CN112611787A - High-molecular resistance type humidity sensitive element and preparation method thereof - Google Patents
High-molecular resistance type humidity sensitive element and preparation method thereof Download PDFInfo
- Publication number
- CN112611787A CN112611787A CN202011468762.6A CN202011468762A CN112611787A CN 112611787 A CN112611787 A CN 112611787A CN 202011468762 A CN202011468762 A CN 202011468762A CN 112611787 A CN112611787 A CN 112611787A
- Authority
- CN
- China
- Prior art keywords
- humidity
- electrodes
- interdigital
- interdigital electrode
- resistance type
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
- G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
- G01N27/121—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid for determining moisture content, e.g. humidity, of the fluid
Abstract
The invention relates to a high-molecular resistance type humidity sensitive element which is characterized by comprising a packaging shell, a base body, a humidity sensitive film, interdigital electrodes and pins, wherein the base body is a humidity sensitive sensing base body, and the humidity sensitive films are arranged on the surfaces of the interdigital electrodes and the base body; the interdigital electrodes include transverse electrodes and longitudinal electrodes. According to the invention, the organic polymer material is compounded by adopting a multilayer brushing technology, the resistance of the polymer resistance type humidity sensor in a low-humidity environment is obviously reduced, the sensitive detection of the low-humidity environment is realized, the deliquescence resistance of the film is improved by doping cellulose, in addition, the precision of screen printing based on a single screen is lower, the pattern of an interdigital electrode is split into a transverse electrode part and a longitudinal electrode part, the preparation precision of the interdigital electrode is improved by adopting a multi-screen printing technology, the adhesion between the electrode and a substrate is enhanced by copper doping of conductive ink, and the humidity sensitive characteristic with high sensitivity, good linearity, high response speed and high reliability is obtained.
Description
Technical Field
The invention relates to a high-molecular resistance type humidity sensitive element and a preparation method thereof.
Background
The humidity sensor is used as an important information acquisition element for moisture detection of the hygrometer and is widely applied to industrial production and daily life. Humidity sensors can be classified into organic polymer type and semiconductor ceramic type based on humidity sensing materials, wherein organic polymers are widely researched due to the advantages of wide response range, short response time, small humidity stagnation, simple preparation, low cost and the like. High molecular polymer can be divided into resistance type and capacitance type according to the response characteristic, and the high molecular resistance type humidity sensor is a type which is developed rapidly at present due to the excellent comprehensive performance, and generally adopts an interdigital electrode structure, and a humidity sensing material is uniformly coated on an interdigital electrode and a substrate, and the high molecular humidity sensitive resistor can be divided into three types according to a conductive mechanism: 1. electronic types based on conductive powder (metal, graphite)/polymer materials, also called dilatant; 2. ionic based on polyelectrolyte materials; 3. it is a composite type integrating ion and electronic conductors. The ionic type humidity-sensitive resistor based on polyelectrolyte is a common type, has the advantages of quick response, high sensitivity, small volume, simple preparation method, low price and the like, and is applied to the fields of meteorology, industry, food and the like.
The polyelectrolyte humidity-sensitive material is a hydrophilic polymer containing dissociable groups, and after the material adsorbs moisture in the environment, ions which move freely are dissociated, so that the conductivity is increased, and the detection of the environment humidity can be realized by measuring the change of the conductivity. Polyelectrolyte materials typically have a hydrophobic polymer (e.g., alkyl, phenyl, etc.) as a backbone with pendant groups containing strongly polar groups, such as: -NH4Cl、-SO3Na、-NH2And the like. In a humid environment, water molecules are adsorbed by polar groups on the surface of the material, and the quantity of the adsorbed water molecules is correspondingly changed along with the increase of the humidity of the environment, so that the adsorbed water is gradually condensed to form liquid water, namely electrolyte solution with the property of a conductive channel. With the increase of the humidity, the polymer swells, the internal free volume increases, the current carriers increase, meanwhile, the activation energy of the counter ions of the high molecular polyelectrolyte is reduced, the mobility is improved, and the resistance of the material is reduced. On the contrary, when the ambient humidity becomes small, water molecules are removed from the ionic polymer, so that the resistance of the material is increased. By measuring the change of the resistance value, the relative humidity in the environment can be monitored.
