JPS6151024A - Photocurable sealing resin composition - Google Patents

Abstract

PURPOSE:To titled composition which has a strong bonding force and can form a high-quality liquid-crystal cell, containing a resin having epoxy groups and a main chain skeleton of a butadiene polymer, an epoxly resin, a (meth)acrylate ester and a photosensitive aromatic onium salt. CONSTITUTION:A resin composition containing (A) a resin having a butadiene homopolymer or copolymer as a main chain skeleton and having at least 1.5 epoxy groups per molecule on the average at molecular ends and/or side chains, (B) at least one epoxy resin selected from among aliphatic, bisphenol A, bisphenol F, novolak, and hydrogenated bisphenol A epoxy resins, (C) an acrylate and/or methacrylate ester, and (D) a photosensitive aromatic onium salt.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a photocurable resin composition for sealing. More specifically, during the manufacturing of liquid crystal cells, the two substrates are joined together, the cell periphery is sealed at the same time, and the liquid crystal injection port formed for injecting the liquid crystal is sealed tightly after the liquid crystal is injected. The present invention relates to a photocurable resin composition for sealing which has excellent adhesive properties, sealing properties, cold/heat cycle resistance, and liquid crystal suitability. □ [Prior Art] Generally, liquid crystal cells used in display devices are made by bonding two glass or plastic substrates together with a peripheral sealant such as organic epoxy resin or inorganic frit glass, with a predetermined gap between them. It is formed by holding and joining. In resin! A typical example of a sealing method is to use screen printing to apply a sealant to one substrate to form the cell periphery, attach another substrate with a spacer in between, and then harden the sealant. There is. At this time, a small hole is made in a part of the cell as an injection port to inject the liquid crystal after the cell is formed, and after the liquid crystal is injected into the cell, it is sealed with a sealant to maintain airtightness. I have to. Conventionally, one-liquid or two-liquid epoxy thermosetting resin compositions have been used as these peripheral sealants. For example, as such prior art document, Japanese Patent Publication No. 58-2206
Although Publication No. 0 has been praised, since the compositions of this sealant were eluted into the liquid crystal, abnormalities in liquid crystal alignment and deterioration of the liquid crystal frequently occurred. In addition, since the resin curing process is performed at high temperatures and over a long period of time, there may be problems with quality control such as minute cracks caused by curing shrinkage in the sealant or substrate material, or productivity problems such as difficulty in line production. There remained a big problem. On the other hand, in the case of a liquid crystal injection port sealant, it must be cured and bonded in contact with the liquid crystal, and cannot be heated at high temperatures to prevent deterioration of the liquid crystal. Therefore, curing of the sealant takes a long time at low temperature, which causes alignment abnormalities and poor curing due to elution of the sealant composition into the liquid crystal, resulting in problems in terms of quality, quality control, and production. It was becoming a big problem. In order to solve these problems, various applications of photocurable sealants have been studied. These photocurable resin systems are made by irradiating a photoradical initiator with ultraviolet rays in the presence of an unsaturated double bond-containing monomer and using a photoradical initiator and an aromatic onium salt as a heavy initiator to place radicals. The resin is cationically polymerized by ultraviolet irradiation to form a photocationic type. Japanese Patent Application Laid-Open No. 153-1989 as a prior art document of the photo-radical type
No. 651 and JP-A No. 58-44420, but in the polymerization of these acrylic or methacrylic monomers, internal stress is generated due to volume reduction during polymerization, resulting in insufficient adhesion. When external pressure is applied to it, the resin sealing part peels off, causing the liquid crystal inside to protrude to the outside. Moreover, the bond between the glass and the sealant broke down due to cold and heat cycling, which caused problems such as liquid crystal in the cell leaking. Also,
Even if the cured product has sufficient adhesive strength in common with peripheral sealants and injection port sealants, air may enter the cell through the cured resin due to the lack of barrier properties, which is one of the sealing properties. There were problems such as air bubbles being generated in the liquid crystal cell. On the other hand, as a prior art document on photocationic phoenix,
No. 14277, Special Publication No. 52-14278, Special Publication No. 14278
