WO2024025065A1 - Heating cable - Google Patents

Abstract

The present invention relates to a heating cable comprising a metal-coated carbon fiber bundle, a first heat-resistant resin layer, a metal braided layer, and a second heat-resistant resin layer, which are disposed sequentially from the inside, wherein the heating cable has a density of 1.8 to 3.0 g/㎤ on the basis of the metal-coated carbon fiber bundle of 12,000 monofilaments.

Description

heating cable

The present invention relates to a heating cable.

As environmental pollution and the smart era change, metal heating wires used in various household products such as electronic products, heating products, household items, medical supplies, beauty products, and functional clothing that require quick temperature response along with heating function can be replaced. There is a need to prevent environmental pollution and develop highly efficient products for industrial temperature maintenance devices at relatively low temperatures below 300℃. In particular, the need for high-efficiency heating cable products is emerging to increase the efficiency of heating for eco-friendly vehicles such as electric vehicles and various batteries such as fuel cells and hydrogen electricity.

In addition to general metal cables, carbon fiber cables can manufacture high-strength cables using the high tensile strength of carbon fiber, and are manufactured as heat-resistant cables of the same volume compared to existing metal cables, making it possible to manufacture lightweight and highly flexible cables, unlike metal wires. Carbon fiber wires have been developed and are being applied to industrial fields as heating cables due to their advantage in that they can be used as heating cables.

To date, these heat-generating products have been manufactured using copper wire, nichrome wire, carbon fiber, carbon nanotube (CNT), ceramic powder, etc., to produce a suspension to maintain a constant electrical resistance through appropriate mixing and dispersion, and then coating it on polymer fiber or carbon fiber. A common method is to manufacture heat-generating products by molding mixed powder materials.

Since the above products have high power consumption and are difficult to manufacture evenly by mixing and dispersing raw materials, local overheating may occur and there is an inherent risk of short circuit and fire.

Accordingly, unlike the above-mentioned heating products, heating cables are manufactured and used using carbon fiber as a heating conductor, but due to the high resistance of carbon fiber, it is difficult to maintain a constant temperature below 200℃ due to the high heating temperature in a short period of time, and it is difficult to maintain a constant temperature below 200℃ due to the high resistance of carbon fiber. Likewise, this product has a very high risk of disconnection and fire due to a rapid increase in the resistance of the conductor and grounding part of the wire, and long-term durability issues are becoming a serious issue.

Meanwhile, Republic of Korea Patent Publication No. 10-2017-0030126 is presented as a similar prior document regarding this.

In order to solve the above problems, the purpose of the present invention is to provide a heating cable that has a faster response speed compared to existing metal heating cables, can be driven with low power, and has low power consumption.

In addition, the purpose is to provide a heating cable that can maintain a constant temperature below 200℃, is highly durable, and has a very low risk of safety accidents such as fire, wire shorting, and short circuit.

However, the above object is illustrative, and the technical idea of the present invention is not limited thereto.

One aspect of the present invention for achieving the above object is a heating cable sequentially including a metal-coated carbon fiber bundle, a first heat-resistant resin layer, a metal braided layer, and a second heat-resistant resin layer from the inside, wherein the heating cable is mono. It relates to a heating cable, characterized in that the density is 1.8 to 3.5 g/cm3 based on a metal-coated carbon fiber bundle of 12,000 filaments.

In the above aspect, the heating cable may have an electrical resistance of 0.5 to 5 Ω/m.

In one aspect, the heating cable may have an electrical conductivity of 0.1×10 ⁴ to 5.0×10 ⁴ S/cm.

In the above aspect, the heating cable may have a heat capacity of 1 to 3 J/°C.

In the above aspect, the heating cable may have a specific heat of 1 J/g·°C or less.

In the above aspect, the heating cable may have a tensile strength of 100 N or more.

In one aspect, the metal-coated carbon fiber bundle may have 100 to 12,000 monofilament strands.

In the above aspect, the metal-coated carbon fiber bundle may be carbon fiber coated with a first metal and a second metal, the first metal may be nickel or copper, and the second metal may be nickel.

