KR20070080014A - Sealing resin composition - Google Patents

Abstract

Provided is a sealer resin composition which is very excellent in the adhesive strength on a glass substrate after radiation curing and thermal curing process and is useful as a sealer for an LCD device. The sealer resin composition comprises 30-80 wt% of a partial epoxy (meth)acrylate resin as a curing resin; 1-30 wt% of a thermal curing agent; 0.1-4 wt% of a radical photopolymerization initiator; 1-30 wt% of an organic-inorganic hybrid monodisperse polymer particle; and 5-30 wt% of an inorganic filler. Preferably the organic-inorganic hybrid monodisperse polymer particle is a copolymer obtained by the radical polymerization of an alkoxysilane (meth)acrylate monomer and at least one kind of radical polymerizable monomer, and has an alkoxysilane group on surface.

Description

Sealing resin composition {Sealing Resin Composition}

The present invention relates to a sealing compound resin composition, and more specifically, liquid crystal contamination generated by using a silane coupling agent at the same time excellent in adhesion with a glass substrate after photocuring and thermosetting by including the hybrid monomolecular particles Solving the problem of the present invention relates to a sealing compound resin composition particularly useful for liquid crystal display devices.

In recent years, liquid crystal display devices having light weight and high definition have been widely used as display panels of large screens as well as small mobile phones. In the method of manufacturing such a liquid crystal display panel, a conventional liquid crystal display cell is a method of sealing a liquid crystal injection hole formed by sealing two ITO glass substrates with a sealant other than the liquid crystal injection hole by forming a seal pattern with a sealing agent and then thermosetting the sealing pattern. The liquid crystal was injected, and the liquid crystal injection hole was sealed with an end-sealing material to manufacture a liquid crystal display device.

However, the manufacturing method using the inlet sealant has a long process time for injecting the liquid crystal and heats it at a high temperature of about 150 ° C. during thermosetting, so that the adhesiveness of the organic substrate is reduced due to thermal deformation, misalignment and gap unevenness. The problem of color unevenness by the inlet sealant has arisen.

In addition, the photocuring method of curing a liquid crystal display cell only by photocuring has a problem of large curing shrinkage and a weak adhesive strength, and in particular, a problem of uncuring in the light shielding portion due to the black matrix due to the panel structure has not been put to practical use.

In recent years, as a liquid crystal dropping method using the sealing compound which used photocuring thermosetting together for the enlargement of a liquid crystal display element, and shortening of a manufacturing process time, a sealing compound pattern is formed in one transparent substrate, a liquid crystal is dripped inside, BACKGROUND OF THE INVENTION A manufacturing method of a liquid crystal display cell that overlaps and seals another transparent substrate is known.

However, in the case of the sealing compound which used photocuring thermosetting together, the problem that the adhesive force with a glass substrate falls remarkably compared with the sealing compound which uses only the epoxy resin thermosetting alone has emerged. On the other hand, there is a method such as addition of a silane coupling agent, but the effect of improving adhesion is insufficient, and the silane coupling agent component contained in the sealing agent is caused by contact between the liquid crystal and the uncured sealing agent in the liquid crystal dropping method. The problem of eluting with this liquid crystal and contaminating the liquid crystal occurred. In addition, since most of the silane compounds are highly volatile, most of them are used to increase the adhesive strength during the UV curing and thermosetting processes, but they cause outgassing.

On the other hand, there is a method of adding the fine particles of the rubber component to improve the adhesive strength to the epoxy resin adhesive and the technology to improve the adhesive strength by absorbing the stress from the outside by using the core-cell copolymer, but these methods also the particles by heating The adhesive strength due to swelling is improved, but in the case of the photocuring type, or the photo-thermosetting combination which proceeds thermal curing after the photocuring first, there is a limit in improving the adhesive strength. Moreover, the improvement of the adhesive force with the ITO glass substrate by which the sealing compound resin composition for liquid crystal display elements directly contacts with the core cell type copolymer applied to the photo-thermosetting combined sealing agent is also insignificant.

