KR20150009310A

KR20150009310A - Method of preparing winow substrate for touch screen

Info

Publication number: KR20150009310A
Application number: KR20130083639A
Authority: KR
Inventors: 박대출; 김종민; 박일우
Original assignee: 동우 화인켐 주식회사
Priority date: 2013-07-16
Filing date: 2013-07-16
Publication date: 2015-01-26

Abstract

The present invention relates to a method for manufacturing a window substrate used in a touchscreen. The method enables a variety of processes performed on both surfaces of the window substrate to be easily conducted. The method includes the steps of: attaching a protection layer on a touch sensing electrode pattern after forming the pattern on a surface of the window substrate; and post-processing the window substrate after flipping the window substrate over by using a reversal device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing a window substrate for a touch screen,

The present invention relates to a manufacturing method of a window substrate for a touch screen, and more particularly, to a manufacturing method in which manufacturing of a window substrate can be easily performed.

2. Description of the Related Art [0002] In general, a touch screen is widely used as an input device for recognizing a user's touch on a display screen, such as various display devices and mobile devices.

Various recognition techniques and structures such as resistive type, electrostatic capacity type, and ultrasonic type are applied to the touch screen. In recent years, capacitive touchscreens have been increasingly being applied, attracting attention due to advantages such as multi-touch input and excellent durability. Such a capacitance type touch screen recognizes a position where a user touches and contacts by using a sensor pattern formed of a transparent conductive material such as ITO (Indium Tin Oxide) on a surface of a window substrate (also referred to as a cover lens).

The touch screen may be manufactured by forming a patterned transparent electrode layer for sensing a touch using a technique of depositing a transparent conductive material on one side of a window substrate. In the case of a touch screen manufactured by forming a transparent electrode layer on a window substrate, the transparent electrode layer is formed directly on the window substrate and then cut according to the unit window substrate shape.

However, in this case, in order to prevent damage and contamination of the transparent electrode layer formed on one surface of the window substrate, the protection layer is bonded onto the transparent electrode layer, and thereafter, the process of cutting the window disk, The protective layer may be bonded to the other surface of the window substrate where the transparent electrode layer is not formed.

However, the above-described post-processes are not only processes performed on both sides of the window substrate, but also require high precision.

In order to solve such a problem, Korean Patent Laid-Open Publication No. 2011-0059221 has proposed a glass processing apparatus for a touch screen panel capable of moving a window substrate on X axis, Y axis, and Z axis. However, the machining apparatus disclosed in Korean Patent Laid-Open Publication No. 2011-0059221 is applicable only to chamfering of a window substrate that has already been cut, which is not applicable to a process before cutting.

Patent Document 1: Korean Patent Publication No. 2011-0059221

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of manufacturing a window substrate for a touch screen which can be more easily performed.

It is another object of the present invention to provide a manufacturing method capable of easily performing double-side machining of a window original before a cutting process for manufacturing a unit window substrate.

1. Attaching a protective layer on the pattern after bonding a touch-sensitive electrode pattern to one surface of a window substrate; And reversing the window substrate using an inversion device and then post-processing the window substrate.

2. The method of claim 1, wherein the post-processing is a step of attaching a protective layer to the other surface of the window substrate.

3. The method of claim 1, wherein the post-processing is a step of cutting a window substrate.

4. The method of manufacturing a window substrate for a touch screen according to claim 1, wherein the post-processing is a step of polishing a cut surface of the window substrate.

5. The method of claim 1, wherein the post-processing is a step of etching the cut surface of the window substrate with an etchant.

6. The method of claim 1, wherein the window substrate is made of glass, polyethersulphone (PES), polyacrylate (PAR), polyetherimide (PEI), polyethyelene napthalate (PEN) Poly (ethylene terephthalate), polyphenylene sulfide (PPS), polyallylate, polyimide, polycarbonate (PC), polycarbonate (PC), cellulose triacetate And at least one selected from the group consisting of cellulose acetate propionate (CAP).