In the above aspect, the first heat-resistant resin layer and the second heat-resistant resin layer are independently made of polyamide (PA), polyethylene (PE), polypropylene (PP), acrylonitrile butadiene styrene (ABS), and polycarbonate. (PC), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polystyrene (PS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), acrylic Nitrile-styrene copolymer resin (SAN), acrylonitrile-styrene-acrylate copolymer resin (ASA), polyphenylene ether (PPE), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK). thermoplastic resin; and rubber resins such as natural rubber, ethylene-propylene-diene monomer (EPDM), styrene butadiene, ethylene propylene, chloroprene, hypalon, silicone, and ethylene vinyl acetate.

In the above aspect, the metal-coated carbon fiber bundle may further include glass fibers surrounding the metal-coated carbon fiber bundle at a predetermined angle along the outer peripheral surface of the metal-coated carbon fiber bundle.

In the above aspect, the angle may be 30 to 60° based on the longitudinal axis of the metal-coated carbon fiber bundle.

In the above aspect, the heating cable may satisfy the following relational expression 1.

[Relationship 1]

│D ₀ -D ₉₀ │/D ₀ × 100 ≤ 10

(In the above equation 1, D ₀ and D ₉₀ are the cross-sectional diameters of the heating cable, respectively, D ₀ is the cross-sectional diameter in one direction (μm), and D ₉₀ is the cross-sectional diameter in the vertical direction in one direction (μm).)

The heating cable according to the present invention has the advantage of having a faster response speed compared to existing metal heating cables, being able to operate at low power, and having low power consumption. In addition, it can maintain a constant temperature below 200℃, has high durability, and the risk of safety accidents such as fire, wire shorting, and short circuit can be very low.

1 is an exemplary diagram of a heating cable according to an example of the present invention.

Figure 2 is an actual photograph of a heating cable manufactured with 3,000 strands of metal-coated carbon fiber (3K MCF) and 12K MCF, respectively, according to an example of the present invention.

Figure 3 is an exemplary diagram of a metal-coated carbon fiber wrapped with glass fiber according to the present invention.

Figure 4 is an optical microscope image of a cross section of a heating cable manufactured according to Example 5.

Hereinafter, the heating cable according to the present invention will be described in detail. The drawings introduced below are provided as examples so that the idea of the present invention can be sufficiently conveyed to those skilled in the art. Accordingly, the present invention is not limited to the drawings presented below and may be embodied in other forms, and the drawings presented below may be exaggerated to clarify the spirit of the present invention. At this time, if there is no other definition in the technical and scientific terms used, they have the meaning commonly understood by those skilled in the art to which this invention pertains, and the gist of the present invention is summarized in the following description and attached drawings. Descriptions of known functions and configurations that may be unnecessarily obscure are omitted.

One aspect of the present invention relates to a heating cable sequentially including a metal-coated carbon fiber bundle, a first heat-resistant resin layer, a metal braid layer, and a second heat-resistant resin layer from the inside, wherein the heating cable consists of 12,000 strands of monofilament. Based on the metal-coated carbon fiber bundle, it can be characterized as having a density of 1.8 to 3.5 g/cm3, an electrical resistance of 0.5 to 5 Ω/m, and an electrical conductivity of 0.1×10 ⁴ to 5.0×10 ⁴ S/cm. there is.

More preferably, the heating cable has a density of 2.0 to 3.0 g/cm3, an electrical resistance of 0.8 to 3 Ω/m, and an electrical conductivity of ^0.5 It may be 4.0×10 ⁴ S/cm, and more preferably, the density is 2.2 to 2.8 g/cm3, the electrical resistance is 0.8 to 2 Ω/m, and the electrical conductivity is 1.0×10 ⁴ to 3.0×10 ⁴ S/. It may be ㎝.

In addition, in order to secure better response speed and lower power consumption, the heating cable may have a heat capacity of 1 to 3 J/°C, a specific heat of 1 J/g·°C or less, and more preferably, a heat capacity of 1.3 to 1.3 J/°C. 2.7 J/°C, the specific heat may be 0.6 to 1 J/g·°C, and more preferably, the heat capacity may be 1.5 to 2.3 J/°C and the specific heat may be 0.7 to 0.85 J/g·°C. At this time, the specific heat may be a value measured through DSC (differential scanning calorimetry) and may mean a value at 50°C.

