TW201606599A - Film touch sensor and method of preparing the same - Google Patents

Abstract

The present invention relates to a film touch sensor in which a separation layer is formed on a carrier substrate prior to the formation procedures of the touch sensor and is separated from the carrier substrate so that the separation layer can be used as a layer of covering wiring, and a method of preparing the film touch sensor. The film touch sensor according to the present invention comprises a separation layer; an electrode pattern layer formed on the separation layer and comprising a sensing electrode and a pad electrode formed at one end of the sensing electrode; an insulation layer formed on the electrode pattern layer; and a base film formed on the insulation layer, and a circuit board may connect with the pad electrode.

Description

Thin film touch sensor and preparation method thereof

The invention relates to a thin film touch sensor. In particular, the present invention relates to a thin film touch sensor prepared by forming a separation layer on a carrier substrate and then performing a forming process of the touch sensor; and the film type A method of preparing a touch sensor.

Various electronic devices adopt a touch input mode that is regarded as a next-generation input technology. In this regard, many research and developments have been actively pursued to provide a touch sensor that can be applied to various environments and accurately recognize input information by touch.

For example, since an electronic device having a touch display has been focused on an ultra-light and low-power thin film flexible display having improved portability as a next-generation display, touch sensing that can be applied to the display is required. Device.

The flexible display can be prepared on a flexible substrate that can be bent, folded or rolled without damaging its properties, and the flexible display can be a flexible LCD, a flexible OLED, an electronic paper, or the like. form.

In order to apply the touch input mode to such a flexible display, a touch sensor having good bendability, recovery, flexibility, and extensibility is required.

The flexible display can be prepared using a thin film touch sensor such as a wiring board including a wiring embedded in a transparent resin substrate.

The wiring board can be prepared by a program comprising the steps of: forming a metal wiring on a substrate; applying and drying a transparent resin solution for covering the metal wiring and forming a transparent resin substrate; and from the substrate The transparent resin substrate is peeled off.

An organic release material such as an anthraquinone resin and a fluororesin and an inorganic release material such as a film of a diamond-like carbon (DLC) and a film of zirconia are preliminarily formed on the surface of the substrate to make peeling effective.

However, the inorganic release materials are not capable of effectively stripping the metal wiring and the resin substrate from the surface of the substrate (on which the metal wiring and a portion of the resin substrate may remain), and the organic release material may be from the metal wiring and The surface of the resin substrate is exposed.

That is, it is difficult to induce complete peeling of the metal wiring from the substrate regardless of whether or not the release material is used.

Korean Patent No. 10-1191865 discloses a method for preparing a flexible substrate having a metal wiring embedded therein, the method comprising: forming a sacrificial layer, a metal wiring, and a polymer material in one And removing the sacrificial layer by a solvent or light to strip the metal wiring and the polymer material from the substrate.

However, it is difficult to carry out the removal of the sacrificial layer according to the above method in a large-sized product, and it is difficult to use various base films in the above method which cannot be carried out in a high temperature condition.

An object of the present invention is to provide a thin film touch sensor in which a separation layer is formed on a carrier substrate and separated from the carrier substrate before the forming process of the touch sensor, so that the separation layer is available. As a layer of covered wiring; and a method of preparing the thin film touch sensor.

Another object of the present invention is to provide a thin film touch sensor including an insulating layer formed on a pattern of a transparent conductive layer so that the insulating layer can be used. As a planarization layer; and a method of preparing the thin film touch sensor.

Still another object of the present invention is to provide a thin film touch sensor that is implemented on a carrier substrate to provide high definition and heat resistance (compared to a conventional touch that has been formed directly on a base film) A sensor is used, and various substrate films can be applied; and a method of preparing the film type touch sensor.

Another object of the present invention is to provide a thin film touch sensor in which a separation layer is formed on a carrier substrate, other component layers are formed on the separation layer, and a substrate film is adhered to the other component layers. The film type touch sensor is attached to a circuit board after being separated from the carrier substrate; and a method of preparing the film type touch sensor.

Another object of the present invention is to provide a thin film touch sensor that does not need to remove the separation layer after separating a separation layer from the carrier substrate; and a method of preparing the thin film touch sensor.

Another object of the present invention is to provide a thin film touch sensor further comprising an elastic control protective layer between the separation layer and the insulating layer due to the stress relieving ability between the separation layer and the insulating layer. A difference inhibits crack generation; and a method of preparing the thin film touch sensor.

The object of the present invention is not limited by the above objects, and those skilled in the art will understand the other unmentioned objects of the present invention from the following description.

According to an aspect of the present invention, a thin film touch sensor includes: a separation layer; an electrode pattern layer formed on the separation layer and including a sensing electrode and formed on the sensing electrode a pad electrode at one end; an insulating layer formed on the electrode pattern layer; and a base film formed on the insulating layer.

In addition, the thin film touch sensor may further include a protective layer formed between the separation layer and the electrode pattern layer.

The insulating layer may have a 300 MPa or less between the protective layer and the protective layer at 25 ° C A difference in modulus of elasticity.

Further, the insulating layer may have a difference in elastic modulus of 100 MPa or less between the protective layer and the protective layer at 25 °C.

In addition, the thin film touch sensor may further include a pad pattern layer formed on a bottom of the pad electrode.

In the present invention, the liner pattern layer may be at least one selected from the group consisting of a metal, a metal nanowire, a metal oxide, a carbon nanotube, a graphene, a conductive polymer, and a conductive ink. Formed.

The liner pattern layer may be composed of two or more conductive layers.

The insulating layer may be formed to cover the electrode pattern layer, and the insulating layer may be planarized on an opposite surface of a surface in contact with the electrode pattern layer.

The insulating layer may be formed of at least one selected from the group consisting of an organic insulating film and an inorganic insulating film.

The electrode pattern layer can be a transparent conductive layer.

The transparent conductive layer may be formed of at least one selected from the group consisting of a metal, a metal nanowire, a metal oxide, a carbon nanotube, graphene, a conductive polymer, and a conductive ink.

