KR102354108B1 - Touch panel and junction structure of the touch sensor and flexible printed circuit board - Google Patents

Abstract

The present invention relates to a bonding structure of a touch panel and a flexible printed circuit board.
The present invention is formed in a touch panel, a flexible printed circuit board, and a first bonding area on a bonding pad part provided in the touch panel and a second bonding area extending from an end of the bonding pad part to form the touch panel and the flexible printed circuit board. It includes a joint that joins the
According to the present invention, since deformation that may occur in the components of the touch panel in the process of bonding the touch panel and the flexible printed circuit board is prevented, deterioration of the performance of the touch panel is prevented and bonding between the touch panel and the flexible printed circuit board The structural stability of the structure is ensured.

Description

Joint structure of touch panel and flexible printed circuit board

The present invention relates to a bonding structure between a touch panel and a flexible printed circuit board. More specifically, the present invention prevents the deterioration of the performance of the touch panel by preventing deformation that may occur in the components of the touch panel in the process of bonding the touch panel and the flexible printed circuit board, and between the touch panel and the flexible printed circuit board. It relates to a technology capable of securing the structural stability of a bonding structure.

A touch panel is an input device that enables a user to input a command by selecting instructions displayed on a screen of an image display device, etc. with a human hand or a pen, and has recently been applied to various information processing devices. Such a touch panel has advantages in that it is easy to operate, has few malfunctions, and is manufactured integrally with an image display device to enhance portability of the product.

The touch panel may be classified into a resistive film method, a capacitive method, a surface ultrasonic method, an infrared method, etc. according to a method for sensing a touched part, and the resistive film method and the capacitive method are mainly used.

The resistance film method consists of a structure in which two substrates coated with transparent electrodes are bonded together, and when the upper and lower electrode layers come into contact by applying pressure with a finger or pen, an electrical signal is generated to recognize the position. In the case of such a resistive film method, the price is low, the detection accuracy is high, and it is advantageous for miniaturization, but there is a difficulty in making it robustly because the touch is recognized only when two substrates are physically in contact.

On the other hand, the capacitive method uses a transparent substrate coated with a thin conductive material. When a certain amount of current flows on the surface of the transparent substrate and the user touches the coated surface of the transparent substrate, a certain amount of current is absorbed into the user's body. The touched part is checked by recognizing the part where the current amount of the contact surface is changed.

On the other hand, in general, a touch panel is bonded to a flexible printed circuit board (Flexible Printed Circuit Board) through an anisotropic conductive film (ACF), and various problems occur in connection with this bonding. Referring to FIG. 2 , these problems will be described.

1 is a view showing a planar shape of a conventional touch panel, and FIG. 2 is a view showing a bonding structure between a conventional touch panel and a flexible printed circuit board.

1 and 2 , a conventional touch panel 110 includes an adhesive layer 20 formed on a base film 10 , a protective layer 30 formed on the adhesive layer 20 , and a protective layer 30 formed on the protective layer 30 . It is configured to include a touch sensor unit 40 , a connection line unit 50 , and a bonding pad unit 70 .

The touch sensor unit 40 performs a function of detecting a touch signal input from the user, and the connection line unit 50 performs a function of electrically connecting the touch sensor unit 40 and the bonding pad unit 70, , the bonding pad part 70 is adhered to the flexible printed circuit board 200 via the anisotropic conductive film 350 . The touch signal sensed by the touch sensor unit 40 is transmitted to a driving unit (not shown) through the flexible printed circuit board 200 . The bonding pad unit 70 is provided with unit bonding pads 70 - 1 and 70 - 2 respectively electrically connected to connection lines constituting the connection line unit 50 . Reference numerals 71 and 74 of FIG. 2 denote indium tin oxide (ITO), and reference numeral 72 denotes a metal layer, which is formed on the bonding pad part 70 in the process of forming the touch sensor part 40 . In particular, the ITO formed thereon performs a function of a unit bonding pad constituting the bonding pad unit 70 .

As described above, since the bonding pad unit 70 of the touch panel has a complicated stack-up structure, the adhesive force and tensile force of the flexible printed circuit board 200 adhered to the bonding pad unit 70 is reduced, and the touch panel There is a problem in that the structural stability of the

Republic of Korea Patent Publication No. 10-2016-0007060 (published date: January 20, 2016, title: touch screen device and manufacturing method thereof)

The present invention improves bonding strength and tensile strength and secures structural stability of the bonding structure by using the outer terminal area of the bonding pad, which has an uncomplicated laminate structure, as the bonding area in the process of bonding the touch panel and the flexible printed circuit board. make it a technical task.

