid crystal panel in which the temperature of a liquid crystal panel did not rise as much as possible during light irradiation for superposing | polymerizing (curing) an ultraviolet-ray reactive material. will be.

The inventors discovered the following as a result of earnestly examining.

First, the absorbance with respect to the wavelength of light was measured about the ultraviolet-ray reaction material (monomer) currently mixed with the liquid crystal currently used. The graph of the absorbance of the ultraviolet-responsive material with respect to the wavelength of light which is the result in FIG. 1 is shown. In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents transmittance (%).

As shown in the figure, light is absorbed particularly in the region of the wavelength of 370 nm or less, that is, the ultraviolet reaction material causes a polymerization reaction. In reality, however, it was found that the dominant contribution to the polymerization reaction is light with a wavelength of 360 nm or less, and the contribution to the polymerization reaction of light with a wavelength longer than the wavelength of 360 nm is remarkably small.

Here, the spectral characteristics (SHOTT company) of a color filter are shown in FIG. In the figure, the horizontal axis represents wavelength and the vertical axis represents transmittance.

As shown in the figure, the red color of the color filter (R in FIG. 2) absorbs and heats without transmitting light having a wavelength of about 570 nm or less. Green (G of the same figure) absorbs and heats without transmitting light of wavelength about 450 nm or less. In addition, the blue color (B of the same figure) of a color filter absorbs and heats it, without transmitting the light of wavelength about 330 nm or less. Thus, light having a wavelength of about 570 nm or less heats the color filter.

Therefore, in order to minimize the heating of the liquid crystal panel, the lamp emits light in the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel, and the contribution of the ultraviolet reaction material to the polymerization reaction is small, and the color filter It is conceivable to carry out the ultraviolet irradiation treatment of the liquid crystal panel using an ultraviolet light source as small as possible to emit light in the wavelength region which is absorbed in and heats the color filter.

Specifically, the integrated emission illuminance of the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel is a, and the integrated emission illuminance of the wavelength region which is the absorption wavelength of the color filter and does not contribute to the reaction of the photoreactive substance is b. In this case, it is preferable that the accumulated irradiance of the lamp is a> b.

That is, in the wavelength range absorbed by the color filter, as shown in Fig. 2, blue absorbs light having a wavelength of about 330 nm or less, green absorbs light of 460 nm or less, and red has 570 nm or less. Absorbs light, thereby heating the color filter.

In addition, the wavelength substantially effective for hardening of an ultraviolet-ray reactive material is 360 nm or less, and the wavelength which damages a liquid crystal is substantially 310 nm or less. In addition, when 310 nm light is 0, complete hardening is not obtained. On the other hand, when the light of 300 nm or less is contained, since damage to liquid crystal becomes large, it is preferable not to contain light of 300 nm or less.

As mentioned above, since the wavelength of 360 nm-570 nm not only contributes to hardening of an ultraviolet-ray reactive material, but is absorbed by a color filter, the light of this wavelength range produces only the heating effect of a color filter as a result.

When the color filter is heated by absorption by the color filter, heat is transferred to the glass substrate and the liquid crystal-ultraviolet reaction material, and these are heated.

The temperature distribution of an ultraviolet-ray reactive material arises, the hardening reaction rate distribution of an ultraviolet-ray reactive material arises, and an irregular change in a hardening rate arises. As a result, an irregular change occurs in the pretilt angle, resulting in a problem of liquid crystal display nonuniformity.

As described above, when the ultraviolet irradiation treatment of the liquid crystal panel is performed using the light emitted from the ultraviolet light source, the integrated emission illuminance a in the wavelength region of 310 nm to 360 nm is> 360 nm to 570 nm. It turned out that it is preferable that it is set to the integrated irradiance b] of the wavelength range of.

