Patent Description:
In recent years, display screen technologies for electronic devices have developed rapidly, especially a bendable flexible screen has emerged, so that more product forms can be developed for the electronic devices, and a foldable-screen device is a currently emerging product form. At present, a display module of a foldable-screen device has a multi-layer stacked structure. The multi-layer stacked structure may include a support plate, a substrate, a display panel, and at least one protection layer sequentially from the bottom up. The support plate, the substrate, the display panel, and the at least one protection layer are attached together by using adhesive layers (for example, optically clear adhesives (optically clear adhesives, OCAs) and pressure-sensitive adhesives (pressure sensitive adhesives, PSAs)).

The display module includes at least one bendable region. The display module is configured to bend in the bendable region, thereby unfolding and folding a device body of the foldable-screen device. During bending of the display module, structures on layers of the display module generate internal stresses due to deformation and interaction. Under the action of the internal stresses, an originally attached state among the structures on the layers of the display module may be destroyed, resulting in structural peeling (peeling) between some layers. As a result, the display module is imprinted or damaged.

<CIT> discloses a display assembly and a display device, and aims at providing a supporting scheme of a flexible screen. <CIT> describes a foldable display device which includes a display panel including a folding part and a non-folding part, a plurality of middle frames disposed at the lower surface of the display panel, and a bottom case for receiving the display panel and the middle frames. <CIT> describes a foldable support, fabricating method thereof, and a display device.

Embodiments of this application provide a support assembly according to any of claims <NUM> to <NUM>, a display module according to claim <NUM>, and an electronic device according to claim <NUM>, to reduce an internal stress generated during bending of a display module of a foldable-screen device, thereby avoiding a peeling phenomenon, and improving reliability of the display module.

According to a first aspect, an embodiment of this application provides a support assembly, including: a support plate, a first adhesive layer, a substrate, and a second adhesive layer, where the support plate, the first adhesive layer, the substrate, and the second adhesive layer are stacked from the bottom up; the substrate is attached to the support plate by using the first adhesive layer, and the support assembly is configured to attach to another structure by using the second adhesive layer, thereby forming a display module of a foldable-screen device; the support assembly includes a bendable region; the support assembly is configured to bend in the bendable region; the support assembly is provided with a plurality of first holes in the bendable region; the plurality of first holes are distributed at intervals in an array; and the plurality of first holes penetrate through at least the support plate and the substrate in a stacking direction of the support plate, the first adhesive layer, the substrate, and the second adhesive layer.

According to the support assembly provided in this embodiment of this application, due to disposing of the first holes, at least the support plate and the substrate are hollowed out. This reduces an internal stress generated during bending of the support assembly and an internal stress exerted by the support assembly on another structure of the display module. Therefore, a status of attaching between structures on layers of the display module is prevented from being damaged by the internal stress; no peeling phenomenon occurs after the display module is bent; and reliability of the display module is improved.

The plurality of first holes penetrate through the support plate, the first adhesive layer, the substrate, and the second adhesive layer in the stacking direction. In this way, the first holes penetrate through the entire support assembly in the stacking direction, thereby effectively reducing internal stresses generated during bending of the support plate, the first adhesive layer, the substrate, and the second adhesive layer.

In an implementation, the first hole is a strip-shaped hole, and a length direction of the first hole is parallel to an axis of the bendable region of the support assembly; and the plurality of first holes are distributed at intervals in the array in directions parallel to the axis and directions perpendicular to the axis. Due to the strip-shaped holes, a larger hollowed-out area can be formed on the support assembly, thereby providing a larger deformation space for materials such as the support plate and the substrate, improving bending performance of the materials such as the support plate and the substrate, and reducing the internal stress generated during bending.

In an implementation, the support assembly is further provided with a plurality of second holes in the bendable region, and the plurality of second holes are distributed at intervals in an array; and the plurality of second holes are formed in a plate surface, back to the first adhesive layer, of the support plate, and form a specific depth H in the stacking direction, where the depth H is less than a thickness B of the support plate in the stacking direction. In this way, the second holes can be formed by performing hollowing out on the support plate in a region without the first holes, thereby improving bending performance of the support plate in the region without the first holes, and reducing the internal stress generated during bending.

