KR20110036665A - Light irradiation apparatus - Google Patents

Abstract

PURPOSE: A light irradiating apparatus is provided to irradiate light on a sealing layer by selecting an LED element according to the sensitivity wavelength region of an optical polymerization component. CONSTITUTION: An optical polymerization material layer(2) contains an optical polymerization component in a sensitivity wavelength region. A sealing layer(3) includes an optical sealing material. A filter shields the light on a short wavelength side having cutoff wavelength on a long wavelength side. The light, which is emitted from an LED element, is irradiated to the sealing layer through the filter.

Description

Light irradiation apparatus {LIGHT IRRADIATION APPARATUS}

This invention relates to the light irradiation apparatus used as a light source of the bonding apparatus of the display panel for bonding two translucent board | substrates with the photocuring sealing agent in manufacturing processes of display panels, such as a liquid crystal panel.

Recently, in the liquid crystal panel, a PSA (Polmer Sustained Aligment) method or a PSVA method for regulating the orientation direction of liquid crystal molecules by a polymer structure instead of a rib structure formed inside a cell for the purpose of improving contrast and improving response speed. Is developed.

In the manufacturing process of this PSA system liquid crystal panel, a polymer structure is formed in a cell by inject | pouring the liquid crystal material containing a photopolymerizable component in a cell, and irradiating an ultraviolet-ray, applying a voltage to the injected liquid crystal material. . In the liquid crystal dropping method (One Drop Fill, ODF) which is one of the methods of fixing this liquid crystal material to a liquid crystal panel, it forms a frame shape by apply | coating a photocuring sealing agent to the surface of one translucent board which comprises a cell. After forming the sealing agent layer of this, and apply | coating the liquid crystal material containing a monomer to the area | region enclosed by the sealing agent layer in the surface of the said one translucent board | substrate, the other translucent board | substrate was overlaid, and the display Light is irradiated to the sealing agent layer by the bonding apparatus of a panel, the said sealing agent is hardened, and two light-transmissive substrates are bonded together. Then, the polymer structure is formed by irradiating an ultraviolet-ray with the monomer contained in a liquid crystal material, and the cell in which the liquid crystal material was inject | poured is formed.

And as a photocuring sealing agent, what shifted the sensitivity wavelength range toward the longer wavelength side rather than the sensitivity wavelength range of the photopolymerizable component in a liquid crystal material so that the polymerization reaction of the photopolymerizable component contained in a liquid crystal material may not progress when light is irradiated. Is used.

On the other hand, in the bonding apparatus of a display panel, as a light source for irradiating light to a sealing agent layer, it is provided with the lamp which radiates the light of the sensitivity wavelength range of a photocurable sealing agent, and the filter which shields the light of a short wavelength side. The light irradiation apparatus is used (refer patent document 1).

Japanese Patent Publication No. 2003-149647

However, such a light irradiation apparatus has the following problems.

(1) In general, since the lamp requires a considerable time from the start of the lighting to the normal lighting state, i.e., the instantaneous lighting is difficult, in the light irradiation apparatus, the lamp is continuous by providing a shutter mechanism. In the lit state, light is irradiated to the irradiation object when necessary by opening and closing the shutter of the shutter mechanism. For this reason, there is a problem that the energy efficiency is low, and the movable parts in the shutter mechanism tend to be a cause of failure and the reliability of the device is low.

(2) The emission spectrum of the lamp has a wavelength range of 200 to 450 nm, which is a sensitivity wavelength of the photocurable sealing agent at a wavelength of 200 to 600 nm (see paragraph 0238 of Patent Document 1). Compared with paragraph 0244.), since the long wavelength side is considerably wider and light in the wavelength region on the short wavelength side is shielded by the filter, there is a problem that the utilization efficiency of light is very low.

(3) As a filter, a filter having a dielectric multilayer film is generally used, but in such a filter, it is difficult to sufficiently shield light of a desired wavelength range depending on the incident angle dependence, that is, depending on the incident angle of light. . Therefore, although the mask is normally used for the purpose of preventing light from irradiating to a liquid crystal material, since this mask needs to be prepared according to the form, dimensions, etc. of the display panel to manufacture, manufacturing cost is There is a problem of increasing.

