KR20220113885A - Adhesive film, manufacturing method of same and plastic organic light emitting display comprising same - Google Patents

Abstract

The present application relates to an adhesive film, a manufacturing method thereof, and a plastic organic light emitting display including the same. The adhesive film according to an exemplary embodiment of the present application includes a polymer having a melting temperature (Tm) of 30 ℃ or more and a (meth)acrylate-based resin in an adhesive sheet, so that the adhesive sheet including the polymer has a low initial adhesive strength with the adhered substrate.

Description

Adhesive film, manufacturing method thereof, and plastic organic light emitting display including same

The present application relates to an adhesive film, a manufacturing method thereof, and a plastic organic light emitting display including the same.

Recently, with the development of display-related technologies, display devices that can be deformed in the use stage, such as folding, rolling in a roll shape, or stretching like a rubber band, are being researched and developed. Since these displays can be deformed into various shapes, it is possible to satisfy both the demand for enlargement of the display in the use stage and the demand for miniaturization of the display for portability.

The deformable display device may not only be transformed into a preset shape, but may also be transformed into various shapes according to a user's request or a situation in which the display device is used. Accordingly, it is necessary to recognize the deformed shape of the display and control the display device in response to the recognized shape.

On the other hand, since the deformable display device has a problem in that each configuration of the display device is damaged according to the deformation, each configuration of the display device must satisfy folding reliability and stability.

In particular, recently, the demand for a foldable display is increasing, and the demand for a plastic organic light emitting display, which is a type of a deformable foldable display, is also increasing. Since the foldable display involves folding and unfolding, it is essential to attach a support that serves as a guideline for the operation to the lower part of the substrate of the foldable display. In the case of an existing backplate for a display, an adhesive is coated on the cross-section of the substrate, so a process of additionally forming an adhesive or adhesive is required in order to attach a support serving as a guideline to the lower part.

In the process of attaching (DIC (driver IC) bonding) the semiconductor chip used to drive the pixels constituting the display during the manufacturing process of the plastic organic light emitting display, the display panel itself is made of flexible PI in the existing COF (Chip On FPC) process. It is being changed to a COP (Chip On Plastic) process that uses (polyimide) and attaches a semiconductor chip to the extended part of the PI.

The COP process is performed under high temperature and specific pressure conditions, and in the case of conventional adhesive products, there is a problem in that a large amount of air bubbles are generated around the semiconductor chip (DIC chip) during the COP process.

In addition, bubbles or unexpected foreign substances generated in the process of bonding the pressure-sensitive adhesive sheet to the substrate may be introduced, which is not desirable from the viewpoint of aesthetics or adhesiveness, and may require re-adhesion of the pressure-sensitive adhesive sheet. However, in the case of an adhesive sheet having high adhesive strength, such a re-adhesive operation is difficult.

Then, the technique of reducing such a bubble is devised. For example, there has been devised a technique for forming an uneven surface shape on an adhesive surface of a pressure-sensitive adhesive by using an embossed liner. In this case, even if air bubbles are mixed between the pressure-sensitive adhesives when the pressure-sensitive adhesive is bonded to the substrate, air easily flows out through the surface grooves of the pressure-sensitive adhesive, so that the air bubbles are easily removed without re-adhesiveness. However, the pressure-sensitive adhesive described above requires a certain thickness to form the grooves. In addition, when this pressure-sensitive adhesive is lightly adhered to the base material, the adhesive area becomes small due to the presence of grooves, which makes it easier to perform operations such as rework and position refresh, but sufficient adhesive force cannot be obtained. There is a possibility.

In order to strengthen the rework characteristics, recently, adhesive sheets are being developed in which the adhesive strength is maintained low in the initial stage of the adhesive sheet, and the adhesive strength is increased after a specific process.

Therefore, in consideration of this situation, the adhesive force is maintained low at the initial stage of adhesion, and at the same time, in the display COP process, with the ability to express sufficient adhesion necessary for fixing the adherend thereafter, the pressure-sensitive adhesive bubble due to high temperature exposure It is necessary to develop an adhesive sheet capable of preventing the decrease in adhesive strength and forming stable adhesive strength.

Japanese Patent Laid-Open No. 2006-299283

An object of the present application is to provide an adhesive film, a manufacturing method thereof, and a plastic organic light emitting display including the same.

An exemplary embodiment of the present application is a base film; And an adhesive film comprising an adhesive sheet provided on one side of the base film, wherein the opposite side of the surface of the adhesive sheet in contact with the base film is bonded to stainless steel (SUS304 substrate), and the initial adhesive strength after standing at 23° C. for 2 hours This is 100 gf / inch or less, and the post-adhesive force after heat treatment at 50 ° C. for 20 minutes is 300 gf / inch or more, and the opposite side of the surface of the adhesive sheet in contact with the base film is bonded to stainless steel (SUS304 substrate), It provides an adhesive film having a high-temperature adhesive strength of 100 gf/inch or more measured at 150° C. after holding at 150° C. for 1 minute.

Another exemplary embodiment of the present application includes the steps of preparing a base film; and applying and curing a pressure-sensitive adhesive composition on one side of the base film to form an adhesive sheet, wherein the opposite side of the side of the pressure-sensitive adhesive sheet in contact with the base film is attached to stainless steel (SUS304 substrate) On the other hand, the initial adhesive force after bonding at 23 ° C. for 2 hours is 100 gf / inch or less, and then the late adhesion strength after heat treatment at 50 ° C. for 20 minutes is 300 gf / inch or more, the opposite side of the side in contact with the base film of the adhesive sheet After bonding the surface to stainless steel (SUS304 substrate), the high-temperature adhesive strength measured at 150° C. and 150° C. after holding for 1 minute is 100 gf/inch or more, and the pressure-sensitive adhesive composition is a (meth) acrylate-based resin; a polymer having a melting temperature (Tm) of 30° C. or higher; and a curing agent, wherein the polymer is a copolymer of monofunctional polysiloxane and one or more monomers, and the curing agent is included in an amount of 0.2 parts by weight or more and 1.0 parts by weight or less based on 100 parts by weight of the (meth)acrylate-based resin. A method for producing an adhesive film is provided.

Another exemplary embodiment of the present application is an adhesive film according to the present application; And to provide a plastic organic light emitting display including a plastic substrate provided on the pressure-sensitive adhesive sheet side of the pressure-sensitive adhesive film.

Finally, an exemplary embodiment of the present application includes a liquid crystal display provided on the opposite surface of the surface in contact with the pressure-sensitive adhesive film of the plastic substrate; and an organic light emitting layer on a surface opposite to the surface of the liquid crystal display in contact with the plastic substrate.

The pressure-sensitive adhesive film according to an exemplary embodiment of the present application includes a polymer and (meth)acrylate-based resin having a melting temperature (Tm) of 30° C. or higher on the pressure-sensitive adhesive sheet, and the pressure-sensitive adhesive sheet including the same is the initial adhesive strength with the adherend substrate It has low characteristics.

In particular, in the case of the pressure-sensitive adhesive sheet included in the pressure-sensitive adhesive film according to the exemplary embodiment of the present application, the initial adhesion to the adherend is low, and at the same time, the adhesion is increased after a specific process to express sufficient adhesion to fix the adherend. have

That is, in the adhesive film according to the present application, the adhesive strength of the adhesive sheet to the substrate to be adhered is initially maintained low, so that no dirt is left even if it is removed during misadhesion. characterized by being maintained.

In addition, the pressure-sensitive adhesive film according to an exemplary embodiment of the present application is prepared by appropriately adjusting a specific amount of a curing agent and a specific (meth)acrylate-based resin in the pressure-sensitive adhesive sheet, so that the opposite side of the side in contact with the base film of the pressure-sensitive adhesive sheet is made of stainless steel ( After bonding to SUS304 substrate), 150°C, after holding for 1 minute, the high-temperature adhesive force measured at 150°C has a value of 100 gf/inch or more, preventing a decrease in the adhesive strength of the adhesive due to high-temperature exposure during the COP process of the display have the features to do it.

In addition, since the adhesive film according to an exemplary embodiment of the present application does not decrease adhesive strength even after maintaining at 150° C. for 30 minutes, the adhesive strength of the adhesive sheet can be maintained high even when the process is repeated at high temperature for a long time.

1 is a view showing a schematic laminated structure of an adhesive film according to an exemplary embodiment of the present application.
2 is a diagram illustrating a laminated structure of an adhesive film including a release film according to an exemplary embodiment of the present application.
3 is a view showing the size of a bubble according to an exemplary embodiment of the present application.
4 is a diagram illustrating a side view of an organic light emitting display according to an exemplary embodiment of the present application.
5 is a diagram illustrating a side view of an organic light emitting display according to an exemplary embodiment of the present application.
6 is a diagram showing a DSC graph of a polymer showing a glass transition temperature behavior.
7 is a diagram showing a DSC graph of a polymer showing a melting temperature behavior.

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

In the present specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the present invention pertains can easily carry out the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein.