In an implementation, the second hole is a strip-shaped hole, and a length direction of the second hole is parallel to the axis; the second hole continuously extends in a direction parallel to the axis from an end surface on one side of the support plate to an end surface on the other side of the support plate; and the plurality of second holes are distributed at intervals in the array in a direction perpendicular to the axis. Due to the strip-shaped holes, a larger hollowed-out area can be formed on the support plate, thereby providing a larger deformation space for the support plate, improving bending performance of the support plate, and reducing the internal stress generated during bending.

In an implementation, the bendable region includes an internally bendable region, the support assembly is configured to bend in the internally bendable region towards the second adhesive layer, and the plurality of first holes are formed in the internally bendable region.

In an implementation, the bendable region includes an externally bendable region, the support assembly is configured to bend in the externally bendable region towards the support plate, and the plurality of second holes are formed in the externally bendable region.

In an implementation, both the first adhesive layer and the second adhesive layer are pressure-sensitive adhesives.

According to a second aspect, an embodiment of this application provides a display module. The display module includes: the support assembly according to the first aspect of the embodiments of this application and each implementation of the first aspect, a display panel, a third adhesive layer, a first protection layer, a fourth adhesive layer, and a second protection layer, where the support assembly, the display panel, the third adhesive layer, the first protection layer, the fourth adhesive layer, and the second protection layer are stacked from the bottom up; and the display panel is attached to the substrate of the support assembly by using the second adhesive layer, the first protection layer is attached to the display panel by using the third adhesive layer, and the second protection layer is attached to the first protection layer by using the fourth adhesive layer.

The display module in this embodiment of this application has a smaller stress during bending. Therefore, a status of attaching between structures on layers of the display module is prevented from being damaged by the internal stress; no peeling phenomenon occurs after the display module is bent; and reliability of the display module is improved.

In an implementation, the display panel is an organic light-emitting diode OLED display panel.

In an implementation, both the third adhesive layer and the fourth adhesive layer are optically clear adhesives.

In an implementation, the first protection layer is a polarizing layer, and the second protection layer is ultra-thin glass or a clear polyimide film.

According to a third aspect, an embodiment of this application provides an electronic device. The electronic device includes one or more display modules, where at least one of the display modules is the display module according to the second aspect of the embodiments of this application and each implementation of the second aspect.

<NUM>: device body; <NUM>: display screen; <NUM>: support plate; <NUM>: display panel; <NUM>: cover plate; <NUM>: bendable region; <NUM>: plane region; <NUM>: internally bendable region; <NUM>: externally bendable region; <NUM>: support plate; <NUM>: substrate; <NUM>: display panel; <NUM>: first protection layer; <NUM>: second protection layer; <NUM>: pressure-sensitive adhesive; <NUM>: pressure-sensitive adhesive; <NUM>: optically clear adhesive; <NUM>: optically clear adhesive; <NUM>: support plate; <NUM>: first adhesive layer; <NUM>: substrate; <NUM>: second adhesive layer; <NUM>: first hole; <NUM>: second hole; <NUM>: display panel; <NUM>: third adhesive layer; <NUM>: first protection layer; <NUM>: fourth adhesive layer; and <NUM>: second protection layer.

In recent years, display screen technologies for electronic devices have developed rapidly, especially a bendable flexible screen has emerged, so that more product forms can be developed for the electronic devices, and a foldable-screen device is a currently emerging product form.

At present, foldable-screen devices may be classified into internally foldable-screen devices and externally foldable-screen devices based on different folding directions of display modules. <FIG> is a schematic diagram of a structure of a foldable-screen device according to an embodiment of this application. The structure a in <FIG> is a schematic diagram of a structure of an internally foldable-screen device. The structure b in <FIG> is a schematic diagram of a structure of an externally foldable-screen device. As shown in the structure a in <FIG>, the internally foldable-screen device is an electronic device whose device body <NUM> can be bent towards a side having a display module <NUM>. The display module <NUM> is hidden on an inner side of the device body <NUM> of the electronic device after the device body <NUM> of the electronic device is folded. Therefore, the following effect is achieved: The display module <NUM> is hidden when the device body <NUM> is in a folded state, and is displayed when the device body <NUM> is in an unfolded state. As shown in the structure b in <FIG>, the externally foldable-screen device is an electronic device whose device body <NUM> can be bent towards a back side of the device body <NUM>. The display module <NUM> surrounds an outer side of the device body <NUM> of the electronic device after the device body <NUM> of the electronic device is folded. Therefore, the following effect is achieved: The display module <NUM> surrounds the device body <NUM> to form a surrounding screen when the device body <NUM> is in a folded state, and forms a normally straight screen when the device body <NUM> is in an unfolded state.

