KR20170080436A - Organic nano particle, adhesive film and display device containing the organic nano partilce - Google Patents

Abstract

The present invention relates to a polyimide nanoparticle having a core-shell structure, an adhesive film in which the nanoparticles are dispersed in a binder, and an optical transparent adhesive layer between a display panel and a fixture such as a display panel and a cover glass, And a display device to which an adhesive film is applied as an adhesive material. By dispersing the polyimide nanoparticles having the core-shell nanostructure in the binder, it is possible to improve the heat resistance property and prevent the adhesive property from lowering under high temperature conditions. In addition, the polyimide nanoparticles have excellent displacement and restoration properties, thereby increasing the elastic modulus of the binder. Thus, the polyimide nanoparticles can be utilized in a display device to which a touch panel is applied, or in a borderless type display device having substantially no non- .

Description

TECHNICAL FIELD [0001] The present invention relates to an organic nanoparticle, an organic nanoparticle, an adhesive film including the organic nanoparticle,

More particularly, the present invention relates to an organic nanoparticle having a core-shell structure having excellent heat resistance, shape retention, and anti-UV characteristics, an adhesive film comprising the nanoparticle, and a display device.

BACKGROUND OF THE INVENTION With the development of display technology, display devices such as a liquid crystal display (LCD) and an organic light emitting diode (OLED) display have been applied to displays for computer monitors, TVs, mobile phones, and smart devices . Such a display device includes a display panel that largely implements an image. In order to prevent the display panel from being damaged by external pressure, a cover window made of tempered glass or plastic material is provided on one surface Or the front surface.

Among the methods for attaching the cover window and the display panel, direct bonding is generally used. The direct bonding method uses an optically clear resin (OCR) or an optically clear adhesive (OCA) to cure the OCR or the like to bond the cover glass and the display panel together.

1 is a cross-sectional view schematically showing a display device to which a cover window is attached to a display panel by applying a direct bonding method according to a related art. 1, the display device 1 includes a display panel 10, a cover glass 30 disposed on the outside of the display panel 10, (20) which is applied and hardened. The adhesive layer 20 is usually an optical transparent adhesive (OCA), and an optical transparent resin (OCR) is used.

The adhesive layer 20 made of an optical transparent resin positioned between the display panel 10 and the cover window 30 improves the optical characteristics of the display device 1 and functions as a buffer in an external impact , The impact resistance must be improved. An optical transparent resin (OCR) such as an acrylate resin, a urethane resin or a rubber resin is mainly used for the optical transparent adhesive layer 20 interposed between the display panel 10 and the cover window 30. The acrylate reactive component applied between the display panel 10 and the cover window 30 is cured and shrunk to form the adhesive layer 20 to reduce the stress applied to the display panel 10. [ In addition, the acrylate resin has a low modulus of elasticity to improve the impact resistance.

In recent years, there is a demand for a display device capable of flexibly bending and stretching while realizing a touch. The cover window 30, which was conventionally used as a main component of the tempered glass, is also made of plastic, which is a flexible material. Compared to glass, the plastic material has a soft characteristic and it bends itself. Particularly, plastic materials are vulnerable to heat, and thermal deformation occurs in a high temperature or high temperature and high humidity environment, resulting in non-flatness on the surface.

As described above, acrylate-based, urethane-based and rubber-based adhesives are often used as optical transparent adhesives (OCR) interposed between the display panel 10 and the cover window 30. The optical transparent adhesive should be free from abnormality based on 1000 hours in a high temperature environment of 105 ° C or higher and a high temperature and high humidity environment of 85 ° C or higher and a relative humidity of 85% or higher, and the requirements are expected to increase gradually.

However, the acrylate adhesives, urethane adhesives and rubber adhesives conventionally used as optical transparent adhesives are yellow mura or melting in a high temperature and high temperature and high humidity environment. Therefore, as shown in Fig. 2A, the network structure 22 formed by the resin constituting these adhesives in a high-temperature and high-temperature / high-humidity environment is destroyed to deteriorate the heat resistance characteristics. Additives that are added to inhibit this generate fume gas at high temperatures, which in turn reduces the durability of the optical transparent adhesive.

On the other hand, an adhesive which is obtained by adding a curable silicone component or a urethane prepolymer to an acrylate resin and applying a thermosetting or moisture hardening method is also applied. However, silicon resin or urethane resin has a high modulus of elasticity, which is not only poor in impact resistance, but also poses a problem of securing mass productivity due to high process energy.

Further, in the case of a display device using a force sensing touch panel, the optical transparent adhesive requires a high moving force and a restoring force. However, as shown in FIG. 2B, the acrylate-based adhesive, which has been used as an optical transparent adhesive in the related art, has a problem in that it can not be applied to an optical transparent adhesive of a display device to which a pressure sensitive type touch panel is applied because of its limited restorative force.

On the other hand, among the flat panel display devices, the liquid crystal panel constituting the liquid crystal display device does not have its own light emitting element, and a backlight unit supporting the liquid crystal panel and including a light source is arranged on the back thereof. BACKGROUND ART [0002] Recently, as the screen of a liquid crystal display device becomes larger, researches for reducing a weight and a volume while having a wide display area have been actively conducted. Accordingly, efforts are being made to reduce the weight and thickness of the liquid crystal display device by using a so-called borderless type backlight unit which reduces some components constituting the backlight unit. At the same time, development of a liquid crystal display device having a so-called narrow bezel in which a bezel region, which is a non-display region other than the display region, is narrowed while expanding the display region is actively under development.

3A is a cross-sectional view schematically showing a liquid crystal display device to which a conventional adhesive layer is applied to realize a low-bezel. 3A, the liquid crystal display device 50 to which the conventional adhesive layer 90 is applied includes a liquid crystal panel 60, a backlight unit 70, a main frame 80, and a bottom frame 82 , And an adhesive layer (90) is interposed between the liquid crystal panel (60) and the main frame (80).

The liquid crystal panel 60 is a part for displaying an image and includes a first substrate 62 and a second substrate 64 which are adhered to each other across a liquid crystal layer (not shown) And a first polarizer 56 and a second polarizer 58 formed on the outer surface of the second substrate 64, respectively.

The backlight unit 70 is a part for supplying light to the liquid crystal panel 60 and is disposed under the liquid crystal panel 60 to support the liquid crystal panel 60. [ The backlight unit 70 includes a light emitting diode (LED) assembly (not shown) arranged along the longitudinal direction of at least one edge of the main frame 80, a reflector (not shown) disposed at the top of the bottom frame 82, A light guide plate 72 disposed on an upper portion of a reflection plate (not shown), and a plurality of optical sheets (not shown) disposed on an upper portion of the light guide plate 72. The main frame 80 is disposed on the upper side of the light guide plate 72 and the liquid crystal panel 60 is supported by the main frame 80.

A soft type adhesive has been conventionally used as an adhesive constituting the adhesive layer 90 interposed between the liquid crystal panel 60 and the main frame 80 constituting the backlight unit 70. [ The adhesive force of the adhesive is proportional to the modulus value of the resin constituting the binder of the adhesive, and the resin used for the soft type adhesive 90 has a relatively low modulus value and thus has a relatively weak adhesive force. Since the soft type adhesive is vulnerable to high temperature and high humidity conditions, if the soft type adhesive is left under a condition of high temperature / high humidity (for example, 60 DEG C or more, relative humidity 90%) for several hours, It is damaged. As a result, light leakage occurs in the liquid crystal panel 60 while peeling occurs from the adhesive surface of the soft type adhesive layer 90 interposed between the liquid crystal panel 60 and the backlight unit 70 (see the right side of FIG. 3B) .

In order to prevent this, it may be considered to attach the liquid crystal panel 60 and the backlight unit 70 using a hard type adhesive having excellent adhesive strength. However, since the hard type adhesive has a high modulus value, the shock absorbing property is insufficient. Therefore, when an external impact is applied, the external impact is applied to the liquid crystal panel 60 as it is. The refractive index anisotropy of the substrates 62 and 64 constituting the liquid crystal panel 60 due to the applied external impact is caused and the twist angle is formed in the liquid crystal structure of the liquid crystal layer (not shown) Lt; / RTI >

In general, the substrates 62 and 64 constituting the liquid crystal panel 60 are made of glass, while the main frame 90 constituting the backlight unit 70 is made of a metal material. Accordingly, when the display device 50 is exposed to a high temperature, the substrates 62 and 64 constituting the liquid crystal panel 60 are not deformed by heat. However, the backlight unit 70 made of metal is at least 2 mm .

As the backlight unit 70 is deformed, the shape of the adhesive layer 90 interposed between the backlight unit 70 and the liquid crystal panel 60 is also changed (see the middle drawing of FIG. 3B). The adhesive layer 90 to which the hard type adhesive is applied is delaminated from the backlight unit 70 because the modulus value is relatively high so that the stress due to the expansion of the backlight unit 70 can not be sustained (See right drawing of FIG. As described above, the adhesive interface between the liquid crystal panel 60 and the backlight unit 70 is separated, and light leakage may occur in the liquid crystal panel 60.

In order to solve this problem, it is necessary to enlarge the application area of the adhesive layer 90 to which the conventional soft type and hard type adhesive are applied. Therefore, the application area of the conventional adhesive has a minimum width W1. As the application area of the adhesive applied in the past increases, the non-display area increases in the display device 50, which limits the implementation of the narrow bezel. Further, since the adhesive agent is wasted, the economical efficiency of the process can not be avoided.

In addition, in the ultraviolet (UV) curing process for forming the adhesive layer 20 (see FIG. 1) interposed between the display panel and the cover window and the adhesive layer 90 (see FIG. 3A) interposed between the display panel and the backlight unit This results in yellowing of the adhesive layer, which is pale yellow or brownish. Yellowing may occur in the adhesive layer due to ultraviolet rays, and the adhesive strength of the adhesive layer may be lowered. In addition, especially when yellowing occurs in the adhesive 20 (see Fig. 1) applied to OCA, the optical characteristics such as the transmittance of the display device are deteriorated, resulting in image quality defects.

It is an object of the present invention to provide an organic nanoparticle capable of improving heat resistance and anti-UV characteristics, and an adhesive film and a display device having improved optical properties such as heat resistance and anti-UV characteristics according to dispersion of such organic nanoparticles .

Another object of the present invention is to provide an organic nanoparticle capable of improving a displacement force and a restoring force, and an adhesive film and a display device having improved restoring force according to dispersion of such organic nanoparticles.

According to an aspect of the present invention, there is provided an organic nanoparticle comprising a porous core and a non-porous shell.

For example, the porous core and the non-porous shell may be composed of polyimide.

The organic nanoparticles according to the present invention can improve the restoring force by improving the elasticity against external impact through the porous pore structure formed in the core.

Further, since the organic nanoparticles are excellent in heat resistance and in-UV characteristics, dispersion and doping in the binder can improve the heat resistance and the UV resistance of the binder. That is, by dispersing the organic nanoparticles of the present invention in a binder, it is possible to obtain an adhesive film having improved heat resistance, in-UV characteristics, restoring force, low modulus and excellent anti-shock property.

Therefore, according to another aspect of the present invention, there is provided an adhesive film in which the organic nanoparticles are dispersed and doped in a binder.

According to another aspect of the present invention, there is provided a display device including the adhesive film in which the organic nanoparticles are dispersed.

For example, the adhesive film may be positioned between the display panel of the display device and the cover glass and / or between the display panel and the structure.

The organic nanoparticles synthesized according to the present invention are composed of a polyimide (PI) core having a porous structure and a polyimide shell having a non-porous structure having no pore structure.

Since the organic nanoparticles composed of polyimide are excellent in heat resistance, when dispersed and coated on a binder, the heat resistance of the adhesive film containing the binder can be improved, and deformation of the adhesive film under high temperature conditions can be prevented .

In addition, the organic nanoparticles of the present invention have a porous structure and thus have excellent elastic properties. Therefore, the modulus of the adhesive film can be lowered by using the binder in which the organic nanoparticles synthesized according to the present invention are dispersed, thereby improving the anti-shock property of the adhesive film.

In addition, the inner-UV characteristics can be improved owing to the reflection and scattering effects of light due to the porous structure of the core constituting the organic nanoparticles. In addition, The occurrence of yellowing can be suppressed, and problems such as poor image quality due to reduction in transmittance due to yellowing can be solved.

Therefore, the adhesive film made of the binder in which the organic nanoparticles of the present invention are dispersed can be used not only for an optical transparent adhesive film interposed between a display panel and a cover glass, but also for an adhesive interposed between a display panel and a structure supporting the display panel And can be applied to a display device having a touch panel.

Particularly, the adhesive film in which the organic nanoparticles of the present invention are dispersed has improved in-UV characteristics, and yellowing does not occur due to curing process or subsequent irradiation of external light. Therefore, even when used as an optical transparent adhesive film, an excellent adhesive force can be maintained, and the light-transmission characteristic due to yellowing does not deteriorate, resulting in poor image quality. Therefore, the present invention can be applied to an outdoor display device in which light is strongly irradiated.

In addition, the organic nanoparticles according to the present invention have good dispersion characteristics and do not cause aggregation even when they are dispersed in a binder. Therefore, it can be uniformly dispersed in the binder, and homogeneous physical properties can be ensured for the entire area of the adhesive film.

In addition, when an adhesive film in which nanoparticles according to the invention are dispersed is applied between the display panel and the structure, the heat resistance is excellent, and the modulus value is lowered, so that the adhesion between the display panel and the structure can be maintained even under high temperature and high humidity conditions. Further, since a sufficient adhesive force can be maintained even if the coating is performed with a narrow area, a display device to which a narrow-bezel type narrow bezel is applied can be realized.

