Patent Description:
In recent years, with the rapid progress of technology, textiles with diverse functions have been developed to enhance the convenience of human life. For example, electronic components can be attached to textiles, and clothing made from textiles with the attached electronic components can be applied to new fields, such as smart watches, wearable pedometers, smart bracelets, etc. Furthermore, in conjunction with the prevailing trend of smart products nowadays, these electronic devices have also become the mainstream products in the consumer market. On the other hand, as these wearable electronic devices have caused huge repercussions in the consumer market, products combining electronic devices and clothing have also come out one after another.

In <CIT> is disclosed a wearable telescopic conductive cloth comprising a soft rubber layer, a silver glue circuit layer, an auxiliary circuit layer, an insulation protection layer and a waterproof layer sequentially stacked on the surface of the conductive cloth.

<CIT> discloses a paste for forming stretchable conductor, which is capable of forming a wiring line that exhibits good repeated strechability and is obtained by mixing a conductive filler, a polyester elastomer and an organic solvent.

A conductive paste to be coated on an expandable substrate is disclosed in <CIT>, wherein the paste contains an aqueous polyurethane dispersion and conductive particles.

In <CIT> is disclosed a sintering-free type conductive coating used on the surface of a textile, wherein the coating is prepared from nano silver particles, a resin bonding phase, a solvent and an adjuvant.

<CIT> discloses stretchable polymer thick film compositions useful for wearable garments, wherein the polymer thick film may be used in applications where significant stretching is required, particularly on substrates that can be highly elongated such as a thermoplastic polyurethane substrate.

<NPL>, characterized the resistance change of a stretchable silver ink that was screen printed to thermoplastic polyurethane sheets.

Due to the prevalence of sports, related products are booming, and the elasticity of conductive textiles has gradually been taken seriously. However, general conductive textiles often have high relative resistance variation (ΔR/R<NUM>) due to stretching, which will affect the performance of the electronic device. Therefore, how to provide a conductive textile that can solve the above problems has gradually become an important issue for textile industry researchers.

In the light of this, one of the purposes of the present disclosure is to provide a conductive textile that can solve the aforementioned problems.

In order to achieve the above purpose, the present disclosure provides a conductive textile including a base cloth and a conductive film disposed on the base cloth. The conductive film includes a polyurethane resin and a silver-comprising conductor, in which a content of the silver-comprising conductor is <NUM> parts by weight to <NUM> parts by weight, and a content of the polyurethane resin is <NUM> parts by weight to <NUM> parts by weight. The polyurethane resin includes a molecular structure represented by formula (<NUM>),
<CHM>
formula (<NUM>), in which k, n1, n2, n3, n4, n5, n6, m1, and m2 are positive integers, and (k+m1+m2+<NUM>):(n1+n2+n3+n4+m1×n5+m2×n6) is between <NUM>:<NUM> and <NUM>:<NUM>.

In some embodiments of the present disclosure, the silver-comprising conductor includes a flake-shaped silver powder, and a length of a maximum major axis of the flake-shaped silver powder is between <NUM> and <NUM>.

In some embodiments of the present disclosure, the silver-comprising conductor includes a silver nanowire, a wire diameter of the silver nanowire is between <NUM> and <NUM>, and an aspect ratio of the silver nanowire is between <NUM> and <NUM>.

In some embodiments of the present disclosure, a thickness of the conductive film is between <NUM> and <NUM>.

In some embodiments of the present disclosure, the base cloth includes thermoplastic polyurethane, the silver-comprising conductor includes a flake-shaped silver powder, the content of the polyurethane resin is <NUM> parts by weight, a content of the flake-shaped silver powder is <NUM> parts by weight, a length of a maximum major axis of the flake-shaped silver powder is between <NUM> and <NUM>, and a thickness of the conductive film is between <NUM> and <NUM>, when the conductive textile is stretched to <NUM>% of its original length, a relative resistance variation (ΔR/R<NUM>) of the conductive textile is lower than <NUM>%, in which the relative resistance variation is measured by carrying out the standard method of DIN <NUM>-<NUM> on the conductive textile by testing its conductivity with a two-point probe.

