KR101785731B1 - Adhesive composition, display device comprising the adhesive composition and manufacturing method of the same - Google Patents

Abstract

The adhesive composition according to one embodiment of the present invention comprises 5 to 50 parts by weight of an acrylic monomer, 10 to 40 parts by weight of an acrylic copolymer resin, 10 to 20 parts by weight of a crosslinkable monomer, 1 to 20 parts by weight of an adhesion promoter and 1 to 3 parts by weight of a photoinitiator Section.

Description

TECHNICAL FIELD [0001] The present invention relates to an adhesive composition, a display device including the adhesive composition, and a method of manufacturing the same. [0002]

The present invention relates to an adhesive composition, a display device including the same, and a method of manufacturing the same, and more particularly, to an adhesive composition capable of improving transmittance, productivity, and impact resistance, a display device including the same, and a method of manufacturing the same.

2. Description of the Related Art In recent years, various display devices capable of reducing weight and volume, which are disadvantages of CRT (Cathode Ray Tube), have been developed. Examples of the display device include a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an organic light emitting display (OLED) Organic Light Emitting Display Device).

The display device has a transparent glass substrate on the front surface of the display panel and may be damaged by an external impact or the like. To prevent such a problem, a cover substrate capable of protecting the display panel is adhered to the front surface of the display panel.

However, when the display panel and the cover substrate are adhered to each other, particularly when an adhesive is applied to the outer frame portion of the display panel and adhered to the cover substrate, an air layer is present between the display panel and the cover substrate. Accordingly, the light emitted from the display panel and the light incident from the outside are reflected or scattered at the interface between the cover substrate and the air layer, or at the interface between the display panel and the air layer, and the visibility is deteriorated.

The present invention provides an adhesive composition capable of improving transmittance, productivity, and impact resistance, a display device including the same, and a method of manufacturing the same.

In order to achieve the above object, an adhesive composition according to an embodiment of the present invention comprises 5 to 50 parts by weight of an acrylic monomer, 10 to 40 parts by weight of an acrylic copolymer resin, 10 to 20 parts by weight of a crosslinkable monomer, And 1 to 3 parts by weight of a photoinitiator.

The acrylic copolymer resin may be urethane acrylate or urethane methacrylate.

The acrylic monomer may be selected from the group consisting of 2-butoxyethyl acrylate, 2-butoxyethyl methacrylate, 2-ethoxyethyl acrylate, 2-ethoxyethyl methacrylate, Adamantyl methacrylate, 2-methyl-2-adamantyl methacrylate, 2-methyl-2-adamantyl methacrylate, benzyl acrylate, (Ethyleneglycol) ethyl ether methacrylate, di (ethylene glycol) methyl ether methacrylate, dicyclopentanyl acrylate, epoxy acrylate, ethylene glycol methyl acrylate, Ether acrylate, ethylene glycol phenyl ether acrylate, hydroxypropyl acrylate, isobornyl acrylate, methyladamantyl acrylate, neopentyl glycol benzonate acrylate Acrylate, dicyclopentyl methacrylate, epoxycyclohexylmethyl methacrylate, ethylene glycol monomethyl acrylate, ethylene glycol monoacrylate, ethylene glycol monoacrylate, ethylene glycol monoacrylate, But are not limited to, glycidyl methacrylate, glycol phenyl ether methacrylate, hydroxybutyl methacrylate, hydroxypropyl methacrylate, isobornyl methacrylate, glycidyl methacrylate, methyladamethylene methacrylate, methyl methacrylate, Methacrylate; Acrylate, isobutyl acrylate, tert-butyl acrylate, lauryl acrylate, alkyl acrylate, 2-hydroxy acrylate, trimethoxy butyl acrylate, ethyl carbitol acrylate, phenoxy ethyl acrylate, Butyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate and methacrylates thereof; 3-fluoroethyl acrylate, 4-fluoropropyl acrylate and methacrylates thereof; Triethylsiloxane ethyl acrylate, and methacrylates thereof. ≪ Desc / Clms Page number 7 >

The crosslinkable monomer may be selected from the group consisting of 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,3-butylene glycol diacrylate, neopentyl glycol diacrylate, ethylene glycol diacrylate, diethylene Glycol diacrylate, propylene glycol dimethacrylate, pentaerythritol tetraacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, pentaerythritol triacrylate, Ethylene glycol diacrylate, dipentaerythritol diacrylate, sorbitol triacrylate, bisphenol A diacrylate derivatives, trimethylpropane triacrylate, and methacrylates of these. May be any one or more selected from the group consisting of

The adhesive composition may have a viscosity of 50 cp or less.

