KR20010067131A - Light processing apparatus - Google Patents

Abstract

PURPOSE: To provide an optical processing device which makes optical processing possible without deteriorating the characteristics of a heat ray absorbing filter which suppresses the temperature increase of the object to be irradiated. CONSTITUTION: The light from a lamp 1 is successively passed through a far-UV ray cut filter 3 which removes or attenuates light in > 330 nm wavelength and through a heat ray absorbing filter 4 which removes or attenuates light in >= 750 nm wavelength, in this order to irradiate the object L of irradiation. The heat ray absorbing filter 4 is cooled by the cooling air flowing through an air passage 10 as a closed space.

Description

Light processing apparatus

The present invention relates to an optical processing apparatus for irradiating an ultraviolet ray to an irradiated object to react a substance causing a photochemical reaction applied to the irradiated object, and an optical processing apparatus suitable for joining two substrates using an ultraviolet curable adhesive. In particular, the present invention relates to an optical processing apparatus suitable for bonding a liquid crystal substrate in a manufacturing process of a liquid crystal display device.

Ultraviolet rays are irradiated from the light processing device to cure the protective film, the adhesive, the paint, the ink, the resist, and the like applied to the object by photochemical reaction with ultraviolet light, and to perform light irradiation treatment such as drying, melting and softening. In recent years, light irradiation processing is mainly performed, such as hardening and bonding of the protective film of the optical disc board | substrate with which aluminum was deposited, or bonding of the liquid crystal substrate provided with a color filter.

The liquid crystal substrate is made by bonding two transparent substrates or semi-transparent substrates together, and encapsulating liquid crystal therebetween. All. Bonding two liquid crystal substrates to an ultraviolet curable adhesive is disclosed, for example, in Japanese Patent Application Laid-Open No. 8-146436.

As an ultraviolet curable adhesive, it is generally used to make ultraviolet-ray with a wavelength of 365 nm into hardening wavelength. As the light source lamp, a discharge lamp that radiates this cured wavelength efficiently is selected. As a discharge lamp which efficiently emits ultraviolet rays around 365 nm, there is a metal halide lamp in which metal such as iron and mercury are enclosed.

FIG. 4 shows an example of the spectral radiant flux of a metal halide lamp in which iron and mercury are sealed. As can be seen from this, in such a metal halide lamp, in addition to ultraviolet rays having a wavelength of around 365 nm, far ultraviolet rays of 300 nm or less and infrared rays of a wavelength of 750 nm or more are also emitted. Therefore, when the light emitted from the metal halide lamp is irradiated onto two liquid crystal substrates as irradiated objects, infrared rays are absorbed by the substrate and the liquid crystal substrate is heated up. At this time, since the board | substrate of the board | substrate closer to a light source lamp is heated up large among two board | substrates, the difference of thermal expansion amount generate | occur | produces between two board | substrates, and when it bonds in this state, a position shift will arise between two board | substrates. And when this amount of position shift | deviation becomes 2-3 micrometers or more, it becomes a defect as a high precision liquid crystal display element which a pixel becomes thin.

When the irradiated object is not bonded to two substrates, for example, for curing the protective film of the optical disk, a photocurable acrylic resin is applied to the surface of the disk of the polycarbonate and irradiated with light having a wavelength of 300 to 400 nm. Even when the photocurable acrylic resin is dried and solidified, when the disk absorbs the infrared rays and heats up, "curvature" beyond the standard occurs on the disk, resulting in a defective product. In addition, even when drying film printing, for example, label printing on PET bottles, when the photocurable ink is dried by irradiating light having a wavelength of 300 to 400 nm, the plastic film is absorbed by infrared rays and heated up. There is an imbalance such as expansion and contraction occurs and color shift occurs in the case of multicolor printing.

In this manner, when performing the light irradiation treatment, an unbalance occurs when the temperature of the irradiated object is raised. Therefore, it is possible to arrange a heat ray absorption filter between the light source lamp and the irradiated object to suppress the temperature rise of the irradiated object. For example, in the manufacturing process of a liquid crystal display element, in order to prevent the temperature rise of a liquid crystal substrate, installing a heat ray absorption filter between a light source lamp and a liquid crystal substrate is disclosed by Unexamined-Japanese-Patent No. 11-153799.

