Patent Description:
Organic light emitting diode (OLED) displays including thin film transistors (TFTs) are generally attracting attention as display devices for mobile device such as a digital camera, a video camera, a camcorder, a portable information terminal, and a smart phone.

Among the display devices for mobile device, flexible displays that are easy to carry and can be applied to display devices of various shapes, are recently under research and development as a next generation display device. Further, flexible displays based on an organic light emitting display technology have recently come into the spotlight.

When the flexible display is folded or wound, a stress is accumulated on a thin film layer and may cause peeling of the thin film layer. In order to prevent the peeling, a structure, in which an organic layer was formed after a reverse spacer was formed, was introduced. However, an encapsulation layer was not properly formed due to structural characteristics of the reverse spacer.

<CIT> discloses an organic EL display apparatus including: a substrate; plural organic EL devices formed over the substrate, each of the organic EL devices including a first electrode, an organic layer, and a second electrode which are provided in order from a side of the substrate, the organic layer including at least a light emitting layer; plural pixel isolation films, each of which is an insulating film and formed between the first electrodes located adjacent to each other; plural auxiliary wirings which are formed on the plural pixel isolation films and include a conductive material; and plural partition walls which are formed on the auxiliary wirings and include one of an insulator and a conductor which is reverse-tapered to have reverse-tapered portions, in which the plural auxiliary wirings and the second electrodes are electrically connected with each other in positions directly under the reverse-tapered portions of the plural partition walls.

<CIT> discloses an organic light emitting display device and a method for manufacturing the same. The organic light emitting display device includes a plurality of pixels, each including a set of sub pixels. Each of the sub pixels has an emissive area for emitting light and a transmissive area for passing the external light. At least two sub pixels are symmetrically arranged on each side of an auxiliary electrode, and share the auxiliary electrode.

<CIT> discloses an organic light emitting display device in which a partition wall is formed on a bank covering a portion of an auxiliary electrode, and thus, an aperture ratio is enhanced. The organic light emitting display device includes a first electrode, an auxiliary electrode, a first bank, and a partition wall. The first electrode may be connected to a driving transistor, and the auxiliary electrode may be disposed on the same layer as the first electrode. The first bank may cover a portion of the first electrode and a portion of the auxiliary electrode. A portion of a bottom surface of the partition wall may contact a top surface of the first bank, and the other portion except the portion of the bottom surface may be disposed on the auxiliary electrode.

<CIT> discloses that a pixel structure of an organic electroluminescent display panel has a plurality of sub-pixel regions. Each of the sub-pixel regions has a plurality of organic luminescent devices electrically connected in series, and the organic luminescent devices disposed in a same sub-pixel region are disposed between a source electrode of a thin film transistor and a voltage source.

<CIT> discloses that an organic light-emitting display device includes: a display substrate; an organic light-emitting device including a first electrode, an intermediate layer including an organic emission layer, and a second electrode; a pixel-defining layer; an anchor on the pixel-defining layer, the anchor having a cross-sectional width that narrows along a direction perpendicular to a surface of the display substrate; and a thin film encapsulation layer covering the organic light-emitting device and an outer surface of the anchor, the thin film encapsulation layer including an inorganic layer and an organic layer covering the inorganic layer.

<CIT> discloses a see-through organic light emitting display device including a light emitting region having a transparent anode, an organic light emitting layer, and a transparent cathode, and a see-through region having a transparent auxiliary electrode, which is configured to transmit external light. The transparent auxiliary electrode can be made from the same material as the transparent anode and separated from the transparent anode, and the transparent cathode extends into the see-through region so as to be electrically connected with the transparent auxiliary electrode.

