KR20220076621A - Method for manufacturing carbon nanotube heating ink and heating ink manufactured by the method - Google Patents

Abstract

The present invention relates to a catalyst structure capable of producing a uniform carbon nanotube, a method for manufacturing a carbon nanotube using the same, and a method for producing a carbon nanotube heat generating ink using the same, a heat generating ink prepared according to the method, and a planar heating element including the same will be.

Description

Method for manufacturing carbon nanotube heating ink and heating ink manufactured by the method

The present invention relates to a method for producing a carbon nanotube heating ink and to the heating ink produced thereby.

Carbon nanotube (CNT) is used in many fields because of its excellent chemical stability, excellent mechanical properties, and high thermal conductivity. The carbon nanotube is a single-walled carbon nanotube having a structure in which one layer of graphite structure is rolled up and connected to the ends depending on the synthesis conditions; It is composed of multi-walled carbon nanotubes.

Methods for synthesizing such carbon nanotubes include an electric discharge method, a laser ablation method, a high-pressure vaporization method, a thermochemical vaporization method, and the like.

On the other hand, the carbon nanotubes manufactured by the general method as described above do not have a uniform diameter and have a wide diameter distribution. 1 (a) and (b) are graphs showing the diameter distribution of carbon nanotubes prepared by a conventional conventional carbon nanotube manufacturing method. Referring to FIG. 1( a ), it can be seen that the diameter of the carbon nanotubes is distributed in the range of 1 to 4 nm. In addition, referring to FIG. 1(b), it can be seen that the diameter of the carbon nanotubes is widely distributed in the range of 1.5 nm to 7 nm.

As described above, when carbon nanotubes are manufactured by a conventional method, the carbon nanotubes do not have uniform physical properties because they do not have a uniform diameter. On the other hand, when a dispersion solution is prepared using carbon nanotubes having non-uniform physical properties, there is a problem that the physical properties of the product are also non-uniform. Many attempts have been made on conductive coating solutions using conventional solutions containing carbon nanotubes. For example, there is Republic of Korea Patent No. 10-1155071 "Conductive coating liquid composition and manufacturing method thereof".

However, carbon nanotubes have various stability to specific solvents, so they can be selectively used, and their application as a coating solution is limited. In addition, as time elapses, there may be a problem in that its intrinsic properties deteriorate, and agglomeration may occur due to a strong van der Waals force. This can cause the strands to overlap each other, greatly affecting the movement of current.

Republic of Korea Patent No. 10-1155071 Republic of Korea Patent Registration No. 10-0574030 Republic of Korea Patent Publication No. 10-2014-0028449 Republic of Korea Patent No. 10-1151281

The present invention is to solve the above-mentioned problems, a catalyst structure capable of producing a uniform carbon nanotube and a carbon nanotube using the same, and a method for producing a carbon nanotube heating ink using the same, and the heat produced according to the same We want to provide ink.

In order to achieve the above object, there is provided a method for producing a carbon nanotube heating ink. In one example, the method for producing a carbon nanotube heating ink according to the present invention comprises the steps of introducing uniform catalyst particles between layers of a transition metal chalcogenide (TMDC) to form a catalyst structure (S10); preparing carbon nanotubes having an average particle diameter of 4 to 6 nm by reacting the catalyst structure with a carbon source by chemical vapor deposition (S20); and mixing carbon nanotubes, a binder, and a dispersion solvent to prepare an exothermic ink composition (S30). In this case, the carbon nanotubes have a particle size distribution in the range of 4 nm to 6 nm.

The transition metal chalcogen compound is molybdenum disulfide (MoS ₂ ), molybdenum diselenide (MoSe ₂ ), molybdenum telluride (MoTe ₂ ), tungsten disulfide (WS ₂ ) and tungsten diselenide (WSe ₂ ) The group consisting of It may be one or more selected from. In addition, the catalyst particles may be at least one selected from the group consisting of iron (Fe), nickel (Ni), platinum (Pt), tungsten (W), and cobalt (Co).

In one example, the step of forming the catalyst structure (S10), the process of inserting an alkali metal between the layers of the transition metal chalcogen compound using an alkali metal ion-containing compound (S11); A process of replacing the alkali metal intercalated between the layers of the transition metal chalcogenide compound with catalyst particles by heat treatment after mixing the transition metal chalcogen compound and the catalyst particle chloride in which the alkali metal is intercalated in an organic solvent (S12); A catalyst precursor solution is prepared by dispersing the transition metal chalcogen compound introduced with the catalyst particles in an organic solvent, and the catalyst precursor solution is loaded on a SiO ₂ /Si substrate placed in a chemical vapor deposition chamber, and then heat treated to obtain a catalyst structure It includes a manufacturing process (S13).