Generally as a heat ray absorption filter, a color glass filter is used. This colored glass filter contains metal atoms in glass, and transmits light of short wavelengths well, but removes or attenuates long wavelengths of light by absorbing light of long wavelengths.

However, when the colored glass filter is irradiated with light having a wavelength of 330 nm or less, the characteristics of the colored glass filter deteriorate, the transmittance of light having a short wavelength decreases, and the transmittance of ultraviolet rays around 365 nm which is the curing wavelength of the ultraviolet curable adhesive Also significantly lowers. Since the metal halide lamp contains 300 nm or less of ultraviolet rays as described above, when the color glass filter is disposed between the metal halide lamp and the liquid crystal substrate and irradiated with light, the characteristic of the color glass filter is deteriorated. The transmittance of the curing wavelength decreases, and a long time is required for curing the adhesive, and the curing is not sufficiently performed. Therefore, for example, in the case of bonding of the liquid crystal display element, a decrease in throughput and poor adhesion are caused.

In addition, since the color glass filter absorbs the light having a long wavelength, the light having the long wavelength is removed or attenuated. Therefore, the light having the longer wavelength is converted into heat and the color glass filter itself is heated up. Therefore, the irradiated object may be heated by the radiant heat from a color glass filter. If the cooling wind is blown directly into the color glass filter or the irradiated object, the temperature can be prevented. However, when the irradiated object needs to be manufactured in a clean environment such as a liquid crystal display device, if a cooling wind is inadvertently blown into the color glass filter or the irradiated object, the cooling air disperses the flow of clean air that is set in the manufacturing environment in advance. It may cause dust.

Accordingly, a first object of the present invention is to provide an optical processing apparatus capable of performing light treatment without deteriorating the characteristics of the heat ray absorption filter that suppresses the temperature rise of the irradiated object, and a second object is to provide the characteristics of the heat ray absorption filter. An optical processing apparatus is provided that does not deteriorate and does not raise a temperature of irradiated object by radiant heat of a color glass filter.

1 is an explanatory diagram of an embodiment of the invention of claim 1;

2 is an explanatory diagram of an embodiment of the invention of claim 2;

3 is an explanatory diagram of an embodiment of the invention of claim 3;

4 is a diagram showing a spectral radiant flux of a lamp;

5 is a diagram showing a spectral radiant flux of light transmitted through an far ultraviolet cut filter;

6 is a view showing the spectral radiant flux of light transmitted through the far ultraviolet ray cut filter and the heat ray absorption filter;

7 is an explanatory diagram of characteristic deterioration of a heat ray absorption filter.

<Description of the symbols for the main parts of the drawings>

1: lamp 2: mirror

3: far ultraviolet ray cut filter 4: heat ray absorption filter

5: quartz plate 6: quartz plate

7: support frame 71: air supply

72: exhaust port 8: blower

9: duct 10: ventilation path

L: liquid crystal display element P1, P2: liquid crystal substrate

S: Adhesive

In order to achieve the first object, the invention of claim 1 is irradiated with ultraviolet light to the irradiated material coated with the material causing the photochemical reaction to react the material causing the photochemical reaction, irradiating light containing ultraviolet light And an ultraviolet ray cut filter for removing or attenuating light having a wavelength of 330 nm or less, and a heat ray absorbing filter for removing or attenuating light having a wavelength of 750 nm or more, wherein the light of the light source portion passes through the ultraviolet ray cut filter. Afterwards, the irradiated filter is irradiated to the irradiated object through the heat ray absorption filter.

In order to achieve the second object, in the invention of claim 2, in the invention of claim 1, a quartz plate is disposed on the irradiated object side of the heat ray absorption filter, and a ventilation path through which cooling air flows is formed between the heat ray absorption filter and the quartz plate. do. Moreover, in invention of Claim 3, the invention of Claim 1 forms the ventilation path through which a cooling wind flows between an far ultraviolet rays cut filter and a heat ray absorption filter.

The invention according to claim 4, in the light processing apparatus capable of attaining the first or second object, relates to an optical processing apparatus for adhering two substrates to the substrate with an ultraviolet curable adhesive. The present invention relates to an optical processing apparatus used in the bonding process of a liquid crystal substrate.