This invention is made | formed in view of the above circumstances, The objective is the light irradiation apparatus used for the bonding apparatus of the PSA system display panel, For example, it is the polymerization reaction of the photopolymerizable component contained in a liquid crystal material. It is providing the light irradiation apparatus which can irradiate and harden | cure a sealing agent layer by high light utilization efficiency, without advancing.

The light irradiation apparatus of the present invention has a photopolymerizable material layer containing a photopolymerizable component having a sensitivity wavelength range in a constant range, and a sensitivity wavelength region surrounding the photopolymerizable material layer is higher than the sensitivity wavelength region of the photopolymerizable component. It is used for the bonding apparatus of the display panel which joins the said two transparent substrates by irradiating light to the said sealing agent layer in the state in which the sealing agent layer which consists of a photocurable sealing agent in the long wavelength side was formed between two light-transmissive substrates. In the light irradiation apparatus,

And a filter for shielding light on the short wavelength side that is shorter than the emission peak wavelength of the LED element and that has a cutoff wavelength on the longer wavelength side than the shortest wavelength of the emission spectrum of the LED element. Light emitted is irradiated to the sealing agent layer through the filter.

In the light irradiation apparatus of this invention, it is preferable that the cutoff wavelength of the said filter is in a longer wavelength side rather than the long wavelength side end of the sensitivity wavelength range of the said photopolymerizable component.

Moreover, it is preferable that the some light source segment in which several of the said LED element is arrange | positioned on the same board | substrate is arrange | positioned so that it may be lined up along the surface direction of the said board | substrate.

Moreover, it has a LED package in which the said LED element is accommodated, and the said filter may be provided in the said LED package.

According to the light irradiation apparatus of this invention, the light from the LED element whose wavelength range of a light emission spectrum is narrow is short wavelength side rather than the emission peak wavelength of this LED element, and is cut-off wavelength to the longer wavelength side than the shortest wavelength of the light emission spectrum of this LED element. Since the light is irradiated through a filter having a wavelength, the wavelength distribution of the irradiated light becomes very narrow. Therefore, the LED element is selected according to the sensitivity wavelength range of the photocurable sealing agent constituting the sealing agent layer and the sensitivity wavelength range of the photopolymerizable component in the photopolymerizable material layer to thereby advance the polymerization reaction of the photopolymerizable component in the photopolymerizable material layer. It can irradiate and harden | cure a sealing compound layer with high utilization efficiency of light, without making it make it impossible.

In addition, since the LED element has a very short time from the start of the lighting to the normal lighting state, i.e., the instantaneous lighting can be performed, it is unnecessary to provide continuous lighting and to provide a shutter mechanism, and therefore high energy. In addition to obtaining efficiency, high reliability can be obtained.

Moreover, according to the structure which uses a cut-off wavelength which is longer in the longer wavelength side than the longer wavelength side end of the sensitivity wavelength range of the photopolymerizable component in a photopolymerizable material layer, when light is irradiated to the sealing agent, the light in a photopolymerizable material layer It is possible to reliably prevent the polymerization reaction of the synthetic components from proceeding.

According to the configuration in which a plurality of light source segments in which a plurality of LED elements are arranged on the same substrate are arranged along the plane direction of the substrate, the seal is selected by selecting a light source segment to be lit depending on the shape of the sealing agent layer. Since light can be selectively irradiated to the ring agent layer, higher energy efficiency can be obtained and a mask is not required to selectively irradiate light to the sealing agent layer, thereby reducing manufacturing costs. We can plan. Moreover, when one LED element in a light source segment deteriorates, the intensity | strength of the light quantity stabilized on the whole light source segment can be irradiated by raising the irradiation intensity of another LED element.