<FIG> is a schematic diagram of an unfolded display module according to an embodiment of this application. As shown in <FIG>, the display module may include at least one bendable region <NUM>. A region other than the bendable region <NUM> is a plane region <NUM>. The bendable region <NUM> is a region in which the display module can be bent during bending of a device body of a foldable-screen device. The plane region <NUM> is a region in which the display module cannot be bent during bending of the device body of the foldable-screen device. A quantity of bendable regions <NUM> depends on a quantity of folds of the device body of the foldable-screen device. If the device body of the foldable-screen device is bent only once (namely, a single-foldable-screen device), the display module may include one bendable region <NUM>. If the device body of the foldable-screen device is bent twice (namely, a dual-foldable-screen device), the display module may include two bendable regions <NUM>. As an example, the display module shown in <FIG> includes one bendable region <NUM>. The plane regions <NUM> are disposed on the left and right sides of the bendable region <NUM>, so that the device body of the foldable-screen device can be bent leftwards or rightwards. The quantity of bendable regions <NUM> of the display module does not fall within a discussion scope of embodiments of this application, and thus is not further described below.

<FIG> uses an internally foldable-screen device as an example, and is a schematic diagram of a form of a display module of a foldable-screen device whose device body <NUM> is in a folded state. As shown in <FIG>, when the device body <NUM> is in the folded state, an internally bendable region <NUM> and externally bendable regions <NUM> may be formed at different locations of the bendable region. The internally bendable region <NUM> is a region in which the display module is bent towards an image-displaying side. The externally bendable region <NUM> is a region in which the display module is bent towards a side having a support plate. Whether the internally bendable region <NUM> or the externally bendable region <NUM> can be specifically formed in the bendable region depends on a bending direction of the device body <NUM> and structural design of a technical person. Therefore, distribution of the internally bendable region <NUM> and the externally bendable region <NUM> may be different in different foldable-screen devices. This is not limited in this embodiment of this application.

<FIG> is a schematic diagram of a structure of a display module of an existing foldable-screen device. As shown in <FIG>, the display module of the foldable-screen device has a multi-layer stacked structure. The multi-layer stacked structure may include a support plate <NUM>, a substrate <NUM>, a display panel <NUM>, a first protection layer <NUM>, and a second protection layer <NUM> sequentially from the bottom up. For example, the support plate <NUM> may be a TA4 titanium alloy plate; the substrate <NUM> may be a polyimide PI substrate; the display panel <NUM> may be a flexible organic light-emitting diode (Organic Light-Emitting Diode, OLED); the first protection layer <NUM> may be a polarizing layer (Polarizer); and the second protection layer <NUM> may be a cover plate. Further, a pressure-sensitive adhesive <NUM> is disposed between the support plate <NUM> and the substrate <NUM>, and the support plate <NUM> and the substrate <NUM> are attached together by using the pressure-sensitive adhesive <NUM>; a pressure-sensitive adhesive <NUM> is disposed between the substrate <NUM> and the display panel <NUM>, and the substrate <NUM> and the display panel <NUM> are attached together by using the pressure-sensitive adhesive <NUM>; an optically clear adhesive <NUM> is disposed between the display panel <NUM> and the first protection layer <NUM>, and the display panel <NUM> and the first protection layer <NUM> are attached together by using the optically clear adhesive <NUM>; and an optically clear adhesive <NUM> is disposed between the first protection layer <NUM> and the second protection layer <NUM>, and the first protection layer <NUM> and the second protection layer <NUM> are attached together by using the optically clear adhesive <NUM>. Generally, in actual production, a structure formed by the support plate <NUM>/pressure-sensitive adhesive <NUM>/substrate <NUM>/pressure-sensitive adhesive <NUM> usually exists as an independent assembly. For ease of description, this assembly is referred to as a support assembly in this application.