In other words, such a lamp is used by using a lamp that emits light in a wavelength region of [integrated emission illuminance a in a wavelength region of 310 nm to 360 nm]> [integrated emission illuminance b in a wavelength region of 360 nm to 570 nm]. By irradiating light to the liquid crystal panel from the provided light irradiation unit and reacting the photoreactive substance in the liquid crystal panel, the temperature rise of the color filter is suppressed, the temperature rise of the liquid crystal panel is suppressed to a minimum, and irregular variation in the pretilt angle is achieved. It is possible to effectively cure the ultraviolet reaction material while suppressing the occurrence.

As the lamp which emits such light, for example, the rare gas fluorescent lamp described in Japanese Patent Application No. 2009-51624 can be used.

The present inventors investigated which lamp can be used as a lamp which can irradiate the above light. As a result, it was found that it is preferable to use a rare gas fluorescent lamp as described later. In addition, the rare gas fluorescent lamp can change the wavelength range to emit.

Here, for three kinds of rare gas fluorescent lamps and metal halide lamps having different wavelength ranges, as described later, irradiation time required for curing the ultraviolet-reactive material (monomer) for imparting a pretilt angle to the liquid crystal, The rise of the temperature of the glass substrate when irradiance (mW / cm 2), the irradiation amount (mJ / cm 2), and the light from these lamps is irradiated to the glass substrate used for the liquid crystal panel with the irradiation time required for curing of the monomer. Investigated.

As a result, when the metal halide lamp was used, the temperature of the substrate rose to about 30 ° C. without air cooling. When using a rare gas fluorescent lamp, the temperature rise of the substrate could be suppressed to 8 ° C. or lower without air cooling.

In addition, the irradiation amount of the lamp with the largest irradiation amount in [the wavelength region of 360 nm-570 nm] at this time is 3333 (mJ / cm <2>), and when irradiation amount is 3500 (mJ / cm <2>) or less, the temperature rise of a glass substrate will be suppressed. It is thought that it can suppress below a desired value.

That is, when the light irradiation part of the manufacturing apparatus of a liquid crystal panel is comprised using the said rare gas fluorescent lamp, and the irradiation amount of the wavelength range of 360 nm-570 nm shall be 3500 (mJ / cm <2>) or less, the temperature rise of a color filter will be suppressed. The temperature rise of the liquid crystal panel can be suppressed to a minimum, and the occurrence of irregular changes in the pretilt angle can be suppressed.

Based on the above, this invention solves the said subject as follows.

(1) A support unit for supporting a liquid crystal panel of an MVA system in which a liquid crystal containing a photoreactive substance is enclosed with a color filter therein; and a light irradiation unit for irradiating light from a lamp to the liquid crystal panel supported by the support unit. And irradiating the light from the light irradiating portion with respect to the liquid crystal panel supported by the supporting portion to react the photoreactive material in the liquid crystal panel while applying a voltage to the liquid crystal panel to form an alignment portion in the liquid crystal panel. In the manufacturing apparatus of a liquid crystal panel, as a lamp of the said light irradiation part, in the emission spectrum of this lamp, the integrated emission intensity of the wavelength range which contributes to reaction of the photoreactive substance in a liquid crystal panel is a, and the absorption wavelength of a color filter is said When the integrated irradiance in the wavelength range that does not contribute to the reaction of the photoreactive substance is b, the integration of the lamp The illumination used for a> b the lamp.

(2) In the above (1), the integrated emission illuminance a is the integrated emission illuminance in the wavelength region of 310 nm to 360 nm, and the integrated emission illuminance b is the integrated emission illuminance in the wavelength region of 360 nm to 570 nm. .

(3) In (1) (2), a rare gas fluorescent lamp that does not substantially emit light having a wavelength of 300 nm or less is used as the lamp.