1 is a cross-sectional view schematically showing a display device to which a cover window is attached to a display panel by applying a direct bonding method according to a related art.
FIGS. 2A and 2B are views schematically showing a problem that occurs when an acrylate-based adhesive is applied between a cover window and a display panel according to the related art. FIG. 2A shows a problem caused by a decrease in heat resistance, and FIG. 2B shows a problem caused by a decrease in restitution force.
FIGS. 3A and 3B are schematic views illustrating problems that may occur when a soft type adhesive or a hard type adhesive is applied between a display panel and a structure supporting the display panel according to the related art. FIG. 3A is a cross-sectional view schematically showing a display device, and FIG. 3B is a view schematically showing a problem caused by a difference in thermal expansion coefficient between a display panel and a structure when a conventional adhesive is used.
4 is a view schematically showing organic nanoparticles according to an exemplary embodiment of the present invention.
5 is a cross-sectional view schematically showing a display device in which an adhesive film in which organic nanoparticles are dispersed in a binder is applied between a display panel and a cover window according to an exemplary embodiment of the present invention.
6A and 6B are views schematically illustrating an advantage of an adhesive film in which organic nanoparticles of the present invention are dispersed in a binder. FIG. 6A shows that heat resistance degradation can be solved, and FIG. 6B shows that restoration force reduction can be solved.
7A and 7B are views schematically showing a display device in which a composite adhesive film of the present invention is applied between a display panel and a cover window according to an exemplary embodiment of the present invention. Fig. 7A shows a display device in which a display panel and a cover window are directly bonded, and Fig. 7B shows a display device in which a touch panel is interposed between a display panel and a cover window.
8 is a cross-sectional view schematically showing a liquid crystal panel as a display panel according to an exemplary embodiment of the present invention.
9 is a cross-sectional view schematically showing a liquid crystal display in which an adhesive film in which organic nanoparticles are dispersed in a binder is applied between a liquid crystal panel and a backlight unit as a structure according to another exemplary embodiment of the present invention.
10 is a graph showing the relationship between the thermal expansion coefficient of the display panel and the structure of the display panel and the structure of the adhesive film of the present invention when the adhesive film having improved heat resistance and low modulus is applied between the display panel and the structure according to the exemplary embodiment of the present invention Fig. 3 is a view schematically showing a state in which it does not occur.
11 is a diagram illustrating an organic light emitting diode display device in which an adhesive film is applied between an organic light emitting diode display panel and a back cover, which is a structure supporting the organic light emitting diode display panel, according to another exemplary embodiment of the present invention. 1 is a schematic cross-sectional view.
12 is a cross-sectional view schematically showing an organic light emitting diode display panel according to another exemplary embodiment of the present invention.
13A and 13B are SEM photographs showing a porous polyimide core synthesized according to an exemplary embodiment of the present invention.
14A to 14C are SEM photographs showing organic nanoparticles of a porous polyimide core-polyimide shell synthesized according to an exemplary embodiment of the present invention.
15A is a graph showing AFM-IR analysis results of organic nanoparticles synthesized according to an exemplary embodiment of the present invention.
FIG. 15B is a graph and an analysis result showing Py-GC / MS (pyrolyzer-gas chromatography / mass spectrometry) analysis results of the organic nanoparticles synthesized according to the exemplary embodiment of the present invention to be.
15C is a graph showing the results of ¹⁵ N NMR analysis of organic nanoparticles synthesized according to an exemplary embodiment of the present invention.
15D is a graph showing the results of ¹⁹ F NMR analysis of organic nanoparticles synthesized according to an exemplary embodiment of the present invention.
16 is a graph showing a TGA analysis result of an optical transparent adhesive in which organic nanoparticles synthesized according to an exemplary embodiment of the present invention are dispersed in a binder.
17 is a graph showing the results of measurement of storage modulus for an optical transparent adhesive in which organic nanoparticles synthesized according to an exemplary embodiment of the present invention are dispersed in a binder.
18A is a graph showing displacement amount measurement results for an optical transparent adhesive in which organic nanoparticles synthesized according to an exemplary embodiment of the present invention are dispersed in a binder.
18B is a graph showing a result of measurement of restorative amount for an optical transparent adhesive in which organic nanoparticles synthesized according to an exemplary embodiment of the present invention are dispersed in a binder.
19 is a graph showing a TGA analysis result of an elastic adhesive in which organic nanoparticles synthesized according to an exemplary embodiment of the present invention are dispersed in a binder.
20 is a graph showing the results of measurement of tensile modulus for an elastic adhesive in which organic nanoparticles synthesized according to an exemplary embodiment of the present invention are dispersed in a binder.
FIG. 21 is a graph showing the adhesive force evaluation results for an elastic adhesive in which organic nanoparticles synthesized according to an exemplary embodiment of the present invention are dispersed in a binder. FIG.
22 is a graph showing the result of the in-UV evaluation of the elastic adhesive in which the organic nanoparticles synthesized according to the exemplary embodiment of the present invention are dispersed in the binder.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings where necessary.

[Organic nanoparticles]

4 is a view schematically showing organic nanoparticles according to an exemplary embodiment of the present invention. 4, the organic nanoparticles 320 of the present invention include a porous polyimide (PI) core 322 having pores 324 formed therein, a polyimide (PI) core 322 surrounding the porous polyimide And a PI (Shell) shell 326. Polyimide is a polymer resin based on a rigid aromatic main chain, and in particular, an imide ring present in a unit unit is chemically stable. According to the present invention, when having a polyimide structure in a core and a shell, excellent heat resistance, mechanical strength, chemical resistance, UV resistance, and / or electrical characteristics of the polyimide compound can be utilized.

The polyimide constituting the core 322 of the organic nanoparticles 320 according to the present invention has a porous structure in which a plurality of pores 324 are formed. Can be easily deformed by the external pressure by the polyimide core 322 having the porous structure and can be quickly restored to its original position after the pressure is removed or disappeared. At this time, when the organic nanoparticles composed solely of porous polyimide are dispersed in the binder, the binder component can penetrate into the pores. If the binder component penetrates into the pores, it is difficult to maintain the elasticity due to the porous structure, and therefore, it is difficult to expect the improvement of the deformability and the restoring force.

The organic nanoparticles 320 according to the present invention form a non-porous polyimide shell 326 surrounding the porous polyimide core 322. Accordingly, even when the organic nanoparticles 320 of the present invention are doped and dispersed in the binder, the binder component can not penetrate into the pores 324 by the non-porous shell 326, So that it is possible to obtain excellent stability and restoring force.

A porous polyimide (PI) core 322 and a non-porous polyimide shell 326 surrounding the porous polyimide (PI) core are obtained by the condensation reaction of dianhydride and dianhydride, respectively. In one exemplary embodiment, when the organic nanoparticles according to the present invention are used in a non-display area of a display device, for example, when dispersed in an adhesive film interposed between a display panel and a structure supporting the display panel, The porous polyimide core and the non-porous polyimide shell may be transparent materials as well as opaque materials.

In another exemplary embodiment, when the organic nanoparticles according to the present invention are used in a display area of a display device, for example, when dispersed in an optical transparent adhesive film sandwiched between a display panel and a cover window for protecting the display panel , The core constituting the organic nanoparticles and the polyimide constituting the shell may be composed of transparent polyimide (CPI).

As described above, the polyimide is usually prepared by a condensation reaction of a dianhydride and a diamine. At this time, the polyimide is bonded to the dianhydride aromatic ring which is the electron acceptor constituting the main chain and intermolecular bonding of the pi (π) electrons present in the diamine aromatic ring which is the electron acceptor, A charge transfer complex (CTC) occurs. At this time, electrons may be excited because a non-covalent electron pair exists in the imide structure.

From the viewpoint of π-electron transition, polyimide has a large number of aromatic rings, so that the number of resonance structures increases and π-electrons can be easily transferred. Therefore, the energy level is lowered, and accordingly, light of a high wavelength, for example, a visible light wavelength band (general polyimide absorbs light in a wavelength band of 400 to 500 nm) is absorbed and becomes yellowish red.

It is necessary to lower the CTC of the polyimide molecule in order to produce an optically transparent polyimide by removing intrinsic color of the polyimide. For this purpose, a structure capable of decreasing the density of? Electrons, for example, a structure in which an olefinic cyclo-olefin structure other than a benzene ring is introduced to reduce the density of? Electrons, Substituents having strong electronegativity such as fluorine (F), sulfone group (-SO ₂ ) group and ether group (-O-) such as -CF ₃ are introduced to restrict the movement of π electrons, There is a way to lower it.

This method can be used to obtain transparent polyimide particles. Transparency Employing a porous core and shell composed of polyimide may not lower the light transmittance. Therefore, for example, the core 322 made of transparent polyimide and the organic nanoparticles 320 having the structure of the shell 326 are dispersed in the optical transparent resin (OCR) used for adhering and bonding the members in the display device, A transparent adhesive (OCA) can be formed.

In one exemplary embodiment, the dianions that can be used to synthesize the porous polyimide core 322 and the non-porous polyimide shell 326 include pyromellitic dianhydride (PMDA), biphenyl- Biphenyl-3,3 ', 4,4'-tetracarboxylic acid dianhydride (BPDA), 4,4'-oxydiphthalic anhydride (ODPA), benzophenone- 3 ', 4,4'-tetracarboxylic acid dianhydride (BTDA), diphenylsulfone-3,3', 4,4'-tetracarboxylic acid dianhydride (4,4 '- (Hexafluoroisopropylidene) diphthalic anhydride (6FDA), 4,4'- (hexafluoroisopropylidene) diphthalic anhydride, , 1,2,4,5-cyclobutane tetracarboxylic dianhydride (CBDA), 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride (2,4,4-cyclohexane tetracarboxylic dianhydride, CHDA), 4,4'-bisphenol A dianhydride (BPADA), 4- (2,5-dioxotetrahydrofuran 3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride (4- (2,5-Dioxotetrahydrofuran- 1,2-dicarboxylic anhydride (DTDA), bicyclic [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (bicycle [2.2.2] oct- 3,5,6-tetracarboxylic dianhydride; BCDA), 5- (2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride cyclohexene-1,2-dicarboxylic anhydride (DOMDA), ethylene diamine tetraacetic dianhydride (EDTE), benzoquinonetetracarboxylic dianhydride, and naphthalenetetracarboxylic dianhydride. Can be selected from the group.

On the other hand, diamines that can be used for synthesizing the porous polyimide core 322 and the non-porous polyimide shell 326 include p-phenylene diamine (PPD), m-phenylenediamine (m- Phenylene diamine (MPD), 3,4'-oxydianiline (3,4-ODA), 4,4'-oxydianiline ), Biphenyl diamine, 2,2'-bis (trifluoromethyl) -4,4'-biphenyldiamine, TFMB Or TFB), 2,2-Bis [4- (4-aminophenoxy) phenyl] propane, 4,4'-methylenediamine (4,4'-methylene diamine (MDA), cyclohexyl diamine (CHDAM), diaminobenzene cyanide (DABN), 3,4'-oxydiamine , 4'-DPE), 4,4'-diamino bozophenone, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane 2-Bis (3-amino-4-hydroxyphen bis (4-aminophenoxy) phenyl] hexafluoropropane (BAHFP), 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane,

(3-aminophenoxy) benzene, m-BAPB), 4,4'-bis (4-aminophenoxy) biphenyl 4-aminophenoxy biphenyl (p-BAPB), 2,2-bis (3-aminophenyl) hexafluoropropane (BAPF), bis [4- 4- (3-aminophenoxy) phenyl] sulfone, m-BAPS), bis [4- (4-aminophenoxy) phenyl] sulfone, aminophenoxy) phenyl] sulfone, BAPS) , 1,4-bis (4-aminophenoxy) benzene, TPE-Q, 2,2- Aminophenyl) sulfone (p-BAPS), bis (3-aminophenyl) sulfone (APS) , m-xylylenediamine (m-XDA), p-xylylenediamine (p-XDA), 2,2-bis (3-amino-4-methylphenyl) hexafluoropropane 2-bis (3-amino-4-methylphenyl) hexafluoropropane (BAMF), 4,4'-diaminooctafluorobiphenyl enyl), 3,3'-dihydroxybenzidine, 2,2'-ethylenedianilin, 2,2 ', 5,5'-tetrachloro Benzene, 2,2 ', 5,5'-tetrachlorobenzidine, bis (3-aminophenyl) methanone, 2,7-diaminofluorene, 2-chloro-p-phenylenediamine, 1,3-bis (3-aminopropyl) -tetramethyldisiloxane, 1,3- Bis (4-aminophenyl) cyclohexane, 9,9-bis (4-aminophenyl) fluorene, ) fluorine, 5- (trifluoromethyl) -1,3-phenylenediamine, 4,4'-methylenebis (2-methylcyclohexylamine) ( 4-methylenebis (2-methylcyclohexylamine), 4-fluoro-1,2-phenylenediamine, 1,3-bis (aminomethyl) cyclohexane , 3-bis (aminomethyl) cyclohexane; m-CHDA), 1,4-bis (aminomethyl) cyclohexane, p-CHDA, 2,2-bis [4- (4-aminophenoxy) Bis (trifluoromethyl) benzidine, MDB (2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 6FBAPP), 2,2'- ), 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, bis (4-aminophenyl) sulfide, 4 , 4'-SDA).

In one exemplary embodiment, the polyimide that is a constituent of the organic nanoparticles 320 according to the present invention can be represented by the following formula (1), but other dianhydrides and diamines can be used as starting materials.

Formula 1

(Wherein X in the formula (1) is selected from the group consisting of the following X1 to X8, and Y in the formula (1) is selected from the group consisting of the following Y1 to Y5)

;

;

Wherein X1 is pyromellitic dianhydride (PMDA), X2 is biphenyl-3,3 ', 4,4'-tetracarboxylic acid dianhydride (XDA), wherein X1 is derived from dianhydride monomer ; BPDA), X3 is 4,4'-oxydiphthalic anhydride (ODPA), X4 is benzophenone-3,3 ', 4,4'-tetracarboxylic dianhydride , 3 ', 4,4'-tetracarboxylic acid dianhydride (BTDA), X5 is diphenylsulfon-3,3', 4,4'-tetracarboxylic dianhydride acid dianhydride (DSDA), X6 is 4,4 '- (hexafluoroisopropylidene) diphthalic anhydride (4F'), X7 is 1,2,4,5-cyclo Butane tetracarboxylic dianhydride (CBDA), X8 is 1,2,4,5-cyclohexane tetracarboxylic dianhydride, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, CHDA).

Y1 is p-phenylene diamine (PPD), Y2 is 4,4'-oxydianiline (ODA), and Y2 is derived from a diamine monomer. Y3 represents biphenyl diamine, Y4 represents 2,2'-bis (trifluoromethyl) -4,4'-bis (trifluoromethyl) -4, 4'-biphenyldiamine, TFMB or TFB) Y5 was synthesized from 2,2-Bis [4- (4-aminophenoxy) phenyl] propane It is derived.