<CIT> discloses that a CCM substrate includes as a light-emitting layer on a substrate a red conversion layer, a green conversion layer, and a light scattering layer; a bank which stands on the substrate, and partitions the light-emitting layer; and a light-transmission suppressing layer which is formed on at least a portion of a side surface of the bank which is a surface facing the light-emitting layer, and suppresses light transmission between the light-emitting layers (the red conversion layer, the green conversion layer, and the light scattering layer) with the bank interposed therebetween by causing the light to be reflected or scattered, in which the light-transmission suppressing layer is comprising metal or metal salt, and the bank has a group, an ion, or a molecule for immobilizing the metal or metal ion.

<CIT> discloses an organic light-emitting display device including a partition wall. The organic light-emitting display device includes a first bank insulating layer covering an edge of a lower electrode and a second bank insulating layer supporting the partition wall. The second bank insulating layer is completely spaced apart from the first bank insulating layer. The first bank insulating layer facing the second bank insulating layer is completely covered by an upper electrode which is disposed on a portion of the lower electrode exposed by the first bank insulating layer.

<CIT> is concerned with a luminescent display panel featuring a first protrusion and a second protrusion of a positive side slope on a bank, the first protrusion having a first body with a positive side slope and a second body with a negative side slope.

Accordingly, an object of the present disclosure is to address the above-described and other problems and provide a luminescent display panel having a structure capable of increasing an adhesive strength between thin film layers formed inside a display panel and improving an encapsulation capability of an encapsulation layer.

Various embodiments provide a luminescent display panel according to claim <NUM>.

The accompanying drawings, that may be included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain various principles of the disclosure.

Reference will now be made in detail to embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Detailed descriptions of known arts will be omitted if such may mislead embodiments of the disclosure. Names of the respective elements used in the following description are selected only for convenience of writing the specification and may be thus different from those used in actual products.

When a structure is described as being positioned "on or above", "under or below", "next to" another structure, this description should be construed as including a case in which the structures directly contact each other as well as a case in which a third structure is disposed therebetween. On the other hand, when a structure is referred to as being "directly on" another structure, there is no intervening structure present.

Shapes, sizes, ratios, angles, number, and the like illustrated in the drawings for describing embodiments of the disclosure are merely exemplary, and the present disclosure is not limited thereto unless specified as such.

In the following description, an organic light emitting diode (OLED) display panel is described as an example for an easy understanding of embodiments of the disclosure.

<FIG> is an equivalent circuit diagram of a pixel of an OLED display panel.

As shown in <FIG>, a pixel of an OLED display panel includes a switching thin film transistor T1 connected to a gate line GL and a data line DL, a driving thin film transistor T2 connected to the switching thin film transistor T1, a power line PL, and an organic electroluminescent cell, a storage capacitor C connected between the power line PL and a drain electrode of the switching thin film transistor T1, and an organic light emitting element OLED connected to the driving thin film transistor T2.

A gate electrode of the switching thin film transistor T1 is connected to the gate line GL, a source electrode of the switching thin film transistor T1 is connected to the data line DL, and the drain electrode of the switching thin film transistor T1 is connected to a gate electrode of the driving thin film transistor T2 and the storage capacitor C. A source electrode of the driving thin film transistor T2 is connected to the power line PL, and a drain electrode of the driving thin film transistor T2 is connected to the organic light emitting element OLED. The storage capacitor C is connected between the power line PL and the gate electrode of the driving thin film transistor T2.

When a scan pulse is supplied to the gate line GL, the switching thin film transistor T1 is turned on and supplies a data signal supplied to the data line DL to the storage capacitor C and the gate electrode of the driving thin film transistor T2. The driving thin film transistor T2 controls a current I, that is supplied to the organic light emitting element OLED from the power line PL, in response to the data signal supplied to the gate electrode of the driving thin film transistor T2, thereby adjusting an emission intensity of the organic light emitting element OLED. Even when the switching thin film transistor T1 is turned off, the driving thin film transistor T2 supplies the current I to the organic light emitting element OLED by a voltage charged to the storage capacitor C until the supply of the data signal is performed in a next frame. Hence, the driving thin film transistor T2 maintains the emission of the organic light emitting element OLED.

