WO2023022428A1

WO2023022428A1 - Heating element film and method for manufacturing same

Info

Publication number: WO2023022428A1
Application number: PCT/KR2022/011916
Authority: WO
Inventors: 이재호; 이정우
Original assignee: 주식회사 커버써먼
Priority date: 2021-08-17
Filing date: 2022-08-10
Publication date: 2023-02-23
Also published as: KR20230026581A

Abstract

According to an embodiment of the present invention, a method for manufacturing a heating element film is provided. The method comprises the steps of: laminating a metal film on an upper portion of a base film; coating a photoresist film on an upper portion of the metal film; exposing at least a part of the photoresist film; developing the photoresist film to expose at least a part of the metal film; and etching at least a part of the exposed metal film to form a predetermined heat emission pattern on the metal film, wherein, when a voltage is applied to the metal film, heat may be emitted along the heat emission pattern.

Description

Heating element film and manufacturing method thereof

The present invention relates to a heating element film and a manufacturing method thereof.

As the demand for imparting various functions to clothes increases, various functional clothes have appeared. For example, by including a heating element in clothing, a heating clothing capable of overcoming cold through a simple operation in winter has been developed. These conventional heating clothing can be largely divided into heating clothing using carbon fiber and heating clothing using conductive ink.

However, in the case of heating clothing using carbon fiber, the heating area is small due to the narrow area of carbon fiber, so there is a problem that it is difficult to generate heat throughout the clothing, and it is very difficult to manufacture carbon fiber itself, so the production cost is excessively increased. It was difficult to mass-produce, and the resistance value of carbon fiber was high, so when the size of the heating element was increased, the heating response speed was slow.

In the case of heating clothing using conductive ink, the disadvantages of heating clothing using carbon fiber are solved to some extent in terms of a large heating area and a fast heating response speed. However, in the case of heating clothing using such conductive ink, a gravure printing method was used in which a mold corresponding to the heating pattern was manufactured, a liquid conductive ink was applied to the mold, the conductive ink was etched, and a film was attached. There was a problem that the process was complicated, raw materials were excessively consumed, and it was difficult to change the heating pattern in various ways. In addition, since the electrical properties of the conductive ink are easily changed when an external impact is applied, the heat generation performance is unstable, and the ink is washed out during washing, so washing is almost impossible.

The present invention is to solve the above problems, and an object of the present invention is to provide a heating element film and a manufacturing method thereof.

The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to an embodiment of the present invention, a method for manufacturing a heating element film is provided. The method may include laminating a metal film on top of a base film; coating a photoresist film on top of the metal film; exposing at least a portion of the photoresist layer to light; exposing at least a portion of the metal film by developing the photoresist layer; and forming a predetermined heating pattern on the metal film by etching at least a portion of the exposed metal film, wherein when a voltage is applied to the metal film, heat may be generated along the heating pattern.

The exposing may include disposing a mask having at least one region penetrating the photoresist layer; and irradiating ultraviolet rays to an upper portion of the photoresist layer on which the mask is disposed.

In addition, the exposing may be performed by removing at least a portion of the photoresist layer by applying a developing solution to the photoresist layer.

The method may further include removing the photoresist film by applying a photoresist removing solvent to the photoresist film after the forming of the heating pattern, wherein the photoresist removing solvent includes acetone, NMP (N-methyl- 2-pyrolidone), ethyl acetate, PGMEA (1-methoxy-2-propyl-acetate), butyl acetate, IPA (isopropyl alcohol), MEK (methylethyl ketone), ethanol, and at least one of methanol.

In addition, the metal film may be made of at least one of copper (Cu), gold (Au), silver (Ag), and aluminum (Al).

In addition, the base film may be made of at least one of polyethylene terephthalate (PET), polyimide (PI), polyurethane (PU), and polycarbonate (PC).

In addition, the thickness of the base film may be 20 to 100 μm.

In addition, the thickness of the metal film may be 10 to 30 μm.