The electrode pattern layer may further include a bridge electrode.

The electrode pattern layer may be composed of two or more conductive layers.

The separation layer can be formed on a carrier substrate and then separated from the carrier substrate.

When the separation layer is separated from the carrier substrate, it may have a peel strength of 1 N/25 mm or less.

In addition, when the separation layer is separated from the carrier substrate, it may have a peel strength of 0.1 N/25 mm or less.

After the separation layer is peeled off from the carrier substrate, it may have a surface energy of from 30 mN/m to 70 mN/m.

The separation layer may have a surface energy difference of 10 mN/m or more between the separation layer and the carrier substrate.

The carrier substrate can be made of a glass.

The separation layer can be made of an organic polymer.

The organic polymer may comprise a polymer selected from the group consisting of polyimine, polyvinyl alcohol, polyglycolic acid, polyamine, polyethylene, polystyrene, polynorbornene, phenyl maleimide copolymer, poly couple Nitrobenzene, polyphenylene phthalamide, polyester, polymethyl methacrylate, polyarylate, cinnamate polymer, coumarin polymer, benzalkonium polymer, chalcone polymerization At least one of the group consisting of an aromatic acetylene polymer.

The separation layer may have a thickness of one of 10 nm to 1000 nm.

The separation layer may have a thickness of one of 50 nm to 500 nm.

Additionally, the thin film touch sensor can further include a circuit board electrically connected to the pad electrode.

The circuit board is connectable to the pad electrode through the separation layer.

The circuit board is connectable to the pad electrode through the pad pattern layer.

The base film may be any one selected from the group consisting of a polarizer, an isotropic film, a retardation film, and a protective film.

In addition, the thin film touch sensor may further include an adhesive layer formed between the insulating layer and the base film.

The adhesive layer may be formed of a pressure sensitive adhesive (PSA) or an adhesive.

According to another aspect of the present invention, a method for preparing the above-described thin film touch sensor includes the steps of: forming a separation layer on a carrier substrate; including a sensing electrode and a lining One electrode pattern layer of the pad electrode is formed on the separation layer; an insulating layer is formed on the electrode pattern layer; a base film is attached to the insulating layer; and by separating the separation layer from the carrier substrate The carrier substrate is removed.

In the present invention, an adhesive can be adhered to the base film and the insulating layer. The attachment of the base film is performed between.

Alternatively, the attachment of the base film can be carried out by adhering a pressure sensitive adhesive (PSA) between the base film and the insulating layer.

The method for preparing the thin film touch sensor may further include the steps of: forming a protective layer on the separation layer after forming the separation layer; and removing a portion of the protective layer (which corresponds to Wherein a region of the pad electrode is formed such that the separation layer is exposed. Thereby, the formation of the electrode pattern layer can be performed on the protective layer and the exposed separation layer.

In addition, the method for preparing the thin film touch sensor may further include the step of forming a protective layer on the separation layer after forming the separation layer, and the formation of the protective layer may be implemented such that it is to be formed A region of the separation layer of the pad electrode is partially exposed. Thereby, the formation of the electrode pattern layer can be performed on the protective layer and the exposed separation layer.

Furthermore, the method for preparing the thin film touch sensor may further include the step of pre-forming a pad pattern layer in a region of the pad electrode to be formed before forming the pad electrode.

The removal of the carrier substrate can be carried out by separating the separation layer from the carrier substrate by lift-off or lift-off.

The removal of the carrier substrate can be carried out by using a force of 1 N/25 mm or less to separate the separation layer from the carrier substrate.

Additionally, the method for fabricating the thin film touch sensor can further include the step of attaching a circuit board to the pad electrode after removing the carrier substrate.

Moreover, the method for preparing the thin film touch sensor may further include the step of attaching a circuit board to the pad pattern layer after removing the carrier substrate.

The thin film type touch sensor and the preparation method thereof according to the present invention have the following effects:

First, the separation layer can be used as a layer of overlay wiring because it is formed on a carrier substrate and separated from the carrier substrate before the formation process of the touch sensor, thereby improving the efficiency of the program and productivity.

Second, the insulating layer formed on the pattern of a transparent conductive layer can be used as a planarization layer, thereby improving the efficiency of a program for preparing a touch sensor.

Third, the procedure for implementing the touch sensor on a carrier substrate provides high definition and heat resistance and can be applied to various substrate films.

Fourth, the liner pattern layer (which is formed as a single layer on the separation layer or a plurality of layers composed of a metal or a metal oxide) can effectively reduce contact resistance with a circuit board. This improves the stability of the program.

Fifth, the liner pattern layer can be attached to a circuit board without removing the separation layer formed on the carrier substrate, thereby increasing the efficiency of the program.

Sixth, after the separation layer is separated from the carrier substrate, there is no need to remove the separation layer, thereby achieving a simple procedure and overcoming the problems that can occur in one of the touch sensor removal procedures.

Seventh, the elastic control protective layer (which is further formed between the separation layer and the insulating layer) can suppress crack generation due to a difference in stress-relieving ability between the separation layer and the insulating layer.

10‧‧‧ Carrier substrate

20‧‧‧Separation layer

30‧‧‧Protective layer

40‧‧‧ liner pattern layer

41‧‧‧First pad pattern layer

42‧‧‧Second pad pattern layer

50‧‧‧electrode pattern layer

51‧‧‧First electrode layer

52‧‧‧Second electrode layer

60‧‧‧Photosensitive photoresist

70‧‧‧Insulation

80‧‧‧Adhesive layer

100‧‧‧base film

110‧‧‧Circuit board

PE‧‧‧ gasket electrode

SE‧‧‧Sensing electrode

1 to 4 are cross-sectional views showing respective structures of a film type touch sensor according to an embodiment of the present invention.

5a-5k schematically illustrate a procedure for preparing a thin film touch sensor in accordance with an embodiment of the present invention.

