WO2021261900A1 - Thin film encapsulating composition - Google Patents

Abstract

The present invention relates to a solvent-free thin film encapsulating composition comprising a ladder-type polysilsesquioxane in which a photocurable functional group is grafted to a siloxane backbone, and a thin film encapsulating layer manufactured using same.

Description

Composition for thin film encapsulation

The present invention relates to a solvent-free thin film encapsulation composition exhibiting low dielectric properties and a thin film encapsulation layer prepared using the same.

With the development of the IT industry and intelligent information society, the display field has shown rapid growth. Recently, interest in a thin film encapsulation layer that protects the light emitting layer applied to an organic light emitting diode (OLED) or a quantum dot light emitting diode (QLED) from moisture, oxygen, etc. has been greatly focused.

In addition, in a flexible display manufactured by applying a flexible substrate, a thin film transistor layer, a display panel including a light emitting layer, a thin film encapsulation layer, a touch panel, and a cover glass are sequentially assembled, where the thin film encapsulation layer is formed of a very thin film. Therefore, since the touch panel and the display panel are sufficiently close to each other, electrical interference occurs between them. Such interference causes RC delay to occur, and there is a problem in that overall performance of the touch panel and the display is greatly reduced.

On the other hand, Patent Laid-Open No. 2014-0130016 discloses a method for forming a multilayer encapsulation thin film, but since the deposition occurs in a separate device, continuous transfer is required for the multilayer encapsulation thin film, and a lot of time is required for the deposition of the thin film. There is a downside to it.

[ Prior art literature ]

[ Patent Literature ]

(Patent Document 1) Patent Publication No. 2014-0130016

An object of the present invention is to limit electrical interference occurring in a display by imparting low dielectric properties to a thin film encapsulation layer using a solvent-free thin film encapsulation composition exhibiting low dielectric properties.

In order to solve the above problems, the present inventors have a solvent-free thin film encapsulation that exhibits low dielectric properties by reducing overall dielectric properties by mixing ladder-type polysilsesquioxane in which a photocurable functional group is connected to a siloxane main chain. The composition was invented.

The photocurable functional group may be a (meth)acrylic group.

The ladder-type polysilsesquioxane may be formed by condensation polymerization of a trimethoxysilane monomer (A) not including a photocurable functional group and a trimethoxysilane monomer (B) including a photocurable functional group.

The monomer (A) is trimethoxymethylsilane, trimethoxy (propyl) silane, trimethoxy (hexyl) silane, trimethoxy (octyl) silane, trimethoxy (decyl) silane, tri Methoxy (dodecyl) silane, (3-mercaptopropyl) trimethoxysilane, (3-chloropropyl) trimethoxysilane, vinyltrimethoxysilane, (3-aminopropyl) trimethoxy It may be at least one of silane and trimethoxyphenylsilane.

The monomer (A) may contain an aliphatic chain.

The monomer (B) may be at least one of 3-(trimethoxysilyl)propyl acrylate and 3-(trimethoxysilyl)propyl methacrylate.

The terminal group of the ladder-type polysilsesquioxane may be substituted with an alkyl key.

The monomer (A) and the monomer (B) may be condensation-polymerized in a molar ratio of 0:10 to 9:1.

The monomer (A) and the monomer (B) may be condensation-polymerized in a molar ratio of 0:10 to 4:6.

The solvent-free thin film encapsulation composition may further include a monomer (C) including a (meth) acryl group, and the (meth) acryl group of the monomer may be UV photopolymerized to the photocurable functional group.

The monomer (C) is 2-ethylhexyl acrylate, butyl acrylate, methyl methacrylate, methyl acrylate, ethyl acrylate, ethylene glycol phenyl ether acrylate, acrylic acid, 2-hydroxyethyl methacrylate and pentaeryth It may be one or more of ritol triacrylate.

The monomer (C) may be included in an amount of 10 wt% to 90 wt% with respect to the total composition.

The present invention also relates to a thin film encapsulation layer prepared by using the solvent-free thin film encapsulation composition.

The dielectric constant of the thin film encapsulation layer may be less than 3.5.