<FIG> is a cross-sectional view illustrating a structure of the OLED display panel according to an inventive embodiment, <FIG> is a cross-sectional view illustrating a structure of the OLED display panel according to the embodiment which does not fall under the claimed invention.

As shown in <FIG>, the driving thin film transistor T2 is formed on a substrate <NUM> and a buffer layer <NUM>. The driving thin film transistor T2 includes a semiconductor layer <NUM> having a source region 109a and a drain region 109b on both sides of the semiconductor layer <NUM>, a gate insulating layer <NUM> covering the semiconductor layer <NUM>, and a gate electrode <NUM> disposed on the gate insulating layer <NUM> at a location corresponding to the semiconductor layer <NUM>. The driving thin film transistor T2 further includes a first protective layer <NUM>, that covers the substrate <NUM> including the gate electrode <NUM> and includes contact holes <NUM> exposing the source region 109a and the drain region 109b positioned at ends of the semiconductor layer <NUM>, and a source electrode <NUM> and a drain electrode <NUM> respectively connected to the source region 109a and the drain region 109b through the contact holes <NUM>.

The OLED display panel includes a first electrode <NUM> positioned on the first protective layer <NUM> and a second protective layer <NUM> covering the driving thin film transistor T2, a bank insulating layer <NUM> (in other words, a bank <NUM>) having an organic hole <NUM> (e.g., a hole through which an organic light emitting element, or one or more layers of the organic light emitting element, passes or pass) exposing the first electrode <NUM>, a first protrusion <NUM> and a second protrusion <NUM> positioned on the bank insulating layer <NUM>, an organic layer <NUM> including a light emitting layer on the first electrode <NUM> exposed through the organic hole <NUM>, and a second electrode <NUM> positioned on the organic layer <NUM>.

The first protective layer <NUM> includes a contact hole <NUM> exposing the drain electrode <NUM> of the driving thin film transistor T2. The first electrode <NUM> is connected to the drain electrode <NUM> of the driving thin film transistor T2 through the contact hole <NUM>.

The substrate <NUM> may be made of glass or polymer that has flexible characteristics. Thus, the OLED display panel according to the embodiment of the disclosure is implemented as a flexible display panel or a foldable display panel.

The organic layer <NUM> may be divided into an electron injection layer EIL, an electron transport layer ETL, an emission layer EML, a hole transport layer HTL, and a hole injection layer HIL. The emission layer emits light of a specific wavelength while excitons produced by combining electrons from a cathode and holes from an anode return to a ground level.

When the first electrode <NUM> is a cathode, the second electrode <NUM> may be an anode. On the contrary, when the first electrode <NUM> is an anode, the second electrode <NUM> may be a cathode.

The first protrusion <NUM> has a shape in which a center portion of a vertical cross section is depressed. Further, the first protrusion <NUM> may have a shape extended along one direction of the pixel or an island shape disposed between the pixels. The first protrusion <NUM> may include polyimide or novalac resin.

An encapsulation layer <NUM> is positioned on the second electrode <NUM>. The encapsulation layer <NUM> has a structure in which at least one inorganic thin film layer <NUM> and <NUM> and at least one organic thin film layer <NUM> are alternately laminated. The encapsulation layer <NUM> entirely covers the organic layer <NUM>, in order to block the organic layer <NUM>, which is vulnerable to moisture, from the outside.

The organic layer <NUM> is not formed in at least a portion of the side of the first protrusion <NUM>. hus, the organic layer <NUM> on the bank insulating layer <NUM> is physically separated from the organic layer <NUM> on the first protrusion <NUM>. Namely, continuity of the organic layer <NUM> on the substrate <NUM> is broken around the first protrusion <NUM>.

<FIG> enlargedly illustrates the periphery <NUM> of the first protrusion <NUM> in the OLED display panel shown in <FIG> omitting the second electrode <NUM> for an easy understanding.