The method may further include laminating an auxiliary film to the base film, wherein the auxiliary film includes at least one of polyethylene terephthalate (PET), polyimide (PI), polyurethane (PU), and polycarbonate (PC). material can be made.

According to an embodiment of the present invention, a method for manufacturing a heating fabric is provided. The method may include manufacturing a heating element film according to the method for manufacturing a heating element film according to an embodiment of the present invention; And it may include the step of laminating the heating element film with at least one base fabric.

A heating element film is provided according to an embodiment of the present invention. The heating element film may include a base film; and a metal film laminated on top of the base film and generating heat when a voltage is applied, wherein at least a portion of the metal film is penetrated to form a predetermined heating pattern.

According to the present invention, since the heating pattern is formed using a metal film having a relatively low resistance value rather than carbon fiber, the heating response speed can be increased while the size of the heating element film is increased, and the production cost is reduced to mass-produce this is possible

In addition, according to the present invention, since the heating pattern is formed using a solid metal film rather than a liquid conductive ink, the process can be simplified, the problem of excessive consumption of raw materials can be solved, and various heating patterns can be easily created. It can be applied, and it can solve the problem that the heating performance changes or the problem that it is impossible to wash.

In addition, according to the present invention, by further bonding the auxiliary film under the base film, it is possible to improve the physical properties of the heating element film.

In addition, according to the present invention, by laminating the heating element film with the base fabric to manufacture the heating fabric, it is possible to add conductivity and heat generating function to the heating element film while maintaining mechanical properties of the base fabric.

In order to more fully understand the drawings cited in the detailed description of the present invention, a brief description of each drawing is provided.

1 is a cross-sectional view of a heating element film according to an embodiment of the present invention.

2 is a plan view of a heating element film according to an embodiment of the present invention.

3 is a cross-sectional view of a heating element film according to an embodiment of the present invention.

4 is a flowchart of a method of manufacturing a heating element film according to an embodiment of the present invention.

5A to 5F are diagrams for explaining the method of FIG. 4 .

6 is a cross-sectional view of a heating fabric according to an embodiment of the present invention.

7 is a flowchart of a method for manufacturing a heating fabric according to an embodiment of the present invention.

Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing an embodiment of the present invention, if it is determined that a detailed description of a related known configuration or function hinders understanding of the embodiment of the present invention, the detailed description will be omitted. In addition, embodiments of the present invention will be described below, but the technical idea of the present invention is not limited or limited thereto and can be modified and implemented in various ways by those skilled in the art. On the other hand, for convenience described below, the directions of up, down, left and right are based on the drawings, and the scope of the present invention is not necessarily limited to the corresponding directions.

Terms used in this specification are used to describe embodiments, and are not intended to limit and/or limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms include or have are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features, numbers, or steps However, it should be understood that it does not preclude the possibility of existence or addition of operations, components, parts, or combinations thereof.

Throughout the specification, when a part is said to be "connected" to another part, this includes not only the case where it is "directly connected" but also the case where it is "indirectly connected" through another component in the middle. . Throughout the specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated. Also, terms such as first, second, A, B, (a), and (b) may be used to describe components of an embodiment of the present invention. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term.

The present invention is supported by the Seoul Metropolitan Government's research project 'Fashion Industry Convergence Technology Commercialization Support Project', and from July 1, 2021 to June 30, 2022 Smart fever control with low-temperature burn prevention function for heating smart clothing This is the result of conducting research on the development of a battery device equipped with the system (Project No. CD210043).

The present invention relates to a heating element film that conducts current and generates heat as voltage is applied. The heating element film may be included in the heating fabric to impart conductivity and heating function to the fabric. It is not limited thereto, and may be used for various purposes according to embodiments.

1 is a cross-sectional view of a heating element film according to an embodiment of the present invention, and FIG. 2 is a plan view of a heating element film according to an embodiment of the present invention.

Referring to FIGS. 1 and 2 , the heating element film 100 may include a base film 110 and a metal film 120 .