In the present invention, the integrated emission illuminance of the wavelength region of 310 nm to 360 nm, which is the wavelength region contributing to the reaction of the photoreactive substance, is defined as a, the wavelength range 360 of the absorption wavelength of the color filter and not contributing to the reaction of the photoreactive substance. When the integrated emission illuminance in the wavelength range of nm to 570 nm is b, the liquid crystal panel is irradiated using an ultraviolet light source of a> b. Therefore, the temperature rise of the color filter is suppressed and the temperature rise of the liquid crystal panel is minimized. Can be suppressed. For this reason, generation | occurrence | production of an irregular change in a pretilt angle can be suppressed, and an ultraviolet-ray reactive material can be hardened effectively.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the absorbance of the ultraviolet-ray reaction material with respect to the wavelength of light.
2 is a diagram illustrating spectral characteristics of a color filter.
It is a figure which shows the structural example of the manufacturing apparatus of the liquid crystal panel of this invention.
It is a figure which shows the structural example of a rare gas fluorescent lamp.
It is a figure which shows the other structural example of a rare gas fluorescent lamp.
Fig. 6 shows the spectral emission spectrum of the rare gas fluorescent lamp A.
7 shows the spectral emission spectrum of the rare gas fluorescent lamp B. FIG.
8 shows the spectral emission spectrum of the rare gas fluorescent lamp C. FIG.
Fig. 9 is a diagram showing the spectral emission spectra of the rare gas fluorescent lamps A, B and C superimposed.
10 is a diagram showing a spectral emission spectrum of a metal halide lamp.
Fig. 11 is a diagram showing the irradiance, the dose, and the temperature rise of the substrate of the rare gas fluorescent lamps A to C and the metal halide lamp.
It is a figure which shows the structural example of a liquid crystal panel.

The structural example of the manufacturing apparatus (ultraviolet irradiation apparatus) of the liquid crystal panel of this invention is shown in FIG.

The manufacturing apparatus (ultraviolet ray irradiation apparatus) of the liquid crystal panel of this invention is equipped with the light stage 1 and the work stage 2 which mounts the liquid crystal panel 3. The work stage 2 is provided with a mechanism 2a for applying a voltage to the mounted liquid crystal panel 3. As described in Patent Document 1, the liquid crystal panel 3 placed on the work stage 2 is irradiated with light from the light irradiation unit 1 while applying a voltage from the mechanism 2a for applying a voltage. .

As described above, the liquid crystal panel 3 is a structure in which a liquid crystal 3c containing an ultraviolet reaction material is enclosed between two light transmitting substrates (glass substrates) 3a and 3b, and the figure shows a conceptual diagram. As described above, a plurality of active elements TFT, a liquid crystal driving electrode, a color filter, and a transparent electrode ITO are formed on the glass plate, and the circumference is sealed with a sealing agent 3d.

The light irradiation unit 1 includes a light source (lamp) 1a and a mirror 1b, and as the light source (lamp) 1, [integrated emission illuminance in the wavelength region of 310 nm to 360 nm]> [360 nm] A rare gas fluorescent lamp emitting light having an integrated emission intensity in the wavelength region of ˜570 nm is used.

The light source 1a is fed from the power source 1c and turned on. The power source 1c and the mechanism 2a for applying the voltage are connected to the control unit 4, and the control unit 4 is turned on, off, irradiation time of the light source 1a, and voltage applied to the liquid crystal panel 8. Control the value, time, etc.

The liquid crystal panel 3 is mounted on the work stage 2 by a conveyance mechanism or the like not shown. The control part 4 applies a voltage from the mechanism 2a which applies a voltage, and irradiates light to the liquid crystal panel from the light irradiation part 1. And while controlling the voltage, time, etc. applied to a liquid crystal panel, while controlling the lighting time of the light source 1a, suppressing the temperature rise of a liquid crystal panel, hardening the ultraviolet-ray reaction material mixed with the liquid crystal, and The pretilt angle is imparted to the liquid crystal as if.

