TWI817270B - Integrated touch module and touch display device comprising the same - Google Patents

Abstract

The present invention relates to an integrated touch control module and a touch display device. The integrated touch module has a touch sensing structure formed on a polymer film. Wherein, the polymer film, a liquid crystal phase retardation layer and a linear polarizing layer constitute a circular polarizing element, the average reflectance of the circular polarizing element in the visible light range is less than 5% and the standard deviation of the reflectance is less than 0.2%. The touch display device includes the integrated touch module.

Description

Integrated touch module and touch display device including the integrated touch module

The present invention relates to an integrated touch module and a touch display device including the integrated touch module. In particular, it relates to an ultra-thin integrated touch module that is bendable and has a wide wave range. A set and a touch display device including the integrated touch module.

Currently, Circular Polarizer (CPOL) is mainly composed of a phase retardation layer (Retarder) and a linear polarizer. It is often used as an anti-reflective film in the display field to solve the problem of incident light from the external environment. The reflected light reduces display problems. The phase retardation layer used can be a quarter wave plate (QWP). Figure 1 is a schematic diagram illustrating the anti-reflection sheet receiving incident light from the external environment. As shown in Figure 1, theoretically, when the incident light L from the outside passes through the outermost linear polarizing layer 10a, the linear polarizing layer 10a converts the incident light L into linearly polarized incident light L ₁ , and the linearly polarized incident light L ₁ The polarization direction is the vertical direction. Then, the linearly polarized incident light L ₁ enters the 1/4 wave plate as the phase retardation layer 20 a, causing the linearly polarized incident light L ₁ to undergo phase retardation, and converts the linearly polarized incident light L ₁ into left-handed rotation. Polarized light L _cl ; then, when the light is reflected by the display panel 200 , it will form reverse right-handed polarized light L _cr , and then pass through the 1/4 wave plate as the phase retardation layer 20 a , finally making the linearly polarized incident light L ₂ The polarization direction is orthogonal to the polarization direction of the linearly polarized incident light L ₁ , so that the incident light from the external environment cannot pass through the linear polarizing layer 10 a and is blocked in the circular polarizer. From the above principle, the circular polarization of external ambient light by the anti-reflective sheet is the first step of the above-mentioned anti-reflective mechanism, so it is one of the important factors of the anti-reflective effect. In fact, the phase retardation layer cannot detect the visible light range. All incident light in the display panel 200 undergoes ideal circular polarization, causing ambient light of certain wavelengths to still be reflected by the display panel 200 , causing interference when the user views the screen.

The Republic of China Patent No. I663460 (hereinafter referred to as Patent I663460) discloses a wide-wavelength phase compensation laminate, including an optically active half phase compensation coating film and an optically active quarter phase compensation coating film. The optically active one-quarter phase compensation coating film and the optically active one-half phase compensation coating film are in direct contact with a contact surface. The wide-wave domain phase compensation laminate disclosed in patent I663460 is a technical solution proposed to solve the above problems. For example, paragraph [0014] of patent I663460 mentions that "the compensation film has the ability to convert circularly polarized light into wide-wave domain compensation." membrane".

However, the reflectivity of the compensation film of patent I663460 in the visible light range is still too high, and it cannot effectively eliminate the reflection problem of ambient light. For example, as shown in Table 3 of patent I663460, the compensation film of patent I663460 has a reflectivity of 450nm, 550nm, and 650nm at wavelengths of 450nm, 550nm, and 650nm. Reflectivity is approximately 8%. Since circular polarizers are mainly used to resist ambient light reflection, the higher the reflectivity, the worse the anti-ambient light reflection effect, which may affect the display effect of the end product, causing reflections under strong external light, causing reading interference; and this The application believes that the reflectivity (8%) of the compensation film in the patent I663460 in the visible light range cannot meet the increasingly sophisticated display needs, especially at present, high-resolution and high-quality videos such as 4K and 8K have been favored by users. It is worth noting that Table 4 of patent I663460 discloses a compensation film with a reflectivity of about 4~5%. However, compared with the embodiment in Table 3, patent I663460 does not clearly explain what factors cause the difference in reflectivity. Therefore, technicians Don't know how to implement it.

On the other hand, the materials of the optically active half phase compensation coating and the optically active quarter phase compensation coating of patent I663460 both use anisotropic liquid crystal (also called a liquid crystal phase retardation layer). Currently, touch-sensing electrodes are assembled on displays as the touch-sensitive display screen is one of the important human-machine interfaces. In order to make the product thinner, the touch-sensing electrodes will be integrated into other components as much as possible. The patent I663460 uses The anisotropic liquid crystal cannot be directly used as a substrate for lamination and assembly with the touch sensing structure during the manufacturing process. An adhesive layer and/or substrate must be used as a load-bearing material to provide structural strength. In this way, the touch sensing electrodes and anti-reflective elements cannot be combined. Reducing the thickness of the chip after integration does not conform to the current trend of increasingly thinner displays, so it is necessary to improve it.