The base film 110 may perform functions of maintaining the shape of the metal film 120 , preventing damage, and/or insulating the metal film 120 .

In an embodiment, the base film 110 is polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), linear low density polyethylene (LLDPE), polyimide (PI), polyurethane (PU), At least one of thermoplastic polyurethane (TPU), polycarbonate (PC), acrylic resin and polystyrene (PS) may be used as a material, preferably polyethylene terephthalate (PET), polyimide (PI), polyurethane (PU) ) and polycarbonate (PC). However, it is not limited thereto.

In an embodiment, the base film 110 may have a thickness of 20 μm to 100 μm. When the thickness of the base film 110 is less than 20 μm, the mechanical strength of the heating element film 100 is lowered and the heating element film 100 may be damaged during the lamination and/or etching process of the metal film 120. When the thickness of the base film 110 exceeds 100 μm, the thickness of the heating element film 100 becomes excessively thick, and activity during manufacturing of clothes may deteriorate. However, it is not limited thereto.

The metal film 120 is a thin plate-like sheet made of metal and may be provided on the upper side of the base film 110 . The metal film 120 has conductivity and can conduct current when voltage is applied, and through this, for example, Joule heating can be achieved. That is, since the heating pattern is formed using the metal film 120 having a relatively low resistance value instead of carbon fiber, the heating response speed can be increased while increasing the size of the heating element film 100, and the production cost is reduced. mass production is possible. In addition, since the heating pattern is formed using the solid metal film 120 instead of the liquid conductive ink, the process can be simplified, the problem of excessive consumption of raw materials can be solved, and various heating patterns can be easily applied. It can solve the problem of changing heat generation performance or the problem of not being washable.

In an embodiment, the metal film 120 may form a predetermined heating pattern. The heating patterns may be distributed over at least some areas of the heating element film 100 at regular intervals in order to uniformly generate heat in all areas of the heating element film 100 .

For example, referring to FIG. 2 , in the heating pattern, a stem portion 121 and an edge portion 122 are formed, and at least one first branch portion (from the stem portion 121 toward the edge portion 122) 123) is formed extending, and similarly, at least one second branch portion 124 is formed extending from the edge portion 122 toward the stem portion 121, and the first branch portion 123 and the second branch portion 124 ) may be arranged to intersect with each other at regular intervals. However, it is not limited thereto, and the heating pattern may have various shapes according to embodiments.

In an embodiment, the metal film 120 may be formed to receive a voltage through one region of the heating pattern. For example, the conductive part 125 may be formed to have a predetermined area in one region of the heating pattern. A voltage may be applied by connecting a metallic subsidiary material such as a snap button, a pogo pin, or a magnetic button to the conductive part 125 . As shown in FIG. 2 , the conducting portion 125 may be formed in a rectangular shape at the lower central portion of the heating pattern. However, it is not limited thereto, and depending on the embodiment, the conductive part 125 may have various shapes such as a circle, a triangle, and a polygon.

In an embodiment, the metal film 120 is made of at least one of copper (Cu), gold (Au), silver (Ag), aluminum (Al), iron (Fe), nickel (Ni), and tungsten (W). can be done with Preferably, the metal film 120 may be made of at least one of copper (Cu), gold (Au), silver (Ag), and aluminum (Al). More preferably, the metal film 120 may be made of copper (Cu). However, it is not limited thereto.

In an embodiment, the thickness of the metal film 120 may be 10 μm to 30 μm. When the thickness of the metal film 120 is less than 10 μm, the mechanical strength of the metal film 120 is reduced, and thus the metal film 120 may be damaged during lamination and/or etching. If the thickness of the metal film 120 exceeds 30 μm, the texture of the fabric may be damaged and a foreign body feeling may be felt in the clothes. However, it is not limited thereto.

The heating element film 100 shown in FIGS. 1 and 2 is exemplary, and various configurations may be applied according to an embodiment to which the present invention is applied.

