JP3307656B2 - Color display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color display device. More specifically, the present invention relates to a color liquid crystal display device.

[0002]

2. Description of the Related Art A color filter is widely used such as a liquid crystal color display plate, a filter for a single-tube type color television camera, a color phase plate for a CRT display, and a plate for a photoelectric conversion element for copying. Also,
Most of these color filters have a color filter adhered to a substrate such as a liquid crystal display device or a group image pickup device such as a CCD, a MOS, and a BBD.

As a resin used for the adhesive, a thermosetting resin, an ultraviolet curing resin, or an X-ray curing resin can be used.

[0004] However, when the display element and the color filter are bonded, alignment accuracy is severe, and a thermosetting resin is misaligned due to a difference in thermal expansion, especially on a large substrate, when heated, resulting in poor accuracy.

In the case of a UV-curable resin, it is possible to precisely align the picture element portion of the display element with the color filter by using a high-precision aligner or the like. By irradiating with ultraviolet rays immediately after completion, it can be cured in a short time. However,
Problems arise with UV-curable resins, for example, there is a light-blocking area around the color filter, and under this area, because UV light is not irradiated, an uncured part remains and the adhesive strength decreases. I can't lick.

In the case of an X-ray curing type resin, a pixel portion of a display element is aligned with a color filter, and the X-ray is irradiated to the resin, whereby the resin below the light shielding region is also cured. be able to. However, there are problems such as the deterioration of the dye of the color filter due to the irradiation of X-rays, which has an adverse effect, and that the handling of the apparatus requires sufficient care. In addition, there is a problem in that with the increase in the size of the display, it is necessary to increase the size of a heating furnace for curing and a manufacturing apparatus such as an ultraviolet ray / X-ray irradiation apparatus.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and has been made without increasing the size of the manufacturing apparatus even when the color display device is enlarged.
An object of the present invention is to provide a method of manufacturing a color display device in which the alignment accuracy of a color filter is high, the adhesion strength of the color filter is high, and the color filter is not deteriorated.

[0008]

According to the present invention, a color filter (for example, an interference type color filter, a pigment dispersion type color filter, a gelatin type color filter) is formed on a liquid crystal display device via a pressure-sensitive adhesive composition. Filter), align the liquid crystal display element with the color filter, apply a predetermined pressure to break the microcapsules, and heat and ultraviolet rays / X-rays with the contained initiator. The adhesive composition can be cured without irradiating the adhesive, the alignment can be accurately performed, and the uncured portion of the adhesive composition does not occur, and furthermore, good adhesion can be achieved without deteriorating the pigment of the color filter. It can be performed.

According to the present invention, a liquid crystal display element and a color filter are prepared by pressure-sensitive curing in which microcapsules containing a reaction initiator are dispersed in a radical polymerizable composition comprising an acrylic monomer in which a polymerization accelerator is dissolved. Provided is a color display device which is bonded by pressurizing a mold bonding composition.

[0010]

The color filter is for converting a colorless image generated from a liquid crystal display device into a color image, and includes an interference type, a pigment dispersion type and a gelatin type color filter. Can be used.

The above-mentioned pressure-sensitive curable adhesive composition is for disposing a color filter at a predetermined position of a liquid crystal display element and integrally bonding the liquid crystal display element and the color filter with high alignment accuracy. Microcapsules containing a reaction initiator are dispersed in a radically polymerizable composition in which a polymerization accelerator is dissolved.