By using the solvent-free thin film encapsulation composition according to the present invention, it is possible to impart low dielectric properties to the thin film encapsulation layer, and by using the thin film encapsulation layer, it is possible to effectively block electrical interference occurring between the touch panel and the display panel. .

1 shows a synthesis example of ladder-type polysilsesquioxane.

2 shows the internal structure of a display including a thin film encapsulation layer prepared using a solvent-free thin film encapsulation composition.

3 shows the Fourier transform infrared spectroscopy (FT-IR spectroscopy) measurement results of Example 1. FIG.

4 shows the results of X-ray diffraction (XRD) analysis of Example 1.

5 shows a parallel plate capacitor of a metal-insulator-metal (MIM) structure.

6 shows a schematic diagram of a process of forming a thin film encapsulation layer using a solvent-free thin film encapsulation composition and a solvent-soluble thin film encapsulation composition.

7 shows the comparative evaluation results of the film morphology of the solvent-free thin film prepared using the solvent-free thin film encapsulation composition and the solvent-type thin film prepared using the solvent-free thin film encapsulation composition.

8 shows a measurement result of Fourier transform infrared spectroscopy (FT-IR spectroscopy) of Example 3. FIG.

9 shows the nuclear magnetic resonance (NMR) measurement results of Example 3. FIG.

10 shows the lifespan results of the organic light emitting diode devices to which Examples 1 and 3 were introduced, respectively.

The composition for encapsulating a solvent-free thin film according to the present invention may include a ladder-type polysilsesquioxane in which a photocurable functional group is connected to a siloxane main chain.

Here, "solvent-free" means that an organic solvent is not used when manufacturing a thin film encapsulation layer as a thin film encapsulation composition.

By not using the organic solvent as described above, it is possible to prevent an increase in the dielectric constant due to the residual micro-solvent after coating the composition, thereby further lowering the dielectric constant of the thin film.

While cracks occur in the solvent-type thin film prepared using the solvent-soluble thin film encapsulation composition, cracks do not occur in the solvent-free thin film prepared using the solvent-free thin film encapsulation composition. The crack deteriorates the thin film encapsulation property of the film by penetrating external oxygen and moisture.

6 shows a schematic diagram of a process of forming a thin film encapsulation layer using a solvent-free thin film encapsulation composition and a solvent-soluble thin film encapsulation composition. As can be seen from FIG. 6 , when the solvent-soluble thin film encapsulation composition is used, a thin film is formed on the ITO glass substrate using a blade coater and then the solvent is dried, for example, the solvent is dried at 80° C. for 1 minute. An additional process is required. That is, when the solvent-free thin film encapsulation composition is used, an additional drying process is not required, so that the thin film encapsulation layer can be efficiently and economically manufactured.

In one embodiment of the present invention, examples of the organic solvent include ethyl acetate, tetrahydrofuran, dichloromethane, and the like.

The solvent-free thin film encapsulation composition according to the present invention may exhibit low dielectric properties through a regular arrangement of the ladder-type polysilsesquioxane. In addition, the photocurable functional group of polysilsesquioxane has an advantage in additionally reacting with the acrylic monomer to form a low-k thin film, and at the same time, the thin film is flexible, and there is an advantage in having excellent thin film stability against thin film formation or external impact.

In one embodiment of the present invention, the photocurable functional group may preferably be a (meth)acrylic group. Here, the (meth) acryl group means a methacryl group or an acryl group. The use of a (meth)acrylic group as a photocurable functional group can easily introduce various additional linking structures into the ladder-type polysilsesquioxane basic structure.

In one embodiment of the invention, the ladder polysilsesquioxane may comprise aliphatic chains. The aliphatic chain may be, for example, a substituted or unsubstituted linear or branched aliphatic hydrocarbon chain having 6 to 20 carbon atoms, but is not limited thereto. For example, the linear aliphatic hydrocarbon chain may include an unsubstituted alkyl group having 6 to 20 carbon atoms, and the branched aliphatic hydrocarbon chain may include a trimethoxy (2-methylpentyl) silyl group, a trimethoxy (2-methyl It may include any one selected from the group consisting of a heptyl)silyl group, a trimethoxy(2-methylnonyl)silyl group, and a trimethoxy(2-methylundecyl)silyl group.