Furthermore, the heating cable according to an example of the present invention may have excellent mechanical properties. Specifically, for example, the tensile strength may be 100 N or more, and there may be no breakage or change in resistance even after repeated bending tests of more than 100,000 times. there is. More preferably, the heating cable has a tensile strength of 130 N or more, and can be subjected to repeated bending tests of more than 150,000 times without disconnection or change in resistance. Even better, the tensile strength of the cable is more than 150 N, and can be subjected to repeated bending tests of more than 180,000 times. Even if you do this, there may be no disconnection or change in resistance. At this time, the upper limit of the tensile strength is not particularly limited, but may be, for example, 250 N. The number of repeated bending tests is also not particularly limited, but may be, for example, 500,000 times.

As such, the heating cable according to the present invention has excellent electrical and mechanical properties, so it has the advantage of having a faster response speed compared to existing metal heating cables, being able to be driven with low power, and having low power consumption. In addition, it can maintain a constant temperature below 200℃, has high durability, and the risk of safety accidents such as fire, wire shorting, and short circuit can be very low.

Hereinafter, a heating cable according to an example of the present invention will be described in more detail.

Referring to Figure 1, the heating cable according to the present invention may sequentially include a metal-coated carbon fiber bundle (MCF), a first heat-resistant resin layer, a metal braided layer, and a second heat-resistant resin layer from the inside.

In one example of the present invention, the metal-coated carbon fiber bundle may have 100 to 12,000 monofilament strands, preferably 1K (1,000 monofilament strands), 3K (3,000 monofilament strands), or 6K (6,000 monofilament strands). It may be a bundle of metal-coated carbon fibers of 12K (12,000 strands of monofilament), and more preferably, a bundle of metal-coated carbon fibers of 3K (3,000 strands of monofilament) to 12K (12,000 strands of monofilament).

Metal-coated carbon fiber can be used without limitation as long as it is carbon fiber coated with metal on the outer diameter of the carbon fiber through a plating process. However, in order to satisfy the heat generation characteristics and mechanical strength to be manufactured in the present invention, electroless plating and electrolytic plating are used. It is desirable to use carbon fiber double coated with metal. Specifically, for example, the metal-coated carbon fiber bundle may be carbon fiber coated with a first metal and a second metal. More specifically, the metal-coated carbon is electroless plated with nickel or copper and then electrolytically plated with nickel. It may be a fiber, but is not necessarily limited thereto. In addition, the thickness of the metal coating produced by the plating may be 50 to 500 nm, and more preferably 100 to 300 nm. The electrical resistance of the metal-coated carbon fiber may vary depending on the thickness of the metal coating, and a desirable electrical resistance may be 0.1 to 10 Ω/m, but is not limited thereto.

Preferably, the metal-coated carbon fiber bundle may further include glass fibers surrounding the metal-coated carbon fiber bundle at a predetermined angle along the outer peripheral surface of the metal-coated carbon fiber bundle, as shown in FIG. 2.

As a specific example, the angle may be 30 to 60°, more preferably 40 to 60°, and even more preferably 50 to 60° with respect to the longitudinal axis of the metal-coated carbon fiber bundle. In this range, it is good to keep the diameter and center point of the metal-coated carbon fiber bundle more constant when manufacturing a heating cable.

Preferably, the heating cable using a bundle of metal-coated carbon fibers wrapped with glass fibers may satisfy the following relational expression 1.

[Relationship 1]

│D ₀ -D ₉₀ │/D ₀ × 100 ≤ 10

(In the above relational equation 1, D ₀ and D ₉₀ are the cross-sectional diameters of the heating cable, respectively, D ₀ is the cross-sectional diameter in one direction (μm), and D ₉₀ is the cross-sectional diameter in the vertical direction in one direction (μm).)

In other words, the heating cable according to the present invention may have a concentric structure in which the metal-coated carbon fiber bundle is not oriented in a specific direction and the diameter and center point are kept constant, and through this, heat generation at the target level can be precisely controlled. . More preferably, │D ₀ -D ₉₀ │/D ₀ × 100 may be 5 or less, more preferably 3 or less, and in this case, the lower limit may be 0. On the other hand, if the shape of the metal-coated carbon fiber bundle does not have a concentric structure and is severely distorted, the degree of heat generation may vary in each section of the heating cable, which is not good.

