KR102283674B1 - Capacitive touch pad - Google Patents

Abstract

The present invention relates to a capacitive touch pad. More specifically, the present invention relates to the capacitive touch pad comprising: a touch part; and an adhesive part formed on one surface of the touch part. The touch part is formed of a conductive composition to not only drive a capacitive touchscreen but also to have excellent touch sensitivity.

Description

Capacitive touch pad {CAPACITIVE TOUCH PAD}

This specification relates to a capacitive touch pad.

Recently, a touch screen has been employed as an input device in various electronic devices such as smart phones, wearable devices, computers, and game machines. Such a touch screen is preferred by users because it can operate an electronic device in an intuitive and simple way.

The type of touch screen is largely divided into a pressure-sensitive touch screen, a capacitive (or capacitive, hereinafter capacitive) touch screen, and an infrared touch screen according to a touch input method. Among them, the capacitive touch screen is a method of determining a touch using a change in an electrical signal. More specifically, a small-sized sensor is attached under a glass plate coated with a conductive compound, and a current continuously flows through the glass plate. The sensor is configured to accurately accumulate charges in the horizontal and vertical directions. When a person's finger touches the touch screen with a conductive finger, some of the electrons flowing near the glass plate move to the body, and the sensor detects the change in electrons and recognizes the touched position. Capacitive touch screens are widely popular because they have high screen clarity, can make the screen sturdy, can be easily operated with fingertips, and are relatively easy to implement compared to other methods.

However, in the case of such a capacitive touch screen, there is a limitation that the touch screen cannot be used because the change in charge is not sufficiently detected when gloves are worn.

Korean Patent Publication No. 10-2017-0034555

In one aspect, the present invention is to provide a capacitive touch pad capable of driving a touch screen.

In one aspect, the present invention is a touch unit; and an adhesive part formed on one surface of the touch part, wherein the touch part provides a capacitive touch pad formed of a conductive composition.

In an exemplary embodiment, the conductive composition may include any one or more of the group consisting of carbon nanotubes, carbon black, and silver.

In an exemplary embodiment, the conductive composition may include 3 to 10% by weight of carbon nanotubes, 20 to 30% by weight of carbon black, and 2 to 10% by weight of silver, based on the total weight of the conductive composition.

In an exemplary embodiment, the conductive composition may further include an antibacterial material.

In an exemplary embodiment, the antibacterial material may include any one or more of the group consisting of phytoncide, oregano extract, thyme extract, and cinnamon extract.

In an exemplary embodiment, the touch unit may be coated with graphene.

In an exemplary embodiment, the adhesive part may be formed of an adhesive polyurethane.

In an exemplary embodiment, the adhesive polyurethane may be formed by polymerization of a polyol and an isocyanate compound.

In an exemplary embodiment, the isocyanate compound is any one of the group consisting of hexa-methylene-diisocyanate, methylene-diisocyanate, toluene-diisocyanate, isoprene-diisocyanate and 4,4'-diphenylmethane diisocyanate. may include more than one.

In one aspect, the capacitive touch pad according to the present invention can drive the capacitive touch screen, and has excellent touch sensitivity so that a desired point can be precisely touched.

In one aspect, the capacitive touch pad according to the present invention has excellent adhesion, so it can be attached to not only clothing including gloves, scarves, and shirts, but also tools such as pens, rulers, and paper, and can be attached and detached multiple times.

Hereinafter, before describing in detail through preferred embodiments of the present invention, terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and meanings consistent with the technical spirit of the present invention and should be interpreted as a concept.

Throughout this specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

In one aspect, the present invention is a touch unit; and an adhesive part formed on one surface of the touch part, wherein the touch part provides a capacitive touch pad formed of a conductive composition.

In one embodiment, the touch unit is formed of a conductive composition to allow current to pass through, and can be operated in contact with a touch screen provided in a smart phone, wearable device, etc., and the touch screen is driven by sensing static electricity. That is, even if the human body does not directly contact the touch screen, it is possible to operate through the touch unit according to an embodiment of the present invention. The touch unit may be formed in various shapes such as a triangle, a rectangle, a pentagon, and a circle.