Next, a method for synthesizing the organic nanoparticles 320 composed of the porous polyimide core 322 and the polyimide shell 326 surrounding the core according to the present invention will be described. The polyimide of the core 322 and the shell 326 constituting the organic nanoparticles are synthesized by condensing a dianhydride monomer and a diamine anhydride to form a precursor polyamic acid (PAA) , The polyimide can be obtained by carrying out an imidization reaction in which the polyamic acid is treated with an appropriate catalyst or a high temperature.

In order to synthesize polyamic acid (PAA) which is a precursor of polyimide, for example, an aromatic dianhydride is reacted with a diamine. When dianhydride is added to the reaction solution in which diamine is dissolved, The polyamic acid condensed with dianhydride can be obtained by ring opening and a midbrain reaction with a diamine. The reaction solvent which may be used hereafter may be N, N-dimethylacetamide, DMAc, N, N-dimethylformamide, N-dimethylacetamide, N- N-methyl pyrolidinone (NMP), m-cresol and the like can be used.

Since the polyamic acid is formed by the nucleophilic substitution reaction between the carbon atom of the carbonyl group of the dianhydride (C = O) and the diamine (nucleophilic substitution reaction), the rate of the reaction is primarily due to the electrophilicity of the carbonyl group, It can be determined by nucleophilicity. At this time, the dianhydride used as the monomer and the diamine can be reacted in a molar ratio of 1: 2 to 2: 1, for example, 1: 1.

As described above, by introducing an olefinic cyclic structure to dianhydride and / or diamine used as a monomer for synthesizing polyimide according to one exemplary embodiment, it is possible to reduce the density of the [pi] electrons, Substituents having strong electronegativity such as fluorine (F), sulfonic group (-SO ₂ ) and ether group (-O-) such as trifluoromethyl (-CF ₃ ) By lowering the resonance effect, the transparency polyimide can be obtained by lowering the CTC of the polyimide molecule. Transparency Dielectric and Transparent Diamine for Producing Transparent Polyimide The following transparent dianhydrides and transparent diamines including those exemplified in Formula (1) may be used.

For example, the transparency dianhydride may be selected from the group consisting of PMDA (dianhydride derived from X1 in Formula 1), BPDA (dianhydride derived from X2 in Formula 1), ODPA (dianhydride derived from X3 in Formula 1), BTDA ), DSDA (dihydrate derived from X5 of Formula 1), 6FDA (anhydride derived from X6 of Formula 1), CBDA (dianhydride derived from X7 of Formula 1), CHDA (X8 derived anhydride of Formula 1), BPADA, And the present invention is not limited thereto.

On the other hand, the transparent diamine may be a diamine represented by the following general formula (1): PPD (Y1 derived diamine of formula (1), ODA (Y2 derived diamine of formula (1)), biphenyl diamine, TFMP Derived diamine), MDA, CHDAM, DNBN, 6FBAPP, BAPS, and combinations thereof, but the present invention is not limited thereto.

In order to synthesize the porous polyimide core 322, a pore inducing material is added to the polyamic acid solution and dispersed in the polyamic acid (PAA) synthesized by the above-described method. As the porosity inducing material, for example, polymetal methacrylate (PMMA) and / or lithium chloride may be used. For example, it may be dissolved in an organic solvent such as N, N-dimethylacetamide (DMAc), N, N-dimethyfformamide (DMF), N-methylpyrrolidinone (NMP) The pore inducing material is dissolved and dispersed to obtain a mixed solution. Subsequently, the mixed solution is precipitated in alcohol (C ₁ -C ₅ alcohol such as methyl alcohol), glycol ((di-tri) ethylene glycol, (di- tri) propylene glycol) or acetone.

Dispersion with an organic solvent such as N, N-dimethylacetamide (DMAc), N, N-dimethyfformamide (DMF), N-methylpyrrolidinone (NMP) And a solvent such as alcohol or acetone is repeated, the porous structure having a plurality of pores 324 formed on the surface of the polyamic acid can be obtained while being permeated and removed on the surface of the polyamic acid of the pore inducing material.

Then, the obtained polyamic acid is subjected to a chemical imidization process and a heat treatment process to obtain a polyimide. In the chemical imidization process, a dehydrating agent, such as acetic anhydride, and a dehydrating agent, such as isoquinoline, beta-picoline, or the like, are added to the polyamic acid solution synthesized as a precursor (shell having no pore structure (imides and catalysts represented by tertiary amines such as β-picoline and pyridine) are used.

On the other hand, in the thermal imidation method, the precursor polyamic acid solution is heat-treated at about 250 to 300 캜 and thermally imidized. The polyimide can be obtained by the chemical imidization method and the thermal imidization method in parallel.

In order to obtain the porous polyimide core 322 and the nano organic particles 320 having the polyimide shell 326 structure surrounding the core, the porous polyimide core is first obtained by the above-described method. Then, the porous polyimide particles are dispersed in an organic solvent such as DMAc, DMF or NMP, mixed with a non-pore-treated polyamic acid solution, and precipitated in an organic solvent such as alcohol or acetone to obtain a polyamic acid having a core- Nanoparticles can be obtained. The polyamic acid nanoparticles of the core-shell structure can be heat-treated to obtain the porous core and the polyimide nanoparticles of the non-porous shell. For the conversion of the core-shell structure of polyamic acid nanoparticles to the core-shell structure of polyimide nanoparticles, at a temperature of about 250 to 500 DEG C, preferably 250 to 400 DEG C, more preferably 250 to 350 DEG C Polyamic acid can be heat treated.

[Adhesive film and display device]

As described above, the porous core synthesized according to the present invention and the polyimide constituting the shell are basically excellent in heat resistance. In addition, since the porous structure has good elasticity, the displacement amount and the restoration amount due to the external impact are excellent. Also, the inner-UV characteristics are excellent due to the reflection characteristic and the scattering characteristic caused by the porous structure. Accordingly, the organic nanoparticles composed of the porous polyimide (PI) core synthesized according to the present invention and the polyimide (PI) shell surrounding the core are excellent in heat resistance, good displacement amount and recovery amount, Lt; / RTI >

[First Embodiment]

According to the first embodiment of the present invention, the organic nanoparticles described above can be dispersed in an optical transparent adhesive interposed between the display panel and the cover window. 5 illustrates an example in which an adhesive film 300 comprising an optical transparent adhesive (OCR) in which organic nanoparticles 320 are dispersed in a binder 310 is applied to the display panel 200 and the cover window 400 And FIG. 5 is a cross-sectional view schematically showing a display device 100 applied between the display devices. The cover window 400 is located outside the image display side of the display panel 200 to be described later and transmits the image of the display panel 200 as it is and protects the display panel 200 from external impact or stress. do. The cover window 400 may be injection molded from a material such as tempered glass or reinforced plastic, for example, by an in-mold lamination method or a co-extrusion method. When the flexible characteristic is required, the cover window 400 may be made of a plastic material.

The adhesive film 300 according to the present embodiment positioned between the display panel 200 and the cover window 400 includes the organic nanoparticles 320 dispersed in the binder 310 forming the crosslinking of the network structure . The organic nanoparticles 320 are composed of a core 322 having pores 324 forming a porous structure and a shell 326 surrounding the core 322.

At this time, the adhesive film 300 according to the present embodiment can be produced from a liquid composition for forming an adhesive in which a reactive component that can be cured with a resin and organic nanoparticles 320 are dispersed in a solvent. When the reactive component is thermally cured and / or photocured to form a network structure, the organic nanoparticles 320 are dispersed in the binder 310 of the network structure to form a doped adhesive film 300.

For example, the thermosetting can be carried out using a hot plate and can be carried out at a temperature of about 80 to 150 DEG C, preferably 100 to 120 DEG C for 5 to 20 minutes. On the other hand, photo-curing can be carried out by irradiating light (using a UV lamp or an LED lamp) with a light intensity of approximately 1000 to 5000, preferably 2500 to 4000 mJ / cm 2, and can be performed for several seconds.

The liquid composition for forming an adhesive containing the organic nanoparticles 320 may be coated on one side of the cover window 400 through various coating methods. For example, the liquid composition for forming an adhesive may be applied by roll coating, spin coating, deep coating, flow coating, and spray coating methods And may be coated on the cover window 400 by using the adhesive. In one exemplary embodiment, a slit coating or a flow coating can be used to form a liquid-phase adhesive layer by coating to a thickness of about 100 to 200 [mu] m.

In one exemplary embodiment, the binder 310 may be selected from the group consisting of (meth) acrylate based resins, urethane based resins, rubber based resins, siloxane based resins, combinations thereof, and copolymers thereof. Unless otherwise stated herein, the term (meth) acrylate refers to both acrylate and (meth) acrylate.

For example, when a (meth) acrylate resin is used as the binder 310, the liquid composition for forming an adhesive may contain a photoreactive component which can be cured by irradiation with an appropriate light source as a reactive component and / Lt; RTI ID = 0.0 > thermally reactive < / RTI >

The (meth) acrylate-based reactive component may comprise a monomer or oligomer having an ethylenic double bond. In one exemplary embodiment, the (meth) acrylate-based reactive component may use a (meth) acrylate-based reactive component having no more than two acrylic functionalities. When a (meth) acrylate-based reactive component having three or more acrylic functional groups is used, the shrinkage rate during the curing process is too large to cause defects such as yellow mura.

According to an exemplary embodiment, the (meth) acrylate-based reactive components are C ₁ ~ C ₂₀ alkyl group, C ₂ ~ C ₂₀ alkenyl group, C ₂ ~ C ₂₀ alkynyl group, C ₁ ~ C ₂₀ alkoxy group, C ₁ An aliphatic (meth) acrylate-based reactive component substituted with a C ₁ -C ₂₀ alkoxyalkyl group, a C ₁ -C ₂₀ alkoxy allyl group, an epoxy group, or the like; C ₅ -C ₈ cycloalkyl (meth) acrylates which are unsubstituted or substituted by C ₁ -C ₁₀ alkyl groups, C ₂ -C ₁₀ alkenyl groups, C ₂ -C ₁₀ alkynyl groups, or C ₁ -C ₁₀ alkoxy groups Rate-based reactive component; Unsubstituted or C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl group, aryl (meth) acrylates of C ₂ -C ₁₀ alkynyl group, or a C ₁ C ₅ ~ C ₂₀ in -C ₁₀ alkoxy substituted with a Based reactive component; An allyl alkoxylate-reactive component having a C ₁ -C ₂₀ alkoxy group; And combinations thereof. For example, the (meth) acrylate-based reactive component may be a C ₁ -C ₁₀ alkyl group, a C ₂ -C ₁₀ alkenyl group, a C ₁ -C ₂₀ alkoxy group, a C ₁ -C ₁₀ alkoxyalkyl group or a C ₁ -C ₁₀ alkoxy (Meth) acrylate-based monomer and / or oligomer having an allyl group, and / or an allyl alkoxylate-based monomer and / or oligomer having a C ₁ -C ₁₀ alkoxy group.

For example, the C ₁ -C ₂₀ alkyl (meth) acrylate reactive component may be selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) acrylate, heptyl (meth) acrylate, isobutyl (meth) acrylate, isobutyl (meth) acrylate, (Meth) acrylate, iso-octyl (meth) acrylate, n-octyl (meth) acrylate, (Meth) acrylate, isooctyl (meth) acrylate, n-dodecyl (meth) acrylate, isododecyl (Meth) acrylate, and combinations thereof. However, the present invention is not limited thereto Do not.

The C ₂ -C ₂₀ alkenyl (meth) acrylate-based reactive component may be selected from the group consisting of octadiene (meth) acrylate, octadiene (meth) diacrylate and combinations thereof, But is not limited thereto.

The C ₁ -C ₂₀ alkoxy (meth) acrylate reactive component includes butadiene (meth) acrylate, hexadiene (meth) acrylate; (Meth) acrylate such as 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, ethylene glycol methyl ether (meth) acrylate, ethylene glycol phenyl ether (Meth) acrylate, diethylene glycol ethyl ether (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene glycol di Diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, and combinations thereof, but the present invention is not limited thereto.

The C ₁ -C ₂₀ alkoxyalkyl (meth) acrylate reactive component is selected from the group consisting of 2-hydroxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, Acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, trimethoxybutyl Group, but the present invention is not limited thereto.

The epoxy (meth) acrylate-based reactive component may be selected from the group consisting of epoxy (meth) acrylate, epoxycyclohexylmethyl (meth) acrylate, glycidyl (meth) acrylate, methylglycidyl And the present invention is not limited thereto.

The C ₅ -C ₈ cycloalkyl (meth) acrylate-based reactive component is selected from the group consisting of cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl But the present invention is not limited thereto.

The C ₅ -C ₂₀ aryl (meth) acrylate-based reactive component is selected from the group consisting of benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, 2-hydroxy- And the like, but the present invention is not limited thereto.

The allyl alkoxylate-based reactive component may be selected from the group consisting of allyl propoxylate, allyl monopropoxylate, and combinations thereof, but the present invention is not limited thereto.

The (meth) acrylate oligomer that can be used as a reactive component controls physical properties such as the softness of the (meth) acrylate cage resin. As the (meth) acrylate oligomer component, two or more oligomer components having different molecular weights may be used in combination. For example, physical properties can be effectively controlled by using a first oligomer having a weight average molecular weight of 500 to 900 and a second oligomer having a weight average molecular weight of 1000 to 10000, preferably in the range of 1000 to 5000 in combination. Alternatively, a first oligomer having a weight average molecular weight of 500 to 3000 and a second oligomer having a weight average molecular weight of 4000 to 50,000 may be used in combination.

In an exemplary embodiment, the (meth) acrylate-based oligomer may be contained in a proportion of 30 to 70 parts by weight, preferably 40 to 60 parts by weight, in the liquid composition for forming an adhesive. Unless otherwise stated herein, parts by weight refer to weight ratios between the components being compounded. If the content of the (meth) acrylate oligomer is less than 30 parts by weight in the liquid composition for forming an adhesive, the content of the (meth) acrylate-based monomer described later increases due to the decrease in viscosity, so that it is difficult to control the physical properties. On the other hand, when the content of the (meth) acrylate oligomer exceeds 70 parts by weight, the viscosity becomes too high, which may cause problems in the curing reaction rate and viscosity control.