However, the sensors also have the defects that when the polymer polyelectrolyte material is used for a long time in a high-temperature high-humidity environment, the polymer polyelectrolyte material is in a state similar to dissolved water, and when the polymer polyelectrolyte material is seriously used, a humidity-sensitive film has a flow-moving phenomenon, so that the stability of the polymer polyelectrolyte material is seriously influenced. Therefore, the key point of the current research on the polymer resistance type humidity sensor is how to improve the water resistance and long-term stability of the humidity sensor, and the key point is that the polymer polyelectrolyte material is not dissolved in water any more. To solve this problem, methods of copolymerization with hydrophobic materials, crosslinking, grafting, interpenetrating networks (IPNs), adding protective films, and the like are widely used. In addition, the high molecular polyelectrolyte material has the problems of too high impedance under the condition of too low humidity, incapability of measurement and large wet retardation, and the impedance of a humidity sensor needs to be reduced for realizing the measurement in a low-humidity environment, and the most common method is to compound the polyelectrolyte and an intrinsic conductive material, such as polypyrrole, polyaniline, carbon black, a carbon nano tube and the like; in order to improve the response characteristic of the sensor, the humidity sensor needs to reduce the wet hysteresis, and the method can be realized by introducing hydrophobic groups into polymers, compounding the polymers with the hydrophobic polymers and the like.
The polymer resistance type humidity sensitive material has poor conductivity in a low-humidity environment, and the resistance value is too high to be measured; the water resistance is poor in a high-humidity environment, and the problems of response drift, even damage and failure occur.
Based on the problems of poor water resistance, response drift and even damage failure of a high-molecular resistance type humidity-sensitive material in a high-humidity environment, the existing solution is to copolymerize, crosslink, graft and Interpenetrating Polymer Networks (IPN) with a hydrophobic material, add a protective film and the like, which means that a polymer material needs to be pretreated before a humidity-sensitive film is coated, the conditions of high temperature and long-time reaction are usually needed, and meanwhile, a humidity-sensitive material preparation process is added, so that the production flow is more complicated, the controllability of the preparation process is poor, and the consistency of a humidity-sensitive element is lower.
Based on the problems that the high-molecular resistance type humidity-sensitive material has poor conductivity and too high resistance value under a low-humidity environment and is difficult to measure, the problems are usually solved by adopting methods of doping inorganic conductive components such as carbon black, carbon nanotubes and the like, and although the impedance of the material under low humidity is reduced, the defects of low humidity sensitivity, poor linearity of a response curve and the like exist. In addition, the simple blending system is not favorable for the long-term stability and consistency of the humidity sensitive element. Besides inorganic conductive materials, organic high-molecular conductive polymers such as polypyrrole and polyaniline are effective means for improving the conductivity of the materials, compared with inorganic materials, the organic high-molecular conductive polymers are better in compatibility with polyelectrolyte materials, chemical modification is easy to achieve, the intrinsic conductive polymers can be introduced into a polyelectrolyte system by chemical methods such as copolymerization or grafting, the humidity-sensitive response of the materials under low humidity is effectively improved, meanwhile, the long-term stability of the materials is guaranteed, and the processing cost is also improved.
At present, the complete pattern of an interdigital electrode is printed on a silk screen in the preparation of the interdigital electrode by adopting the silk screen printing, so that the minimum precision of the electrode preparation is influenced, because the optimal scraping direction is longitudinal when preparing a transverse electrode part in the interdigital electrode, and the longitudinal electrode part is the opposite. In addition, the adhesion between the interdigital electrode printed by using the common ink and the substrate is not firm, and the interdigital electrode falls off when the humidity sensitive layer is thick or the air humidity is high.
Disclosure of Invention
The invention aims to overcome the defects and provide a high-molecular resistance type humidity sensitive element which is used for solving the problems of overhigh low-humidity resistance and high humidity and deliquescence of a humidity sensitive material and has high sensitivity, good linearity, high response speed and high reliability and a preparation method thereof.