In a specific example, in the process (S13) of preparing a catalyst structure by heat treatment, a catalyst precursor solution is loaded on a SiO ₂ /Si substrate placed in a chemical vapor deposition chamber, and one selected from the group consisting of argon, methane and hydrogen The process of heat treatment in a gas atmosphere above, but in an argon gas atmosphere in a temperature range of 700 to 1100 ℃; The process of heat treatment in a temperature range of 800 to 1200 ℃ in hydrogen and methane gas atmosphere; and cooling to room temperature in an argon and hydrogen gas atmosphere.

In addition, the manufacturing of the carbon nanotubes (S20), the process of growing carbon nanotubes on the surface of the catalyst structure by chemical vapor deposition (S21) and acid treatment of the catalyst structure in which the carbon nanotubes are grown, the catalyst structure It may include the process of removing

Furthermore, preparing the exothermic ink composition (S30) may include mixing 1 to 10 parts by weight of carbon nanotubes in the range of 4 to 6 nm, 2 to 10 parts by weight of a binder, and 85 to 95 parts by weight of a dispersion solvent. have.

In this case, the binder may include at least one selected from the group consisting of polyurethane, acrylic, polyester, melamine, vinyl chloride, polyimide, polyolefin, phenol, PVA, epoxy, silicone, and a fluororesin, and dispersed therein. The solvent may be at least one selected from the group consisting of terpineol, sodium dodecylsulfonate, sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, polyvinylbutyral, polyvinyl alcohol, Triton x-100, and polyacrylic acid. .

In addition, the present invention provides a heating ink manufactured according to the method for producing the carbon nanotube heating ink described above. In a specific example, the heating ink may have a viscosity in the range of 1,000 to 50,000 cP at an average temperature of 25 °C.

According to the method for producing a carbon nanotube heating ink of the present invention, a conductive solution capable of maximizing physicochemical properties can be prepared by using carbon nanotubes having a uniform particle size.

1 is a graph showing a conventional conventional carbon nanotube manufacturing method and a diameter distribution diagram of the carbon nanotube manufactured according to the present invention.
2 is a flowchart illustrating a method for producing a carbon nanotube heating ink of the present invention.
3 is a view schematically illustrating a process of manufacturing a catalyst structure according to the present invention.
4 is a schematic diagram showing the structure of MoS ₂ in one example of the present invention.
5 is a schematic diagram showing a structure of LixMoS ₂ in which lithium ions are intercalated between MoS ₂ layers in an example of the present invention.
6 is a schematic diagram showing a state of Co-MoS ₂ in which lithium ions are substituted with Co particles in an example of the present invention, and Co particles are inserted.
7 is a diagram schematically illustrating a process of preparing a catalyst structure by heat-treating a transition metal chalcogen compound into which catalyst particles are introduced in a CVD chamber in one example of the present invention.
8 is a graph showing temperature and gas atmosphere according to time in a process of heat-treating a catalyst precursor solution in an example of the present invention.
9 is a view schematically showing a state in which sulfur (S) component is volatilized and removed from MoS ₂ in one example of the present invention.
10 is a view showing a Mo-Co alloy catalyst prepared in one example of the present invention.
11 is a photograph taken with a transmission electron microscope of MoS ₂ synthesized in Synthesis Example.
12 is a picture taken with a transmission electron microscope of LixMoS ₂ in which Li ions are intercalated between MoS ₂ layers.
13 is a picture taken with a transmission electron microscope of the synthesized Co-MoS ₂ .
14 is a photograph taken with a scanning electron microscope of the manufactured multi-wall carbon nanotube.
15 is a photograph of the flowability and viscosity of the exothermic ink prepared in Example 1.
16 is an IR image image that is heated when a voltage is applied to the planar heating element manufactured in Example 2.
17 is a graph showing the temperature rise according to time for each voltage application of the planar heating element manufactured in Example 2 and Comparative Example 2.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description.

However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing the present invention, if it is determined that a detailed description of a related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present invention, terms such as "comprises" or "have" are intended to designate that the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist, but one or more other features It should be understood that this does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

The present invention provides a method for producing a carbon nanotube heating ink, and the heating ink prepared accordingly.

In the case of manufacturing the conventional carbon nanotubes, there is a problem in that the carbon nanotubes do not have uniform physical properties because they do not have a uniform diameter. In particular, when a dispersion solution or exothermic ink is prepared with carbon nanotubes that do not have uniform physical properties, aggregation occurs due to the strong van der Waals force of the carbon nanotubes, and thus the strands of the carbon nanotubes overlap each other. There was a problem affecting the current transfer.

