KR102222803B1 - Humidity sensing film for humidity sensor including carbon doped with nano metal and method for manufacturing the same - Google Patents

Abstract

The present invention provides a moisture sensor for a humidity sensor comprising 5 to 20% by weight of carbon doped with nanometals, 10 to 40% by weight of a hydrophilic organic polymer, 0.01 to 10% by weight of a crosslinking agent, and 30 to 50% by weight of a conductive polymer.
The moisture sensor for a humidity sensor of the present invention includes carbon doped with nanometals, so that the physical adsorption and chemical adsorption of hydroxyl groups on the surface is smooth, so that sensitivity, linearity, and reaction speed can be improved, and the electrical resistance of the moisture sensitive film can be lowered. There is an advantage applicable to electronic circuits and the like.

Description

Moisture sensor for humidity sensor containing carbon doped with nano metal and its manufacturing method {HUMIDITY SENSING FILM FOR HUMIDITY SENSOR INCLUDING CARBON DOPED WITH NANO METAL AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a moisture-sensitive film for a humidity sensor containing carbon doped with a nano-metal and a method of manufacturing the same.

In general, a sensor refers to an element with a function of detecting or measuring physical quantities such as temperature, pressure, sound, and light, and transmitting them as a signal, or a measuring instrument using such elements, and in particular, a sensor that detects or detects changes in humidity in the air. It is called a humidity sensor.

In such a humidity sensor, a moisture-sensitive membrane that responds to humidity is a particularly key component. The ceramic humidity sensor, which is mainly made of ceramic containing metal oxides, detects changes in humidity in the atmosphere by measuring the degree of change in resistance value of ceramics as moisture is adsorbed or desorbed on the ceramic surface according to changes in ambient humidity.

The humidity sensor using such a metal oxide material has many problems. Specifically, the manufacturing process is performed in a vacuum deposition process or a high-temperature sintering process, and there is no flexibility of the sensor substrate, and in general, a humidity sensor requires periodic reproducibility. In the case of a humidity sensor using a metal oxide, it is exposed to the external environment for a long time. When this occurs, chemically stable hydroxides are formed on the sensor surface, and there is a problem that it does not return to its original state. In addition, in order to remove moisture adsorbed in the pores, a desorption process must be regularly performed, and when dust or the like is adsorbed in the pores, it is difficult to remove it, making it difficult to expect reproducibility as a sensor. Therefore, in recent years, the development of a humidity sensor using a hydrophilic polymeric polymer material having excellent affinity for moisture has been spurred. Polymers are inexpensive, and the manufacturing process can be easily processed at low temperatures. In particular, PVA (polyvinyl alcohol) is a typical general-purpose hydrophilic polymer that is sensitive to moisture because it is inexpensive and has -OH groups between carbon atoms in terms of chemical structure. PVA's high affinity for water molecules causes changes in the electrical properties of the sensor due to the adsorption and desorption of water molecules, but its solubility in water is also high, so when applied to a humidity sensor in the form of a film, it is easily attacked by moisture and is durable. There is a drawback of this lack and showing very high impedance. In addition, even a slightly improved organic polymer material is generally limited in its use due to inherent characteristics such as low strength and durability, low conductivity compared to metal oxide semiconductor materials, and complexity of AC high frequency circuit configuration according to ion conduction properties. These materials have low response speed, high hysteresis, and short lifespan, and these drawbacks are particularly exacerbated when exposed to high temperatures and relative humidity.

To compensate for these shortcomings, there is a method of adding organic, inorganic, and metallic substances of various characteristics to a hydrophilic polymer such as PVA.In particular, the polymerized polymer electrolyte humidity sensor is appropriately grouped with chemical organic/inorganic elements required to improve sensor characteristics. It is excellent in that it is possible to manufacture a polymer electrolyte-type moisture-sensitive material by adding and controlling the mixing, and that it can change the physical properties of the sensor. However, the electrolytic type has a high electrical resistance and uses an ionic conductivity, so the circuit is complicated and reproducibility is insufficient due to the use of a high frequency of 1KHz or more.

