KR20230148783A - Stretchable flexible printed circuit board - Google Patents

Abstract

A stretchable flexible printed circuit board according to an embodiment may include a core portion and a protective layer surrounding the core portion and formed of a material having elasticity. The core portion is disposed to be spaced apart from the first elastic base film pattern with a first elastic core portion including a first stretchable base film pattern in contact with the first metal wiring portion and a protective layer therebetween, and the second metal wiring portion and the second metal wiring portion. It may include a second elastic core portion including a second elastic base film pattern in contact. The protective layer may cover the top, bottom, left, and right sides of each of the first and second elastic core portions. Accordingly, a stretchable flexible printed circuit board whose length in the stretching direction can be increased can be provided.

Description

STRETCHABLE FLEXIBLE PRINTED CIRCUIT BOARD}

The present invention relates to flexible printed circuit boards. More specifically, it relates to stretchable flexible printed circuit boards.

A display device is a device that outputs electrical signals in visual form. Recently, with the expansion of smart devices including smartphones, demand for display devices is rapidly increasing in the technology field related to portable electronic devices such as tablet PCs (personal computers), smart watches, mobile communication terminals, electronic notebooks, and e-books. In addition, there is a lot of demand for display devices in the technology field related to large-screen display devices such as TVs, laptops, monitors, billboards, etc.

Conventional display devices are simple flat display devices without any physical modifications to the display itself, but recently, display devices capable of exhibiting flexible characteristics are being developed.

Examples of display devices that exhibit flexible characteristics include bendable display devices and rollable display devices. Additionally, recently, foldable display devices and, furthermore, stretchable display devices that can be stretched and shrunk in a specific direction are on the rise.

Exemplary display devices may meet market characteristics in that demand for large-screen display devices may require characteristics of portability that can be easily carried.

In order to drive the light emitting device of a display device, a driving circuit, wiring, and a printed circuit board (PCB) including all of them are required.

A PCB may be placed behind the display area to reduce the non-display area, or so-called bezel area, while simultaneously improving portability. In this structure, a flexible printed circuit board (FPCB) is used to reduce the size of the bezel.

The FPCB can also function as a sensor. In the case of a stretchable display device, if the sensing FPCB is not stretched during the process of stretching the liquid crystal panel, a large difference may occur between the actual touch input position and the sensing coordinates. This may result in malfunctions during the coordinate recognition process.

One object of the present invention is to provide a flexible printed circuit board that can be stretched.

The object of the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

A stretchable flexible printed circuit board according to an embodiment may include a core portion and a protective layer surrounding the core portion and formed of a material having elasticity.

In one embodiment, the core portion is spaced apart from the first stretchable base film pattern with the first stretchable core portion including the first stretchable base film pattern in contact with the first metal wiring portion and the protective layer therebetween. It may include a second elastic core portion disposed and including a second elastic base film pattern in contact with the second metal wiring portion.

In one embodiment, the protective layer may cover the top, bottom, left, and right sides of each of the first and second elastic core parts.

In one embodiment, at least a portion of the first elastic core portion includes a first zigzag pattern, and at least a portion of the second elastic core portion includes a second zigzag pattern, wherein the second zigzag pattern forms the protective layer. It is disposed to be spaced apart from the first zigzag pattern, and is electrically separated from the first zigzag pattern, and each of the first and second zigzag patterns may include a bending portion.

In one embodiment, each of the first and second stretchable base film patterns may have a pattern corresponding to the first and second metal wiring portions.

In one embodiment, each of the first and second stretchable base film patterns may include a groove, and each of the first and second metal wiring portions may have a structure embedded in the first and second grooves.

The first elastic base film, the second elastic base film, and the protective layer are made of urethane, silicone, rubber, nylon, styrene, liquid crystal polymer (LCP), epoxy resin, fluorine resin, and polyethylene. It may be formed including at least one selected from the group consisting of PE), polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN).

A stretchable flexible printed circuit board according to an embodiment of the present invention can provide a flexible printed circuit board whose length in the stretching direction can be extended.

By including a protective layer, the metal wiring portion may not be exposed to chemicals used in the board manufacturing process or set assembly process, and thus physical/chemical damage can be prevented. The protective layer may not be processed, and thus, in the process of attaching the protective layer to the elastic core portion, alignment may be facilitated and attachment time may be shortened.