The first protrusion <NUM> and the second protrusion <NUM> are disposed on the bank insulating layer <NUM>. In particular, the first protrusion <NUM> is disposed in an organic layer broken portion in which there is no organic layer <NUM>. For example, the first protrusion <NUM> shown in <FIG> is disposed in the organic layer broken portion on the bank insulating layer <NUM>. The first protrusion <NUM> and the second protrusion <NUM> do not need to be disposed adjacent to each other. <FIG> schematically illustrates an exemplary structure of the first and second protrusions <NUM> and <NUM> for an easy understanding. For example, only one of the first and second protrusions <NUM> and <NUM> may be disposed between subpixels. It is preferable, but not required, that a height of the first protrusion <NUM> is less than a height of the second protrusion <NUM>. Namely, a distance between an upper surface of the second protrusion <NUM> and the substrate <NUM> may be designed to be greater than a distance between an upper surface of the first protrusion <NUM> and the substrate <NUM>.

The first protrusion <NUM> includes a first body <NUM> and a second body <NUM> on the first body <NUM>. As shown in <FIG>, the first body <NUM> has a positive side slope, and the second body <NUM> has a negative side slope. The first body <NUM> may be formed of polyimide, and the second body <NUM> may be formed of novalac resin.

More specifically, <FIG> illustrates that the side of the first body <NUM> and the side of the second body <NUM> each have one slope, by way of example. However, as shown in <FIG>, the side of the first body <NUM> and the side of the second body <NUM> may be curved and may have various slopes. In embodiments disclosed herein, the slope may indicate a maximum slope or an average slope of a side to be measured.

An upper surface of the first body <NUM> may protrude in a convex shape. The second body <NUM> may have a shape covering the protruding upper surface of the first body <NUM>. Further, the second body <NUM> may be disposed on the first body <NUM> in a shape covering a portion of the side of the first body <NUM>.

Referring to <FIG>, the second protrusion <NUM> is disposed on the bank insulating layer <NUM>. The second protrusion <NUM> has a positive side slope and may be formed of the same material as the first body <NUM>.

The organic layer <NUM> covers a side and an upper part of the bank insulating layer <NUM> exposed around the first electrode <NUM> and the organic hole <NUM>. In this instance, the organic layer <NUM> is not formed in an overlap area of the first protrusion <NUM> and the bank insulating layer <NUM>. The organic layer <NUM> is disposed to cover the upper surface of the first protrusion <NUM> and the upper surface of the second protrusion <NUM>. The organic layer <NUM> may be formed in at least a portion of the side of the first body <NUM>.

The organic layer <NUM> is not formed in at least a portion of the side of the second body <NUM> having the negative side slope. Hence, the organic layer <NUM> is physically broken around the first protrusion <NUM>. Namely, the continuity of the organic layer <NUM> is partially broken around the first protrusion <NUM>.

The encapsulation layer <NUM> is formed on the organic layer <NUM>. A first inorganic layer <NUM> of the encapsulation layer <NUM> is formed on the entire organic layer <NUM> and all the sides of the first protrusion <NUM> so that the first inorganic layer <NUM> covers both the sides of the first body <NUM> and the sides of the second body <NUM>. Thus, the first inorganic layer <NUM> is formed in a display area without a physically broken portion. The first inorganic layer <NUM> or a second inorganic layer <NUM> may be formed by a chemical vapor deposition (CVD) method or an atomic layer deposition method.

Every time a flexible display panel is bent, a stress is applied to each layer included in the OLED display panel. In particular, the organic layer <NUM> vulnerable to an adhesive strength may be peeled from the bank insulating layer <NUM> due to repeated stress.