Even if prepared as described above, it is difficult to deviate from the range of the ion conductive moisture sensitive material. Therefore, in the present invention, a technology for producing and using an electron conductive moisture sensitive composite material through the task of polymerizing by crosslinking with a hydrophilic polymer by using a carbon powder with a large specific surface area impregnated with a nano metal or a nano metal oxide together with an electrically conductive polymer material. Developed.

On the other hand, the conventional patent document 1 is not a hydrophilic polymer and does not contain a metal salt, which lacks sensitivity and linearity among the moisture-reducing properties, and patent document 2 uses an ammonium salt copolymer, which provides a manufacturing process having a long reaction time of 30 hours. Patent Literature 3 is a crosslinked sensitizing film using a silane group on a vinyl monomer, and Patent Literature 4 is a moisture-sensitive material composed of polyimide as a parent material without any additional elements. The above-described patent documents have a high resistance as a material having an ion-conducting property, and the detection circuit is complicated because an AC power source of 1KHz must be used, and there are various problems in the detection property, so the use thereof is limited.

Unlike this method, it is more effective to use a composite material prepared by mixing a crosslinked polymer and a hydrophilic polymer in which a metal-supported activated carbon powder is added to an electron conductive polymer as a moisture-sensitive material. Such an electron-conducting polymer-based moisture-sensitive material can detect a voltage-divided sensor signal with a 5-bult DC power supply because of its low resistance, has good sensitivity, and has excellent linearity and reproducibility of the detection myth.

Korean Patent Registration No. 10-0539392 Korean Patent Registration No. 10-0548785 Korean Patent Registration No. 10-0529537 Korean Patent Registration No. 10-0753801

An object of the present invention is to provide a moisture-sensitive membrane for a humidity sensor with improved electrical conductivity, moisture detection, and durability while maintaining the humidity sensing properties and processing ease of a hydrophilic polymer.

The object of the invention is not limited to the object mentioned above. The object of the present invention will become more apparent from the following description, and will be realized by the means described in the claims and combinations thereof.

The humidity sensor for a humidity sensor according to an embodiment of the present invention for achieving the above object is nano-metal-doped carbon 5 to 20% by weight, hydrophilic polymer 10 to 40% by weight, crosslinking agent 0.01 to 10% by weight, and It contains 30-50% by weight of a conductive polymer.

Here, in the nanometal-doped carbon, the nanometal exists in a form deposited or supported in a plurality of pores of the carbon, and the nanometal is tin (Sn), zinc (Zn), titanium (Ti), tungsten (W ), indium (In), nickel (Ni), iron (Fe), copper (Cu), cobalt (Co), silver (Ag), vanadium (V), and oxides thereof.

In addition, the hydrophilic polymer may be one selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), and combinations thereof.

In addition, the crosslinking agent may be one selected from a sodium salt of m-benzenedisulfonic acid, a sodium salt of p-styrenesulfonic acid, polyacrylic acid, and combinations thereof.

In addition, the conductive polymer may be one selected from polyaniline, polypyrrole, polythiophene, and combinations thereof.

A method of manufacturing a moisture sensor for a humidity sensor according to another embodiment of the present invention includes the steps of: (a) mixing nanometals and carbon in water, pulverizing and drying them to prepare nanometal-doped carbon; (b) swelling and dissolving the hydrophilic polymer in water; (c) mixing the nanometal-doped carbon of step (a) and the hydrophilic polymer solution of step (b); (d) adding a crosslinking agent to the mixture of step (c), mixing, and reacting to prepare a polymer polymer; (e) preparing a conductive electrolyte by adding and reacting a conductive solution to the polymer polymer; And (f) drying the conductive electrolyte to form a paste, and then coating it on an electrode substrate, curing and coating it.