-14297, etc., and these include epoxy resins that can be polymerized into a high molecular weight state as one component of the composition, but generally used resin golds collectively called epoxy resins. The present inventors have confirmed that the composition cannot be cured by adding an aromatic onium salt. For example, glycidylamine plastic epoxy resins such as polyethylene glycol diglycidyl ether, known as flexible epoxy resin, and p-xylylenediamine tetraglycidyl, amine, known as heat-resistant epoxy resin, can be cured using other curing methods, such as acid anhydride. Alternatively, a cured product can be obtained by blending an epoxy curing agent such as dicyandiamide and heating, but no cured product can be obtained even if an aromatic onium salt is blended and irradiated with ultraviolet rays. Furthermore, when the composition described in the examples of the prior art document is used as a liquid crystal injection hole sealant, the cured product has a low glass transition point Tg and the barrier properties are insufficient, or the cured product has poor cold and heat cycle resistance. was low, and bubbles were generated inside the liquid crystal cell. Furthermore, even in these compositions that do not cause visual abnormalities, the liquid crystal driving current value increases over time. Furthermore, with this photocation type, the hardening progresses slower than with the photoradical type when exposed to ultraviolet rays, and when this composition is used as a liquid crystal injection hole sealant, the internal curing property is poor and the contact interface with the liquid crystal is hardened. This has the disadvantage that elution into the liquid crystal occurs, disturbing the liquid crystal alignment, and increasing the liquid crystal driving current value. For this reason, there are no photocurable resin compositions that have the performance as a peripheral sealant, and photocurable compositions that can be used as injection port sealants have extremely low performance levels such as 6D, There is a strong desire to develop a photocurable sealant that has quick curing properties, excellent adhesion, thermal cycleability, sealing properties such as gas barrier properties, and suitability for liquid crystals such as low elution properties. Ta. [Problems to be Solved by the Invention] The present invention solves the drawbacks of the conventional thermosetting type, photocuring type, peripheral area, injection port, and sealing agent described above, and has strong adhesive strength. Provided is a photocurable resin composition for sealing, which enables the production of high-quality liquid crystal cells having excellent sealing and sealing properties and cold/heat cycle resistance in a simpler and shorter time than conventional production processes. It's about doing. [Means for Solving the Problems] As a result of intensive studies in view of the above-mentioned points, the present inventors have developed a system that uses an aromatic onium salt as a cationic polymerization initiator for an epoxy resin. The main chain skeleton is a butadiene homopolymer or a butadiene copolymer that does not affect the liquid crystal when fused with the liquid crystal, and the epoxy group at the molecular terminal and/or side chain is at least 1.5 on average per molecule. By finding resins and specific epoxy resins that have more than 100% of the epoxy resin, and at the same time adding an acrylic ester and/or methacrylic ester polymer that polymerizes with radicals generated by photolysis of aromatic onium salts, we have succeeded in comparing photo-radical play. It has good adhesion,
It has also been found that a composition can be obtained that has a faster curing speed and better internal curability than that of photocationic porcelain. Furthermore, it was discovered that a cured product obtained by light irradiation of the same composition has few eluted components and has good moisture resistance and heat resistance over time in a long-term liquid crystal cell abuse test, leading to the completion of the present invention. That is, the present invention provides - (A) having a main chain skeleton of a butadiene homopolymer or a butadiene copolymer, and having an average of at least 1.5 or more epoxy groups per molecule at the molecular terminals and/or side chains; Resin 0 One or more epoxy resins selected from the group consisting of epoxy resins, bis-7 ether Afi epoxy resins, bisphenol Fi epoxy resins, novolac-like epoxy resins, and hydrogenated bisphenol Afi epoxy resins. Resin 0 Acrylic ester and/or methacrylic ester 0 A photocurable resin composition for sealing that is rapidly cured by irradiation with active energy rays and is characterized by containing a photosensitive aromatic onium salt as an essential component. It is a thing. The present invention will be explained in detail in 1 below. A resin whose main chain skeleton is a butadiene homopolymer or butadiene copolymer of component (A) used in the present invention, and which has an average of at least 1.5 or more epoxy groups per molecule at the molecular terminal and/or side chain. a) Epoxidized polybutadiene obtained by treating a butadiene photopolymer or a butadiene copolymer (hereinafter abbreviated as butadiene-based polymer) with an organic peroxide to epoxidize the double bonds in the structural units ~ For example, 1. Epoxidized polybutadiene BF-1000, BF obtained by treating 2-polybutadiene with peracetic acid