The present invention is to solve the above problems,

A sealing resin composition for liquid crystal display devices, comprising a curable resin, a thermosetting agent, a radical photopolymerization initiator, an inorganic filler, and organic-inorganic hybrid monodisperse polymer particles, thereby reacting with a hydrolyzable functional group and an organic substance that react with inorganic materials such as glass and metal. Adhesion strength and liquid crystal contamination to liquid crystals by newly synthesizing hybrid monodisperse particles of inorganic-organic complex system that combine organic and inorganic materials with organic functional groups that react with materials and use them in sealing resin compositions The aim is to improve. In particular, it is an object of the present invention to provide a sealing compound resin composition capable of exhibiting an adhesive force equal to or higher even without using a silane coupling agent which is the biggest cause of liquid crystal contamination.

The sealing compound resin composition according to the present invention is characterized by comprising a curable resin, a thermosetting agent, a radical photopolymerization initiator, an organic-inorganic hybrid monodisperse polymer particle and an inorganic filler which is a partial epoxy (meth) acrylate resin.

In addition, the hybrid monodisperse polymer particles are copolymers obtained by radical polymerization of an alkoxysilane (meth) acrylate monomer and one or more radical polymerizable monomers, and are characterized by including an alkoxysilane group on the surface thereof.

In addition, one or more kinds of radically polymerizable monomers, one of the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, (meth) acrylic acid It is characterized in that the above selection.

In addition, the hybrid monodisperse polymer particles are characterized in that the particle size is 3㎛ or less.

In addition, with respect to 100 parts by weight of the sealant resin composition, 30 to 80 parts by weight of the curable resin, 1 to 30 parts by weight of the thermosetting agent, 0.1 to 4 parts by weight of the radical photopolymerization initiator, 5 to 5 parts by weight of the inorganic filler 30 parts by weight, the hybrid monodisperse particles are characterized in that it comprises 1 to 30 parts by weight.

Hereinafter, the present invention will be described in more detail.

The sealing compound resin composition of the present invention is characterized by comprising (A) curable resin, (B) thermosetting agent, (C) radical photopolymerization initiator, and (D) organic-inorganic hybrid monodisperse polymer particles. Additionally, (E) may further include an inorganic filler as an essential ingredient. The sealing compound resin composition of the present invention has an inorganic-organic complex system having a hydrolysable functional group that reacts with inorganic materials such as glass and metal and an organic functional group that reacts with an organic material at the same time, thereby bonding organic materials and inorganic materials. Including the hybrid monodisperse particles, the adhesion strength is greatly improved and the liquid crystal contamination is improved, and thus it may be particularly useful as a sealing agent of the liquid crystal display device.

(A) curable resin

As curable resin of this invention, thermosetting and / or photocurable resin can be selected and used without a restriction | limiting. In particular, a curable resin known in the art may be used as the sealant curable resin. Although the usage-amount of curable resin is not restrict | limited, It is 30-80 weight part with respect to 100 weight part of sealing resin compositions, Preferably 50-75 weight part is used. In addition, the curable resin may be one having a viscosity of 50,000 to 200,000cps after synthesis and purification.

As a preferable example of the said curable resin, a partial epoxy (meth) acrylate resin can be used. Partial epoxy (meth) acrylate resin is obtained by reacting an epoxy resin with (meth) acrylic acid. When reacting with an epoxy resin and (meth) acrylic acid, an epoxy group is ring-opened by (meth) acrylic acid and the epoxy group is completely (meth) acrylic. The di (meth) acrylate resin and the epoxy group refer to a mixture of mono (meth) acrylate resin in which only a part of the (meth) acrylates are used, and the concept includes that an unreacted epoxy resin remains. In the present invention, (meth) acryl means acryl or methacryl. There may be many changes in the inherent physical properties depending on the ratio of the epoxy group (meth) acrylic acid.