At this time, the glass fiber is literally a material made by pulling glass thin and long like a fiber, and the diameter of the glass fiber may be 1 to 20 ㎛, more preferably 3 to 15 ㎛, but is not necessarily limited thereto.

In addition, the glass fiber may be one strand or a plurality of two or more strands, and preferably 3 to 20 strands of glass fiber are used to maintain the diameter and center point of the metal-coated carbon fiber bundle more consistently when manufacturing the heating cable. It's nice to be able to do it.

Such a metal-coated carbon fiber bundle wrapped with glass fibers includes the following steps: a) preparing a metal-coated carbon fiber bundle; and b) wrapping glass fibers at a predetermined angle along the outer peripheral surface of the metal-coated carbon fiber bundle.

First, step a) preparing a metal-coated carbon fiber bundle can be performed.

As described above, the metal-coated carbon fiber bundle according to an example of the present invention can be used without limitation as long as it is a carbon fiber coated with metal on the outer diameter of the carbon fiber through a plating process, but the heat generating properties to be manufactured in the present invention In order to satisfy the mechanical strength, it is preferable to use carbon fiber double coated with metal through electroless plating and electrolytic plating.

As a specific example, step a) includes a-1) electroless plating carbon fiber with a first metal; and a-2) electroplating the electroless plated carbon fiber with a second metal.

The types of the first metal and the second metal may be the same or different, and preferably the first metal may be nickel or copper, and the second metal may be nickel. The electroless and electrolytic process of the present invention can be performed through the method presented in Domestic Patent No. 10-1427309, but is not limited thereto.

The step a-1) may be performed by passing the carbon fiber through an electroless plating solution containing pure water, a first metal salt, a complexing agent, a reducing agent, a stabilizer, and a pH adjuster, and the step a-2) may be It can be performed continuously following step a-1) by applying a constant voltage (CV) of 5 to 15 V using a second metal salt and a pH buffer, but is not limited to the above method.

Before steps a-1) and a-2), (i) degreasing and softening the carbon fibers by passing them through an aqueous solution containing a surfactant, an organic solvent, and a non-ionic surfactant; (ii) The carbon fiber resulting from step (i) is dissolved in an aqueous solution containing sodium bisulfite (NaHSO ₃ ), sulfuric acid (H ₂ SO ₄ ), ammonium persulfate ((NH ₄ ) ₂ S ₂ O ₈ ), and pure water. performing an etching process to neutralize, clean, and condition the skin; (iii) passing the carbon fiber resulting from step (ii) through a PdCl ₂ aqueous solution to perform a sensitizing process; and (iv) performing an activating process by passing the carbon fiber resulting from step (iii) through an aqueous solution of sulfuric acid (H ₂ SO ₄ ). The pre-treated carbon fiber can be used through a pre-treatment process including. However, it is not limited to this.

The thickness of the metal coating produced by the plating may be 50 to 500 nm, and more preferably 100 to 300 nm. The electrical resistance of the metal-coated carbon fiber may vary depending on the thickness of the metal coating, and a desirable electrical resistance may be 0.1 to 10 Ω/m, but is not limited thereto.

In this way, when the metal-coated carbon fiber bundle is prepared, step b) wrapping the glass fiber at a predetermined angle along the outer peripheral surface of the metal-coated carbon fiber bundle can be performed.

At this time, the angle of step b) may be 30 to 60°, more preferably 40 to 60°, and even more preferably 50 to 60° with respect to the longitudinal axis of the metal-coated carbon fiber bundle. Additionally, the distance may be the distance between the centers of the glass fibers spaced apart from the glass fibers, and may be specifically, for example, 50 to 300 ㎛. In this range, it is good to keep the diameter and center point of the metal-coated carbon fiber bundle more constant when manufacturing a heating cable.

In addition, step b) can be performed by applying a tension of 5 to 10 N/tex to the metal-coated carbon fiber bundle. In this range, when performing step b), no bending strain is applied to the metal-coated carbon fiber bundle, preventing damage to the conductor, and the diameter and center point of the metal-coated carbon fiber bundle can be kept more constant. On the other hand, if the tension is less than 5 N/tex, the center point of the heating wire may deviate excessively from the concentric point, and if it exceeds 10 N/tex, the fibers of the metal-coated carbon fiber bundle may be broken due to friction between the metal-coated carbon fiber bundle and the glass fiber. This is not good because the conductor resistance may increase due to (micro-disconnection) or damage to the metal coating layer.