Furthermore, in the optical film industry, in order to achieve production efficiency and material matching, a half phase compensation layer (or Half Wave Plate, HWP) of the same material type is usually used. A combination of quarter phase compensation layers (or Quarter Wave Plate, QWP). For example, patent I66346 uses the same liquid crystal material to make a half phase compensation layer and a quarter phase compensation layer. . It cannot be denied that there are some documents that disclose in a schematic manner an optical film combination of a polymer stretched type half phase compensation layer and a polymer stretched type quarter phase compensation layer. However, before this application, there was no document that truly taught or suggested the use of optical film combinations of different material types from the perspective of problem solving, the integration of optical effects and electrical signal functions, and the integration of the two components in the manufacturing process.

Therefore, in view of the above deficiencies, the present invention was produced.

The object of the present invention is to provide an integrated touch module, wherein the integrated touch module is integrated with an electrical signal processing element (touch sensing structure) and an optical element (phase retardation layer/polarizing layer). Two components with different characteristics/functions can be matched without compromising their respective characteristics. At the same time, the product can be thinned to meet the needs of integration, thereby realizing a bendable and ultra-thin integrated touch module.

Another object of the present invention is to provide an integrated touch module, wherein the average reflectivity of the circularly polarizing element included in the integrated touch module in the visible light range is less than 5% and the standard deviation of the reflectivity is less than 0.2 %, with this, an integrated touch module with high and uniform wide-wavelength anti-reflection rate can be realized. The wide-wavelength domain refers to covering the visible light range (450nm-675nm), which means that the integrated touch module of the present invention has uniform and consistent phase delay characteristics and low reflection characteristics in the entire visible light range.

Another object of the present invention is to provide an integrated touch module, in which the polymer film of the integrated touch module can be directly used as a substrate to form a touch sensing structure thereon without the need for additional After the substrate is set and the touch sensing structure is manufactured, the polymer film can retain its original optical properties.

The integrated touch module of the present invention includes: a nanosilver wire touch sensing structure formed on a polymer film. The polymer film has a phase retardation value between 100nm and 160nm at a wavelength of 550nm. ; Wherein, the polymer film, a liquid crystal phase retardation layer and a linear polarizing layer form a circular polarizing element, the average reflectance of the circular polarizing element in the visible light range is less than 5% and the standard deviation of the reflectance is less than 0.2%.

Preferably, according to the integrated touch module of the present invention, the average reflectivity of the integrated touch module in the visible light range is less than 6% and the standard deviation of the reflectivity is less than 0.4%.

Preferably, according to the integrated touch module of the present invention, the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm is less than 6%, and the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm is less than 6%. The difference between reflectance and reflectance at 550nm wavelength is less than 5%. Or the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm is less than 6%, and the difference between the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm and the reflectance at the wavelength of 550nm is less than 4.5% or less 3.5%.

Preferably, according to the integrated touch module of the present invention, the reflectance difference between the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm and the average reflectance in the wavelength range of 525nm-675nm is less than 10%. Or the reflectance difference between the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm and the average reflectance in the wavelength range of 525nm-675nm is less than 7% or less than 5.5%.

Preferably, according to the integrated touch module of the present invention, the polymer film can withstand the processing temperature of the silver nanowire touch sensing structure.

Preferably, according to the integrated touch module of the present invention, the glass transition temperature of the polymer film is greater than or equal to the highest process temperature for manufacturing the silver nanowire touch sensing structure on the polymer film.

Preferably, according to the integrated touch module of the present invention, the polymer film is a positive dispersion type phase retardation layer with a thickness of about 25 μm; the liquid crystal type phase retardation layer is a positive dispersion type phase retardation layer. The thickness is about 2 μm. The optical axis difference between the polymer film and the liquid crystal phase retardation layer is about 60 degrees. The liquid crystal phase retardation layer has a phase retardation value between 230nm and 310nm at a wavelength of 550nm. .

Preferably, according to the integrated touch module of the present invention, the maximum process temperature of the silver nanowire touch sensing structure is 135-140°C, and the main component of the polymer film is methyl methacrylate. (PMMA), cyclic olefin polymer (COP), polycarbonate (PC), polyethylene terephthalate (PET), colorless polyimide (CPI) or derivatives of the above compounds, and their glass transition The temperature is greater than or equal to 135-140℃.

Preferably, according to the integrated touch module of the present invention, the silver nanowire touch sensing structure includes: a silver nanowire electrode layer disposed between the polymer film and the liquid crystal phase retardation layer. between.

Preferably, according to the integrated touch module of the present invention, the silver nanowire touch sensing structure includes: two silver nanowire electrode layers, and the silver nanowire electrode layers are respectively disposed on the phase. The upper surface and the lower surface of the polymer positive dispersion rate phase retardation layer.

Preferably, the integrated touch module according to the present invention further includes: a linear polarizing layer disposed above the phase retardation layer.

In addition, the present invention further provides a touch display device, including: a display panel having a display area; and the above-mentioned integrated touch module disposed on the display panel, wherein the touch module of the touch module The sensing structure correspondingly overlaps the display area.

Preferably, according to the touch display device of the present invention, the touch display panel is a liquid crystal display panel, an organic electroluminescent display panel, an organic light emitting diode display panel, or a micro light emitting diode display panel. However, , the present invention is not limited thereto.

In order to enable those with ordinary knowledge in the art to understand the purpose, features and effects of the present invention, the present invention is described in detail through the following specific embodiments in conjunction with the accompanying drawings.