It is a figure which shows the structural example of the said rare gas fluorescent lamp. The rare gas fluorescent lamp has a tubular structure, and FIG. 4 shows a cross-sectional view cut in the plane including the tube axis. The rare gas fluorescent lamp 10 has a container (light emitting tube) 11 having a substantially double tube structure in which the inner tube 111 and the outer tube 112 are disposed substantially coaxially, and both ends 11A of the vessel 11 are provided. And 11B are sealed, a cylindrical discharge space S is formed therein. In the discharge space S, rare gases such as xenon, argon and krypton are sealed. The container 11 is made of quartz glass, and a low softening point glass layer 14 is provided on the inner circumferential surface, and a phosphor layer 15 is further provided on the inner circumferential surface of the low softening point glass layer 14. As this low-softened glass layer 14, hard glass, such as borosilicate glass and aluminosilicate glass, is used, for example. As the phosphor layer 15, for example, cerium-activated magnesium lanthanum (La-Mg-Al-O: Ce) phosphor is used. An inner electrode 12 is provided on the inner circumferential surface of the inner tube 111, and a mesh outer electrode 13 is provided on the outer circumferential surface of the outer tube 112. These electrodes 12 and 13 are arranged with the container 11 and the discharge space S interposed therebetween. The power supply device 16 is connected to the electrodes 12 and 13 via lead wires W11 and W12. When a high frequency voltage is applied from the power supply device 16, a discharge (so-called dielectric barrier discharge) interposed between the dielectrics 111 and 112 is formed between the electrodes 12 and 13, and in the case of xenon gas, a ruler having a wavelength of 172 nm External light occurs. The ultraviolet light obtained here is light for excitation of a fluorescent substance, and the ultraviolet light whose center wavelength is 340 nm vicinity is irradiated by irradiating a fluorescent substance layer.

The other structural example of a rare gas fluorescent lamp is shown in FIG. (A) shows sectional drawing cut | disconnected in the plane containing a tube axis | shaft, (b) shows sectional drawing of the AA line of (a). In FIG. 5, the lamp 20 has a pair of electrodes 22 and 23, and the electrodes 22 and 23 are provided on the outer circumferential surface of the container (light emitting tube) 21, and the outside of the electrodes 22 and 23. The protective film 24 is provided in this. The ultraviolet reflecting film 25 is provided in the inner surface on the opposite side with respect to the light emission direction side of the inner peripheral surface of the container 21 (refer FIG. 5 (b)), and the low softening point glass layer 26 is provided in the inner periphery. The phosphor layer 27 is provided on the inner peripheral surface of the softening point glass layer 26. The other structure is the same as that shown in FIG. 4, and the same applies to the gas enclosed in the discharge space S in the container 21 and the phosphor used for the phosphor layer 25. When a high frequency voltage is applied to the electrodes 22 and 23, a dielectric barrier discharge is formed between the electrodes 22 and 23, and ultraviolet light is generated as described above. As a result, the phosphor is excited, and ultraviolet light with a central wavelength of about 340 nm is generated from the phosphor layer, and the light is reflected by the ultraviolet reflecting film 25, and is radiated to the outside from an opening portion in which the ultraviolet reflecting film 25 is not provided. do.

6 to 8 show the spectral emission spectra of the rare gas fluorescent lamps used in the examples of the present invention. In addition, the horizontal axis represents wavelength (nm) and the vertical axis represents spectral irradiance (μW / cm 2 / nm).

As described above, the rare gas fluorescent lamp can change the wavelength range to emit by the combination of fluorescent materials, and FIGS. 6 to 8 show spectroscopy of three kinds of rare gas fluorescent lamps A, B, and C that differ in the wavelength range. The emission spectrum is shown. In addition, in FIG. 9, the spectral spectrum of three types of rare gas fluorescent lamps A, B, and C was superimposed, and is shown.

Here, in the rare gas fluorescent lamp A, a rare gas containing xenon as a main component is sealed in the discharge space S, and the phosphor layer 15 contains cerium-activated magnesium lanthanum (La-Mg-Al-O: Ce) phosphor (abbreviated LAM phosphor) is used.

In the rare gas fluorescent lamp B, a rare gas containing xenon as a main component is sealed in the discharge space S, and the cerium-activated barium aluminate magnesium (Ce-Mg-Ba-Al-) is contained in the phosphor layer 15. O) A phosphor (abbreviated CAM phosphor) is used.