In addition, step b) may wrap the glass fiber at a rotation speed of 50 to 300 cycles/min, and more preferably, the glass fiber may be wrapped at a rotation speed of 100 to 200 cycles/min. In this range, damage may not occur to the metal-coated carbon fiber bundle.

Next, the first heat-resistant resin layer and the second heat-resistant resin layer according to an example of the present invention can be used without particular limitations as long as they are materials having insulation and heat resistance. Specifically, for example, the first heat-resistant resin layer and The second heat-resistant resin layer is independently made of polyamide (PA), polyethylene (PE), polypropylene (PP), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyvinyl chloride (PVC), and polyvinyl. Alcohol (PVA), polystyrene (PS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), acrylonitrile-styrene copolymer resin (SAN), acrylonitrile -Thermoplastic resins such as styrene-acrylate copolymer resin (ASA), polyphenylene ether (PPE), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK); and rubber resins such as natural rubber, ethylene-propylene-diene monomer (EPDM), styrene butadiene, ethylene propylene, chloroprene, hypalon, silicone, and ethylene vinyl acetate.

The metal braided layer according to an example of the present invention is intended to reinforce the shear force of the metal-coated carbon fiber bundle and protect the conductor from external shock, and may be braided with metal wires such as copper, stainless steel, or tin-plated wire.

Such a heating cable includes the following steps: A) manufacturing a metal-coated carbon fiber bundle; B) manufacturing a cable wire by coating the metal-coated carbon fiber bundle with a first heat-resistant resin through a first sheath process; C) braiding the cable wire into a metal wire through a braiding process; and D) manufacturing a heating cable by coating the braided cable wire with a second heat-resistant resin through a secondary sheath process.

If necessary, if the desired resistance per unit length cannot be manufactured, a twisting process can be performed in which insulated cable conductors are twisted into two or more strands to manufacture a cable bundle.

Hereinafter, the heating cable according to the present invention will be described in more detail through examples. However, the following examples are only a reference for explaining the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms.

Additionally, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. The terminology used in the description herein is merely to effectively describe particular embodiments and is not intended to limit the invention. Additionally, the unit of additives not specifically described in the specification may be weight percent.

[Example 1]

Using 12,000 (12K) strands of carbon fiber, a nickel-coated carbon fiber bundle (nickel coating layer thickness 300 nm, MCF) was manufactured using the metal-plated carbon fiber manufacturing method according to Patent No. 10-1427309.

While applying a tension of 1 N/tex to the nickel-coated carbon fiber bundle, glass fibers (20 strands, diameter 5 ㎛) were wound around the outer circumferential surface of MCF1 at a rotation speed of 100 cycles/min. At this time, the length of the metal-coated carbon fiber bundle was Metal-coated carbon fiber was manufactured by adjusting the angle to be 30° relative to the direction axis.

Afterwards, polyamide 6 (PA6) resin (density 1.14 g/cm3, melting point 220℃, tensile strength 83 MPa, Izod impact strength 7.5 Kgf·cm/cm, heat distortion temperature 65℃) was extruded onto the metal-coated carbon fiber bundle. After covering it, copper wire was braided around the outer diameter, and the PA6 resin was extruded and covered again to produce a heating cable about 1.8 m long.

[Examples 2 to 7]

As shown in Table 1 below, a heating cable was manufactured by performing all processes in the same manner as in Example 1 except that the angle of the glass fiber was adjusted differently.

[Examples 8 to 11]

As shown in Table 1 below, a heating cable was manufactured by performing all processes in the same manner as in Example 5, except that the tension applied to the nickel-coated carbon fiber substrate was adjusted differently.

[Example 12]

After preparing a nickel-coated carbon fiber base (nickel coating layer thickness 300 nm) in the same manner as in Example 1, a heating cable was manufactured without winding glass fiber.

[Comparative Example 1]

A heating cable was manufactured by performing all processes in the same manner as in Example 5, except for using a bundle of carbon fiber (12K, CF) that was not coated with metal.