The present disclosure provides a fabricating method for a conductive textile, including: providing a base cloth; performing a mixing step to mix a polyurethane resin, a silver-comprising conductor, and an n-propanol, such that a conductive silver paste is obtained, in which a content of the silver-comprising conductor is <NUM> parts by weight to <NUM> parts by weight, and a content of the polyurethane resin is <NUM> parts by weight to <NUM> parts by weight, the polyurethane resin includes a molecular structure represented by formula (<NUM>),
<CHM>
formula (<NUM>), wherein k, n1, n2, n3, n4, n5, n6, m1, and m2 are positive integers, and (k+m1+m2+<NUM>):(n1+n2+n3+n4+m1×n5+m2×n6) is between <NUM>:<NUM> and <NUM>:<NUM>; performing a coating step to coat the conductive silver paste onto the base cloth; and performing a baking step to bake and dry the base cloth undergone the coating step, such that a conductive film is formed on the base cloth.

In some embodiments of the present disclosure, wherein a content of the n-propanol is <NUM> parts by weight to <NUM> parts by weight.

In the aforementioned embodiments of the present disclosure, the conductive textile provided by the present disclosure has low relative resistance variation (ΔR/R<NUM>), so as to be suitable for sportswear. By adjusting the compositions and the composition ratio in the conductive film, the film-forming ability, conductive ability, and relative resistance variation of the conductive film can be improved. In the fabricating method for the conductive textile, the conductive silver paste is prepared by using the n-propanol as a slovent instead of a highly toxic solvent. Therefore, the conductive silver paste prepared by such a fabricating method has good bio-friendliness. In addition, the conductive silver paste prepared in the present disclosure has an appropriate viscosity, so as to facilitate the subsequent processing.

The above is only used to explain the problems to be solved, the technical means to solve the problems, the resulting effect in the present disclosure, etc. More details of the present disclosure will be described in the following embodiments and related drawings.

The present disclosure provides a conductive textile which has low relative resistance variation (ΔR/R<NUM>) and can maintain a good conductive loop when being stretched, so as to be suitable for sportswear. Compared to the conventional techniques, the conductive film of the conductive textile provided by the present disclosure has good elasticity. In addition, the conductive silver paste in the fabricating method also has good bio-friendliness and suitable viscosity, so as to facilitate subsequent processing.

Reference is made to <FIG>, which is a cross-sectional view illustrating a conductive textile <NUM> according to some embodiments of the present disclosure. The conductive textile <NUM> includes a base cloth <NUM> and a conductive film <NUM> disposed on the base cloth <NUM>. In some embodiments, the base cloth <NUM> may be, for example, a knitted fabric, a woven fabric or a non-woven fabric, and the base cloth <NUM> may include polyester, nylon, cotton, polypropylene, polyurethane, or combinations thereof.

The conductive film <NUM> includes a polyurethane resin <NUM> and silver-comprising conductors <NUM>, in which the polyurethane resin <NUM> serve as a carrier for the silver-comprising conductors <NUM>, and the silver-comprising conductors <NUM> serve as a main conductive medium in the conductive film <NUM>, such that the conductive film <NUM> can have elasticity and conductivity at the same time. In some embodiments, a thickness of the conductive film <NUM> is between <NUM> and <NUM>, such that the conductive film <NUM> is suitable for being disposed on the base cloth <NUM> of the conductive textile <NUM> to provide the conductive textile <NUM> with conductivity and low relative resistance variation when being stretched. In some embodiments, when the conductive textile <NUM> is stretched to <NUM>% of its original length, the relative resistance variation (ΔR/R<NUM>) of the conductive textile <NUM> is lower than <NUM>%. Therefore, when the conductive textile <NUM> is stretched, the conductive textile <NUM> can still maintain low relative resistance variation and a good conductive function.

The polyurethane resin <NUM> serves as the carrier for the silver-comprising conductors <NUM> to form the conductive film <NUM>. Since the polyurethane resin <NUM> has good elasticity, the conductive film <NUM> can have good elasticity when the polyurethane resin <NUM> is being used to form the conductive film <NUM>.

In some embodiments, the polyurethane resin <NUM> includes a molecular structure represented by formula (<NUM>), so as to enhance the interpenetrating effect, thereby enhancing the elasticity of the conductive film <NUM>, in which formula (<NUM>) is provided as follows:
<CHM>
formula (<NUM>), in which k, n1, n2, n3, n4, n5, n6, m1, and m2 are positive integers, and (k+m1+m2+<NUM>):(n1+n2+n3+n4+m1×n5+m2× n6) is between <NUM>:<NUM> and <NUM>:<NUM>. When the polyurethane resin <NUM> has the molecular structure represented by the above formula (<NUM>), the silver-comprising conductors <NUM> can be connected in series through the dendritic structure of the polyurethane resin <NUM>, thereby maintaining the conductivity and the low relative resistance variation when the conductive textile <NUM> is being stretched.