When the ladder-type polysilsesquioxane includes an aliphatic chain, the thin film may exhibit a lower dielectric constant value because the aliphatic chain portion is non-polar. In addition, since the aliphatic chain has high hydrophobicity, it can effectively block external moisture, thereby increasing the device lifespan. Accordingly, it is possible to obtain a thin film encapsulation effect of improved performance. The aliphatic chain may be derived from the aliphatic chain of the monomer (A) to be described later.

In the present invention, ladder-type polysilsesquioxane is formed by condensation polymerization of a trimethoxysilane monomer (A) not containing a photocurable functional group and a trimethoxysilane monomer (B) containing a photocurable functional group can be

In one embodiment of the present invention, the monomer (A) is trimethoxymethylsilane, trimethoxy(propyl)silane, trimethoxy(hexyl)silane, trimethoxy(octyl)silane, trime Toxy (decyl) silane, trimethoxy (dodecyl) silane, (3-mercaptopropyl) trimethoxysilane, (3-chloropropyl) trimethoxysilane, vinyltrimethoxysilane, ( 3-aminopropyl) may be at least one of trimethoxysilane and trimethoxyphenylsilane, but is not limited thereto.

In one embodiment of the present invention, the monomer (A) may comprise, but is not limited to, an aliphatic chain. The aliphatic chain may be, for example, a substituted or unsubstituted linear or branched aliphatic hydrocarbon chain having 6 to 20 carbon atoms, but is not limited thereto. For example, the linear aliphatic hydrocarbon chain may include an unsubstituted alkyl group having 6 to 20 carbon atoms, and the branched aliphatic hydrocarbon chain may include a trimethoxy (2-methylpentyl) silyl group, a trimethoxy (2-methyl It may include any one selected from the group consisting of a heptyl)silyl group, a trimethoxy(2-methylnonyl)silyl group, and a trimethoxy(2-methylundecyl)silyl group.

In one embodiment of the present invention, the monomer (B) may be at least one of 3-(trimethoxysilyl)propyl acrylate and 3-(trimethoxysilyl)propyl methacrylate, but is not limited thereto.

1 shows a synthesis example of ladder-type polysilsesquioxane. As shown in FIG. 1, trimethoxymethylsilane corresponding to the trimethoxysilane monomer (A) not containing a photocurable functional group and the trimethoxysilane monomer (B) containing a photocurable functional group is polymerized, A ladder-type polysilsesquioxane can be synthesized.

In one embodiment of the present invention, the monomer (A) and the monomer (B) may be condensation polymerized in a molar ratio of 0:10 to 9:1, preferably, a molar ratio of 0:10 to 4:6 can be condensation-polymerized. When the molar ratio of the monomer (A) and the monomer (B) satisfies the above range, the dielectric constant and the viscosity are lowered, so that there is an advantage in forming a low dielectric thin film.

In one embodiment of the present invention, the composition for encapsulating a solvent-free thin film according to the present invention may further include a monomer (C) comprising a (meth) acryl group, and the (meth) acryl group of the monomer is the photocurable group. The functional groups can be UV photopolymerized. When the monomer (C) containing a (meth) acryl group is further included, the thin film becomes flexible, and there is an advantage in thin film formation or stability of the thin film due to external impact.

In one embodiment of the present invention, the monomer (C) is 2-ethylhexyl acrylate, butyl acrylate, methyl methacrylate, methyl acrylate, ethyl acrylate, ethylene glycol phenyl ether acrylate, acrylic acid, 2-hydr It may be one or more of oxyethyl methacrylate and pentaerythritol triacrylate, but is not limited thereto.

In one embodiment of the present invention, the monomer (C) may be included in an amount of 10 wt% to 90 wt%, preferably 10 wt% to 50 wt%, based on the total composition. By setting the content of the monomer (C) within the above range, there is an advantage that a film having a low dielectric constant and high flexibility can be obtained.