The bonding structure of the touch panel and the flexible printed circuit board according to the present invention includes a touch panel, a flexible printed circuit board, and a first bonding area on the bonding pad unit provided in the touch panel and a second bonding area extending from the end of the bonding pad unit. and a bonding portion formed in the junction for bonding the touch panel and the flexible printed circuit board.

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, the extension length of the second bonding area is 300 μm or more and 1000 μm or less.

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, the touch panel positioned below the second bonding area is laminated with functional layers including a base film, an adhesive layer, a first protective layer, and an insulating layer. It is characterized in that it has a structured structure.

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, the bonding portion is characterized in that it includes an anisotropic conductive film (ACF) or an anisotropic conductive material layer.

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, the touch panel includes an adhesive layer formed on a base film, a first protective layer formed on the adhesive layer, and a touch formed on the first protective layer A bonding pad unit including a plurality of unit bonding pads formed on the first protective layer in a state of being electrically connected to the sensor unit and the touch sensor unit and extending from the unit bonding pad while filling a spaced area between the unit bonding pads and an insulating layer formed on the first protective layer.

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, the unit bonding pad includes a plurality of insulator pillars having a height corresponding to the insulating layer and a transparent conductive layer formed on the insulator pillars characterized in that

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, a height difference between the unit bonding pad and the insulating layer is substantially equal to a thickness of the transparent conductive layer.

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, the insulating layer and the insulating pillars included in the unit bonding pad are formed through the same process.

In the bonding structure of the touch panel and the flexible printed circuit board according to the present invention, the touch panel may further include a second protective layer formed on an outer portion of the insulating layer to be spaced apart from the unit bonding pad.

According to the present invention, in the process of bonding the touch panel and the flexible printed circuit board, by using the outer terminal area of the bonding pad, which has an uncomplicated laminate structure, as the bonding area, the bonding strength and tensile strength are improved and the structural stability of the bonding structure is secured. has the effect of being

1 is a view showing a planar shape of a conventional touch panel,
2 is a view showing a bonding structure of a conventional touch panel and a flexible printed circuit board,
3 is a view showing a planar shape of a touch panel according to an embodiment of the present invention;
4 is a view showing a bonding structure of a touch panel and a flexible printed circuit board according to an embodiment of the present invention.
5 is a graph showing a change in tensile force according to an extension length of a second bonding region according to an embodiment of the present invention.

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification are only exemplified for the purpose of explaining the embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention are It may be implemented in various forms and is not limited to the embodiments described herein.

Since the embodiments according to the concept of the present invention may have various changes and may have various forms, the embodiments will be illustrated in the drawings and described in detail herein. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosed forms, and includes all modifications, equivalents, or substitutes included in the spirit and scope of the present invention.

Terms such as first or second may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another, for example without departing from the scope of the inventive concept, a first component may be termed a second component and similarly a second component A component may also be referred to as a first component.

When a component is referred to as being “connected” or “connected” to another component, it is understood that the other component may be directly connected or connected to the other component, but other components may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle. Other expressions describing the relationship between components, such as "between" and "immediately between" or "neighboring to" and "directly adjacent to", etc., should be interpreted similarly.

The terms used herein are used only to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or combination thereof described herein exists, but one or more other features It should be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present specification. does not

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

3 is a view showing a planar shape of a touch panel according to an embodiment of the present invention, and FIG. 4 is a view showing a bonding structure of a touch panel and a flexible printed circuit board according to an embodiment of the present invention.

3 and 4 , the bonding structure between the touch panel and the flexible printed circuit board according to an embodiment of the present invention includes a touch panel 100 , a flexible printed circuit board 200 , and a bonding part 300 .

The touch panel 100 includes a base film 10 , an adhesive layer 20 , a first protective layer 30 , a touch sensor unit 40 , a connection line unit 50 , a bonding pad unit 70 , an insulating layer ( 80) and a second protective layer 90 .

The base film 10 is adhered to the first protective layer 30 via the adhesive layer 20 , and functions as a base of the touch panel 100 .

For example, the base film 10 may be a transparent optical film or a polarizing plate.