In some embodiments, a fabricating method for the polyurethane resin <NUM> may include: mixing a isocyanate and a glycerol to form an intermediate product; and mixing the intermediate product, a polyether polyol, and a catalyst to form the polyurethane resin <NUM>. Specifically, the isocyanate may be, for example, dicyclohexylmethane <NUM>,<NUM>'-diisocyanate (H12MDI); the catalyst may be, for example, dibutyltin dilaurate, dibutyltin diacetate, trifluoromethanesulfonic acid, methanesulfonic acid, diphenyl phosphate, pyridylamine, or other nitrogen heterocyclic ring such as triethylenediamine or N-heterocyclic carbene; and the polyether polyol may be, for example, polytetramethylene ether glycol (PTMEG) with a molecular weight between <NUM> and <NUM>. In addition, the intermediate product includes a molecular structure represented by formula (<NUM>),
<CHM>
in which in formula (<NUM>), m is a positive integer. In some embodiments, a molar ratio of the isocyanate and the polyether polyol used to prepare the polyurethane resin <NUM> may be, for example, between <NUM>:<NUM> and <NUM>:<NUM>, such that the (k+m1+m2+<NUM>):(n1+n2+n3+n4+m1×n5+m2×n6) in formula (<NUM>) can be between <NUM>:<NUM> and <NUM>:<NUM>.

The silver-comprising conductors <NUM> may be uniformly distributed in the polyurethane resin <NUM> to serve as the main conductive medium in the conductive film <NUM>. The silver-comprising conductors <NUM> may include silver metal powder or silver alloy powder. In some embodiments, the silver-comprising conductors <NUM> may include flake-shaped silver powder, in which a length of a maximum major axis of the flake-shaped silver powder is between <NUM> and <NUM>, and an aspect ratio of the flake-shaped silver powder is lower than <NUM>:<NUM>. In other embodiments, the silver-comprising conductors <NUM> include silver nanowire, a wire diameter of the silver nanowire is between <NUM> and <NUM>, and an aspect ratio of the silver nanowire is between <NUM> and <NUM>. Through the above configuration, the dispersion of the silver-comprising conductors <NUM> can be improved, which can further improve the conductivity of the conductive textile <NUM> and reduce the relative resistance variation of the conductive textile <NUM> while stretching. In addition, since the aspect ratio of the silver nanowire is significantly larger, the silver powder and the silver nanowire can be clearly distinguished by their aspect ratio.

In the conductive film <NUM>, a content of the polyurethane resin <NUM> is <NUM> parts by weight is to <NUM> parts by weight, and a content of the silver-comprising conductors <NUM> is <NUM> parts by weight to <NUM> parts by weight. If the content of the silver-comprising conductors <NUM> is lower than <NUM> parts by weight, the conductive ability of the conductive film <NUM> is poor, thereby declining the relative resistance variation of the conductive textile <NUM> while stretching. In detail, since the silver-comprising conductors <NUM> can electrically conduct with each other through physical contact, when the content of the conductive film <NUM> is lower than <NUM> parts by weight, the density of the silver-comprising conductors <NUM> is too low to be effectively in contact, and a current interruption is occurred when the conductive textile <NUM> is being stretched, which in turn declines the relative resistance variation of the conductive textile <NUM>. However, if the content of the silver-comprising conductors <NUM> is higher than <NUM> parts by weight, it is difficult for the silver-comprising conductors <NUM> to be uniformly distributed in the polyurethane resin <NUM>, resulting in a poor film-forming property of the conductive film <NUM>, such that the conductive film <NUM> is difficult to be disposed on the base cloth <NUM>.

<FIG> is a flow chart illustrating a fabricating method <NUM> for a conductive textile according to some embodiments of the present disclosure.

Reference is made to <FIG>. Firstly, in step S210, the base cloth is provided. The types and materials of the base cloth are as described above, which will not be repeated hereinafter.

Next, in step S230, a mixing step is performed to mix the polyurethane resin, the silver-comprising conductors, and the n-propanol, such that a conductive silver paste is obtained. In some embodiments, <NUM> parts by weight to <NUM> parts by weight of the polyurethane resin, <NUM> parts by weight to <NUM> parts by weight of the silver-comprising conductors, and <NUM> parts by weight to <NUM> parts by weight of the n-propanol may be mixed to obtain the conductive silver paste. The types and materials of the silver-comprising conductors are as described above, which will not be repeated hereinafter. In addition, since the n-propanol is used as the solvent, the conductive silver paste of the present disclosure is environmental- and bio-friendly compared to the conventional conductive silver paste, which is prepared by the conventional fabricating process. Moreover, in some embodiments, a viscosity of the conductive silver paste obtained in step S230 may be between <NUM> cP and <NUM> cP, thereby being suitable for subsequent processing such as screen printing.