-, 2,000 (Adeka Argus ■ trade name). b) Terminal epoxidized butashev-based polymers with epoxy groups introduced at the molecular ends by telomerization during polymerization, for example, butadiene alone or copolymerizable with butadiene, pentadiene, hexadiene, and isopres □ obtained by living anionic polymerization. A low temperature reaction intermediate (living polymer) is prepared by reacting a mixture of other monomers such as sodium dilithium in the presence of an alkali metal catalyst such as sodium dilithium. Care mortar”
z-(CHt) Ma・Yo, R4□5E几 Atom, m is 0
A halogenated alkylene oxide represented by the above formula, for example,
A terminally epoxidized butadiene-based polymer obtained by treating with epichlorohydrin and introducing an epoxy group at the end of the polymer chain. C) Polybutadiene-modified epoxy resin obtained by esterifying a butadiene-based polymer having a carboxyl group in the molecule and an epoxy resin, for example, IVf Kaisho 5
Nippon Soda ■ brand name epoxy yEPB-12, epoxy BPB-13 obtained by the method described in Publication No. 5-137125,
The same EPB-14, the same BPB-17, the same BPB-25, the same RPB-27, the same EPB-42, the same EPB-44; Tobu Kasei brand name Evo) - YR-102, YR-
207; ACR Epoxy R-1309, ACR Epoxy X-1363, ACR Epoxy X-1374, etc. manufactured by NCR Co., Ltd. can be used. The above-mentioned various butadiene-based polymers having 1, 5 or more epoxy groups in one molecule (2) component can be used alone or in a mixed system of 28 or more. This one
The amount of the butadiene-based polymer (A) component having 1.5 or more epoxy groups in the molecule is 10 to 70 parts by weight, preferably 20 to 70 parts by weight, based on the total amount of the 4 and 0 components. It is 60 parts by weight. If the amount of component (A) exceeds the above-mentioned maximum limit of 70 parts by weight, the amount of flexible component in the composition will be excessive, and the Tg of the cured product will drop significantly, resulting in insufficient barrier properties. On the other hand, if the amount is less than the above-mentioned minimum limit of 10 parts by weight, it is not preferable because the stress relaxation component decreases, causing cracks in the cured product during curing9 and poor adhesion at the adherend interface. The zero-component epoxy resin used in the present invention is i) alicyclic epoxy resin, such as Union Carbide Company (U, C, C) trade names ERL-4221, 4289, 4206, and 423.
4, 4205, 4299, UVR-6100: Ciba Gaiki's product names CY-179, CY-178, CY-180, CY-175; Chisso ■ product names CX-221, CX-289, Same c.
x-206, CX-301, CX-ai3; Daicel ■ trade name Celoxide-202111) bisphenol Afi epoxy resin, for example, oily shell epoxy (Keg brand name Epicote 827, 828, 834, Daicel ■) 836, 1001, 1004, 100
7; Ciba Geigy's product name Araldite CY252, Araldite C
Y250, CY260, CY280, 6071,
6084, 6097; Dow Chemical Company's product names DER330, 331, 337, 661, 664; Dainippon Ink Chemical Company's product names Epicron 800, 1010, 1000, 3010; Tobu Kasei -) YD-128, YD-134, YD-8125 iii) Bisphenol Fm resins, such as oil-based shell epoxy■ Trade name Epicote 807; Tobu Kasei (trade name (2) Epo ) -) YDF-17
0; Dainippon Ink Chemical 4 trade name Epicron 830, same 1 ■) Novolak type epoxy resin, for example, oil-based shell epoxy ■ trade name Epicort 1
52, 154; Dow Chemical Company's product name DEN-431, 438;
439; Ciba Geigy product name BPN-1138, ECN-1
235; Trade names of Dainippon Ink Chemical ■ Epiclon N-740, Epiclon N-680, Epiclon N-695, Epiclon N-565, Epiclon N-57
7V) Water R-added bisphenol A diglycidyl ether resin, for example, Adekal Resin EP-40 manufactured by Mudenka Kogyo ■
80, etc. can be used. These various zero-component epoxy resins may be used alone or in a mixed system of two or more. The amount of this epoxy resin used is (A
) and 0 component so that the amount is 90 to 30% by weight, preferably 80 to 40% by weight. Epoxy resin provides a hardened product with a high Tg,
In addition, when curing with aromatic onium salts, the curing properties are particularly excellent and curing takes place in a short time, but the above usage range is set because the cured product has disadvantages such as brittleness and poor cold and heat resistance @ impact resistance. be done. The zero-component acrylic ester or methacrylic ester monomer used in the present invention, diacrylate or dimethacrylate of ethylene glycol, diethylene glycol, triethylene glycol (hereinafter, acrylate or methacrylate is abbreviated as (meth)acrylate), Polypropylene glycol di(meth)
Acrylate, di(meth)acrylate of 1,3-butylene glycol, glycidyl(meth)acrylate, butoxy(meth)acrylate, 2-hydroxyethyl(
meth)acrylate, 2-hydroxypropyl(meth)
Acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexaacrylate, methyl(meth)acrylate, ethyl(meth)acrylate, butyl(meth)acrylate, 2-ethylexyl(meth)acrylate, lauryl(meth)acrylate, Compounds having one or more acryloyl or methacryloyl groups in the molecule such as stearyl (meth)acrylate, allyl (meth)acrylate, cyclohexyl (meth)acrylate, and butoxyethyl (meth)acrylate can be used. These various acrylic ester and methacrylic ester monomers of component (A) may be used alone, or two or more types may be used in combination. The amount of the zero component used is 5 to 50 parts by weight, preferably 15 to 40 parts by weight, based on 100 parts by weight of the total amount of (A) and the zero component. If the amount exceeds 50 parts by weight of the above-mentioned maximum amount of component 0, the cured product will shrink significantly during photocuring, resulting in a decrease in adhesive strength. On the other hand, if the amount is less than the above-mentioned minimum limit of 5 parts by weight, curing due to polymerization and crosslinking of acrylic double bonds will be insufficient, making it impossible to obtain sufficient curing properties within the irradiation time. In addition, the capture of initiator decomposition radicals becomes insufficient and the amount of components eluted from the cured product increases. As the photosensitive aromatic onium salt of component 0 used in the present invention, aromatic onium salts of group ■a elements shown in Japanese Patent Publication No. 52-14277,
Aromatic onium salts of Group A elements shown in Japanese Patent Publication No. 8 and aromatic onium salts of Group Va elements shown in Japanese Patent Publication No. 14279/1988 can be used. More specifically, for example, triphenylphenacylphosphonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, etc. can be used. These onium salts release Lewis acids when irradiated with active energy rays such as ultraviolet rays, which initiate cationic polymerization of epoxy, and simultaneously generated radicals initiate radical polymerization of acrylic esters or methacrylic esters. The amount of the photosensitive aromatic onium salt used is 0.25 to 10 parts by weight, preferably 2 to 5 M parts, based on 100 parts by weight of the total amount of (A) and component 0. If the amount of onium salt added is less than 0.25 parts by weight, curing by active energy rays will be insufficient, and the cured product will have a low Tg and insufficient barrier properties. Furthermore, low molecular weight substances in the cured product are eluted into the liquid crystal and cause poor alignment of the liquid crystal. On the other hand, if the amount added is more than 10 parts by weight at the upper limit of the range, the decomposition products of the aromatic onium salt gradually dissolve into the liquid crystal, which tends to increase the driving current value of the liquid crystal. (A): If the above-mentioned aromatic onium salt is insufficiently compatible with the mixture of components 0 and 0, the onium salt can be used by dissolving it in a suitable solvent, such as acetonitrile, propylene carbonate, or cellosolve.The present invention A solvent can be used in the resin composition for the purpose of improving the workability of screen printing, especially when used as a liquid crystal cell peripheral sealant. Various solvents belonging to hydrocarbons, ethers, aliphatic or aromatic hydrocarbons, or chlorinated hydrocarbons that do not disturb the emulsion of the screen are used. The resin composition according to the present invention contains a reactive diluent having one or more epoxy groups in its molecule to reduce the viscosity of the composition or adjust the reactivity. Examples of the reactive diluent mentioned here include butyl glycidyl ether, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, p-butylphenyl glycidyl ether, glycerin glycidyl ether, Neopentyl glycol diglycidyl ether, etc. can be used.The amount of the reactive diluent to be used is within a range that does not impair the adhesiveness and liquid crystal suitability for the purpose of the present invention, but is preferably within a range. The amount is within 20 parts by weight based on 100 parts by weight of the total amount of (A) and component 0. The resin composition according to the present invention may also be added with various modifications as required for modification of physical properties or use. For example, a granular or acicular spacer to maintain a spatial distance between liquid crystal cells; fillers such as silica and glass beads; and fillers to improve adhesion and moisture resistance. Silicone-based or titanate-based coupling agents; other coupling agents; textotropic property-imparting agents such as Aerosil and bentone for imparting screen printability;
Leveling agents such as Florade; aluminum hydroxide;
Extender pigments such as barium hydroxide; and improved polymer substances such as petroleum resins, rosins, nylons, and acrylic resins can also be blended. In order to cure the resin composition according to the present invention, a wavelength of 200