Here, in the step (a), the pulverization may be performed for 8 to 16 hours at room temperature of 25 to 30°C, and drying may be performed at a temperature of 10 to 100°C for 10 to 24 hours.

And, in the step (a), the nanometal and carbon may be mixed in a weight ratio of 1:1 to 10.

In addition, the nanometals are tin (Sn), zinc (Zn), titanium (Ti), tungsten (W), indium (In), nickel (Ni), iron (Fe), copper (Cu), cobalt (Co) , Silver (Ag), vanadium (V), and may be one selected from oxides thereof.

Moreover, the expansion and dissolution in step (b) may be carried out for 12 to 36 hours at a temperature of 20 to 60°C.

In addition, the hydrophilic polymer may be one selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), and combinations thereof.

In addition, the mixing in step (c) may be carried out for 10 to 24 hours at a temperature of 20 to 60 ℃.

And, the mixing and reaction in the step (d) is carried out for 10 to 24 hours at a temperature of 20 to 60 °C, and the crosslinking agent is sodium salt of m-benzenedisulfonic acid, sodium salt of p-styrenesulfonic acid, polyacrylic acid and these It may be one type selected from a combination of.

In addition, in step (e), the polymer polymer and the conductive solution may be mixed in a weight ratio of 5 to 7: 3 to 5.

In addition, the conductive solution may contain a solvent and a conductive polymer, and the solvent and the conductive polymer may be blended in a weight ratio of 1 to 20: 0.05 to 1.

At this time, the conductive polymer is one selected from polyaniline, polypyrrole, polythiophene, and combinations thereof, and the solvent is methyl ethyl keton, chloroform, Dichloromethane, Nmethylpyrrolidinone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), t-butyl alcohol, isopropyl alcohol (isopropylalcohol, iPA, 2-propanol), benzyl alcohol, tetrahydrofuran (THF), ethyl acetate, butyl acetate, propylene glycol diacetate, A number of days selected from propylene glycol methyl ether acetate (PGMEA), acetonitrile, trifluoroacetonitrile, dimethylacetamide (DMAC), and combinations thereof have.

In addition, in the step (f), drying may be performed at a temperature of 30 to 60°C for 1 to 3 hours, and curing may be performed at a temperature of 100 to 200°C for 10 to 200 minutes.

The moisture sensitive membrane for a humidity sensor of the present invention can produce a polymer electrolyte type moisture sensitive membrane by appropriately adding and mixing chemical organic/inorganic elements necessary for improving the properties of the sensor, and changing the physical properties of the sensor. It is also excellent.

The moisture sensitive film for a humidity sensor according to the present invention includes carbon doped with nanometals, so that the physical and chemical adsorption of hydroxyl groups on the surface is smooth, so that sensitivity, linearity, and reaction speed can be improved, and the electrical resistance of the moisture sensitive film can be reduced. There is an advantage that can be applied to electronic circuits and the like.

In addition, the moisture-sensitive film for a humidity sensor according to the present invention has advantages in that it is easy to process, as well as excellent in moisture detection characteristics and durability by applying a hydrophilic polymer and a nanometal-doped carbon and a conductive polymer together.

1 is a process chart showing a method of manufacturing a humidity sensor for a humidity sensor according to the present invention.
2 is a plan view showing a configuration example of an electrode substrate and a detection layer of the humidity sensor of the present invention.
3 is a diagram schematically showing a state in which water molecules are adsorbed on the surface of a metal or metal oxide.
4 is a diagram showing impedance characteristics according to humidity in a humidity sensor equipped with a moisture-sensitive membrane.

The above objects, other objects, features, and advantages of the present invention will be easily understood through the following preferred embodiments related to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be implemented in various different forms. In addition, parts not related to the present invention in the drawings are omitted to clarify the description of the present invention, and like reference numerals are attached to similar parts throughout the specification.