The elastic base film pattern may be formed of a material containing at least one selected from the group consisting of polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). Accordingly, adhesion to the wiring portion can be improved on the surface in contact with the metal wiring portion. Cracks or disconnections that may occur in the wiring section can be prevented, and the elongation rate in the stretching direction can be increased.

As grooves are formed in the stretchable base film pattern, the metal wiring portion properly fixed by the grooves may not deviate from the base film pattern during the stretching process.

Since the present invention includes a zigzag pattern, when the stretching operation of the stretchable flexible printed circuit board is performed, the stretchable core portion can be stretched together in synchronization with the operation. Specifically, since the zigzag pattern includes a bending portion, the elastic core portion can be unfolded in the stretching direction. During the stretching process of the substrate, the bending portion becomes gentler and the elastic core portion can unfold as a whole. Accordingly, the length of the substrate in the direction to be stretched may be extended.

A stretchable flexible printed circuit board performs a coordinate function as a sensing substrate and can be stretched in synchronization with a stretchable display device. Accordingly, the role of reducing the occurrence of errors in coordinate recognition at the rear of the panel of the display device can be performed. In addition, the substrate used in parts where flexible printed circuit boards are typically mounted can be replaced with the stretchable flexible printed circuit board.

Figure 1 is a partially cut away perspective view of a stretchable flexible printed circuit board according to an embodiment of the present invention.
Figure 2 is a cross-sectional view of a stretchable flexible printed circuit board according to an embodiment of the present invention.
Figure 3 is a longitudinal cross-sectional view of a stretchable flexible printed circuit board according to an embodiment of the present invention.
Figure 4 is a longitudinal cross-sectional view of a stretchable flexible printed circuit board according to an embodiment of the present invention.
Figure 5 is a longitudinal cross-sectional view showing modified embodiments of a processed cross-section of a stretchable base film pattern.
Figure 6 is a cross-sectional view of a stretchable flexible printed circuit board formed with a continuous elastic core portion.
Figure 7 is a cross-sectional view showing modified embodiments of a stretchable flexible printed circuit board formed with a continuous elastic core portion.
Figure 8 is a cross-sectional view showing that a stretchable flexible printed circuit board can be applied as a replacement for the sensing FPCB.
Figure 9 is a flowchart for explaining the manufacturing method of a stretchable flexible printed circuit board.

The meaning of terms described in this specification should be understood as follows.

Singular expressions should be understood to include plural expressions unless the context clearly defines otherwise, and terms such as “first” and “second” are used to distinguish one element from another element. The scope of rights should not be limited by these terms.

Terms such as “include,” “have,” or “equipped” do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. It must be understood.

The term “at least one” should be understood to include all possible combinations from one or more related items. For example, “at least one of the first, second, and third items” means each of the first, second, or third items, as well as two of the first, second, and third items. It means a combination of all items that can be presented from more than one.

The term “at least a portion” should be interpreted as being able to refer to all parts, from the minimum to the maximum, of an object.

The term “on” means not only the case where a certain component is formed directly on top of another component, but also the case where a third component is interposed between these components.

The term “pattern” does not necessarily mean that a shape is arranged repeatedly, but rather means any non-repetitive shape. For example, the pattern of a metal wiring portion does not refer only to repetitive parts of the metal wiring portion, but refers to all shapes in which the wiring portion is drawn.

Hereinafter, a stretchable flexible printed circuit board and a manufacturing method thereof according to an embodiment of the present invention will be described in detail with reference to the attached drawings. In adding reference numerals to components in each drawing, identical components may have the same reference numerals as much as possible even if they are shown in different drawings. Additionally, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a partially cut away perspective view of a stretchable flexible printed circuit board according to an embodiment of the present invention.

Referring to FIG. 1, a stretchable flexible printed circuit board 100 (hereinafter abbreviated as SFPCB 100) according to an embodiment of the present invention includes a core portion 200 and a protective layer. It may include (400).

Referring to the coordinate system of FIG. 1, the x-direction can be defined as the horizontal or width direction, the y-direction can be defined as the vertical or longitudinal direction, and the z-direction can be defined as the thickness direction.

The direction in which arbitrary planes parallel to the xz plane are viewed in the +y or -y direction may be the side or cross-section direction of the SFPCB 100 according to one embodiment.

The direction in which arbitrary planes parallel to the yz plane are viewed in the +x or -x direction may be the side or longitudinal cross-section direction of the SFPCB 100 according to one embodiment.