8. The method of manufacturing a window substrate for a touch screen according to 7 above, wherein the glass is reinforced glass.

9. The manufacturing method of a window substrate for a touch screen according to any one of claims 1 to 8, further comprising a step of reversing the window substrate at least once.

The method of manufacturing a window substrate of the present invention can easily perform various processes in which a window substrate is performed on both sides by using an inversion process of a window substrate, thereby reducing a defect rate.

In addition, the reversing process of the window substrate according to the present invention can be particularly advantageously applied by facilitating the processing of both sides of the window original plate in the process of processing the original plate before cutting the window substrate.

1 is a schematic perspective view of a mobile phone, an example of which is applied with a touch screen panel.
2 is a schematic vertical sectional view of a window substrate on which a nonconductive shielding pattern is formed.
3 is a vertical sectional view showing a schematic structure of a laminated structure laminated on one side of a window substrate.
4 is a view schematically showing an embodiment of a method of manufacturing a window substrate for a touch screen of the present invention including an inversion process according to the present invention.

The method includes forming a touch-sensitive electrode pattern on one side of a window substrate and then attaching a protective layer on the pattern; And reversing the window substrate using an inversion device and then performing post-processing on the window substrate, thereby making it possible to easily perform various processes of performing the window substrate on both sides, .

Hereinafter, a manufacturing method of a window substrate for a touch screen of the present invention will be described in more detail.

First, a touch sensing electrode pattern is bonded to one surface of a window substrate, and then a protective layer is attached to the pattern.

The window substrate 10 used in the present invention is not particularly limited as long as it is durable enough to sufficiently protect the touch screen panel from external force and is a material that allows the user to view the display well. Can be used without any particular limitation. For example, glass, polyethersulphone (PES), polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET) polyethyelene terepthalate, polyphenylene sulfide (PPS), polyallylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC), cellulose acetate propionate acetate propionate, CAP), and the like can be used. Preferably, glass can be used, and more preferably, tempered glass can be used.

As shown in FIG. 1, a window substrate is divided into a display unit on which an image is displayed and on which a touch sensor is disposed, and a non-display unit surrounding the display unit. The non-display portion functions to conceal the opaque conductive wiring pattern and various circuits, and prints a trademark or logo of a mobile phone maker as necessary.

Therefore, as shown in FIG. 2, a nonconductive shielding pattern 20 may be formed in a region corresponding to the non-display portion before the touch sensing electrode pattern is formed on the window substrate 10. The nonconductive shielding pattern 20 is formed on the window substrate 10 by a method such as screen printing.

The nonconductive shielding pattern 20 is formed to have an appropriate thickness for concealing various electrodes, wirings and the like stacked thereon. For example, the thickness may be 1 to 10 mu m, and preferably 1 to 5 mu m. When the thickness of the nonconductive shielding pattern 100 is within the above range, reliability of the conductive electrode pattern layer can be improved while shielding and shielding the substrate, wiring, have.

Alternatively, after the nonconductive shielding pattern 20 is formed on the non-display area on the window substrate 10, a transparent dielectric layer (index matching layer, IML) may be further provided. The transparent dielectric layer can be formed to improve the optical uniformity of the touch screen panel and is formed including niobium oxide, silicon oxide, or mixtures thereof.

After the nonconductive shielding pattern 20 is formed in the non-display area of the window substrate 10, the transparent electrode layer 40 is bonded to the display area. The transparent electrode layer used in the touch screen panel has various lamination structures known in the art, and the transparent electrode layer according to the present invention is not particularly limited. Various methods such as a method of directly depositing a transparent electrode on a window substrate or a method of directly bonding a transparent electrode layer to a window substrate are known in the art. In the present invention, Not limited.

In order to explain the present invention, a transparent electrode layer has a structure in which two layers are formed with an insulating layer sandwiched therebetween, and the transparent electrode layer is separately manufactured and then bonded to a window substrate. The present invention is not limited thereto.

Fig. 4 shows a schematic view of the laminated structure formed on the window substrate 10. As shown in Fig.