The moisture sensitive film for a humidity sensor according to the present invention includes 5 to 20% by weight of carbon doped with nanometals, 10 to 40% by weight of a hydrophilic polymer, 0.01 to 10% by weight of a crosslinking agent, and 30 to 50% by weight of a conductive polymer.

In the nanometal-doped carbon, the nanometal exists in a form deposited or supported in a plurality of pores of the carbon, and the nanometal is tin (Sn), zinc (Zn), titanium (Ti), tungsten (W), One selected from indium (In), nickel (Ni), iron (Fe), copper (Cu), cobalt (Co), silver (Ag), vanadium (V) and oxides thereof, preferably tin oxide ( It _{may be one selected from SnO 2} ), indium (In), tin (Sn), and oxides thereof.

The hydrophilic polymer is one selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), and combinations thereof, preferably polyvinyl alcohol. , PVA). For example, when applied to a humidity sensor, polyvinyl alcohol (PVA) is easily attacked by moisture, resulting in poor durability and very high impedance. Therefore, in the present invention, a conductive polymer and carbon with a large specific surface area doped with a nanometal were applied together.

The crosslinking agent may be one selected from the sodium salt of m-benzenedisulfonic acid (MBDS), the sodium salt of p-styrenesulfonic acid (PSSA), polyacrylic acid (PA), and combinations thereof.

The conductive polymer is 1 selected from polyaniline, polypyrrole, polythiophene, and combinations thereof, preferably polyaniline, polypyrrole, and combinations thereof. It can be a bell.

In the present invention, sodium salt of m-benzenedisulfonic acid (MBDS), sodium salt of p-styrenesulfonic acid (PSSA), polyacrylic acid (PA), and combinations thereof in a mixture of nanometal or nanometal-doped carbon and hydrophilic polymer It is characterized in that one selected from is mixed with a conductive polymer while being polymerized. Such a moisture-sensitive membrane for a humidity sensor has an advantage of excellent moisture detection characteristics and durability while maintaining the humidity sensing properties and processing ease of the hydrophilic polymer by applying a hydrophilic polymer and a nanometal-doped carbon and a conductive polymer together. By including nanometal-doped carbon, the physical and chemical adsorption of hydroxyl groups on the surface is smooth, so that sensitivity, linearity, and reaction speed can be improved, and the electrical resistance of the moisture sensitive film can be lowered, making it very suitable for electronic circuits. . In addition, durability against moisture is improved, and the detection circuit can be applied simply by a voltage division method.

Hereinafter, a method of manufacturing a humidity sensor for a humidity sensor according to the present invention will be described in detail with reference to embodiments of the present invention and drawings for explaining the same.

1 is a process chart showing a method of manufacturing a humidity sensor for a humidity sensor of the present invention.

In the method of manufacturing a moisture-sensitive film for a humidity sensor according to an embodiment of the present invention, first, nanometals and carbon are mixed in water, and then pulverized and dried to produce nanometal-doped carbon (S10).

After mixing and dispersing nanometals and carbon in water at a 1:1 to 10 weight ratio, Ball mill, Attrition mill, Jet mill, rotating at room temperature at 25 to 30℃ Grinding for 8 to 16 hours, preferably 10 to 14 hours using any one of a rotary mill and a vibration mill, and then 10 to 100°C, preferably 30 to 70 Drying can be carried out for 10 to 24 hours at a temperature of °C. The nano-metal may be deposited or supported in a plurality of pores of carbon by the pulverization and drying as described above, thereby leading to an effect of further improving the moisture adsorption and desorption properties.