The purpose of the invention is realized as follows:
a macromolecule resistance type humidity sensitive element comprises a packaging shell, a base body, a humidity sensitive film, interdigital electrodes and pins, wherein the base body is a humidity sensitive sensing base body and is arranged in the packaging shell; the interdigital electrodes include transverse electrodes and longitudinal electrodes.
Preferably, the substrate is ceramic, the interdigital electrodes are made of conductive ink, a plurality of pairs of interdigital electrodes are screen-printed on the surface of the ceramic substrate, pins are welded on the interdigital electrodes, the humidity sensing film is made of multiple layers of humidity sensing materials, the humidity sensing materials are polyelectrolyte organic matters, and the thickness of the humidity sensing film is 30-34 micrometers.
Preferably, the finger width of the interdigital electrode is 0.2-0.25mm, the inter-finger distance is 0.15-0.2mm, and the thickness is 10-15 μm.
Preferably, the preparation method of the high-molecular resistance type humidity sensitive element comprises two parts of preparation of an interdigital electrode and preparation of a humidity sensitive film;
polyelectrolyte organic matters of the humidity-sensitive film comprise poly (4-sodium styrene sulfonate), hydroxyethyl cellulose and polydiene dimethyl ammonium chloride solution;
firstly preparing an interdigital electrode, and then arranging a humidity-sensitive film on the surfaces of a substrate and the interdigital electrode to form a high-molecular composite humidity-sensitive film.
As a preference for the use of the composition,
the preparation process of the interdigital electrode is as follows:
the first step is as follows: preparing the interdigital electrode by adopting a screen printing technology, and printing ink: the mass ratio of the copper powder is (8-10): 1, preparing the printing ink into paste;
the second step is that: then, injecting the paste onto a first screen printing plate with partial interdigital electrode patterns, wherein the patterns of the first screen printing plate correspond to the printing transverse electrodes, scraping the paste under the conditions of an inclination angle of 35-45 degrees and a pressure of 5-15 newtons, manufacturing the transverse electrodes and drying;
the third step: aligning the electrode dried after the second step of printing with a second silk screen plate with partial interdigital electrode patterns, wherein the patterns of the second silk screen plate correspond to the printed longitudinal electrodes, scraping paste under the same condition, printing the longitudinal electrodes and drying;
the fourth step: repeating the operations of the second step and the third step once in sequence;
the fifth step: and injecting paste of the silver-palladium alloy onto the silk screen with the shape of the pad to print the pad, and then drying.
As a preferable, the ink: the mass ratio of the copper powder is 9: 1, in a ratio of 1.
Preferably, the preparation process of the humidity-sensitive film is as follows:
the first step is as follows: mixing poly (4-sodium styrene sulfonate), deionized water and hydroxyethyl cellulose according to the weight ratio of (13-17): 100: (13-17) mixing according to the weight ratio, and fully stirring to completely dissolve the powdery material to obtain a first solution;
the second step is that: taking a proper amount of polydiene dimethyl ammonium chloride solution as a second solution;
the third step: and (3) uniformly coating the first solution on the surfaces of the substrate and the interdigital electrode by using a dispenser, standing at room temperature for 3-5 minutes, and uniformly coating the second solution after drying.
The fourth step: sintering and curing the humidity sensitive element in a muffle furnace to form a humidity sensitive film with the thickness of 30-34 microns on the surface, wherein the temperature rise program is as follows: the temperature is first reached to 90-110 ℃ from room temperature over 30-50 minutes and then maintained for 90 minutes.
As a preferred choice, poly (sodium 4-styrenesulfonate) has a MW (molecular weight) of 70000, which is a powder material;
the hydroxyethyl cellulose has MW 90000;
the weight ratio of the poly (sodium 4-styrene sulfonate), the deionized water and the hydroxyethyl cellulose is preferably 17: 100: 13.
as a preference, the polydiene dimethyl ammonium chloride solution has two specifications:
the first specification is polydienedimethylammonium chloride at 20% by weight in water, MW 400000-500000, and viscosity at 25 ℃ of 800-1000 cP.