Hereinafter, a preferred embodiment of a thin film type touch sensor and a method of fabricating the same according to the present invention will be described in detail below.

The features and advantages of the thin film touch sensor and the method of fabricating the same according to the present invention will be apparent from the following detailed description of the embodiments.

1 to 4 are cross-sectional views showing respective structures of a film type touch sensor according to an embodiment of the present invention.

The present invention provides a thin film touch sensor in which a separation layer is formed on a carrier substrate and separated from the carrier substrate before the formation process of the touch sensor, so that the separation layer can be used as One layer covers the wiring, thereby ensuring high definition and heat resistance (unlike one of the conventional touch sensors that have been formed directly on a base film), and allows various substrate films to be applied.

The present invention will form a liner pattern layer on the separation layer as a single layer or a plurality of layers composed of a metal or a metal oxide to effectively reduce contact resistance with one of the circuit boards. Improve the stability of the program.

As shown in FIG. 1 , the thin film touch sensor of the present invention may include: a separation layer; an electrode pattern layer formed on the separation layer and including a sensing electrode and formed on the sensing layer a pad electrode at one end of the electrode; an insulating layer formed on the electrode pattern layer; and a base film formed on the insulating layer.

The separation layer may be composed of an organic polymer (for example selected from the group consisting of polyimine, polyvinyl alcohol, polyglycolic acid, polyamine, polyethylene, polystyrene, polynorbornene, phenyl malayan) Amine copolymer, polyazobenzene, polyphenylene phthalamide, polyester, polymethyl methacrylate, polyarylate, cinnamate polymer, coumarin polymer, benzalkonium amide polymerization It is made of at least one of a group consisting of a substance, a chalcone polymer and an aromatic acetylene polymer.

The separation layer 20 is formed on a carrier substrate 10, and then, after the electrode pattern layer is formed on the separation layer 20, the separation layer 20 is separated from the carrier substrate 10.

When the separation layer is separated from the carrier substrate, the separation layer preferably has a peel strength of 1 N/25 mm or less, more preferably 0.1 N/25 mm or less. That is, preferably, the separation layer is maintained by a physical force that can be applied during the separation of the separation layer 20 from the carrier substrate 10. In 1N/25mm, in particular, one material of 0.1N/25mm is formed.

If the peeling strength of the separation layer 20 exceeds 1 N/25 mm, it is difficult to clearly separate the separation layer from the carrier substrate, so that the separation layer 20 can be left on the carrier substrate. Further, cracks may be generated in at least one of the separation layer 20, the protective layer 30, the electrode pattern layer 50, and the insulating layer 70.

Specifically, the peeling strength of the separation layer 20 is preferably 0.1 N/25 mm or less because it allows the film to be curled after being separated from the carrier substrate. Curling can degrade the efficiency of the adhesion and cutting process, but it does not affect the function of the thin film touch sensor itself. Therefore, curling can be advantageously minimized.

The separation layer preferably has a thickness of from 10 nm to 1000 nm, more preferably from 50 nm to 500 nm. If the thickness of the separation layer is less than 10 nm, the separation layer may be unevenly formed to induce formation of an uneven electrode pattern, and the peel strength of the separation layer may be locally increased to cause damage or may not be separated from the carrier substrate after the separation layer is separated from the carrier substrate Control the curling. If the thickness of the separation layer is more than 1000 nm, the peel strength of the separation layer can be no longer lowered, and the flexibility of the film can be deteriorated.

After the separation layer is peeled off from the carrier substrate, the separation layer preferably has a surface energy of from 30 mN/m to 70 mN/m. Further, the separation layer preferably has a surface energy difference of 10 mN/m or more between it and the carrier substrate. The separation layer should maintain a stable adhesion to the carrier substrate until it is separated from the carrier substrate, and should then be easily separated without damaging the thin film touch sensor or creating curling. When the surface of the separation layer can satisfy the range of 30 mN/m to 70 mN/m, the peel strength can be controlled to ensure good adhesion between the separation layer and the adjacent protective layer or electrode pattern layer to improve the efficiency of the process. In addition, when the separation layer satisfies a surface energy difference of 10 mN/m or more between the carrier substrate and the carrier substrate, the separation layer can be easily separated from the carrier substrate to prevent damage to the thin film type touch sensor or in the film type. Cracks are formed in the layers of the touch sensor.

The separation layer 20 serves as a layer covering one of the electrode pattern layers 50 formed thereon or serves as a layer The electrode pattern layer 50 is protected from external contact with one layer after the separation layer 20 is separated from the carrier substrate.

At least one protective layer 30 may be further formed on the separation layer 20. Since only the separation layer 20 is difficult to achieve complete protection of the electrode pattern from external contact or influence, at least one protective layer 30 for protection purposes can be formed.

The protective layer 30 may include at least one of an organic insulating film and an inorganic insulating film and may be formed by coating and curing or deposition.

The protective layer may be formed such that a portion of the protective layer corresponding to a region in which the pad electrode is to be formed is removed by patterning or a region where the pad electrode is to be formed is excluded. Preferably, the protective layer can be formed such that the separation layer is exposed. This allows a good connection between the pad electrode and the board when a board is attached.

A pad pattern layer 40 may be formed on the bottom of the pad electrode. The pad pattern layer serves to reduce the contact resistance when the pad electrode is connected to the circuit board. If the contact resistance is sufficiently low when the pad electrode is connected to the board, the pad pattern layer can be omitted.

The liner pattern layer 40 may be formed of at least one selected from the group consisting of a metal, a metal nanowire, a metal oxide, a carbon nanotube, graphene, a conductive polymer, and a conductive ink.

Examples of the metal may include an alloy of gold (Au), silver (Ag), copper (Cu), molybdenum (Mo), aluminum, palladium, rhodium, and Ag-Pd-Cu (APC).

Examples of the metal nanowire may include a silver nanowire, a copper nanowire, a zirconium nanowire, and a golden nanowire.