In one embodiment, the conductive composition is for forming the touch part of the present invention, and may include any one or more of the group consisting of carbon nanotubes, carbon black, and silver. In addition, the conductive composition may further include an adhesive resin and a diluent, but is not limited thereto.

In one embodiment, the content of the carbon nanotubes may be 3 to 10% by weight based on the total weight of the conductive composition. When the content of the carbon nanotube is less than 3 wt%, the electrical conductivity of the touch part is lowered, so that the touch screen cannot be operated sufficiently, and when it is more than 10 wt%, the hardness of the touch part is lowered. Specifically, the content of the carbon nanotubes is 3 wt% or more, 3.5 wt% or more, 4 wt% or more, or 4.5 wt% or more, and 10 wt% or less, 9.5 wt% or less, 9 wt% based on the total weight of the conductive composition or less, 8.5 wt% or less, 8 wt% or less, or 7.5 wt% or less.

In one embodiment, the content of the carbon black may be 20 to 30% by weight based on the total weight of the conductive composition. When the content of carbon black is less than 20% by weight, the electrical conductivity of the touch part is lowered, and when it is more than 30% by weight, carbon black may come off from the touch part. Specifically, the content of the carbon black is 20 wt% or more, 20.5 wt% or more, 21 wt% or more, 21.5 wt% or more, 22 wt% or more, 22.5 wt% or more, or 23 wt% or more, based on the total weight of the conductive composition. , 30 wt% or less, 29.5 wt% or less, 29 wt% or less, 28.5 wt% or less, 28 wt% or less, 27.5 wt% or less, or 27 wt% or less.

In one embodiment, the silver content may be 2 to 10 wt% based on the total weight of the conductive composition. When the silver content is less than 2 wt%, the electrical conductivity of the touch part is lowered, and when the silver content is more than 10 wt%, the hardness of the touch part is reduced. Specifically, the content of silver is 2 wt% or more, 2.5 wt% or more, 3 wt% or more, 3.5 wt% or more, 4 wt% or more, 4.5 wt% or more, or 5 wt% or more, based on the total weight of the conductive composition, and 10 Weight % or less, 9.5 wt% or less, 9 wt% or less, 8.5 wt% or less, 8 wt% or less, 7.5 wt% or less, or 7 wt% or less.

In one embodiment, the adhesive resin serves to form the shape of the touch part by aggregating the conductive material, and may include any one or more from the group consisting of polyethylene, polypropylene, polyethylene oxide, dextrin, and starch. It is not necessarily limited to this.

In one embodiment, the content of the adhesive resin may be 20 to 55% by weight based on the total weight of the conductive composition. When the content of the adhesive resin is less than 20% by weight, the hardness of the touch part is lowered, and when it is more than 55% by weight, the electrical low conductivity of the touch part is deteriorated. Specifically, the content of the adhesive resin is 20 wt% or more, 21 wt% or more, 22 wt% or more, 23 wt% or more, 24 wt% or more, 25 wt% or more, or 26 wt% or more, based on the total weight of the conductive composition. 55 wt% or less, 54 wt% or less, 53 wt% or less, 52 wt% or less, 51 wt% or less, 50 wt% or less, 49 wt% or less, 48 wt% or less, 47 wt% or less, 46 wt% or less or less or 45% by weight or less.

In one embodiment, the diluent serves as a diluent for the adhesive resin to improve the electrical conductivity of the touch part, and a compound having a methyl group, an ethyl group, a propyl group, a butyl group, for example, ethyl carbitol acetate, butyl carbitol acetate and the like.

In one embodiment, the content of the diluent may be 5 to 10% by weight based on the total weight of the conductive composition. When the content of the diluent is less than 5% by weight, there is a problem in that the conductive material such as carbon nanotubes is only partially bonded to the adhesive resin, and when the content of the diluent is more than 10% by weight, the hardness of the touch part is lowered. Specifically, the content of the diluent is 5 wt% or more, 5.5 wt% or more, 6 wt% or more, 6.5 wt% or more, or 7 wt% or more, and 10 wt% or less, 9.5 wt% or less, based on the total weight of the conductive composition; 9 wt% or less, 8.5 wt% or less, or 8 wt% or less.