The transparent electrode layer 40 includes a first transparent sensing electrode 41a, a second transparent sensing electrode 41b, and an insulating layer 42 interposed between the electrodes. The transparent electrode layer 40 is bonded to the window substrate 10 via the adhesive layer 30.

The transparent sensing electrodes 41a and 41b are electrodes for sensing the position to be touched, and typically comprise electrodes for sensing the x-axis coordinate and the y-axis coordinate. For example, if the first transparent sensing electrode 41a is an electrode for sensing the x axis coordinate of the touch position, the second transparent sensing electrode 41b may be an electrode for sensing the y axis coordinate of the touch position, The opposite is also possible. In addition, the first transparent sensing electrode 41a and the second transparent sensing electrode 41b are formed in a predetermined pattern. The specific form of the pattern can be applied without limitation to a form known in the art.

The transparent sensing electrodes 41a and 41b may be formed using any conductive material used in the art without limitation and may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO) Zinc tin oxide (IZTO), cadmium tin oxide (CTO), poly (3,4-ethylenedioxythiophene), carbon nanotubes (CNT), and metal wires. These may be produced singly or in combination of two or more.

After the transparent electrode layer 40 is bonded to the window substrate 10, a protective layer 50 for protecting the transparent electrode layer 40 is attached. The protective layer 50 may be a polymer film used in the art such as PVC, PET, PE, etc. without limitation.

The window substrate 10 to which the transparent electrode layer 40 and the protective layer 50 are attached as described above may be a unit window substrate cut into a unit product size or may be a disc window substrate before cutting into a unit product size . In terms of productivity of the touch screen panel, it is preferable that the window glass substrate is a disk window substrate.

Next, the window substrate is turned upside down using an inversion device, and then the window substrate is post-processed.

After the transparent electrode layer 40 is bonded to the window substrate 10, various post-processing processes are performed. For example, if the window substrate 10 is in an original state before cutting, a cutting process can be performed, and a cutting process and etching process may be performed after the cutting process, . In addition, a process of attaching the protective layer to the surface of the window substrate 10 on which the transparent electrode layer 40 is not bonded in the post-processing step may be performed to protect the surface.

In particular, the process of attaching the protective layer to the surface of the window substrate 10 on which the transparent electrode layer 40 is not bonded may be performed in the same manner as in the previous process, It is necessary to provide a device for attaching a protective layer on both sides of the window substrate 10 because the protective layer 50 should be formed on the side opposite to the side where the protective layer 50 is attached. Such a problem can be more serious when the window substrate 10 is a disk, since it becomes a large area.

Therefore, the present invention is a method of reversing (reversing) the window substrate 10 by using a reversing device for post-processing of the window substrate 10 having the transparent electrode layer 40 and the protective layer 50 on one side, Process.

5 schematically shows a step of bonding the second protective layer 51 to a surface of the window substrate 10 on which the transparent electrode layer 40 is not bonded, as an example of post-processing. Through such an inversion process, the post-processing of the window substrate having the transparent electrode layer bonded to one surface can be performed more easily, and the post-processing can be performed without any additional equipment for post-processing. Further, since it is not necessary to provide facilities on both sides, it is not necessary to adjust the positions of the two side equipment, and post-processing can be performed only on one side, so that the precision of the process can be improved.

Another embodiment of post-processing includes a cutting process. Even in the cutting process of the window substrate 10, a longer time is required if the cutting process is performed only on one side, but the cutting process can be performed faster if the both sides are cut at the same time.

The cutting of the window substrate 10 can be applied without particular limitation to the method used in the art. Examples include mechanical, optical, and chemical cutting methods.

The mechanical cutting method mechanically scans the glass plate by dragging the diamond or carbide drawing wheel across the glass surface, and then cutting the glass plate along the scale to produce a cut edge. Typically, such a mechanical cutting method results in a lateral crack at a depth of about 100 to 150 탆, which cracks originate from the cutting line of the chewing wheel. Since the lateral crack lowers the strength of the window substrate, it is necessary to polish and remove the cut portion of the window substrate.