Next, in step S250, a coating step is performed to coat the conductive silver paste onto the base cloth. In some embodiments, the conductive silver paste may be coated on the base cloth by rod coating or screen printing, but the present disclosure is not limited in this regard.

Finally, in step S270, a baking step is performed to bake and dry the base cloth which has undergone the coating step, such that the conductive film is formed on the base cloth, thereby forming the conductive textile. In some embodiments, a temperature of the baking step may be between <NUM> and <NUM>, but the present disclosure is not limited in this regard.

Accordingly, in steps S210 to S270, since the low-toxicity n-propanol is used as the solvent, the fabricating method for the conductive textile of the present disclosure is environmental- and bio-friendly. In addition, since a specific content of the polyurethane resin, the silver-comprising conductors, and the n-propanol are used to prepare the conductive silver paste, the conductive silver paste has a specific viscosity, and hence the conductive silver paste can be formed on the base cloth by, for example, coating such as screen printing, such that the conductive textile which is suitable for various applications is obtained.

In the following descriptions, features and effects of the present disclosure will be described more specifically with reference to some embodiments and comparative examples. It is noted that without exceeding the scope of the present disclosure, the materials used, their amount and ratio, processing details, processing flow, etc. can be appropriately alternated. Therefore, the present disclosure should not be interpreted restrictively by the embodiments provided below.

In this experiment, the conductive textiles of the embodiments and comparative examples are fabricated by H12MDI and PTMEG with different molar ratios. Each of the conductive textiles is stretched to <NUM>% of its original length, and the standard method of DIN <NUM>-<NUM> is carried out on each of the conductive textiles by testing its conductivity with a two-point probe to measure the relative resistance variation of each of the conductive textiles.

In each of the conductive textiles shown in Table <NUM>, the base cloth is made of thermoplastic polyurethane, the thickness of the conductive film is <NUM>, the conductive film includes <NUM> parts by weight of the polyurethane resin and <NUM> parts by weight of the flake-shaped silver powder, and the length of the maximum major axis of the flake-shaped silver powder is between <NUM> and <NUM>.

As shown in Table <NUM>, the polyurethane resin prepared by H12MDI and PTMEG with different molar ratios affect the relative resistance variation of the conductive textile while stretching. Table <NUM> shows the relative resistance variation of each of the conductive textiles after being stretched to <NUM>% of its original length. It can be seen that, compared to comparative examples <NUM> and <NUM>, embodiments <NUM> to <NUM> maintain low relative resistance variation after being stretched.

In this experiment, the conductive textiles of the embodiments and comparative examples are fabricated by conductive films with different thicknesses. Each of the conductive textiles is stretched to <NUM>% of its original length, and the standard method of DIN <NUM>-<NUM> is carried out on the each of the conductive textiles by testing its conductivity with a two-point probe to measure the relative resistance variation of each of the conductive textiles.

In each of the conductive textiles shown in Table <NUM>, the base cloth is made of thermoplastic polyurethane, the conductive film includes <NUM> parts by weight of the polyurethane resin and <NUM> parts by weight of the flake-shaped silver powder, the polyurethane resin is prepared by H12MDI and PTMEG with a molar ratio of <NUM>:<NUM>, and the length of the maximum major axis of the flake-shaped silver powder is between <NUM> and <NUM>.

As shown in Table <NUM>, the thickness of the conductive film also affects the relative resistance variation of the conductive textile while stretching. It can be seen that, compared to comparative example <NUM>, the thickness range of embodiments <NUM> to <NUM> can let the conductive textile to maintain low relative resistance variation after being stretched.

Claim 1:
A conductive textile characterized by comprising:
a base cloth; and
a conductive film disposed on the base cloth, wherein the conductive film comprises:
a polyurethane resin, wherein the polyurethane resin comprises a molecular structure represented by formula (<NUM>),
<CHM>
formula (<NUM>), wherein k, n1, n2, n3, n4, n5, n6, m1, and m2 are positive integers, and (k+m1+m2+<NUM>):(n1+n2+n3+n4+m1 ×n5+m2×n6) is between <NUM>:<NUM> and <NUM>:<NUM>; and
a silver-comprising conductor, wherein a content of the silver-comprising conductor is <NUM> parts by weight to <NUM> parts by weight, and a content of the polyurethane resin is <NUM> parts by weight to <NUM> parts by weight.