Examples of the epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AD type epoxy resins, novolac type epoxy resins, naphthalene type epoxy resins, trisphenol methane type epoxy resins, and glycidyl amine type epoxy resins. Can be used

The said partial epoxy (meth) acrylate is obtained by making 0.5-1.8 equivalents of acrylic acid react with 2 equivalents of epoxy, and amines, an inorganic alkali compound, etc. are used as a reaction catalyst. Specific examples of the amines include triethylamine, dimethylamine, trimethylamine, triethylamine, benzylmethylamine, and the like, and specific examples of the inorganic alkali compounds include sodium chromate and sodium hydrogencarbonate.

(B) Thermosetting agent

As the thermosetting agent of the present invention, it is preferable to use a latent thermosetting agent which does not occur at low temperature but hardens at a high temperature. As a latent thermosetting agent, amine type, imidazole type, and dihydrazide type can be used, but it is preferable to use a dihydrazide type hardening | curing agent from a liquid-crystal contamination property and storage stability point.

Specific examples of the amine type are azicure MY-24, azicure MY-H, azicure MY-HK, azicure PN-23J, azicure PN-31J, azicure PN-40J, (manufactured by Ajinomoto), Fujicure FXR -1020, Fujicure FXR-1030 (manufactured by Fuji Kasei Co., Ltd.), and the like, and specific examples of the imidazole type include 2-methylimidazole, 2-undecylimidazole, 2-phenylimidazole, 2- Phenyl-4-methylimidazole (manufactured by Shikoku Chemical Co., Ltd.) and the like, and specific examples of the dihydrazide type include azicure VDH, azicure UDH (manufactured by Ajinomoto Co., Ltd.) ADH, SDH, DDH, and IDH (manufactured by Otsuka Chemical Co., Ltd.). ) And NDH (manufactured by Nippon Hydrazine Co., Ltd.) and the like, and may be used alone or in combination of two or more.

When using a latent thermosetting agent, in order to maintain a cell gap, it is preferable to use the average particle diameter of 5 micrometers or less, Preferably it uses 3 micrometers or less. When the average particle diameter of latent thermosetting agent exceeds 5 micrometers, cell gap is not maintained at the time of upper and lower ITO glass adhesion, and it becomes a cause of a defect. The usage-amount of a latent thermosetting agent is 1-30 weight part with respect to 100 weight part of sealing compound resin compositions, Preferably it is 5-20 weight part.

(C) Radical Photopolymerization Initiator

Radical photopolymerization initiators of the present invention can be used without limitation photoinitiators used in the art, preferred examples are benzophenone, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl- 1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1- [ 4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2,2-dimethoxy- 1,2-diphenylethanone, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, etc. are mentioned.

The usage-amount of a photoinitiator is 0.1-4 weight part with respect to a sealing resin composition, Preferably it is 1-3 weight part.

(D) organic-inorganic hybrid Monodispersion  Polymer particles

The hybrid monodisperse particles of the present invention are characterized in that the copolymer is obtained by radical polymerization of an alkoxysilane (meth) acrylate monomer with one or more kinds of radical polymerizable monomers. In particular, since the surface contains an alkoxysilane group, the adhesive force is greatly improved due to the reaction with inorganic materials such as glass and metal.

One kind of the alkoxysilane (meth) acrylate monomer may be used, and various kinds may be used. As an example, acrylosilane monomer may be used. In order for an alkoxysilane group to exist on the surface of a hybrid monodisperse polymer particle, it is preferable that carbon number of the ester group of an alkoxysilane (meth) acrylate is 3-6 preferably. In addition, the alkoxy of the alkoxysilane (meth) acrylates are each independently and carbon number is not limited, but 1 to 4 is preferred.

As said one or more kinds of radically polymerizable monomers, (meth) acryl, such as (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and butyl (meth) acrylate At least one selected from the group consisting of a latex, (meth) acrylic acid, and alkyl (meth) acrylic acid may be included, and other radically polymerizable monomers may be further included.