An exemplary embodiment of the present application is a base film; And an adhesive film comprising an adhesive sheet provided on one side of the base film, wherein the opposite side of the surface of the adhesive sheet in contact with the base film is bonded to stainless steel (SUS304 substrate), and the initial adhesive strength after standing at 23° C. for 2 hours This is 100 gf / inch or less, and the post-adhesive force after heat treatment at 50 ° C. for 20 minutes is 300 gf / inch or more, and the opposite side of the surface of the adhesive sheet in contact with the base film is bonded to stainless steel (SUS304 substrate), It provides an adhesive film having a high-temperature adhesive strength of 100 gf/inch or more measured at 150° C. after holding at 150° C. for 1 minute.

In the case of the adhesive film according to the present application, the initial adhesive force of the adhesive sheet has a range of 100 gf / inch or less, and the later adhesive force after heat treatment has a value of 300 gf / inch or more, and the adhesion to the adherend substrate is initially maintained low, It is characterized in that no filth remains even when removed during misadhesion, and the adhesive strength with the adherend substrate is maintained by increasing the adhesive strength through a specific process thereafter.

In addition, the pressure-sensitive adhesive film according to an exemplary embodiment of the present application is prepared by appropriately adjusting a specific amount of a curing agent and a specific (meth)acrylate-based resin in the pressure-sensitive adhesive sheet, so that the opposite side of the side in contact with the base film of the pressure-sensitive adhesive sheet is made of stainless steel ( After bonding to SUS304 substrate), high-temperature adhesive strength measured in a thermal cabinet at 150°C and 1 minute at 150°C after bonding in a thermal cabinet has a value of 100gf/inch or more, high temperature exposure during the COP process of the display It has a feature that can prevent a decrease in the adhesive strength of the pressure-sensitive adhesive.

The initial adhesive strength and the late adhesive strength were measured using a texture analyzer (Stable Micro Systems) at a 180° angle and a peeling rate of 300 mm/min, and the adhesive sheet according to the present invention was measured with a size of 1 inch. After cutting with a 2 kg rubber roller, it was reciprocated once and attached to a SUS304 substrate, and then each measurement was performed.

That is, the initial adhesive strength is after cutting the adhesive sheet according to the present invention to a size of 1 inch, and attaching it to the SUS304 substrate by reciprocating it once with a 2 kg rubber roller and leaving it at 23 ° C. for 2 hours, 180 ° angle and 300 mm / It peels at a peeling rate of minutes and means a value measured using a texture analyzer (Stable Micro Systems, Inc.).

After the adhesive sheet according to the present invention is cut to a size of 1 inch, the adhesive sheet is attached to the SUS304 substrate by reciprocating once with a 2 kg rubber roller and left at 23° C. for 2 hours, and then at 50° C. for 20 minutes. After heat treatment, peeling at a 180° angle and a peeling rate of 300 mm/min means a value measured using a texture analyzer (Stable Micro Systems).

The high-temperature adhesive strength means the adhesive strength measured in a thermal cabinet at 150°C after holding for 1 minute in a thermal cabinet, and has a different meaning from the adhesive strength measured by lowering the temperature after raising the temperature to 150°C is to have That is, the high temperature adhesive strength according to the present application means the adhesive strength measured in a heating cabinet at an ambient temperature of 150° C. after maintaining at 150° C. for 1 minute in a thermal cabinet.

According to an exemplary embodiment of the present application, high-temperature adhesive strength was measured using a texture analyzer (Stable Micro Systems) at a 180° angle and a peeling rate of 300 mm/min, and the adhesive sheet according to the present invention was measured by 1 inch After cutting to the size of (inch), it was attached to the SUS304 substrate by reciprocating once with a 2 kg rubber roller, and then maintained at 150°C for 1 minute in a heating cabinet, and then measured at 150°C.

In an exemplary embodiment of the present application, the initial adhesive force after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to the SUS304 substrate at 23° C. for 2 hours is 100 gf/inch or less, preferably 95 gf/inch It may be less than or equal to inch, more preferably less than or equal to 90 gf/inch.

In another exemplary embodiment, the initial adhesive force after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to the SUS304 substrate at 23° C. for 2 hours is 5 gf/inch or more, preferably 10 gf/inch or more , more preferably 15 gf / inch or more.

In another exemplary embodiment, after bonding the opposite side of the side in contact with the base film of the pressure-sensitive adhesive sheet to the SUS304 substrate at 23° C. for 2 hours, and after heat treatment at 50° C. for 20 minutes, the post-adhesive strength is 300 gf/inch or more , preferably 400 gf / inch or more, more preferably 500 gf / inch or more.

In another exemplary embodiment, the post-adhesive strength of the pressure-sensitive adhesive sheet after bonding the opposite side of the surface in contact with the base film to the SUS304 substrate at 23° C. for 2 hours and then heat treatment at 50° C. for 20 minutes is 5000 gf/inch or less , Preferably it may be 4000 gf / inch or less, more preferably 3000 gf / inch or less.

In an exemplary embodiment of the present application, the medium-term adhesive strength after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to the SUS304 substrate and leaving it at 23° C. for 24 hours is 120 gf/inch or less, preferably 115 gf/inch inch or less, more preferably 110 gf/inch or less.

In another exemplary embodiment, the medium-term adhesive strength after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to the SUS304 substrate at 23° C. for 24 hours is 10 gf/inch or more, preferably 15 gf/inch or more , more preferably 20 gf / inch or more.

The pressure-sensitive adhesive film according to the present application includes a polymer having a melting temperature of 30° C. or higher as described above in the pressure-sensitive adhesive sheet, so that the adhesive strength is maintained at a low level even after 2 hours left at room temperature (23° C.) / 24 hours left It is characterized in that the adhesive strength with the substrate to be adhered is maintained by increasing the adhesive strength through a specific process after that, and it is characterized in that it does not leave any dirt even if it is removed during erroneous attachment.

In an exemplary embodiment of the present application, after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to stainless steel (SUS304 substrate), the high temperature adhesive strength measured at 150°C after holding at 150°C for 1 minute is It may be 100 gf/inch or more, preferably 130 gf/inch or more, and more preferably 150 gf/inch or more.

In an exemplary embodiment of the present application, after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to stainless steel (SUS304 substrate), the high temperature adhesive strength measured at 150°C after holding at 150°C for 1 minute is 500 gf/inch or less, preferably 400 gf/inch or less, more preferably 300 gf/inch or less.

In an exemplary embodiment of the present application, after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to stainless steel (SUS304 substrate), the high temperature adhesive strength measured at 150°C after holding at 150°C for 1 minute is 100 gf/inch or more and 500 gf/inch or less, preferably 130 gf/inch or more and 400 gf/inch or less, and more preferably 150 gf/inch or more and 300 gf/inch or less.

As the high temperature adhesive strength according to the present application maintains the above range, it is possible to prevent a decrease in the adhesive strength of the adhesive due to high temperature exposure during the COP process of the display, thereby maintaining the adhesive strength with the PI substrate and suppressing the generation of bubbles. will have

That is, in the case of the adhesive film according to an exemplary embodiment of the present application, the adhesive strength is maintained at a constant low level even after 2 hours left at room temperature (23° C.) / 24 hours left at room temperature (23° C.) Thereafter, the adhesive strength with the adherend is maintained by increasing the adhesive strength through a specific process, and also, as the high temperature adhesive strength maintains the above range, it is possible to prevent the decrease in the adhesive strength of the adhesive due to high temperature exposure during the COP process of the display. Therefore, it will have the characteristics of suppressing the maintenance of adhesion with the PI substrate and the generation of bubbles in the future.

In an exemplary embodiment of the present application, the value of the late adhesive force / initial adhesive force provides a pressure-sensitive adhesive film having a value of 3 or more and 100 or less.

In an exemplary embodiment of the present application, the value of the late adhesive force/initial adhesive force may be 3 or more and 100 or less, and preferably 10 or more and 80 or less.

In an exemplary embodiment of the present application, a value of the intermediate adhesive force/initial adhesive force is provided with an adhesive film having a value of 0.8 or more and 1.2 or less.

In an exemplary embodiment of the present application, after bonding the opposite side of the surface in contact with the base film of the pressure-sensitive adhesive sheet to stainless steel (SUS304 substrate), the high temperature adhesive force measured at 150°C after holding at 150°C for 1 minute is A1, and after bonding the opposite side of the side in contact with the base film of the pressure-sensitive adhesive sheet to stainless steel (SUS304 substrate), the high-temperature adhesive force measured at 150°C after holding at 150°C for 30 minutes is A2, and the A1 and A2 provides an adhesive film that satisfies the following formula (1).

[Equation 1]

0.7 ≤ A2/A1 ≤ 1.1

In an exemplary embodiment of the present application, after bonding the opposite side of the side in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), high temperature adhesive strength A1 measured at 150° C. after holding at 150° C. for 1 minute is the same as the definition of the high-temperature adhesive force.

In an exemplary embodiment of the present application, after bonding the opposite side of the side in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), high temperature adhesive strength measured at 150° C. after holding at 150° C. for 30 minutes ( A2) may be greater than 80 gf/inch.

In another exemplary embodiment, after bonding the opposite surface of the surface in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), high temperature adhesive strength (A2) measured at 150°C after holding at 150°C for 30 minutes ) may be 80 gf / inch or more, preferably 90 gf / inch or more, and more preferably 100 gf / inch or more.