In one embodiment of the present invention, the terminal group of the ladder polysilsesquioxane may be substituted with an alkyl group. Here, the alkyl group may be, for example, an alkyl group having 1 to 12 carbon atoms, but is not limited thereto. When the terminal group of the ladder-type polysilsesquioxane is substituted with an alkyl group, the non-polar and hydrophobic portions of the ladder-type polysilsesquioxane increase, so that the thin film exhibits a lower dielectric constant value, increases the device lifespan, and improves the performance of the thin film A sealing effect can be obtained.

The composition for encapsulating a solvent-free thin film containing ladder-type polysilsesquioxane of the present invention forms an internal network through UV curing, thereby forming a thin film with low dielectric properties that can be used as a thin film encapsulation layer.

In one embodiment of the present invention, in the display, a transistor layer, a display panel including a light emitting layer, a thin film encapsulation layer, a touch panel, and a cover glass may be sequentially disposed, and the thin film encapsulation layer of the present invention is formed as described in FIG. 2 . It may be positioned between the display panel and the touch panel in the display.

The dielectric constant is a unit that indicates the magnitude of the dielectric constant based on vacuum, and is a measure of how polarized the charge is when an external electric field is applied to the insulator. Therefore, the smaller the dielectric constant, the more effectively the thin film encapsulation layer can block the electrical interaction between the display panel and the touch panel.

The dielectric constant of the thin film encapsulation layer prepared by using the composition of the present invention may be less than 3.5. When the dielectric constant is less than 3.5, the thin film encapsulation layer can effectively block the electrical interaction between the display panel and the touch panel. The dielectric constant of the thin film encapsulation layer of the present invention may be preferably less than 2.5, more preferably less than 2.0.

The present invention is not limited by the following examples.

Example 1

Potassium carbonate (K ₂ CO ₃ ) 0.04 g of deionized water was added to a mixed solvent of 4.8 g of deionized water and 16 g of tetrahydrofuran (THF), followed by stirring at 550 rpm at room temperature for 30 minutes. To the mixed solution, a solution of 3.18 g of trimethoxyphenylsilane (PTMS) and 15.8 g of 3-(trimethoxysilyl)propyl methacrylate (molar ratio 2:8) was mixed at a rate of 2 g/min. The mixed solution was added dropwise and stirred at 550 rpm for 5 days at room temperature. After the stirring was completed, the solvent was evaporated to recover the synthesized material. Thereafter, in order to separate unsynthesized particles from the recovered material, it was redissolved in 100 ml of dichloromethane (DCM) and washed three times with deionized water using a separatory funnel. Excess magnesium sulfate (MgSO ₄ ) was added to the purified solution to remove residual deionized water, and then dried in a vacuum oven at 60° C. for 24 hours to prepare 2:8 ladder polysilsesquioxane (PSSQ).

[Formula 1]

< Check whether ladder-type polysilsesquioxane (PSSQ) is synthesized >

In order to confirm whether the 2:8 ladder-type PSSQ of Example 1 was synthesized, Fourier transform infrared spectroscopy (FT-IR spectroscopy) was measured.

3 shows a Fourier transform infrared spectroscopy (FT-IR spectroscopy) measurement result of Example 1. FIG. As can be seen in FIG. 3 , as a result of FT-IR measurement, a typical bimodal absorption peak that can confirm the ladder structure of PSSQ appeared at 1035 cm ^-1 to 1107 cm ^-1 , which is PSSQ vertical (-Si- OR-) and horizontal (-Si-O-Si-) directions can be seen from the stretching vibration of the siloxane bond. ^{In addition, C = O (1715 cm -1} ) peak, C = C (1636 cm ^-1 ) peak, and Si-Ph (1588 cm ^-1 ) peak corresponding to a phenyl group were observed corresponding to the acrylic group, which is a functional group of the ladder-type PSSQ.

< Confirmation of detailed structure of ladder-type polysilsesquioxane (PSSQ) >

To confirm the detailed structure of the 2:8 ladder PSSQ of Example 1, X-ray diffraction (XRD) analysis was performed.

4 shows the results of X-ray diffraction (XRD) analysis of Example 1. As can be seen in FIG. 4 , 6.2° (A) and 20.5° (B) shown in XRD mean the average intermolecular distance, the average thickness in the vertical direction of the main chain of the ladder-type PSSQ, and the distance values are each (d ₁ = 14.24 Å), (d ₂ = 4.33 Å).