In addition, in the case of the polydisperse hybrid particles, it is preferable to use the monodisperse particles because the rheological properties are poor and the ability to improve adhesion is not superior to the monodisperse hybrid particles. The size of the hybrid monodisperse particles is 0.01 µm or more and 3 µm or less, preferably 0.1 µm or more and 1 µm or less. The usage-amount of a hybrid monodisperse particle | grain is 1-30 weight part with respect to 100 weight part of sealing compound resin compositions, Preferably it is 5-20 weight part.

(E) weapon Filler

As the inorganic filler, commercially available fillers such as silica or talc may be used. Especially, it is preferable to use what particle size is 3 micrometers or less. The usage-amount of an inorganic filler is 5-30 weight part with respect to 100 weight part of sealing compound resin compositions, Preferably it is 10-25 weight part.

In addition to the above components, the sealing compound resin composition of the present invention may further include an additive added in the technical field of the present invention. That is, in order to lower the stress as necessary, silicone rubber, silicone oil, acrylic core cell resin, polybutadiene resin, and the like may be further added and blended, and this is not excluded from the present invention. Moreover, antioxidant, antifoamer, surfactant, stabilizer, etc. can also be added further.

The present invention will be described in more detail by the following examples and experimental examples, the following examples are only some specific examples of the present invention and are not intended to limit or limit the scope of the present invention.

< Synthesis Example  1>

Bisphenol A partial epoxy Acrylate  synthesis

The temperature was raised to 80 degreeC, stirring and adding 700 g of liquid bisphenol-A diglycidyl epoxy resins (Epiclon 850S, the Dainippon Inky Chemical Co., Ltd. make) and the catalyst, 1 g of triethylamines, and 2 g of 4-methoxyphenols. .

200 g of methacrylic acid was added dropwise, and the mixture was stirred under reflux for 5 hours. Toluene and 1% oxalic acid were added to the obtained partial epoxy methacrylate resin, followed by stirring to remove ions, and then toluene and 1% oxalic acid were removed to obtain bisphenol A type epoxy methacrylate. As a result of measuring the synthesized bisphenol-type partial epoxy methacrylate by GPC (manufactured by Agilent, THF), the epoxy group was ring-opened by methacrylic acid, and 35% of the dimethacrylate resin in which the epoxy group was completely acrylated, and only part of the epoxy group was acrylated. 45% of the monomethacrylate resin and 20% of the unreacted epoxy resin were contained.

< Synthesis Example  2>

Monodispersion hybrid  Particle Synthesis (1 μm)

0.5 parts by weight of potassium persulfate (manufactured by Aldrich) was added to 50 parts by weight of distilled water to completely dissolve the potassium persulfate. 500 parts by weight of methanol and 250 parts by weight of water are added to the reactor and stirred at 150 RPM. 30 parts by weight of methyl methacrylate (manufactured by Aldrich), 10 parts by weight of butyl acrylate (manufactured by Aldrich), 5 parts by weight of methyl methacrylate (manufactured by Aldrich), trimethoxysilylpropylmethacrylate (manufactured by Shin-Etsu Co., Ltd.) 5 Part by weight and raise the temperature to 70 ℃. When the temperature reaches 70 ° C., potassium persulfate solution is added to the reactor.

After 12 hours, 1 μm monodisperse hybrid particles were prepared, and 1 μm monodisperse hybrid particles were separated using a centrifuge. The separated layer was dried and used to disintegrate.

< Synthesis Example  3>

Monodispersion hybrid  Particle Synthesis (300nm)

20 parts by weight of methanol and 1 part by weight of PVA were added to a 500 mL flask, and the temperature was raised to 70 ° C. at room temperature, followed by stirring for 30 minutes. 100 parts by weight of distilled water, 0.1 parts by weight of AIBN, 30 parts by weight of methyl methacrylate (manufactured by Aldrich), 10 parts by weight of butyl acrylate (manufactured by Aldrich), 5 parts by weight of methylmethacrylic acid (manufactured by Aldrich), trimethoxysilyl 5 parts by weight of propylmethacrylate (manufactured by Shin-Etsu Co., Ltd.) is added thereto, stirred for 5 minutes and then added to the flask. After 12 hours, 300 nm nano-hybrid monodisperse particles were separated by a centrifuge. The separated layer was dried and used to disintegrate.