The heating element film 100' of FIG. 3 is described in the same way as the heating element film 100 of FIGS. 1 and 2, and overlapping contents are omitted below.

Referring to FIG. 3 , the heating element film 100 ′ may further include an auxiliary film 140 . The auxiliary film 140 is provided on one surface of the base film 110 to improve overall physical properties of the heating element film 100'. For example, the auxiliary film 140 may improve mechanical strength, tensile strength, and/or flame retardancy of the heating element film 100 . However, it is not limited thereto.

In an embodiment, the auxiliary film 140 is polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), linear low density polyethylene (LLDPE), polyimide (PI), polyurethane (PU), thermoplastic At least one of polyurethane (TPU), polycarbonate (PC), acrylic resin and polystyrene (PS) may be used as a material, preferably polyethylene terephthalate (PET), polyimide (PI), polyurethane (PU) And at least one of polycarbonate (PC) may be used as a material. However, it is not limited thereto.

The heating element film 100' shown in FIG. 3 is exemplary, and various configurations may be applied according to an embodiment to which the present invention is applied. For example, the auxiliary film 140 may additionally/alternatively be positioned on top of the base film 110 and the metal film 120 . However, it is not limited thereto.

4 is a flowchart of a method for manufacturing a heating element film according to an embodiment of the present invention, and FIGS. 5A to 5F are diagrams for explaining the method according to FIG. 4 .

In step S410, the metal film 120 may be laminated on top of the base film 110 (see FIG. 5A). Specifically, step S410 may be performed by laminating the metal film 120 on top of the base film 110 through a laminating process. Laminating refers to a method of compressing a film while passing the film between several heating rollers. For example, the metal film 120 may be laminated while moving at a moving speed of 2 to 5 mm/s under a temperature of 180 to 220° C. and a pressure of 20 bar. However, it is not limited thereto, and according to embodiments, the metal film 120 may be laminated to the base film 110 through various processes.

In step S420, the photoresist film 130 may be coated on top of the metal film 120 (see FIG. 5B). Specifically, step S420 may be performed by coating a liquid photosensitive material on top of the metal film 120 . A photosensitive polymer (photopolymer) is a material that reacts with light and undergoes chemical change. For example, the photosensitive material may change physical properties to react with a developing solution by reacting with ultraviolet rays.

In an embodiment, step S420 may be performed through spin coating, die coating, or laminating. Spin coating is a process of coating a material on a film by rotating the film and distributing the material placed on the substrate to the film through centrifugal force. Die coating is a process of supplying a material to a slot die through a pump and applying a material to a film in a certain thickness while moving the slot die on the film. Laminating is the same as described above. However, it is not limited thereto, and various coating processes may be applied.

In step S430, at least a portion of the photoresist film 130 may be exposed (see FIG. 5C). Specifically, step S430 may be performed by irradiating ultraviolet rays to at least a portion of the photoresist film 130 . Physical properties of the photosensitive material of the photoresist layer 130 may be changed by UV irradiation. That is, only the photoresist film 130 exposed to light (ie, irradiated with ultraviolet light) may selectively react with the developer and be removed. Accordingly, the unexposed portion of the photoresist layer 130 may correspond to the heating pattern of the metal film 120 . However, it is not limited thereto.

In an embodiment, step S430 may include disposing a mask through which one area is formed on the upper part of the photoresist film 130; and irradiating ultraviolet rays to the top of the photoresist film 130 on which the mask is disposed. In this case, the mask may block ultraviolet rays, but the photoresist film 130 may be irradiated with ultraviolet rays through the penetrating area by forming one area through the mask. In addition, non-perforated regions of the mask may correspond to the heating pattern of the metal film 120 . Accordingly, the photoresist film 130 corresponding to the non-perforated portion of the mask remains in step S440, and thus the metal film 120 corresponding to the non-perforated portion of the mask remains in step S450. A heating pattern may be formed in (120). However, it is not limited thereto.