In addition, the LED package has an LED element housed therein, and according to the configuration in which the filter is installed in the LED package, it becomes unnecessary to install a large-area filter, so that the cost of the filter can be reduced and the productivity can be improved. have.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the outline of the structure in an example of the bonding apparatus of the display panel provided with the light irradiation apparatus which concerns on this invention.
It is a top view which shows the process target of the bonding apparatus of the display panel shown in FIG.
It is a top view which shows the structure in an example of the light irradiation apparatus which concerns on this invention.
It is explanatory drawing which shows the structure of the light source segment in the light irradiation apparatus shown in FIG.
5 is a curve diagram schematically showing the relationship between the emission spectrum of the LED element and the spectral characteristics of the filter.
It is explanatory drawing which shows the structure of the light source segment in the other example of the light irradiation apparatus of this invention.
FIG. 7: is explanatory drawing which shows the structure of the LED package in the light source segment shown in FIG.
It is explanatory drawing which shows the structure of the principal part of the modification of a light source segment.
9 is an explanatory diagram showing a configuration of another modified example of the light source segment.
It is explanatory drawing which shows the structure of the modification of an LED package.
11 is a luminescence spectrum diagram relating to a light source segment in the light irradiation apparatus according to Example 1 and Comparative Example 1. FIG.
It is a figure which shows the sensitivity curve of a typical photocurable sealing agent.
It is a synthetic | combination curve figure which multiplied the emission spectrum of the light irradiation apparatus in the Example with the sensitivity curve of a photocurable sealing agent.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the outline of the structure in an example of the bonding apparatus of the display panel provided with the light irradiation apparatus which concerns on this invention.

In the bonding apparatus (hereinafter only referred to as "bonding apparatus") of this display panel, a stage 10 on which the object to be processed is placed on the base 11 via the support 12 is provided. Above light 10, the light irradiation apparatus 15 which concerns on this invention is arrange | positioned.

In the object 1 of the bonding apparatus, the photopolymerizable material layer 2 and the sealing agent layer 3 surrounding the circumference of the photopolymerizable material layer 2 include two light-transmitting substrates 4. It is formed in between. The object 1 of this example is for manufacturing a total of four display panels. In the object 1, as shown in FIG. 2, four photopolymerizable material layers are vertically and horizontally spaced apart from each other. Four sealing agent layers 3 surrounding (2) and one photopolymerizable material layer 2 are formed.

The photopolymerizable material layer 2 is comprised by the photopolymerizable component in which the sensitivity wavelength range is constant, and the liquid crystal material containing a liquid crystal component. The photopolymerizable component in the photopolymerizable material layer 2 contains a monomer and a photopolymerization initiator which generates active species such as radicals or cations by receiving ultraviolet rays. The sensitivity wavelength range of this photopolymerizable component is determined by selecting the kind of photoinitiation start.

Moreover, the sealing agent layer 3 consists of a photocuring sealing agent, This photocuring sealing agent contains the photoinitiator which generate | occur | produces active species, such as radical or cation, by receiving curable resin and an ultraviolet-ray. The photocurable sealing agent has a longer wavelength side end of the sensitivity wavelength range than the long wavelength side end of the sensitivity wavelength range of the photopolymerizable component in the photopolymerizable material layer 2. The sensitivity wavelength range of a photocuring sealing agent is determined by selecting the kind of photoinitiator.

In addition, the light transmissive substrate 4 is made of glass or the like.

The object 1 is formed by applying a photocurable sealing agent to the surface of one light-transmissive substrate 4 to form four sealing agent layers 3 in a frame shape, respectively, and the light-transmissive substrate 4 as described above. After forming four photopolymerizable material layers 2 by apply | coating the liquid crystal material containing a photopolymerizable component and a liquid crystal component to the area | region enclosed in each of the sealing agent layer 3 in the surface of About one translucent board | substrate 4, it is obtained by laminating | stacking the other translucent board | substrate in the state spaced apart at predetermined intervals.

As shown in FIG. 3, the light irradiation apparatus 15 of the example of illustration is arrange | positioned so that the some light source segment 20 may be vertically and horizontally arranged on a suitable support body (not shown).

In each of the light source segments 20, as shown in FIG. 4, a plurality of LED elements 25 are disposed on the surface of the same rectangular substrate 21, and on each surface of these LED elements 35, The filter 30 is provided so that the said LED element 25 may be covered.

Moreover, the rectangular cylindrical light guide member 26 whose inner surface became a light reflection surface is arrange | positioned at the periphery part in the surface of the board | substrate 21, and the LED element 25 emits on the back surface of the said board | substrate 21. The heat radiation fins 27 for dissipating heat are provided.