The nanometals are tin (Sn), zinc (Zn), titanium (Ti), tungsten (W), indium (In), nickel (Ni), iron (Fe), copper (Cu), cobalt (Co), and silver. (Ag), vanadium (V) and one selected from oxides thereof, preferably tin oxide (SnO ₂ ), indium (In), tin (Sn), and may be one selected from oxides thereof, the Carbon is activated charcoal, ie activated carbon, which removes hydrocarbons and increases adsorption capacity, and may contain a large number of pores. Carbon may be in the form of activated carbon or activated carbon powder, and may have a specific surface area of 500 m ² /g or more, and a particle size of 10 μm or less. If the ratio of such carbon is less than 10, the electric resistance is large, and the moisture-sensitive characteristics such as sensitivity and reproducibility may be poor, and if it exceeds 50, the electric resistance is too low, the durability of the material is insufficient, and the moisture-sensitive characteristics may be deteriorated. .

If the pulverization time is less than 8 hours, it is difficult to evenly disperse the nanometals and carbon, and if it exceeds 16 hours, it is difficult to handle due to being crushed, and the amount of loss dispersed in the air may increase. If the drying temperature is less than 10°C, the time required for drying may be lengthened, resulting in poor work efficiency. If it exceeds 100°C, the synergistic effect due to higher temperatures than necessary is not very large, and adversely affects the physical properties of the metal. It is not desirable because it can give.

After the pulverization and drying are completed, the step of selecting only carbon doped with nanometals having a particle size range of 1 to 10 μm using a sieve may be further performed, and carbon doped with nano metals exceeding the range of 10 μm may be 1 Further grinding can be carried out to have a particle size range of ~10 μm. As the screening step is further performed as described above, the reaction with the conductive solution to be described later or moisture adsorption and desorption properties may be further improved.

Then, the hydrophilic polymer is expanded and dissolved in water (S20).

5 to 15 parts by weight, preferably 7 to 12 parts by weight of a hydrophilic polymer is added to 100 parts by weight of water at a temperature of 20 to 60°C, preferably 25 to 30°C for 12 to 36 hours, preferably 10 to It can be dissolved for 25 hours to prepare a hydrophilic polymer solution.

The hydrophilic polymer is one selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), and combinations thereof, preferably polyvinyl alcohol, PVA).

Then, the nano-metal-doped carbon and the hydrophilic polymer solution are mixed (S30).

After adding 5 to 30 parts by weight of the nanometal-doped carbon prepared in step S10 to 100 parts by weight of the hydrophilic polymer solution prepared in step S20, 20 to 60°C, preferably 25 to 30, using a stirrer. Mixing may be carried out by stirring for 10 to 24 hours under room temperature conditions of °C.

Thereafter, a crosslinking agent is added to the mixture, mixed and reacted to prepare a polymer polymer (S40).

After adding a crosslinking agent to the mixture of the nanometal-doped carbon and hydrophilic polymer solution in step S30, the crosslinking agent is stirred for 10 to 24 hours at room temperature conditions of 20 to 60°C, preferably 25 to 30°C. Allows the mixture to be crosslinked. If the temperature is less than 20° C., the polymerization rate may be slow and the reaction may take a long time. If it exceeds 60° C., the reaction rate may be high, but it may be difficult to uniformly perform polymerization.

The crosslinking agent may be one selected from the sodium salt of m-benzenedisulfonic acid (MBDS), the sodium salt of p-styrenesulfonic acid (PSSA), polyacrylic acid (PA), and combinations thereof, for example, m -When using the sodium salt of benzenedisulfonic acid (MBDS) or the sodium salt of p-styrenesulfonic acid (PSSA), 0.06 to 1 parts by weight, preferably 0.1 to 0.2 parts by weight, based on 100 parts by weight of the polymer mixture In the case of using polyacrylic acid (PA), 0.1 to 0.5 parts by weight, preferably 0.2 to 0.3 parts by weight, based on 100 parts by weight of the polymer mixture may be added, and this content range is a crosslinking reaction according to the type of crosslinking agent. Is the optimal condition.

Then, a conductive solution is added and reacted to the polymer polymer to prepare a conductive electrolyte (S50).