Accordingly, the present invention provides a method by which carbon nanotubes can be synthesized uniformly from the catalyst preparation process, and by using the method, carbon nanotube exothermic ink that minimizes aggregation of carbon nanotube strands as well as maximizes physicochemical properties. A manufacturing method is provided.

Hereinafter, the present invention will be described in more detail.

Manufacturing method of carbon nanotube heating ink

2 is a flowchart illustrating a method for producing a carbon nanotube heating ink of the present invention.

Referring to Figure 2, the present invention in one embodiment,

Forming a catalyst structure by introducing catalyst particles between the layers of a transition metal chalcogenide (TMDC, transition metal dichalcogenide) (S10);

preparing carbon nanotubes having an average particle diameter of 4 to 6 nm by reacting the catalyst structure with a carbon source by physical vapor deposition (S20); and

It provides a method for producing a carbon nanotube heating ink comprising the step (S30) of preparing a heating ink composition by mixing carbon nanotubes, a binder, and a dispersion solvent.

The method for producing a carbon nanotube exothermic ink according to the present invention forms a catalyst structure having a uniform diameter between multilayer transition metal chalcogenide (TMDC) layers stacked at uniform intervals, and using the catalyst structure as a precursor A carbon nanotube having a uniform diameter is manufactured by a chemical vapor deposition method. In particular, since the carbon nanotube has uniform properties, there is an advantage in that the physical properties of the carbon nanotube heating ink including the same are also uniform.

In the present invention, "transition metal chalcogenide (TMDC, transition metal dichalcogenide)" is a two-dimensional layered material similar to graphene, and refers to a compound made by combining one or more chalcogen anions and other cations. More specifically, the transition metal chalcogen compound has a structural formula of MX ₂ (M is a transition metal, X is a chalcogen element). In particular, in the present invention, it is possible to form a catalyst material between the transition metal chalcogen compound layer. This is, by using the multi-layered TMDC in which the transition metal chalcogenide compound is naturally stacked with uniform spacing as a framework, the catalyst material can be grown into nanoparticles of uniform diameter. Accordingly, in the present invention, a catalyst structure having a uniform diameter can be manufactured, and carbon nanotubes having a uniform diameter can be manufactured by using the catalyst structure as a precursor. Furthermore, carbon nanotubes having a uniform diameter can exhibit excellent heating effect and the like by being made of a heating ink.

Forming a catalyst structure (S10)

3 is a view schematically illustrating a process of manufacturing a catalyst structure according to the present invention.

3, in the present invention, in one embodiment, the step of forming the catalyst structure (S10) is a process of inserting an alkali metal between the layers of a transition metal chalcogen compound using an alkali metal ion-containing compound (S11) ;

A process of replacing the alkali metal intercalated between the layers of the transition metal chalcogenide compound with catalyst particles by heat treatment after mixing the transition metal chalcogen compound and the catalyst particle chloride in which the alkali metal is intercalated in an organic solvent (S12);

A catalyst precursor solution is prepared by dispersing the transition metal chalcogen compound introduced with the catalyst particles in an organic solvent, and the catalyst precursor solution is loaded on a SiO ₂ /Si substrate placed in a chemical vapor deposition chamber, and then heat treated to obtain a catalyst structure It includes a manufacturing process (S13).

In one example, the transition metal chalcogenide compound (TMDC) is molybdenum (Mo), tungsten (W), tin (Sn), cadmium (Cd), vanadium (V), niobium (Nb), nickel (Ni) , a transition metal atom of any one of iron (Fe), copper (Cu), and zinc (Zn) and at least one chalcogen valence of selenium (Se), sulfur (S), phosphorus (P), and tellurium (Te) It may be a bound compound. The transition metal chalcogenide compound is molybdenum disulfide (MoS ₂ ), molybdenum diselenide (MoSe ₂ ), molybdenum telluride (MoTe ₂ ), tungsten disulfide (WS ₂ ) and tungsten diselenide (WSe ₂ ) The group consisting of It may be one or more selected from. Specifically, the transition metal chalcogenide compound may be one or more selected from the group consisting of molybdenum disulfide (MoS ₂ ), tungsten disulfide (WS ₂ ), and tungsten diselenide (WSe ₂ ). For example, the transition metal chalcogenide compound may be molybdenum disulfide (MoS ₂ ).

4 is a schematic diagram showing the structure of MoS ₂ in one example of the present invention. Referring to Figure 4, the transition metal chalcogenide compound MoS ₂ has a 2H phase. MoS ₂ Silver has 2-3 layers and may have a length of about 100 nm in the lateral direction. Furthermore, the interlayer spacing may be maintained at about 1 nm by the van der Waals force.