As the transparent optical film, a film having excellent transparency, mechanical strength, and thermal stability may be used, and specific examples thereof include polyester-based resins such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, and polybutylene terephthalate; Cellulose resins, such as a diacetyl cellulose and a triacetyl cellulose; polycarbonate-based resin; acrylic resins such as polymethyl (meth)acrylate and polyethyl (meth)acrylate; styrenic resins such as polystyrene and acrylonitrile-styrene copolymer; polyolefin-based resins such as polyethylene, polypropylene, polyolefin having a cyclo-based or norbornene structure, and an ethylene-propylene copolymer; vinyl chloride-based resin; amide-based resins such as nylon and aromatic polyamide; imide-based resin; polyether sulfone-based resin; sulfone-based resins; polyether ether ketone-based resins; sulfide polyphenylene-based resin; vinyl alcohol-based resin; vinylidene chloride-based resin; vinyl butyral-based resin; allylate-based resin; polyoxymethylene-based resins; and a film composed of a thermoplastic resin such as an epoxy-based resin, and a film composed of a blend of the above-mentioned thermoplastic resins can also be used. In addition, a film made of a thermosetting resin or ultraviolet curable resin such as (meth)acrylic, urethane, acrylic urethane, epoxy, or silicone may be used. The thickness of such a transparent optical film may be appropriately determined, but in general, in consideration of workability such as strength or handleability, thin layer properties, etc., it may be determined to be 1 to 500 µm. In particular, 1-300 micrometers is preferable, and 5-200 micrometers is more preferable.

Such a transparent optical film may contain one or more suitable additives. Examples of the additive include a UV absorber, an antioxidant, a lubricant, a plasticizer, a mold release agent, a color inhibitor, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a colorant, and the like. The transparent optical film may have a structure including various functional layers such as a hard coating layer, an anti-reflection layer, and a gas barrier layer on one or both sides of the film, and the functional layer is not limited to the above, and various functional layers are provided according to the use. may include

In addition, if necessary, the transparent optical film may be surface-treated. Examples of such surface treatment include chemical treatment such as plasma treatment, corona treatment, dry treatment such as primer treatment, and alkali treatment including saponification treatment.

In addition, the transparent optical film may be an isotropic film or a retardation film.

In the case of an isotropic film, the in-plane retardation (Ro, Ro=[(nx-ny)×d], nx, ny is the principal refractive index in the plane of the film, and d is the film thickness.) is 40 nm or less, preferably 15 nm or less, and the thickness Direction retardation (Rth, Rth = [(nx+ny)/2-nz] x d, nx, ny is the principal refractive index in the film plane, nz is the refractive index in the film thickness direction, and d is the film thickness.) is -90 nm to + 75 nm, preferably -80 nm to +60 nm, particularly preferably -70 nm to +45 nm.

The retardation film is a film produced by uniaxial stretching, biaxial stretching, polymer coating, and liquid crystal coating of a polymer film, and is generally used to improve and control optical properties such as compensation for viewing angle of a display, improvement of color, improvement of light leakage, and control of color taste do. The retardation film includes a 1/2 or 1/4 wave plate, a positive C plate, a negative C plate, a positive A plate, a negative A plate, and a biaxial wave plate.

As the polarizing plate, a known polarizing plate used for a display panel may be used. Specifically, one made by stretching a polyvinyl alcohol film and installing a protective layer on at least one surface of a polarizer dyed with iodine or a dichroic dye, one made by aligning the liquid crystal to have the performance of the polarizer, polyvinyl film on a transparent film and coatings with an orientation resin such as alcohol and stretching and dyeing the same, but is not limited thereto.

The adhesive layer 20 performs a function of adhering the base film 10 and the first protective layer 30 .

As a material of the adhesive layer 20, a light-curable adhesive, a water-based adhesive, an organic-based adhesive, etc. may be used, but is not limited thereto.

The photocurable adhesive is an adhesive that is cured when irradiated with light such as UV. Since the photocurable adhesive does not require a separate drying process after photocuring, the manufacturing process is simple and productivity is improved.

For example, as the photocurable adhesive, a radical polymerization type containing acrylate, unsaturated polyester, etc. as main components, and a cationic polymerization type containing epoxy, oxetane, vinyl ether, etc. as main components may be used.

The first protective layer 30 is adhered to the base film 10 via the adhesive layer 20 , and serves as a base on which the components of the touch sensor unit 40 and the bonding pad unit 70 are formed. perform the function

As a material of the first protective layer 30, a polymer known in the art may be used without limitation, for example, an organic insulating film may be applied, and among them, a polyol and a melamine curing agent. It may be formed of a curable composition, but is not limited thereto.