The advantages, features and methods of achieving the present invention will be apparent from the following description of exemplary embodiments according to the present invention in more detail with reference to the accompanying drawings. However, it should be noted that the present invention is not limited to the following exemplary embodiments, but may be implemented in various forms.

The terminology used herein is for describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" include the plural forms unless the context clearly indicates otherwise.

Additionally, it will be understood that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may be present. In addition, the thickness values mentioned in this article are not absolute. Those of ordinary skill in the art can understand that the thicknesses mentioned may include manufacturing tolerances, measurement errors, etc. Preferably, the thicknesses listed in this article may have a range of 10% or 20%. .

It should also be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish between various components. Thus, a first element in some embodiments could be termed a second element in other embodiments, without departing from the teachings of the present invention. In this specification, the same reference numbers indicate the same elements. In addition, optical elements will be used interchangeably with "plate", "layer", "film" or other similar terms in this article. Unless otherwise specified, the differences are only in name.

It is worth mentioning that since the present invention relates to the phase retardation value of the phase retardation material, the measurement method will be described below. The embodiment of the present invention measures the phase retardation value measured on a plane perpendicular to the thickness direction of the object to be measured, that is, the in-plane phase retardance value (in plane retardance/retardation (R ₀ )). The embodiment of the present invention uses commercial equipment model: AxoScan (manufacturer Axometrics, Inc) to measure the in-plane phase retardation value of the object under test in the visible light wavelength range. For the sake of data simplicity, this article only records specific wavelengths, such as starting from 450nm, every 25nm Record the in-plane phase retardation value once up to 675nm. That is to say, the visible light wavelength range referred to in this article is 450nm-675nm, and the so-called wide-wavelength domain in the present invention can also be understood as the wavelength range of 450nm-675nm.

The present invention provides a first comparative example of an integrated touch module. The integrated touch module includes: a polymer phase retardation layer and a touch sensing structure disposed on the polymer phase retardation layer, as described above. , in order to integrate electrical signal processing elements (touch sensing structure) and optical elements (polymer phase retardation layer), that is to say, the touch sensing structure is directly formed on the polymer phase retardation layer without the need for additional substrates. material to carry the touch sensing structure. The combination of a polymer phase retardation layer and a linear polarizing layer/polarizing layer can form an anti-reflective optical element, which can be called a circular polarizer (or circular polarizing element). In order to achieve the aforementioned integration and product thinning purposes, the polymer phase retardation layer uses cyclic olefin polymer (COP) with a thickness of 45um, which can be used as a quarter phase compensation layer. Compared with the currently commercially available polymer stretch type The quarter phase compensation layer, the 45um thick cyclic olefin polymer (COP) has been reduced by 50% in thickness.

In addition, in some embodiments of the present disclosure, the linear polarizing layer/polarizing layer can be a generally commercially available polarizing plate with a degree of polarization (DOP) greater than 98%, but is not limited thereto. The linear polarizing layer/polarizing layer can be two protective films (such as triacetyl cellulose, TAC) with polyvinyl alcohol (PVA) material fixed in the middle (referred to as type A polarizing layer), or a single protective film (such as TAC) and The combination of polyvinyl alcohol (PVA) materials (referred to as type B polarizing layer), the above two polarizing layers or any other form of polarizing layer are applicable to the present invention, and are not limited to the embodiments.

According to an experimental method of the present disclosure, incident light is used to enter the object to be measured (such as the combination of the above-mentioned polymer phase retardation layer, touch sensing structure, and linear polarizing layer) and then pass through a reflective surface, such as a semi-conductor with a reflectivity of about 55%. The reflector (manufacturer: 3D Lens) passes through the object to be measured and reflects the light, and the reflectance (R%) spectrum in the visible light range can be measured accordingly. Generally speaking, the international standards related to optical measurement mainly include ASTM D1003, CIE 130 1998, and ISO 13468. This article uses the structure of ASTM D1003 for measurement.

Please refer to Table 1 and Figure 2. Figure 2 plots the reflectance of the 45um thick cyclic olefin polymer (COP) used in the first comparative example combined with the B-type polarizing layer versus the full wavelength (i.e. 450nm-675nm). Spectral curve chart, Table 1 captures the reflectance of the curve in Figure 2 at a specific wavelength; as shown in Table 1, the average reflectance of the first comparative example in the visible light wavelength range is between 5% and 6%, and the reflectance The standard deviation of The display screen has a color cast. From the analysis of Figure 2, the first comparative example is prone to high reflection in the short wavelength range of visible light. For example, in the wavelength range of 450nm-500nm, the average reflectance is close to 7% (based on the reflection of 450nm, 475nm, and 500nm in Table 1 The average rate is calculated as about 6.9%. Unless otherwise specified in this article, the data are calculated in a similar way), which means that the first comparative example will reflect the incident light with a wavelength of 450nm-500nm for the viewer to observe. According to the first comparative example, we found that when the phase retardation layer of the same polymer material is thinner (comparing the cyclic olefin polymer with a thickness of 45um selected in this example to other thicker commercial products), short Problems with high reflectivity (e.g. >6%) occur in the wavelength range. In addition, if the 550nm wavelength is regarded as the central area of the visible light range, the average reflectance of the short wavelength range can be compared with the reflectance of the 550nm wavelength to understand whether there is a sudden change in the reflectance. According to the calculation, the first comparison The average reflectance of the example in the wavelength range of 450nm-500nm is quite different from the reflectance of the 550nm wavelength, the difference is about 55% (calculation formula: (6.9-4.47)/4.47=54.4%). It is obvious that the first comparative example is The reflectivity in the short wavelength range will suddenly change. For the human eye, a large amount of reflected light in the short wavelength range will suddenly be felt, which will cause poor and uneven viewing quality. Furthermore, if the visible light is divided into two sections: the short wavelength range and the medium and long wavelength range, the change in reflectivity can also be analyzed from the average reflectivity difference between the short wavelength range and the medium and long wavelength range. According to calculations, first The difference in reflectance between the average reflectance in the wavelength range of 450nm-500nm (i.e., the short wavelength range) and the average reflectance in the wavelength range of 525nm-675nm (i.e., the medium and long wavelength range) of the comparative example is approximately 33% (calculation formula: (6.9) -4.63)/6.9=32.9%), it is obvious that the reflectivity of the first comparative example has great variation in the two wavelength ranges.