In one embodiment, the conductive composition may further include an antibacterial material. The antibacterial material may include any one or more of the group consisting of phytoncide, oregao extract, thyme extract, and cinnamon extract.

In one embodiment, the content of the antibacterial material may be 2 to 5% by weight based on the total weight of the conductive composition. If the content of the antibacterial material is less than 2% by weight, the antibacterial effect is not sufficient, and if it is more than 5% by weight, the physical properties of the touch part are deteriorated. Specifically, the content of the antimicrobial material is 2 wt% or more, 2.2 wt% or more, 2.4 wt% or more, 2.6 wt% or more, 2.8 wt% or more, or 3 wt% or more, and 5 wt% or less, based on the total weight of the conductive composition , 4.8 wt% or less, 4.6 wt% or less, 4.4 wt% or less, 4.2 wt% or less, or 4 wt% or less.

In an embodiment, the touch unit may be coated with graphene. Graphene is very thin, light, durable, and has excellent electrical conductivity, thereby increasing the reactivity of the touch pad according to an embodiment of the present invention to the touch screen. As the graphene coating method, a method of coating the touch part by immersing it in a graphene coating solution may be used, or a chemical vapor deposition method using silver included in the touch part as a metal catalyst may be used, but is not limited thereto.

In one embodiment, the adhesive part is formed on one surface of the touch unit, so that the touch pad according to an embodiment of the present invention is not only clothing including gloves, scarves, shirts, pants, etc., but also tools such as pens, rulers, paper, etc. By allowing it to be attached, such an adhesive portion may be formed of an adhesive polyurethane.

In one embodiment, the adhesive polyurethane may be formed by a polymerization reaction of a polyol and an isocyanate compound. The polyol may be a polyol having at least two or more hydroxyl groups, and the isocyanate compound is hexa-methylene-diisocyanate, methylene-diisocyanate, toluene-diisocyanate, isoprene-diisocyanate and 4,4'-diphenylmethane. It may include any one or more of the group consisting of diisocyanate.

In one embodiment, the polyol may be a polyester polyol having a molecular weight of 2500 to 4000. Preferably, the polyol may be a polyester polyol having a molecular weight of 3000 to 3500. The molecular weight may be a number average molecular weight.

In one embodiment, the isocyanate compound may be a mixture of toluene-diisocyanate and 4,4'-diphenylmethane diisocyanate in a ratio of 1:0.5 to 1:2, preferably 1:1.5.

In one embodiment, the content of the polyol may be 48 to 75% by weight based on the amount of the adhesive polyurethane species. Specifically, the content of the polyol is 48 wt% or more, 49 wt% or more, 50 wt% or more, 51 wt% or more, 52 wt% or more, 53 wt% or more, 54 wt% or more, or 55 wt% or more, and 75 wt% or less, 74 wt% or less, 73 wt% or less, 72 wt% or less, 71 wt% or less, 70 wt% or less, 69 wt% or less, or 68 wt% or less.

In one embodiment, the content of the isocyanate compound may be 10 to 20% by weight based on the amount of the adhesive polyurethane species. Specifically, the content of the isocyanate compound is 10 wt% or more, 10.5 wt% or more, 11 wt% or more, 11.5 wt% or more, 12 wt% or more, 12.5 wt% or more, or 13 wt% or more based on the amount of the adhesive polyurethane species. and 20 wt% or less, 19.5 wt% or less, 19 wt% or less, 18.5 wt% or less, 18 wt% or less, 17.5 wt% or less, or 17 wt% or less.

In one embodiment, the polymerization reaction may be carried out by adding a chain extender. The chain extender may include any one or more of the group consisting of ethylene glycol, diethylene glycol, butanediol, hexanediol, hexylene glycol, and trimethylolpropane.

Hereinafter, the configuration and effect of the present invention will be described in more detail by way of examples. However, the following examples are provided for illustrative purposes only to aid understanding of the present invention, and the scope and scope of the present invention are not limited thereto.