In another exemplary embodiment, after bonding the opposite surface of the surface in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), high temperature adhesive strength (A2) measured at 150°C after holding at 150°C for 30 minutes ) may be 400 gf/inch or less, preferably 300 gf/inch or less.

In an exemplary embodiment of the present application, that Equation 1 is close to 1 means that the adhesive force does not decrease and remains constant even after a certain period of time has elapsed under the condition of high temperature (150° C.), and Equation 1 is within the above range. By having , the adhesive force is maintained at a certain level or more even in a long-time high-temperature process, so that it has excellent adhesion to the PI substrate.

In an exemplary embodiment of the present application, a polyimide substrate laminated on the opposite surface of the surface in contact with the base film of the adhesive sheet, and an IC chip (width x mm, After attaching length y mm, height z mm, 5 mm ≤ x ≤ 100 mm, 0.1 mm ≤ y ≤ 10 mm, 0.01 mm ≤ z ≤ 1 mm,

After applying pressure to the IC chip in the thickness direction (ZD) of the adhesive sheet for 5 seconds at 210° C. and 50 mPa, the size of the bubbles measured by analyzing the image measured with an optical microscope (30 magnification) of the adhesive sheet (D1) is intended to provide an adhesive film that satisfies the following formula (2).

[Equation 2]

D1 ≤ 160μm

D1 is the size of the bubble,

Taking the direction in which the pressure was applied to the IC chip as the observation direction,

The longest distance of the bubble from the long side of the IC chip is d1,

The shortest distance of the bubble from the long side of the IC chip is d2,

D1 is d1-d2.

In the exemplary embodiment of the present application, Equation 2 may be D1 ≤ 160 μm, preferably D1 ≤ 155 μm, more preferably D1 ≤ 150 μm.

In another exemplary embodiment, Equation 2 may be 0 µm ≤ D1 ≤ 160 µm, preferably 0 µm ≤ D1 ≤ 155 µm, more preferably 0 µm ≤ D1 ≤ 150 µm.

Specifically, the size of the bubble according to the present application can be confirmed in FIG. 3 . 3 shows a side view and a top view of a structure in which a PI substrate 50 and an IC chip 60 are laminated on an adhesive film 40 according to an exemplary embodiment of the present application.

That is, in Equation 2, when the direction in which the pressure is applied to the IC chip is the observation direction, it means that the observation is viewed from the top view direction in FIG. 3, and the longest distance (d1) of the bubble from the long side of the IC chip. and the shortest distance d2 of the bubble from the long side of the IC chip is d2 when an imaginary extension line is drawn perpendicular to the long side of the IC chip, and the longest distance in contact with the bubble is d1 In this case, the size of the bubble may be expressed as d1-d2.

In the exemplary embodiment of the present application, when a plurality of bubbles are generated, the size of the bubble may be defined based on the bubble having the maximum value of d1 for each bubble.

In the exemplary embodiment of the present application, the longest distance of the bubble from the long side of the IC chip and the shortest distance of the bubble from the long side of the IC chip are defined based on a direction perpendicular to the long side of the IC chip.

That is, in the case of the pressure-sensitive adhesive film according to the present application, since a specific pressure-sensitive adhesive composition is included in the pressure-sensitive adhesive sheet, it has a characteristic capable of suppressing bubble generation even under high temperature conditions. In the case of the pressure-sensitive adhesive film according to the present application, high temperature and In the process of bonding the high-pressure IC chip, it has a feature capable of preventing the bubbles from spreading from the IC chip.

In an exemplary embodiment of the present application, the IC chip refers to a Display Driver IC (Integrated Circuit) chip, which is used to drive pixels constituting a display such as an organic light emitting diode (OLED) or a liquid crystal display (LCD). semiconductor chip.

In an exemplary embodiment of the present application, the IC chip may be represented by a width x mm, a length y mm, and a height z mm, 5 mm ≤ x ≤ 100 mm, 0.1 mm ≤ y ≤ 10 mm, 0.01 mm ≤ z A range of ≤ 1 mm may be satisfied.

In an exemplary embodiment of the present application, x may satisfy 5 mm ≤ x ≤ 100 mm, 10 mm ≤ x ≤ 90 mm, 20 mm ≤ x ≤ 50 mm, and x may be 30 mm.

In an exemplary embodiment of the present application, y may satisfy 0.1 mm ≤ y ≤ 10 mm, 0.5 mm ≤ y ≤ 5 mm, 0.5 mm ≤ y ≤ 3 mm, and y may be 1 mm.

In an exemplary embodiment of the present application, z may satisfy 0.01 mm ≤ z ≤ 1 mm, 0.05 mm ≤ z ≤ 0.9 mm, 0.1 mm ≤ z ≤ 0.5 mm, and z may be 0.2 mm.

In an exemplary embodiment of the present application, a polyimide substrate laminated on the opposite surface of the surface in contact with the base film of the adhesive sheet, and an IC chip (width x mm, After attaching length y mm, height z mm, 5 mm ≤ x ≤ 100 mm, 0.1 mm ≤ y ≤ 10 mm, 0.01 mm ≤ z ≤ 1 mm,

After applying pressure to the IC chip in the thickness direction (ZD) of the adhesive sheet at 210° C. and 50 mPa for 5 seconds, the bubble generation area measured by analyzing the image measured with an optical microscope (30 magnification) of the adhesive sheet The ratio (%) provides an adhesive film that satisfies the following formula (3).

[Equation 3]

0 % ≤ (V2/V1) x 100 % ≤30 %

In Equation 3,

Taking the direction in which the pressure was applied to the IC chip as the observation direction,

V1 is the area (mm ² ) on the pressure-sensitive adhesive sheet expressed as a value of (x mm + 2 mm) x (y mm + 2 mm), which means an area including the entire area of the IC chip,

V2 means the total area (mm ² ) of the bubbles in the pressure-sensitive adhesive sheet.

Equation 3 means the area ratio of the bubbles generated in the pressure-sensitive adhesive sheet, which means the area ratio of the generated air bubbles to the area of a specific pressure-sensitive adhesive sheet, and has a difference in meaning from representing the size of the bubbles generated as in Equation 2, but , In the end, in the case of the pressure-sensitive adhesive film according to an exemplary embodiment of the present application, the size of the generated bubbles is below a specific range (satisfying Equation 2), and the bubble generation area ratio of the generated bubbles satisfies below a specific range (satisfying Equation 3) Accordingly, it is possible to prevent a decrease in adhesive strength even under conditions of high temperature and high pressure, and thus has a feature that can suppress the occurrence of bubbles in the adhesive sheet.

In an exemplary embodiment of the present application, Equation 3 is 0% ≤ (V2/V1) x 100 % ≤ 30 %, preferably 0.5% ≤ (V2/V1) x 100 % ≤ 15 %, more preferably 1% ≤ (V2/V1) x 100 % ≤ 10 %.

In an exemplary embodiment of the present application, V1 refers to a specific area within the adhesive sheet, and the area on the adhesive sheet expressed as a value of (x mm + 2 mm) x (y mm + 2 mm) (mm ² ) , means an area including the entire area of the IC chip.

In an exemplary embodiment of the present application, the V1 is an area (mm ² ) on the pressure-sensitive adhesive sheet expressed as a value of (x mm + 2 mm) x (y mm + 2 mm), an area including the entire area of the IC chip Specifically, the V1 is the area (mm ² ) on the adhesive sheet expressed as a value of (x mm + 2 mm) x (y mm + 2 mm), and the center of V1 and the center of gravity of the IC chip are Means the area on the matching adhesive sheet.

In the exemplary embodiment of the present application, the V2 refers to the total area of the bubbles generated in the pressure-sensitive adhesive sheet, and the shape of the bubbles is not limited to a circle, an ellipse, a polygon, and the like.

In an exemplary embodiment of the present application, a polyimide substrate laminated on the opposite surface of the surface in contact with the base film of the adhesive sheet, and an IC chip (width x mm, After attaching length y mm, height z mm, 5 mm ≤ x ≤ 100 mm, 0.1 mm ≤ y ≤ 10 mm, 0.01 mm ≤ z ≤ 1 mm,

After applying pressure to the IC chip in the thickness direction (ZD) of the adhesive sheet at 210° C. and 50 mPa for 5 seconds, the bubble generation area measured by analyzing the image measured with an optical microscope (30 magnification) of the adhesive sheet The ratio (%) provides an adhesive film that satisfies the following formulas 4 and 5.

[Equation 4]

0 % ≤ (V2/M1) x 100 ≤30 %

[Equation 5]

5cm ² ≤ M1 ≤ 100 m ²

In the above formulas 4 and 5,

Taking the direction in which the pressure was applied to the IC chip as the observation direction,

M1 means the total area of the adhesive sheet,

V2 means the total area of the bubbles generated in the pressure-sensitive adhesive sheet.

In an exemplary embodiment of the present application, M1 means the total area of the adhesive sheet, and when the adhesive sheet has a rectangular parallelepiped shape, it means a value of a x b (a: horizontal length, b: vertical length), The shape of the adhesive sheet is not limited thereto.

In an exemplary embodiment of the present application, M1 refers to the total area of the adhesive sheet, and may satisfy the range of 5cm ² ≤ M1 ≤ 100 m ² , preferably 10cm ² ≤ M1 ≤ 1 m ² .