Table 1 Wavelength (nm) Reflectivity ( % ) 450 8.20 475 6.83 500 5.69 525 4.90 550 4.47 575 4.31 600 4.35 625 4.53 650 4.78 675 5.1 average value 5.31 standard deviation 1.21

Table 2 shows the reflectivity under specific visible light obtained by making a silver nanowire touch sensing structure on a 45um thick cyclic olefin polymer (COP) and combining it with a B-type polarizing layer according to the above test method/equipment. And the average value and standard deviation calculated accordingly; as shown in Table 2, the average reflectance in the visible light range is 5.91%, and the standard deviation of the reflectance in the visible light range is 0.81%. In other words, after integrating the optical film (i.e., the quarter phase compensation layer of COP material) and the silver nanowire touch sensing structure, the reflectivity still varies greatly at each wavelength, especially in the short wavelength range. , the average reflectivity is close to 7%, which causes uneven display quality (such as color cast, etc.). In other words, regardless of whether there is an integrated touch sensing structure, the problem of high reflectivity in the short wavelength range found in the first comparative example needs to be solved.

Table 2 Wavelength (nm) Reflectivity ( % ) 450 7.75 475 6.65 500 5.99 525 5.38 550 4.89 575 5.00 600 5.35 625 5.73 650 6.13 675 6.22 average value 5.91 standard deviation 0.81

Please refer to FIG. 3. FIG. 3 is a schematic diagram of an integrated touch module according to a first embodiment of the present invention. The integrated touch module 100 according to the present invention includes: a polymer film 20, and a film disposed on the polymer film 20. Touch sensing structure 30 , liquid crystal phase retardation layer 23 and linear polarizing layer 10 . Among them, the polymer film 20 and the liquid crystal phase retardation layer 23 constitute a phase retardation element. The phase retardation value R ₀ (550) of the polymer film 20 at 550 nm can be between 100 nm and 160 nm, preferably at least 130 nm; the phase retardation value R ₀ (550) of the liquid crystal phase retardation layer 23 at 550 nm can be Between 230nm and 310nm, preferably at least 250nm. Specifically, the polymer film 20 is a polycarbonate (PC) material with a thickness of 25um (supplier: LONGHUA), and its phase retardation value at 550nm is 131nm, which is as high as the first embodiment of the present invention. The measured phase retardation value of the molecular film 20 when the incident light wavelength is 550 nm is very close to the ideal quarter-wavelength phase retardation value (138.75 nm). In this way, it can be determined that the polymer film 20 according to the first embodiment of the present invention can be used as a quarter phase retardation layer and at the same time as a substrate carrying the touch sensing structure 30 . In one embodiment, the slow axis of the polymer film 20 is approximately 75 degrees. The liquid crystal type phase retardation layer 23 is a single layer of liquid crystal coating, for example, made of a commercially available product: Reactive Mesogen (RM) reactive liquid crystal. The thickness is about 2um, the slow axis is about 15 degrees, and its phase retardation at 550nm The value is 260 nm. The phase retardation value measured when the incident light wavelength of the liquid crystal phase retardation layer 23 of the first embodiment of the present invention is 550 nm is very close to the ideal half phase retardation value (275 nm). In this way, it can be determined that the liquid crystal phase retardation layer 23 according to the first embodiment of the present invention can be used as a half phase retardation layer. In this embodiment, the optical axis (such as the aforementioned slow axis) of the polymer film 20 and the liquid crystal phase retardation layer 23 differs by about 60 degrees; the linear polarizing layer 10 is the above-mentioned B-type polarizing layer, which is the commercially available product SPN32- 1805M (supplier: SAPO), and the liquid crystal phase retardation layer 23 is bonded to the linear polarizing layer 10 through polyvinyl alcohol (PVA) based water glue.