Examples of the metal oxide may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), fluorine-doped tin oxide (FTO). ), zinc oxide (ZnO), indium tin oxide-Ag-indium tin oxide (ITO-Ag-ITO), indium zinc oxide-Ag-indium zinc oxide (IZO-Ag-IZO), indium zinc sulfide-Ag-oxidation Indium zinc tin oxide (IZTO-Ag-IZTO) and zinc oxide-Ag-alumina zinc oxide (AZO-Ag-AZO).

In addition, the pad pattern layer 40 may be formed of a carbon material such as a carbon nanotube (CNT) and graphene.

Examples of the conductive polymer may include polypyrrole, polythiophene, polyacetylene, PEDOT, and polyaniline.

The conductive ink can be a mixture of a metal powder and a curable polymer binder.

In order to reduce the resistance and the contact resistance with a circuit board, the pad pattern layer 40 may be composed of two or more conductive layers (for example, a first pad pattern layer 41 and a second pad pattern layer 42), such as Shown in Figures 2a and 2b.

Specifically, the liner pattern layer 40 may have a structure in which a metal oxide is laminated and a metal is laminated on the metal oxide; wherein a metal is laminated and a metal oxide is laminated thereon a structure on a metal; wherein a metal is laminated, a metal oxide is laminated on the metal, and a metal is further laminated on the metal oxide; and a metal oxide is laminated thereon, A metal is laminated to the metal oxide and a metal oxide is further laminated to one of the structures on the metal.

The electrode pattern layer 50 may be formed on the separation layer 20 or the protective layer 30. The electrode pattern layer 50 may include: a sensing electrode (SE) that senses a touch operation; and a pad electrode (PE) formed at one end of the sensing electrode (SE). The sensing electrode (SE) may include one of an electrode for sensing a touch operation and a wiring pattern connected to the electrode. The pad electrode (PE) can be electrically connected to a circuit board.

The electrode pattern layer 50 can be a transparent conductive layer and can be selected from the group consisting of a metal, a metal nanowire, a metal oxide, a carbon nanotube, a graphene, a conductive polymer, and a conductive ink. At least one is formed.

Examples of the metal may include an alloy of gold (Au), silver (Ag), copper (Cu), molybdenum (Mo), aluminum, palladium, rhodium, and Ag-Pd-Cu (APC).

Examples of the metal nanowire may include a silver nanowire, a copper nanowire, a zirconium nanowire, and Jinnai line.

Examples of the metal oxide may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), fluorine-doped tin oxide (FTO). ), zinc oxide (ZnO), indium tin oxide-Ag-indium tin oxide (ITO-Ag-ITO), indium zinc oxide-Ag-indium zinc oxide (IZO-Ag-IZO), indium zinc sulfide-Ag-oxidation Indium zinc tin oxide (IZTO-Ag-IZTO) and zinc oxide-Ag-alumina zinc oxide (AZO-Ag-AZO).

In addition, the electrode pattern layer 50 may be formed of a carbon material such as a carbon nanotube (CNT) and graphene.

Examples of the conductive polymer may include polypyrrole, polythiophene, polyacetylene, PEDOT, and polyaniline.

The conductive ink can be a mixture of a metal powder and a curable polymer binder.

To reduce the electrical resistance, the electrode pattern layer 50 may be composed of two or more conductive layers (eg, a first electrode layer 51 and a second electrode layer 52), as shown in Figure 2a.

For example, the electrode pattern layer 50 may be formed of a single layer of ITO, AgNW (silver nanowire) or a metal mesh, or a first layer 51 including a transparent metal oxide (such as ITO) and formed on the ITO electrode layer. One or two or more layers of the second layer 52 of one of the metals or AgNW are configured to continuously reduce the electrical resistance.

In addition, the electrode pattern layer 50 may include at least one layer of a metal or a metal oxide to improve conductivity. More specifically, the electrode pattern layer may be obtained by forming a transparent conductive layer of a metal or a metal oxide on the separation layer or the protective layer and further laminating a transparent conductive layer to form an electrode pattern; The electrode pattern layer is obtained by laminating at least one transparent conductive layer on the separation layer or the protective layer and further forming a transparent conductive layer of one metal or one metal oxide to form an electrode pattern. For example, the electrode pattern may have a structure in which a pattern layer of a metal or a metal oxide is further formed between the separation layer and the electrode pattern layer; wherein a pattern of one metal or one metal oxide is layered into one Forming a structure between the electrode pattern layer and the insulating layer; or forming a metal or a metal oxide pattern layer further formed between the protective layer and the electrode pattern layer and further forming a transparent conductive At least one electrode pattern layer of material.

A suitable laminate structure of the electrode pattern layer 50 may, for example, comprise: a structure in which a metal oxide layer is laminated and a silver nanowire layer is laminated on the metal oxide layer; wherein a metal oxide is laminated a layer of a metal layer laminated on the metal oxide layer; wherein a metal oxide layer is laminated and a metal mesh electrode layer is laminated on the metal oxide layer; Pressing a silver nanowire layer and laminating a metal oxide layer on one of the silver nanowire layers; laminating a metal layer and laminating a metal oxide layer on the metal layer a structure in which a metal mesh electrode layer is laminated and a metal oxide layer is laminated on the metal mesh electrode layer; wherein a metal oxide layer is laminated, and a silver nanowire layer is laminated thereon a metal oxide layer, and a metal layer is laminated on one of the silver nanowire layers; wherein a silver nanowire layer is laminated, and a metal oxide layer is laminated on the silver nanowire layer And a metal layer is laminated on one of the structures on the metal oxide layer.

The electrode laminate structures can be modified according to the signal processing and resistance of the touch sensor, and thus the present invention is not limited thereto.

The electrode pattern layer can be configured to have an insulating layer between the first electrode pattern layer and the second electrode pattern layer. Additionally, the insulating layer can be patterned to form contact holes such that the second conductive layer can act as a bridge electrode.

Further, the structure of the electrode pattern layer is described in accordance with the touch sensor mode.