After mixing the polymer polymer and the conductive solution prepared in step S40 in a weight ratio of 5 to 7: 3 to 5, preferably 6: 4, and reacting at a temperature of 40 to 60 °C for 10 to 24 hours, a conductive composite polymer Phosphorus conductive electrolytes can be prepared. If the ratio of the conductive solution is less than 3, the electrical resistance of the moisture-sensitive material may be too high, and if it exceeds 6, the electrical resistance is too high, which may be detrimental to the moisture-sensitive property.

In the present invention, the conductive solution may be a mixture of a solvent and a conductive polymer, and in this case, the solvent and the conductive polymer may be blended in a weight ratio of 1 to 20: 0.05 to 1. This is not preferable because if the content ratio of the solvent is less than 1, the blendability and uniformity of physical properties may deteriorate, and if it exceeds 20, the time required for manufacturing may be long and waste of various materials may occur.

The solvent is methyl ethyl keton, chloroform, dichloromethane, methylpyrrolidinone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide, DMF), t-butyl alcohol, isopropylalcohol (iPA, 2-propanol), benzyl alcohol, tetrahydrofuran (THF), ethyl acetate, Butyl acetate, propylene glycol diacetate, propylene glycol methyl ether acetate (PGMEA), acetonitrile, trifluoroacetonitrile, dimethylacetate It may be one selected from amide (dimethylacetamide, DMAC), and combinations thereof, preferably chloroform.

The conductive polymer is 1 selected from polyaniline, polypyrrole, polythiophene, and combinations thereof, preferably polyaniline, polypyrrole, and combinations thereof. It may be a species, but is not limited thereto, and any material having conductivity is not limited to its use.

Finally, the conductive electrolyte is dried and pasted, and then cured and coated by coating it on the electrode substrate (S60).

The conductive electrolyte prepared in step S50 is dried and evaporated at a temperature of 30 to 60° C., preferably 35 to 50° C. for 1 to 3 hours to form a paste, which is then subjected to painting, dip, spray, or spin coating. Select any one method and apply it on the aluminum insulating substrate 1 on which the pair of comb-shaped gold or platinum electrodes 2 is formed as shown in FIG. 2 to 100 to 200°C, preferably 140 to 160 Curing and coating for 10 minutes to 200 minutes, preferably 120 minutes to 180 minutes at a temperature of ℃ to form the moisture-sensitive film (3). If the drying temperature is less than 30°C, the solution is difficult to dry, so it may take a long time to prepare the paste formulation. If it exceeds 60°C, the synergistic effect may not be so great due to heating more than necessary. When the curing temperature is less than 100° C., curing may not be sufficient or it may take a long time, and when it exceeds 200° C., crystals may become coarse and large, and it may be difficult to secure sufficient hardness.

When the curing and coating step (S60) as described above is completed, a humidity sensor (S70) provided with a moisture-sensitive film is obtained. The humidity sensor has a pair of comb-shaped electrodes 2 on the insulating substrate 1, and the pair of comb-shaped electrodes 2 are engaged by a gap of a predetermined distance so that the humidity sensor is placed on the insulating substrate 1. It is disposed, and a moisture-sensitive film 3 may be installed on the insulating substrate 1 and the electrode 2.

In the present invention, the material and size of the insulating substrate is not particularly limited as long as it is commonly used, but as an example, the insulating substrate may be alumina or silicon having a size of 2.5×2.5 mm and a thickness of 0.25 to 0.42 mm. There is no particular limitation as long as the material and size of the electrode are also commonly used, but may be formed of gold or platinum that conducts electricity well by conventional methods such as screen printing and photolithography, and the contact area with the moisture sensitive film is maximized. In order to intersect with each other at intervals of 0.2 mm, it is preferable to form four or more, and each width is preferably set to 0.2 to 0.3 mm. When power is applied between both electrodes in the above-described configuration, the humidity can be detected by changing the output voltage due to the change in resistance and impedance according to the humidity of the moisture sensitive film.