The direction in which arbitrary planes parallel to the xy plane are viewed in the +z or -z direction may be the plane or cross-section direction of the SFPCB 100 according to one embodiment.

The SFPCB (100) has an upper surface located on the upper side, a lower surface located on the lower side, a front side located at the front of the cross section, a rear side located at the back, and a left side and a right side located on the left side of the longitudinal section based on the core portion 200. It may include the right side where it is located.

In Figure 1, only a portion of the SFPCB 100, including its longitudinal cross section, is shown. The SFPCB 100 can be completely implemented by expanding this in the length direction (+y, -y) and/or width direction (+x, -x).

The protective layer 400 may surround the core portion 200. The shape of the core portion 200 may be a hexahedron including the top, bottom, left side, right side, front, and back, but is not limited thereto. The function of the core portion 200 can be protected by the protective layer 400 from any physical or chemical external force and/or external pressure.

In the SFPCB 100 according to an embodiment of the present invention, the protective layer 400 is not processed, so when attached to the elastic core portion 210, alignment is easy and attachment time can be shortened.

The protective layer 400 may be formed of an elastic material. Materials with elasticity are not particularly limited, but include urethane, silicone, rubber, nylon, styrene, liquid crystal polymer (LCP), epoxy resin, fluorine resin, polyethylene (PE), and polyimide. , PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN).

The core portion 200 may include a first elastic core portion 210 and a second elastic core portion 260. The second elastic core portion 260 may be spaced apart from the first elastic core portion 210 and disposed with the protective layer 400 interposed therebetween.

The first elastic core portion 210 and the second elastic core portion 260 may be implemented as adjacent wires that are electrically separated from each other with the protective layer 400 interposed therebetween.

Each of the first elastic core portion 210 and the second elastic core portion 260 may have a structure in which patterns are connected to each other. For example, the first elastic core portion 210 is shown in a vertical cross-section as spaced apart with the protective layer 400 interposed between them, but may have a three-dimensional structure connected to each other.

Hereinafter, for convenience of explanation, the description will focus on the first elastic core portion 210. The description regarding the first elastic core portion 210 may be applied to all elastic core portions including the second elastic core portion 260. For example, the following descriptions regarding the first stretchable base film pattern 230 and the first zigzag pattern 240 can be equally applied to the second stretchable base film pattern 280 and the second zigzag pattern 290, respectively. there is.

As described above, the core portion 200 may include the elastic core portion 210. The elastic core portion 210 may include a stretchable base film pattern 230 and a metal wiring portion 220.

If the SFPCB 100 is viewed from the left side in the +x direction, ignoring the protective layer 400, the elastic core portion 210 may have a three-dimensional stepped structure. The step may be formed because the stretchable base film pattern 230 is longer in the width direction than the metal wiring portion 220. The three-dimensional step structure visible from the left side of the SFPCB (100) described above may have a shape in which the base film pattern 230 protrudes further toward the left side of the SFPCB (100).

The protective layer 400 may cover the top/bottom and side surfaces of the stretchable base film pattern 230 and the top/bottom and sides of the metal wiring portion 220 in the elastic core portion 210 in which the step is formed. Accordingly, the protective layer 400 protects the elastic core portion 210 in all directions and allows it to be stretched. Since the metal wiring portion 220 is surrounded by the protective layer 400, the metal wiring portion 220 may not be exposed to chemicals used in the board manufacturing process or set assembly process, and thus may not be exposed to physical/chemical chemicals. Damage can be prevented.

The elastic base film pattern 230 may be formed of a material that has elasticity. Materials with elasticity are not particularly limited, but include urethane, silicone, rubber, nylon, styrene, liquid crystal polymer (LCP), epoxy resin, fluorine resin, polyethylene (PE), and polyimide. , PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN).

Preferably, it may be made of a material containing at least one selected from the group consisting of polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN).

When the base film pattern 230 is formed using the above material, adhesion to the metal wiring portion 220 may be improved on the surface that contacts the metal wiring portion 220. Cracks or disconnections that may occur in the wiring portion 220 can be prevented, and the elongation rate in the stretching direction can be increased.

The materials of the elastic base film pattern 230 and the protective layer 400 may be the same or different from each other. If the materials are different, the difference in elasticity may increase and affect the elongation of the SFPCB (100). Regardless of whether the materials are the same or different, the elasticity of the elastic base film pattern 230 and the elasticity of the protective layer 400 may be the same or different from each other.