[Comparative Example 2]

A heating cable was manufactured by performing all processes in the same manner as in Example 12, except that copper alloy wire was used instead of MCF.

	monofilament strand count	Angle (°)	tension (N/tex)
Example 1	12K	30	5
Example 2	12K	40	5
Example 3	12K	50	5
Example 4	12K	53	5
Example 5	12K	57	5
Example 6	12K	60	5
Example 7	12K	65	5
Example 8	12K	57	One
Example 9	12K	57	3
Example 10	12K	57	10
Example 11	12K	57	15
Example 12	12K	-	-
Comparative Example 1	12K(CF)	57	5
Comparative Example 2	Cu alloy fiber	-	-

[Characteristics Evaluation]

1) Measure the diameter in one direction (D _0, ㎛) and the fiber diameter (D ₉₀ , ㎛) in the vertical direction in one direction of the heating cables of Examples 1 to 12 manufactured above, respectively, and calculate the difference ratio (%) according to equation 1 ) was calculated, and the electrical resistance (Ω/m) of each heating cable was measured and shown in Table 2 below.

	Heating cable diameter		difference rate (%)	electrical resistance (Ω/m)
	D 0 (㎜)	D 90 (㎜)
Example 1	2.112	1.906	9.75	1.53
Example 2	2.105	1.936	8.03	1.50
Example 3	1.96	1.864	4.90	1.58
Example 4	2.078	2.002	3.66	1.57
Example 5	1.932	1.905	1.40	1.55
Example 6	1.934	1.859	3.88	1.58
Example 7	2.115	1.896	10.35	1.62
Example 8	2.006	1.854	7.58	1.61
Example 9	1.991	1.881	5.52	1.59
Example 10	2.013	1.978	1.74	1.56
Example 11	1.985	1.902	4.18	1.65
Example 12	2.043	1.807	11.55	1.66
Comparative Example 1	-	-	-	35
Comparative Example 2	-	-	-	0.347

2) The density (g/cm3), specific heat (J/g·°C), and electrical conductivity (S/cm) of the heating cables manufactured in Example 5, Comparative Example 1, and Comparative Example 2 were measured, respectively, and the heat capacity ( J/°C) was calculated as the volume × specific heat × density of the specimen and is shown in Table 3 below. At this time, the specific heat was expressed as the specific heat at 50°C in the DSC data.

	density (g/㎤)	electrical conductivity (×10 4 S/cm)	specific heat (J/g·℃)	heat capacity (J/℃)
Example 5	2.50	1.3	0.786	1.975
Comparative Example 1	1.77	0.063	1.11	1.998
Comparative Example 2	8.96	5.524	0.57	5.107

3) Durability and safety tests were conducted using the heating cables of Example 5 and Comparative Example 2 prepared above. The tensile strength was tested based on the MS912-02 automotive hot wire measurement standard, and the repeated bending test was tested based on KS C IEC 60068-2-1: 2010 Environmental Testing - Part 2-1: Test A: Cold Resistance Test. As a result, the heating cable of Example 5 showed excellent strength of 199 N, and there was no breakage or change in resistance even after 180,000 evaluations during repeated bending tests.

On the other hand, in the case of the copper heating cable of Comparative Example 2, the tensile strength was 93 N, which was significantly lower than that of the present invention, and there was a problem of wire breakage occurring after 90,000 bending tests.

When such a disconnection occurs, a fire may occur in the disconnected part of the metal heating cable due to the bottleneck phenomenon. However, the MCF heating cable according to the present invention is not only more resistant to heat, but is manufactured in a bundle of about 12,000 strands, so even if a portion of the cable is disconnected, a fire may occur. It has the advantage of being safer as it does not connect.

4) Power consumption was compared using the heating cables of Example 5 and Comparative Example 2 manufactured above.

As a result, the MCF heating cable according to the present invention has a time to reach the target temperature of 90°C in 284 seconds, while the copper alloy heating cable takes 780 seconds, confirming that the MCF heating cable of the present invention has a response speed that is more than twice as fast. I was able to.