(Embodiment)

EMBODIMENT OF THE INVENTION Below, embodiment of this invention is described concretely with reference to drawings. 1 shows an embodiment of the invention of claim 1. In Fig. 1, the irradiated object is a liquid crystal display element (L). That is, UV curable adhesive S having a curing wavelength of 365 nm is applied on the peripheral edges of the two transparent or translucent liquid crystal substrates P1 and P2 so as to seal the space between the liquid crystal substrates P1 and P2. . And this liquid crystal display element L is arrange | positioned at the quartz plate 6 which is a support stand.

The lamp 1 is disposed below the quartz plate 6 on which the liquid crystal display element L as the irradiated object is disposed. The lamp 1 is a metal halide lamp in which iron and mercury are sealed in a tubular valve, and a lamp radiant output is 16 kW. As shown in Fig. 4, the spectral radiant flux efficiently emits light around 365 nm. The lamp 1 is covered with the cylindrical mirror 2, and the lamp 1 and the mirror 2 constitute a light source part. The direct light of the lamp 1 and the reflected light of the mirror 2 are emitted toward the liquid crystal display element L. FIG. Although the mirror 2 may use the total reflection mirror which reflects all the light from the lamp 1, it is preferable to use the "cold heat mirror" which deposited the multilayer film which permeate | transmits a long wavelength heat ray.

The ultraviolet ray cut filter 3 and the heat ray absorption filter 4 which is a color glass filter are arrange | positioned between the lamp | ramp 1 and the liquid crystal display element L to be irradiated. Here, the far ultraviolet cut filter 3 is disposed on the lamp 1 side, and the heat ray absorption filter 4 is disposed on the liquid crystal display element L side.

The far ultraviolet cut filter 3 is formed by depositing a multilayer film designed to reflect light having a wavelength of 330 nm or less on a quartz plate. The transmittance is, for example, 50% or less in the range of 300 to 330 nm, and 0% or less. to be. In other words, the light of 300 nm or less is completely removed, and the light having a wavelength of 300 to 330 nm is attenuated by 50% or more.

Since the color glass filter is often commercially available, the wavelength range of absorption is different. As the heat ray absorption filter 4 used in the present invention, the transmittance is 50% in the range of 720 to 730 nm and 1% in the range of 1001 to 1100 nm. Although the following is selected, what is necessary is just to have the characteristic which removes light of wavelength 750nm or more completely, or attenuates 50% or more.

The light in the vicinity of 365 nm emitted from the lamp 1 is transmitted to the liquid crystal display element L through the ultraviolet ray cut filter 3 and the heat ray absorption filter 4 in the order described later. Then, in the state where the liquid crystal display element L is pressed from above by the pressing means not shown, the adhesive S is cured by ultraviolet rays of 365 nm, and the two liquid crystal substrates P1 and P2 are joined. . When the bonding process is completed, the liquid crystal is injected into the space between the two liquid crystal substrates P1 and P2 from the injection hole provided in the periphery of the liquid crystal display element L.

FIG. 5 shows the spectral radiant flux of the light transmitted through the far ultraviolet cut filter 3, wherein far ultraviolet rays below 330 nm are either completely removed or greatly attenuated. And the light which permeate | transmitted the ultraviolet-ray cut filter 3 injects into the heat-ray absorption filter 4 which consists of a color glass filter. Fig. 6 shows the spectral radiant flux of the light transmitted through the heat ray absorption filter 4, whereby the light having a long wavelength of 750 nm or more is almost removed, and only the ultraviolet ray around 365 nm is irradiated. Irradiated to the liquid crystal display element L, and the adhesive S with a curing wavelength of 365 nm is cured efficiently.

As described above, since the ultraviolet ray of 330 nm or less removed or greatly attenuated by the ultraviolet ray cut filter 3 is incident on the heat ray absorption filter 4 made of a color glass filter, the characteristic of the heat ray absorption filter 4 is deteriorated. Is suppressed. 7 shows a characteristic deterioration curve of a heat ray absorption filter.

In Fig. 7, the dotted line curve shows a characteristic deterioration curve of a conventional example in which the light emitted from the discharge lamp is incident on the heat absorption filter as it is without using an ultraviolet ray cut filter. The transmittance of light greatly decreases with the irradiation time, and decreases approximately 25-30% at about 60-65% at 100 hours of irradiation time. Therefore, the ultraviolet-ray of wavelength 365nm which is the hardening wavelength of an adhesive agent attenuates greatly.