< Checking the dielectric constant of the thin film >

On an indium tin oxide (ITO) glass substrate, the composition in which the 2:8 ladder PSSQ of Example 1 and IRGACURE 651 as a photoinitiator were uniformly mixed was formed into a thin film through a blade coater, and then exposed to UV-illuminator for 3J and cured to prepare a thin film.

The composition used to form the thin film was prepared by mixing 0.3 g of tetrahydrofuran (THF), 0.693 g of 2:8 ladder PSSQ, and 0.007 g of IRGACURE 651, stirred at room temperature at 600 rpm for 3 hours, and then the solvent was tetrahydrofuran. (THF) was dried in a vacuum oven at 60° C. for 24 hours. The tetrahydrofuran (THF) was added to prepare a high-viscosity 2:8 ladder-type PSSQ in the form of a thin film, and was removed by the drying process.

For measurement of the dielectric constant and dielectric constant of the thin film, Al (1 cm ² ) was deposited on the 2:8 ladder PSSQ thin film to form a parallel plate having a metal-insulator-metal (MIM) structure as shown in FIG. 5 . capacitors were manufactured. The thickness and capacitance of the thin film were measured, and the dielectric constant and dielectric constant were calculated using these values. The results are shown in Table 1 below.

[Table 1]

The 2:8 ladder-type PSSQ thin film exhibits a fairly low k dielectric constant.

Example 2

2:8 ladder-type PSSQ synthesized in Example 1 and IRGACURE 651 as a photoinitiator were added to the monomer pentaerythritol triacrylate (PETA) and then uniformly mixed, and the pentaerythritol triacrylate (PETA) content was It was adjusted as shown in Table 2 below.

Thereafter, in order to measure the dielectric constant and dielectric constant of the prepared composition for encapsulating the low dielectric thin film, a thin film was prepared as in Example 1 except that a photoinitiator was added in an amount of 0.7 wt % of the total composition.

To measure the dielectric constant and dielectric constant of the thin film of Example 2, a parallel plate capacitor was manufactured as in Example 1, the thickness and capacitance of the thin film were measured, and the dielectric constant and dielectric constant were calculated using these values.

In addition, the degree of flexibility of the thin film was evaluated through a film bending test in the following way.

Each prepared film was cut into a 120 mm long specimen, and the specimen was repeatedly bent according to ISO 8776/2-1988, and the number of repeated bending until the specimen was broken was measured.

◎: 100 times or more bending

○: The number of bending is 10 or more but less than 100 times

The results are shown in Table 2 below.

[Table 2]

2:8 In the case of the reference example not including the ladder-type PSSQ at all, the dielectric constant is very large compared to that of Example 1.

The smaller the PETA content, that is, the higher the content of 2:8 ladder PSSQ, the smaller the dielectric constant. becomes

Examples 2-1 and 2-2 in which the content of pentaerythritol triacrylate (PETA) was 90 wt% and 70 wt% had relatively large dielectric constants, but the thin films were very flexible.

In the case of Examples 2-3 to 2-5 in which the content of pentaerythritol triacrylate (PETA) is 50 to 90 wt%, it can be seen that the dielectric constant is kept low at less than 3.5 and the flexibility of the thin film is excellent.

Example 3

In the same manner as in Example 1, except that trimethoxyhexylsilane (HTMS) was used instead of trimethoxyphenylsilane (PTMS) to prepare a 2:8 ladder-type hexyl PSSQ containing an aliphatic chain, ladder-type PSSQ was prepared. The molar ratio of trimethoxyhexylsilane (HTMS) and 3-(trimethoxysilyl)propyl methacrylate used was 2:8.