The electrode pattern layer preferably has a pattern structure for use in a capacitive mode such as a mutual capacitance mode and a self capacitance mode.

The mutual capacitance mode may have a grid electrode structure of one horizontal axis and one vertical axis. The intersection between the horizontal axis and the electrodes on the vertical axis may have a bridge electrode. Alternatively, the horizontal axis and each of the electrode pattern layers on the vertical axis may be formed and each of them may be electrically separated from each other.

The self-capacitance mode may have an electrode layer structure that uses one of the electrodes in each position to recognize a change in capacitance.

The electrode pattern layer 50 can have a photosensitive photoresist 60 as shown in Figure 2b. The electrode pattern layer 50 may be formed by photolithography, and the photosensitive photoresist may be retained or removed after the electrode pattern layer is formed according to the type of the electrode pattern layer. A retained photosensitive photoresist can be used to protect the electrode pattern layer.

The insulating layer 70 is formed on the electrode pattern layer 50 to suppress corrosion of the electrode pattern and protect the surface of the electrode pattern. The insulating layer 70 fills one of the gaps in the electrode or wiring, and is preferably formed to have a certain thickness. That is, it is preferable that the insulating layer is planarized on the opposite surface of the surface in contact with the electrode pattern layer 50, so that the uneven portion of the electrode is not exposed.

The difference in modulus of elasticity between the insulating layer and the protective layer at 25 ° C is preferably 300 MPa or less, more preferably 100 MPa or less, so that cracks are suppressed by a difference in stress-relieving ability between the layers. produce. If the difference in elastic modulus between the insulating layer and the protective layer at 25 ° C exceeds 300 MPa, cracks are generated due to an imbalance in the stress-relieving ability between the insulating layer and the protective layer.

This elastic modulus difference is measured under conditions of 25 ° C which fall within the environment in which a user is used.

The insulating layer may be formed of any organic insulating material capable of causing one of the elastic modulus differences between the protective layer and the protective layer to be 300 MPa or less at 25 ° C. For example, it is preferred to use a thermally curable or UV curable organic polymer.

The insulating layer may be formed of at least one selected from the group consisting of an epoxy resin compound, an acrylic compound, and a melamine compound.

The insulating layer 70 itself can serve as an adhesive layer composed of a pressure sensitive adhesive (PSA) or an adhesive. The insulating layer may comprise at least one selected from the group consisting of polyesters, polyethers, polyurethanes, epoxies, enamels, and acrylates. When the insulating layer 70 acts as an adhesive layer, the base film 100 can be directly attached to the insulating layer 70, as shown in FIGS. 1 and 2.

As shown in FIG. 3, an additional adhesive layer 80 for attachment may also be formed between the insulating layer 70 and the base film 100. The adhesive layer 80 can be formed of a pressure sensitive adhesive (PSA) or an adhesive. For this purpose, both heat curable adhesives and UV curable adhesives can be used. The adhesive layer may be preformed on one surface of the base film prior to attachment, wherein a non-carrier film (NCF) type adhesive or a pressure sensitive adhesive (PSA) film may be used. Alternatively, the adhesive layer may be formed by coating on the insulating layer, and then the base film may be attached to the adhesive layer. In this case, a light-transmitting resin (OCR) type liquid adhesive is applied and then the base film to be attached is placed on the OCR type liquid adhesive, followed by curing. The adhesive or pressure sensitive adhesive (PSA) for attachment of the base film 100 is preferably a polyester, a polyether, a polyurethane, an epoxy resin, a enamel or an acrylic adhesive.

In the present invention, the base film 100 can be a transparent film or a polarizer.

If the transparent film has good transparency, mechanical strength and thermal stability, it is not limited. Specific examples of the transparent film may include: a thermoplastic resin such as a polyester resin such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, and polybutylene terephthalate Ester; cellulose resin, such as diethyl phthalocyanine and triethyl hydrazine cellulose; polycarbonate resin; acrylate resin, such as polymethyl methacrylate and polyethyl methacrylate; styrene resin, such as polyphenylene Ethylene and acrylonitrile-styrene copolymer; polyolefin resin such as polyethylene, polypropylene, polyolefin having a cyclic or norbornene structure, and ethylene-propylene copolymer; vinyl chloride resin; guanamine resin, such as Nylon and aromatic polyamine; quinone imine resin; polyether oxime resin; oxime resin; polyetheretherketone resin; polyphenylene sulfide resin; vinyl alcohol resin; dichloroethylene vinyl resin; vinyl butyral resin; Allyl resin; polyacetal resin; and epoxy resin. Further, a film composed of a blend of one of thermoplastic resins may be used. Further, heat curable or UV curable resins such as (meth) acrylate, urethane, urethane acrylate, epoxy resin and enamel resin may be used. The transparent film can have a suitable thickness. For example, considering the strength and the processability of the treatment or the properties of the thin layer, the thickness of the transparent film may be from 1 μm to 500 μm, preferably. Ground, from 1 μm to 300 μm, more preferably, from 5 μm to 200 μm.

The transparent film may contain at least one suitable additive. Examples of the additive may include a UV absorber, an antioxidant, a lubricant, a plasticizer, a mold release agent, a color preventive agent, a flame retardant, a nucleating agent, an antistatic agent, and a Pigments and a colorant. The transparent film may include various functional layers including a hard coat layer, an anti-reflection layer, and a gas barrier layer, but the invention is not limited thereto. That is, other functional layers may be included depending on the intended use.

The transparent film can be surface treated if desired. For example, the surface treatment can be carried out by a drying method such as plasma, corona and primer treatment or by a chemical method such as treatment with a base containing saponification.

Alternatively, the transparent film can be an isotropic film, a retardation film or a protective film.

In the case of an isotropic film, it is preferable to satisfy 40 nm or less, preferably, an in-plane retardation (Ro) of 15 nm or less and -90 nm to +75 nm, preferably -80 nm to +60 nm. Specifically, one of -70 nm to +45 nm thickness retardation amount (Rth), the in-plane retardation amount (Ro), and the thickness retardation amount (Rth) are represented by the following equation.