Laminating a PI (polyimide) substrate on the opposite side of the side in contact with the base film of the adhesive sheet, and an IC chip (width x mm) on the opposite side of the side in contact with the adhesive sheet of the PI (polyimide) substrate , length y mm, height z mm, 5 mm ≤ x ≤ 100 mm, 0.1 mm ≤ y ≤ 10 mm, 0.01 mm ≤ z ≤ 1 mm), attach the IC chip in the thickness direction of the adhesive sheet (ZD) As a condition of applying pressure for 5 seconds under conditions of 210°C and 50mPa, the condition of attaching the IC chip to the adhesive film of the present application using TAB bonding machine equipment in the actual COP process (pressure for 5 seconds under conditions of 210°C, 50mPa) ) and the bubble size and bubble generation area ratio are used as evaluation criteria to indicate that the pressure-sensitive adhesive sheet according to the present application includes a specific pressure-sensitive adhesive composition in the actual COP process to minimize the occurrence of bubbles.

1 shows a side view of the adhesive film according to the present application, and specifically, it can be confirmed that the adhesive film 40 has a form in which the base film 10 / the adhesive sheet 20 are sequentially stacked.

In an exemplary embodiment of the present application, the pressure-sensitive adhesive sheet includes a pressure-sensitive adhesive composition or a cured product thereof, and the pressure-sensitive adhesive composition includes a (meth)acrylate-based resin; a polymer having a melting temperature (Tm) of 30° C. or higher; and a curing agent, wherein the polymer is a copolymer of monofunctional polysiloxane and one or more monomers, and the curing agent is included in an amount of 0.2 parts by weight or more and 1.0 parts by weight or less based on 100 parts by weight of the (meth)acrylate-based resin. An adhesive film is provided.

The melting temperature according to the present application means a temperature at which a material undergoes a phase transition from a solid state to a liquid state. A change corresponding to , can be observed, and the temperature at this time can be defined as the melting temperature.

The melting temperature may be measured by differential thermal analysis (DSC). Specifically, it is a value measured by drawing the endothermic and calorific values of a material according to the temperature due to the phase change occurring when a sample of about 10 mg is sealed in a dedicated pen and heated to a constant temperature rising environment.

That is, the pressure-sensitive adhesive composition according to an exemplary embodiment of the present application includes a polymer showing a melting temperature (Tm) behavior, and thus has excellent variable properties, compared to a case including a polymer showing a glass transition temperature (Tg) behavior, , especially at room temperature (25° C.), the adhesive strength does not increase and has excellent stability over time.

6 shows a DSC graph for a polymer showing a glass transition temperature (Tg) behavior, and FIG. 7 shows a DSC graph for a polymer showing a melting temperature (Tm) behavior.

As can be seen from FIG. 6 , in the case of a polymer showing a glass transition temperature behavior, it can be confirmed that the phase transition occurs as the temperature is gradually increased with respect to the stable section (Glassy), and the phase transition is gradually increased in a wide temperature range (Glassy-> It can be confirmed that rubbery) occurs. That is, when a polymer exhibiting a glass transition temperature behavior is included, variable properties may occur, but the phase transition temperature range is wide, and some phase transition occurs when stored for a long time at room temperature (25° C.), and the adhesive strength of the pressure-sensitive adhesive layer increases and stability over time This may lead to poor results, and the variable properties may not be excellent as the phase transition state is a rubbery state.

Conversely, as can be seen in FIG. 7 , in the case of a polymer showing a melting temperature behavior, when the temperature is gradually increased with respect to the stable section (Solid), it can be seen that a sudden phase transition (Solid->liquid) occurs at a specific temperature (melting). have. That is, when a polymer showing a melting temperature behavior is included, a sudden phase transition occurs at a specific temperature value, and the phase transition does not occur at a temperature lower than the melting temperature, thereby suppressing an increase in adhesive strength (excellent stability over time) and higher than the melting temperature. At the above temperature, a phase transition occurs and the adhesive strength rapidly increases (excellent variable properties).

In an exemplary embodiment of the present application, the pressure-sensitive adhesive sheet may include the pressure-sensitive adhesive composition as it is.

In an exemplary embodiment of the present application, the pressure-sensitive adhesive sheet may include the pressure-sensitive adhesive composition dried.

In an exemplary embodiment of the present application, the pressure-sensitive adhesive sheet may include a cured product of the pressure-sensitive adhesive composition.

In an exemplary embodiment of the present application, the components of the polymer included in the pressure-sensitive adhesive composition may be confirmed through gas chromatography (GC) analysis, and the composition may be identified through nuclear magnetic resonance (NMR) analysis.

In an exemplary embodiment of the present application, the monomer provides an adhesive film represented by the following formula (1).

[Formula 1]

In Formula 1,

X is N or O;

R ₁ is hydrogen or a methyl group,

n is an integer from 1 to 30;

In the exemplary embodiment of the present application, n in Formula 1 may be an integer of 1 to 30.

In another exemplary embodiment, n in Formula 1 may be an integer of 10 to 25.

In another exemplary embodiment, n in Formula 1 may be an integer of 16 to 22.

In an exemplary embodiment of the present application, X may be N.

In an exemplary embodiment of the present application, X may be O.

In Formula 1, especially when the n value has the above range, some crystallization begins to occur due to entanglement between side chains of carbon, and accordingly, the polymer including the same begins to exhibit a melting temperature (Tm) behavior do.

The polymer having a melting temperature of 30° C. or higher means that when the monofunctional polysiloxane and at least one monomer represented by Formula 1 are copolymerized, the melting temperature of the final polymer has a value of 30° C. or higher.

In an exemplary embodiment of the present application, the melting temperature of the polymer may be 30 ℃ or more, 70 ℃ or less, preferably 60 ℃ or less, more preferably 50 ℃ or less.

The copolymer refers to a polymer obtained by polymerizing two or more types of different units, and in the copolymer, two or more types of units may be arranged irregularly or regularly.

The copolymer is a random copolymer having a form in which monomers are mixed without a regularity, a block copolymer in which blocks arranged by a certain section are repeated, or an alternating polymer having a form in which monomers are alternately repeated and polymerized There may be a copolymer (Alternating Copolymer), and the polymer having a melting temperature of 35° C. or higher according to an exemplary embodiment of the present application may be a random copolymer, a block copolymer, or an alternating copolymer.

In an exemplary embodiment of the present application, the monomer represented by Formula 1 provides an adhesive film that is at least one selected from the group consisting of STA (Stearyl acrylate) and STMA (Stearyl methacrylate).

As the monofunctional polysiloxane according to the present application, Chisso's FM-0721, Shin-Etsu's KF2012, etc. may be used, but is not limited thereto.

In an exemplary embodiment of the present application, the polymer having a melting temperature of 30° C. or higher may have a weight average molecular weight of 30,000 g/mol to 200,000 g/mol.

In another exemplary embodiment, the polymer having a melting temperature of 30° C. or higher may have a weight average molecular weight of 30,000 g/mol to 150,000 g/mol, preferably 30,000 g/mol to 100,000 g/mol. .

When the polymer having a melting temperature of 30° C. or higher according to the present application has a value of the weight average molecular weight in the above range, the arrangement of molecules in the polymer is excellent, and the initial adhesive force is low when the pressure-sensitive adhesive sheet is manufactured later.

The weight average molecular weight is one of the average molecular weights for which the molecular weight is not uniform and the molecular weight of a certain polymer material is used as a reference, and is a value obtained by averaging the molecular weight of the molecular species of the component molecular weight of the polymer compound having a molecular weight distribution by weight fraction.

The weight average molecular weight may be measured through Gel Permeation Chromatography (GPC) analysis.

In an exemplary embodiment of the present application, the polymer having a melting temperature of 30° C. or higher is the monofunctional polysiloxane; said one or more monomers; And it may be prepared by including a thermal polymerization initiator in a polymer composition comprising a solvent.

Toluene may be used as the solvent, but is not limited thereto, as long as it can dissolve the monofunctional polysiloxane and the one or more monomers, and a general organic solvent may be used accordingly.

In an exemplary embodiment of the present application, the polymer having a melting temperature of 30° C. or higher is based on 100 parts by weight of the polymer having a melting temperature of 30° C. or higher, 10 parts by weight or more and 40 parts by weight or less of the monofunctional polysiloxane, and 60 parts by weight of the monomer It provides an adhesive film comprising more than 90 parts by weight or less.

In an exemplary embodiment of the present application, the polymer having a melting temperature of 30° C. or higher is based on 100 parts by weight of the polymer having a melting temperature of 30° C. or higher, and 10 parts by weight or more and 40 parts by weight or less of the monofunctional polysiloxane, preferably 15 parts by weight. 30 parts by weight or more, more preferably 18 parts by weight or more and 25 parts by weight or less.

In an exemplary embodiment of the present application, the polymer having a melting temperature of 30° C. or higher is based on 100 parts by weight of the polymer having a melting temperature of 30° C. or higher, 60 parts by weight or more and 90 parts by weight or less, preferably 65 parts by weight or more, 85 parts by weight or more It may contain not more than 70 parts by weight or less, more preferably not less than 70 parts by weight and not more than 85 parts by weight.