As the LED element 25, a gallium nitride (GaN) -based LED containing indium (In) and aluminum (Al) can be used. The emission spectrum of the LED element 25 is selected according to the sensitivity wavelength range of the photopolymerizable component which comprises a photopolymerizable material layer, and the sensitivity wavelength range of the photocurable sealing agent which comprises a sealing agent layer, and In, AlGa, By adjusting the composition ratio of N, although the peak wavelength can obtain the LED element 25 from 200 nm to an infrared region, specifically, the peak wavelength is selected from 360-420 nm.

Moreover, the half value width of the peak wavelength in the emission spectrum of the LED element 25 is 10-30 nm, for example.

In addition, the number of LED elements 25 in each of the light source segments 20 is 5-16, for example.

The filter 30 is a long pass filter that shields light on the short wavelength side, and the cutoff wavelength (wavelength at which the light transmittance is 50%) is on the shorter wavelength side than the emission peak wavelength of the LED element 25, The wavelength is longer than the shortest wavelength of the emission spectrum of the LED element 25. As such a filter 30, what has a dielectric multilayer film can be used.

Moreover, it is preferable that the cut-off wavelength of the filter 30 exists in the longer wavelength side rather than the long wavelength side end of the sensitivity wavelength range of the photopolymerizable material layer 2, Therefore, light is applied to the sealing agent layer 3 When irradiated, it can reliably prevent the polymerization reaction of the photopolymerizable component in the photopolymerizable material layer 2 from advancing.

In the light irradiation apparatus 15, the light source segment 20 selected according to the shape of the sealing agent layer 3 in the object 1 among all the light source segments 20 is operated, whereby the light source segment ( The light from the LED element 25 in 20 is emitted from the light exit portion 28 of the light guide member 26 through the filter 30 and disposed on the stage 10 of the bonding apparatus. It is irradiated to the sealing agent layer 3 in (1), and the sealing agent layer 3 hardens by this.

In the above, the LED element 25 has the emission spectrum shown by the curve L, as shown typically in FIG. 5, but the filter 30 has the spectral characteristic shown by the curve F That is, since it is a long pass filter which has a wavelength shorter than the peak emission wavelength of the LED element 25, and has a cut-off wavelength which is longer than the shortest wavelength of the emission spectrum of the said LED element 25, the LED element 25 will emit | emit Among the lights, light having a wavelength shorter than the cutoff wavelength of the filter 30 (light of the oblique portion in FIG. 5) is shielded by the filter 30.

According to such a light irradiation apparatus 15, the light from the LED element 25 with a narrow wavelength range of an emission spectrum is shorter wavelength than the emission peak wavelength of this LED element 25, and light emission of the said LED element 25 is carried out. Since it irradiates through the filter 30 which has a cutoff wavelength in the long wavelength side rather than the shortest wavelength of a spectrum, the wavelength distribution of the irradiated light becomes very narrow. The sensitivity wavelength range of the sealing agent layer 3 is higher on the short wavelength side, but as the light source of the display panel bonding apparatus, light in the sensitivity wavelength range of the photopolymerization component in the photopolymerizable material layer 2 cannot be irradiated. Therefore, by shielding light on the shorter wavelength side than the light emission peak wavelength of the light from the LED element by the filter, the sealing region 3 is a wavelength region excluding the sensitivity wavelength range of the photopolymerizable component in the photopolymerizable material layer 2. The light of the short wavelength range with high sensitivity of the photocurable sealing agent to be comprised can be irradiated more strongly. For this reason, the sealing agent layer 3 can be irradiated with light and hardened | cured with high utilization efficiency of light, without advancing the polymerization reaction of the photopolymerizable component in the photopolymerizable material layer 2 by this.

In addition, since the LED element 25 has a very short time from the start of the lighting to the normal lighting state, i.e., the instantaneous lighting is possible, it is unnecessary to provide continuous lighting and to provide the shutter mechanism. In addition, high energy efficiency can be obtained and high reliability can be obtained.