In one exemplary embodiment, the liquid composition for forming an adhesive may further comprise a (meth) acrylate-based monomer. For example, the (meth) acrylate-based monomer which is a photoreactive component is for controlling the reaction rate and viscosity. As the photoreactive component, the (meth) acrylate monomer is contained in a proportion of 5 to 20 parts by weight in the liquid composition for forming an adhesive. If the content of the (meth) acrylate monomer is less than 5 parts by weight, the viscosity of the liquid composition for forming an adhesive becomes excessively low, so that it is difficult to uniformly coat the liquid composition for forming an adhesive on the cover window 400. If the content of the (meth) acrylate monomer exceeds 20 parts by weight, the curing reaction rate may be slowed down.

The liquid composition for forming an adhesive to be cured by the binder 310 includes a photopolymerization initiator to induce a photopolymerization reaction of a reactive component such as (meth) acrylate, which may be a photoreactive component, for example. For example, the photopolymerization initiator may be any photopolymerization initiator capable of inducing a photopolymerization reaction of the (meth) acrylate-based reactive component by irradiation with an appropriate light source such as UV. For example, commercial photopolymerization initiators, which may be composed of Irgacure 184, Irgacure 819, and combinations thereof, may be used, but the photopolymerization initiators that may be used in accordance with the present invention are by no means limited to these products.

Examples of usable photopolymerization initiators include 1) 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyltrichloroacetophenone, acetophenone based photopolymerization initiators such as p-tert-butyldichloroacetophenone, 4-chloroacetophenone and 2,2'-dichloro-4-phenoxyacetophenone, 2) benzophenone, 4,4'-dimethylaminobenzophenone, 4 , 4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4,4'-bis (dimethylamino) Benzophenone-based photopolymerization initiators such as 4,4'-bis (diethylamino) benzophenone, and 3) benzophenone-based photopolymerization initiators such as thioxanthone, 2-crothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 1- 9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- (O- acetyloxime), 2,4- diethylthioxanthone, Propyl thioxanthone, 2-chlorothioxanthone, and the like 4) benzoin-based photopolymerization initiators such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether and benzyl dimethyl ketal; 5) 4,6-trichloro (trichloromethyl) -6-styryl-s-triazine, 2-phenyl-4,6-bis (trichloromethyl) (4'-methoxystyryl) -6-triazine, 2- (3 ', 4'-dimethoxystyryl) -4, (Trichloromethyl) -s-triazine, 2- (4-methoxynaphthyl) -4,6-bis (trichloromethyl) ) -4,6-bis (trichloromethyl) -s-triazine, and 2-phenyl-4,6-bis (trichloromethyl) -s-triazine.

The photopolymerization initiator may be contained in a proportion of 0.01 to 10.0 parts by weight in the liquid composition for forming an adhesive. If the content of the photopolymerization initiator is less than 0.01 part by weight, the curing reaction rate of the (meth) acrylate-based reactive component becomes too slow or the curing efficiency becomes poor due to failure to perform the initiating function. If the content of the photopolymerization initiator exceeds 10.0 parts by weight, yellowing may be caused due to the ring structure characteristic of the photopolymerization initiator not participating in the curing.

Although the (meth) acrylate-based reactive component has been described above as a reactive component for forming the binder 310, a reactive component for forming other types of binders may also be used. According to an exemplary embodiment, when a urethane-based resin or a urethane (meth) acrylate-based resin is used as the binder 310, a urethane prepolymer obtained by reacting a polyol and a diisocyanate to form a urethane bond is used as a reactive component .

The polyol for synthesizing the urethane prepolymer may be a polyol obtained by reacting ethylene oxide or propylene oxide with glycerin, or a polyether polyol such as propylene glycol, tetramethylene glycol or ethylene glycol polyether; And / or polycaprolactone polyol, a polyester polyol obtained by dehydration condensation reaction of glycol or triol in adipic acid which is a dibasic acid, and the like.

The diisocyanate compound for synthesizing the urethane prepolymer may be at least one selected from toluene diisocyanate (TDI), methylenediphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI) . After reacting these isocyanates with a polyol to synthesize an urethane prepolymer, a polyurethane bond can be obtained by conducting a moisture curing process.

On the other hand, the rubber-based resin may be a polybutadiene (PB) resin, a polyisobutylene (PIB) resin, a polypentadiene resin, a polyisoprene resin, a polyneoprene resin, Butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), acrylonitrile-butadiene-styrene (ABS) resin, acrylate-butadiene rubber -Butadiene rubber, ABR, ethylene-propylene rubber, ethylene-propylene-diene rubber, combinations thereof, and copolymers thereof. In order to produce such a rubber-based resin, monomers and / or oligomers composed of the above-mentioned rubber-based resin unit may be used as a reactive component. Monomers and / or oligomers having a diene structure are preferably used.

On the other hand, when the siloxane-based resin is used, the siloxane monomer and / or the siloxane oligomer as the reactive component constituting the main chain of the siloxane-based resin are not particularly limited. In an exemplary embodiment, the siloxane monomer and / or siloxane oligomer may or may not have photoreactive functional moieties attached to the side chain. Examples of siloxane monomers and / or siloxane oligomers include silanol monomer / oligomer or siloxane monomer / oligomer having at least one silanol group and / or siloxane group.

The silanol monomer / oligomer may be an ethylenically unsaturated alkoxysilane or an ethylenically unsaturated acyloxysilane. The ethylenically unsaturated alkoxysilane compound is preferably selected from the group consisting of an acrylate alkoxysilane (e.g.,? -Acryloxypropyl-trimethoxysilane,? -Acryloxypropyl-triethoxysilane), a methacrylate alkoxysilane Methacryloxypropyl-triethoxysilane), and the like. Examples of the ethylenically unsaturated aryloxysilane compound include acrylate-based acetoxysilane, methacrylate-based acetoxysilane, and ethylenically-unsaturated acetoxysilane (for example, acrylatepropyltriacetoxysilane, methacrylatepropyltriacetate Ethoxy silane).

On the other hand, as the siloxane monomer and / or siloxane oligomer for forming the main chain of the siloxane-based resin, a monomer / oligomer having a siloxane group can also be used. Examples of the monomer / oligomer having a siloxane group include a siloxane monomer / oligomer having a linear siloxane group, a cyclosiloxane monomer / oligomer, a tetrahedral siloxane monomer / oligomer, and a monomer / oligomer having a silsesquioxane structure.

The monomer / oligomer compound having a linear siloxane is C ₁ -C ₁₀ alkyl and / or C ₁ -C ₁₀ alkoxy group is an alkyl siloxane, an alkoxy siloxane with substitutions, alkoxy alkyl siloxanes, vinyl alkoxy siloxane, 3-aminopropyl of But are not limited to, ethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3- methacryloxypropyl Trimethoxysilane, 3-mercaptopropyltrimethoxysilane, and the like, or a mixture of two or more selected from these may be used, but the present invention is not limited thereto.

On the other hand, the siloxane monomer / oligomer having a cyclosiloxane group may be substituted with a C1-C10 alkyl group such as a C1-C20 alkyl group, preferably a methyl group or an ethyl group, with the siloxane group constituting the repeating unit. In this case, the polyalkylcyclosiloxane resin in which the cyclosiloxane group constitutes a repeating unit may be a polydialkylsiloxane in which two alkyl groups are substituted for each of the silicon atoms, for example, a cyclic siloxane resin of polydimethyl siloxane (PDMS) . ≪ / RTI >

In a non-limiting embodiment, the cyclosiloxane resin comprises methyl hydrocyclo siloxane; Hexa-methylcyclotrisiloxane; Hexa-ethyl cyclotrisiloxane; Tetra-, penta-, hexa-, octa-methyl cyclotetrasiloxane; Tetra-ethylcyclotetrasiloxane; Tetra-octylcyclotetrasiloxane; Tetra-, penta-, hexa-, oxa- and deca-methyl cyclopentasiloxanes; Tetra-, penta-, hexa-, oxa- and dodeca-methyl cyclohexasiloxanes; Tetradeca-methylcycloheptasiloxane; Hexadeca-methyl cyclooctasiloxane; Tetraphenylcyclotetrasiloxane; And combinations thereof.

Further, non-limiting examples of the monomer having a tetrahedral siloxane group include tetrakisdimethylsiloxysilane, tetrakis diphenylsiloxysilane and tetrakisdiethylsiloxysilane, and mixtures thereof.

In addition to the linear, cyclic and tetrahedral siloxanes, silsesquioxane (SSQ), which can be synthesized by, for example, reaction of methyltrichlorosiloxane with dimethylchlorosiloxane, is used as a reactive component for synthesizing a siloxane resin . Silsesquioxane can be synthesized by crosslinking with polysilsesquioxane having a ladder structure or a cage structure. For example, by hydrolysis of organotrichlorosilane, a heptamer type siloxane of partial cage structure, a heptamer type of cage structure, and an octamer type siloxane can be obtained. By using solubility difference, Silsesquioxane monomer can be obtained by the condensation reaction of organotrialkoxysilane or organotrichlorosilane. Silsesquioxanes about the chemical structure of RSiO _3/2 (R is a C5 ~ C20 aryl group such as hydrogen, C1 ~ C10 alkyl group, C2 ~ C10 alkenyl group, a phenyl), but may have a thread that can be used in the present invention Sesquioxane is not limited thereto. When a silsesquioxane monomer / oligomer having a silsesquioxane structure is used, it is possible to form a polyhedral oligomeric silsesquioxane (POSS) having a ladder-type or cage-type structure excellent in heat resistance, Hexane and hexane.

In an alternative embodiment, the liquid composition for forming an adhesive may include a tackifier to improve adhesion to the display panel 200 and / or the cover window 400. The pressure sensitive adhesive can be a hydrogenated C ₅ pressure-sensitive adhesive which is reduced in color through a hydrogenation reaction and improved in stability against heat, oxygen and ultraviolet rays. As the pressure-sensitive adhesive, one having a specific gravity smaller than that of the binder 310 synthesized by curing the photoreactive component or the heat-reactive component can be used

Adhesives which may be used may be selected from the group consisting of, for example, isoprene, piperylene, cyclopentadiene, cyclopentene and combinations thereof. Especially preferred are isoprene, trans-1,3-pentadiene, cis-1,3-pentadiene, 2-methyl-2-butene and combinations thereof. They can move to the interface of the display panel 200 side or the cover window 400 side in the process of photocuring or thermosetting to improve the adhesion to the display panel 200 and / . Illustratively, the pressure-sensitive adhesive may be compounded in a proportion of 0.1 to 20 parts by weight in the liquid composition for forming an adhesive.

Optionally, the liquid composition for forming an adhesive, which is cured with the binder 310, comprises a plasticizer component suitable for modulating the modulus of the adhesive film 300. The plasticizer component that may be used includes any component that can lower the modulus of the adhesive layer. For example, the plasticizer component may be a dioctyl phthalate (DOP) type, a dioctylaminate (DOA) type, a tricresylphosphate (TCP), a dioctyl azoleate (DOZ) type, an ester (Esther) type, a polyisoprene type And combinations thereof. The plasticizer component is compounded in a proportion of 30 to 70 parts by weight in the adhesive layer.

If the content of the pressure-sensitive adhesive component is less than 0.1 parts by weight, it is difficult to expect an improvement in adhesion to the object to be adhered. On the other hand, if the content of the plasticizer component is less than 30 parts by weight, the modulus of the adhesive may be excessively high. If the content of the adhesive is more than 20 parts by weight or the content of the plasticizer component is more than 70 parts by weight, the content of the photoreactive and thermoreactive components in the adhesive film 300 may be lowered and the curing reaction rate may be slowed down. Also, the adhesive agent and the plasticizer component, which are unreacted components in the binder matrix 310 having a low curing density, are increased, so that adhesion failure may occur.

The adhesive film 300 according to the exemplary embodiment of the present invention includes a polyimide (PI) core 322 having a porous structure having a plurality of pores 324 in the binder 310 of the network structure described above, The organic nanoparticles 320 composed of the polyimide shell 326 surrounding the polyimide shells 322 are dispersed. The organic nanoparticles 320 are polyimide components having excellent heat resistance. By including the organic nanoparticles 320, the heat resistance characteristics of the adhesive film 300 can be improved, and the storage modulus and the tensile modulus due to the external impact due to the temperature change of the adhesive film 300 can be prevented from changing abruptly can do. Therefore, as shown in FIG. 6A, the adhesive film 300 in which the organic nanoparticles 320 are dispersed is improved in heat resistance, so that the network structure of the binder 310 is not collapsed even in a high temperature environment or high temperature / So that the adhesive force can be maintained.

On the other hand, the core 322 of the organic nanoparticles 320 has a porous structure having a plurality of pores 324 and is excellent in elasticity. Therefore, as shown in FIG. 6B, since the displacement characteristics and restoration characteristics of the adhesive film 300 in which the organic nanoparticles 320 are dispersed are improved, an excellent restoring force can be maintained even by external pressure.

At this time, the organic nanoparticles 320 may be dispersed in a proportion of 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight, in the liquid composition for forming an adhesive and / or the adhesive film 300 produced therefrom. If the content of the organic nanoparticles 320 is less than the above-mentioned range, it is difficult to expect improvements in physical properties such as heat resistance, restoring force, and inner-UV characteristics upon addition of the organic nanoparticles 320. If the content of the organic nanoparticles 320 exceeds the above range, the organic nanoparticles 320 may aggregate during the curing process, so that the organic nanoparticles 320 may not be uniformly dispersed in the binder 310 , Excessive light scattering may occur and the transmittance of the display device may be reduced.

As described above, according to the exemplary embodiment of the present invention, the organic nanoparticles 320 can be utilized as the adhesive film 300 in which the binder 310 is dispersed. Can be applied as an optical transparent adhesive between the cover window (400). The adhesive film 300 in which the organic nanoparticles 320 according to the present invention are dispersed is excellent in heat resistance and does not deteriorate under high temperature and / or high temperature and high humidity conditions. And can be applied to attach the peripheral members to be joined together. In particular, the adhesive film 300 in which the organic nanoparticles 320 are dispersed according to the present embodiment does not cause yellowing that is discolored into yellow light even by ultraviolet rays generated in a curing process or irradiation of external light, And even if it is used as an optical transparent adhesive layer, the optical properties such as light transmission characteristics are not impaired and good quality can be maintained.