In addition, the catalyst particles introduced between the layers of the transition metal chalcogenide compound (TMDC) are selected from the group consisting of iron (Fe), nickel (Ni), platinum (Pt), tungsten (W) and cobalt (Co). There may be more than one. For example, the catalyst particles may be cobalt (Co).

The process of inserting an alkali metal between the layers of a transition metal chalcogen compound using an alkali metal ion-containing compound (S11)

First, for intercalation of an alkali metal into an interlayer of a transition metal chalcogen compound, a conventionally known method, for example, an ion exchange method, an acid-base reaction, hydrogen bonding, a redox reaction, an electrochemical reaction (for example, , electrochemical lithiation: using a Li foil as anode, and a MoS2-containing cathode), etc., by grinding the reaction mixture using mortar and pestle, direct intercalation methods, etc. to obtain solid-solid and solid-liquid A method of mechanically intercalating through a (solid-liquid) interface may be used, but in a specific example, an alkali metal compound (eg, lithium, sodium, potassium, etc.), specifically a compound containing an alkali metal ion, may be used. An interlayer insertion method can be applied.

More specifically, a compound containing lithium ions may be used for intercalation. Examples of such lithium ion-containing compounds include n-butyllithium, KOH, NaOH, NaCl, KCl. or a combination thereof. The lithium intercalation described above may be performed in an organic solvent, specifically, an organic solvent selected from hexane, THF, benzene, toluene, and combinations thereof. In this case, the molar ratio of the lithium ion-containing compound: MoS ₂ in the bulk phase may be in the range of, for example, about 1 to 10: 1, specifically about 2 to 7: 1, more specifically about 3 to 5: 1, Also, the concentration of the organic solvent introduced (or dissolved) lithium ion-containing compound may range, for example, from about 0.5 to 3 M, specifically from about 0.7 to 2 M, more specifically from about 1 to 1.5 M.

In a specific example, the above-described intercalation reaction may be performed under an inert atmosphere, for example, nitrogen, argon, neon, or the like, and the intercalation reaction is, for example, about 20 to 60 ° C., specifically about 25 to about 25 ° C. 40° C., more specifically about 25° C., for example, for at least about 24 hours (specifically at least about 40 hours, more specifically at least about 48 hours). These reaction conditions are exemplary, and the present invention is not necessarily limited thereto.

As described above, by the intercalation process, the alkali metal is inserted while penetrating between the layers of the layered MoS2 compound, for example, LixMoS ₂ (when the alkali metal is lithium) may be formed.

5 is a schematic diagram showing a structure of LixMoS ₂ in which lithium ions are intercalated between MoS ₂ layers in an example of the present invention. Referring to FIG. 5 , the phase of MoS ₂ may be changed to 1T' due to the change in the electron velocity.

The process of replacing the alkali metal inserted between the layers of the transition metal chalcogen compound with catalyst particles (S12)

In one example, the present invention mixes the transition metal chalcogen compound and the catalyst particle chloride in which the alkali metal is intercalated in an organic solvent and then heat-treats the alkali metal intercalated between the layers of the transition metal chalcogen compound as catalyst particles It involves the process of substituting.

The catalyst particle chloride may be one or more catalyst components selected from (Fe), nickel (Ni), platinum (Pt), tungsten (W) and cobalt (Co), specifically, (Fe), nickel (Ni) , platinum (Pt), tungsten (W) and cobalt (Co) may be one or more salts, oxides or compounds. More specifically, the catalyst particle chloride is Fe(NO ₃ ) ₂ ·6H ₂ O, Fe(NO ₃ ) ₂ ·9H ₂ O, Fe(NO ₃ ) ₃ , Fe(OAc) ₂ , Ni(NO ₃ ) ₂ · 6H ₂ O, Co(NO ₃ ) ₂ 6H ₂ O, Co ₂ (CO) ₈ , [Co ₂ (CO)6(t-BuC=CH)] and Co(OAc) ₂ may be selected from the group consisting of have. For example, the catalyst particle chloride may be Co(NO ₃ ) ₂ .6H ₂ O.

In a specific example, the process of replacing the alkali metal inserted between the layers of the transition metal chalcogen compound with catalyst particles is the lithium ion intercalated MoS ₂ NMP (N-Methyl-2-Pyrrolidone), cobalt chloride 60 to The reaction can be carried out at a temperature of 120 °C for 48 hours.

6 is a schematic diagram showing a state of Co-MoS ₂ in which lithium ions are substituted with Co particles in an example of the present invention, and Co particles are inserted.