< Comparative Synthesis Example  1>

Polydispersion hybrid  Particle synthesis

0.5 parts by weight of potassium persulfate (manufactured by Aldrich) was added to 50 parts by weight of distilled water to completely dissolve the potassium persulfate. 500 parts by weight of methanol and 250 parts by weight of water are added to the reactor, followed by stirring at 50 RPM. 30 parts by weight of methyl methacrylate (manufactured by Aldrich), 10 parts by weight of butyl acrylate, 5 parts by weight of methyl methacrylate (manufactured by Aldrich), 5 parts by weight of trimethoxysilylpropyl methacrylate (manufactured by Shin-Etsu Co., Ltd.) Raise the temperature to 60 ° C. When the temperature reaches 60 ° C., potassium persulfate solution is added to the reactor.

After 12 hours, polydisperse hybrid particles were prepared, and the polydisperse hybrid particles were separated using a centrifuge. The separated layer was dried and used to disintegrate.

< Example  1>

69 parts by weight of the partial epoxy methacrylate synthesized in Synthesis Example 1, 11 parts by weight of VDH-J (manufactured by Ajinomoto Co., Ltd.) as a latent thermosetting agent, 2 parts by weight of Igacure 651 (manufactured by Ciba Specialty Co., Ltd.) as a photopolymerization initiator, inorganic 10 parts by weight of SO-E2 (manufactured by Admatech Co., Ltd.) as a filler and 8 parts by weight of the hybrid monodisperse particles synthesized in Synthesis Example 2 were mixed, milled sufficiently with a 3-roll mill, degassed with a rotating revolving defoamer and sealed. The resin composition was obtained.

< Example  2>

All blending ratios were blended in the same manner as in Example 1, and instead of the hybrid monodisperse particles of Synthesis Example 2, 8 parts by weight of the hybrid monodisperse particles synthesized in Synthesis Example 3 were mixed, and then sufficiently milled with a 3-roll mill, and a rotating revolving defoamer It was defoamed with and the sealing resin composition was obtained.

< Comparative example  1>

69 parts by weight of partial epoxy methacrylate synthesized in Synthesis Example 1, 11 parts by weight of VDH-J (manufactured by Ajinomoto Co., Ltd.) as a latent thermosetting agent, 2 parts by weight of Igacure 651 (manufactured by Ciba Specialty Co., Ltd.) as a photopolymerization initiator, inorganic 18 parts by weight of SO-E2 (manufactured by Admatech Co., Ltd.) and 1 part by weight of KBM-403 (manufactured by Shin-Etsu Co., Ltd.) as a filler were sufficiently milled with a 3-roll mill, and defoamed with a rotating revolution defoaming machine to seal the resin composition. Got.

< Comparative example  2>

All blending ratios were blended in the same manner as in Example 1, and instead of the hybrid monodisperse particles of Synthesis Example 2, 8 parts by weight of the hybrid multi-molecular particles synthesized in Comparative Synthesis Example 1 were blended, and then sufficiently milled with a 3-roll mill, followed by rotating revolution. Defoaming in aeration gave a sealing resin composition.

< Comparative example  3>

All the blending ratios were blended in the same manner as in Example 1, and 8 parts by weight of core cell-type monodisperse particles (F-351, manufactured by Nippon Zeon) and 1 part by weight of KBM-403 (manufactured by Shin-Etsu Corp.) instead of the hybrid monodisperse particles of Synthesis Example 2. After mix | blending, it milled sufficiently by the 3-roll mill, defoamed with the rotating revolving deaerator, and obtained the sealing compound resin composition.