When the polymer having a melting temperature of 30° C. or higher according to the present application includes the monofunctional polysiloxane and the monomer in parts by weight, the melting temperature value of the entire polymer may be appropriately formed, and accordingly, the pressure-sensitive adhesive sheet at room temperature The initial adhesive strength can be maintained low, and stability over time at room temperature is also excellent.

In an exemplary embodiment of the present application, the pressure-sensitive adhesive composition is based on 100 parts by weight of the (meth)acrylate-based resin, the melting temperature provides an adhesive film comprising 1 part by weight or more and 10 parts by weight or less of a polymer having a melting temperature of 30°C or more.

In another exemplary embodiment, the pressure-sensitive adhesive composition is based on 100 parts by weight of the (meth)acrylate-based resin, 1 part by weight or more and 7 parts by weight or less, preferably 3 parts by weight or more and 7 parts by weight of the polymer having a melting temperature of 30°C or more. may be included in sub-parts.

When the polymer having a melting temperature of 30° C. or higher is included in the pressure-sensitive adhesive composition in parts by weight within the above range, the amount of the polymer that can be present is suitable and excellent stability over time at room temperature, the adhesive force can be constantly maintained, When applied to a plastic organic light emitting display in the future, in a variable process, the variable performance is excellent.

As the pressure-sensitive adhesive composition according to an exemplary embodiment of the present application contains 0.2 parts by weight or more and 1.0 parts by weight or less of the curing agent based on 100 parts by weight of the (meth)acrylate-based resin, in the case of an adhesive sheet manufactured by curing it, The adhesive force at high temperature does not fall, and it has the characteristic which can suppress the generation|occurrence|production of a bubble.

That is, as the content of the curing agent is increased, the adhesive strength is decreased, and the high-temperature adhesive strength is also decreased. However, when the curing agent content is too low, the cohesive force is lowered and the high-temperature adhesive strength is rather lowered. As the pressure-sensitive adhesive composition according to the present application contains the curing agent in the above range, the high-temperature adhesive strength is maintained at a certain level, so that the adhesive strength at high temperature is not lowered. It also has a feature that can suppress the generation of air bubbles.

In an exemplary embodiment of the present application, the curing agent is 0.2 parts by weight or more and 1.0 parts by weight or less, preferably 0.3 parts by weight or more and 0.9 parts by weight or less, more preferably 0.3 parts by weight based on 100 parts by weight of the (meth)acrylate-based resin. It may be included in an amount of not less than 0.7 parts by weight or more.

In an exemplary embodiment of the present application, the curing agent may be an isocyanate-based curing agent, specifically, DR7030HD of Samyoung Ink.

In an exemplary embodiment of the present application, the (meth)acrylate-based resin may include a (meth)acrylate-based resin having a weight average molecular weight of 100,000 g/mol to 5 million g/mol.

In the present specification, (meth) acrylate is meant to include both acrylate and methacrylate. The (meth)acrylate-based resin may be, for example, a copolymer of a (meth)acrylic acid ester-based monomer and a crosslinkable functional group-containing monomer.

The copolymer means a polymer obtained by polymerizing two or more types of different units, and the copolymer may have two or more types of units arranged irregularly or regularly.

The copolymer is a random copolymer having a form in which monomers are mixed without a regularity, a block copolymer in which blocks arranged by a certain section are repeated, or an alternating polymer having a form in which monomers are alternately repeated and polymerized There may be an Alternating Copolymer.

The weight average molecular weight is one of the average molecular weights for which the molecular weight is not uniform and the molecular weight of a certain polymer material is used as a reference, and is a value obtained by averaging the molecular weight of the molecular species of the component molecular weight of the polymer compound having a molecular weight distribution by weight fraction.

The weight average molecular weight may be measured through Gel Permeation Chromatography (GPC) analysis.

In an exemplary embodiment of the present application, the (meth)acrylate-based resin provides an adhesive film having a glass transition temperature of less than 0°C.

The glass transition temperature of the (meth) acrylate-based resin means the glass transition temperature of the entire final (meth) acrylate-based resin in which the monomer is polymerized, and in the present specification, the glass transition temperature is a differential scanning calorimeter (DSC, Mettler Co., Ltd.), the endothermic and calorific values of the material due to the phase change are measured according to the temperature when the sample of about 10 mg is sealed in a dedicated pan and heated to a constant temperature environment.

Specifically, the glass transition temperature is a nominal value described in literature, catalogs, etc., or a value calculated based on the following general formula (1) (Fox formula).

[General formula (1)]

1/Tg=W1/Tg1+W2/Tg2+ … +Wn/Tgn

In the above general formula (1), Tg is the glass transition temperature of polymer A (unit: K), Tgi (i = 1, 2, ... n) is the glass transition temperature (unit: n) when the monomer i forms a homopolymer. : K) and Wi (i = 1, 2, ... n) represent the mass fraction of the monomer i in all the monomer components.

The general formula (1) is that polymer A is monomer 1, monomer 2, ... , means a calculation formula in the case of including n types of monomer components of the monomer n.

In another exemplary embodiment, the glass transition temperature of the (meth)acrylate-based resin is -110°C or more and less than 0°C, preferably -90°C or more and less than 0°C, more preferably -70°C or more and 0°C. may be less than

As the glass transition temperature of the (meth)acrylate-based resin satisfies the above range, the adhesive film according to the present application can maintain a certain level of adhesive strength even under high temperature and high pressure conditions, and can also minimize the occurrence of bubbles. will have characteristics.

That is, in the case of the adhesive film according to the present application, by controlling the glass transition temperature of the (meth)acrylate-based resin and adjusting the specific content of the curing agent, the adhesive strength at high temperature can satisfy a specific range.

The (meth) acrylic acid ester-based monomer is not particularly limited, but for example, an alkyl (meth) acrylate, and more specifically, as a monomer having an alkyl group having 1 to 12 carbon atoms, pentyl (meth) acrylate, n-butyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethyl One or two or more of hexyl (meth)acrylate, dodecyl (meth)acrylate, and decyl (meth)acrylate may be included.

The crosslinkable functional group-containing monomer is not particularly limited, but may include, for example, one or more than one of a hydroxyl group-containing monomer, a carboxyl group-containing monomer, and a nitrogen-containing monomer.

Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate ) acrylate, 8-hydroxyoctyl (meth)acrylate, 2-hydroxyethylene glycol (meth)acrylate, or 2-hydroxypropylene glycol (meth)acrylate.

Examples of the carboxyl group-containing monomer include (meth)acrylic acid, 2-(meth)acryloyloxyacetic acid, 3-(meth)acryloyloxypropyl acid, 4-(meth)acryloyloxybutyric acid, acrylic acid duplex, itaconic acid, maleic acid, or maleic anhydride; and the like.

Examples of the nitrogen-containing monomer include (meth)acrylonitrile, N-vinyl pyrrolidone or N-vinyl caprolactam.

At least one of vinyl acetate, styrene, and acrylonitrile may be further copolymerized with the (meth)acrylate-based resin from the viewpoint of improving other functionalities such as compatibility.

In an exemplary embodiment of the present application, the (meth) acrylate-based resin comprises at least one monomer selected from the group consisting of an alkyl (meth) acrylate monomer, a hydroxyalkyl acrylate monomer, and a nitrogen-containing monomer. An adhesive film is provided.

The alkyl acrylate and alkyl methacrylate are monomers having an alkyl group having 1 to 12 carbon atoms, pentyl (meth) acrylate, n-butyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylic rate, hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate and decyl (meth) acrylate It may include one or more than one of them.

Examples of the hydroxyalkyl acrylate include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 6-hydroxyhexyl acrylate, 8-hydroxyoctyl acrylate, 2 -Hydroxyethylene glycol acrylate, 2-hydroxypropylene glycol acrylate, etc. are mentioned.

Examples of the nitrogen-containing monomer include VP (N-vinyl pyrrolidone, N-vinyl pyrrolidone).

In an exemplary embodiment of the present application, the (meth)acrylate-based resin is based on 100 parts by weight of the (meth)acrylate-based resin, 70 to 99 parts by weight of an alkyl acrylate monomer, and 1 to 15 parts by weight of a hydroxyalkyl acrylate monomer and 0.5 to 10 parts by weight of the nitrogen-containing monomer.

Meaning that the (meth)acrylate-based resin contains 70 to 99 parts by weight of an alkyl acrylate monomer, 1 to 10 parts by weight of a hydroxyalkyl acrylate monomer, and 0.5 to 7 parts by weight of a nitrogen-containing monomer is an alkyl acrylate monomer; It means that the hydroxyalkyl acrylate monomer and the nitrogen-containing monomer are polymerized in the above weight ratio.

In an exemplary embodiment of the present application, the (meth)acrylate-based resin is based on 100 parts by weight of the (meth)acrylate-based resin, 70 to 99 parts by weight of an alkyl acrylate, preferably 80 to 99 parts by weight, more preferably It may contain 80 to 95 parts by weight.

In an exemplary embodiment of the present application, the (meth)acrylate-based resin is based on 100 parts by weight of the (meth)acrylate-based resin, 1 to 15 parts by weight of a hydroxyalkyl acrylate, preferably 5 to 13 parts by weight, More preferably, it may contain 7 to 10 parts by weight.