The optical cutting method is a non-contact cutting method using a laser. Examples of the laser cutting method include a thermal shock method, a laser ablation method, and a laser filamentation method, but the present invention is not limited thereto.

The thermal shock method is a method in which heat is transmitted to a window substrate by a laser, specifically, by exposing the window substrate to a high temperature and a high pressure for a very short time, or by heating the window substrate to a high temperature and quenching, And cutting it. When the window substrate receives a thermal shock, the temperature difference between the inner face and the back face causes thermal stress, breakage, and erosion deformation, which may cause the window substrate to be cut.

The laser usable in the thermal shock method is not particularly limited, and examples thereof include a CO ₂ laser and an excimer laser.

The wavelength of the laser usable in the thermal shock method is not particularly limited, and may be, for example, 5 to 12 占 퐉, and preferably 8 to 11 占 퐉. It is possible to cut the window substrate into a uniform cut surface without breakage in the wavelength range.

The laser ablation method is a method of cutting a surface of a window substrate by irradiating a laser beam having a short pulse shape with a low intensity. At this time, the free electrons of the generated laser beam hold energy, and when the free electrons contact the surface of the window substrate, thermal diffusion occurs due to the thermal energy of the electrons, and energy is transferred. The energy of the electron generated by the thermal diffusion process is changed from the surface of the window substrate to the lattice form. This lattice-shaped energy is emitted from the surface of the window substrate at the corresponding position, and at the same time, a part of the window substrate at the corresponding position is removed.

Examples of the laser usable in the laser ablation method include Nd: YAG laser, Nd: YVO4 laser, Ti: sapphire laser, CO ₂ laser, excimer laser and the like.

The pulse of the laser which can be used in the laser ablation method is not particularly limited, and may be, for example, 10 fs to 1000 ns, and preferably 100 fs to 500 ns. The window substrate can be cut into a uniform cut surface without breaking in the pulse range.

The laser filamentation method is a method of cutting a window substrate by irradiating a laser beam with a focus on the inside of the window substrate. Specifically, as the microwave laser beam passes through the window substrate, a portion of the microwave laser beam is absorbed to transfer energy to the constituent molecules. Due to the characteristics of the microwave laser pulse having a high energy density, the energy density absorbed is also high, A plasma is formed. Such a plasma may also affect the optical characteristics of a subsequent pulse when a continuous pulse is input. The plasma thus generated is annihilated after a certain life time, which may be transformed into a structure different from that of the surrounding materials. However, depending on the cutting processing conditions, the plasma is irradiated at a portion irradiated with the microwave laser beam, And the window substrate can be cut by extending the empty space.

The void space generated by the filamentation method is distinguished from a gap or crack caused by thermal expansion. The thermal expansion consisting of only thermal energy by the laser is a function of the structural transformation The gap due to this is not formed to be long and thin in the thickness direction, the shape is irregular, and the growth direction of the gap also shows a statistical characteristic somewhat.

Examples of the laser usable in the laser filamentation method include, but are not limited to, Nd: YAG laser, Nd: YVO4 laser, Ti: sapphire laser, excimer laser and the like.

The pulse of the laser usable in the laser filamentation method is not particularly limited, and may be, for example, 10 fs to 100 ns, and preferably 100 fs to 1000 ps. The window substrate can be cut into a uniform cut surface without breaking in the pulse range.

The chemical cutting method is a method in which a window substrate is impregnated into an etchant capable of etching a window substrate, and the region to be cut is etched by etching. For this purpose, it is necessary to attach a protective layer to the area excluding the cutting portion.

Such a chemical cutting method may be performed alone or after forming the groove along the cutting line on the window substrate by the mechanical cutting or optical cutting method described above.

Such a chemical cutting method using the etching solution has an advantage that a uniform shape and dimensions of the etched section of the glass substrate can be secured.