In step S440, at least a portion of the metal film 120 may be exposed to the outside (see FIG. 5D). Specifically, step S440 may be performed by developing the photoresist layer 130 to remove at least a portion of the photoresist layer 130 . For example, as at least a portion of the exposed photoresist layer 130 is removed by a developing solution, the metal film 120 positioned under the removed photoresist layer 130 may be exposed to the outside. Here, the developer may be a solvent capable of selectively removing only the exposed photoresist layer 130 . For example, the developer may include a weakly basic organic solvent, but is not limited thereto.

In an embodiment, step S440 may be performed by immersing the photoresist film 130 in a developing solution or spraying a developing solution onto the photoresist film 130 . However, it is not limited thereto.

In step S450, a heating pattern may be formed on the metal film 120 (see FIG. 5E). Specifically, step S450 may be performed by etching at least a portion of the metal film 120 , and in this case, the metal film 120 to be etched may be the metal film 120 exposed to the outside in step S440 . That is, the metal film 120 that is not removed by etching may form a heating pattern.

* In an embodiment, step S450 may be performed through wet etching. For example, step S450 may be performed by supporting the metal film 120 in an etchant or spraying the etchant onto the metal film 120 . However, it is not limited thereto, and step S450 may be performed through dry etching by plasma according to embodiments.

In an embodiment, the etchant may be a solvent capable of selectively removing only the metal film 120 . For example, the etchant may include an acidic solvent, but is not limited thereto.

In step S460, the photoresist film 130 may be removed (see FIG. 5F). Step S460 may be performed by applying a photoresist removal solvent to the photoresist film 130 . Here, the photoresist removal solvent is a solvent that selectively removes only the photoresist film 130. For example, the photoresist removal solvent is acetone, NMP (N-methyl-2-pyrolidone), ethyl acetate, PGMEA (1- methoxy-2-propyl-acetate), butyl acetate, isopropyl alcohol (IPA), methylethyl ketone (MEK), at least one of ethanol and methanol, preferably acetone, but is not limited thereto.

In an embodiment, the method 400 may further include laminating at least one auxiliary film 140 to a lower portion of the base film 110 . The above step may be performed by laminating the auxiliary film 140 to at least one surface of the base film 110 through a laminating process. However, it is not limited thereto, and various processes may be applied according to embodiments. In addition, the step may be performed after step S460, but is not limited thereto, and may be performed before step S410 or during steps S410 to S460 according to embodiments.

Referring to FIG. 6 , the heating fabric 600 may include a heating element film 610 and

base fabrics

620 and 630 . The heating element film 610 of FIG. 6 may be described in the same way as the heating element films 100 and 100' of FIGS. 1 to 3 .

The

base fabrics

620 and 630 may include a first base fabric 620 laminated to a lower portion of the heating element film 610 and a second base fabric 630 laminated to an upper portion of the heating element film. Through the combination between the

base fabrics

620 and 630 and the heating element film 610, the heating fabric 600 provides the conductivity and heat generating function of the heating element film 610 while maintaining the physical properties of the

base fabrics

620 and 630. can

In an embodiment, the

base fabrics

620 and 630 may shield the heating element film 610 from the outside by being integrated with the heating element film 610 . Accordingly, the heating element film 610 is protected from the outside to improve impact resistance, and when washing the heating fabric 600, mechanical shock is prevented from being applied to the heating element film 610 and the action of moisture can be minimized. there is.

In an embodiment, the

base fabrics

620 and 630 may be polymer friendly fabrics. At this time, the polymer-friendly fabric may be formed by laminating a thermoplastic polymer film on one side of a woven or non-woven fabric. For example, a thermosetting adhesive is coated on one side of the thermoplastic polymer film, and the thermoplastic polymer film is laminated on top of the woven or non-woven fabric so that the coated adhesive is positioned between the woven or non-woven fabric and the thermoplastic polymer film, and then The adhesive may be aged for a certain period of time, and then a base fabric may be formed by thermally curing the adhesive in a laminating or hot press process. Accordingly, the

base fabrics

620 and 630 are more closely integrated with the heating element film 610, and the heating element film 610 can be stably protected from external moisture.