Specific examples of the polyol include, but are not limited to, polyether glycol derivatives, polyester glycol derivatives, and polycaprolactone glycol derivatives.

Specific types of the melamine curing agent include methoxy methyl melamine derivatives, methyl melamine derivatives, butyl melamine derivatives, isobutoxy melamine derivatives, and butoxy melamine. derivatives, and the like, but are not limited thereto.

As another example, the first protective layer 30 may be formed of an organic-inorganic hybrid curable composition, and when an organic compound and an inorganic compound are used at the same time, it is preferable in that cracks occurring during peeling can be reduced. .

The above-mentioned components may be used as the organic compound, and the inorganic material may include, but is not limited to, silica-based nanoparticles, silicon-based nanoparticles, glass nanofibers, and the like.

The touch sensor unit 40 is formed on the first protective layer 30 and performs a function of sensing a touch signal input from a user.

For example, the touch sensor unit 40 may include a first transparent conductive pattern, a second transparent conductive pattern, an insulating layer, and a bridge pattern.

The first transparent conductive pattern may be formed in a first direction in a state of being electrically connected to each other, and the second transparent conductive pattern may be formed in a state in which the unit cells are electrically separated from each other and formed along the second direction. The direction may be a direction crossing the first direction. For example, when the first direction is the X direction, the second direction may be the Y direction.

The insulating layer may be formed between the first transparent conductive pattern and the second transparent conductive pattern, and electrically insulate the first transparent conductive pattern and the second transparent conductive pattern.

The bridge pattern electrically connects the adjacent second transparent conductive patterns.

As the first and second transparent conductive patterns, any transparent conductive material may be used without limitation, for example, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), florin tin oxide (FTO), indium tin oxide-silver-indium tin oxide (ITO-Ag-ITO), indium zinc oxide-silver-indium zinc oxide (IZO-Ag-IZO) ), metal oxides selected from the group consisting of indium zinc tin oxide-silver-indium zinc tin oxide (IZTO-Ag-IZTO) and aluminum zinc oxide-silver-aluminum zinc oxide (AZO-Ag-AZO); metals selected from the group consisting of gold (Au), silver (Ag), copper (Cu), molybdenum (Mo) and APC; nanowires of a metal selected from the group consisting of gold, silver, copper and lead; Carbon-based materials selected from the group consisting of carbon nanotubes (CNT) and graphene; and poly (3,4-ethylenedioxythiophene) (PEDOT) and polyaniline (PANI) may be formed of a material selected from the group consisting of conductive polymer materials, which may be used alone or in mixture of two or more, Preferably, indium tin oxide may be used. Both crystalline or amorphous indium tin oxide can be used.

For example, the first and second transparent conductive patterns may each independently be a triangular, quadrangular, pentagonal, hexagonal, or heptagonal or more polygonal pattern.

Also, for example, the first and second transparent conductive patterns may include a regular pattern. The regular pattern means that the shape of the pattern has regularity. For example, the sensing patterns may each independently include a mesh shape such as a rectangle or a square, or a pattern shape such as a hexagon.

Also, for example, the first and second transparent conductive patterns may include irregular patterns. The irregular pattern means that the shape of the pattern does not have regularity.

Also, for example, when the sensing patterns constituting the first and second transparent conductive patterns are formed of a material such as a metal nanowire, a carbon-based material, or a polymer material, the sensing patterns may have a network structure. When the sensing patterns have a network structure, signals are sequentially transmitted to adjacent patterns in contact with each other, thereby realizing a pattern having high sensitivity.

For example, the first and second transparent conductive patterns may be formed of a single layer or a plurality of layers.

An insulating material known in the art may be used without limitation as a material for the insulating layer insulating the first and second transparent conductive patterns, for example, a photosensitive resin composition including a metal oxide such as silicon oxide or an acrylic resin, or A thermosetting resin composition may be used. Alternatively, the insulating layer may be formed using an inorganic material such as silicon oxide (SiOx), and in this case, may be formed by deposition, sputtering, or the like.

The connection line unit 50 performs a function of electrically connecting the touch sensor unit 40 and the bonding pad unit 70 . For example, the connection line unit 50 connects each pattern constituting the first and second transparent conductive patterns and each unit bonding pad 70-1 and 70-2 constituting the bonding pad unit 70 . may be configured to electrically connect.

The bonding pad unit 70 includes a plurality of unit bonding pads 70-1 and 70- formed on the first protective layer 30 while being electrically connected to the touch sensor unit 40 via the connection line unit 50 as a medium. 2) is included.