The etchant may be a conventional etchant of the art capable of etching the window substrate, preferably an acidic solution having a pH of 1.0 to 2.5. For example, a hydrofluoric acid (HF) aqueous solution is used as the etchant. If necessary, the etchant may further include an alcohol or the like as a solvent, and may further contain an additive such as a surfactant.

As another embodiment of the post-processing, there may be mentioned a step of polishing the cut surface.

Since the cut surface of the window substrate 10 subjected to the cutting process is uneven, it is necessary to polish the surface of the window substrate 10 by polishing it. A conventional polishing process is a method of polishing the abrasive wheel in contact with a cutting surface.

The abrasive surface in contact with the cut surface of the window substrate of the abrasive wheel may typically include diamond particles, abrasive, carbide particles, etc. as a cutting medium interspersed with a suitable matrix, i.e., a binder (e.g., a resin or metal bond matrix).

The particle size of the cutting medium may be 200 to 1200 mesh, preferably 250 to 1000 mesh, more preferably 400 to 800 mesh. When the particle size of the cutting medium is within the above range, the emboss pattern of the specific size and ratio can be formed on the chamfered portion, and the strength and elongation can be improved.

The grinding wheel can move along the cut portion while being in contact with the cut portion.

The moving speed of the grinding wheel along the cut portion of the window substrate may be 100 to 800 mm / sec, preferably 150 to 700 mm / sec, and more preferably 200 to 600 mm / sec. When the moving speed of the grinding wheel is within the above range, the emboss pattern of the specific size and ratio can be formed in the chamfered portion, and the strength and elongation can be improved.

When the grinding wheel is circular, the grinding can be performed while rotating the wheel. The rotation speed of the grinding wheel is not particularly limited and can be appropriately selected so that the emboss pattern according to the present invention can be formed through the etching step thereafter, For example, 10,000 to 50,000 rpm, preferably 12,000 to 45,000 rpm, and more preferably 15,000 to 40,000 rpm.

As another embodiment of the post-processing, the etching process of the cut surface can be mentioned.

The etching process of the cut surface improves the smoothness of the cut surface and prevents the cracking of the corner portion due to a minute crack, thereby enhancing the stability.

The etching method is not particularly limited. For example, the window substrate may be immersed in an etchant commonly used in the art, or the etchant may be sprayed onto the chamfered portion. Preferably, the window substrate is immersed in an etchant Can be performed. For this purpose, it is necessary to attach a protective layer to the area except the cut surface.

The etchant used in the etching process of the cut surface may be the same as the etchant mentioned in the chemical cut process described above.

In the present invention, the inversion process may be performed at least once more, if necessary, during the above-described post-processing, and the number of times is not particularly limited.

10: window substrate 20: nonconductive shielding pattern
30: adhesive layer 40: transparent electrode layer
41a: first transparent sensing electrode 41b: second transparent sensing electrode
42: insulating layer 50, 51: protective layer

Claims

Bonding a touch sensing electrode pattern to one side of a window substrate and attaching a protective layer on the pattern; And
Reversing the window substrate using an inversion device and finishing the window substrate;
And a step of forming the window substrate.

The method of claim 1, wherein the post-processing is a process of attaching a protective layer to the other surface of the window substrate.

The method of claim 1, wherein the post-processing is a step of cutting a window substrate.

The method of claim 1, wherein the post-processing is a step of polishing the cut surface of the window substrate.

The method of claim 1, wherein the post-processing is a step of etching the cut surface of the window substrate with an etchant.

[2] The method of claim 1, wherein the window substrate is made of glass, polyethersulphone (PES), polyacrylate (PAR), polyetherimide (PEI), polyethyelenenaphthalate (PET), polyethyelene terepthalate (PET), polyphenylene sulfide (PPS), polyallylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC) and cellulose acetate Wherein the substrate is formed of at least one selected from the group consisting of cellulose acetate propionate (CAP).

7. The method of claim 6, wherein the glass is reinforced glass.

The method of any one of claims 1 to 7, further comprising the step of reversing the window substrate at least once.