Further, a display device according to an embodiment of the present invention includes a display panel and a cover substrate adhered to the display panel through an adhesive, and the adhesive may be formed of the adhesive composition described above.

The adhesive may have a modulus of 1 to 5 Gps.

The adhesive may have a transmittance of 90% or more.

The adhesive may have a refractive index of 1.45 to 1.55.

According to another aspect of the present invention, there is provided a method of manufacturing a display device, including: forming an adhesive composition on a display panel by slit coating; vacuum-bonding the display panel and the cover substrate; And curing.

The UV irradiation energy may be 500 mJ / cm 2 or less.

The adhesive composition according to an embodiment of the present invention has a low viscosity and can be coated by a slit coating method and has a low curing energy, thereby enabling quick curing and simplifying a manufacturing process time. In addition, since the transmittance is high and the refractive index is 1.45 to 1.55, there is an advantage that loss of light of the display panel can be prevented. Further, by having a modulus of 1 to 5, there is an advantage that the impact resistance due to an external impact can be secured.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a display device according to an embodiment of the present invention. Fig.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view illustrating a display device according to an embodiment of the present invention.

Referring to Fig. 1, the display device of the present invention includes a display panel 30, and a cover substrate 60 adhered to the display panel 30 through an adhesive 50. Fig.

In more detail, the display panel 30 is formed by bonding substrates made of glass or plastic, and a display element (not shown) interposed therebetween to realize an image. The display panel 30 may include a liquid crystal panel, a plasma display panel, a field emission display panel, or an organic light emitting diode display panel. And is not particularly limited. In the following description, the display panel 30 is a liquid crystal panel.

A backlight unit 10 is disposed under the display panel 30 to provide light to the display panel 30. The cover substrate 60 is adhered to the display panel 30 through the adhesive 50 and the display panel 30 and the cover substrate 60 constructed as described above are housed in the housing 40 to constitute a display device. Here, the cover substrate 60 is made of tempered glass, reinforced plastic, or the like, and physically protects the display panel 30 from external impacts. In order to attach the display panel 30 and the cover substrate 60, an adhesive 50 is interposed therebetween. The adhesive 50 fills a gap between the display panel 30 and the cover substrate 60 to prevent the air layer from being present between the display panel 30 and the cover substrate 60. Hereinafter, the adhesive 50 used in the display device of the present invention will be described in detail.

The adhesive according to one embodiment of the present invention is an UV curable adhesive which is cured by UV (ultraviolet) curing, and includes an acrylic copolymer resin, an acrylic monomer, a crosslinkable monomer, a photoinitiator and an additive.

More specifically, the acrylic copolymer resin regulates the elasticity and the refractive index of the adhesive, and is made of urethane acrylate or urethane methacrylate. The acrylic copolymer resin is contained in an amount of 10 to 40 parts by weight based on 100 parts by weight of the whole adhesive composition.

Wherein the acrylic monomer provides an adhesive force, wherein the acrylic monomer is selected from the group consisting of 2-butoxyethyl acrylate, 2-butoxyethyl methacrylate, 2-ethoxyethyl acrylate, 2-ethoxyethyl methacrylate, 2-adamantyl methacrylate, 2-hydroxyethyl acrylate, 2-methyl-2-adamantyl acrylate, 2-methyl-2 Di (ethylene glycol) ethyl ether methacrylate, di (ethylene glycol) methyl ether methacrylate, dicyclopentyl methacrylate, dicyclopentyl methacrylate, Epoxycyclohexyl acrylate, cyclopentanyl acrylate, epoxy acrylate, ethylene glycol methyl ether acrylate, ethylene glycol phenyl ether acrylate, hydroxypropyl acrylate, isobornyl acrylate, Acrylate, neopentyl glycol benzoate acrylate, 2-hydroxyethyl methacrylate, adamantyl methacrylate, allyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, dicyclopentyl methacrylate Acrylate, methacrylic acid, methacrylic acid, methacrylic acid, methacrylic acid, methacrylic acid, methacrylic acid, maleic anhydride, Methyl methacrylate, methyl glycidyl methacrylate; Acrylate, isobutyl acrylate, tert-butyl acrylate, lauryl acrylate, alkyl acrylate, 2-hydroxy acrylate, trimethoxy butyl acrylate, ethyl carbitol acrylate, phenoxy ethyl acrylate, Butyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate and methacrylates thereof; 3-fluoroethyl acrylate, 4-fluoropropyl acrylate and methacrylates thereof; Triethylsiloxy ethyl acrylate, and methacrylates thereof, or a mixture of two or more thereof. The acrylic monomer is contained in an amount of 5 to 50 parts by weight based on 100 parts by weight of the total adhesive composition.