Ultraviolet light of ~400 nm is effective. Examples of this radiation source include a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, and a metal halide lamp. Other active energy rays that can be used for curing include visible light, X@, and electron beams. Furthermore, although the present composition is sufficiently cured by irradiation with active energy rays and exhibits properties that meet the intended purpose, even better properties can be obtained by releasing the composition into a heating chamber after irradiation. An example of this temperature range is 50 to 80°C for 2 to 20 hours. In addition, the photocurable resin composition for sealing according to the present invention has excellent adhesiveness, cold and heat cycle resistance, flexibility, etc., and is fast curing, so it can be used as a sealant for liquid crystal cells. It can also be used as an adhesive for other light-transmitting materials such as glass and plastic. For example, camera lenses 1, eyeglass lenses, other optical lenses, lenses, stereo dials, decorative laminated glass, automotive laminated glass, heat-insulating laminated glass, advertising films,
Adhesion of printed typesetting boards, etc., connection or temporary fixing of die bonding lead wires, temporary fixing of chip components mounted on printed circuit boards, protective coating of electronic circuits, surface protection of parts,
It can also be applied to adhesives related to laser discs, resins for plastic molding, sealing of small parts, botting, and adhesion of coil terminals, and is limited to the use of photocurable resin compositions for sealing liquid crystal cells. It is not something that can be done. , −
[Function] The starting mechanism of aromatic onium salts using photocationic initiators is as follows. For example, in the case of sulfonium salts,
. hμ Ar, S"X--1 → (ArsS "X-)"2Ar
” -nAr 'Ar "Ar
"+ZH-÷ArI-I+Z" The aromatic onium salt decomposes upon irradiation with light and releases a protonic acid having cationic and ionic polymerization abilities, as indicated by HX. However, in cationic polymerization in a solvent-free system such as the composition of the present invention, since this protonic acid diffuses as a polymerization terminal, radicals that diffuse at the polymerization terminal simply by electron transfer are generated. The reaction rate was slow compared to polymerization. For this reason, as a liquid crystal injection port sealant, which is one of the main uses of the composition of the present invention, in some cases, it is necessary to build up a layer to a thickness of about 1 mm and take at most 1 to 2 days to completely cure it. Therefore, improvements were required. W and C found that the radicals generated in the protonic acid production process shown in both formulas initiate radical polymerization of acrylic or methacrylic double bonds. Perkins (Journal of Radia
tion Curing, 8. (1:l. 16, (1981) and U.S. Pat. No. 4,156,03
It is shown in No.5. The inventors of the present invention have examined such a composite system of epoxy photocationic polymerization and acrylic radical polymerization, and although improvements in curability and internal curability in thick film curing have been recognized, US Pat. It has been found that not all of the "polymerizable epoxy resin" listed as an essential component in the claims of No. It's here. Furthermore, it is clear from the inventors' study on the barrier properties of the cured product and the study on the components eluted from the cured product that not all of the compositions exemplified in these documents are suitable as liquid crystal cell sealants. It has become. On the other hand, the effectiveness of the addition of acrylic and/or methacrylic yarns is that in addition to improving the curing properties and internal curing properties mentioned above, it also reduces the components eluted from the cured product, resulting in good moisture resistance and heat resistance in the abuse test of liquid crystal cells. This is remarkable because it shows time-lapse characteristics. The present inventors investigated the elution behavior of various epoxy photocation-based cured products and the temporal changes in the liquid crystal cell wind current value in a liquid crystal cell abuse test. If you select a raw material resin that does not have
It was found that the increase in liquid crystal cell driving current value over time depends on the amount of onium salt used as an initiator and its photodecomposition product. It was also found that among these compounds, low-molecular aromatic compounds have a particularly large effect on liquid crystals. According to the results of GPC (gel permeability chromatography) analysis of the eluted components by the present inventors, it was found that the amount of initiator added and the peak height of the GPCUV detector were in a linear relationship of υ in the upper right corner. It can be seen that if the amount of initiator added is reduced, the components released from the bath are reduced. However, a decrease in the amount of initiator added is not preferred since it results in poor curability and poor adhesive strength. Acrylic and/- to epoxy photocationic system! or methacrylic monomer, as shown in the above-mentioned initiation mechanism formula of aromatic onium salt (Ar, S X-:l, Ar