The first specification is polydienedimethylammonium chloride in water at a weight ratio of 35%, MW < 100000, viscosity at 25 ℃ of 100-200 cP.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, the organic polymer material is compounded by adopting a multilayer brushing technology, the resistance of the polymer resistance type humidity sensor in a low-humidity environment is obviously reduced, the sensitive detection of the low-humidity environment is realized, the deliquescence resistance of the film is improved by doping cellulose, in addition, the precision of screen printing based on a single screen is lower, the pattern of an interdigital electrode is split into a transverse electrode part and a longitudinal electrode part, the preparation precision of the interdigital electrode is improved by adopting a multi-screen printing technology, the adhesion between the electrode and a substrate is enhanced by copper doping of conductive ink, and the humidity sensitive characteristic with high sensitivity, good linearity, high response speed and high reliability is obtained.
Drawings
FIG. 1 is a schematic structural diagram of a polymer resistor type humidity sensor.
Fig. 2 is a graph showing the relative humidity-resistance characteristic according to the present invention.
FIG. 3 is a graph comparing relative humidity and resistance values of examples.
Wherein:
the packaging structure comprises a packaging shell 1, a base body 2, a humidity sensing film 3, interdigital electrodes 4 and pins 5.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, the polymer resistance type humidity sensitive element according to the present invention includes a package shell 1, a substrate 2, a humidity sensitive film 3, an interdigital electrode 4 and pins 5, where the substrate 2 is a humidity sensitive sensing substrate, the substrate 2 is disposed in the package shell 1, the interdigital electrode 4 is disposed on the substrate 2, a leading-out end of the interdigital electrode 4 is connected to the two pins 5, the pins 5 extend out of the package shell 1, and the humidity sensitive film 3 is disposed on the surfaces of the interdigital electrode 4 and the substrate 2. The interdigital electrodes include transverse electrodes and longitudinal electrodes.
Preferably, the substrate 2 is ceramic, the conductive ink is used as a material of the interdigital electrode 4, a plurality of pairs of interdigital electrodes 4 are screen-printed on the surface of the ceramic substrate 2, the pins 5 are welded on the interdigital electrodes 4, the humidity sensing film 3 is composed of a plurality of layers of humidity sensing materials, the humidity sensing materials are polyelectrolyte organic matters, the polyelectrolyte organic matters comprise poly (4-sodium styrene sulfonate), hydroxyethyl cellulose and polydiene dimethyl ammonium chloride solution, and the humidity sensing materials are coated on the surfaces of the substrate 2 and the interdigital electrodes 4 by adopting a dispensing technology to form the macromolecular composite humidity sensing film. As a preferred moisture-sensitive material, there are two layers, a first moisture-sensitive material layer containing poly (4-sodium styrene sulfonate) and hydroxyethyl cellulose and a second moisture-sensitive material layer containing poly (diallyldimethylammonium chloride).
The preparation method of the high-molecular resistance type humidity sensitive element comprises two parts of preparation of an interdigital electrode and preparation of a humidity sensitive film.
The preparation process of the interdigital electrode is as follows:
the first step is as follows: preparing the interdigital electrode by adopting a screen printing technology, and printing ink: the mass ratio of the copper powder is (8-10): 1, preparing the printing ink into paste; as a preferable, the ink: the mass ratio of the copper powder is 9: 1;
the second step is that: then, injecting the paste onto a first screen printing plate with partial interdigital electrode patterns, wherein the patterns of the first screen printing plate correspond to the printing transverse electrodes, scraping the paste under the conditions of an inclination angle of 35-45 degrees and a pressure of 5-15 newtons, manufacturing the transverse electrodes and drying;
the third step: aligning the electrode dried after the second step of printing with a second silk screen plate with partial interdigital electrode patterns, wherein the patterns of the second silk screen plate correspond to the printed longitudinal electrodes, scraping paste under the same condition, printing the longitudinal electrodes and drying;
the fourth step: repeating the operations of the second step and the third step once in sequence;
the fifth step: and injecting paste of the silver-palladium alloy onto a silk screen with a pad shape for printing the pad, and then drying to obtain the interdigital electrode with the finger width of 0.2-0.25mm, the inter-finger distance of 0.15-0.2mm and the thickness of 10-15 mu m.