The humidity sensor of the present invention is provided with a moisture-sensitive membrane further including carbon doped with nanometals in addition to the hydrophilic polymer. As shown in FIG. 3, moisture absorbed by the polymer polymer of the moisture-sensitive membrane helps decomposition of the ionic material and prevents usable ions. As the number is increased, in the end, the resistivity of the moisture sensitive film can be greatly reduced. In other words, when moisture is chemically adsorbed on the surface of the moisture-sensitive film, conductive ions or electrons of the material become more free and the resistance of the humidity sensor may be reduced.

Example 1. Manufacture of humidity sensor

_{In 100 ml of water, 10 mg of SnO 2} having an average particle diameter of 0.1 μm and 50 mg of carbon were mixed, pulverized for 12 hours with a roll mill, and dried at 50° C. to prepare carbon powder. Then, 1 g of PVA was added to 10 ml of water and expanded at room temperature for 24 hours. When the PVA was completely dissolved the next day, it was mixed with the carbon powder. 150 mg of MBDS was dissolved in 2 ml of water, and this was added to the mixture for polymerization to prepare a polymer. Then, 20 mg of polyaniline was completely dissolved in 20 ml of chloroform, and this was added to the polymer, followed by mixing thoroughly with a roll mill at 50° C. for 5 hours. Then, after drying in a paste state, it is applied on alumina and silicon substrates (size 2.5mm×2.2mm×0.381mm) with electrodes formed of gold or platinum, and cured and coated at 150℃ for 3 hours to provide humidity with a moisture-sensitive film. A sensor was obtained.

Example 2. Manufacture of humidity sensor

A humidity sensor of Example 2 was obtained in the same manner as in Example 1, except that Fe instead of _{SnO 2} as a nano metal and polypyrrole instead of polyaniline as a conductive polymer was used.

Example 3. Manufacture of humidity sensor

A humidity sensor of Example 3 was obtained in the same manner as in Example 1, except that In was used instead of _{SnO 2} as a nanometal.

Experimental Example 1. Moisture Characteristics

Experiments were conducted as follows in order to confirm the humidity-sensitive characteristics of the humidity sensors manufactured according to Examples 1 to 3 according to the present invention.

Experiments were conducted using a constant temperature and humidity tank, and humidity was controlled by mixing dry air with a humidity of 5% and a humidifier at a humidity of less than 30%, and a humidifier was used to control the humidity at a humidity of 30% or less. I did. The resistance value of the humidity sensor was measured for each 10% humidity with a precision resistance meter corresponding to the humidity indication of the calibrated digital hygrometer.

The results are shown in FIG. 4.

Referring to FIG. 4, the measured values of Examples 1 to 3 were similar, but in particular, the resistance value, moisture-sensitive property, and resistance change of Example 1 using _{SnO 2 as a nanometal were generally compared to those of Examples 2 and 3.} It was able to confirm the excellence.

Although the invention made by the present inventor has been described in detail according to the above embodiment, the invention is not limited to the above embodiment, and it goes without saying that the invention can be changed in various ways without departing from the gist.

1: substrate
2: electrode
3: moisture barrier

Claims (17)