Further, as shown in <FIG>, hollowing out is performed on a bendable region of the support plate <NUM> of the display module, to reduce an internal stress generated during bending of the display module. Hollowing out the support plate <NUM> can reduce, to some extent, the internal stress generated during the bending of the display module. However, actual tests show that the internal stress generated during the bending of the display module is still very large. An internal stress exerted on the optically clear adhesive <NUM> between the display panel <NUM> and the first protection layer <NUM> is the largest. As a result, the optically clear adhesive <NUM> is prone to peel from the display panel <NUM> and the first protection layer <NUM> that are in an attached state, that is, peeling occurs, making the display module imprinted or damaged.

A first embodiment of this application is described below.

The first embodiment of this application provides a support assembly. The support assembly can further reduce the internal stress generated during the bending of the display module, to avoid peeling. <FIG> is a schematic diagram of a structure of the support assembly according to the first embodiment of this application. As shown in <FIG>, the support assembly includes a support plate <NUM>, a first adhesive layer <NUM>, a substrate <NUM>, and a second adhesive layer <NUM>. The support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> are stacked from the bottom up. Specifically:
The support plate <NUM> may be used as the bottommost layer of the support assembly, is generally made of a high-modulus plate, for example, TA4 titanium alloy, stainless steel, or polyvinyl alcohol (polyvinyl alcohol, PVA) high-modulus fiber, and may alternatively be made of a material having specific plasticity and rigidity. The support plate <NUM> is configured to support the display module and maintain a form of the display module when a device body of a foldable-screen device is in various folded/unfolded states.

The first adhesive layer <NUM> is disposed on the support plate <NUM>. For example, the first adhesive layer <NUM> may be an adhesive layer formed by a pressure-sensitive adhesive, or may be an adhesive layer formed by an optically clear adhesive.

The substrate <NUM> is disposed on the first adhesive layer <NUM>. The substrate <NUM> is attached to the support plate <NUM> by using the first adhesive layer <NUM>. For example, the substrate <NUM> may be a polyethylene terephthalate PET film, a polyimide PI substrate, or the like. The substrate <NUM> is used as a connection structure between the support assembly and another structure of the display module. A surface, facing the support plate <NUM>, of the substrate <NUM> is attached to the support plate <NUM> by using the first adhesive layer <NUM>. A surface, back to the support plate <NUM>, of the substrate <NUM> is configured to attach to another structure (for example, a display panel) of the display module.

The second adhesive layer <NUM> is disposed on the substrate <NUM>. For example, the second adhesive layer <NUM> may be an adhesive layer formed by a pressure-sensitive adhesive, or may be an adhesive layer formed by an optically clear adhesive. The support assembly is configured to attach to another structure of the display module by using the second adhesive layer <NUM>, thereby forming a complete display module of the foldable-screen device.

In this embodiment of this application, the first adhesive layer <NUM> is disposed on the surface, facing the support plate <NUM>, of the substrate <NUM>; and the second adhesive layer <NUM> is disposed on the surface, back to the support plate <NUM>, of the substrate <NUM>. Therefore, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> actually form a double-sided adhesive structure. It may be considered that the support plate <NUM> and the another structure of the display module are attached together by using a double-sided adhesive.

Specific implementations may be as follows: The first adhesive layer <NUM> and the second adhesive layer <NUM> are first coated or adhered to two sides of the substrate <NUM>, to form the double-sided adhesive; and then, the double-sided adhesive is attached to the support plate <NUM>. Alternatively, the first adhesive layer <NUM> is first coated or adhered to the support plate <NUM>; then, the substrate <NUM> is attached to the first adhesive layer <NUM>; and finally, the second adhesive layer <NUM> is coated or adhered to the surface, back to the support plate <NUM>, of the substrate <NUM>.

Further, as shown in <FIG>, the support assembly in this embodiment of this application is further provided with a hollowed-out structure. For example, the hollowed-out structure may be provided in a bendable region of the support assembly. The hollowed-out structure may include at least a plurality of first holes <NUM>. The plurality of first holes <NUM> are distributed in the bendable region of the support assembly at intervals in an array.

In this embodiment of this application, the first holes <NUM> may be through holes that are formed in the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM>, and penetrate through the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> sequentially in a stacking direction of the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> (may be a direction perpendicular to the support plate <NUM>), thereby penetrating through the entire support assembly. In this way, in the bendable region of the support assembly, material removal is performed on all of the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> of the support assembly by forming the first holes <NUM>, so that internal stresses of the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> generated during bending are reduced.