The crosslinkable monomer controls the degree of curing of the adhesive. For example, the crosslinkable monomer may be 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,3-butylene glycol diacrylate , Neopentyl glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, propylene glycol dimethacrylate, pentaerythritol tetraacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, di Pentaerythritol tetraacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, pentaerythritol hexaacrylate triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol diacrylate, sorbitol triacrylate, bisphenol A diacryl Lt; RTI ID = 0.0 > methacrylate < / RTI > And the like, and they may be used singly or in combination of two or more. The crosslinkable monomer is contained in an amount of 10 to 20 parts by weight based on 100 parts by weight of the total adhesive composition.

The photoinitiator regulates the degree of curing of the adhesive. The photoinitiator may be a poly [polyoxyethylene 4,4'-azobis- (4-cyanopentanoate), 2,2-azobisisobutyronitrile, 2,2- Bis (2,4-dimethylvaleronitrile), 2,2-azobis (4-methoxy 2,4-dimethylvaleronitrile), 1,1-azobis (cyclohexane-1-carbonitrile) 2,2-azobisisobutylate; Benzoyl peroxide, lauroyl peroxide, t-butyl peroxypivalate, 1,1-bis- (t-butylpoxy) cyclohexane or a redox initiator containing hydrogen peroxide or peroxide. Further, it is also possible to use 4,4'-diethoxyacetophenone such as 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylpropriophenone, pt-butyltrichloroacetophenone, pt- 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1-one, 2-benzyl- Acetophenone-based compounds such as 2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one; Benzophenone, p- (diethylamino) benzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, benzoylbenzoic acid, Benzophenone compounds such as methyl benzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4,4'-bis (dimethylamino) benzophenone and 4,4'-bis (diethylamino) ; Thioxanthone, 2-crothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2- Thioxanthone compounds such as thanthone; Benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether and benzyl dimethyl ketal; 2,4,6-trichloro-s-triazine, 2-phenyl 4,6-bis (trichloromethyl) -s-triazine, 2- (3 ', 4'-dimethoxystyryl) (Trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) 4,6-bis (trichloromethyl) -s-triazine, 2,4-bistricloromethyl-6-p-methoxystyryl-s-triazine, 2-p-methoxystyryl- (Trichloromethyl) -s-triazine, 2-phenyl 4,6-bis (trichloromethyl) -bis trichloromethyl-s-triazine, 2- (trichloromethyl) -6-styryl s-triazine, 2- (naphtho l-yl) -4,6-bis (trichloromethyl) -s- triazine, 2- (4-methoxynaphtho-1-yl) -4,6-bis (trichloromethyl) -s-triazine, 2-4- trichloromethyl (piperonyl) Triazine-based compounds such as trichloromethyl (4'-methoxystyryl) -6-triazine, 2-dodecylthioxanthone, 2,4- Methylthioxanthone, 2-4-diethylthioxanthone, 2,2-bis-2-chlorophenyl-4,5,4,5-tetraphenyl-2-1,20-biimidazole, Ciba Special Chemical Compounds such as Irgacure 369, Irgacure 651, Irgacure 907, Irgacure 819, Darocur TPO, OXE-01, OXE-02, Adeka N-1919 and NCI-831 may be used alone or in combination. The photoinitiator is included in an amount of 1 to 3 parts by weight based on 100 parts by weight of the total adhesive composition.

The adhesion promoter is a silane coupling agent for improving the adhesive strength of the adhesive, and is preferably at least one selected from the group consisting of 2- (3,4-epoxycyclohexyl) -ethyltrimethoxysilane, 3-glycidoxytrimethoxysilane, 3- Aminopropyltrimethoxysilane, N-2 (aminoethyl) 3-aminopropyltriethoxysilane, N-2 (aminoethyl) Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, N-phenyl- 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, Can be mixed and used. The adhesion promoter is contained in an amount of 1 to 20 parts by weight based on 100 parts by weight of the whole adhesive composition.