To replace the terminal of 2:8 ladder-type hexyl PSSQ with a methyl group, 2 g of the prepared 2:8 ladder-type hexyl PSSQ powder was dissolved in anhydrous tetrahydrofuran solvent at 5 wt%, and then 0.04 mL of chlorotrimethylsilane and triethyl 0.04 mL of amine was added together and stirred at 40°C for 4 hours. After the stirring was completed, the solvent was evaporated to recover the synthesized material. Thereafter, in order to separate unsynthesized particles from the recovered material, it was redissolved in 100 ml of dichloromethane (DCM) and washed three times with deionized water using a separatory funnel. Excess magnesium sulfate (MgSO ₄ ) was added to the purified solution to remove residual deionized water, and then dried in a vacuum oven at 60° C. for 24 hours to prepare 2:8 ladder-type hexyl PSSQ in which the terminal group was substituted with a methyl group.

<Check whether ladder-type hexyl polysilsesquioxane (PSSQ) is synthesized>

In order to confirm whether the 2:8 ladder-type hexyl PSSQ of Example 3 was synthesized, Fourier transform infrared spectroscopy (FT-IR spectroscopy) was measured.

8 shows a measurement result of Fourier transform infrared spectroscopy (FT-IR spectroscopy) of Example 3. FIG. As can be seen in FIG. 8 , as a result of FT-IR measurement, a typical bimodal absorption peak that can confirm the ladder structure of PSSQ appeared at 1035 cm ^-1 to 1107 cm ^-1 , which is PSSQ vertical (-Si- OR-) and horizontal (-Si-O-Si-) directions can be seen from the stretching vibration of the siloxane bond. ^{In addition, a C=O (1716cm -1} ) peak, a C=C (1642cm ^-1 ) peak, and a CH (2949cm ^-1 ) peak corresponding to a hexyl group were observed corresponding to the acrylic group, which is a functional group of the ladder-type PSSQ.

< Check whether the terminal group of 2:8 ladder-type hexyl polysilsesquioxane (PSSQ) is substituted >

In order to confirm whether the terminal group of the 2:8 ladder-type hexyl PSSQ of Example 3 was substituted, nuclear magnetic resonance (NMR) analysis was performed.

9 shows the nuclear magnetic resonance (NMR) measurement results of Example 3. FIG. As can be seen in FIG. 9 , as a result of NMR measurement, a peak at 0.08 ppm for confirming Si-(CH ₃ ) ₃ substituted with a PSSQ terminal group was found at 0.08 ppm. It was confirmed that it was replaced with .

< Checking the dielectric constant of the thin film >

To measure the dielectric constant and dielectric constant of the thin film of Example 3, a parallel plate capacitor was manufactured in the same manner as in Example 1, the thickness and capacitance of the thin film were measured, and the dielectric constant and dielectric constant were calculated using these values. .

[Table 3]

Compared with Example 1, it was confirmed that Example 3 exhibited a lower dielectric constant k by introducing an aliphatic chain structure and replacing the terminal group with an alkyl group with a methyl group.

< Check the performance of the thin film encapsulation layer >

2:8 ladder-type hexyl PSSQ of Example 3, a composition in which IRGACURE 651 as a photoinitiator was uniformly mixed was coated on an organic light emitting diode device through a blade coater to form a thin film, and then exposed ^{to 4 J/cm 2 with a UV-illuminator} and curing the thin film to prepare a thin film encapsulation layer.

In order to measure the lifetime of the organic light emitting diode device due to the influence of the thin film encapsulation layer, the luminance of the organic light emitting diode device was measured over time using a transient EL measurement system.

10 shows the lifespan results of the organic light emitting diode devices to which Examples 1 and 3 were introduced, respectively. The time taken to decrease from the initial luminance (100%) to half (50%) is defined as the half-life, and as can be seen in FIG. 10 , in the case of Example 3, 14 times to 15 times as compared to Example 1 It was confirmed that the improved half-life of

Comparative Example 1

0.182 g of the 2:8 ladder PSSQ prepared in Example 1, 0.818 g of ethyl acetate as a solvent, and 0.07 g of IRGACURE 651 as a photoinitiator were mixed and stirred at room temperature at 600 rpm for 3 hours to prepare a solvent-soluble composition, and ITO glass After forming a thin film on the substrate using a blade coater, it was dried at 80° C. for 1 minute.

After that, in the same manner as in Example 1, it was cured by exposure to UV-illuminator 3J to prepare a thin film.