In an exemplary embodiment of the present application, the (meth)acrylate-based resin is 0.5 to 10 parts by weight, preferably 1 to 8 parts by weight, more preferably, based on 100 parts by weight of the (meth)acrylate-based resin, nitrogen-containing monomer It may contain 3 to 8 parts by weight.

In an exemplary embodiment of the present application, the (meth)acrylate-based resin is a first (meth)acrylate-based monomer having a glass transition temperature of 0°C or higher, a second (meth)acrylate-based monomer having a glass transition temperature of less than 0°C, and It provides an adhesive film comprising at least one monomer selected from the group consisting of a functional group-containing third (meth)acrylate-based monomer.

When the (meth)acrylate-based resin has the composition and content, as the high temperature adhesive strength of the adhesive sheet is maintained in a specific range later, the adhesive strength of the adhesive film is not reduced even in a high temperature COP process.

In an exemplary embodiment of the present application, the pressure-sensitive adhesive composition may further include at least one selected from the group consisting of a crosslinking agent, a solvent, a dispersing agent, a photoinitiator, a thermal initiator, and a tackifier.

According to an exemplary embodiment of the present specification, the crosslinking agent is hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate having 2 to 14 ethylene groups, trimethylolpropane Di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, 2-trisacryloyloxymethylethylphthalic acid, the number of propylene groups Acidic modifications of propylene glycol di(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate and dipentaerythritol a compound obtained by esterifying a polyhydric alcohol such as a mixture of hexa(meth)acrylate (trade name: TO-2348, TO-2349, manufactured by Dong-A Synthetic Co., Ltd., Japan) with α,β-unsaturated carboxylic acid; a compound obtained by adding (meth)acrylic acid to a compound containing a glycidyl group, such as a trimethylolpropane triglycidyl ether acrylic acid adduct and a bisphenol A diglycidyl ether acrylic acid adduct; Ester compound of a compound having a hydroxyl group or an ethylenically unsaturated bond, such as a phthalic acid diester of β-hydroxyethyl (meth)acrylate and a toluene diisocyanate adduct of β-hydroxyethyl (meth)acrylate, and a polyhydric carboxylic acid , or adducts with polyisocyanates; (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate; and 9,9'-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene, which may include one or more selected from the group consisting of, but not limited to, those known in the art. You can use common ones.

According to an exemplary embodiment of the present specification, the photoinitiator is a triazine-based compound, a biimidazole compound, an acetophenone-based compound, an O-acyloxime-based compound, a thioxanthone-based compound, a phosphine oxide-based compound, a coumarin-based compound, and a benzophenone It may be substituted with one or two or more substituents selected from the group consisting of non-based compounds.

Specifically, according to an exemplary embodiment of the present specification, the photoinitiator is 2,4-trichloromethyl-(4'-methoxyphenyl)-6-triazine, 2,4-trichloromethyl-(4'-methyl Toxystyryl)-6-triazine, 2,4-trichloromethyl-(piflonyl)-6-triazine, 2,4-trichloromethyl-(3',4'-dimethoxyphenyl)-6 -triazine, 3-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}propanoic acid, 2,4-trichloromethyl-(4'-ethyl ratio triazine-based compounds such as phenyl)-6-triazine or 2,4-trichloromethyl-(4'-methylbiphenyl)-6-triazine; 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl biimidazole or 2,2'-bis(2,3-dichlorophenyl)-4,4',5 biimidazole compounds such as ,5'-tetraphenylbiimidazole; 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxye Toxy)-phenyl (2-hydroxy)propyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenyl acetophenone, 2-methyl-(4-methylthiophenyl)-2-mol Acetopes such as polyno-1-propan-1-one (Irgacure-907) or 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one (Irgacure-369) non-type compounds; O-acyloxime compounds such as Ciba Geigy's Irgacure OXE 01 and Irgacure OXE 02; benzophenone compounds such as 4,4'-bis(dimethylamino)benzophenone or 4,4'-bis(diethylamino)benzophenone; thioxanthone-based compounds such as 2,4-diethyl thioxanthone, 2-chlorothioxanthone, isopropyl thioxanthone or diisopropyl thioxanthone; 2,4,6-trimethylbenzoyl diphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentyl phosphine oxide or bis(2,6-dichlorobenzoyl)propyl phosphine oxide Phosphine oxide type compounds, such as; 3,3'-carbonylvinyl-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 3-benzoyl-7-(diethylamino)coumarin; 3-benzoyl-7-methoxy-coumarin or 10,10'-carbonylbis[1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-Cl] Coumarin-based compounds such as -benzopyrano[6,7,8-ij]-quinolizin-11-one may be used alone or two or more may be mixed, but the present invention is not limited thereto.

In addition, the thermal initiator may use one known in the art.

Toluene may be used as the solvent, but is not limited thereto as long as it can dissolve a specific material, and a general organic solvent may be used accordingly.

In the exemplary embodiment of the present application, the base film is PET (polyethylene terephthalate), polyester, PC (polycarbonate), PI (polyimide), PEN (polyethylene naphthalate), PEEK (polyether ether ketone), PAR ( polyarylate), polycylicolefin (PCO), polynorbornene, polyethersulphone (PES), and cycloolefin polymer (COP).

In another exemplary embodiment, the base film may be polyethylene terephthalate (PET).

In an exemplary embodiment of the present application, the thickness of the base film is 25 μm or more and 300 μm or less, preferably 30 µm or more and 270 µm or less, and more preferably 40 µm or more and 250 µm or less.

In addition, it is preferable that the said base film is transparent. The meaning that the base film is transparent here means that the light transmittance of visible light (400-700 nm) is 80% or more.

When the base film has the above range, the laminated pressure-sensitive adhesive film has a property capable of being thinned.

In an exemplary embodiment of the present application, the thickness of the pressure-sensitive adhesive sheet is 3 μm or more and 100 μm may be below.

In another exemplary embodiment, the thickness of the pressure-sensitive adhesive sheet is 3 μm or more and 100 μm or less, preferably 5 µm or more and 80 µm or less, more preferably 10 µm or more and 50 µm may be below.

When the thickness of the pressure-sensitive adhesive sheet is within the above range, the rate of occurrence of air bubbles inside the pressure-sensitive adhesive sheet may be lowered under high temperature conditions, and the adhesive strength with the substrate to be adhered thereafter is also excellent.

In an exemplary embodiment of the present application, the thickness of the adhesive film is 110 μm or more and 700 μm It provides the following adhesive films.

In another exemplary embodiment, the thickness of the pressure-sensitive adhesive film is 120 μm or more and 600 μm or less, preferably 125 µm or more and 550 µm or less, more preferably 130 µm or more and 500 µm may be below.

Since the pressure-sensitive adhesive film has the above range, it has a suitable thickness when applied to a plastic organic light emitting display in the future, and also has a characteristic that adhesive strength is not reduced in a high temperature COP process.

In an exemplary embodiment of the present application, the pressure-sensitive adhesive sheet may be laminated in plurality.

In an exemplary embodiment of the present application, it provides an adhesive film that further comprises a release film on the opposite surface of the surface in contact with the base film of the adhesive sheet.

The release film may be a hydrophobic film, a layer for protecting a very thin pressure-sensitive adhesive sheet, refers to a transparent layer attached to one side of the pressure-sensitive adhesive sheet, and a film excellent in mechanical strength, thermal stability, moisture shielding property, isotropy, etc. can be used For example, acetate-based, polyester-based, polyethersulfone-based, polycarbonate-based, polyamide-based, polyimide-based, polyolefin-based, cycloolefin-based, polyurethane-based and acrylic resin films such as triacetylcellulose (TAC) can be used, but is not limited thereto if it is a commercially available silicone-treated release film.

2 is a diagram illustrating a laminated structure of an adhesive film including a release film according to an exemplary embodiment of the present application. Specifically, it can be seen that the adhesive film 40 has a structure in which the base film 10 / the adhesive sheet 20 / the release film 30 are sequentially stacked.

All of the release film may be removed when applied to a display.

An exemplary embodiment of the present application comprises the steps of preparing a base film; and applying and curing a pressure-sensitive adhesive composition on one side of the base film to form an adhesive sheet, wherein the opposite side of the side of the pressure-sensitive adhesive sheet in contact with the base film is attached to stainless steel (SUS304 substrate) On the other hand, the initial adhesive force after bonding at 23 ° C. for 2 hours is 100 gf / inch or less, and then the late adhesion strength after heat treatment at 50 ° C. for 20 minutes is 300 gf / inch or more, the opposite side of the side in contact with the base film of the adhesive sheet After bonding the surface to stainless steel (SUS304 substrate), the high-temperature adhesive strength measured at 150° C. and 150° C. after holding for 1 minute is 100 gf/inch or more, and the pressure-sensitive adhesive composition is a (meth) acrylate-based resin; a polymer having a melting temperature (Tm) of 30° C. or higher; and a curing agent, wherein the polymer is a copolymer of monofunctional polysiloxane and one or more monomers, and the curing agent is included in an amount of 0.2 parts by weight or more and 1.0 parts by weight or less based on 100 parts by weight of the (meth)acrylate-based resin. A method for producing an adhesive film is provided.