In order to prevent the above-described problem, the first protrusion <NUM> featuring a second body having a negative side slope is disposed on the bank insulating layer <NUM>. As described above, the first protrusion <NUM> breaks the continuity of the organic layer <NUM> and thus minimizes diffusion of a peeling phenomenon generated in a specific area. Further, the inorganic layers <NUM> and <NUM> are formed on the organic layer <NUM>, in order to entirely cover the organic layer <NUM>. Because the inorganic layers <NUM> and <NUM> each have a good adhesive strength, the inorganic layers <NUM> and <NUM> tightly adhere the organic layer <NUM> to the substrate <NUM>.

The first inorganic layer <NUM> covers all the sides of the first protrusion <NUM> so that the first inorganic layer <NUM> is formed on the side of the second body <NUM> as well as the side of the first body <NUM>. Hence, the first inorganic layer <NUM> having the good adhesive strength can tightly adhere the organic layer <NUM> to the substrate <NUM> by simultaneously covering the organic layer <NUM> and the sides of the first protrusion <NUM>. As a result, the first inorganic layer <NUM> can tightly adhere the organic layer <NUM> to the substrate <NUM>, so that the organic layer <NUM> underlying the encapsulation layer <NUM> is not peeled from the bank insulating layer <NUM>.

The OLED display panel according to the embodiment of the disclosure can improve the adhesive strength of the organic layer <NUM> and prevent the peeling of the organic layer <NUM> in a folding area when a foldable display panel is implemented.

<FIG> is a cross-sectional view illustrating a structure of a luminescent display panel according to a comparative example that does not form part of the present invention but represents background art useful for understanding the invention. <FIG> is an enlarged view illustrating a portion of <FIG>.

In a luminescent display panel shown in <FIG>, a reverse spacer <NUM> having a negative side slope is directly disposed on a bank insulating layer <NUM>'. Subsequently, an organic layer <NUM>' and an inorganic layer <NUM>' are sequentially disposed on a first electrode <NUM>' exposed by an organic hole <NUM>, the bank insulating layer <NUM>', and the reverse spacer <NUM>. The inorganic layer <NUM>' is also formed on a side of the reverse spacer <NUM> having a negative side slope.

Referring to <FIG>, the inorganic layer <NUM>' may not be formed in a portion of an area B where the reverse spacer <NUM> and the bank insulating layer <NUM>' meet. As shown in the area B, the inorganic layer <NUM>' includes a vacancy not including an inorganic material. The inorganic layer <NUM>' in an area C may be thinner than the inorganic layer <NUM>' in other areas. A space of the area B where the reverse spacer <NUM> and the bank insulating layer <NUM>' meet is relatively narrower than spaces of other areas. In particular, in the areas B and C shown in <FIG>, the reverse spacer <NUM> and the bank insulating layer <NUM>' form an acute angle. In this case, a probability of diffusion of an inorganic material into the area B or C is further reduced in a process for depositing the inorganic layer <NUM>'. Hence, the inorganic layer <NUM>' may be deposited such that it does not have a uniform thickness or includes the vacancy as in the area B or C. As a result, the inorganic layer <NUM>' shown in <FIG> has difficulty in efficiently sealing the organic layer <NUM>'.

Referring to <FIG>, the OLED display panel includes the first protrusion <NUM> having the positive side slope on the bank insulating layer <NUM>. The first body <NUM> having the positive side slope can increase an angle of a position where the first protrusion <NUM> and the bank insulating layer <NUM> meet, compared to the angle formed by the reverse spacer <NUM> and the bank insulating layer <NUM>' according to the comparative example. Namely, because the side of the first body <NUM> and the bank insulating layer <NUM> form an obtuse angle, an inorganic material can be more easily diffused in a process for depositing the first inorganic layer <NUM>. The above-described structure according to <FIG> can further improve an adhesion force between the encapsulation layer <NUM> and the bank insulating layer <NUM>. In other words, because the embodiment of the invention sufficiently secures a space and an access path where the first protrusion <NUM> and the bank insulating layer <NUM> meet, this embodiment can uniformly deposit the inorganic material throughout the entire area.