If there is a difference in elasticity, the elasticity of the SFPCB 100 may be different from the elasticity of the elastic base film pattern 230 and the elasticity of the protective layer 400.

SFPCB (100) according to an embodiment of the present invention may have an elongation of 10% to 200%. Within the above range, the SFPCB 100 can be appropriately stretched in response to a stretchable display device, and when used as a sensing FPCB, the sensing effect can be improved. Specifically, when the stretchable display device is stretched, the SFPCB 100, which can serve as a coordinate, can be stretched in synchronization with the display device. Accordingly, it can play a role in reducing the occurrence of errors in coordinate recognition at the rear of the panel.

The elongation rate can be defined by Equation 1 below.

The direction in which the SFPCB 100 according to one embodiment is stretched may not be limited. Referring to FIG. 1, although not particularly limited thereto, the SFPCB 100 may be stretched in the +x, -x, +y, or -y directions.

FIG. 2 is a view in the -z direction of the area where the elastic core portion 210 of the SFPCB 100 is cut along the plane including line A-A' among arbitrary planes parallel to the xy plane in FIG. 1. It is a cross-sectional view. In Figure 2, the second elastic core portion 260 is omitted. 2 also shows a portion of the flexible core portion 210.

FIG. 3 is a longitudinal cross-sectional view of the SFPCB 100 cut along a plane including line B-B' among arbitrary planes parallel to the xz plane in FIG. 2, viewed in the -y direction.

FIG. 4 is a longitudinal cross-sectional view of the SFPCB 100 cut along a plane including line C-C' among arbitrary planes parallel to the xz plane in FIG. 2, viewed in the -y direction. Figure 4 also shows a portion of the bending portion 241.

FIG. 5 is a cross-sectional view showing modified embodiments of the processing cross-section 232 substantially the same as FIG. 3 .

Referring to FIGS. 2, 3, and 4, the stretchable base film pattern 230 may include a groove 231.

The groove 231 may be formed by removing a portion of the base film. The groove 231 may be formed on the upper surface along the +z direction and/or the lower surface along the -z direction of the elastic base film pattern 230.

The shape of the groove 231 is not limited, and since the metal wiring portion 220 is disposed in the groove 231, it may have substantially the same width, length, and thickness as the metal wiring portion 220. For example, if the metal wiring portion 220 has a circular cross-sectional shape, the groove 231 may also have a circular shape. Additionally, in this case, the groove 231 may have a cross-section large enough to properly insert a portion of the metal wiring portion 220.

Referring to FIG. 3, the groove 231 may have a depth in the +z and/or -z directions. At least a portion of the metal wiring portion 220 may be seated below the upper surface of the stretchable base film pattern 230 by the depth of the groove 231 .

The width of the groove 231 in the x-direction may be substantially the same as that of the metal wiring portion 220. A groove 231 may be formed in the base film pattern 230 corresponding to the pattern of the metal wiring portion 220. The stretchable base film pattern 230 may have a pattern corresponding to the metal wiring portion 220.

The metal wiring portion 220 may be in contact with the stretchable base film pattern 230 based on the surface included in the stretchable base film pattern 230 where the base film pattern 230 and the groove 231 are in contact. In one embodiment, the metal wiring portion 220 may have a structure embedded in the groove 231 .

Accordingly, the metal wiring portion 220 may be fixed to the base film pattern 230. Accordingly, when the SFPCB 100 is stretched or stretched, the metal wiring portion 220 properly fixed by the groove 231 may not be separated from the base film pattern 230.

The stretchable base film pattern 230 may include a machined cross-section 232.

The processed cross-section 232 may be formed by removing at least a portion of the base film. The base film may be in a state before at least a portion of the base film is removed before the base film pattern 230 is formed.

A method for removing at least a portion of the base film may be a method well known in the art, and a laser method or an etching method may be used. Preferably, the base film is etched using an etching method to form the processed cross-section 232 on the stretchable base film pattern 230.

The processing cross-section 232 may be a plane including an imaginary line dividing the inner space 242 and the base film pattern 230.

The shapes of the processed cross sections 235 and 236 may not be constant in the length, thickness, and width directions of the SFPCB (100). The shape of the processed cross-section 232 is not limited thereto, but may have a shape that is, for example, etched once in the substantially z-direction or etched twice in the substantial -z and -x directions.