The plurality of LED elements 25 has a plurality of light source segments 20 formed on the same substrate 21, and these light source segments 20 are arranged to line up along the surface direction of the substrate 21. Therefore, by selecting the light source segment 20 to be turned on in accordance with the shape of the sealing agent layer 3, light can be selectively irradiated to the sealing agent layer 3, so that a higher energy efficiency can be obtained. Since it becomes unnecessary to provide a mask in order to selectively irradiate light to the sealing agent layer 3, manufacturing cost can be reduced. In addition, when one LEID element 25 in the light source segment 20 deteriorates, by increasing the irradiation intensity of the other LED element 25, it is possible to irradiate light with a stable amount of light on the entire light source segment 20. .

It is explanatory drawing which shows the structure of the light source segment in the other example of the light irradiation apparatus of this invention.

In this light source segment 20, the several LED package 35 is arrange | positioned on the surface of the same rectangular board | substrate 21, and the inner surface is a rectangle whose inner surface is a light reflection surface in the peripheral part in the surface of the said board | substrate 21. The light guide member 26 of the cylindrical shape is arrange | positioned, and the heat radiation fin 27 which dissipates the heat which the LED package 35 radiates is provided in the back surface of the said board | substrate 21. As shown in FIG.

As shown in FIG. 7, each of the LED packages 35 has a package substrate 36 having a rectangular recess 37 formed at the center thereof, and in the recess 37 of the package substrate 36. The LED element 25 is arrange | positioned, and the plate-shaped filter 30 is provided so that the recessed part 37 of the said package substrate 36 may be prevented. 28 is a light exit portion of the light guide member 26. The characteristics of the LED element 25 and the filter 30 are the same as those in the light source segment 20 shown in FIG.

According to such a light irradiation apparatus, the same effect as the light irradiation apparatus shown to FIG. 3 and FIG. 4 is acquired, and it has the LDE package 35 in which the LED element 25 is accommodated, and this LED package 35 ), The filter 30 is provided, so that it is unnecessary to provide the large-area filter 30. As a result, the cost of the filter can be reduced and the productivity can be improved.

The light irradiation apparatus of this invention is not limited to said embodiment, It is possible to add various changes.

(1) In the light source segment 20 shown in FIG. 4, as shown in FIG. 8, the filter 30 may be hemispherical having a lens function.

Moreover, instead of providing the filter 30 in each of the LED elements 25, as shown in FIG. 9, one filter 30 is provided at a central position in the through hole of the light guide member 26. The structure may be sufficient.

Moreover, as shown in FIG. 9, the integrator lens 29 may be arrange | positioned in the front end side position in the cylinder hole of the light guide member 26. As shown in FIG.

(2) In the light source segment 20 shown in FIG. 6, the filter 30 provided in the LED package 35 may be hemispherical having a lens function as shown in FIG. 10 (a).

Moreover, the lens 31 may be provided in the LED package 35 on the surface of the plate-shaped filter 30, as shown to FIG. 10 (b).

(Example 1)

<Example 1>

According to the structure shown in FIG. 3 and FIG. 4, the light irradiation apparatus which has arrange | positioned so that 130 light source segments may be lined vertically and horizontally was produced. The specification of the light source segment is as follows.

The longitudinal and horizontal dimensions of the substrate 21 are 50 mm x 50 mm, and the total length of the light guide member 26 is 45 mm.

The LED element 25 has a peak wavelength of 385 nm and a half width of ± 5 nm in the emission spectrum, and is provided in nine light source segments.

The filter 30 is a long pass filter having a dielectric multilayer film, and its cutoff wavelength is 380 nm.

Fig. 11A shows a light emission spectrum diagram relating to the light source segment in this light irradiation apparatus.

<Comparative Example 1>

As the LED element 25, the light irradiation apparatus of the same structure as Example 1 was used except having used the peak wavelength of luminescence spectrum of 405 nm, the half value width of +/- 8 nm, and having not provided the filter 30. Made.

The emission spectral diagram which concerns on the light source segment in this light irradiation apparatus is shown in FIG.

<< hardening test of sealing agent >>

Using the light irradiation apparatus which concerns on Example 1 and the comparative example 1, the hardening test of the sealing agent was done as follows.