In addition, both the polymer film 20 and the liquid crystal phase retardation layer 23 have positive dispersion characteristics. The positive dispersion referred here refers to the in-plane phase retardation value (retardation value) of the material as the wavelength increases. And reducing, it can also be said that the material has a small phase retardation value in the plane of long wavelength (such as 650nm), but a large phase retardation value in the plane of short wavelength (such as 400nm). In other words, R ₀ (650)/ R ₀ (400)>1. The combination of the polymer film 20 and the liquid crystal phase retardation layer 23 can obtain the characteristics of negative dispersion, and the optical effect presented by the negative dispersion characteristics will be closer to the theory. The inverse dispersion ratio referred to here refers to the increase in the phase retardation value (retardation value) of the material as the wavelength increases. It is worth mentioning that the forward and inverse dispersion referred to in this embodiment is only a rough trend and not a completely linear change. The description of the linear polarizing layer 10 can be found in the previous section and will not be repeated here.

Please refer to Table 3 and Figure 4. Figure 4 shows a phase retardation element and a linear polarizing layer 10 composed of a polymer film 20 and the aforementioned liquid crystal phase retardation layer 23 (excluding touch sensing) according to the first embodiment of the present invention. Structure 30) The spectral curve of reflectance and wavelength obtained by the above test method/equipment. Table 3 captures the reflectance of Figure 4 under specific visible light and calculates the average value and standard deviation accordingly; such as As shown in Table 3, the reflectance of the first embodiment of the present invention when the incident light wavelength is 550 nm is 4.54%, the average reflectance in the visible light range is 4.51%, and the standard deviation of the reflectivity in the visible light range is 0.17%, as shown in The low average reflectivity and low reflectivity standard deviation value clearly indicate that the present invention can provide an anti-reflective sheet with low and uniform reflectivity. Comparing Figure 4 with the spectrum of the first comparative example (i.e. Figure 2), it can be found that the first embodiment of the present invention has low reflectivity in the middle and low wavelength range of visible light, for example, in the wavelength range of 450nm-500nm, the average reflection The rate is 4.7% (calculated from the data in Table 3). Therefore, it can be shown that the first embodiment of the present invention has good optical properties and has a wide-wavelength phase delay that meets the needs of practical applications. Compared with the aforementioned comparative example, the difference between the average reflectance of the optical layer (excluding the touch sensing structure 30) of this embodiment in the wavelength range of 450nm-500nm and the reflectance of 550nm is quite small (calculation formula: (4.7 -4.54)/4.54=3.5%), compared with the first comparative example, the calculated difference value is 10 times as much. It is obvious that the reflectivity of this embodiment in the short wavelength range is quite uniform, which is good for the viewer. That said, you won't suddenly feel a large amount of obvious reflected light. If the reflectance difference between the average reflectance in the 450nm-500nm wavelength range (i.e. the short wavelength range) and the average reflectance in the 525nm-675nm wavelength range (i.e. the medium and long wavelength range) in this embodiment is also calculated, the calculation result is approximately 5.5% (calculation formula: (4.7-4.44)/4.7=5.5%). Compared with the first comparative example, the difference between the two is significantly reduced, so the display quality is also effectively improved.

table 3 Wavelength (nm) Reflectivity ( % ) 450 4.83 475 4.74 500 4.49 525 4.37 550 4.54 575 4.31 600 4.38 625 4.47 650 4.37 675 4.66 average value 4.51 standard deviation 0.17

In addition, according to the first embodiment of the present invention, the polymer film 20 can be directly used as a substrate. As shown in FIG. 3 , the touch sensing structure 30 of the first embodiment of the present invention can include a single-layer touch electrode layer. The single-layer touch electrode layer can be disposed on the polymer film 20 without the need for an additional substrate, greatly reducing the thickness of the integrated touch module 100, thereby achieving bendable and ultra-thin integration. touch modules and products. Specifically, in this embodiment, a slurry (supplier: Cambrios) containing silver nanowires (SNW) is coated on the polymer film 20, and then undergoes baking, solidification, patterning and other steps to form nanowires. Silver wire electrode (not shown in the figure), the specific method can be referred to and the full text is introduced into US20190227650A, CN101292362, etc. The nanosilver wire electrode has high transmittance, for example, the light transmittance (Transmission) in the visible light range is greater than about 88%, 90%, 91%, 92%, 93% or more. The formed silver nanowire electrodes are mainly located in the visible area for sensing touch purposes, and the silver nanowire electrodes must be overlapped with the wiring in the surrounding area to facilitate connection with external circuits (such as FPC). Signal transmission, this part can be achieved using general technology and will not be described in detail here. In addition to carrying nano silver wire electrodes, the polymer film 20 preferably has high strength, because the wiring in the peripheral area and the wires on the FPC are usually connected using a hot pressing process (i.e. bonding process). The polymer film 20 must provide supporting force to transmit the pressure of the hot pressing die to the connection point (i.e., the bonding area), so that the wiring and the wires on the FPC can be well fixed. In one embodiment, the strength of the polymer film 20 is expressed in terms of elastic modulus (elastic module), which is approximately between 2 and 72 Gpa.