In the present application, the pressure-sensitive adhesive sheet may be prepared by applying the pressure-sensitive adhesive composition on a base film with a bar coater.

An exemplary embodiment of the present application, the adhesive film according to the present application; And to provide a plastic organic light emitting display including a plastic substrate provided on the pressure-sensitive adhesive sheet side of the pressure-sensitive adhesive film.

An exemplary embodiment of the present application, the adhesive film according to the present application; a plastic substrate provided on the adhesive sheet side of the adhesive film; and an IC chip provided on a surface opposite to the surface of the plastic substrate in contact with the pressure-sensitive adhesive film.

An exemplary embodiment of the present application, a thin film transistor (TFT, thin film transistor) provided on the opposite surface of the surface in contact with the adhesive film of the plastic substrate; and an organic light emitting layer on a surface opposite to a surface of the thin film transistor (TFT) in contact with the plastic substrate.

An exemplary embodiment of the present application includes a liquid crystal display provided on the opposite surface of the surface of the plastic substrate in contact with the pressure-sensitive adhesive film; and an organic light emitting layer on a surface opposite to the surface of the liquid crystal display in contact with the plastic substrate.

In FIG. 4 , a laminated structure of the plastic organic light emitting display according to an exemplary embodiment of the present application can be confirmed.

In the plastic organic light emitting display according to the exemplary embodiment of the present application, an anisotropic conductive film (ACF Anisotropic Conductive Film) may be further included on a surface of the IC chip in contact with the plastic substrate.

The anisotropic conductive film refers to a material for circuit connection in which conductive fine particles are uniformly dispersed in an adhesive on a film, and has electrical anisotropy in the thickness direction of the film and insulation in the plane direction through a thermocompression bonding process.

In FIG. 5 , a laminated structure of the plastic organic light emitting display according to an exemplary embodiment of the present application can be confirmed.

The organic light emitting layer may be selected from the group consisting of an organic photoelectric device, an organic transistor, an organic solar cell, an organic light emitting device, and a micro LED device.

Hereinafter, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein.

< production example >

< Example 1>

1) polymerization of the first polymer (( met ) Acrylates polymerization of resin)

70/15/5 of ethylhexyl acrylate (EHA, Ehylhexylacrylate)/methyl methacrylate (MMA, Methylmethacrylate)/N-vinylpyrrolidone (VP, N-Vinylpyrrolidone)/hydroxyethylacrylate (HEA, hydroxyethylacrylate) After being added to ethyl acetate (EA, Ethyl Acetate) in a weight ratio of /10, azobisisobutyronitrile (AIBN), a thermal polymerization initiator, was added to obtain a (meth)acrylate-based resin having a weight average molecular weight of 1 million g/mol. prepared.

2) Polymerization of the second polymer (polymerization of a polymer having a melting temperature of 30° C. or higher)

A second polymer having a weight average molecular weight of 60,000 g/mol was prepared by adding a material having the second polymer composition and weight ratio of Table 1 to toluene, and then adding AIBN (azobisisobutyronitrile) as a thermal polymerization initiator. did.

In Table 1 below, FM0721 is a monofunctional polysiloxane manufactured by Chisso, and FM0721 is a (meth)acrylate in which polysiloxane is present.

3) Preparation of adhesive film

After adding an isocyanate curing agent (DR7030HD by Samyoung Ink Co., Ltd.) in an amount of 0.3 parts by weight based on 100 parts by weight of the (meth)acrylate-based resin, it was diluted with a toluene solution so as to have a solid content of 20%.

The prepared adhesive composition was coated on a polyethylene terephthalate (PET) film (T91455) treated with MPI's double-sided anti-static (AS) to a thickness of 15 µm, and both sides were anti-static (Anti-static) , AS) treated polyethylene terephthalate (PET) (RF12AS) was applied, and then aged at 40° C. for 2 days to prepare an adhesive film.

< Example 2>

In Example 1, an adhesive film was prepared in the same manner as in Example 1, except that the curing agent was used in an amount of 0.7 parts by weight.

< comparative example 1>

In Example 1, an adhesive film was prepared by preparing in the same manner as in Example 1, except that the content of the curing agent was used in an amount of 1.5 parts by weight.

< comparative example 2>

In Example 1, an adhesive film was prepared in the same manner as in Example 1, except that 0.1 parts by weight of the curing agent was used.

Table 1 below shows the compositions and weight ratios of the first polymer, the second polymer, and the curing agent included in the adhesive films of Examples 1 and 2, Comparative Examples 1 and 2, and the curing agent.

first polymer
(weight ratio) second polymer hardener
(DR-7030HD) monomer
(weight ratio) parts by weight Example 1 EHA/MMA/VP/HEA
=70/15/5/10 EHA/MMA/VP/HEA
=70/15/5/10 5 0.3 Example 2 EHA/MMA/VP/HEA=70/15/5/10 FM0721/STMA/STA
=20/60/20 5 0.7 Comparative Example 1 EHA/MMA/VP/HEA=70/15/5/10 FM0721/STMA/STA
=20/60/20 5 1.5 Comparative Example 2 EHA/MMA/VP/HEA=70/15/5/10 FM0721/STMA/STA
=20/60/20 5 0.1

For the adhesive films of Examples 1, 2, Comparative Example 1 and Comparative Example 2, evaluation data for initial adhesion, intermediate adhesion, late adhesion, high temperature adhesion, and bubble evaluation are shown in Table 2 below.

initial adhesion
(gf/inch) Medium adhesion
(gf/inch) Late Adhesion
(gf/inch) high temperature adhesion
(gf/inch) bubble evaluation
(occurrence level) Example 1 84 88 1727 214 48 μm Example 2 65 69 1605 165 144 μm Comparative Example 1 52 55 1317 84 215 μm Comparative Example 2 105 112 1857 71 202 μm

1. Initial adhesive strength: One adhesive sheet of the adhesive films prepared in Examples 1, 2, and Comparative Examples 1 and 2 was reciprocally laminated on stainless steel (SUS304 substrate) with a 2 kg rubber roller once and reciprocated at 23° C. After leaving for 2 hours in the stainless steel (SUS304 substrate), the film was measured using a texture analyzer (Stable Micro Systems) at a 180° angle and a peeling rate of 300 mm/min.

2. Medium-term adhesive strength: One adhesive sheet of the films prepared in Examples 1, 2, Comparative Examples 1 and 2 was laminated on stainless steel (SUS304 substrate) by reciprocating one time with a 2 kg rubber roller, and at 23° C. After standing for 24 hours, the film from the stainless steel (SUS304 substrate) was measured using a texture analyzer (Stable Micro Systems) at a 180° angle and a peeling rate of 300 mm/min.

3. Late adhesive strength: One adhesive sheet of the films prepared in Examples 1, 2, Comparative Examples 1 and 2 was laminated on stainless steel (SUS304 substrate) by a 2 kg rubber roller, and laminated at 50 ° C. After leaving for 20 minutes, the film from the stainless steel (SUS304 substrate) was measured using a texture analyzer (Stable Micro Systems) at an angle of 180° and a peeling rate of 300 mm/min.

4. High-temperature adhesive strength: Measured using a texture analyzer (Stable Micro Systems) at a 180° angle and a peeling rate of 300 mm/min, and the adhesive sheet according to the present invention was cut to a size of 1 inch. After that, it was attached to the SUS304 substrate by reciprocating with a 2kg rubber roller once, and then maintained at 150°C for 1 minute in a heating cabinet, and then measured at 150°C.

5. Bubble evaluation: For the adhesive sheet on which the PI (polyimide) substrate is laminated, the IC chip (width 30mm x length 1mm x height 0.2) on the opposite side of the surface of the PI (polyimide) substrate in contact with the adhesive sheet mm), the size of the bubbles generated when the IC chip was pressed in the thickness direction (ZD) of the adhesive sheet at 210° C. and 50 mPa for 5 seconds was shown.

As can be seen from Table 1, in the case of the pressure-sensitive adhesive film according to the present application, it was confirmed that the adhesive strength at high temperature was maintained in a certain range as a specific pressure-sensitive adhesive composition was included in the pressure-sensitive adhesive sheet.

That is, in the case of the pressure-sensitive adhesive film according to the present application, it could be confirmed that it has a feature that can prevent a decrease in the adhesive strength of the pressure-sensitive adhesive sheet due to high temperature exposure during the COP process of the display, and it can be confirmed that the size of the generated air bubbles is also minimized. Accordingly, it was confirmed that the adhesive strength did not decrease even under high temperature conditions.

In the case of the pressure-sensitive adhesive films of Comparative Examples 1 and 2, it can be seen that the adhesive strength is lowered when a high temperature condition is applied, and accordingly, in the actual COP process, the size of the bubbles generated in the pressure-sensitive adhesive sheet increases and the adhesive strength decreases. was able to confirm

Specifically, in the case of Comparative Examples 1 and 2, the content of the curing agent included in the pressure-sensitive adhesive composition exceeds a specific range (Comparative Example 1) or is less than a specific range (Comparative Example 2), the high temperature and high pressure conditions It was confirmed that the adhesive strength decreased when adding .