The OLED display panel includes the first protrusion <NUM> having both the positive side slope and the negative side slope. The first protrusion <NUM> includes the first body <NUM> having the positive side slope and the second body <NUM> having the negative side slope. The second body <NUM> is configured such that the organic layer <NUM> is not formed on the side of the second body <NUM>, and thus partially breaks the continuity of the organic layer <NUM>. The center portion of the vertical cross section of the first protrusion <NUM> is depressed in an engraved shape. Namely, the first protrusion <NUM> has a structure in which a portion having a gradually decreasing width and a portion having a gradually increasing width are successively disposed. Hence, the first protrusion <NUM> causes the inorganic material to be uniformly deposited in an area where the first body <NUM> and the second body <NUM> meet and an area where the first body <NUM> and the bank insulating layer <NUM> meet. Thus, the OLED display panel according to the embodiment of the invention can further increase the adhesive strength of the organic layer <NUM> and further improve a sealing capability of the encapsulation layer <NUM>. As a result, the OLED display panel according to the embodiment of the invention is suitable for a flexible display which require high reliability and high specifications.

<FIG> is a cross-sectional view illustrating a structure of a luminescent display panel according to another comparative example that does not form part of the present invention but represents background art useful for understanding the invention. <FIG> enlargedly illustrates an area <NUM> shown in <FIG> and illustrates a structure of a luminescent display panel according to still another comparative example that does not form part of the present invention but represents background art useful for understanding the invention.

Referring to <FIG>, a first protrusion <NUM> may be disposed in a bank hole <NUM>. The bank hole <NUM> is an area, in which a bank insulating layer <NUM> (in other words, a bank <NUM>) is not formed, and exposes a second protective layer <NUM>. The bank hole <NUM> includes an organic layer broken portion. The first protrusion <NUM> may be disposed in the organic layer broken portion on the second protective layer <NUM>. A second protrusion <NUM> is disposed on the bank insulating layer <NUM>. In this instance, it is preferable, but not required, that a protruding degree of the second protrusion <NUM> from a substrate <NUM> is greater than a protruding degree of the first protrusion <NUM> from the substrate <NUM>.

An organic layer <NUM> may be disposed on a first electrode <NUM> and the first protrusion <NUM> as well as the bank insulating layer <NUM> having the bank hole <NUM> by which the second protective layer <NUM> is exposed. In particular, the organic layer <NUM> is formed on a side of the bank insulating layer <NUM> and a portion of a side of the first protrusion <NUM> having a positive side slope. However, the organic layer <NUM> is not formed in at least a portion of a side of the first protrusion <NUM> having a negative side slope.

The first protrusion <NUM> includes a first body <NUM> having a positive side slope. Because the side of the first protrusion <NUM> has the positive side slope, a first inorganic layer <NUM> can be uniformly formed on all the sides of the first protrusion <NUM> in a process for depositing the first inorganic layer <NUM>. Namely, the first inorganic layer <NUM> can be successively formed on a side of the first body <NUM> and a side of a second body <NUM> without a broken portion. Further, because the first protrusion <NUM> includes both the first body <NUM> having the positive side slope and the second body <NUM> that is disposed on the first body <NUM> and has the negative side slope, a probability that bubbles are included in the first inorganic layer <NUM> formed around the first protrusion <NUM> can be minimized. Hence, the first inorganic layer <NUM> can tightly fix the organic layer <NUM> to the substrate <NUM> so that the organic layer <NUM> is not peeled.