On the other hand, the solid curve shows the characteristic deterioration curve in the embodiment of the present invention, but the decrease in the transmittance of light having a wavelength of 365 nm is about 10% even when irradiated for 90 hours. Therefore, even if it irradiates for a long time, the attenuation of the ultraviolet-ray of wavelength 365nm which is the hardening wavelength of an adhesive agent can be suppressed by half, and the fall of the throughput of a liquid crystal display element L and a bad adhesion can be prevented.

In addition, since the ultraviolet ray cut filter 3 and the heat ray absorption filter 4 pass through, and the light of the spectral radiation flux shown in FIG. 6 is irradiated to the liquid crystal display element L as an irradiated object, infrared rays are not irradiated to the liquid crystal substrate. Therefore, the liquid crystal display element L hardly warms up. As a result, the temperature difference between the two liquid crystal substrates P1 and P2 is very small, and the “deviation” of the two liquid crystal substrates P1 and P2 due to the difference in the amount of thermal expansion does not occur, so that the product yield can be improved. .

2 shows an embodiment of the invention of claim 2. The liquid crystal display element L as the irradiated object, the lamp 1 and the mirror 2 as the light source portion are the same as those of the invention of claim 1 shown in FIG. Since the heat ray absorption filter 4 is hardly commercially available, the several heat ray absorption filter 4 of about 50x50 mm is arranged on the far ultraviolet ray cut filter 3. The characteristics of the far ultraviolet cut filter 3 and the heat ray absorption filter 4 are as described above.

In the support frame 7 supported by the heat ray absorption filter 4 and the far ultraviolet cut filter 3, an air supply port 71 and an exhaust port 72 are formed on the side thereof, and the upper and lower surfaces thereof are open. The heat ray absorption filter 4 and the far ultraviolet ray cut filter 3 are supported so as to cover the open lower surface of the support frame 7. The blower 8 for cooling wind is connected to the air supply port 71 through the duct 9, and the duct 9 which guides exhaust air to the outside is also connected to the exhaust port 72. As shown in FIG. The quartz plate 5 is supported to cover the open upper surface of the support frame 7, and the closed space defined by the heat ray absorption filter 4, the quartz plate 5 and the support frame 7 is cooled. A ventilation path 10 is provided. Then, when the blower 8 is operated, the cooling wind flowing through the ventilation path 10 absorbs the light having a long wavelength to cool the heat ray absorption filter 4 that has been heated up. Moreover, it is good also as a ventilation type cooling apparatus provided with the blower 8 in the exhaust port 72 side.

3 shows an embodiment of the invention of claim 3. Here, a single heat ray absorption filter 4 of the same dimension as the far ultraviolet ray cut filter 3 is used, and the far ultraviolet ray cut filter 3 and the heat ray absorption filter 4 are provided with the lower surface of the support frame 7. It is supported so as to cover the upper surface, respectively. The closed space defined by the heat ray absorption filter 4, the far ultraviolet cut filter 3, and the support frame 7 forms the ventilation path 10 of the cooling wind. The other structure is the same as that of embodiment of invention of Claim 2 shown in FIG.

2 and 3, when the blower 8 is operated and the lamp 1 is turned on, ultraviolet rays in the vicinity of 365 nm of the light emitted from the lamp 1 are exposed to the ultraviolet cut filter 3 and the heat ray absorption. The adhesive S is cured by passing through the filter 4 and irradiating the liquid crystal display device L. At this time, since the light of 330 nm or less is removed or attenuated by the ultraviolet ray cut filter 3, the deterioration of characteristics of the heat ray absorption filter 4 does not occur, and the light having a long wavelength of 750 nm or longer is removed by the heat ray absorption filter 4. Since the liquid crystal display element L does not absorb long wavelength light and does not warm up, it is possible to prevent "shifting" of the two liquid crystal substrates P1 and P2 due to the difference in thermal expansion amount. It is the same as embodiment of invention of Claim 1 shown in FIG.

And since the heat-ray absorption filter 4 which absorbed the long wavelength light and heated it up by the cooling wind sent from the blower 8 is cooled, radiant heat is hardly radiated | emitted from the heat ray absorption filter 4, The liquid crystal which is an irradiated object A great effect can be obtained in preventing the temperature rise of the display element L.