On the other hand, in the rare gas fluorescent lamp C, a rare gas containing xenon as a main component is sealed in the discharge space S, and in the phosphor layer 15, cerium-activated yttrium phosphate (Y-P-O: Ce) phosphor (abbreviated as: YPC phosphor) is used.

In addition, as shown in FIG. 9, in the wavelength range of 310 nm to 360 nm, the wavelength ratio on the short wavelength side becomes [rare gas fluorescent lamp A]> [rare gas fluorescent lamp B]> [rare gas fluorescent lamp C]. have.

As shown in Fig. 6 to Fig. 8, the rare gas fluorescent lamp emits light of [integrated emission illuminance a in the wavelength region of 310 nm to 360 nm]> [integrated emission illuminance b of the wavelength region of 360 nm to 570 nm]. Radiate.

That is, this lamp has a small contribution to the polymerization reaction of the ultraviolet-reactive material, and also has a small emission ratio of light absorbed by the color filter and heating the color filter, so that the temperature rise of the color filter can be suppressed.

Therefore, the heating of the liquid crystal and the ultraviolet ray reaction material by the heat transfer from the color filter is also suppressed. For this reason, the temperature distribution of an ultraviolet-ray reaction material becomes substantially uniform, and the polymerization reaction rate distribution of the said ultraviolet-ray reaction material becomes also substantially uniform. Therefore, the irregular change in the pretilt angle also becomes small, and the occurrence of liquid crystal display nonuniformity also becomes small. In addition, since the heating of the liquid crystal is also suppressed, there is no fear of deterioration of the liquid crystal.

Since light having a wavelength of 300 nm or less is absorbed by the liquid crystal and there is a possibility that the liquid crystal may be damaged when the amount of irradiation is large, it is preferable that the lamp is a lamp that does not substantially emit light having a wavelength of 300 nm or less. In the rare gas fluorescent lamp shown in Fig. 1, almost no light having a wavelength of 300 nm or less is emitted.

In order to confirm the effect of this invention, the following experiment was done and the wavelength radiated from the lamp and the temperature rise of the liquid crystal panel were verified. The result is shown in FIG.

11 is a monomer (ultraviolet reaction material) for imparting a pretilt angle to a liquid crystal when irradiating a glass substrate used for a liquid crystal panel using three kinds of rare gas fluorescent lamps A to C and metal halide lamps. Irradiation time required for curing, radiation intensity and irradiation amount in a wavelength region of 310 nm to 360 nm, radiation intensity and irradiation amount in a wavelength region of 360 nm to 570 nm, and a glass substrate for using light from each lamp to the liquid crystal panel The temperature rise of the glass substrate at the time of irradiating with the irradiation time required for hardening of the said monomer is shown. The irradiation time varies depending on the illuminance and the ratio of the short wavelength included in the light to be irradiated. The irradiation time is shorter when the short wavelength is included, and the irradiation time is longer when the short wavelength is shorter.

In addition, the said irradiance is equivalent to said integrated irradiance, and an irradiation amount is the value which multiplied irradiation time by irradiation time.

Spectral emission spectra of the rare gas fluorescent lamps A to C are as shown in Figs. In addition, the spectral emission spectrum (using a filter) of the metal halide lamp is shown in FIG. In addition, the horizontal axis represents wavelength (nm) and the vertical axis represents spectral irradiance (μW / cm 2 / nm). The metal halide lamp is conventionally used in an ultraviolet irradiation device, and contains mercury and a metal halide inside. Iron halide (Fe) is used as a metal halide. Moreover, the light of wavelength 310nm or less is also emitted from the metal halide lamp which sealed mercury and iron halide. When the light emitted from the metal halide lamp is irradiated to the liquid crystal panel as described above, a large damage occurs to the liquid crystal. For this reason, in this experiment, the bandpass filter which cuts the wavelength of wavelength 310nm or less substantially was provided between the metal halide lamp and the liquid crystal panel. In addition, as described above, if the wavelength 310 nm light is 0, perfect curing is not obtained, and thus the bandpass filter is designed to transmit light of wavelength 310 nm to the extent that perfect curing is obtained without damaging the liquid crystal. It is.