In one embodiment, the polymer film 20 must be able to withstand the process temperature of forming the above-mentioned silver nanowire electrode, which refers to the highest temperature in the process of forming the above-mentioned silver nanowire electrode. Specifically, in this embodiment, the maximum temperature used in the step of making the nanosilver wire electrode is about 135-140°C (the error of the equipment, the influence of the surrounding environment, etc. need to be considered), and the polymer film 20 needs to be selected to withstand Materials that require a process temperature of 135-140°C to maintain their optical properties. More specifically, the material is usually selected based on the glass transition temperature of the polymer film 20. In one embodiment, the glass transition temperature of the polymer film 20 can be greater than or equal to the process temperature of 135-140°C to maintain its optical properties. Characteristics, the glass transition temperature of the polycarbonate (PC) material polymer film 20 used in this embodiment is 137-140°C. Basically, it can be considered that the glass transition temperature of the polymer film 20 in this embodiment is equal to the production of nanosilver. The process temperature of the wire electrode. It should be noted that the above process temperatures are only for example and are not used to limit the present invention.

Nanosilver wire electrodes (i.e., the touch sensing structure 30 ) are made on both sides of the polymer film 20 using the aforementioned method, and then optically transparent adhesive (OCA, not shown) is used to seal the liquid crystal phase retardation layer 23 and linear polarization layer 23 . The layer 10 is bonded to the polymer film 20 to form an integrated touch module 100 as shown in FIG. 3 . Table 4 shows the first embodiment of the present invention. The nanosilver wire touch sensing structure 30 is fabricated on both sides of the polymer film 20, and the liquid crystal phase retardation layer 23 and the linear polarizing layer 10 are combined with the above-mentioned testing method/equipment. The obtained reflectance under specific visible light, and the average value and standard deviation calculated accordingly; as shown in Table 4, the reflectance of the first embodiment of the present invention when the incident light wavelength is 550nm is 5.87%, in the visible light range The average reflectance is 5.85%, and the standard deviation of the reflectivity in the visible light range is 0.39%; the average reflectance of the integrated touch module 100 in this embodiment in the wavelength range of 450nm-500nm and the reflectance at the wavelength of 550nm The difference is quite small (about 2.2%). It is obvious that the reflectivity of this embodiment is quite uniform in the short wavelength range. From this, it can be seen that the present invention can provide an integrated touch module 100 with low and uniform reflectivity. It is worth mentioning that since the silver nanowire touch sensing structure 30 will cause an increase in reflectivity, the average value and standard deviation of the reflectivity are both lower than those without the silver nanowire touch sensing structure 30 . The data (ie Table 3) is high, but the increase is not large and can still meet the demand for final products. As mentioned above, patent I663460 discloses that the materials for the one-half phase compensation coating and the optically active one-quarter phase compensation coating are liquid crystal materials. The liquid crystal cannot be directly used as a substrate for molding the touch sensing structure 30 during the manufacturing process. . Therefore, compared with patent I663460, the present invention proposes a feasible integration solution of a touch sensing structure and a polymeric phase delay layer, which has better anti-ambient light reflection effect, and under this structure, the touch The sensing structure and the polymer phase retardation layer can be matched with each other, and the process conditions of the touch sensing structure 30 will not affect the optical properties of the polymer phase retardation layer. Furthermore, the polymer phase retardation layer can also meet the strength requirements of the substrate and the hot pressing process.

Table 4 Wavelength (nm) Reflectivity ( % ) 450 5.46 475 5.65 500 6.10 525 6.12 550 5.87 575 5.58 600 6.27 625 6.22 650 5.96 675 5.23 average value 5.85 standard deviation 0.39

The following describes a second comparative example of the present invention, which uses a polymer film 20 with a thickness of 15um (supplier: LONGHUA). Since the composition, thickness, and stretching conditions of the film material are different from those of the first embodiment, the height of the second comparative example is The glass transition temperature of the molecular film 20 is 128-130°C, which is lower than the 135-140°C process temperature for manufacturing the nanosilver wire electrode. Other conditions are the same as the previous embodiment. After testing, since the polymer film 20 in this comparative example cannot withstand the process temperature of the nanosilver wire electrode, the reflectivity of the polymer film 20 in the second comparative example of the present invention reaches 21 after being made into the structure of Figure 3 %, it is obvious that the polymer film 20 has lost its original optical properties. If the polymer film 20 of the second comparative example of the present invention is placed at a temperature of 140° C. for one hour to simulate the manufacturing process of the nanosilver wire electrode, and then its optical retardation value is measured, the experimental result shows that the optical retardation value is 2.05 (At a wavelength of 550 nm), this also proves that the polymer film 20 of the second comparative example of the present invention does not have an optical retardation effect after being subjected to high temperature (that is, the test temperature exceeds its glass transition temperature).

It is worth noting that the first embodiment and the second comparative example of the present invention use polymer films of the same main material, but have different glass transition temperatures. The description of this application is as follows: Since the first embodiment and the second comparative example use The sources of polymer raw materials are different, and different suppliers will have different compositions. That is to say, the main components of the mold materials of the first embodiment and the second comparative example are the same, but other components will be different, and the stretching Conditions can also cause differences in the properties of polymer membranes.