The method for producing the reaction initiator-containing microcapsules used herein is, for example, as follows. A composition obtained by blending a photosensitizer, an ultraviolet ray blocking agent and a reaction initiator in a hydrophobic ultraviolet-polymerizable monomer is emulsified and dispersed in an aqueous solution containing a water-soluble polymer to produce colloid particles,
By irradiating ultraviolet rays to cure only the surface of the colloidal particles, the core substance is a hydrophobic ultraviolet-polymerizable monomer or oligomer in which a reaction initiator is dissolved, and the wall film is formed of a polymer film of a hydrophobic ultraviolet-polymerizable monomer. Microcapsules can be manufactured. The hydrophobic UV-polymerizable monomer is preferably an acrylic monomer. For example, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, 2,2′-bis (4 -Methacryloxypropoxyoxy) propane, 2,2′-bis (4-acryloxypropoxyphenyl) propane, and the like, but are not limited thereto, and epoxy methacrylate, epoxy acrylate, Combinations of urethane methacrylate, urethane acrylate and unsaturated polyester with the above monomers can also be used. As the photosensitizer, those used in general ultraviolet curing are used, and examples thereof include benzoin ethyl ether, xanthone, thioxanthone, and acetophenone.
The addition amount is in the range of 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic monomer or oligomer. Examples of the ultraviolet absorber include Pt-butylphenyl salicylate, 2-hydroxy-4-methoxybenzophenone, and the like. The amount of the ultraviolet absorber is 0.1 to 20 parts by weight based on 100 parts by weight of the (meth) acrylate monomer or oligomer. It is. The amount of addition is adjusted by its ability to block ultraviolet rays (transmittance), and the thickness of the capsule wall film depends on the amount of addition,
It varies depending on the UV illuminance and irradiation time.

The reaction initiator contained in the microcapsules is preferably a hydroperoxide, and examples thereof include cumene hydroperoxide, P-menthane hydroperoxide, and diisopropylbenzene hydroperoxide. The amount of addition is 1 to 10% by weight based on the hydrophobic UV-polymerizable monomer.
Examples of the water-soluble polymer include gum arabic, gelatin, kaizen, polyvinylpyrrolidone, and the like, which have a function as an emulsifying dispersant, and further have a microcapsule formed by adding sodium alginate as a stabilizer in an aqueous solution. It is preferable to prevent suspicion. The amount of the aqueous polymer added is preferably in the range of 1 to 10% by weight based on water.
The addition amount of sodium alginate is 1 to 10 with respect to water.
A range of weight% is preferred.

When a pressure-sensitive adhesive composition is prepared, the amount of the obtained microcapsules is preferably determined appropriately according to the amount of the reaction initiator contained in the microcapsules. System monomer 10
It is 0.5 to 10 parts by weight (1 to 10% by weight as the amount of the reaction initiator) based on 0 parts by weight.

The polymerization accelerator accelerates the initiation reaction of the encapsulated reaction initiator and / or the polymerization reaction of the radically polymerizable composition which occurs when the pressure-sensitive adhesive composition is pressurized to break the microcapsules. For example, N, N-dimethylaniline, tetrahydroquinoline, triethylamine, ethylenethiourea and the like can be mentioned. The addition amount is 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic monomer.

The radical polymerizable composition preferably has radical polymerizability, has good compatibility with the hydrophobic ultraviolet polymerizable monomer encapsulated in the microcapsule, and has a strong adhesive force. Is preferable, and particularly the same as the acrylic monomer used for producing microcapsules is preferable.

The bonding is performed by arranging the liquid crystal display element and the color filter at predetermined positions with the pressure-sensitive adhesive composition interposed therebetween, and pressing the pressure-sensitive adhesive to cure the pressure-sensitive adhesive composition at a low temperature. be able to. Pressurization is usually 1 to 1
It is performed at 0 kg / cm ² . The temperature is usually 20-40 ° C
It is done in.

[0019]

In the present invention, the mixing of the radical polymerizable composition in which the polymerization accelerator is dissolved and the reaction initiator is suppressed until the microcapsules constituting the pressure-sensitive curable adhesive composition are broken by pressure. Accordingly, the pressure-sensitive curable adhesive composition is not cured during the operation of interposing the pressure-sensitive curable adhesive composition between the liquid crystal display element and the color filter. Further, by applying pressure, the microcapsules are broken, and the reaction initiator contained in the microcapsules is mixed with the radical polymerizable composition in which the polymerization accelerator is dissolved, and pressure-sensitive curing is performed at a relatively low temperature. The mold adhesive composition cures, and the liquid crystal display element and the color filter adhere.