Ro=[(nx-ny)×d]

Rth=[(nx+ny)/2-nz]×d

Wherein nx and ny are respectively a primary refractive index of a film plane, a refractive index of a thickness direction of the nz-based film, and a thickness of one of the d-type films.

The retardation film can be prepared by uniaxially extending or biaxially extending a polymer film, coating a polymer, or coating a liquid crystal, and is generally used to improve or control optical properties, such as viewing angle compensation, Improved color sensitivity, light leakage prevention or color control of a display.

The retardation film may comprise half-wave (1/2) or quarter-wave (1/4), a positive C-plate, a negative C-plate, a positive A-plate, a negative A-plate, and a biaxial board.

The protective film may be: a polymer resin film comprising a pressure sensitive adhesive (PSA) layer on at least one surface thereof; or a self-adhesive film such as polypropylene. The protective film can be used to protect the touch sensor and improve processability.

The polarizer can be any known polarizer used in a display panel.

Specifically, by laminating a protective layer on at least one surface of a polarizer obtained by dyeing a stretched polyvinyl alcohol resin film using iodine or a dichroic pigment, The liquid crystal is oriented to provide a polarizer function, or a polarizer is prepared by applying a certain resin (such as polyvinyl alcohol) to a transparent film, followed by stretching and dyeing, but the invention is not limited thereto.

As shown in FIG. 4, the thin film touch sensor can be electrically connected to a circuit board. The circuit board can be a flexible printed circuit board (FPCB) and is used to electrically connect the thin film touch sensor of the present invention to a touch switch circuit. A conductive adhesive can be used to attach the thin film touch sensor to the circuit board.

The circuit board 110 has an electrode formed at one end thereof and corresponding to one of the pad electrodes (PE), and is electrically connected to the pad electrode (PE) through a conductive adhesive. To reduce the contact resistance between the board and the pad electrode (PE), the board can also be electrically connected to the pad electrode (PE) through a pad pattern layer 40. For example, the circuit board can be connected to the thin film touch sensor by attaching it to the pad pattern layer through a separate layer, as shown in FIG.

The connection of the circuit board and the pad electrode can be implemented through the pad pattern layer to reduce the contact resistance between the circuit board and the pad electrode, and this can be selectively applied according to the production procedure and product specifications.

Additionally, the circuit board can be connected to a pad electrode or pad pattern layer that is exposed by removing a portion of the separation layer. Partial removal of the separation layer 20 can be performed by a wet etching procedure using an etching solution that can vary depending on the material of the separation layer 20.

For example, if the separation layer 20 is composed of a polymer such as polyimine, polyvinyl alcohol, and polyglycolic acid, an alkaline solution of KOH, TMAH or amine can be used, and if the separation layer From a polymer such as polyester, cinnamate, coumarin, chalcone and aromatic acetylene, an acidic solution of one of phosphoric acid, acetic acid or nitric acid can be used.

A method of fabricating the above-described thin film type touch sensor according to the present invention will be described hereinafter with reference to FIGS. 5a to 5k.

5a-5k schematically illustrate a procedure for preparing a thin film touch sensor in accordance with an embodiment of the present invention.

As shown in Figure 5a, a carrier substrate is coated with an organic polymer film to form a separation layer 20.

The formation of the separation layer can be carried out by one of the conventional coating methods known in the art.

For example, it may involve spin coating, die coating, spray coating, roll coating, screen coating, slit coating, dip coating, gravure coating, and the like.

The carrier substrate 10 may be a glass, but is not limited thereto. That is, if other types of substrates can withstand the formation of a program temperature of the electrodes and maintain a flat, non-deformable heat-resistant material at a high temperature, the substrates can be used as the carrier substrate 10.

After coating, the separation layer 20 is subjected to curing by heat curing or UV curing. These thermal curing and UV curing can be carried out singly or in combination.

As shown in Figure 5b, an organic insulating material is applied to the separation layer to form a protective layer 30.

A portion of the protective layer 30 is subjected to patterning for removal thereof to provide a region to form a liner pattern layer 40, as shown in Figure 5c.

The protective layer 30 may be removed by patterning after forming the protective layer 30 to form a pad pattern layer for connecting a circuit, or may be coated with an organic insulating material (except for a region in which the pad pattern layer is to be formed) The protective layer 30 is formed. A liner pattern layer for connecting a circuit can be formed in a portion in which the protective layer is not formed. In an embodiment of the invention, it is described that the removal of the protective layer 30 is performed by patterning.

Next, as shown in FIG. 5d, a liner is formed by depositing a metal on the remaining protective layer and the region where the protective layer is removed and allowing the metal layer to remain only in the region where the protective layer is subjected to patterning. Pattern layer 40.

The liner pattern layer 40 may be formed of at least one selected from the group consisting of a metal, a metal nanowire, a metal oxide, a carbon nanotube, a graphene, a conductive polymer, and a conductive ink, and It may consist of a single conductive layer or two or more conductive layers in view of the resistance. For a single layer, the liner pattern layer can be formed from at least one of a metal and a metal oxide. For the two layers, one of the first liner pattern layers of copper and one of the second liner pattern layers of one of the materials (such as gold) having a conductivity better than that of the electrode material is preferably formed. In addition, the pad pattern layer may be omitted when a pad electrode is formed of a material having a lower resistance to provide a sufficiently low contact resistance to be connected to a circuit. In an embodiment of the invention, it is described that the liner pattern layer has a laminate structure of two layers.

Next, an electrode pattern layer is formed on the protective layer and the liner pattern layer.

As shown in FIG. 5e, a first electrode layer 51 is formed as one of the silver nanowires (AgNW) transparent conductive layer, and one of the metal second electrode layers 52 is formed on the first electrode layer 51. Next, a photosensitive photoresist 60 is formed on the metal conductive layer as shown in Figure 5f. Subsequently, one photolithography process for selective patterning is implemented to form an electrode pattern layer 50, as shown in Figure 5g.