Wherein, the preparation process of the humidity sensitive film is as follows:
the first step is as follows: mixing poly (4-sodium styrene sulfonate), deionized water and hydroxyethyl cellulose according to the weight ratio of (13-17): 100: (13-17) mixing according to the weight ratio, and fully stirring to completely dissolve the powdery material to obtain a first solution;
as a preference, wherein:
the MW (molecular weight) of poly (4-sodium styrene sulfonate) is 70000, which is a powder material;
the hydroxyethyl cellulose has MW 90000;
the weight ratio of the poly (sodium 4-styrene sulfonate), the deionized water and the hydroxyethyl cellulose is preferably 17: 100: 13;
the second step is that: taking a proper amount of polydiene dimethyl ammonium chloride solution as a second solution;
there are two specifications:
the first specification is polydienedimethylammonium chloride at 20% by weight in water, MW 400000-500000, and viscosity at 25 ℃ of 800-1000 cP.
The first specification is polydienedimethylammonium chloride in water at a weight ratio of 35%, MW < 100000, viscosity at 25 ℃ of 100-200 cP.
The above specification is preferably the first.
The third step: and (3) uniformly coating the first solution on the surfaces of the substrate and the interdigital electrode by using a dispenser, standing at room temperature for 3-5 minutes, and uniformly coating the second solution after drying.
The fourth step: and sintering and curing the humidity sensitive element in a muffle furnace to form a humidity sensitive film with the thickness of 30-34 microns on the surface of the humidity sensitive element. The temperature raising program is set as follows: the temperature is first reached to 90-110 ℃ from room temperature over 30-50 minutes and then maintained for 90 minutes.
The electrical performance parameters of the high-molecular resistance type humidity sensitive element are as follows:
| operating voltage | 5VAC |
| Detecting frequency | 1kHz |
| Detection range | 20～90％RH |
| Detection accuracy | ±5％RH |
| Working temperature range | 0～60℃ |
| Range of characteristic impedance | 25(18.8～48.5)kΩ(60％RH，25℃) |
According to the invention, the organic polymer material is compounded by adopting a multilayer brushing technology, the resistance of the polymer resistance type humidity sensor in a low-humidity environment is obviously reduced, the sensitive detection of the low-humidity environment is realized, the deliquescence resistance of the film is improved by doping cellulose, in addition, the precision of screen printing based on a single screen is lower, the pattern of an interdigital electrode is split into a transverse electrode part and a longitudinal electrode part, the preparation precision of the interdigital electrode is improved by adopting a multi-screen printing technology, the adhesion between the electrode and a substrate is enhanced by copper doping of conductive ink, and the humidity sensitive characteristic with high sensitivity, short response time and high reliability is obtained.
Example 1: the preparation process of the interdigital electrode of the polymer resistance type humidity sensitive element is as follows:
the first step is as follows: preparing the interdigital electrode by adopting a screen printing technology, and printing ink: the mass ratio of the copper powder is 8: 1, preparing the printing ink into paste;
the second step is that: then, injecting the paste onto a first screen printing plate with partial interdigital electrode patterns, wherein the patterns of the first screen printing plate correspond to the printing transverse electrodes, scraping the paste under the conditions of an inclination angle of 35-45 degrees and a pressure of 5-15 newtons, manufacturing the transverse electrodes and drying;
the third step: aligning the electrode dried after the second step of printing with a second silk screen plate with partial interdigital electrode patterns, wherein the patterns of the second silk screen plate correspond to the printed longitudinal electrodes, scraping paste under the same condition, printing the longitudinal electrodes and drying;
the fourth step: repeating the operations of the second step and the third step once in sequence;
the fifth step: and injecting paste of the silver-palladium alloy onto a silk screen with a pad shape for printing the pad, and then drying to obtain the interdigital electrode with the finger width of 0.2-0.25mm, the inter-finger distance of 0.15-0.2mm and the thickness of 10-15 mu m.