[0020]

The present invention will be described below with reference to examples. FIG.
In FIG. 2, the color filter 1 has a chromium light-shielding region 3 formed around the delta pattern 2 and alignment marks 4 for alignment, and the alignment with the alignment marks 7 of the liquid crystal display element 5 in FIG. Used for (alignment). In the liquid crystal display element 5, an alignment mark 7 for positioning with the color filter 1 is formed outside the effective range of the light receiving section 6. Next, FIG. 3 shows a state where the liquid crystal display element 5 and the color filter 1 are bonded.

The pressure-sensitive curable adhesive composition 8 is dropped on the light-receiving portion of the liquid crystal display element 5, and then maintained at a pressure of 1 kgf / cm ² or more for about 100 seconds while aligning these alignment marks (4 and 7). And cure.

The pressure-sensitive adhesive compositions used in the examples were prepared according to the following formula. First, methyl methacrylate and 2-hydroxyethyl methacrylate (70/30:
(Weight ratio) 10 parts by weight, 1 part by weight of 2,2-dimethoxy-2-phenylacetophenone, 0.5 part by weight of 2-hydroxy-4-methoxybenzophenone, 0.5 part by weight of cumene hydroperoxide were added to 5 g of polyvinyl alcohol. Was dispersed in 500 cc water in which water was dissolved, and while being stirred so that the particle size became 10 μm or less, ultraviolet irradiation was performed with a 300-w high-pressure mercury lamp for 5 minutes, and methyl methacrylate and 2
-Producing spherical microcapsules containing hydroxyethyl methacrylate and Kumei hydroperoxide.

Next, 6 g of the above microcapsules were dispersed in a radical polymerizable composition composed of 4 g of ethylene thiourea, 70 g of methyl methacrylate and 70 g of 2-hydroxyethyl methacrylate (70/30 weight ratio). This allows
A pressure-sensitive adhesive composition was obtained.

As shown in Table 1, the evaluation of the adhesion performance of the color filter thus bonded was good.

[0025]

[Table 1]

Comparative Examples 1 to 3 In the test samples whose curing methods were different from those of the present invention, color deterioration was observed in Comparative Example 1, peeling was observed in Comparative Example 2, and poor alignment accuracy was observed in Comparative Example 3, as shown in Table 1. Was done.

[0027]

According to the present invention, in a liquid crystal display device and a color filter, the alignment accuracy on a large substrate can be improved, and the adhesive composition can be surely cured even in the lower part of the light shielding region. As well,
By providing transparency and light resistance, it is possible to realize good adhesion without deterioration of the dye, and thus to extend the life of the color display device itself.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a color filter used in an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a liquid crystal display element used in an embodiment of the present invention.

FIG. 3 is an explanatory view of a color display device manufactured by bonding a color filter to a liquid crystal display in the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Color filter 2 Delta pattern 3 Shield area 4 Alignment mark 5 Liquid crystal display element 6 Light receiving part 7 Alignment mark 8 Resin 9 Glass plate 10 Liquid crystal 11 ITO

Continuation of front page (56) References JP-A-1-193314 (JP, A) JP-A-59-44006 (JP, A) JP-A-59-44008 (JP, A) JP-A-4-201478 (JP) JP-A-55-108778 (JP, A) JP-A-2-281755 (JP, A) JP-A-55-176578 (JP, U) JP-A-57-142855 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) G09F 9/00 G09F 9/35 C09J 4/02-4/06 C09J 5/00 C09J 11/00-11/08

Claims (5)

(57) [Claims] 1. A pressure-sensitive adhesive composition comprising a liquid crystal display element and a color filter, wherein a microcapsule containing a reaction initiator is dispersed in a radical polymerizable composition comprising an acrylic monomer in which a polymerization accelerator is dissolved. A color display device that is bonded by applying pressure. 2. The color display device according to claim 1, wherein the microcapsules contain a hydrophobic UV-polymerizable monomer in which a reaction initiator is dissolved. 3. The color display device according to claim 2, wherein the hydrophobic ultraviolet-polymerizable monomer is an acrylic monomer. 4. The color display device according to claim 1, wherein the reaction initiator is a hydroperoxide compound. 5. The color display device according to claim 1, wherein the polymerization accelerator is N, N-dimethylaniline, tetrahydroquinoline, triethylamine, ethylenethiourea, or the like.