Referring to <FIG>, the second protective layer <NUM> of the bank hole <NUM> and the first protrusion <NUM> form an obtuse angle. Thus, a space for the inorganic layer is sufficient. Further, because an obtuse angle is formed at a position where the first body <NUM> and the second body <NUM> meet, the inorganic layer can be smoothly formed on the side of the first protrusion <NUM>. Namely, because a space to form the inorganic layer is sufficiently opened inside the bank hole <NUM>, there is no obstacle to diffusion of an inorganic material in a process for forming the first inorganic layer <NUM>. Thus, the first inorganic layer <NUM> can be formed with a uniform thickness in a formation area of the organic layer <NUM> and can be also evenly formed in an area where the organic layer <NUM> is not formed. Hence, because the first inorganic layer <NUM> is successively formed without the broken portion in all areas where an encapsulation layer <NUM> is formed, better encapsulation capability can be secured. Further, the peeling of the organic layer <NUM> can be minimized by tightly fixing the organic layer <NUM> to the substrate <NUM>.

Referring to <FIG>, a first protrusion <NUM> is disposed on a second protective layer <NUM> of a bank hole <NUM>. Namely, the first protrusion <NUM> is disposed on an organic layer broken portion not having an organic layer.

The first protrusion <NUM> includes a first body <NUM> and a second body <NUM> that is positioned on the first body <NUM> and has a negative side slope. The first body <NUM> may include the same material as a first electrode <NUM>, and the first body <NUM> and the first electrode <NUM> may be formed at the same time through the same process. Thus, because the first body <NUM> is formed without a separate mask, process time and process cost can be saved. Other materials may be used for the first body <NUM>. For example, the first body <NUM> may include a different material from the first electrode <NUM>.

The first protrusion <NUM> has an acute angle. Referring to <FIG>, an upper surface of the first body <NUM> and a side of the second body <NUM> form an acute angle. A portion ranging from the second protective layer <NUM> to the second body <NUM> via the side and the upper surface of the first body <NUM> has a stepped shape due to a formation of the first body <NUM>, and thus a space to deposit an inorganic material can be secured. Hence, a first inorganic layer <NUM> can be uniformly deposited in all of spaces of the bank hole <NUM> including the first protrusion <NUM>.

Claim 1:
A luminescent display panel comprising:
a substrate (<NUM>);
a first electrode (<NUM>) positioned on the substrate (<NUM>);
a bank (<NUM>) overlapping at least a portion of the first electrode (<NUM>);
a first protrusion (<NUM>) including a first body (<NUM>) positioned on the bank (<NUM>) and a second body (<NUM>) positioned on the first body (<NUM>);
a second protrusion (<NUM>) positioned on the bank (<NUM>) and not overlapping the first body (<NUM>) and the second body (<NUM>);
a first organic layer (<NUM>) positioned on the substrate (<NUM>) and overlapping the first electrode (<NUM>), the bank (<NUM>), an upper surface of the first protrusion (<NUM>) and an upper surface of the second protrusion (<NUM>); and
a second electrode (<NUM>) positioned on the substrate (<NUM>) and overlapping the first electrode (<NUM>), the bank (<NUM>), and the first organic layer (<NUM>),
wherein the first body (<NUM>) has a positive side slope, the second body (<NUM>) has a negative side slope and the second protrusion (<NUM>) has a positive side slope,
wherein as the second body (<NUM>) goes from a first surface contacting the first body (<NUM>) to a second surface opposite the first surface in a vertical direction, a cross-sectional area of the second body (<NUM>) increases,
wherein as the first body (<NUM>) goes from the first surface contacting the second body (<NUM>) to a third surface that is closer to the substrate (<NUM>) than the first surface, a cross-sectional area of the first body (<NUM>) increases,
wherein as the second protrusion (<NUM>) goes from a fourth surface to a fifth surface opposite to the fourth surface in a vertical direction, a cross-sectional area of the second protrusion (<NUM>) increases, wherein the fifth surface is closer to the substrate (<NUM>) than the fourth surface, and characterised in that the luminescent display panel is flexible or foldable and in that it comprises
an encapsulation layer (<NUM>) comprising a first inorganic layer (<NUM>) formed on the entire organic layer (<NUM>) and all the sides of the first protrusion (<NUM>) including the first body (<NUM>) and the second body (<NUM>) without a physically broken portion.