Subsequently, a display device having the adhesive film 300 in which the organic nanoparticles 320 are dispersed in the binder 310 according to an exemplary embodiment of the present invention will be described in more detail. 7A is a cross-sectional view schematically showing a display device to which an adhesive film in which organic nanoparticles are dispersed is applied according to an exemplary embodiment of the present invention. 7A, the display device 100A mainly includes a display panel 200, a cover window 400 positioned outside the display panel 200, a display panel 200 and a cover window 400, And an adhesive film 300 interposed therebetween. The display panel 200 may include a liquid crystal display panel, an organic light emitting display panel employing an organic light emitting diode, and any display panel capable of displaying an image.

Meanwhile, the cover window 400 may include a central substrate 410 and a hard coating layer 412, 414 for reinforcing the substrate 410. The substrate 410 can be made of tempered glass, but can be made of plastic if it is desired to implement a flexible display. The plastic substrate 410 constituting the cover window 400 may be made of a material selected from the group consisting of polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), polycarbonate (PC), polycarbonate-polymethylmethacrylate (PC- (PMMA-PC-PMMA), and the like, and they can be produced by a method of (co) extruding these polymer materials.

Generally, since the cover window 400 is located at the outermost portion of the display device 100A, wear resistance is required to prevent external scratches including nails and touch pens. Therefore, the impact resistance should be improved so as to prevent the cover window 400 from being broken by an external impact. For this purpose, a rigid first hard coating layer 412 and a second hard coating layer 414 are formed on the upper and lower portions of the plastic substrate 410, respectively.

When the coating is applied to only one side of the plastic substrate 410, it is preferable that the plastic substrate 410 is warped and the hard coat layer having the same thickness is coated on the opposite side. For example, the hard coating layers 412 and 414 may be prepared using urethane acrylic resins, methacrylic resins, silsesquioxane compounds, and the like, and may be applied by roll-coating, spin-coating, dip- Spray-coating, or the like. The compound may be coated on the substrate 410 and cured by UV or the like to form the hard coat layers 412 and 414. [ For example, the overall thickness of the cover window 400 may be approximately 0.5 to 1.0 mm, and the hard coat layers 412 and 414 may each be formed to a thickness of 5 to 40 占 퐉, but the present invention is not limited thereto.

The adhesive film 300 interposed between the display panel 200 and the cover window 400 may be formed of, for example, a (meth) acrylate resin, a urethane resin, a rubber resin, a siloxane resin, The organic nanoparticles 320 are dispersed in the binder 310, which may be a binder. Since the heat resistance of the adhesive layer 300 can be improved by dispersing the organic nanoparticles 320, the adhesive film 300 can be prevented from being deformed in a high temperature environment or a high temperature / high humidity environment. Further, in the display device to which the pressure sensitive type touch panel (see, for example, reference numeral 290 in FIG. 7B) is applied, which includes the polyimide nanoparticles 320 having excellent displacement characteristics and restoration characteristics, displacement characteristics The restoration characteristic can be improved. In addition, since the polyimide nanoparticles 320 are excellent in the inner-UV characteristics, in the case of the adhesive film 300 in which the polyimide nanoparticles 320 are dispersed, yellowing due to UV irradiation is not caused. Therefore, excellent light transmittance can be maintained, and the adhesive force is not lowered due to yellowing.

7B shows a display device 100C in which a touch panel 290, which is also referred to as a touch screen panel, is placed between the display panel 200 and the adhesive film 300, Respectively. 7B, the touch panel 290 exemplifies an on-cell type located on the display panel 200. However, the touch panel 290 may include an in-cell type (in-cell type).

As described above, the display panel 200 may be a liquid crystal display panel or an organic light emitting diode display panel. 8 is a cross-sectional view schematically showing a display panel 200 made of, for example, a liquid crystal display panel of a transverse electric field system.

One substrate 201 and the second substrate 202 are opposed to each other in the display panel 200 and a liquid crystal layer 230 is interposed between the substrates 201 and 202. The first substrate 201 and the second substrate 202 may be a glass substrate, a thin flexible substrate, or a polymer plastic substrate. An alignment film for determining the initial alignment direction of the liquid crystal is formed at the boundary between the first substrate 201 of the display panel 200 and the liquid crystal layer 230 of the second substrate 202, A seal pattern (not shown) is formed along the edges of the first substrate 201 and the second substrate 202 to prevent leakage of the liquid crystal layer 230. First and second polarizing plates 212 and 214, which selectively transmit only specific light, are attached to the outer surfaces of the first and second substrates 201 and 202, respectively. The first polarizing plate 212 and the second polarizing plate 214 transmit only the linearly polarized light parallel to the respective light transmission axes and the light transmission axis of the first polarizing plate 212 and the light transmission axis of the second polarizing plate 214 Are arranged vertically.

A plurality of electrodes and wirings stacked on the first substrate 201 will be described in more detail. A plurality of gate lines (not shown) extend in a first direction on the first substrate 201. A plurality of pixel regions P are defined by intersecting the plurality of gate lines (not shown) A plurality of data wirings 270 are formed. A gate pad (not shown) is formed in the non-display region and connected to one end of the data line 270 to form a data pad (not shown) in the non-display region .

A semiconductor layer 266 including a gate electrode 262, a gate insulating film 263, an active layer 266a, an ohmic contact layer 266b, and a source electrode 272 are formed in each of the plurality of pixel regions P, , And 274 are formed on the substrate. The gate electrode 262 is connected to a gate wiring (not shown) and is formed on the first substrate 201. A gate insulating film 263 made of an inorganic insulating material such as silicon oxide (SiOx) or silicon nitride (SiNx) is formed on the gate wiring (not shown) and the gate electrode 262. [

A semiconductor layer 266 is formed on the gate insulating film 263 in correspondence with the gate electrode 262. For example, the semiconductor layer 266 may include an active layer 266a made of intrinsic amorphous silicon, an active layer 266b formed on the active layer 266a and exposed to the center of the active layer 266a and doped with an impurity doped amorphous And an ohmic contact layer 266b made of silicon (impurity doped amorphous silicon).

A source electrode 272 and a drain electrode 274 are formed on the semiconductor layer 266 to expose the center of the active layer 266a. The source electrode 272 is located on the semiconductor layer 266 and extends in the data line 270 and the drain electrode 274 is spaced apart from the source electrode 272 on the semiconductor layer 266. The thin film transistor Tr is located in the switching region TrA.

The gate electrode 262, the semiconductor layer 266, the source electrode 272 and the drain electrode 274 constitute a thin film transistor Tr and an active layer 266a exposed between the source and drain electrodes 272 and 274 Is a channel of the thin film transistor Tr.

7, the thin film transistor Tr includes a semiconductor layer 266 having a gate electrode 262 disposed under the semiconductor layer 266 and source and drain electrodes 272 and 274 disposed above the semiconductor layer 266, staggered structure. Alternatively, the thin film transistor may have a coplanar structure in which the gate electrode and the source and drain electrodes are located on top of the semiconductor layer. In this case, the semiconductor layer may be made of polycrystalline silicon, and impurities may be doped on both sides of the semiconductor layer. On the other hand, the semiconductor layer may be made of an oxide semiconductor, and in the case of an inversely staggered structure, the ohmic contact layer may be omitted.

On the gate insulating film 263, a data line 270 extending along the second direction is formed so as to intersect the gate line (not shown). The data line 270 extends from the source electrode 272 of the thin film transistor Tr located in the pixel region P. [ On the other hand, common wiring (not shown) is formed along the second direction parallel to the data wiring 270 on the gate insulating film 263, and crosses the gate wiring (not shown). In an alternative embodiment, the common wiring (not shown) may be formed in the same layer as the gate wiring (not shown) in parallel with the gate wiring (not shown).

On the other hand, a first passivation layer 264 covering the data line 270, the source electrode 272, the drain electrode 274 and the common line (not shown) is formed. A drain contact hole 275 is formed in the first passivation layer 264 to expose the drain electrode 272 of the thin film transistor Tr. The first protective layer 264 may be formed of an organic insulating material such as an inorganic insulating material such as silicon or acrylic photo oxide (SiO ₂₎ or silicon nitride (SiNx). The first passivation layer 264 prevents the ohmic contact layer 266b from being damaged in the process of forming the pixel electrode 280. [

A pixel electrode 280 as a first electrode which is in contact with and electrically connected to the drain electrode 274 of the thin film transistor Tr through the drain contact hole 275 is formed in each pixel region P, (Not shown). The pixel electrode 280 is made of a transparent conductive material and may have a plate shape in each pixel region P. [ For example, the transparent conductive material may be indium-tin-oxide (ITO) or indium-zinc-oxide (IZO). Although not shown, a gate pad electrode and a data pad electrode made of the same transparent conductive material as the pixel electrode 280 are formed in the non-display region of the upper portion of the first passivation layer 264, And is electrically connected to the gate pad through a pad contact hole (not shown), and the data pad electrode is electrically connected to the data pad through a data pad contact hole (not shown).

A second passivation layer 276 is formed on the pixel electrode 280. Like the first passivation layer 264, the second passivation layer 276 may be formed of an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx) or an organic insulating material such as photoacryl.

On the other hand, a common electrode 290 having a plurality of slit-shaped holes (openings 292) is formed on the second passivation layer 276, overlapping the plate-shaped pixel electrode 280. Like the pixel electrode 280, the common electrode 290 as the second electrode may be made of a transparent conductive material such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO). The common electrode 290 is formed on the entire surface of the display region where a plurality of pixel regions P are formed. When a voltage is applied between the pixel electrode 280, which may be a first electrode in a plate form, and the common electrode 290, which may be a second electrode having an opening 292, a fringe field is formed, By driving, the transmission efficiency is improved and a high-quality image is displayed.

Although not shown in the drawings, a black matrix, which is a light shielding member having an opening corresponding to each pixel region P, is formed below the second substrate 202 constituting the color filter substrate, and a lower portion of the black matrix and a black matrix A color filter layer is formed under the second substrate 202 exposed through the opening. The color filter layer (not shown) includes red (R), green (G), and blue (B) color filters corresponding to the pixel regions P. An overcoat layer (not shown) of a material such as polyimide, polyacrylate, or polyurethane is formed between the color filter layer (not shown) and the liquid crystal layer 230 in order to protect the color filter layer (not shown) Can be formed.

When the thin film transistor Tr selected for each gate wiring (not shown) is turned on by the ON / OFF signals of the gate driving circuit, the display panel 200 displays the signal voltage of the data driving circuit The alignment direction of the liquid crystal molecules is changed by the electric field between the pixel electrode 280 and the common electrode 290 and the difference in transmittance is exhibited.

On the other hand, polarizers 212 and 214, which selectively transmit only specific light, are attached to the outer sides of the first substrate 201 and the second substrate 202, respectively. In addition, a backlight unit may be provided to supply light from the rear surface of the transflective liquid crystal display panel 200 so that a difference in transmittance represented by the transflective liquid crystal display panel 200 is externally expressed. 7A and 7B) sandwiched between the polarizing plate 214 attached to the outside of the second substrate 202 and the cover window 400 (see Figs. 7A and 7B) The display panel 200 is bonded together.

According to the first embodiment of the present invention, organic nanoparticles 320 (see FIG. 4) made of a porous polyimide core 322 (see FIG. 4) and a non-porous polyimide cell 326 The adhesive film 300 dispersed in a resin that can form a transparent adhesive has excellent heat resistance characteristics and is low in modulus and is flexible. Since the heat resistance of the adhesive film 300 can be improved by dispersing the organic nanoparticles 320, the adhesive film 300 can be prevented from being deformed in a high temperature environment or a high temperature and high humidity environment.

Further, in the display device to which the pressure sensitive type touch panel (see, for example, reference numeral 290 in FIG. 7B) is applied, which includes the polyimide nanoparticles 320 having excellent displacement characteristics and restoration characteristics, displacement characteristics The restoration characteristic can be improved. Furthermore, since the UV-V characteristics are excellent, yellowing due to UV does not occur. Therefore, excellent adhesive force can be maintained and the light transmission characteristic is not deteriorated, so that a good image quality can be realized.

[Second Embodiment]

In the second embodiment of the present invention, a case where an adhesive film adopting organic nanoparticles is applied between a display panel and a structure supporting the display panel is exemplified. 9 is a cross-sectional view schematically showing a liquid crystal display device to which organic nanoparticles are applied according to an exemplary embodiment of the present invention. 9, a liquid crystal display 500 as a display device according to an exemplary embodiment of the present invention includes a liquid crystal panel 600, a backlight unit 530 as a structure for supporting the liquid crystal panel 600, A main frame 540, a bottom frame 550, and an adhesive film 560.

The liquid crystal panel 600 displaying an image may be the liquid crystal panel shown in Fig. For example, the liquid crystal panel 600 includes a first substrate 601 and a second substrate 602, which are bonded to each other with a liquid crystal layer (not shown) therebetween. A gate printed circuit board and a data printed circuit board (not shown) are connected to at least one edge of the liquid crystal panel 600 via a connection member (not shown) such as a flexible circuit board, thereby modulating the liquid crystal panel 600, In this process, the main frame 540 is brought into close contact with the side surface of the main frame 540 or the back surface of the bottom frame 550. First and second polarizers 612 and 614 are disposed on the outer surfaces of the first and second substrates 601 and 602, respectively. For example, the first and second substrates 601 and 602 may be made of glass or a flexible plastic material.

A backlight unit 530 that is a structure that supports the liquid crystal panel 600 while supplying light to the back surface of the liquid crystal panel 600 is disposed so that the difference in transmittance represented by the liquid crystal panel 600 is externally displayed. The backlight unit 530 includes a light emitting diode assembly 538 arranged along the longitudinal direction of at least one edge of the main frame 540, a white or silver reflection plate 536, A light guide plate 534, and an optical sheet 532 disposed on the light guide plate 534.

The light emitting diode assembly 538 is a light source of the backlight unit 530 and is positioned at one side of the light guide plate 534 so as to face the light entrance surface of the light guide plate 534. The light emitting diode assembly 538 includes a plurality of light emitting diodes 538a and a printed circuit board 538b on which a plurality of light emitting diodes 538a are mounted at a predetermined interval.