2, the input of the lamp 1 is 200W, the distance between the lower liquid crystal substrate P2 and the quartz plate 5 is 550 mm, and the size of the liquid crystal substrate P2 is 370 x 470 mm. When the color filter is installed on the substrate P2, if the air flow rate of cooling air is 3.5 m 3 / min, the temperature difference between the two liquid crystal substrates P1 and P2 is about 0.9 to 1.3 deg, and the two liquid crystal substrates P1 and P2 are used. The "deviation" of 2 to 3 micrometers or less turns out that there is no problem practically even in the bonding of a high-precision liquid crystal display element.

In addition, since the cooling wind is discharged to the outside through the ventilation path 10 of the closed space, the cooling air can be subjected to light irradiation treatment while maintaining a clean environment without disturbing the flow of clean air that is set in the manufacturing environment. have.

In the embodiment of the invention of claim 2 shown in Fig. 2, since the multiple heat ray absorption filters 4 are arranged without being fixed to each other, when the heat ray absorption filter 4 absorbs the long wavelength light and heats up, the thermal expansion It can be absorbed by the minute gap which arises between the heat ray absorption filters 4, and there exists an advantage which can prevent the troubles, such as a deformation | transformation and damage by the thermal expansion of the heat ray absorption filter 4, and the like.

In the heat ray absorption filter 4, the lower surface (surface on the side of the lamp 1 side) on which the light of the lamp 1 enters becomes a high temperature. In the embodiment of the invention of claim 3 shown in FIG. Since the lower surface of the absorption filter 4 is cooled by a cooling wind, there is an advantage that the heat ray absorption filter 4 can be efficiently cooled.

In the above embodiment, the irradiated object was a liquid crystal display element L for joining two liquid crystal substrates P1 and P2. However, for example, two plate-like objects are bonded to each other, such as a protective film curing treatment of an optical disk or a drying treatment of printing of a film. However, the present invention can be effectively applied even when an imbalance occurs by absorbing and heating the light having a long wavelength at the time of light irradiation treatment.

As described above, the light of the lamp passes through an ultraviolet ray cut filter for removing or attenuating light having a wavelength of 330 nm or less, and a heat ray absorbing filter for removing or attenuating light of a wavelength of 750 nm or more. Since it is irradiated, the characteristic deterioration of a heat ray absorption filter does not generate | occur | produce and can irradiate a to-be-irradiated ultraviolet ray near 365 nm effectively for a long time, and it can prevent that a to-be-absorbed object absorbs light of long wavelength and heats up. In addition, since the heat ray absorption filter is cooled by a cooling wind flowing through a ventilation path that is a closed space, the temperature rise of the heat ray absorption filter that absorbs the light of long wavelength can be prevented, and the irradiated heat of the heat radiation absorption filter is irradiated. A great effect can be obtained to prevent the temperature rise. Accordingly, the present invention can be effectively applied to light irradiation treatment, although the defective rate increases when the irradiated object is heated, such as two liquid crystal substrates on which the irradiated object is bonded with an ultraviolet curable adhesive.

Claims (5)

In the light irradiation apparatus which irradiates the irradiated material to which the substance which causes a photochemical reaction with ultraviolet-ray, and reacts the substance which produces the said photochemical reaction, A light source unit for irradiating light including ultraviolet rays, an ultraviolet ray cut filter for removing or attenuating light having a wavelength of 330 nm or less, and a heat ray absorbing filter for removing or attenuating light having a wavelength of 750 nm or more; The light of the light source unit is transmitted to the irradiated object after passing through the ultraviolet ray cut filter, the heat ray absorption filter. The method of claim 1, A quartz plate is disposed on the irradiated object side of the heat ray absorption filter, and a ventilation path through which a cooling wind flows is formed between the heat ray absorption filter and the quartz plate. The method of claim 1, And a ventilation path through which a cooling wind flows between the far ultraviolet cut filter and the heat ray absorption filter. The method according to any one of claims 1, 2 and 3, The material causing the photochemical reaction is an ultraviolet curable adhesive, and the irradiated object is two substrates, and the two optical substrates are bonded to each other by irradiating ultraviolet rays to the adhesive applied between the two substrates. The method of claim 4, wherein And the substrate is a liquid crystal substrate.