As is apparent from Fig. 10, in the case of the metal halide lamp irradiated through the filter, the integrated emission illuminance a in the wavelength region of wavelength 360 nm or less is less than the integrated emission illuminance b of the wavelength region larger than the wavelength 360 nm. . In the wavelength region of 310 nm to 360 nm, the wavelength ratio on the short wavelength side is [rare gas fluorescent lamp A]> [rare gas fluorescent lamp B]> [rare gas fluorescent lamp C]> [metal halide lamp + filter].

In the case of the metal halide lamp used in this experiment, the time required for curing the monomer was 240 seconds, the integrated emission roughness at wavelength 310 nm to 360 nm was about 19.8 mW / cm 2, the irradiation amount was 4752 mJ / cm 2, and the wavelength was 360 nm. The integrated radiation illuminance at -570 nm was 86.2 mW / cm 2, and the irradiation amount was 20832 mJ / cm 2.

In addition, the temperature rise of the glass substrate at this time was 30 degreeC with air cooling nothing, and 7 degreeC with air cooling oil.

On the other hand, in the case of the rare gas fluorescent lamp A, the time required for curing the monomer is 180 seconds, the integrated emission roughness at wavelength 310 nm to 360 nm is 16.4 mW / cm 2, and the irradiation amount is 2952 mJ / cm 2, and the wavelength is 360 nm to The integrated emission illuminance at 570 nm was 10.2 mW / cm 2, and the irradiation amount was 1836 mJ / cm 2.

In addition, the temperature rise at this time was 5.1 degreeC, without air cooling.

In the case of the rare gas fluorescent lamp B, the time required for curing the monomer is 330 seconds, the integrated emission illuminance at wavelengths 310 nm to 360 nm is 11.6 mW / cm 2, and the irradiation amount is 3828 mJ / cm 2, and the wavelength is 360 nm to 570 nm. The integrated irradiance in was 10.1 mW / cm 2 and the irradiation amount was 3333 mJ / cm 2.

In addition, the temperature rise at this time was 7.6 degreeC, without air cooling.

In the case of the rare gas fluorescent lamp C, the time required for curing the monomer is 480 seconds, the integrated emission illuminance at wavelength 310 nm to 360 nm is 8.5 mW / cm 2, and the irradiation amount is 4080 mJ / cm 2, and the wavelength is 360 nm to 570 nm. The integrated irradiance in was 4.7 mW / cm 2 and the irradiation amount was 2256 mJ / cm 2.

In addition, the temperature rise at this time was 6.7 degreeC, without air cooling.

Moreover, the irradiation amount (310-360 nm) required for monomer hardening is [rare gas fluorescent lamp A] <[rare gas fluorescent lamp B] <[rare gas fluorescent lamp C] <[metal halide lamp]. It is thought that this is because the speed is faster and the required dose is reduced. As described above, in the wavelength region of 310 nm to 360 nm, the wavelength ratio on the short wavelength side is [rare gas fluorescent lamp A]> [rare gas fluorescent lamp B]> [rare gas fluorescent lamp C]> [metal halide lamp + filter ].

That is, in the case of a metal halide lamp, it is [integrated emission roughness a of wavelength range below wavelength 360nm] <[integrated emission roughness b of wavelength range larger than wavelength 360nm], and rare gas fluorescent lamps A, B, and C Is [integrated emission illuminance a in wavelength region of wavelength 360 nm or less]> [integrated emission illuminance b in wavelength region larger than wavelength 360 nm].