It was thought that the effect was to capture radicals such as ', Zo, etc. and fix them at the terminals of acrylic polymerization. From this point of view, the amount of eluted components due to the addition of acrylic and/or methacrylic monomers was investigated from the GPCUV detector peak height, and the results shown in FIG. 1 were obtained. From the same figure, it can be seen that the eluted components decrease due to the addition of the acrylic monomer. Furthermore, since the plot is also below the theoretical line due to acrylic monomer dilution shown in the same figure, it is clear that this decrease in eluted components is due to the effect of trapping initiator decomposition radicals due to the addition of acrylic monomer. The radicals captured here generate low-molecular aromatic compounds by stopping recombination, so if such 7mer addition is not performed, they will elute into the liquid crystal over time and affect the performance of the liquid crystal cell. It is clear that it reduces [Example] Next, the present invention will be specifically explained with reference to Examples and Comparative Examples, but the present invention is not limited only to these Examples. Note that parts and percentages in fat are parts by weight and percentages by weight. Example 1 Molecular weight approximately 1.50 produced by anion living method
Epoxidized 1,2-polybutadiene BF-1000 with an epoxy oxirane content of 7.7% corresponding to the component (A) of the present invention obtained by treating 1,2-polybutadiene with peracetic acid (Adeka Argus) ■Product name) 50
Alicyclic epoxy resin corresponding to part and 0 component E)! ,L-
4221 (trade name of Company U, C, C) 50 parts 0 Glycidyl methacrylate 20 parts gold Mix well. Next, component (D), triphenylsulfonium hexafluoroantiheptanoate (50% fluoropylene carbonate)
Solution) 4 parts, Aerosil-11 = 380 (trade name of Nippon Aerosil ■) 2 parts were added and kneaded well to obtain the sealing photocurable resin composition [1]t of the present invention for sealing liquid crystal injection holes.
-I got it. Example 2 46 parts of sodium dispersion was added to 5.000 parts of tetrahydrofuran in which 46 parts of 1.2-diphenylbenzene was dissolved, and the temperature was maintained at -60'C.
The solution was added dropwise over a period of time, and after completion of the addition, it was kept at -60°C for 1 hour. Next, 185 parts of picrohydrin was added dropwise to this and mixed well. After washing this product twice with an equal volume of water, tetrahydrofuran was distilled off under reduced pressure to obtain a terminal epoxy oxirane with a number average molecular weight of 11,370 and an epoxy oxirane with an oxygen content of 2.01%, which corresponds to component (A) in the present invention. Polybutadiene was obtained. next,
30 parts of the terminal epoxidized polybutadiene and alicyclic epoxy resin HR, L-4299 (U,
C0C, Co., Ltd. trade name) 70 parts, component 0 trimethylolpropane triacrylate 35 parts, component 0 triphenylphenacylphosphonium tetrafluoroborate (propylene carbonate 50X solution) 5 parts, epoxy group-containing silane coupling agent KBM -403 (Shin-Etsu Silicone (trade name of (2)) 1.5 parts, Aerosilite 380
Two parts were thoroughly kneaded to obtain a sealing photocurable resin composition [2] of the present invention for sealing liquid crystal injection holes. Example 3 Polybutadiene-modified epoxy resin obtained by reacting an epoxy resin with 1,2-polybutadiene having a carboxyl group at the molecular end produced by an anion living method Nisso Epoxy EPB-27 (Nippon Soda ■ trade name) 20 parts, EOC which is a novolac type epoxy resin
N-103 (Nippon Kajimi brand name), 70 parts of YD8125 (Tobu Kasei brand name), and 10 parts of diethylene glycol diacrylate are thoroughly mixed. Then, 10 parts of tri□phenylsulfonium hexafluoroantimonate (50% solution in fluoropylene carbonate) and Aerosil+3
20 Add 12 parts and mix, mix well with three paint rollers, then use a spacer with a diameter of 5 μm and a length of 15
~30 μm glass single fiber (manufactured by Chuyu Optical Glass Manufacturing Co., Ltd.) 2
A photocurable resin composition for sealing [3] for sealing the periphery of a liquid crystal cell was obtained by mixing the two parts. Example 4 HycarCTBN13, a butadiene-acrylonitrile copolymer with a carboxyl group at the end of the molecule
00X13 and 550 parts of bisphenol 2°C type epoxy resin Epotote YD-812 were placed in a separable flask equipped with a stirrer, reflux condenser, nitrogen blowing tube, and thermometer, and heated at 130°C with stirring under a nitrogen atmosphere. After reacting for 4 hours, a polybutadiene-modified epoxy resin having an acid value of 0.6 was obtained. Next, 50 parts of the polybutadiene-modified epoxy resin, 50 parts of bisphenol F type epoxy resin Epicote 807 (trade name of Yuka Shell Epoxy ■), and 5 parts of Gibe/taerythritol hexaacrylate were added and mixed well.