Referring to Figure 6, MoS ₂ phase returns to 2H. At this time, the diameter of the Co particles may be constant to about 3 to 5 nm due to the limited interlayer spacing of MoS ₂ due to the van der Waals force.

Process of manufacturing a catalyst structure by heat treatment (S13)

In one example, the present invention prepares a catalyst precursor solution by dispersing the transition metal chalcogen compound into which the catalyst particles are introduced in an organic solvent, and the catalyst precursor solution is placed in a chemical vapor deposition chamber on a SiO ₂ /Si substrate It includes a process (S13) of preparing a catalyst structure by heat-treating after loading.

7 is a diagram schematically illustrating a process of preparing a catalyst structure by heat-treating a transition metal chalcogen compound into which catalyst particles are introduced in a CVD chamber in one example of the present invention.

First, a catalyst precursor solution is prepared by dispersing the transition metal chalcogen compound into which the catalyst particles are introduced in an organic solvent. For example, Co-MoS ₂ A catalyst precursor solution may be prepared by dispersing in ethanol.

In addition, the catalyst precursor solution may be loaded on a SiO ₂ /Si substrate placed in a chemical vapor deposition chamber by a drop-dry method. Specifically, the catalyst precursor solution is loaded onto a SiO ₂ /Si substrate placed in a chemical vapor deposition chamber, and heat treatment is performed in one or more gas atmospheres selected from the group consisting of argon, methane and hydrogen.

8 is a graph showing temperature and gas atmosphere according to time in a process of heat-treating a catalyst precursor solution in an example of the present invention.

Referring to FIG. 8 , the heat treatment of the catalyst precursor solution includes heat treatment at a temperature ranging from 700 to 1100° C. in an argon gas atmosphere; The process of heat treatment in a temperature range of 800 to 1200 ℃ in hydrogen and methane gas atmosphere; and cooling to room temperature in an argon and hydrogen gas atmosphere.

In a specific example, the catalyst precursor solution may be loaded on a SiO ₂ /Si substrate by a drop-dry method. A vacuum of about 100 mTorr can be created by evacuating the CVD chamber for about 10 minutes. For example, the temperature is raised to 900° C. for 1 hour under an Ar flow of 1000 sccm. 900 °C was maintained for 2 hours under an Ar flow of 1000 sccm, and the temperature was raised to 950 °C for 30 minutes under an Ar flow of 1000 sccm. In this calcination process, the sulfur (S) component is volatilized and removed. And, 50 sccm of H ₂ , 300 sccm of CH ₄ is maintained at 950° C. for 30 minutes under a flow. Next, 1000 sccm of Ar, 50 sccm of H ₂ It is cooled to room temperature under the flow. Then, a Mo-Co alloy catalyst can be prepared.

9 is a view schematically showing a state in which sulfur (S) component is volatilized and removed from MoS ₂ in an example of the present invention, and FIG. 10 is a Mo-Co alloy prepared in one example of the present invention It is a drawing showing a catalyst.

9 to 10 , as described above, the sulfur component is volatilized and removed during the calcination process, and a catalyst structure having a uniform diameter (D) can be prepared. For example, a Mo-Co alloy catalyst can be prepared.

Manufacturing carbon nanotubes (S20)

In one embodiment, the present invention includes a step (S20) of preparing carbon nanotubes having an average particle diameter of 4 to 6 nm by reacting a catalyst structure with a carbon source by a physical vapor deposition method.

In one example, the manufacturing of the carbon nanotubes (S20) includes the process of growing carbon nanotubes on the surface of the catalyst structure by chemical vapor deposition (S21) and acid treatment of the catalyst structure on which the carbon nanotubes are grown. and removing the catalyst structure.

As described above, the catalytic material can be grown into nanoparticles having a uniform diameter by using the multi-layered TMDC in which the transition metal chalcogen compound is naturally stacked at uniform intervals as a framework. Accordingly, in the present invention, a catalyst structure having a uniform diameter can be manufactured, and carbon nanotubes having a uniform diameter can be manufactured by using the catalyst structure as a precursor. For example, the average diameter of the carbon nanotubes may be 4 to 6 nm. On the other hand, hydrocarbons such as methane or acetylene are decomposed at a temperature of 800 °C or higher, and can be continuously synthesized in the catalyst.

In particular, according to the present invention, the carbon nanotubes may have a particle size distribution in the range of 4 nm to 6 nm. That is, according to the present invention, carbon nanotubes having a uniform particle size can be manufactured.

Preparing the exothermic ink composition (S30)

In one embodiment, the present invention includes a step (S30) of preparing a heating ink composition by mixing carbon nanotubes, a binder, and a dispersion solvent.