And when the glass substrate used for a liquid crystal panel was irradiated with the irradiation time required for hardening of a monomer using these lamps, the temperature rise of the glass substrate had the temperature of about 30 degreeC rising in the case of a metal halide lamp. In contrast, in the rare gas fluorescent lamps A, B, and C, only about 7.6 ° C. rose even if the temperature rise was the largest.

Here, in the rare gas fluorescent lamp B in which the temperature of the glass substrate has risen most in the rare gas fluorescent lamp, the irradiation amount in the wavelength region of 360 nm to 570 nm is 3333 mJ / cm 2, and the temperature rise at this time is 7.6 without air cooling. ° C. From this, when the irradiation amount in the wavelength region of 360 nm to 570 nm is set to about 3500 (mJ / cm 2) or less, the temperature rise of the color filter is suppressed, the temperature rise of the liquid crystal panel is suppressed to a minimum, and the pretilt angle is irregular. It is thought that the occurrence of a change can be suppressed.

For this purpose, in the apparatus for manufacturing a liquid crystal panel shown in FIG. 1, it is preferable that the control unit 4 controls the irradiation time to the liquid crystal panel, so that the irradiation amount is about 3500 (mJ / cm 2) or less.

Generally, liquid crystal will deteriorate when the temperature becomes 50 degreeC-60 degreeC or more. Therefore, when irradiating using a metal halide lamp, the temperature of a liquid crystal panel will be about 50 degreeC-60 degreeC, and a liquid crystal may deteriorate and may cause product defects. Spraying air or the like on the liquid crystal panel to cool down the temperature rise is suppressed, but for this purpose, a cooling mechanism is required, and the entire apparatus is enlarged, thereby increasing the cost.

On the other hand, if a rare gas fluorescent lamp is used, the temperature of the liquid crystal panel can be maintained at 35 ° C to 40 ° C or lower without cooling, and the deterioration of the liquid crystal can be prevented.

In addition, in the above, although the metal halide lamp was used as a control experiment of this invention, the experiment was performed using the high pressure mercury lamp, and the same result as the case of using a metal halide lamp was obtained.

1: light irradiation unit 1a: light source (lamp)
1b: mirror 1c: power
2: work stage 2a: mechanism for applying voltage
3: liquid crystal panel 3a, 3b: light transmissive substrate (glass substrate)
3c: liquid crystal containing ultraviolet reaction material
3d: sealing agent 4: control unit
10, 20, 30: lamp 11: container (light emitting tube)
12, 13 electrode 15, 27 phosphor layer
21 container (light emitting tube) 22, 23: electrode
31: discharge vessel 32, 33: electrode
24, 37: ultraviolet reflecting film

Claims (3)

A support unit for supporting an MVA liquid crystal panel having a color filter and containing a liquid crystal containing a photoreactive substance therein; and a light irradiation unit for irradiating light from a lamp to the liquid crystal panel supported by the support unit; And irradiating the light from the light irradiating portion with respect to the liquid crystal panel supported by the supporting portion, thereby reacting a photoreactive substance in the liquid crystal panel while applying a voltage to the liquid crystal panel to form an alignment portion inside the liquid crystal panel. In the manufacturing apparatus,
The lamp of the light irradiation part has a cumulative emission intensity of a wavelength range that contributes to the reaction of the photoreactive substance in the liquid crystal panel in the emission spectrum of the lamp, and is an absorption wavelength of the color filter and does not contribute to the reaction of the photoreactive substance. The integrated radiation illuminance of a lamp | ramp is a lamp whose a> b is integrated, when the integrated emission illuminance of the wavelength range which does not exist is b>, The manufacturing apparatus of the liquid crystal panel characterized by the above-mentioned. The method according to claim 1,
The integrated emission illuminance a is the integrated emission illuminance in the wavelength region of 310 nm to 360 nm, and the integrated emission illuminance b is the integrated emission illuminance in the wavelength region of 360 nm to 570 nm. The method according to claim 1 or 2,
The lamp is a rare gas fluorescent lamp that does not substantially emit light having a wavelength of 300 nm or less.

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