Depending on the embodiment, the first base fabric 620 and the second base fabric 630 may have the same or different materials.

The heating fabric shown in FIG. 6 is exemplary, and various configurations may be applied according to an embodiment to which the present invention is applied. For example, only one of the first base fabric 620 and the second base fabric 630 may be laminated to the heating element film 610 .

The method 700 includes manufacturing a heating element film (S710); And it may include a step (S720) of laminating the heating element film with the base fabric.

Step S710 may be described in the same way as the method 400 of FIG. 4, and redundant descriptions will be omitted below.

In step S720, the heating element film 610 is disposed between the first base fabric 620 and the second base fabric 630, and the heating element film 610 is formed through a hot press or laminating process. The heating element film 610 may be laminated between the

base fabrics

620 and 630 by compressing the base fabrics 62 and 630 . Hot press is a process of placing the

base fabrics

620 and 630 and the heating element film 610 between heating plates and then compressing them. For example, the hot press may be performed by compressing the

base fabrics

620 and 630 and the heating element film 610 for about 1 minute at a temperature of 180 to 220° C. and a pressure of 20 bar. A laminating process may be the same as described above. However, the laminating process of the heating element film 610 and the

base fabrics

620 and 630 is not limited thereto, and various processes may be applied according to embodiments.

As described above, the optimum embodiment has been disclosed in the drawings and specifications. Although specific terms have been used herein, they are only used for the purpose of describing the present invention and are not used to limit the scope of the present invention described in the claims or defining the meaning. Therefore, those of ordinary skill in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical scope of protection of the present invention should be determined by the technical spirit of the appended claims.

Claims

As a method of manufacturing a heating element film

laminating a metal film on top of the base film;

coating a photoresist film on top of the metal film;

exposing at least a portion of the photoresist layer to light;

exposing at least a portion of the metal film by developing the photoresist layer; and

Etching at least a portion of the exposed metal film to form a predetermined heating pattern on the metal film;

A method of generating heat along the heating pattern when a voltage is applied to the metal film.
According to claim 1,

The exposing may include disposing a mask having at least one region penetrating through the photoresist layer; and irradiating ultraviolet light onto the photoresist film on which the mask is disposed.
According to claim 1,

The exposing step is performed by removing at least a portion of the photoresist film by applying a developing solution to the photoresist film.
According to claim 1,

The step of removing the photoresist film by applying a photoresist removal solvent to the photoresist film after the step of forming the heating pattern,

The photoresist removal solvent is acetone, NMP (N-methyl-2-pyrolidone), ethyl acetate, PGMEA (1-methoxy-2-propyl-acetate), butyl acetate, IPA (isopropyl alcohol), MEK (methylethyl ketone) , A method comprising at least one of ethanol and methanol.
According to claim 1,

The metal film is made of at least one of copper (Cu), gold (Au), silver (Ag) and aluminum (Al) as a material.
According to claim 1,

The base film is made of at least one of polyethylene terephthalate (PET), polyimide (PI), polyurethane (PU) and polycarbonate (PC) as a material.
According to claim 1,

The thickness of the base film is 20 to 100 μm, the method.
According to claim 1,

The thickness of the metal film is 10 to 30 μm, the method.
According to claim 1,

Further comprising laminating an auxiliary film to the base film,

The auxiliary film is made of at least one of polyethylene terephthalate (PET), polyimide (PI), polyurethane (PU), and polycarbonate (PC) as a material.
As a method of manufacturing a heating fabric,

Manufacturing a heating element film by the method of any one of claims 1 to 9; and

Comprising the step of laminating the heating element film with at least one base fabric, method.
As a heating element film,

base film; and

A metal film laminated on top of the base film and generating heat when voltage is applied,

The heating element film, wherein at least a portion of the metal film is penetrated to form a predetermined heating pattern.