Figure 6 is a cross-sectional view of the SFPCB 100 implemented by continuously forming elastic core portions 210 and 260. Specifically, part of the protective layer 400 disposed on the upper surface is omitted so that the metal wiring portions 220 and 270 and the elastic base film patterns 230 and 280 are exposed in the z direction, and the SFPCB 100 is exposed in the planar direction. This is a cross-sectional view viewed in the -z direction.

Figure 6A shows SFPCB 100 before stretching and Figure 6B shows SFPCB 100 after stretching.

Figure 7 is a cross-sectional view showing modified embodiments of the SFPCB 100 substantially the same as Figure 6.

Referring to Figures 6 and 7, continuous elastic core portions 210 and 260 are formed. A protective layer 400 (not shown) is located between the first elastic core portion 210 and the second elastic core portion 260, and both core portions 210 and 260 may be arranged to be spaced apart from each other.

At least a portion of the base film may be removed corresponding to the pattern in which the metal wiring portion 220 is drawn. As a removal method, the same method as the method for forming the machined cross-section 232 can be used as described above.

A protective layer 400 may be disposed on the removed portion (not shown). The removed portion where the protective layer 400 is disposed may be the inner space 242.

The elastic core portion 210 may include a zigzag pattern 240. Referring to FIG. 6, the zigzag pattern 240 may mean a shape that extends alternately toward the +y direction and the -y direction in the planar direction of the SFPCB 100.

For example, referring to FIG. 7C, the first zigzag pattern 240 _{is not necessarily directed only in the positive y or -y direction, but forms an angle θ 1 with the -y direction or an angle θ 2 with} the +y direction. It can be drawn alternately in the x-direction. The θ ₁ and θ ₂ may be the same or different from each other.

By including the zigzag pattern 240, when the stretching operation of the SFPCB 100 is performed, the elastic core portion 210 can be stretched or stretched together in synchronization with the operation.

The zigzag pattern 240 may include a bending portion 241. The bending portion 241 may refer to a portion where the direction of bending is maintained constant and the direction of the pattern changes from the +y side to the -y side or from the -y side to the +y side.

The bending portion 241 is not particularly limited thereto, but may have a shape including an arbitrary straight line parallel to the +x direction in which the metal wiring portion 220 pattern of FIG. 7A is drawn. Alternatively, the curve may have an angular shape, such as the first zigzag pattern 240 of FIG. 7B. Alternatively, the curves may be rounded, such as the second zigzag pattern 290 of FIG. 7B.

Referring to the second zigzag pattern 290 of FIG. 7C, the shapes of the bending portions 291 within one zigzag pattern may not all be the same.

By including the bending portion 241, the elastic core portion 210 can be unfolded in the stretching direction. Specifically, during the stretching process, the curve of the bending portion 241 becomes gentle and the elastic core portion 210 may unfold as a whole. Accordingly, the SFPCB 100 may be extended in the direction in which it is stretched.

The zigzag pattern 240 may include an inner space 242. The inner space 242 may refer to a space where a portion of the base film is removed corresponding to the pattern in which the metal wiring portion 220 is drawn. Referring to the second zigzag pattern 290 of FIG. 7C, the inner space 292 may be formed to correspond to the pattern in which the metal wiring portion 270 including the irregular shape of the bending portion 241 is drawn.

A protective layer 400 surrounding the metal wiring portion 220 and the base film pattern 230 may be disposed in the inner space 242. Since the protective layer 400 is not processed, the attachment time during the placement process can be shortened.

In some embodiments, the SFPCB 100 may include a base film pattern 230 and a zigzag pattern 240 including grooves corresponding to the pattern of the metal wiring portion 220. Specifically, the inner space 242 in which the protective layer 400 made of an elastic material can be disposed may also be formed to correspond to the pattern of the metal wiring portion 220.

During the stretching process, the shape of the inner space 242 may be deformed. Accordingly, when the SFPCB 100 is stretched, a stretching operation may be performed in accordance with the stretching direction and stretching rate. For example, referring to FIG. 6B, when the SFPCB 100 is stretched in the +x direction, the inner space 242 decreases in length in the y direction as the metal wiring portion 220 advances in the +y direction and increases in the x direction. The width may increase.

Referring to FIGS. 7A to 7C , the first and second zigzag patterns 240 and 290 may be arranged to be spaced apart from each other with a protective layer 400 therebetween and may be electrically separated.