For example, the unit bonding pads 70 - 1 and 70 - 2 may include a plurality of insulator pillars 73 having a height corresponding to the insulating layer 80 , and a conductive layer ( ) formed on the insulator pillars 73 . 74) may be included. With this configuration, since the step difference between the unit bonding pads 70 - 1 and 70 - 2 and the first insulating layer 80 is reduced corresponding to the thickness of the conductive layer 74 , the unit bonding pads 70 - 1, 70-2), the adhesion between the bonding pad portion 70 and the flexible printed circuit board (not shown) is improved.

The insulating layer 80 is formed on the first protective layer 30 so as to extend from the unit bonding pads 70-1 and 70-2 while filling the spaced area between the unit bonding pads 70-1 and 70-2. is formed

For example, in order to shorten the process time and reduce the number of required processes, the insulating layer 80 and the insulating pillars 73 included in the unit bonding pads 70-1 and 70-2 are formed through the same process. It can be configured to be

For example, a height difference between the unit bonding pads 70 - 1 and 70 - 2 and the insulating layer 80 may be configured to be substantially equal to the thickness of the conductive layer 74 , and the second protective layer 90 may be configured to be substantially the same as the thickness of the conductive layer 74 . ) may be configured to be formed in the outer portion of the insulating layer 80 to be spaced apart from the unit bonding pads 70-1 and 70-2, and the entire area of the unit bonding pads 70-1 and 70-2. and a partial region of the insulating layer 80 extending from the unit bonding pads 70-1 and 70-2 may be configured to be a bonding region for bonding with a flexible printed circuit board (FPCB). have.

The first transparent conductive layer 71 and the metal pattern 72 may be formed in the process of forming the touch sensor unit 40 . In addition, the conductive layer 74 formed on the insulator pillars 73 may also be formed in the process of forming the touch sensor unit 40 , and may be referred to as the second transparent conductive layer 74 in the order in which they are formed. For example, the first transparent conductive layer 71 and the second transparent conductive layer 74 may be made of a transparent conductive material such as ITO.

The second protective layer 90 is formed on the outer portion of the insulating layer 80 to be spaced apart from the unit bonding pads 70 - 1 and 70 - 2 . The second protective layer 90 is a component that is also formed on the bonding pad part 70 in the same way to suppress the occurrence of a step when the protective film is formed on the touch sensor part 40 .

The flexible printed circuit board 200 is bonded to the bonding pad portion 70 of the touch panel 100 and the region extending from the end of the bonding pad portion 70 via the bonding portion 300 .

The bonding unit 300 is formed in the first bonding area R1 on the bonding pad unit 70 provided in the touch panel 100 and the second bonding area R2 extending from the end of the bonding pad unit 70 to touch the touch panel 100 . The panel 100 and the flexible printed circuit board 200 are bonded.

For example, the bonding part 300 may include an anisotropic conductive film (ACF) or an anisotropic conductive material layer.

For example, the touch panel positioned under the second bonding region R2 includes functional layers including a base film 10 , an adhesive layer 20 , a first protective layer 30 , and an insulating layer 80 . It may have a simple stacked structure, and by extending the bonding area between the touch panel 100 and the flexible printed circuit board 200 to the second bonding area R2, the touch panel 100 and the flexible printed circuit board 200 Structural stability of the bonding structure can be secured by improving the bonding force between the joints and improving the tensile strength of the bonding portion 300 . For example, in order to secure sufficient bonding strength, the extended length L of the second bonding region R2 may be 300 μm or more and 1000 μm or less.

Tables 1 and 5 below are data of tensile force change according to the extension length L of the second junction region R2 according to an embodiment of the present invention.

Extension length (㎛) Tensile force of Experimental Example 1 (gf/cm) Tensile force of Experimental Example 2 (gf/cm) Tensile force of Experimental Example 3 (gf/cm) 0 471 350 380 100 457 421 431 200 469 487 451 250 489 499 511 300 612 644 681 500 634 723 659 750 734 781 711 1000 789 812 881