Further, when the bendable region of the support assembly includes an externally bendable region and an internally bendable region, the support assembly is generally bent in the internally bendable region by a smaller radius, leading to a larger bending degree. Therefore, the plurality of first holes <NUM> are preferentially distributed in the internally bendable region of the support assembly, to reduce internal stresses of portions, in the internally bendable region, of the support assembly and the display module.

Further, as shown in <FIG>, in an implementation, the hollowed-out structure further includes at least one second hole <NUM>. When the bendable region of the support assembly includes an externally bendable region and an internally bendable region, the at least one second hole <NUM> may be formed in the externally bendable region of the support assembly. When there are a plurality of second holes <NUM> in the externally bendable region, the plurality of second holes <NUM> are distributed at intervals in an array.

In a specific implementation, the second hole <NUM> may be a blind hole that is formed in a plate surface, back to the substrate <NUM>, of the support plate <NUM> and form a specific depth H in a direction of the substrate <NUM>. The depth H of the second hole <NUM> is less than a thickness B of the support plate <NUM>. In this case, when the support assembly is bent, the support plate <NUM> may have a larger deformation space in the externally bendable region. Therefore, an internal stress generated in the externally bendable region by the support plate <NUM> is smaller. This facilitates reducing an entire stress on portions, in the externally bendable region, of the support assembly and the display module. In addition, a plate surface, facing the substrate <NUM>, of the support plate <NUM> can still maintain a continuous structure in the externally bendable region. This also ensures structural strength of the externally bendable region.

In this embodiment of this application, the hollowed-out structure may be obtained by using a laser cutting process or an etching process in the support assembly.

For example, the hollowed-out structure may be manufactured after the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> are attached to form an integral structure. For example, after the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> are attached to form the integral structure, materials at locations at which the first holes <NUM> need to be formed are removed by using the laser cutting process with a cutting depth that is formed in one step and that penetrates through the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM>, thereby obtaining the first holes <NUM>.

For example, the hollowed-out structure may be manufactured before the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> are attached to form an integral structure. For example, before the support plate <NUM> is attached to the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM>, materials at locations at which the first holes <NUM> (and the second hole <NUM>) need to be formed in the support plate <NUM> may be removed by using the laser cutting process, thereby obtaining portions that are of the first holes <NUM> (and the second hole <NUM>) and that are in the support plate <NUM>. In addition, materials at locations at which the first holes <NUM> need to be formed in the double-sided adhesive formed by the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> may be removed by using the laser cutting process, to obtain portions that are of the first holes <NUM> and that are in double-sided adhesive. Finally, the support plate <NUM> that is provided with the first holes <NUM> (and the second hole <NUM>) and the double-sided adhesive that is provided with the first holes <NUM> are attached to form the support assembly having the hollowed-out structure.

In this embodiment of this application, the hollowed-out structure may be obtained by performing cutting based on a specific pattern (pattern).

<FIG> is a schematic diagram of a pattern of a hollowed-out structure according to an embodiment of this application. Based on a pattern shown in <FIG>, in an implementation, the first hole <NUM> may be, for example, a strip-shaped hole; a length direction of the first hole <NUM> is parallel to an axis L of the bendable region of the support assembly; and the plurality of first holes <NUM> are distributed at intervals in the array in directions parallel to the axis L and directions perpendicular to the axis L. In the directions parallel to the axis L and the directions perpendicular to the axis L, there is a specific interval between every two adjacent first holes <NUM>. In addition, in the directions parallel to the axis L, the plurality of first holes <NUM> are distributed from one end of the support plate <NUM> to the other end of the support plate <NUM>, so that any location of the support assembly in the directions parallel to the axis L has good bending performance. In addition, in the directions perpendicular to the axis L, the plurality of first holes <NUM> are distributed in a specific width range.

Further, as shown in <FIG>, in an implementation, the second hole <NUM> may be, for example, a strip-shaped hole; a length direction of the second hole <NUM> is parallel to an axis L of the bendable region of the support assembly; the plurality of second holes <NUM> are distributed at intervals in the array in a direction perpendicular to the axis L; and there is a specific interval between every two adjacent second holes <NUM>. Preferentially, a length of the second hole <NUM> is equal to a width that is of the support plate <NUM> and that is in a direction parallel to the axis L. In this way, the second hole <NUM> continuously extends in the direction parallel to the axis L from an end surface on one side of the support plate <NUM> to an end surface on the other side of the support plate <NUM>, thereby penetrating through the support plate <NUM> in the direction parallel to the axis L.