The SFPCB 100 according to some embodiments may be attached to the elastic core portion 210 without the protective layer 400 being processed. More specifically, the SFPCB 100 may be formed by entirely applying or adhering the protective layer 400 to the base film pattern 230 in an already processed state. Accordingly, registration is easy to prevent registration defects, and the attachment time of the protective layer 400 is shortened, thereby improving productivity.

Figure 8 is a cross-sectional view showing that a stretchable flexible printed circuit board can be applied as a replacement for the sensing FPCB.

Referring to FIG. 8 , when the stretchable display panel 500 is stretched, the SFPCB 100 may be stretched together in synchronization with the stretching operation. For example, when the stretchable display panel 500 is stretched in the x-direction, the SFPCB 100 may also be stretched in the x-direction in synchronization with the stretching operation.

Accordingly, when a user inputs a touch to the display panel 500 using a pen, coordinates may be recognized in the SFPCB 100 corresponding to the location where the touch is input. Through the above process, malfunctions that occur during the coordinate recognition process can be reduced.

In addition to replacing the sensing FPCB described above, the SFPCB 100 according to one embodiment can be used to replace the FPCB in parts where the FPCB is normally mounted. For example, the FPCB connected to the drive IC can be replaced with the SFPCB (100) according to an embodiment of the present invention.

Figure 9 is a flow chart for explaining the manufacturing method of SFPCB (100). The elastic base film may be in a state in which at least a portion of the elastic base film is removed before the elastic base film pattern 230 is formed.

Referring to FIG. 9, a stretchable base film is formed, and a groove 231 is formed corresponding to the area where the metal wiring portion 220 will be placed (eg, S1, S2). The groove 231 is formed by removing the base film as described above, and any removal method known in the art may be used.

For example, referring to S3, the elastic base film is removed to form an inner space 242 in an appropriate space among the remaining areas, excluding the area where the metal wiring portion 220 will be formed. .

Through this, the elastic base film pattern 230 can be implemented. As a removal method, any means readily available to those skilled in the art is possible, but etching may be preferable.

The metal wiring portion 220 is mounted on the elastic base film corresponding to the groove 231 (eg, S4).

Tack welding is performed to temporarily attach the protective layer 400 to the elastic base film pattern 230, and a lamination process is performed to completely cure it (eg, S5).

Although embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made without departing from the technical spirit of the present invention. . Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. The scope of protection of the present invention should be interpreted in accordance with the claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of rights of the present invention.

100: Stretchable flexible printed circuit board
200: Core part
210: first elastic core portion
220: First metal wiring part
230: first stretchable base film pattern
231: 1st groove
232: First machining cross section
240: first zigzag pattern
241: first bending part
242: first medial space
260: second elastic core portion
270: Second metal wiring unit
280: Second stretchy base film pattern
281: Second home
282: Second machining cross section
290: Second zigzag pattern
291: second bending part
292: Second medial space
400: protective layer
500: Stretchable display panel

Claims (5)

core part; and
It includes a protective layer surrounding the core portion and formed of an elastic material,
The core part,
a first elastic core portion including a first elastic base film pattern in contact with the first metal wiring portion; and
a second elastic core portion disposed to be spaced apart from the first elastic base film pattern with the protective layer interposed therebetween, and including a second elastic base film pattern in contact with a second metal wiring portion;
The protective layer is,
A stretchable flexible printed circuit board surrounding the top, bottom, left, and right sides of each of the first and second elastic core portions. According to claim 1,
At least a portion of the first elastic core portion includes a first zigzag pattern,
At least a portion of the second elastic core portion includes a second zigzag pattern,
The second zigzag pattern is disposed to be spaced apart from the first zigzag pattern with the protective layer interposed therebetween, and is electrically separated from the first zigzag pattern,
A stretchable flexible printed circuit board, wherein each of the first and second zigzag patterns includes a bending portion. According to clause 2,
A stretchable flexible printed circuit board, wherein each of the first and second stretchable base film patterns has a pattern corresponding to the first and second metal wiring portions. According to claim 1,
A stretchable flexible printed circuit wherein each of the first and second stretchable base film patterns includes first and second grooves, and each of the first and second metal wiring portions is embedded in the first and second grooves. Board. According to claim 1,
The first elastic base film, the second elastic base film, and the protective layer are made of urethane, silicone, rubber, nylon, styrene, liquid crystal polymer (LCP), epoxy resin, fluorine resin, and polyethylene. A stretchable flexible printed circuit comprising at least one selected from the group consisting of PE), polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). Board.