In a specific example, preparing the exothermic ink composition (S30) includes mixing 1 to 10 parts by weight of carbon nanotubes in the range of 4 to 6 nm, 2 to 10 parts by weight of a binder, and 85 to 95 parts by weight of a dispersion solvent do.

In the exothermic ink composition, the tube of the carbon nano exothermic ink composition may contain 1 to 10 parts by weight, 2 to 8 parts by weight, and 3 to 6 parts by weight, for example, it may include an average of 3 parts by weight. If the amount of the carbon nanotube is less than 1 part by weight, the desired heating efficiency may not be provided because the content of the carbon nanotube is too small. may cause problems with entanglement with each other.

In addition, the binder may include 2 to 10 parts by weight, 3 to 9 parts by weight, 4 to 8 parts by weight, and 5 to 7 parts by weight, for example, may include an average of 5 parts by weight. If the content of the binder is less than 2 parts by weight, the carbon nanotubes may not be easily dispersed in the dispersion solvent, and if it exceeds 10 parts by weight, the exothermic efficiency may be poor.

Further, the dispersion solvent may contain 85 to 95 parts by weight, specifically 87 to 94 parts by weight, 89 to 93 parts by weight, or 91 to 92 parts by weight, for example, including an average of 92 parts by weight can do.

In one example, the binder may include at least one selected from the group consisting of polyurethane, acrylic, polyester, melamine, vinyl chloride, polyimide, polyolefin, phenol, PVA, epoxy, silicone, and fluororesin. can In addition, the dispersion solvent includes at least one selected from the group consisting of sodium dodecylsulfonate, sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, polyvinylbutyral, polyvinyl alcohol, Triton x-100, and polyacrylic acid. can do.

For example, the binder may be ethyl cellulose, and the dispersion solvent may be terpineol.

Meanwhile, the exothermic ink composition may further include an additional additive, and the additive may be at least one selected from the group consisting of an antifoaming agent, a surfactant, an anti-freezing agent, an aqueous thickener, a preservative, a plasticizer, and a pH buffer.

heat ink

The present invention provides a heating ink prepared according to the method for producing the carbon nanotube heating ink described above. The exothermic ink according to the present invention can minimize the aggregation of carbon nanotube strands, including carbon nanotubes having a uniform particle size, as well as maximize physicochemical properties. On the other hand, the heating ink prepared according to the present invention may have a viscosity in the range of 1,000 to 50,000 cP at an average temperature of 25 ℃.

Hereinafter, the present invention will be described in more detail by way of Examples and Experimental Examples.

However, the following Examples and Experimental Examples are merely illustrative of the present invention, and the content of the present invention is not limited to the following Examples and Experimental Examples.

Synthesis example

One. MoS ₂ synthesis

Molybdenum hexacarbonyl (Mo(CO) ₆ ) and 1-dodecanethiol (CH ₃ (CH ₂ ) ₁₀ CH ₂ SH)) with a small amount of trioctylphosphine added with oleic acid (oleic acid) acid), and reacted at 300 °C for 6 hours to synthesize MoS ₂ .

11 is a photograph taken with a transmission electron microscope of MoS ₂ synthesized in Synthesis Example. In FIG. 11 , MoS ₂ shown in the turquoise color was observed in the white dotted line.

2. MoS ₂ between floors Li ion insertion

In order to synthesize Co nanoparticles between the synthesized MoS ₂ layers, Li ions are first inserted. More specifically, MoS ₂ synthesized in Synthesis Example in a 1.2 M n-butyllithium solution After being impregnated with Ar to N ₂ and reacted in an atmosphere for 48 hours, Li ions were inserted between the MoS ₂ layers to prepare LixMoS ₂ .

12 is a picture taken with a transmission electron microscope of LixMoS ₂ in which Li ions are intercalated between MoS ₂ layers. LixMoS ₂ is shown in turquoise in the white dotted circle in FIG. 12 .

3. MoS ₂ Interlayer Co Nanoparticle Synthesis

In order to replace Li ions with Co nanoparticles, MoS ₂ into which Li ions are inserted was reacted with NMP (N-Methyl-2-Pyrrolidone) and Co precursors at 80 ° C. for 48 hours to prepare Co-MoS ₂ did

13 is a picture taken with a transmission electron microscope of the synthesized Co-MoS ₂ . In FIG. 13 , the color indicated in blue in the colored dotted circle is Co-MoS ₂ .

catalyst production example

One. Mo Preparation of -Co alloy catalyst

Co-MoS ₂ synthesized in Synthesis Example was dispersed in ethanol to prepare a CNT catalyst precursor solution.