The light emitting diode 538a includes a light emitting diode chip (not shown) that emits red (R), green (G), and blue (B) light or emits white light toward the front of the light guide plate 534 , The white light can be emitted forward toward the light incoming surface of the light guide plate 534. In an exemplary embodiment, the plurality of light emitting diodes 538a emit red (R), green (G), and blue (G) light, respectively, and simultaneously light a plurality of light emitting diodes 538a for color- May be realized. In another exemplary embodiment, each light emitting diode 538a may emit white light.

The light guide plate 534 on which the light emitted from the plurality of light emitting diodes 538a is incident is formed such that the light incident from the plurality of light emitting diodes 538a travels in the light guide plate 534 by total reflection several times, So that the liquid crystal panel 600 is provided with a surface light source. The light guide plate 534 may include a pattern of a specific shape on the back surface to supply a uniform surface light source. For example, the pattern of the light guide plate 534 may be an elliptical pattern, a polygon pattern, a hologram pattern, or the like in order to guide light incident into the light guide plate 534 And such a pattern may be formed on the lower surface of the light guide plate 534 by a printing method or an injection method.

The reflection plate 536 is disposed on the back surface of the light guide plate 534 and reflects light passing through the back surface of the light guide plate 534 toward the liquid crystal panel 600 to improve the brightness of light. The plurality of optical sheets 532 on the light guide plate 534 includes a diffusion sheet and at least one light condensing sheet and the like to diffuse or condense the light passing through the light guide plate 534 to form a more uniform surface Allow the light source to enter.

The liquid crystal panel 600 and the backlight unit 530 are modularized through the main frame 540, the bottom frame 550, and the adhesive film 560. The bottom frame 550 on which the backlight unit 530 is mounted includes a horizontal plane on which the whole instrument assembly constituting the liquid crystal display apparatus 500 is based and an edge portion whose edge is vertically bent. The main frame 540 having a rectangular frame shape includes a side wall portion 540a surrounding the side surface of the backlight unit 530 such as the side surface of the light guide plate 534 and the back surface of the printed circuit board 538b, And a support portion 540b that is bent from the upper surface of the backlight unit 530 such as the light guide plate 534 and is disposed above the upper surface edge of the backlight unit 530, The main frame 540 may also be referred to as a support main, guide panel or main support, or a mold frame, and the bottom frame 550 may be referred to as a cover bottom, a bottom cover, or a bottom cover. The main frame 540 and the bottom frame 550 may be made of a material such as polycarbonate (PC), aluminum, stainless steel, Electrolytically Galvanized Steel (EGI) or the like, .

The liquid crystal display 500 includes a display area DR substantially used for image display and a non-display area NDR surrounding the display area DR. The non-display area NDR includes a non-display area called a bezel area, The display area NDR may be defined as an area where the light of the backlight unit 530 can not be supplied to the liquid crystal panel 600 by the support part 540b of the main frame 540. [ The liquid crystal panel 600 is fixed to the support portion 540b of the main frame 540 so that the edges of the liquid crystal panel 600 are supported by the adhesive layer 540b between the liquid crystal panel 600 and the support portion 540b of the main frame 540 560 are formed.

The adhesive film 560 serves to fix the liquid crystal panel 600 to the support portion 540b of the main frame 540. [ The adhesive agent according to the present invention is continuously applied to the four sides of the support portion 540b or the four sides of the liquid crystal panel 600 so that the adhesive film (560) can be formed.

According to an exemplary embodiment of the present invention, an adhesive film 560 interposed between the liquid crystal panel 600 and the main frame 540 comprises a binder and a porous polyimide core 322 (see FIG. 4) dispersed in a binder And organic nanoparticles 320 (see FIG. 4) made of a non-porous polyimide shell 326 (see FIG. 4). The binder constituting the adhesive film 560 can be used in combination with a resin having a soft type, that is, a low modulus, and a resin having a hard type, that is, a high modulus. When the soft type resin is used, the resin may deteriorate under high temperature / high humidity conditions and the adhesion may be deteriorated. When only a hard type resin is used, the impact of the impact is insufficient, 600).

9, the binder constituting the adhesive film 560 to be applied between the liquid crystal panel 600 and the backlight unit 530, more specifically, the main frame 540, A phosphorus (meth) acrylate resin and a hard type urethane resin can be used together. Accordingly, the soft type (meth) acrylate resin is cured by UV or the like, so that the shape of the adhesive film 560 can be maintained even after the liquid crystal panel 600 and the backlight unit 530 are bonded together, and the hard type urethane- A strong adhesive force can be ensured while a constant cell gap between the liquid crystal panel 600 and the backlight unit 530 can be maintained.

According to the exemplary embodiment, when the binder constituting the adhesive film 560 is composed of a (meth) acrylate resin and a urethane resin, they may be a monomer / oligomer (meth) acrylate reactive component described in the first embodiment The network structure is formed by the reaction of polyol / diisocyanate, which is a urethane-reactive component. Further, the liquid composition for forming an adhesive for forming the adhesive film 560 includes the solvent and / or the photopolymerization initiator described in the first embodiment, and includes the organic nanoparticles 320 (see FIG. 4) according to the present invention . Alternatively, the adhesive film 560 may comprise a black pigment (e.g., titanium black).

At this time, the (meth) acrylate-based reactive component may be contained in a proportion of about 60 to 70 parts by weight in the liquid composition for forming an adhesive. When the content of the reactive (meth) acrylate-based reactive component satisfies the above-described range, the finally produced adhesive film 560 can secure a low modulus and harden through photo-curing to secure good shape characteristics of the adhesive can do. On the other hand, the prepolymer component as the urethane-based reactive component may be contained in the liquid composition for forming an adhesive according to the present embodiment at a ratio of 30 to 40 parts by weight.

Further, the liquid composition for forming an adhesive according to the present embodiment may include a black pigment for suppressing light extraction by adhesion between a display panel and a structure, for example, a backlight unit. The black pigment functions to prevent light leakage in a bonded display device to ensure a light shielding property and to prevent the (meth) acrylate reactive component from interfering with the light curing by UV or the like. In one exemplary embodiment, the black pigment may use titanium black (Ti black). The titanium black may be added in a proportion of about 3 to 5 parts by weight in the liquid composition for forming an adhesive.

The photopolymerization initiator may be contained in a proportion of 0.01 to 10.0 parts by weight in the liquid composition for forming an adhesive. If the content of the photopolymerization initiator is less than 0.01 part by weight, the curing reaction rate of the (meth) acrylate-based reactive component becomes too slow or the curing efficiency becomes poor due to failure to perform the initiating function. If the content of the photopolymerization initiator exceeds 10.0 parts by weight, yellowing may be caused due to the ring structure characteristic of the photopolymerization initiator not participating in the curing.

4) composed of the porous polyimide core 322 (see FIG. 4) and the non-porous polyimide shell 326 (see FIG. 4) according to the present embodiment is a liquid composition for forming an adhesive And may be doped. In an exemplary embodiment, the organic nanoparticles 320 (see FIG. 4) may be added in a ratio of 1 to 20 parts by weight. If the content of the organic nanoparticles is less than this range, it is difficult to expect improvement in heat resistance and improvement in the inner-UV characteristics. If the content of the organic nanoparticles is larger than this range, the organic nanoparticles aggregate in the curing process, .

If necessary, an amine-based catalyst and / or a tin-based (Tin-based) catalyst may be used so as to promote the urethane polymerization from the urethane prepolymer in the liquid composition for forming an adhesive according to this embodiment. For example, an amine-based catalyst such as diethanolamine may be added in an amount of 1 to 3 parts by weight in a liquid composition for forming an adhesive, 0.2 to 0.5 parts by weight of a tin catalyst such as dibutyltin dilaurate (DBTL) Can be added.

A liquid composition for forming an adhesive in which the (meth) acrylate-based reactive component, the urethane-based prepolymer, the titanium black, and the organic nanoparticles according to the present invention are mixed is coated on a suitable substrate, On the upper surface of the main frame 540. The coating method is not particularly limited.

Subsequently, the liquid composition for forming an adhesive according to the present embodiment is subjected to photo-curing. Thus, the (meth) acrylate-based reactive component is cured to form a (meth) acrylate-based resin to form the first binder. For example, the liquid composition for forming an adhesive coated on a substrate can be cured using a light source, for example, a light source that emits ultraviolet light such as an LED lamp. Photocuring can be carried out by irradiating UV with an intensity of approximately 1000 to 5000, preferably 2500 to 4000 mJ / cm < 2 >, and can be performed for several seconds.

After the adhesive is irradiated with ultraviolet rays, the display panel 600 is attached to the structure 530, and the thermosetting process is performed on the composition in which the (meth) acrylate resin is cured. A urethane-based resin can be obtained while a chain is formed between the urethane prepolymers by the heat curing process. After the (meth) acrylate-based resin formed by the primary photo-curing is formed, the urethane-based prepolymer uniformly arranged between the network structures formed by the (meth) acrylate-based resin forms a urethane- do. In one exemplary embodiment, the thermal curing process may be performed at a temperature of 80 to 150 캜, preferably 100 to 120 캜 for 20 to 30 minutes.

At this time, the isocyanate, which is a reactive component constituting the urethane-based prepolymer, can be cured by moisture hardening. The isocyanate, which is a prepolymer used for curing the urethane resin, reacts with moisture even when exposed to the air, resulting in moisture hardening. In other words, when a liquid composition for forming an adhesive existing in the form of an isocyanate prepolymer is stored before being applied in the form of the adhesive film 560, the isocyanate reacts with water in the atmosphere to cure.

Thus, before the soft type (meth) acrylate resin is formed through the photo-curing process, the isocyanate prepolymer is cured by moisture hardening or the like, so that the hard type urethane resin can be formed first. The urethane prepolymer can not be uniformly arranged between the (meth) acrylate based resins since the bulky urethane-based resin in which the chemical cross-linking degree of the urethane polymer is excessively high is formed first so that the modulus of the adhesive film increases, Can be lowered.

However, according to the present invention, the organic nanoparticles 300 (see FIG. 4) having a porous core are dispersed in the adhesive film 560. By adding the organic nanoparticles having a porous structure, it is possible to prevent the modulus of the entire adhesive film 560 from rising even if the urethane resin is first formed by moisture hardening.

As described above, according to the present invention, since the modulus of the adhesive film 560 does not increase significantly, the anti-shock characteristic of the adhesive film 560 is not deteriorated, and the stress due to external impact is not transmitted to the liquid crystal panel 600 Do not. In addition, organic nanoparticles 320 (see FIG. 4) are dispersed and doped according to the embodiment of the present invention between the liquid crystal panel 600 and the main frame 540 constituting the backlight unit 530, The adhesive film 560 having a low modulus can maintain its shape despite the difference in thermal expansion between the substrates 601 and 602 constituting the liquid crystal panel 600 and the main frame 540 It is possible to maintain a stable adhesive force between the liquid crystal panel 600 and the main frame 540 (see the right drawing in Fig. 10). Thus, even if the thickness W2 of the adhesive film 560 according to the present embodiment is smaller than the thickness W1 (see Fig. 3A) of the conventional adhesive layer 60 (see Fig. 3A) (W2 <W1) It is possible to realize an extremely narrow bezel having a borderless type.

As described above, according to the present embodiment, low-modulus can be realized by dispersing the organic nanoparticles 320 (see FIG. 4) having a porous structure in the adhesive film 560. Accordingly, as schematically shown in FIG. 10, a liquid crystal panel 600 is formed between the liquid crystal panel 600 and the structure 530, and a soft type (meth) acrylate based resin and a hard type urethane based resin and organic nanoparticles The liquid crystal panel 600 and the structure body 530 can be attached to each other by using the adhesive film 560. In addition, when left in a high temperature state, the low-modulus adhesive film 560 does not peel off the liquid crystal panel 600 and the structure 530, despite the difference in thermal expansion coefficient between the liquid crystal panel 600 and the structure body 530, A strong adhesion can be maintained between the structures 530.

In the case of using a hard type adhesive having a strong adhesive strength in the past, there has been a problem in that the adhesive can not sustain the stress due to the deformation caused by the thermal expansion coefficient of the panel (glass) and the backlight unit as a structure (see FIG. However, the adhesive film 560 according to the present embodiment has relatively low modulus because the organic nanoparticles 320 (see FIG. 4) having a porous structure are dispersed. Accordingly, it is possible to solve such a problem caused by applying the conventional hard type adhesive, to ensure reliability, and to cope with a stress change due to a difference in thermal expansion coefficient between the display panel and the structure.

In other words, when the adhesive film 560 of the present invention is applied between the display panel 600 and the structure 530 supporting the display panel 600, It is possible to maintain a stable adhesion force between the substrate 530 and the structure 530. [ Further, even if the thickness W2 of the adhesive film 560 according to the present embodiment is made smaller than the thickness W1 of the conventional soft type or hard type adhesive 60 (see Fig. 3A), sufficient adhesion can be ensured, It is possible to implement an extremely narrow bezel having a lease type. In addition, the adhesive film 560 in which the organic nanoparticles 320 (see Fig. 4) is dispersed in accordance with the present embodiment does not cause a yellowing that is discolored into yellow or the like due to the ultraviolet rays generated during the curing process or the irradiation of the external light, Excellent adhesion can be maintained.

On the other hand, the adhesive film according to the present embodiment can be applied to an organic light emitting diode display device in addition to the above-described liquid crystal display device. 11 schematically shows an organic light emitting diode display device to which an adhesive film according to the present embodiment is applied between an organic light emitting diode display panel and a back cover, which is a structure supporting the same, according to an exemplary embodiment of the present invention Sectional view.

11, the organic light emitting diode display 700 includes an organic light emitting display panel 800 including a first substrate 801 and a second substrate 802, a first substrate 801, And a first polarizing plate 812 and a second polarizing plate 814 attached to the second substrate 802, respectively. On the other hand, as a structure for receiving and supporting the organic light emitting display panel 800, a back cover 730 having a substantially flat plate shape is placed on the back surface of the first substrate 801. The adhesive film 760 according to the present embodiment is positioned between the upper surface of the peripheral portion of the back cover 730 and the lower surface of the peripheral portion of the first substrate 801 of the organic light emitting display panel 800. [ Although not shown in the drawings, the organic light emitting diode display 700 includes a cabinet (not shown) for guiding the edges of the organic light emitting display panel 800, And a cover window (not shown) positioned on the second substrate 802 side.