Can be by a sputtering method (such as chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma enhanced chemical vapor deposition (PECVD)), a printing method (such as screen printing, gravure printing, A transparent conductive layer is formed by reverse lithography, inkjet printing, or a wet or dry plating method. In particular, sputtering may be performed on a mask disposed on a substrate to form an electrode pattern layer having a desired electrode pattern shape. After the conductive layer is formed by the above method, the electrode pattern layer can be formed by photolithography.

A negative photosensitive resist or a positive photosensitive resist can be used as the photosensitive photoresist 60. This photoresist can be left on the electrode pattern layer 50 if necessary. Alternative Ground, this photoresist can be removed. In one embodiment of the invention, it is described that a negative photosensitive resist is used and left on an electrode pattern after patterning.

Further, the formation of an additional electrode pattern can be performed according to the electrode pattern structure.

Thereafter, an insulating layer 70 is formed to cover the electrode pattern layer 50, as shown in Figure 5h. The insulating layer 70 may have the same thickness as the electrode or may be thicker than the electrode such that the insulating layer has a planarized upper surface. That is, the insulating layer is preferably formed of an insulating material having a suitable viscoelasticity such that the uneven portion of the electrode is not transferred.

Specifically, the formation of the insulating layer can be performed by applying a liquid material of one of the insulating layers to the electrode pattern layer, followed by thermal curing or UV curing.

Coating for forming an insulating layer can be carried out by a conventional coating method known in the art.

For example, it may involve spin coating, die coating, spray coating, roll coating, screen coating, slit coating, dip coating, gravure coating, and the like.

Next, an adhesive layer 80 is formed on the insulating layer to attach a base film 100, as shown in Figure 5i. The adhesive layer 80 is preliminarily formed on one surface of the base film before attaching the base film to the insulating layer, and a non-carrier film (NCF) type adhesive or a pressure sensitive adhesive (PSA) film may be used. Alternatively, the adhesive layer 80 may be formed by coating on the insulating layer 70, and then the base film 100 may be attached to the adhesive layer 80. In this case, a light-transmitting resin (OCR) type liquid adhesive is applied and then the base film to be attached is placed on the OCR type liquid adhesive, followed by curing.

Next, as shown in FIG. 5j, the separation layer 20 on which the electrodes are formed is separated from the carrier substrate 10.

In the present invention, the separation of the separation layer 20 from the carrier substrate is carried out by lift-off.

Examples of the stripping method may include, but are not limited to, lift-off or peeling.

For peeling, one force of 1 N/25 mm or less, preferably 0.1 N/25 mm or less may be applied, and the force may be varied depending on the peel strength of the separation layer. If the peel strength exceeds 1N/25mm will damage the thin film touch sensor during the peeling from the carrier substrate and apply an excessive force to the thin film touch sensor, thereby causing the thin film touch sensor to be deformed and unable to Act as a device.

Thereafter, a thin film touch sensor is attached to a circuit board 110, wherein a conductive adhesive is available for attachment to the circuit board 110.

Conductive adhesive means one of conductive adhesives (such as gold, silver, copper, nickel, carbon, aluminum) dispersed in one of epoxy, hydrazine, urethane, acrylic or polyimide resin. And gold plating) is one of the adhesives.

When the circuit board 110 is attached after being separated from the carrier substrate 10, the attachment is preferably performed using a conductive adhesive in the direction of the separation layer 20. The circuit board 110 may be attached to the pad electrode (PE) through the separation layer 20, or may pass through the pad pattern layer 40 formed on the bottom of the pad electrode (PE) via the separation layer 20 and the pad electrode ( PE) attached.

As shown in Figure 5k, the circuit board 110 is attached to the pad electrode (PE) through the pad pattern layer 40. That is, in one embodiment of the invention, it is described that the circuit board is attached to the pad pattern layer by a conductive adhesive via the separation layer, thereby allowing the connection of the circuit board and the pad electrode (PE).

A thin film touch sensor prepared by the present invention can be used such that its base film is disposed in a visible side attached to one of the display panels or a substrate film thereof is disposed in the side of the display panel. In addition, the separation layer of the thin film touch sensor can be attached to other optical films, such as a polarizer and a transparent film.

Therefore, the thin film type touch sensor and the preparation method thereof according to the present invention can provide high definition and heat resistance (which is a conventional touch formed on a base film) because it is implemented on a carrier substrate. It is not possible in the case of a sensor, and various substrate films can be applied. That is, a base film having weak heat resistance can be used because it is attached after forming an electrode.

In addition, a circuit board can be attached and connected through a separation layer formed on the carrier substrate. Separation from the separation layer without removing or removing the separation layer, thereby increasing the efficiency of the procedure.

In addition, the peel strength and surface energy of the separation layer can be parameterized during the procedure to increase the efficiency of the process and prevent cracking.

Although a particular embodiment of the invention has been shown and described, it will be understood by those skilled in the art Various changes and modifications are made in the circumstances.

Accordingly, the scope of the invention is defined by the scope of the appended claims and their equivalents.