On the SiO ₂ /Si substrate placed in the CVD chamber, the CNT catalyst precursor solution is loaded by a drop-dry method. Then, air is removed from the CVD chamber for about 10 minutes to create a vacuum degree of about 100 mTorr.

Then, the temperature of the CVD chamber in a vacuum state was increased to 900° C. for 1 hour under an Ar flow of 1000 sccm. It was maintained at 900 °C for 2 hours under an Ar flow of 1000 sccm, and the temperature was raised to 950 °C for 30 minutes under an Ar flow of 1000 sccm.

In this calcination process, the sulfur (S) component is volatilized and removed. And, after maintaining 950 °C for 30 minutes under a flow of 50 sccm H ₂ and 300 sccm CH ₄ , it was cooled to room temperature under a flow of 1000 sccm Ar and 50 sccm H ₂ .

Accordingly, a Mo-Co alloy catalyst having a uniform average diameter was prepared.

2. Mo -Manufacturing of carbon nanotubes using Co alloy catalyst

Carbon nanotubes were manufactured by performing a CVD process in a CVD chamber containing the Mo-Co alloy catalyst. Specifically, the CVD process was performed while flowing Ar/H ₂ /CH ₄ gas into the CVD chamber.

Multi-walled carbon nanotubes (MWCNTs) with uniform diameters were manufactured while carbon components were deposited and grown on the surface of the Mo-Co alloy catalyst having a uniform diameter. On the other hand, the Mo-Co alloy catalyst contained in the multi-wall carbon nanotubes (MWCNT) was removed by acid treatment.

14 is a photograph taken with a scanning electron microscope of the manufactured multi-wall carbon nanotube.

Referring to FIG. 14 , it can be seen that the diameter of the multi-walled carbon nanotubes (MWCNT) is almost uniform, ranging from 4 to 6 nm.

Example 1. Manufacture of heating ink

3.0 g of the multi-walled carbon nanotube bundle prepared in Preparation Example, 5.0 g of ethyl cellulose (ETHOCEL, standard 45, Dow Chemical Corp, USA) was added to 92.0 g of a terpineol dispersion solvent, mixed and 60 for 180 minutes After stirring at a temperature of ℃, the exothermic ink was prepared by milling at room temperature for 60 minutes with a 3-Roll Mill equipment.

15 is a photograph of the flowability and viscosity of the exothermic ink prepared in Example 1. Referring to FIG. 15 , the flowability of the exothermic ink prepared in Example 1 was excellent, and the viscosity was about 18,000 cP.

comparative example 1. Manufacture of heating ink

A heating ink was prepared in the same manner as in Example 1, except that commercial multi-walled carbon nanotubes (Hanwha Nanotech, product name: CM-95) were used. On the other hand, commercial multi-walled carbon nanotubes were not uniform in diameter, and the average diameter was 12.5 nm. In addition, the average length was 15.0 µm.

Example 2. Manufacture of planar heating element

A planar heating element was prepared using the heating ink prepared in Example 1. Specifically, the carbon nanotube heating ink prepared in Example 1 is applied on a polyimide film using screen printing equipment, and then a conductive paste, silver (Ag) paste, is pattern-printed to form an electrode, and the temperature is 300°C. Dry heat treatment was carried out in a carbon nanotube heating planar body by attaching an electric wire to the silver paste electrode part for the purpose of applying a voltage.

comparative example 2. Manufacture of planar heating element

It was carried out in the same manner as in Example 2, except that the planar heating element paste of Comparative Example 1 was used.

Experimental example 1. Thermal Characteristics and Thermal Image Analysis

The surface of the planar heating element prepared in Example 2 and Comparative Example 2 was observed with an IR imaging camera, and the results are shown in FIG. 16 . As shown in FIG. 16, it can be seen that the surface of the carbon nanotube planar heating element according to the present invention is formed more evenly than that of the conventional carbon nanotube planar heating element. Specifically, after supplying a current of 500 mA to the planar heating element of Example 2 and Comparative Example 2 as a DC power supply device, the temperature was measured using a thermal imaging camera in a state where the temperature no longer changes.

Experimental example 2. Exothermic analysis

A power supply (DC 2.5 V ~ 10 V) was connected to the film coated with the carbon heating paste prepared in Example 2 and Comparative Example 2 to measure the heating performance, and the results are graphically represented in FIG. 17 . Voltage was delivered for a total of 60 minutes, and the temperature change value was continuously measured.