As described above, the adhesive according to one embodiment of the present invention comprises 5 to 50 parts by weight of an acrylic monomer, 10 to 40 parts by weight of an acrylic copolymer resin, 10 to 20 parts by weight of a crosslinkable monomer, 1 to 20 parts by weight of an adhesion promoter, To 3 parts by weight.

Hereinafter, a method of manufacturing a display device including the above-described adhesive will be described.

2 is a view illustrating a method of manufacturing a display device according to an exemplary embodiment of the present invention.

2 (a), an adhesive 50 made of the above-described adhesive composition is coated on the display panel 30. The above-mentioned adhesive composition comprises 5 to 50 parts by weight of an acrylic monomer, 10 to 40 parts by weight of an acrylic copolymer resin, 10 to 20 parts by weight of a crosslinkable monomer, 1 to 20 parts by weight of an adhesion promoter and 1 to 3 parts by weight of a photoinitiator, the slit coating method can be applied because the viscosity is made 50 cp or less so that slit coating can be performed. Therefore, the adhesive agent 50 is coated on the display panel 30 by a slit coating method. At this time, the adhesive composition (50) is applied to the entire surface of the display panel (30).

Next, referring to FIG. 2B, the display panel 30 to which the adhesive 50 is applied is placed on the stage 130 in the vacuum chamber 120, and the cover substrate 60 is aligned and attached. At this time, the display panel 30 and the cover substrate 60 are vacuum-bonded to each other in the vacuum chamber 120 to prevent bubbles and foreign matter from being generated in the adhesive 50. Ultraviolet rays are irradiated to the adhesive agent 50 between the display panel 30 and the cover substrate 60 for a predetermined period of time to completely cure the adhesive agent 50. Thereafter, 60 are housed in a housing to manufacture a display device.

Hereinafter, a preferred embodiment will be described to facilitate understanding of the present invention. However, the following examples are illustrative of the present invention, but the present invention is not limited to the following examples.

Example 1

30 parts by weight of urethane acrylate as an acrylic copolymer resin, 40 parts by weight of glycidyl methacrylate as an acrylic monomer, 15 parts by weight of pentaerythritol triacrylate as a crosslinkable monomer, and 1 part by weight of a photoinitiator -Hydroxycyclohexylphenylketone was used as 2 parts by weight, and 10 parts by weight of 3-glycidoxypropyltriethoxysilane as an adhesion promoter was mixed and uniformly mixed at room temperature for 24 hours or more to prepare an adhesive composition.

Glycidyl methacrylate

Pentaerythritol triacrylate

Example 2

20 parts by weight of urethane acrylate as an acrylic copolymer resin, 50 parts by weight of glycidyl methacrylate as an acrylic monomer, 17 parts by weight of pentaerythritol triacrylate as a crosslinkable monomer, and 1 part by weight of a photoinitiator -Hydroxycyclohexylphenylketone was used as 2 parts by weight, 3-glycidoxypropyltriethoxysilane was mixed as an adhesion promoter in 13 parts by weight, and the mixture was homogeneously mixed at room temperature for 24 hours or more to prepare an adhesive composition. An adhesive composition was prepared by using 40 parts by weight of epoxy acrylate as an acrylic copolymer resin under the same process conditions as those of the examples.

The viscosity, refractive index, transmittance, modulus and curing energy of the adhesive compositions prepared according to Examples 1 and 2 were measured and are shown in Table 1 below.

Example 1 Example 2 Viscosity (cp) 34 16 Refractive index 1.5 1.45 Transmittance (%) 90.2 95 Modulus (㎬) 3.5 5 Curing energy (mJ / cm 2) 300 300

As shown in Table 1 above, the adhesive composition according to the embodiments of the present invention has a viscosity of 50 cp or less, a refractive index of 1.45 to 1.55, a transmittance of 90% or more, a modulus of 1 to 5 kPa and a curing energy of 500 mJ / .