Including 5 to 20% by weight of carbon having a plurality of pores doped with a nanometal, 10 to 40% by weight of a hydrophilic polymer, 0.01 to 10% by weight of a crosslinking agent, and 30 to 50% by weight of a conductive polymer,
The moisture sensor for a humidity sensor in which the nanometal is deposited or supported in a plurality of pores of carbon.
The method of claim 1,
The nanometals are tin (Sn), zinc (Zn), titanium (Ti), tungsten (W), indium (In), nickel (Ni), iron (Fe), copper (Cu), cobalt (Co), and silver. (Ag), vanadium (V), and a moisture-sensitive film for a humidity sensor that is one type selected from oxides thereof.
The method of claim 1,
The hydrophilic polymer is one selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), and a combination thereof.
The method of claim 1,
The crosslinking agent is one selected from the sodium salt of m-benzenedisulfonic acid, the sodium salt of p-styrenesulfonic acid, polyacrylic acid, and a humidity sensor for a humidity sensor.
The method of claim 1,
The conductive polymer is one selected from polyaniline, polypyrrole, polythiophene, and a combination thereof, for a humidity sensor.
(a) mixing the nanometal and carbon having a plurality of pores in water, pulverizing and drying, and doping so that the nanometal is deposited or supported in the plurality of pores of the carbon;
(b) swelling and dissolving the hydrophilic polymer in water;
(c) mixing the carbon having a plurality of pores doped with the nanometal of the step (a) and the hydrophilic polymer solution of the step (b);
(d) adding a crosslinking agent to the mixture in step (c), mixing, and reacting to prepare a polymer polymer;
(e) preparing a conductive electrolyte by adding and reacting a conductive solution to the polymer polymer; And
(f) drying the conductive electrolyte, forming a paste, and then coating it on an electrode substrate, curing and coating it.
The method of claim 6,
In the step (a), the pulverization is carried out at room temperature of 25 to 30° C. for 8 to 16 hours, and drying is performed at a temperature of 10 to 100° C. for 10 to 24 hours.
The method of claim 6,
In the step (a), the nano-metal and the carbon having a plurality of pores are mixed in a weight ratio of 1:1 to 10. A method of manufacturing a moisture-sensitive membrane for a humidity sensor.
The method of claim 6,
The nanometals are tin (Sn), zinc (Zn), titanium (Ti), tungsten (W), indium (In), nickel (Ni), iron (Fe), copper (Cu), cobalt (Co), and silver. (Ag), vanadium (V), and a method for producing a moisture-sensitive film for a humidity sensor, which is one selected from oxides thereof.
The method of claim 6,
In the step (b), the expansion and dissolution are carried out at a temperature of 20 to 60°C for 12 to 36 hours.
The method of claim 6,
The hydrophilic polymer is selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), and a combination thereof.
The method of claim 6,
The mixing in step (c) is a method of manufacturing a moisture-sensitive membrane for a humidity sensor that is carried out for 10 to 24 hours at a temperature of 20 to 60 °C.
The method of claim 6,
The mixing and reaction in the step (d) is carried out for 10 to 24 hours at a temperature of 20 to 60°C, and the crosslinking agent is sodium salt of m-benzenedisulfonic acid, sodium salt of p-styrenesulfonic acid, polyacrylic acid, and combinations thereof. Method for producing a moisture-sensitive film for a humidity sensor, which is one type selected from.
The method of claim 6,
In the step (e), the polymer polymer and the conductive solution are mixed in a weight ratio of 5 to 7: 3 to 5;
The method of claim 14,
The conductive solution contains a solvent and a conductive polymer, and the solvent and the conductive polymer are blended in a weight ratio of 1-20: 0.05-1.
The method of claim 15,
The conductive polymer is one selected from polyaniline, polypyrrole, polythiophene, and combinations thereof,
The solvent is methyl ethyl keton, chloroform, dichloromethane, methylpyrrolidinone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide, DMF), t-butyl alcohol, isopropylalcohol (iPA, 2-propanol), benzyl alcohol, tetrahydrofuran (THF), ethyl acetate, Butyl acetate, propylene glycol diacetate, propylene glycol methyl ether acetate (PGMEA), acetonitrile, trifluoroacetonitrile, dimethylacetate Amide (dimethylacetamide, DMAC), and a method for producing a moisture-sensitive membrane for a humidity sensor that is one kind selected from a combination thereof.
The method of claim 6,
In the step (f), drying is performed at a temperature of 30 to 60°C for 1 to 3 hours, and curing is performed at a temperature of 100 to 200°C for 10 to 200 minutes.

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