And, the results are shown in Table 1 below.

applied voltage
(60 min) Sat. Temperature Max. Temperature Comparative Example 2
(℃) Example 2
(℃) Comparative Example 2
(℃) Example 2
(℃) △
(Example 2
-Comparative Example 2) 2.5 V 25 to 27 25 to 27 28.4 28.3 -0.1 5 V 32 to 34 42 to 45 37.1 49.8 12.7 7.5 V 53 to 55 70 to 72 58.7 77.3 18.6 10 V 85 to 87 98 to 100 91.1 103.0 11.9

Referring to Table 1 and FIG. 17, it can be seen that the heat generation performance of the Example compared to the Comparative Example is excellent.

Claims (11)

Forming a catalyst structure by introducing catalyst particles between the layers of a transition metal chalcogenide (TMDC, transition metal dichalcogenide) (S10);
preparing carbon nanotubes having an average particle diameter of 4 to 6 nm by reacting the catalyst structure with a carbon source by physical vapor deposition (S20); and
A method for producing a carbon nanotube heating ink comprising the step (S30) of preparing a heating ink composition by mixing carbon nanotubes, a binder, and a dispersion solvent.
The method of claim 1,
The carbon nanotube, a method for producing a carbon nanotube heating ink, characterized in that having a particle size distribution in the range of 4nm to 6nm.
The method of claim 1,
Transition metal chalcogen compounds are from the group consisting of molybdenum disulfide (MoS ₂ ), molybdenum diselenide (MoSe ₂ ), molybdenum telluride (MoTe ₂ ), tungsten disulfide (WS ₂ ) and tungsten diselenide (WSe ₂ ) A method for producing one or more selected carbon nanotube heating inks.
The method of claim 1,
The catalyst particles are at least one selected from the group consisting of iron (Fe), nickel (Ni), platinum (Pt), tungsten (W) and cobalt (Co).
The method of claim 1,
Forming the catalyst structure (S10),
The process of inserting an alkali metal between the layers of a transition metal chalcogen compound using an alkali metal ion-containing compound (S11);
A process of replacing the alkali metal intercalated between the layers of the transition metal chalcogenide compound with catalyst particles by heat treatment after mixing the transition metal chalcogen compound and the catalyst particle chloride in which the alkali metal is intercalated in an organic solvent (S12);
A catalyst precursor solution is prepared by dispersing the transition metal chalcogen compound introduced with the catalyst particles in an organic solvent, and the catalyst precursor solution is loaded on a SiO ₂ /Si substrate placed in a chemical vapor deposition chamber, and then heat treated to obtain a catalyst structure A method of manufacturing a carbon nanotube heating ink comprising a manufacturing process (S13).
6. The method of claim 5,
The process of preparing a catalyst structure by heat treatment (S13) is,
A catalyst precursor solution is loaded on a SiO ₂ /Si substrate placed in a chemical vapor deposition chamber, and heat-treated in one or more gas atmospheres selected from the group consisting of argon, methane and hydrogen,
The process of heat treatment at a temperature range of 700 to 1100 °C in an argon gas atmosphere;
The process of heat treatment in a temperature range of 800 to 1200 ℃ in hydrogen and methane gas atmosphere; and
A method for producing a carbon nanotube exothermic ink comprising the process of cooling to room temperature in an argon and hydrogen gas atmosphere.
The method of claim 1,
The step of manufacturing the carbon nanotube (S20),
The process of growing carbon nanotubes on the surface of the catalyst structure by chemical vapor deposition (S21) and
A method for producing a carbon nanotube exothermic ink comprising the step of removing the catalyst structure by acid-treating the catalyst structure in which the carbon nanotubes are grown.
The method of claim 1,
The step of preparing the exothermic ink composition (S30),
1 to 10 parts by weight of carbon nanotubes in the range of 4 to 6 nm, 2 to 10 parts by weight of a binder, and 85 to 95 parts by weight of a dispersion solvent A method for producing a carbon nanotube exothermic ink.
9. The method of claim 8,
The binder, polyurethane, acryl, polyester, melamine, vinyl chloride, polyimide, polyolefin, phenol, PVA, epoxy, silicone, and carbon nanotube heat generating that includes at least one selected from the group comprising a fluororesin A method for producing ink.
9. The method of claim 8,
The dispersion solvent is at least one carbon selected from the group consisting of terpineol, sodium dodecylsulfonate, sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, polyvinylbutyral, polyvinyl alcohol, triton x-100 and polyacrylic acid. Method for manufacturing nanotube heating ink.
[Claim 11] A heating ink produced according to the method for producing a carbon nanotube heating ink according to any one of claims 1 to 10, and having a viscosity in the range of 1,000 to 50,000 cP at an average temperature of 25 °C.

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