The back cover 730 may be formed in a plate shape covering the back surface of the organic light emitting display panel 800. In an exemplary embodiment, the back cover 730 may be made of aluminum, stainless steel, or the like. Alternatively, the back cover 730 may be composed of a triple structure of upper and lower first and second metal layers, and an inorganic layer between these metal layers. The metal layer serves to emit high-temperature heat generated in the OLED panel 800.

The organic light emitting display panel 800 constituting the organic light emitting diode display 700 according to the present embodiment will be described in more detail with reference to FIG. 12, in the organic light emitting display panel 800 according to the present embodiment, a non-display area NDR is defined around the display area DR and the display area DR, 801 and the second substrate 802 are spaced apart from each other by a predetermined distance.

The first substrate 801 and / or the second substrate 802 constituting the display panel 800 may be made of glass or flexible plastic. For example, the first substrate 801 and the second substrate 802 may be formed of a material selected from the group consisting of polyimide, polyethersulfone, polyetherimide (PEI), and / or polyethylene terephthalate (PET) ) Material.

(Not shown), a driving thin film transistor DTr, and an organic light emitting diode E are formed in respective pixel regions constituting a display region DR of a first substrate 801, which may be a glass or a plastic substrate, . At this time, for encapsulation with the first substrate 801, a second substrate 802 called an in-cap substrate is attached to the first substrate 801 in a direction opposite to the first substrate 801 through an adhesive agent or a filler sealant 890 .

A driving thin film transistor DTr and a light emitting diode E constituted by a plurality of electrodes, signal lines and layers are disposed on the first substrate 801, which will be described in detail. A semiconductor layer 866 is formed in each pixel region of the display region DR of the first substrate 801. [ For example, the semiconductor layer 866 may be made of an oxide semiconductor material. In this case, a light shielding pattern (not shown) and a buffer layer (not shown) may be formed under the semiconductor layer 866. The light shielding pattern prevents light from being incident on the semiconductor layer 866, Thereby preventing deterioration of the semiconductor device. Alternatively, the semiconductor layer 866 may be made of polycrystalline silicon. In this case, the central portion of the semiconductor layer 866 forms an active region 866a that forms a channel, and the source region 866a is formed by doping a high concentration impurity into both sides of the active region 866a. And drain regions 866b and 866c.

A gate insulating film 863 made of an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx) is formed on the semiconductor layer 866. A gate electrode 862 corresponding to the active region 866a of the semiconductor layer 866 and a gate wiring (not shown) extending in one direction are formed in each pixel region in the display region DR, Respectively.

In particular, a first passivation layer 864 is formed on the entire upper surface of the gate electrode 862 and the gate wiring (not shown). The first protective layer 864 may be made of an organic insulating material such as an inorganic insulating material such as silicon or acrylic photo oxide (SiO ₂₎ or silicon nitride (SiNx). The first passivation layer 864 and the gate insulating film 863 under the first passivation layer 864 expose the source and drain regions 866b and 866c located on both sides of the active region 866a constituting the center of the semiconductor layer 866, 1 and 2 semiconductor layer contact holes 868a and 868b.

Although not shown in the figure, on the first passivation layer 864 including the semiconductor layer contact holes 868a and 868b, a data line (not shown) which intersects with a gate wiring (not shown), defines a pixel region, And a power supply wiring (not shown) is formed therebetween. Alternatively, the power supply wiring (not shown) may be formed on the gate insulating film 863 on which the gate wiring (not shown) is formed so as to be spaced apart from the gate wiring (not shown).

The first and second semiconductor layer contact holes 868a and 868b are spaced apart from each other on the first protective layer 864 including the first and second semiconductor layer contact holes 868a and 868b in the display region DR. Source and drain electrodes 872 and 874 which are in contact with the exposed source and drain regions 866b and 866c are formed.

A semiconductor layer 866 including source and drain electrodes 872 and 877 and source and drain regions 866b and 866c in contact with the electrodes 872 and 874; 862 constitute a driving thin film transistor DTr. Although not shown in the figure, a data wiring is formed which intersects the gate wiring (not shown) to define the pixel region. The switching thin film transistor (not shown) has the same structure as the driving thin film transistor DTr and is connected to the driving thin film transistor DTr.

The driving thin film transistor DTr illustrated in FIG. 12 has a coplanar structure in which a gate electrode 862, a source electrode 872, and a drain electrode 874 are positioned above the semiconductor layer 866. Alternatively, the driving thin film transistor DTr may have an inverted staggered structure in which a gate electrode is located below the semiconductor layer and a source electrode and a drain electrode are located above the semiconductor layer. In this case, the semiconductor layer may be made of amorphous silicon.

A second passivation layer 876 is formed on the entire surface of the first substrate 801 including the driving thin film transistor DTr and the switching thin film transistor (not shown) in the display area DR. A drain contact hole 875 is formed in the second passivation layer 876. A first electrode 882 constituting the organic light emitting diode E is connected to a drain of the driving thin film transistor DTr through a drain contact hole 875. [ And can be in electrical contact with the electrode 874. The second passivation layer 876 may be made of an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiN x), but may be made of an organic insulating material such as photo- It is possible.

A first electrode 882, an organic light emitting layer 884, and a second electrode 886 constituting the organic light emitting diode E are sequentially formed in a region substantially displaying an image on the second passivation layer 876 . The first electrode 882 is connected to the drain electrode 874 of the driving thin film transistor DTr.

Illustratively, the first electrode 882 is an anode electrode that is made of a material having relatively high work function values such as indium-tin-oxide (ITO) or indium-zinc-oxide , IZO). Meanwhile, the second electrode 886 may be a cathode electrode, and may be made of aluminum (Al) or aluminum alloy (AlNd), which is a material having a relatively low work function value.

In the exemplary embodiment, the organic light emitting layer 884 stacked between the first electrode 882 and the second electrode 886 may be composed of a single layer made of a light emitting material. In an alternative embodiment, the organic light emitting layer 284 may be formed using a hole injection layer (HIL), a hole transporting layer (HTL), an emitting material layer (EML), an electron transporting layer , ETL) and an electron injection layer (EIL), thereby maximizing the luminous efficiency.

Accordingly, when a predetermined voltage is applied to the first electrode 882 and the second electrode 886 according to a selected color signal, holes injected from the first electrode 882 and electrons injected from the second electrode 886 And is transported to the organic light emitting layer 884 to form an exciton. When the exciton transitions from the excited state to the ground state, light is generated and emitted in the form of visible light. At this time, in the case of the bottom emission type, the emitted light passes through the transparent first electrode 882 and exits to the outside, so that the organic light emitting diode E realizes an arbitrary image. Alternatively, in the case of the top emission type, the emitted light passes through the second electrode 884 and is emitted to the outside to realize an image.

A first electrode 882 is formed for each pixel region, and a bank 888 is located between the first electrodes 882 formed for each pixel region. The bank 888 may be formed of an organic insulating film. For example, the bank 888 may be formed to overlap the rim of the first electrode 882 in the form of surrounding each pixel, and may have a lattice shape having a plurality of openings as a whole in the display region DR. That is, the banks 888 are formed as a matrix type of a lattice structure as a whole on the first substrate 801, and the first electrodes 882 are separated into pixel regions with the banks 888 as boundaries for the respective pixel regions .

Alternatively, a passivation layer 890 may be formed on the front surface of the organic light emitting diode E. Since the moisture penetration into the organic light emitting layer 884 can not be completely suppressed by the second electrode 886 alone, moisture penetration into the organic light emitting diode E, particularly, the organic light emitting layer 284 can be prevented by forming the passivation layer 890. [ Can be suppressed. The passivation layer in one exemplary embodiment 890 may be a single layer structure consisting of an inorganic insulating material such as silicon oxide (SiO ₂₎ or silicon nitride (SiNx). In another exemplary embodiment, the passivation layer 890 comprises a first inorganic layer to be laminated on top of the second electrode (886) by using an inorganic insulating material such as silicon oxide (SiO ₂₎ or silicon nitride (SiNx) ( And an organic layer (not shown) laminated on the first inorganic layer (not shown) by using a polymer material such as an olefin resin, an epoxy resin, a fluororesin, a polyethylene terephthalate (PET), or a polysiloxane and it may have a multi-layer structure, such as a silicon oxide (SiO ₂₎ or silicon nitride (SiNx) and the second inorganic layer (not shown) are stacked on top of the organic layer (not shown) by using an inorganic insulating material such.

11, the adhesive film 760 is formed of a soft type (meth) acrylate resin, a hard type urethane resin, and organic nanoparticles 320 having a porous structure 4), and a black pigment. The modulus of the adhesive film 760 does not rise due to the organic nanoparticles having the porous structure.

The modulus of the adhesive film 760 does not increase significantly, so that the anti-shock property of the adhesive film 760 does not deteriorate. In addition, an adhesive film 760 dispersed and doped with organic nanoparticles 320 (see FIG. 4) according to an embodiment of the present invention is interposed between the OLED display panel 800 and the back cover 730, It is possible to provide a stable state between the organic light emitting display panel 800 and the back cover 730 in spite of the difference in thermal diffusions between the substrates 801 and 802 constituting the organic light emitting display panel 800 and the back cover 730. [ The adhesive force can be maintained.

Thus, even if the thickness W2 of the adhesive film 760 according to the present embodiment is smaller than the thickness W1 (see Fig. 3A) of the conventional adhesive 60 (see Fig. 3A) (W2 <W1) It is possible to realize an extremely narrow bezel having a borderless type. In addition, the adhesive film 760 in which the organic nanoparticles 320 (see FIG. 4) is dispersed according to the present embodiment does not cause yellowing that is discolored into yellow or the like due to ultraviolet rays generated in a curing process or irradiation with external light, Lt; / RTI &gt;

Hereinafter, the present invention will be described in more detail with reference to exemplary embodiments. However, the present invention is by no means limited to the invention described in the following examples.

Synthesis Example 1: Production of organic nanoparticles of porous PI core and non-porous PI shell

1) Porous PI core synthesis

Transparent dianhydride, 4,4'- (hexafluoroisopropylidene) diphthalic acid dianhydride (6FDA) and 4,4'-oxydianiline (ODA), a transparent diamine, were added in a molar ratio of 1: (NMP) or N-dimethylacetamide (DMAc) solvent to synthesize polyamic acid (PAA) having a molecular weight of 10,000 to 100,000.

Polymethyl methacrylate (PMMA) or lithium chloride, which is a porogen inducing material, is dissolved or dispersed in an NMP or DMAc solvent, and then mixed with the polyamic acid solution prepared above. The mixed solution was precipitated in methyl alcohol or acetone to obtain polyamic acid nanoparticles having a plurality of pore structures. Polyimide nanoparticles having pores were synthesized by performing chemical imidization reaction using acetic anhydride as a catalyst. SEM photographs of the porous polyimide nanoparticles synthesized according to this synthesis example are shown in FIGS. 13A and 13B. It can be seen that polyimide nanoparticles having a porous structure having many pores are synthesized.

2) Non-porous PI shell coating on porous PI core

The porous polyimide nanoparticles synthesized above were dispersed in NMP or DMAc organic solvent, and then mixed with the remaining polyamic acid solution in 1) without being used for preparing the porous PI core. Methyl alcohol or acetone and quenched to obtain nanoparticles having a structure in which the polyamic acid compound surrounds the porous PI core. The polyamic acid nanoparticles of the core-shell structure were heated at 300 DEG C so that the polyamic acid constituting the shell of the non-porous structure was cured with polyimide.

14A to 14C are SEM photographs of nanoparticles composed of a porous polyimide core synthesized according to the present synthesis example and a non-porous polyimide shell. It can be seen that the shell of the non-porous polyimide completely surrounds the porous core.

Synthesis Example 2: Production of organic nanoparticles of porous PI core and non-porous PI shell

Transparency The procedure of Example 1 was repeated except that pyromellitic dianhydride (PMDA) was used as the dianhydride and p-phenylenediamine (PPD) was used as the transparent diamine to prepare the organic nanoparticles of the core-shell structure Respectively.

Synthesis Example 3: Production of organic nanoparticles of porous PI core and non-porous PI shell

Transparency The procedure of Example 1 was repeated except that biphenyl-tetracarboxylic dianhydride (BPDA) was used as the dianhydride and benzidine was used as the transparent diamine to prepare the organic nanoparticles of the core-shell structure.

Synthesis Example 4: Production of organic nanoparticles of porous PI core and non-porous PI shell

(ODPA) was used as the transparent dianhydride and 2,2'-bis (trifluoromethyl) -4,4'-biphenyldiamine (TFMB) was used as the transparent diamine , The procedure of Example 1 was repeated to prepare an organic nanoparticle having a core-shell structure.

Synthesis Example 5: Preparation of organic nanoparticles of porous PI core and non-porous PI shell

As the transparent dianhydride, benzophenone-3,3 ', 4,4'-tetracarboxylic dianhydride (BTDA) was used and 2,2-bis [4- (4-aminophenoxy) phenyl] BAPP) was used to prepare organic nanoparticles of core-shell structure.

Synthesis Example 7: Production of organic nanoparticles of porous PI core and non-porous PI shell

Transparency As a transparent dianhydride, 2,2-Bis [4- (4-aminophenoxy) phenyl] propane (BAPP) was used as the transparent dianhydride and 1,2,4,5-cyclobutanetetracarboxylic dianhydride The procedures of Example 1 were repeated except that the organic nanoparticles of core-shell structure were prepared.

Synthesis Example 8: Production of organic nanoparticles of porous PI core and non-porous PI shell

Transparency As the dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride (CHDA) was used and as transparent diamine 2,2'-bis (trifluoromethyl) -4,4'-biphenyldiamine TFMB) was used to prepare organic nanoparticles of core-shell structure.

Example 1: Analysis of components of organic nanoparticles

Analysis was carried out to confirm the chemical composition of the organic nanoparticles synthesized in Synthesis Example 1. 15A is a graph showing AFM-IR (atomic force microscope (AFM) based infrared (IR) spectroscopy) analysis results of the organic nanoparticles synthesized in Synthesis Example 1. FIG. The results of the Py-GC / MS analysis on the particles and the results of the analysis are shown in Fig. It has been confirmed that it has a structure derived from a -CF ₃ substituent, a benzene ring and an anhydride corresponding to the expected chemical structure.