Therefore, the adhesive composition according to an embodiment of the present invention has a low viscosity and can be applied by a slit coating method, and has a low curing energy, thereby enabling quick curing and simplifying a manufacturing process time. In addition, since the transmittance is high and the refractive index is 1.45 to 1.55, there is an advantage that loss of light of the display panel can be prevented. Further, by having a modulus of 1 to 5, there is an advantage that the impact resistance due to an external impact can be secured.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. In addition, the scope of the present invention is indicated by the following claims rather than the detailed description. Also, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims (11)

5 to 50 parts by weight of an acrylic monomer, 10 to 40 parts by weight of an acrylic copolymer resin, 10 to 20 parts by weight of a crosslinkable monomer, 1 to 20 parts by weight of an adhesion promoter and 1 to 3 parts by weight of a photoinitiator,
The crosslinkable monomer may be at least one selected from the group consisting of pentaerythritol tetraacrylate, dipentaerythritol triacrylate, pentaerythritol hexaacrylate sorbitol triacrylate, bisphenol A diacrylate derivative, trimethylpropane triacrylate, and methacrylates thereof ≪ RTI ID = 0.0 > and / or < / RTI >
The method according to claim 1,
Wherein the acrylic copolymer resin is urethane acrylate or urethane methacrylate.
The method according to claim 1,
The acrylic monomer may be selected from the group consisting of 2-butoxyethyl acrylate, 2-butoxyethyl methacrylate, 2-ethoxyethyl acrylate, 2-ethoxyethyl methacrylate, Adamantyl methacrylate, 2-methyl-2-adamantyl methacrylate, 2-methyl-2-adamantyl methacrylate, benzyl acrylate, (Ethyleneglycol) ethyl ether methacrylate, di (ethylene glycol) methyl ether methacrylate, dicyclopentanyl acrylate, epoxy acrylate, ethylene glycol methyl acrylate, Ether acrylate, ethylene glycol phenyl ether acrylate, hydroxypropyl acrylate, isobornyl acrylate, methyladamantyl acrylate, neopentyl glycol benzonate acrylate Acrylate, dicyclopentyl methacrylate, epoxycyclohexylmethyl methacrylate, ethylene glycol monomethyl acrylate, ethylene glycol monoacrylate, ethylene glycol monoacrylate, ethylene glycol monoacrylate, But are not limited to, glycidyl methacrylate, glycol phenyl ether methacrylate, hydroxybutyl methacrylate, hydroxypropyl methacrylate, isobornyl methacrylate, glycidyl methacrylate, methyladamethylene methacrylate, methyl methacrylate, Methacrylate; Acrylate, isobutyl acrylate, tert-butyl acrylate, lauryl acrylate, alkyl acrylate, 2-hydroxy acrylate, trimethoxy butyl acrylate, ethyl carbitol acrylate, phenoxy ethyl acrylate, Butyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate and methacrylates thereof; 3-fluoroethyl acrylate, 4-fluoropropyl acrylate and methacrylates thereof; Triethylsiloxane ethyl acrylate, and methacrylates thereof. ≪ RTI ID = 0.0 > 18. < / RTI >
delete The method according to claim 1,
Wherein the adhesive composition has a viscosity of 50 cp or less.
Display panel; And
And a cover substrate adhered to the display panel through an adhesive,
Wherein the adhesive is formed from the adhesive composition of any one of claims 1, 2, 3, and 5.
The method according to claim 6,
Wherein the adhesive has a modulus of 1 to 5 Gps.
The method according to claim 6,
Wherein the adhesive has a transmittance of 90% or more.
The method according to claim 6,
Wherein the adhesive has a refractive index of 1.45 to 1.55.
The display panel comprises 5 to 50 parts by weight of an acrylic monomer, 10 to 40 parts by weight of an acrylic copolymer resin, 10 to 20 parts by weight of a crosslinkable monomer, 1 to 20 parts by weight of an adhesion promoter and 1 to 3 parts by weight of a photoinitiator, The monomer may be selected from the group consisting of pentaerythritol tetraacrylate, dipentaerythritol triacrylate, pentaerythritol hexaacrylate sorbitol triacrylate, bisphenol A diacrylate derivatives, trimethylpropane triacrylate, and methacrylates thereof Forming a slit coating on the adhesive composition;
Vacuum-bonding the display panel and the cover substrate; And
And irradiating the adhesive composition with UV to cure the adhesive composition.
11. The method of claim 10,
Wherein the UV irradiation energy is not more than 500 mJ / cm 2.

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