It can be learned that according to the support assembly provided in the first embodiment of this application, internal stresses of structures on layers of the support assembly are reduced due to a structure of the first holes, so that a stress exerted by the support assembly on another structure of the display module (for example, a stress exerted on an optically clear adhesive) is further reduced. Therefore, an attached state of the structures on the layers of the display module is prevented from being damaged by an excessive stress; no peeling phenomenon occurs after the display module is bent; and reliability of the display module is improved.

Another support assembly is described below.

The support assembly can further reduce the internal stress generated during the bending of the display module, to avoid peeling. <FIG> is a schematic diagram of a structure of the support assembly. As shown in <FIG>, the support assembly includes a support plate <NUM>, a first adhesive layer <NUM>, a substrate <NUM>, and a second adhesive layer <NUM>. The support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM> are stacked from the bottom up.

The support assembly differs from the support assembly in the first embodiment of this application in that:
A plurality of first holes <NUM> are formed in only the support plate <NUM> and the substrate <NUM>, and the first adhesive layer <NUM> and the second adhesive layer <NUM> are provided with no first hole <NUM>. On the support plate <NUM>, the first holes <NUM> extend from a plate surface, back to the substrate <NUM>, of the support plate <NUM> to a plate surface, facing the substrate <NUM>, of the support plate <NUM>, thereby penetrating through the support plate <NUM>. On the substrate <NUM>, the first holes <NUM> extend from a surface, facing the support plate <NUM>, of the substrate <NUM> to a surface, back to the support plate <NUM>, of the substrate <NUM>, thereby penetrating through the substrate <NUM>. Being provided with no first hole <NUM>, the first adhesive layer <NUM> is coated entirely between the support plate <NUM> and the substrate <NUM>. Being provided with no first hole <NUM>, the second adhesive layer <NUM> is coated entirely on the surface, back to the support plate <NUM>, of the substrate <NUM>.

In this embodiment of this application, material removal is performed on the support plate <NUM> and the substrate <NUM> of the support assembly by forming the first holes <NUM>, so that during bending of the support assembly, the support plate <NUM> and the substrate <NUM> can obtain larger deformation spaces. This facilitates release of internal stresses, and reduces internal stresses of structures on layers of the support assembly.

In this embodiment of this application, the first holes <NUM> may be formed in the support plate <NUM> and the substrate <NUM> by using a laser cutting process or an etching process.

For example, the first holes <NUM> may be formed before the support plate <NUM> is attached to the substrate <NUM>. For example, before the support plate <NUM> is attached to the substrate <NUM>, materials at locations at which first holes <NUM> need to be formed in the support plate <NUM> may be removed by using the laser cutting process, thereby obtaining portions that are of the first holes <NUM> and that are in the support plate <NUM>. In addition, before an adhesive layer is coated on the substrate <NUM>, materials at locations at which the first holes <NUM> need to be formed in the substrate <NUM> may be removed by using the laser cutting process, thereby obtaining portions that are of the first holes <NUM> and that are in the substrate <NUM>. Then, the first adhesive layer <NUM> is coated or adhered to the substrate <NUM> that is provided with the first holes <NUM>. Finally, the support plate <NUM> that is provided with the first holes <NUM> and the substrate <NUM> that is provided with the first holes <NUM> are attached by using the first adhesive layer <NUM>, to form an integral structure.

For example, the first holes <NUM> may be formed after the support plate <NUM> is attached to the substrate <NUM>. For example, the first adhesive layer <NUM> may be first coated or adhered to the substrate <NUM>, so that the support plate <NUM> and the substrate <NUM> are attached by using the first adhesive layer <NUM> to form an integral structure. Then, the laser cutting process or the etching process is performed on the integral structure that is formed after the support plate <NUM> and the substrate <NUM> are attached, to remove materials at locations at which the first holes <NUM> need to be formed in the support plate <NUM> and the substrate <NUM>, thereby obtaining the first holes <NUM> in the support plate <NUM> and the first holes <NUM> in the substrate <NUM>.

For other features that are not described in detail in this example, reference may be made to the first embodiment of this application.