FIG. 15C is a graph showing the results of ¹⁵ N NMR analysis of the organic nanoparticles synthesized in Synthesis Example 1. FIG. The nitrogen peak formed on the polyimide (PI) main chain constituting the organic nanoparticles was observed at -132 ppm, which was in agreement with the chemical structure. 15D is a graph showing the results of ¹⁹ F NMR analysis of the organic nanoparticles synthesized in Synthesis Example 1. FIG. The fluorine peak of CF ₃ substituted with polyimide (PI) constituting the organic nanoparticles was observed at around -61 ppm, and was in accordance with the chemical structure.

Example 2: Production of optical transparent adhesive in which organic nanoparticles are dispersed

An optical transparent adhesive in which the organic nanoparticles synthesized in Synthesis Example 1 were dispersed was prepared. , 15 parts by weight of a (meth) acrylate-based photoreactive oligomer butadiene acrylate, 15 parts by weight of a (meth) acrylate-based photoreactive monomer mixed with 10 parts by weight of isobornyl acrylate and 5 parts by weight of dipropylene glycol diacrylate, 10 parts by weight of a C ₅ pressure-sensitive adhesive, 4.5 parts by weight of a photopolymerization initiator compounded with 4.5 parts by weight of Irgacure 184 as a UV photopolymerization initiator and 0.5 parts by weight of Irgacure 819, 20 parts by weight of a plasticizer as a polyisoprene resin, 10 parts by weight of organic nanoparticles synthesized in Synthesis Example 1 To obtain an adhesive composition. This was coated on a plastic cover window to a thickness of 300 mu m and irradiated with ultraviolet light having a intensity of 4000 mJ / cm &lt; 2 &gt; to completely cure the adhesive to form an optical transparent complex (OCR w / PI Core-shell).

Comparative Example 1: Production of optical transparent adhesive without dispersing organic nanoparticles

The procedure of Example 2 was repeated except that the organic nanoparticles composed of the porous core and the non-porous shell synthesized in Synthesis Example 1 were not used to prepare an optical transparent adhesive consisting only of an acrylate-based optical transparent resin (OCR).

Comparative Example 2: Production of optical transparent adhesive in which porous organic nanoparticles were dispersed

The procedure of Example 2 was repeated except that a polyimide core having a porous structure was used in place of the organic nanoparticles composed of the porous core synthesized in Synthesis Example 1 and the organic nanoparticles composed of the non-porous shell, to thereby prepare a transparent polyimide core Acrylate based optical transparent adhesive (OCR w / Porous PI).

Example 3 Measurement of Heat Resistance of Optical Transparent Adhesive

TGA analysis was performed to confirm the heat resistance characteristics of the optical transparent adhesive prepared in Example 2 and the optical transparent adhesive prepared in Comparative Example 1 and Comparative Example 2 according to the high temperature environment. The measurement results are shown in Fig. (OCR) of Comparative Example 1 in which the organic nanoparticles were not used in the 120 ° C range. As a result, it was confirmed that the heat resistance was improved by 0.9% by weight.

Example 4: Measurement of modulus of optical transparent adhesive

The storage modulus of the optical transparent adhesive prepared in Example 2 and the optical transparent adhesive prepared in Comparative Example 1 and Comparative Example 2 according to the temperature change were measured. The measurement results are shown in Fig. It was confirmed that the adhesive (OCR w / PI Core-shell) of Example 1 in which the organic nanoparticles are dispersed has the least change in elastic modulus in a low temperature and high temperature environment and can contribute to maintaining the modulus of the optical transparent adhesive.

Example 5: Measurement of displacement amount and restoration amount of optical transparent adhesive

The optical transparent adhesive prepared in Example 2 and the optical transparent adhesive prepared in Comparative Example 1 and Comparative Example 2 were measured for displacement, restoration amount and restoration amount according to an increase in load. The universal load tester TEC-10 was used and the load range was 0 to 9N. The center position of the adhesive was repeated 8 times and the average value of 4-8 measurements was taken. The tip size was Φ8.

The displacement amount measurement result is shown in Fig. 18A, and the restoration amount measurement result is shown in Fig. 18B. Table 1 shows the displacement amount and the restoration amount measurement result according to this embodiment. The average displacement rate was highest in the optical transparent adhesive (OCR w / PI Core-shell) in which the organic nanoparticles of Example 2 were dispersed, and the lowest in the optical transparent adhesive (OCR) of Comparative Example 1 in which the nanoparticles were not dispersed . In addition, in the case of an adhesive (OCR w / Porous PI) using a porous PI core nanoparticle, a recovery delay occurred due to gap filling in which the binder component penetrates into the pores.

Example 6: Production of elastic adhesive in which organic nanoparticles are dispersed

An elastic adhesive in which the organic nanoparticles synthesized in Synthesis Example 1 were dispersed was prepared. 10 to 15 parts by weight of N-acryloyl morpholine (ACMO) capable of increasing the curing rate and modulus as reactive (meth) acrylate-based components, 25 to 30 parts by weight of isobornyl acrylate (iBOA) 10 to 15 parts by weight of 2-phenoxyethyl acrylate and 5 to 10 parts by weight of tetraethylene glycol diacrylate, which can enhance the flexibility, are used. 10 to 15 parts by weight of diphenylmethane diisocyanate (MDI) as a urethane-based prepolymer and 30 to 40 parts by weight of a urethane reactive component blended with 20 to 25 parts by weight of an ether type urethane prepolymer were used. 1 to 3 parts by weight of Phenyl-bis (2,4,6-trimethylbenzoyl-phospine oxide) which is a long wavelength initiator of 405 nm as a photopolymerization initiator and suppresses surface hardening and accelerates deep-root hardening, 1 to 3 parts by weight of a catalyst diethanolamine, 0.2 to 0.5 parts by weight of dibutyltin dilaurate (DBTL) and 3 to 5 parts by weight of organic nanoparticles synthesized in Synthesis Example 1 were mixed to prepare a liquid composition for forming an elastic resin. The resulting liquid composition was irradiated with UV of 4000 mJ / cm 2 intensity to cure the (meth) acrylate reactive component. Then, the thermosetting is performed at 100 to 150 for 20 minutes to cure the urethane-based reactive component to obtain an elastic resin (elastic Resin w / dispersed organic nanoparticles dispersed in an elastic resin composed of a (meth) acrylate resin and a urethane- PI core-shell).

Comparative Example 3: Production of elastic adhesive without dispersing organic nanoparticles

The procedure of Example 6 was repeated except that the organic nanoparticles composed of the porous core synthesized in Synthesis Example 1 and the non-porous shell were not used to produce an elastic adhesive made of only elastic resin (elastic Resin).

Comparative Example 4: Production of elastic adhesive in which porous organic nanoparticles were dispersed

The procedure of Example 6 was repeated except that a polyimide core having a porous structure was used in place of the organic nanoparticles composed of the porous core synthesized in Synthesis Example 1 and the organic nanoparticles composed of the non-porous shell, whereby the elasticity of the elastic polyimide core (Resin w / Porous PI).

Example 7 Measurement of Heat Resistance of Elastic Adhesive

TGA analysis was performed to confirm the heat resistance characteristics of the elastic adhesive prepared in Example 6 and the elastic adhesive prepared in Comparative Example 3 and Comparative Example 4 according to the high temperature environment. The measurement results are shown in Fig. As shown in FIG. 19, the heat resistance characteristics of the adhesive (elastic resin) not using the organic nanoparticles were the lowest, and the organic nanoparticles composed of the porous core and the non-porous shell were dispersed in the elastic resin It was confirmed that the heat-resisting property of the elastic adhesive (elastic Resin w / PI core-shell) was the most excellent.

Example 8: Measurement of tensile modulus of elastic adhesive

The tensile modulus of the elastic adhesive prepared in Example 6 and the tensile modulus of the elastic adhesive prepared in Comparative Example 3 were measured. The measurement results are shown in Fig. 20 and Table 2 below. The tensile modulus of the elastic adhesive (elastic Resin w / PI core-shell) of Example 6 in which the organic nanoparticles are dispersed in the elastic resin is relatively low as compared with the elastic adhesive of Comparative Example 3 composed of only elastic resin (elastic Resin) Able to know. According to this embodiment, it was confirmed that the modulus of the elastic adhesive can be kept low by dispersing the porous core and the non-porous shell in the elastic resin.

Example 9 Measurement of Adhesive Force of Elastic Adhesive

The adhesive strengths of the elastic adhesives prepared in Example 6 and the elastic adhesives prepared in Comparative Examples 3 and 4 were measured by measuring the shear strength according to the UV irradiation time (respectively, Q-sun Evaluation using a tester). The measurement results are shown in Fig. 21 and Table 3. As shown in Fig. 21 and Table 3, in the elastic adhesive (elastic Resin) containing no organic nanoparticles, the adhesive force was sharply decreased by UV irradiation. On the other hand, according to Example 6, the elastic adhesive (elastic Resin w / PI core-shell) in which the organic nanoparticles composed of the porous core and the non-porous shell are dispersed in the elastic resin retains the original adhesive force even after 200 hours of UV irradiation , And even when the curing time was 500 hours, the deterioration of the adhesive strength was not significantly deteriorated. Accordingly, it has been confirmed that when the organic nanoparticles composed of the porous core and the non-porous shell are dispersed in the elastic resin according to the present invention, the adhesive force is not lowered even by UV irradiation.

Example 10 Measurement of Transmittance Change of Elastic Adhesive

The adhesive strengths of the elastic adhesives prepared in Example 6 and the elastic adhesives prepared in Comparative Examples 3 and 4 were measured by measuring the shear strength according to the UV irradiation time (respectively, Q-sun Evaluation using a tester). The measurement results are shown in Fig. As shown in FIG. 22, it can be seen that the elasticity adhesive (elastic Resin) containing no organic nanoparticles has a yellowing due to a sudden change in transmittance according to UV irradiation, and an adhesive (w / Porous PI) The transmittance was greatly decreased. On the other hand, the elastic adhesive (w / PI core-shell) prepared according to Example 6 showed that the transmittance did not change even after 500 hours of UV irradiation, and yellowing due to UV irradiation hardly occurred.

Although the present invention has been described based on the exemplary embodiments and examples of the present invention, the present invention is not limited to the technical ideas described in the above embodiments and examples. Those skilled in the art will appreciate that various modifications and changes may be made without departing from the spirit and scope of the invention as defined by the appended claims. It will be apparent, however, that such modifications and variations are all within the scope of the present invention.

100, 100A, 100B, 500, 700: display device
200, 600, 800: Display panel
290: Touch panel 300, 560, 760: Adhesive film
310: binder 320: organic nanoparticles
322: porous core 324: porosity
326: shell 400: cover window
410: Substrate 420, 430: Hard coating layer
530: backlight unit (structure) 540: main frame
550: bottom frame 730: back cover (structure)
Tr: thin film transistor TrA: switching region
P: pixel area DR: display area
NDR: non-display area DTr: driving thin film transistor
E: organic light emitting diode W2: adhesive film width

Claims (16)

A porous polyimide (PI) core having pores formed therein; And
A polyimide shell enclosing the porous polyimide (PI)
/ RTI &gt;
The method according to claim 1,
Wherein the porous polyimide (PI) core and the polyimide (PI) shell are composed of a transparent polyimide.
The method according to claim 1,
Wherein the core and the polyimide constituting the shell are represented by the following formula (1).
Formula 1

(Wherein X in the formula (1) is selected from the group consisting of the following X1 to X8, and Y in the formula (1) is selected from the group consisting of the following Y1 to Y5)

bookbinder; And
And organic nanoparticles dispersed in the binder,
Wherein the organic nanoparticles include a porous polyimide core having pores formed therein and a polyimide shell surrounding the porous polyimide core.
5. The method of claim 4,
Wherein the binder is composed of a (meth) acrylate resin, a urethane resin, a rubber resin, a siloxane resin, a combination thereof, and a copolymer thereof.
5. The method of claim 4,
Wherein the porous polyimide (PI) core and the polyimide (PI) shell are composed of a transparent polyimide.
5. The method of claim 4,
Wherein the core and the polyimide constituting the shell are represented by the following formula (1).
Formula 1

(Wherein X in the formula (1) is selected from the group consisting of the following X1 to X8, and Y in the formula (1) is selected from the group consisting of the following Y1 to Y5)

;

5. The method of claim 4,
Wherein the organic nanoparticles are dispersed in the adhesive film at a ratio of 0.1 to 20 parts by weight.
Display panel;
A cover window disposed outside the display panel; And
And an adhesive film applied between the display panel and the cover window,
Wherein the adhesive film comprises a binder and organic nanoparticles dispersed in the binder, wherein the organic nanoparticles include a porous polyimide (PI) core having pores formed thereon, and a porous polyimide (PI) core surrounding the porous polyimide A display device comprising a polyimide (PI) shell.
Display panel;
A structure supporting the display panel; And
And an adhesive film positioned between the display panel and the structure,
Wherein the adhesive film comprises a binder and organic nanoparticles dispersed in the binder, wherein the organic nanoparticles include a porous polyimide (PI) core having pores formed thereon, and a porous polyimide (PI) core surrounding the porous polyimide A display device comprising a polyimide (PI) shell.
11. The method according to claim 9 or 10,
Wherein the binder is a (meth) acrylate resin, a urethane resin, a rubber resin, a siloxane resin, a combination thereof, and a copolymer thereof.
11. The method according to claim 9 or 10,
Wherein the porous polyimide (PI) core and the polyimide (PI) shell are made of transparent polyimide.
11. The method according to claim 9 or 10,
Wherein the core and the polyimide constituting the shell are represented by the following formula (1).
Formula 1

(Wherein X in the formula (1) is selected from the group consisting of the following X1 to X8, and Y in the formula (1) is selected from the group consisting of the following Y1 to Y5)

11. The method according to claim 9 or 10,
Wherein the organic nanoparticles are dispersed in the adhesive film in a ratio of 0.1 to 20 parts by weight.
11. The method of claim 10,
Wherein the display panel is a liquid crystal panel, and the structure is a backlight unit.
11. The method of claim 10,
Wherein the display panel comprises an organic light emitting diode and the structure is a back cover.

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