In addition to the polycarbonate (PC) used in the above-mentioned first embodiment, the present invention can be expected to be used as a material of the polymer film 20 based on the glass transition temperature of the polymer, such as the main component of the polymer film 20 (ie, the weight percentage is at least ＞50%) can be: methyl methacrylate (PMMA) with Tg＞146℃, published in the paper: Optical Poly(methyl methacrylate) copolymers Material with High Thermal Resistance (2017); commercially available cyclic olefins with Tg=165℃ Polymer (COP) products (supplier: Konica Minota); commercially available colorless polyimide (CPI) products with Tg > 180°C; commercially available polyethylene terephthalate (Tg) between 150-155°C PET) products or mainly composed of derivatives of the aforementioned compounds, and the phase retardation value measured at a wavelength of 550nm is between 100nm-200nm, or at least 130nm, or between 127nm-134nm, 135nm-145nm, 129nm In the range of -132nm, 130nm-131nm, the optical axis of the polymer film 20 is between 0-180 degrees, preferably 75 degrees. On the other hand, the measured phase retardation value of the liquid crystal phase retardation layer 23 in the visible light range according to the present invention is between 200nm and 300nm, or can be between 200nm and 288nm, 237nm and 279nm, and 259nm and 271nm. The optical axis of the phase retardation layer 23 is between 0-180 degrees, preferably 15 degrees. It can be understood that the above embodiment may be subject to the error of the measuring instrument, so the phase delay value is only an integer. The user can choose a measuring instrument with a smaller error range to measure the phase delay value according to the needs. Here, it is only an integer. By way of example, the invention is not limited thereto.

The thickness of the polymer film 20 used according to the first embodiment of the present invention is only about 25 μm, the thickness of the liquid crystal phase retardation layer 23 is only about 2 μm, and the total thickness of the overall phase retardation element is 27 μm; nanosilver wire electrode It is divided into two forms. One is that the driving electrode/sensing electrode is made on both sides of the polymer film 20, and the driving electrode/sensing electrode is 8.5um each. The other is that the driving electrode/sensing electrode is made on the same side of the polymer film 20. , the thickness of the driving electrode/sensing electrode is 10um. With this thickness, it is more conducive to realizing a bendable ultra-thin touch module. Therefore, the touch module and the product thereof according to the embodiment of the present invention further have the effect of being thinner.

The following describes the integrated touch module of the second embodiment of the present invention. The difference from the first embodiment is that the polymer film 20 is made of a material with a thickness of 28um (supplier: Osaka Gas), and its main component is polyterephthalene. Ethylene formate (PET), with a Tg of 151°C, has a phase retardation value of 132nm measured at a wavelength of 550nm.

Compared with the aforementioned comparative example, the average reflectance of this example in the wavelength range of 450nm-500nm (approximately 5.6% after calculation of experimental data) and the reflectivity at 550nm wavelength are only 4.5% different. It is obvious that the average reflectance of this example at short wavelengths The reflectivity in the range is quite uniform, and the viewer will not suddenly feel a large amount of obvious reflected light; furthermore, the average reflection in the 450nm-500nm wavelength range (i.e., the short wavelength range) in this embodiment The difference in reflectance between the reflectivity and the average reflectance in the wavelength range of 525nm-675nm (i.e. the medium and long wavelength range) is calculated to be approximately 7.0%. Based on the average reflectance of this embodiment in the wavelength range of 450nm-500nm, this application believes that both the integrated touch module of the second embodiment and the first embodiment can satisfy that the average reflectance of the circularly polarizing element in the visible light range is less than 5% and the standard deviation of the reflectivity is less than 0.2%. It can also meet the requirement that the average reflectance of the integrated touch module in the visible light range is less than 6% and the standard deviation of the reflectivity is less than 0.4%.

Furthermore, the integration solution of the touch sensing structure and the phase retardation layer of the present invention has a change rate of less than 5% in the phase retardation value when exposed to a high temperature (85°C) environment for a long time (500 hours), and has good weather resistance.

Other examples of touch modules are further provided below so that those with ordinary knowledge in the technical field to which the present invention belongs can more clearly understand the possible changes. The components represented by the same component numbers as in the above embodiment are essentially the same as those described above with reference to FIGS. 3 , 4 , and 7 . The components, features, and advantages that are the same as those of the integrated touch module 100 will not be described again. .

The difference between the third embodiment of the present invention and FIG. 4 is that the touch sensing structure 30 of the integrated touch module 100 of this embodiment may include a first touch electrode layer (such as a driving layer) and a second touch electrode layer. The touch electrode layer (such as the sensing layer), the first touch electrode layer and the second touch electrode layer are disposed on the same side of the polymer film 20 , such as the side away from the display module, but not limited to this. For relevant descriptions of this embodiment, please refer to the foregoing description and will not be repeated here.

It can be understood that the placement position of the touch sensing structure 30 will not significantly affect the average reflectivity of the integrated touch module 100 in the visible light range, and those with ordinary knowledge in the technical field of the present invention can based on the above examples. Various changes and adjustments have been made, which are not listed here.

The following will describe embodiments in which the touch module according to the present invention is applied to a display device.

Please refer to FIG. 5 , which is a schematic structural diagram of a display device according to a preferred embodiment of the present invention. The display device 300 includes a display panel 200 and an integrated touch module 100 . The display panel 200 has a viewing area. The integrated touch module 100 is provided on the display panel 200 . The touch sensing structure 30 of the integrated touch module 100 substantially overlaps the visible area correspondingly. Specifically, the display panel 200 may be, but is not limited to, a liquid crystal display panel (LCD), an organic electroluminescent display panel, an organic light emitting diode display panel, or a micro light emitting diode display panel (μLED display); in addition, a linear The cover plate 400 is attached to the polarizing layer 10 through optical glue (not shown). The description of the integrated touch module 100 is as discussed above and will not be repeated here.