It can be learned that according to the support assembly described above, the internal stresses of the structures on the layers of the support assembly are reduced due to a structure of the first holes, so that a stress exerted by the support assembly on another stacked structure of the display module is further reduced. Therefore, a status of attaching between the structures on the layers of the display module is prevented from being damaged by an excessive stress; no peeling phenomenon occurs after the display module is bent; and reliability of the display module is improved.

A third embodiment of this application is described below.

The third embodiment of this application provides a display module. Compared with a conventional bendable display module, the display module in the third embodiment of this application has a smaller internal stress during bending, so that peeling can be avoided.

<FIG> is a schematic diagram of a structure of the display module according to the third embodiment of this application. As shown in <FIG>, the display module includes: the support assembly according to the first embodiment of this application and each implementation of the first embodiment, a display panel <NUM>, a third adhesive layer <NUM>, a first protection layer <NUM>, a fourth adhesive layer <NUM>, and a second protection layer <NUM>. The support assembly, the display panel <NUM>, the third adhesive layer <NUM>, the first protection layer <NUM>, the fourth adhesive layer <NUM>, and the second protection layer <NUM> are stacked from the bottom up. Specifically:.

The support assembly may be used as the bottommost layer of the display module. As shown in <FIG>, the support assembly may include: a support plate <NUM>; a first adhesive layer <NUM> disposed on the support plate <NUM>; a substrate <NUM> disposed on the first adhesive layer <NUM>, where the substrate <NUM> is attached to the support plate <NUM> by using the first adhesive layer <NUM>; a second adhesive layer <NUM> disposed on the substrate <NUM>; and first holes <NUM> penetrating through the support plate <NUM>, the first adhesive layer <NUM>, the substrate <NUM>, and the second adhesive layer <NUM>, and/or second holes <NUM> formed in the support plate <NUM>.

The display panel <NUM> is disposed on the second adhesive layer <NUM>. The display panel <NUM> is attached to the substrate <NUM> by using the second adhesive layer <NUM>. The display panel <NUM> is configured to display an image. For example, the display panel <NUM> may be a flexible organic light-emitting diode (Organic Light-Emitting Diode, OLED) display panel or another flexible display panel such as a flexible micro-LED display panel or a mini-LED display panel.

The third adhesive layer <NUM> is disposed on the display panel <NUM>. For example, the third adhesive layer <NUM> may be an adhesive layer formed by an optically clear adhesive, or may be an adhesive layer formed by a pressure-sensitive adhesive.

The first protection layer <NUM> is disposed on the third adhesive layer <NUM>. The first protection layer <NUM> is attached to the display panel <NUM> by using the third adhesive layer <NUM>. For example, the first protection layer <NUM> may be a polarizing layer (Polarizer).

The fourth adhesive layer <NUM> is disposed on the first protection layer <NUM>. For example, the fourth adhesive layer <NUM> may be an adhesive layer formed by an optically clear adhesive, or may be an adhesive layer formed by a pressure-sensitive adhesive.

The second protection layer <NUM> is disposed on the fourth adhesive layer <NUM>. The second protection layer <NUM> is used as a cover plate of the display module, and may be made of a material such as ultra-thin glass or a clear polyimide film, thereby having good bending performance.

<FIG> is a schematic diagram of a simulated bending test of a display module according to an embodiment of this application. As shown in <FIG>, the following may be performed to verify that the display module in this embodiment of this application has a capability of reducing an internal stress generated during bending: Simulating bending of the display module in a case that a device body of an internally foldable-screen device is in a folded state; and selecting some sampling points for internal stress sampling. Because a third adhesive layer usually bears the largest internal stress, two sampling points are selected from the third adhesive layer in this embodiment of this application, which are P1 at an external rounded corner in a region of a second hole <NUM> and P2 at an internal rounded corner in the region of the second hole <NUM>. In addition, two sampling points are also selected from the fourth adhesive layer in this embodiment of this application, which are P3 at an external rounded corner in the region of the second hole <NUM> and P4 at an internal rounded corner in the region of the second hole <NUM>. Sampling results are shown in Table <NUM>.

It can be learned from Table <NUM> that, at the external rounded corner in the region of the second hole, an internal stress born by the third adhesive layer is reduced by <NUM>% than that of the conventional display module solution, and an internal stress born by the fourth adhesive layer is reduced by <NUM>% than that of the conventional display module solution; and at the internal rounded corner in the region of the second hole, an internal stress born by the third adhesive layer is reduced by <NUM>% than that of the conventional display module solution, and an internal stress born by the fourth adhesive layer is reduced by <NUM>% than that of the conventional display module solution.