Then, 8 parts of triphenylphenacylphosphonium tetraborate (50% propylene carbonate solution), KBM
-4031 parts and Aerosil=ll=380 14
After mixing well with three paint rollers, 3 parts of spacer single glass fibers (described above) were mixed to obtain a sealing photocurable resin composition [4] for sealing the periphery of a liquid crystal cell. . Example 5 Epoxidation of epoxy oxirane with oxygen content of 7.7% 1,
2-Polybutadiene BF-100,050 parts, alicyclic epoxy resin ERL-429,950 parts, trimethylolpropane triacrylate 30 parts, triphenylphosphonium hexafluoroantiheptanoate (50% solution in propylene carbonate) 6 parts, and Aerosil 4138,014 parts After thoroughly kneading with three paint rollers, 4 parts of spacer single glass fibers (described above) were mixed to obtain a sealing photocurable resin composition [5] for sealing the periphery of a liquid crystal cell. Example 6 Epoxidation of epoxyoxirane with oxygen content of 7.7% 1,
2-Polybutadiene BP-100,050 parts, alicyclic epoxy resin E-L-422,950 parts, triphthylpropane triacrylate 20 parts, and triphenylphosphonium hexafluoroantimonate (50% propylene carbonate solution) 6 parts were mixed and dissolved, and sealed. A wearable photocurable resin composition [6] was obtained. Comparative Example 1 Alicyclic epoxy resin UVR-6100 (
U, C, C company trade name) 60 parts, flexibility imparting epoxy resin UVR-6351 (U, C, C company trade name) 40 parts, and triphenylsulfonium hexafluoroantiheptanoate (propylene carbonate solution 50% ) 8th part, KBM
-4031 parts, Aerosil≠3802 parts were mixed well. This product differs from the scope of the present invention in that it contains 25 parts of glycidyl methacrylate and does not contain an epoxy group-containing Ptadiene-based polymer. A photocurable resin composition [7] for sealing liquid crystal injection holes of the epoxy photocation radical polymerization type was obtained. Comparative Example 2 100 parts of Araldite MY-720 (trade name, Ciba Geigy) made of N,N'-tetraglycidyl p-phenylene diamine and 10 parts of triphenylphenacylphosphonium tetrafluoroborate (50% propylene carbonate solution) were thoroughly mixed. A photocurable resin composition [8] was obtained. Comparative example 3 Epoxidation of epoxy oxirane oxygen content 7.7 X 1
, 2-polybutadiene BF-100,050 parts, alicyclic epoxy resin ERL-422,150 parts, hexafluoroanthi7ane R triphenylsulfonium (propylene carbonate 50% solution) 4 m, equivalent to the system without the acrylic sevenmer of component A0. ) is different from the claims of the present invention: a photocurable resin composition for sealing a liquid crystal injection hole in an epoxy photocationically polymerized glass

[9] was obtained. Comparative Example 4 Bisphenol Afi epoxy resin Epicoat 828 (
100 parts of the novolak type epoxy resin Epicoat 152 (trade name of Yuka Shell Epoxy ■), 50 parts of neopentyl glycol diglycidyl ether Evolite 150ONF (trade name of Kyoeisha Yushi Kagaku Kogyo ■) 50 parts, Aerosil≠380 40
After mixing these parts, the mixture was thoroughly mixed with three paint rollers, and 5 parts of spacer single glass fibers (described above) were mixed to obtain an epoxy resin composition. Furthermore, 50 parts of a polyamide curing agent TOMIDE 4P2500 (trade name of Fuji Kasei Kogyo ■) and 166 parts of 2-ethyl-4-methylimidazol were added to the epoxy resin composition and mixed well to form a thermosetting resin for sealing around the liquid crystal cell. Composition [10] was obtained. Comparative Example 5 A photocurable resin composition for sealing [11] was obtained by mixing and dissolving the same proportions as in Example 6, except that the acrylic monomer trimethylolpropane triacrylate was not blended. [1] obtained in Examples 1 to 5 and Comparative Examples 1 to 4 above
Regarding the curable resin compositions of [5] and [7] to [10], the curing properties of these compositions were first measured by the method described below, and the results are shown in Table 1. In addition, [3], [4], [5], and [10] were printed by screen printing on a glass plate (thickness o, ss mm) that had been subjected to ion diffusion prevention treatment, electrode formation, and orientation treatment using conventional methods. A resin composition was applied in the shape of the outer periphery of the cell, and then the same treated glass plate used earlier was placed on top and pressure bonded. This was cured by irradiating it with ultraviolet rays for a predetermined period of time from a distance of 1QCm using a high-pressure mercury lamp (80 W/cm) while keeping it in the crimped state. (For some samples, after-keying was carried out for 60'CX1 hour after UV irradiation.) Next, liquid crystal was sealed using the vacuum method, ``[1], [2], [7],