In addition, as can be seen in Examples 1 and 2 of Table 1, the adhesive film according to an exemplary embodiment of the present application includes a polymer and (meth)acrylic having a melting temperature (Tm) of 30° C. or higher in the adhesive sheet. It was confirmed that, including the rate-based resin, the pressure-sensitive adhesive sheet including the same had a low initial adhesion to the substrate to be adhered.

In particular, in the case of the pressure-sensitive adhesive sheet included in the pressure-sensitive adhesive film according to an exemplary embodiment of the present application, the initial adhesive strength with the adherend substrate is low, and at the same time, the adhesion strength increases after a specific process, thereby exhibiting sufficient adhesive force to fix the adherend substrate. In the adhesive film according to the present application, the adhesive strength of the adhesive sheet to the adherend substrate is initially maintained low, so that no dirt is left even if it is removed during misadhesion. It was confirmed that this was maintained.

10: base film
20: adhesive sheet
25: PI board
30: release film
40: adhesive film
50: plastic substrate
55: anisotropic conductive film (ACF Anisotropic Conductive Film)
60: IC chip
80: thin film transistor (TFT, thin film transistor)
90: organic light emitting layer
d1: the longest distance of the bubble from the long side of the IC chip
d2: the shortest distance of the bubble from the long side of the IC chip

Claims (21)

base film; and
an adhesive sheet provided on one surface of the base film;
As an adhesive film comprising a,
After bonding the opposite side of the side in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), the initial adhesive strength after leaving it at 23°C for 2 hours is 100 gf/inch or less, and then after heat treatment at 50°C for 20 minutes The adhesive strength is 300 gf/inch or more,
After bonding the opposite side of the surface in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), the high-temperature adhesive strength measured at 150° C. and 150° C. after holding for 1 minute is 100 gf/inch or more. The method according to claim 1,
The pressure-sensitive adhesive film having a value of 3 or more and 100 or less of the late adhesive strength/initial adhesive strength. The method according to claim 1,
After bonding the opposite surface of the surface in contact with the base film of the pressure-sensitive adhesive sheet to stainless steel (SUS304 substrate), the medium-term adhesive strength after standing at 23° C. for 24 hours is 120 gf/inch or less. The method according to claim 1,
After bonding the opposite side of the surface in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), the high-temperature adhesive force measured at 150°C after holding at 150°C for 1 minute is A1,
After bonding the opposite side of the side in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), the high-temperature adhesive force measured at 150°C after holding at 150°C for 30 minutes is A2,
A1 and A2 are adhesive films that satisfy the following formula 1:
[Equation 1]
0.7 ≤ A2/A1 ≤ 1.1 5. The method according to claim 4,
After bonding the opposite side of the side in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), the high temperature adhesive strength (A2) measured at 150°C after holding at 150°C for 30 minutes is 80gf/inch or more adhesive film. The method according to claim 1,
A polyimide substrate laminated on the opposite side of the side in contact with the base film of the adhesive sheet, and an IC chip (width x mm, length y mm, height z mm, 5 mm ≤ x ≤ 100 mm, 0.1 mm ≤ y ≤ 10 mm, 0.01 mm ≤ z ≤ 1 mm),
After applying pressure to the IC chip in the thickness direction (ZD) of the adhesive sheet at 210° C. and 50 mPa for 5 seconds, the size of the bubbles measured by analyzing the image measured with an optical microscope (30 magnification) of the adhesive sheet (D1) is an adhesive film that satisfies the following formula 2:
[Equation 2]
D1 ≤ 160μm
D1 is the size of the bubble,
Taking the direction in which the pressure was applied to the IC chip as the observation direction,
The longest distance of the bubble from the long side of the IC chip is d1,
The shortest distance of the bubble from the long side of the IC chip is d2,
D1 is d1-d2. The method according to claim 1,
A polyimide substrate laminated on the opposite side of the side in contact with the base film of the adhesive sheet, and an IC chip (width x mm, length y mm, height z mm, 5 mm ≤ x ≤ 100 mm, 0.1 mm ≤ y ≤ 10 mm, 0.01 mm ≤ z ≤ 1 mm),
After applying pressure to the IC chip in the thickness direction (ZD) of the adhesive sheet at 210° C. and 50 mPa for 5 seconds, the area of bubble generation measured by analyzing the image measured with an optical microscope (30 magnification) of the adhesive sheet The ratio (%) is an adhesive film that satisfies the following formula 3:
[Equation 3]
0 % ≤ (V2/V1) x 100 ≤30 %
In Equation 3,
Taking the direction in which the pressure was applied to the IC chip as the observation direction,
V1 is the area (mm ² ) on the pressure-sensitive adhesive sheet expressed as a value of (x mm + 2 mm) x (y mm + 2 mm), which means an area including the entire area of the IC chip,
V2 means the total area (mm ² ) of the bubbles in the pressure-sensitive adhesive sheet. The method according to claim 1,
The pressure-sensitive adhesive sheet includes a pressure-sensitive adhesive composition or a cured product thereof,
The pressure-sensitive adhesive composition is a (meth) acrylate-based resin; a polymer having a melting temperature (Tm) of 30° C. or higher; and a curing agent;
The polymer is a copolymer of a monofunctional polysiloxane and at least one monomer,
The curing agent is an adhesive film that is included in an amount of 0.2 parts by weight or more and 1.0 parts by weight or less based on 100 parts by weight of the (meth)acrylate-based resin. 9. The method of claim 8,
The monomer is a pressure-sensitive adhesive film represented by the following formula (1):
[Formula 1]

In Formula 1,
X is N or O;
R ₁ is hydrogen or a methyl group,
n is an integer from 1 to 30; 10. The method of claim 9,
The monomer represented by Formula 1 is one or more selected from the group consisting of STA (Stearyl acrylate) and STMA (Stearyl methacrylate) adhesive film. 9. The method of claim 8,
The polymer having a melting temperature of 30° C. or higher is based on 100 parts by weight of a polymer having a melting temperature of 30° C. or higher,
10 parts by weight or more and 40 parts by weight or less of the monofunctional polysiloxane, and
An adhesive film comprising 60 parts by weight or more and 90 parts by weight or less of the monomer. 9. The method of claim 8,
The pressure-sensitive adhesive composition is based on 100 parts by weight of a (meth)acrylate-based resin,
The adhesive film comprising 1 part by weight or more and 10 parts by weight or less of the polymer having a melting temperature of 30°C or more. 9. The method of claim 8,
The (meth) acrylate-based resin is an adhesive film comprising at least one monomer selected from the group consisting of an alkyl (meth) acrylate monomer, a hydroxyalkyl acrylate monomer, and a nitrogen-containing monomer. The pressure-sensitive adhesive film according to claim 8, wherein the pressure-sensitive adhesive composition further comprises at least one selected from the group consisting of a crosslinking agent, a solvent, a dispersing agent, a photoinitiator, a thermal initiator, and a tackifier. The method according to claim 1, wherein the pressure-sensitive adhesive sheet has a thickness of 3 μm or more and 100 μm The adhesive film which is the following. The method according to claim 1, The thickness of the base film is more than 25㎛ 300㎛ The adhesive film which is the following. The method according to claim 1, wherein the base film is PET (polyethylene terephthalate), polyester (polyester), PC (polycarbonate), PI (polyimide), PEN (polyethylene naphthalate), PEEK (polyether ether ketone), PAR (polyarylate), PCO (polycylicolefin), polynorbornene (polynorbornene), PES (polyethersulphone) and COP (cycloolefin polymer) will be selected from the group consisting of an adhesive film. The adhesive film of claim 1, further comprising a release film on the opposite surface of the surface of the adhesive sheet in contact with the base film. preparing a base film; and
forming a pressure-sensitive adhesive sheet by applying and curing the pressure-sensitive adhesive composition on one surface of the base film;
A method for producing an adhesive film comprising:
After bonding the opposite side of the side in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), the initial adhesive strength after leaving it at 23°C for 2 hours is 100 gf/inch or less, and then after heat treatment at 50°C for 20 minutes The adhesive strength is 300 gf/inch or more,
After bonding the opposite side of the surface in contact with the base film of the adhesive sheet to stainless steel (SUS304 substrate), the high-temperature adhesive force measured at 150°C after holding at 150°C for 1 minute is 100 gf/inch or more,
The pressure-sensitive adhesive composition is a (meth) acrylate-based resin; a polymer having a melting temperature (Tm) of 30° C. or higher; and a curing agent;
The polymer is a copolymer of a monofunctional polysiloxane and one or more monomers,
The curing agent is a method for producing an adhesive film that is included in an amount of 0.2 parts by weight or more and 1.0 parts by weight or less based on 100 parts by weight of the (meth)acrylate-based resin. The adhesive film according to any one of claims 1 to 18; and
a plastic substrate provided on the adhesive sheet side of the adhesive film;
A plastic organic light emitting display comprising a. 21. The method of claim 20
a liquid crystal display provided on a surface opposite to the surface of the plastic substrate in contact with the pressure-sensitive adhesive film; and
an organic light emitting layer on a surface opposite to the surface of the liquid crystal display in contact with the plastic substrate;
A plastic organic light emitting display comprising a.

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