In addition, when the heater is operated by NTC (Negative Temperature Coefficient thermistor) control at a target set temperature of 90°C, the power off time is long due to the fast response speed of the MCF, so Example 5 is about 64.4 W, Comparative Example 2 is about 74.6 W, confirming that power consumption can be reduced.

Although the present invention has been described through specific details and limited examples as described above, these are provided only to facilitate a more general understanding of the present invention, and the present invention is not limited to the above-mentioned examples, and the present invention belongs to Those skilled in the art can make various modifications and variations from this description.

Accordingly, the spirit of the present invention should not be limited to the described embodiments, and the scope of the patent claims described below as well as all modifications that are equivalent or equivalent to the scope of this patent claim shall fall within the scope of the spirit of the present invention. .

Claims (14)

1. A heating cable sequentially including a metal-coated carbon fiber bundle, a first heat-resistant resin layer, a metal braid layer, and a second heat-resistant resin layer from the inside,

   The heating cable is characterized in that the heating cable has a density of 1.8 to 3.5 g/cm3.
2. According to clause 1,

   The heating cable is a heating cable with an electrical resistance of 0.5 to 5 Ω/m.
3. According to clause 1,

   The heating cable has an electrical conductivity of 0.1×10 ⁴ to 5.0×10 ⁴ S/cm.
4. According to clause 1,

   The heating cable is a heating cable having a heat capacity of 1 to 3 J/℃.
5. According to clause 1,

   The heating cable is a heating cable with a specific heat of 1 J/g·°C or less.
6. According to clause 1,

   The heating cable is a heating cable having a tensile strength of 100 N or more.
7. According to clause 1,

   The metal-coated carbon fiber bundle is a heating cable containing 100 to 12,000 monofilament strands.
8. According to clause 1,

   The metal-coated carbon fiber bundle is a heating cable in which carbon fibers are coated with a first metal and a second metal.
9. According to clause 8,

   A heating cable wherein the first metal is nickel or copper, and the second metal is nickel.
10. According to clause 1,

    The first heat-resistant resin layer is made of polyamide (PA), polyethylene (PE), polypropylene (PP), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyvinyl chloride (PVC), and polyvinyl alcohol ( PVA), polystyrene (PS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), acrylonitrile-styrene copolymer resin (SAN), acrylonitrile-styrene -Thermoplastic resins such as acrylate copolymer resin (ASA), polyphenylene ether (PPE), polyphenylene sulfide (PPS), and polyetheretherketone (PEEK); and rubber resins such as natural rubber, ethylene-propylene-diene monomer (EPDM), styrene butadiene, ethylene propylene, chloroprene, hypalon, silicone, and ethylene vinyl acetate. A heating cable comprising any one or two or more selected from the group consisting of:
11. According to clause 1,

    The second heat-resistant resin layer is made of polyamide (PA), polyethylene (PE), polypropylene (PP), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyvinyl chloride (PVC), and polyvinyl alcohol ( PVA), polystyrene (PS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), acrylonitrile-styrene copolymer resin (SAN), acrylonitrile-styrene -Thermoplastic resins such as acrylate copolymer resin (ASA), polyphenylene ether (PPE), polyphenylene sulfide (PPS), and polyetheretherketone (PEEK); and rubber resins such as natural rubber, ethylene-propylene-diene monomer (EPDM), styrene butadiene, ethylene propylene, chloroprene, hypalon, silicone, and ethylene vinyl acetate. A heating cable comprising any one or two or more selected from the group consisting of:
12. According to clause 1,

    A heating cable wherein the metal-coated carbon fiber bundle further includes glass fibers surrounding the metal-coated carbon fiber bundle at a predetermined angle along the outer peripheral surface of the metal-coated carbon fiber bundle.
13. According to clause 12,

    The angle is 30 to 60° based on the longitudinal axis of the metal-coated carbon fiber bundle.
14. According to clause 12,

    The heating cable satisfies the following relational expression 1.

    [Relational Expression 1]

    │D ₀ -D ₉₀ │/D ₀ × 100 ≤ 10

    (In the above relational equation 1, D ₀ and D ₉₀ are the cross-sectional diameters of the heating cable, respectively, D ₀ is the cross-sectional diameter in one direction (μm), and D ₉₀ is the cross-sectional diameter in the vertical direction in one direction (μm).)

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