< Comparative example  4>

All the blending ratios were blended as in Example 1, and 8 parts by weight of core-cell monodisperse particles (F-351, manufactured by Nippon Zeon) were added instead of the hybrid monodisperse particles of Synthesis Example 2, and then milled sufficiently with a 3-roll mill. It degassed with the rotating revolving degassing machine, and obtained the sealing compound resin composition.

< Experimental Example >

1. Measurement of adhesive strength

It is applied to the center of the cleaned ITO glass substrate (manufactured by Samsung Corning Co., Ltd.) before curing, and after mounting an ITO glass substrate of the same size on the substrate, UV curing (3.5 J / cm 2) and thermal curing (120 ° C., 1 hour). After mounting the support apparatus on the obtained glass surface, the test piece for adhesive strength measurement was produced. The prepared specimens were measured for adhesive strength using UTM equipment (manufactured by Instron Co., Ltd.).

2. Impurity elution experiment with liquid crystal ( GC -MS measurement)

0.5 g of the sealing compound before curing was put in an ampoule, and 1 g of TN liquid crystal (manufactured by Merck) was put in the ampoule. UV curing (3.5 J / cm 2) and thermal curing (120 ° C., 1 hour). The liquid crystal and the blank liquid crystal were taken from the sealing resin composition to determine whether impurities were eluted into the liquid crystal, and GC-MS was measured to determine the presence or absence of an impurity peak.

○: impurity peaks

X: no impurity peak

TABLE 1

Composition Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Curable resin Synthesis Example 1 69 69 69 69 69 69 Thermosetting agent VDH-J 11 11 11 11 11 11 Photoinitiator Irgacure651 2 2 2 2 2 2 Inorganic fillers SO-E2 10 10 18 10 10 10 Hybrid monomolecular particles Synthesis Example 2 8 - - - - - Synthesis Example 3 - 8 - - - - Polydisperse particles Comparative Synthesis Example 1 - - - 8 - - Core cell F-351 - - - - 8 8 Silane coupling agent KBM-403 - - One - One - Adhesive strength (kgf / ㎠) 35 40 21 19 25 18 Impurity Elution to Liquid Crystals (GC-MS) X X ○ ○ ○ X

In the sealing resin composition according to the present invention, in order to simultaneously improve the adhesive strength and liquid crystal contamination property, it was found that the adhesive strength is greatly increased by newly synthesizing hybrid monodisperse particles of organic and inorganic composites and adding them to the sealing resin composition. It is particularly effective as a sealing resin composition for liquid crystal display devices without the use of a silane coupling agent which is the biggest cause of liquid crystal contamination.

Claims (5)

The sealing compound resin composition which consists of curable resin which is a partial epoxy (meth) acrylate resin, a thermosetting agent, a radical photoinitiator, organic-inorganic hybrid monodisperse polymer particle, and an inorganic filler. The method of claim 1, wherein the hybrid monodisperse polymer particles are copolymers obtained by radical polymerization of an alkoxysilane (meth) acrylate monomer with one or more radical polymerizable monomers, and include an alkoxysilane group on the surface thereof. Sealant resin composition. The said one or more radically polymerizable monomer is a methyl (meth) acrylate, ethyl (meth) acrylate, a propyl (meth) acrylate, a butyl (meth) acrylate, and (meth) acrylic acid of Claim 2 The sealing compound resin composition, characterized in that at least one selected from the group consisting of. The sealing compound resin composition according to claim 1, wherein the hybrid monodisperse polymer particles have a particle size of 3 µm or less. The said curable resin is 30-80 weight part, the said thermosetting agent is 1-30 weight part, The said radical photoinitiator is 0.1-4 weight part with respect to 100 weight part of said sealing resin compositions, The said inorganic The filler is 5 to 30 parts by weight, the sealant resin composition, characterized in that the hybrid monodisperse particles contain 1 to 30 parts by weight.