Finally, the technical features of the present invention and its achievable technical effects are summarized as follows:

1. The average reflectivity of the integrated touch module 100 according to the present invention in the visible light range is less than 6% and the standard deviation is less than 0.4%. Through this, good optical properties can be achieved and an integrated touch that meets actual application requirements can be achieved. Modules and their products.

2. According to the polymer film 20 of the integrated touch module 100 of the present invention, the polymer film 20 can be used directly as a substrate without the need to set up another substrate. The optimal thickness of the polymer film 20 of the present invention is only 17 μm, which means that it can be realized It has a bendable and ultra-thin integrated touch module. Furthermore, the polymer film 20 of the present invention combined with the liquid crystal phase retardation layer 23 has good optical properties and has wide-wavelength phase retardation characteristics, which meets the needs of practical applications.

The implementation of the present invention has been described above through specific embodiments. Those with ordinary skill in the art can easily understand the technical features, advantages, and effects of the present invention from the content disclosed in this specification.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the scope of the present invention. All other equivalent changes or modifications made without departing from the spirit disclosed in the present invention shall be included in the following patent application scope.

100: Integrated touch module

10: Linear polarizing layer

10a: Linear polarizing layer

20:Polymer membrane

20a: Phase delay layer

23: Liquid crystal phase retardation layer

30: Nanosilver wire touch sensing structure

200:Display panel

300:Display device

400:Cover

L: incident light

L ₁ : linearly polarized incident light

L ₂ : linearly polarized incident light

L _cl : Left-handed polarized light L _cr : Right-handed polarized light S1: Upper surface S2: Lower surface

Figure 1 is a schematic diagram of a circular polarizer receiving incident light from the external environment, illustrating the anti-reflection principle; Figure 2 plots the reflectance spectrum curve of the first comparative example versus the reflectance spectrum of the entire wavelength; Figure 3 is a schematic diagram of an integrated touch module according to the first embodiment of the present invention; Figure 4 is a spectral graph of reflectivity and wavelength of the circularly polarizing element according to the first embodiment of the present invention; FIG. 5 is a schematic structural diagram of a display device according to a preferred embodiment of the present invention.

100: Integrated touch module

10: Linear polarizing layer

20:Polymer membrane

23: Liquid crystal phase retardation layer

30:Touch sensing structure

S1: upper surface

S2: Lower surface

Claims (11)

An integrated touch module includes: a nanosilver wire touch sensing structure formed on a polymer film, the polymer film has a phase retardation value between 100nm and 160nm at a wavelength of 550nm; wherein , the polymer film, a liquid crystal phase retardation layer and a linear polarizing layer form a circular polarizing element. The average reflectance of the circular polarizing element in the visible light range is less than 5% and the standard deviation of the reflectance is less than 0.2%. The integrated touch module as described in claim 1, wherein the average reflectivity of the integrated touch module in the visible light range is less than 6% and the standard deviation of the reflectivity is less than 0.4%. The integrated touch module as described in claim 1, wherein the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm is less than 6%, and the average reflection of the circularly polarizing element in the wavelength range of 450nm-500nm The difference between the reflectivity and the reflectance at 550nm wavelength is less than 5%. The integrated touch module of claim 1, wherein the polymer film can withstand the processing temperature of the silver nanowire touch sensing structure. The integrated touch module of claim 4, wherein the glass transition temperature of the polymer film is greater than or equal to the highest process temperature for manufacturing the silver nanowire touch sensing structure on the polymer film. The integrated touch module as described in claim 5, wherein the maximum process temperature of the silver nanowire touch sensing structure is 135-140°C, and the main component of the polymer film is methyl methacrylate ( PMMA), cyclic olefin polymer (COP), polycarbonate (PC), polyethylene terephthalate (PET), colorless polyimide (CPI) or derivatives of the above compounds, and their glass transition temperature Greater than or equal to 135-140℃. The integrated touch module as described in claim 1, wherein the polymer film is a positive dispersion type phase retardation layer with a thickness of about 25 μm; the liquid crystal type phase retardation layer is a positive dispersion type phase retardation layer with a thickness of The optical axis difference between the polymer film and the liquid crystal phase retardation layer is approximately 60 degrees. The integrated touch module of claim 1, wherein the silver nanowire touch sensing structure includes: a silver nanowire electrode layer disposed between the polymer film and the liquid crystal phase retardation layer. . The integrated touch module according to claim 1, wherein the silver nanowire touch sensing structure includes: two silver nanowire electrode layers, the two silver nanowire electrode layers are respectively disposed on the polymer the upper and lower surfaces of the membrane. The integrated touch module as described in claim 1, wherein the reflectance difference between the average reflectance of the circularly polarizing element in the wavelength range of 450nm-500nm and the average reflectance in the wavelength range of 525nm-675nm is less than 10%. A touch display device, including: a display panel having a display area; and an integrated touch module as described in claim 1, disposed on the display panel, wherein the integrated touch module The silver nanowire touch sensing structure overlaps the display area accordingly.

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