[Test Example 1] Touch performance evaluation

Electrostatic pads of Examples 1 to 3 and Comparative Examples 1 to 3 were prepared with the conductive composition of the composition shown in Table 1 below (unit: wt%).

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 carbon nanotubes 3 5 7 5 5 carbon black 30 25 23 25 25 silver 7 4 8 5 5 polyethylene oxide 30 33 30 35 35 45 dextrin 20 20 20 25 25 35 ethyl carbitol acetate 10 10 10 10 10 10 phytoncide 2 Sum 100 100 100 100 100 100

Specifically, an electrostatic pad was prepared by preparing a circular touch part having a diameter of 5 mm and a thickness of 1 mm with the conductive composition of the composition shown in Table 1, and forming an adhesive part with an adhesive polyurethane on one surface thereof. In this way, after attaching the capacitive pads of Examples 1 to 3 and Comparative Examples 1 to 3 to the pen, the touch screen was touched 100 times, and the number of times of touch recognition is shown in Table 2 below.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 touch recognition 97/100 98/100 100/100 89/100 91/100 78/100

[Test Example 2] Adhesion evaluation

Electrostatic pads of Examples 4 to 6 and Comparative Examples 4 to 6 were prepared using the adhesive polyurethane having the composition shown in Table 3 (unit: wt%).

division number average
Molecular Weight Example 4 Example 5 Example 6 Comparative Example 4 Comparative Example 5 Comparative Example 6 polyester polyol 2000 72 3000 72 72 72 4000 72 5000 72 Toluene-diisocyanate 12 8 7 8 8 5 4,4'-diphenylmethane diisocyanate 8 12 13 12 12 15 1,4-butanediol 5 5 5 5 5 5 Reactive Antifoam 3 3 3 3 3 3 Sum 100 100 100 100 100 100

Specifically, according to the composition shown in Table 3, when the polyester polyol is heated to 80° C., 1,4-butanediol, a chain extender, is added, and nitrogen is injected while toluene-diisocyanate and 4,4'-diphenyl Methane diisocyanate was added. Then, an antifoaming agent was added, stirred for 10 minutes, vacuum reduced, and defoamed for 60 minutes to prepare an adhesive polyurethane. Examples 4 to 6 and Comparative Examples 4 to 6 were prepared by forming an adhesive part with the adhesive polyurethane on one surface of the touch part formed with the same composition as in Example 2.

The adhesive strength (tensile shear) of Examples 4 to 6 and Comparative Examples 4 to 6 prepared in this way was measured according to the test method of KS G 9140, and Examples 4 to 6 and Comparative Examples 4 to 6 were applied to ski gloves. The adhesive strength after 10 times of attachment and detachment was measured, and the results are shown in Table 4 below.

Example 4 Example 5 Example 6 Comparative Example 4 Comparative Example 5 Comparative Example 6 Adhesive strength (N/mm ² ) 2.3 2.1 2.4 1.4 3.3 2 Adhesive strength after 10 times of attachment and detachment (N/mm ² ) 2.0 2.0 2.1 1.2 1.5 1.5

The above description of the present invention is for illustration, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a dispersed form, and likewise components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention.

Claims (9)

a touch part coated with graphene; and an adhesive part formed on one surface of the touch part;
The touch part is formed to include a conductive composition and an antibacterial material,
The conductive composition comprises 3 to 10% by weight of carbon nanotubes, 20 to 30% by weight of carbon black, and 2 to 10% by weight of silver (Ag) based on the total weight of the conductive composition,
The antibacterial material consists of 2 to 5% by weight of phytoncide based on the total weight of the conductive composition,
As the adhesive part is formed including an adhesive polyurethane,
The adhesive polyurethane is formed by a polymerization reaction of 48 to 75% by weight of a polyol based on the total weight of the adhesive polyurethane and 10 to 20% by weight of an isocyanate compound based on the total weight of the adhesive polyurethane,
The polyol is a polyester polyol having a molecular weight of 3000 to 3500,
The isocyanate compound is toluene-diisocyanate and 4,4'-diphenylmethane diisocyanate in a ratio of 1: 1.5, characterized in that the mixed, capacitive touchpad. delete delete delete delete delete delete delete delete