20‧‧‧Separation layer

30‧‧‧Protective layer

40‧‧‧ liner pattern layer

50‧‧‧electrode pattern layer

70‧‧‧Insulation

100‧‧‧base film

PE‧‧‧ gasket electrode

SE‧‧‧Sensing electrode

Claims (39)

A thin film touch sensor includes: a separation layer; an electrode pattern layer formed on the separation layer, and comprising a sensing electrode and a lining formed at one end of the sensing electrode a pad electrode; an insulating layer formed on the electrode pattern layer; and a base film formed on the insulating layer. The thin film touch sensor of claim 1, further comprising a protective layer formed between the separation layer and the electrode pattern layer. The thin film type touch sensor of claim 2, wherein the insulating layer has a difference in elastic modulus of 300 MPa or less between the protective layer and the protective layer at 25 ° C. The thin film type touch sensor of claim 2, wherein the insulating layer has a difference in elastic modulus of 100 MPa or less between the protective layer and the protective layer at 25 ° C. The thin film touch sensor of claim 1, further comprising a pad pattern layer formed on a bottom of the pad electrode. The thin film touch sensor of claim 5, wherein the liner pattern layer is selected from the group consisting of a metal, a metal nanowire, a metal oxide, a carbon nanotube, a graphene, a conductive polymer, and At least one of the group consisting of a conductive ink is formed. The thin film touch sensor of claim 5, wherein the liner pattern layer is composed of two or more conductive layers. The thin film touch sensor of claim 1, wherein the insulating layer is formed to cover the electrode pattern layer and planarize the insulating layer on an opposite surface of a surface in contact with the electrode pattern layer. The thin film touch sensor of claim 1, wherein the insulating layer is formed of at least one selected from the group consisting of an organic insulating film and an inorganic insulating film. The thin film touch sensor of claim 1, wherein the electrode pattern layer is a transparent conductive layer. The thin film touch sensor of claim 10, wherein the transparent conductive layer is selected from the group consisting of a metal, a metal nanowire, a metal oxide, a carbon nanotube, a graphene, a conductive polymer, and a At least one of the group consisting of conductive inks is formed. The thin film touch sensor of claim 10, wherein the electrode pattern layer further comprises a bridge electrode. The thin film touch sensor of claim 1 or 10, wherein the electrode pattern layer is composed of two or more conductive layers. The thin film touch sensor of claim 1, wherein the separation layer is formed on a carrier substrate and then separated from the carrier substrate. The thin film touch sensor of claim 14, wherein the separation layer has a peel strength of 1 N/25 mm or less when the separation layer is separated from the carrier substrate. The thin film touch sensor of claim 14, wherein the separation layer has a peel strength of 0.1 N/25 mm or less when the separation layer is separated from the carrier substrate. The thin film type touch sensor of claim 14, wherein the separation layer has a surface energy of from 30 mN/m to 70 mN/m after the separation layer is peeled off from the carrier substrate. The thin film touch sensor of claim 17, wherein the separation layer has a surface energy difference of 10 mN/m or more between the separation layer and the carrier substrate. The thin film touch sensor of claim 14, wherein the carrier substrate is made of a glass. The thin film touch sensor of claim 1 or 14, wherein the separation layer is made of an organic polymer. The thin film touch sensor of claim 20, wherein the organic polymer comprises a polymer selected from the group consisting of polyimine, polyvinyl alcohol, polyamic acid, polyamine, polyethylene, polyphenylene Alkene, polynorbornene, phenyl maleimide copolymer, polyazobenzene, polyphenylene phthalamide, polyester, polymethyl methacrylate, polyarylate, cinnamate polymer At least one of the group consisting of a coumarin polymer, a benzalkonium polymer, a chalcone polymer, and an aromatic acetylene polymer. The thin film touch sensor of claim 1 or 14, wherein the separation layer has a thickness of one of 10 nm to 1000 nm. The thin film touch sensor of claim 1 or 14, wherein the separation layer has a thickness of one of 50 nm to 500 nm. The thin film touch sensor of claim 1, further comprising a circuit board electrically connected to the pad electrode. The thin film touch sensor of claim 24, wherein the circuit board is connected to the pad electrode through the separation layer. The thin film touch sensor of claim 24, wherein the circuit board is connected to the pad electrode through the pad pattern layer. The film type touch sensor of claim 1, wherein the base film is selected from the group consisting of a polarizer, an isotropic film, a retardation film and a protective film. The thin film touch sensor of claim 1, further comprising an adhesive layer formed between the insulating layer and the base film. The thin film touch sensor of claim 28, wherein the adhesive layer is formed of a pressure sensitive adhesive (PSA) or an adhesive. A method for preparing a thin film touch sensor, comprising the steps of: forming a separation layer on a carrier substrate; forming an electrode pattern layer including a sensing electrode and a pad electrode Separating layers; forming an insulating layer on the electrode pattern layer; Attaching a base film to the insulating layer; and removing the carrier substrate by separating the separation layer from the carrier substrate. A method for preparing a thin film touch sensor according to claim 30, wherein the attachment of the base film is performed by adhering an adhesive between the base film and the insulating layer. A method for preparing a thin film touch sensor according to claim 30, wherein the attachment of the base film is performed by adhering a pressure sensitive adhesive (PSA) between the base film and the insulating layer. Pick up. The method for preparing a thin film touch sensor according to claim 30, further comprising the steps of: forming a protective layer on the separation layer after forming the separation layer; and removing the corresponding one formed therein A portion of the protective layer in one of the pad electrodes is such that the separation layer is exposed, wherein the formation of the electrode pattern layer is performed on the protective layer and the exposed separation layer. The method for preparing a thin film touch sensor of claim 30, further comprising the step of forming a protective layer on the separation layer after forming the separation layer, wherein the formation of the protective layer is implemented such that A region of the separation layer for forming the pad electrode is partially exposed, and the formation of the electrode pattern layer is performed on the protective layer and the exposed separation layer. The method for preparing a thin film touch sensor according to any one of claims 30, 33 and 34, further comprising pre-forming a liner pattern layer for forming the liner before forming the spacer electrode The step in one of the pad electrodes. A method for preparing a thin film touch sensor according to claim 30, wherein the removing of the carrier substrate is performed by separating the separation layer from the carrier substrate by lift-off or peeling. A method for preparing a thin film touch sensor according to claim 30 or 36, wherein the carrier substrate is implemented by separating the separation layer from the carrier substrate by using a force of 1 N/25 mm or less. The removal. The method of claim 30 or 36 for preparing a thin film touch sensor further includes the step of attaching a circuit board to the pad electrode after removing the carrier substrate. The method of claim 35 for preparing a thin film touch sensor further comprising the step of attaching a circuit board to the pad pattern layer after removing the carrier substrate.