Two types of photocurable sealing agents each having a sensitivity curve as shown in FIG. 12 (these are referred to as "sealing agent A" and "sealing agent B"), each having a thickness of several micrometers between two light-transmissive substrates The sealing agent layer was formed. Light is irradiated to this sealing agent layer with the light irradiation apparatus on the conditions that the intensity | strength on an irradiation surface will be 155 ㎽ / cm <2>, and accumulated irradiation light quantity 500mJ / cm <2>, 750mJ / cm <2>, 1000mJ / cm <2> and 2000mJ The hardening rate of the sealing agent layer when it became / cm <2> was measured.

As mentioned above, the hardening rate of the sealing agent layer was measured by the analysis of the infrared absorption spectrum which changes according to the chemical structure change which changes with hardening reaction by FT-IR (Fourier Transform Infrared Absorption Spectroscopy) method. Specifically, the consumption amount of the chemical bond which disappears by polymerization was quantified based on the area or height of the infrared absorption peak, and the curing rate was calculated based on the value.

Moreover, in practical use, it is judged that the sealing agent layer was hardened as the hardening rate is 80% or more.

The results are shown in Table 1 above.

As is apparent from the results in Table 1, in the light irradiation apparatus according to Example 1, curing is performed when the light is irradiated under a condition that the amount of accumulated irradiation light is 500 mJ / cm 2 or more for both the sealing agent A and the sealing agent B. It was confirmed that it could be done.

On the other hand, in the light irradiation apparatus which concerns on the comparative example 1, in order to harden a sealing agent layer, accumulated irradiation light quantity is 2000 mJ / cm <2> or more about sealing agent A, and integrated irradiation light quantity is 1000 mJ / cm <2> or more with respect to sealing agent B It was necessary to irradiate light on these conditions.

13 is a synthetic curve diagram obtained by multiplying the emission spectrum of the light irradiation apparatus by the sensitivity curve of the photocurable sealing agent, and (A1) shows the emission curve of the light irradiation apparatus according to Example 1 and the sensitivity curve of the sealing agent A. FIG. The synthetic curve multiplied by (A2) is a synthetic curve obtained by multiplying the emission spectrum of the light irradiation apparatus according to Comparative Example 1 by the sensitivity curve of the sealing agent A.

In these synthesis curves, each integral value can be regarded as the reaction amount of the photocurable sealing agent per unit irradiation time, and the integral value of the synthesis curve of (A1) was 1.6 times the integral value of the synthesis curve of (A2).

Thus, according to the light irradiation apparatus which concerns on Example 1, it is understood that high light utilization efficiency can be acquired compared with the light irradiation apparatus which concerns on the comparative example 1. As shown in FIG.

1: object to be treated 2: photopolymerizable material layer
3: sealing agent layer 4: translucent board | substrate
10: stage 11: expectation
12: support 15: light irradiation device
20: light source segment 21: substrate
25 LED device 26 light guide member
27: heat radiation fin 28: light output unit
29: integrator lens 30: filter
31 Lens 35 LED Package
36: package substrate 37: recess

Claims (4)

A photocurable material layer containing a photopolymerizable component having a sensitivity wavelength range in a constant range, and a photocurable sealing ring having a sensitivity wavelength range surrounding the photopolymerizable material layer on a longer wavelength side than the sensitivity wavelength range of the photopolymerizable component. In the light irradiation apparatus used for the bonding apparatus of the display panel which bonds the said two transparent substrates by irradiating light to the said sealing agent layer in the state in which the sealing agent layer which consists of two is formed between two transparent substrates,
And a filter for shielding light on the short wavelength side that is shorter than the emission peak wavelength of the LED element, and which has a cutoff wavelength on the longer wavelength side than the shortest wavelength of the emission spectrum of the LED element. Light emitted is irradiated to the said sealing agent layer through the said filter, The light irradiation apparatus characterized by the above-mentioned. The method according to claim 1,
The cutoff wavelength of the said filter is a longer wavelength side than the longer wavelength side edge part of the sensitivity wavelength range of the said photopolymerizable component, The light irradiation apparatus characterized by the above-mentioned. The method according to claim 1 or 2,
A plurality of light source segments in which a plurality of the LED elements are arranged on the same substrate are arranged so as to be arranged along the plane direction of the substrate. The method according to claim 1 or 2,
The LED irradiation element which has the said LED element accommodated, The said LED package is provided with the said filter, The light irradiation apparatus characterized by the above-mentioned.

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