The liquid crystal injection hole was sealed using the resin composition [9], and a high-pressure mercury lamp (80
The resin composition was cured by irradiating ultraviolet rays for a predetermined period of time from a distance of 10 amps (W/am) to produce a liquid crystal cell. Next, the sealing properties, high-temperature and high-temperature/high-humidity penetration properties, liquid crystal cell drive current conversion rate, cold/heat cycle resistance, etc. were evaluated for each sample A~ of the liquid crystal cells shown in Table 2 prepared in this manner. A performance test was conducted and the results are shown in Table 2. Measurement of curing properties> The curable resin compositions [1] to [5], [7] to [10] were heated on a JIS-G-3303 tin plate in a K 6 ml (7
) Apply using Doctor 7'Rade, [1] ~ [
5], [7]~

For [9], high pressure mercury lamp (80
W/an) was irradiated with ultraviolet rays for a predetermined period of time from a distance of □1Qan for curing, and for [10], heat curing was performed at 120'C for 6 hours after application. Next, the properties of these cured resin compositions and the lead field hardness of the cured coating films were determined, and furthermore, these 9 foil coatings were measured using a dynamic viscoelasticity measuring machine Rheoviplon DDV-1 [[=EA (manufactured by Toyo Baldwin)] to determine the displacement ±0. .025mm 1 frequency 3
The viscoelasticity was measured at 5 Herz and a heating rate of 2°C/min, and the Tg and molecular weight between crosslinking points were measured. [Effects of the present invention] As shown in Table 1, the photocurable resin compound for sealing obtained by the present invention has better properties compared to the conventional epoxy photocationic resin composition. It also has good curability and high Tg compared to other sealing resins. It also has an extremely long pot life compared to two-component types. In addition, as shown in Table 2, it has extremely excellent adhesion, sealing properties, and cold/heat cycle resistance as a liquid crystal cell peripheral sealant and injection hole sealant, so it can help save labor in the liquid crystal cell manufacturing process. The contribution is clear.

[Brief explanation of drawings]

FIG. 1 shows the high-pressure mercury lamp (8Q W/
Figure 6 shows the relationship between the GPCUV detector peak height of the solvent-eluted component of the photocured product obtained by irradiation with 10a'rI for 7.0 seconds and the amount of photoinitiator added. The dashed-dotted line in the figure is based on the monomer dilution theory elution, in which the dilution level is added to the peak height of the eluted component without the addition of the acrylic monomer in order to take into account the dilution effect of the initiator due to the addition of the acrylic monomer.

Claims (2)

[Claims] (1) A photocurable resin composition for sealing, which contains the following components (A), (B), (C), and (D) as essential components. (A) A resin whose main chain skeleton is a butadiene homopolymer or a butadiene copolymer and which has an average of at least 1.5 epoxy groups per molecule at the molecular terminal and/or side chain (B) Alicyclic epoxy resin , bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolak type epoxy resin, and hydrogenated bisphenol A type epoxy resin (C) acrylic ester/or methacrylate Acid ester (D) photosensitive aromatic onium salt (2) In the blending of components (A), (B), (C), and (D), the blending ratio of components (A) and (B) is 10 to 70 parts by weight of component (A), and 10 to 70 parts by weight of component (B). The components are 90 to 30 parts by weight, and the (C) component is 5 to 50 parts by weight, and the (D) component is 0.2 parts by weight relative to 100 parts by weight of the total amount of components (A) and (B).
The photocurable resin composition for sealing according to claim 1, wherein the amount is 5 to 10 parts by weight.