To measure the dielectric constant and dielectric constant of the thin film of Comparative Example 1, a parallel plate capacitor was manufactured as in Example 1, the thickness and capacitance of the thin film were measured, and the dielectric constant and dielectric constant were calculated using these values. The results are shown in Table 4 below.

[Table 4]

Compared to the solvent-free 2:8 ladder-type PSSQ thin film of Example 1 (solvent-free type), the solvent-soluble 2:8 ladder-type PSSQ thin film of Comparative Example 1 exhibits a higher dielectric constant value.

In the case of Comparative Example 1, it is thought that the dielectric constant is reduced due to the fine residual solvent, but film cracks are defective due to the natural evaporation of the fine residual solvent. lowers the

7 shows the comparative evaluation results of the film morphology of the solvent-free thin film prepared using the solvent-free thin film encapsulation composition and the solvent-type thin film prepared using the solvent-free thin film encapsulation composition.

As can be seen in FIG. 7 , cracks occurred in the solvent-type thin film prepared using the solvent-soluble thin film encapsulation composition, whereas cracks did not occur in the solvent-free thin film prepared using the solvent-free thin film encapsulation composition.

Claims (14)

A composition for encapsulating a solvent-free thin film, characterized in that the photocurable functional group comprises a ladder-type polysilsesquioxane connected to a siloxane main chain. The composition for encapsulating a solvent-free thin film according to claim 1, wherein the photocurable functional group is a (meth)acrylic group. According to claim 1, wherein the ladder-type polysilsesquioxane is a trimethoxysilane monomer (A) containing no photo-curable functional group and a trimethoxysilane monomer (B) containing a photo-curable functional group condensation polymerization A composition for encapsulating a solvent-free thin film, characterized in that formed by 4. The method according to claim 3, wherein the monomer (A) is trimethoxymethylsilane, trimethoxy(propyl)silane, trimethoxy(hexyl)silane, trimethoxy(octyl)silane, trimethoxy( Decyl) silane, trimethoxy (dodecyl) silane, (3-mercaptopropyl) trimethoxysilane, (3-chloropropyl) trimethoxysilane, vinyltrimethoxysilane, (3- Aminopropyl) trimethoxysilane and trimethoxyphenylsilane, characterized in that at least one, solvent-free thin film encapsulation composition. [Claim 5] The composition for encapsulating a solvent-free thin film according to claim 4, wherein the monomer (A) comprises an aliphatic chain. The solvent-free thin film encapsulation composition according to claim 3, wherein the monomer (B) is at least one of 3-(trimethoxysilyl)propyl acrylate and 3-(trimethoxysilyl)propyl methacrylate. . The composition for encapsulating a solvent-free thin film according to claim 3, wherein the terminal group of the ladder-type polysilsesquioxane is substituted with an alkyl group. The solvent-free thin film encapsulation composition according to claim 3, wherein the monomer (A) and the monomer (B) are condensation-polymerized in a molar ratio of 0:10 to 9:1. The solvent-free thin film encapsulation composition according to claim 8, wherein the monomer (A) and the monomer (B) are condensation-polymerized in a molar ratio of 0:10 to 4:6. The solvent-free thin film encapsulation according to claim 1, further comprising a monomer (C) comprising a (meth) acryl group, wherein the (meth) acryl group of the monomer (C) undergoes UV photopolymerization to the photocurable functional group. for composition. 11. The method according to claim 10, wherein the monomer (C) is 2-ethylhexyl acrylate, butyl acrylate, methyl methacrylate, methyl acrylate, ethyl acrylate, ethylene glycol phenyl ether acrylate, acrylic acid, 2-hydroxyethyl A composition for encapsulating a solvent-free thin film, characterized in that at least one of methacrylate and pentaerythritol triacrylate. The composition for encapsulating a solvent-free thin film according to claim 11, wherein the monomer (C) is included in an amount of 10 wt% to 90 wt% with respect to the total composition. A thin film encapsulation layer prepared by using the solvent-free thin film encapsulation composition of any one of claims 1 to 12. The thin film encapsulation layer according to claim 13, wherein the dielectric constant of the thin film encapsulation layer is less than 3.5.

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