Referring to Table 1 and FIG. 5 , in the three experimental examples, it can be seen that the tensile force increases in proportion to the extended length L of the second bonding region R2 to which the bonding portion 300 is extended and bonded. Specifically, according to Experimental Example 1, when the extension lengths L of the second bonding region R2 were 300 μm and 1000 μm, respectively, the tensile forces were measured to be 612 gf/cm and 789 gf/cm, respectively, and in Experiment 2 Accordingly, when the extension length L of the second bonding region R2 was 300 μm and 1000 μm, respectively, the tensile forces were measured to be 644 gf/cm and 812 gf/cm, respectively, and according to Experimental Example 3, the second bonding region ( When the extension length (L) of R2) was 300 μm and 1000 μm, respectively, the tensile force was measured to be 681 gf/cm and 881 gf/cm, respectively. When the extension length L of the second bonding region R2 is 300 μm or more, a tensile force suitable for securing structural stability of the bonding structure between the touch panel 100 and the flexible printed circuit board 200 can be obtained. can check that In addition, according to the experimental data, the tensile force increases in proportion to the extension length L of the second junction region R2, but increasing the extension length L imposes design restrictions due to an increase in the outer margin, so the upper limit is preferably limited to 1000 μm.

The effect according to this configuration will be described in comparison with the prior art.

Referring to FIG. 2 , since the anisotropic conductive film 350 as an adhesion means is mainly formed on the bonding pad part 70 having a complicated lower structure, the adhesive force between the touch panel 110 and the flexible printed circuit board 200 and There is a problem in that the tensile force of the anisotropic conductive film 350 is lowered and the structural stability of the bonding structure is lowered.

However, according to an embodiment of the present invention, the bonding portion 300 includes not only the first bonding area R1 on the bonding pad unit 70 , but also the second bonding area R2 extending from the end of the bonding pad unit 70 . Since it is sufficiently formed over the touch panel 100 and the flexible printed circuit board 200 and the tensile force of the bonding portion 300 is stably secured, the structural stability of the bonding structure can be secured.

As described in detail above, according to the present invention, in the process of bonding the touch panel and the flexible printed circuit board, the terminal outer region of the bonding pad part, which has an uncomplicated laminate structure, is used as the bonding area, thereby improving bonding strength and tensile strength, and improving bonding strength and bonding structure. Structural stability is secured.

10: base film
20: adhesive layer
30: first protective layer
40: touch sensor unit
50: connection line part
70: bonding pad part
70-1, 70-2: unit bonding pad
71: first transparent conductive layer
72: metal pattern
73: insulator column
74: second transparent conductive layer
80: insulating layer
90: second protective layer
100: touch panel
200: flexible printed circuit board
300: junction
R1: first junction region
R2: second junction region
L: the extended length of the second bonding region

Claims (9)

touch panel;
flexible printed circuit boards; and
a bonding portion formed in a first bonding area on the bonding pad unit provided in the touch panel and a second bonding area extending from an end of the bonding pad unit to bond the touch panel and the flexible printed circuit board;
The extension length of the second bonding region is 300 μm or more and 1000 μm or less,
The touch panel is
an adhesive layer formed on the base film;
a first protective layer formed on the adhesive layer;
a touch sensor unit formed on the first protective layer;
a bonding pad unit including a plurality of unit bonding pads formed on the first protective layer while being electrically connected to the touch sensor unit; and
and an insulating layer formed on the first protective layer to extend from the unit bonding pad while filling the spaced area between the unit bonding pads.
A bonding structure between a touch panel and a flexible printed circuit board. delete According to claim 1,
The touch panel positioned under the second bonding area has a structure in which functional layers including a base film, an adhesive layer, a first protective layer, and an insulating layer are laminated, the touch panel and the flexible printed circuit board junction structure. According to claim 1,
Wherein the bonding portion comprises an anisotropic conductive film (Anisotropic Conductive Film, ACF) or an anisotropic conductive material layer, the bonding structure of the touch panel and the flexible printed circuit board. delete According to claim 1,
The unit bonding pad,
a plurality of insulator pillars having a height corresponding to the insulating layer; and
A bonding structure of a touch panel and a flexible printed circuit board, characterized in that it comprises a transparent conductive layer formed on the insulator pillars. 7. The method of claim 6,
A height difference between the unit bonding pad and the insulating layer is substantially the same as the thickness of the transparent conductive layer, the bonding structure of the touch panel and the flexible printed circuit board. 7. The method of claim 6,
The bonding structure of the touch panel and the flexible printed circuit board, characterized in that the insulation pillars included in the insulation layer and the unit bonding pad are formed through the same process. According to claim 1,
The touch panel is
The bonding structure of the touch panel and the flexible printed circuit board, characterized in that it further comprises a second protective layer formed on the outer portion of the insulating layer to be spaced apart from the unit bonding pad.

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