It can be learned that the display module in the third embodiment of this application has a smaller stress during bending. Therefore, a status of attaching between structures on layers of the display module is prevented from being damaged by the internal stress; no peeling phenomenon occurs after the display module is bent; and reliability of the display module is improved.

Another example display module is described below.

Compared with a conventional bendable display module, the display module in this example has a smaller internal stress during bending, so that peeling can be avoided.

<FIG> is a schematic diagram of a structure of the display module. As shown in <FIG>, the display module includes: the support assembly of <FIG>, a display panel <NUM>, a third adhesive layer <NUM>, a first protection layer <NUM>, a fourth adhesive layer <NUM>, and a second protection layer <NUM>. The support assembly, the display panel <NUM>, the third adhesive layer <NUM>, the first protection layer <NUM>, the fourth adhesive layer <NUM>, and the second protection layer <NUM> are stacked from the bottom up. Specifically:
The support assembly may be used as the bottommost layer of the display module. As shown in <FIG>, the support assembly may include: a support plate <NUM>; a first adhesive layer <NUM> disposed on the support plate <NUM>; a substrate <NUM> disposed on the first adhesive layer <NUM>, where the substrate <NUM> is attached to the support plate <NUM> by using the first adhesive layer <NUM>; a second adhesive layer <NUM> disposed on the substrate <NUM>; and first holes <NUM> penetrating through the support plate <NUM> and the substrate <NUM>, and/or second holes <NUM> formed in the support plate <NUM>.

The display panel <NUM> is disposed on the second adhesive layer <NUM>. The display panel <NUM> is attached to the substrate <NUM> by using the second adhesive layer <NUM>. The display panel <NUM> is configured to display an image. For example, the display panel <NUM> may be a flexible organic light-emitting diode OLED display panel or another flexible display panel such as a flexible micro-LED display panel or a mini-LED display panel.

The first protection layer <NUM> is disposed on the third adhesive layer <NUM>. The first protection layer <NUM> is attached to the display panel <NUM> by using the third adhesive layer <NUM>. For example, the first protection layer <NUM> may be a polarizing layer.

Table <NUM> shows results of simulated bending tests and sampling performed on the display module in this example in a manner of a simulated bending test and sampling that are shown in <FIG>.

It can be learned that the display module described above has a smaller stress during bending. Therefore, a status of attaching between structures on layers of the display module is prevented from being damaged by the internal stress; no peeling phenomenon occurs after the display module is bent; and reliability of the display module is improved.

An embodiment of this application further provides an electronic device. For example, the electronic device may be a foldable-screen device, a rollable-screen device, or any electronic device with a bendable display screen. The electronic device may include one or more display modules, where at least one of the display modules is the display module according to the third embodiment, or at least one of the display modules includes the support assembly according to the first embodiment of this application or any implementation of the first embodiment. For example, the electronic device may be an internally foldable-screen device. The internally foldable-screen device may include an internal screen module and an external screen module. The internal screen module is a display module that is hidden when a device body is in a folded state. The external screen module is a display module that is always exposed regardless of the device body's state. The internal screen module is the display module in the third embodiment.

Claim 1:
A support assembly, comprising:
a support plate (<NUM>), a first adhesive layer (<NUM>), a substrate (<NUM>), and a second adhesive layer (<NUM>), wherein
the support plate, the first adhesive layer, the substrate, and the second adhesive layer are stacked from the bottom up;
the substrate is attached to the support plate by using the first adhesive layer, and the support assembly is configured to attach to another structure by using the second adhesive layer, thereby forming a display module of a foldable-screen device; and
the support assembly comprises a bendable region, the support assembly is configured to bend in the bendable region, the support assembly is provided with a plurality of first holes (<NUM>) in the bendable region, the plurality of first holes are distributed at intervals in an array, and the plurality of first holes penetrate through at least the support plate and the substrate in a stacking direction of the support plate, the first adhesive layer, the substrate, and the second adhesive layer;
characterized in that the plurality of first holes penetrate through the support plate, the first adhesive layer, the substrate, and the second adhesive layer in the stacking direction.