Wherein, the preparation process of the humidity sensitive film is as follows:
the first step is as follows: mixing poly (4-sodium styrene sulfonate), deionized water and hydroxyethyl cellulose according to the weight ratio of 15: 100: 15, fully stirring to completely dissolve the powdery material to obtain a first solution;
the second step is that: taking a proper amount of polydiene dimethyl ammonium chloride solution (with a first specification) and recording as a No. two solution;
the third step: and (3) uniformly coating the first solution on the surfaces of the substrate and the interdigital electrode by using a dispenser, standing at room temperature for 3-5 minutes, and uniformly coating the second solution after drying.
The fourth step: and sintering and curing the humidity sensitive element in a muffle furnace to form a humidity sensitive film with the thickness of 30-34 microns on the surface of the humidity sensitive element. The temperature raising program is set as follows: the temperature is first reached to 90-110 ℃ from room temperature over 30-50 minutes and then maintained for 90 minutes.
Example 2: the preparation process of the interdigital electrode of the high-molecular resistance type humidity sensitive element comprises the following steps of: the mass ratio of the copper powder is adjusted to 9: except for 1, the procedure was the same as in example 1, and the process for producing a moisture-sensitive film was the same as in example 1.
Example 3: the preparation process of the interdigital electrode of the high-molecular resistance type humidity sensitive element comprises the following steps of: the mass ratio of the copper powder is adjusted to 10: except for 1, the procedure was the same as in example 1, and the process for producing a moisture-sensitive film was the same as in example 1.
Example 4: the preparation process of the interdigital electrode of the high-molecular resistance type humidity sensitive element is consistent with that of the interdigital electrode in the embodiment 2, except that the mass ratio of the poly (4-sodium styrene sulfonate), the deionized water and the hydroxyethyl cellulose in the first step is adjusted to 13: 100: except for 17, the other steps are also the same as in example 2.
Example 5: the preparation process of the interdigital electrode of the high-molecular resistance type humidity sensitive element is consistent with that of the interdigital electrode in the embodiment 2, except that the mass ratio of the poly (4-sodium styrene sulfonate), the deionized water and the hydroxyethyl cellulose in the first step is adjusted to be 17: 100: except for 13, the steps are the same as in example 2.
Example 6: the preparation process of the interdigital electrode of the high molecular resistance type humidity sensitive element is consistent with that of the embodiment 5, the preparation process of the humidity sensitive film is the same as that of the embodiment 5 except that polydiene dimethyl ammonium chloride solutions with different specifications are replaced, and the polydiene dimethyl ammonium chloride solution used in the embodiment is the second specification.
The comparison of the relative humidity-resistance characteristic curves of the above examples with each other is shown in fig. 3, and it can be seen that the humidity sensitivity, the test response time, and the analysis reliability can be calculated to be shown in table 1, and that example 5 has the humidity-sensitive characteristic of high sensitivity, short response time, and high reliability.
Note: [1] the stability refers to that the humidity sensor is placed in an environment with 60% RH and 25 ℃ for 1200h to generate relative humidity drift;
[2] the heat resistance refers to the drift of relative humidity after the humidity sensor is placed in an environment with 30% RH and 70 ℃ for 1000 h;
[3] the moisture resistance means that the humidity sensor is subjected to a drift of relative humidity after being placed in an environment of 90% RH and 40 ℃ for 1000 hours.
The above is only a specific application example of the present invention, and the protection scope of the present invention is not limited in any way. All the technical solutions formed by equivalent transformation or equivalent replacement fall within the protection scope of the present invention.
Claims (10)
1. A macromolecule resistance type humidity sensitive element is characterized by comprising a packaging shell, a base body, a humidity sensitive film, interdigital electrodes and pins, wherein the base body is a humidity sensitive sensing base body and is arranged in the packaging shell; the interdigital electrodes include transverse electrodes and longitudinal electrodes.
2. The polymer resistor type humidity sensor according to claim 1, wherein the substrate is ceramic, the interdigital electrode is made of conductive ink, a plurality of pairs of interdigital electrodes are screen-printed on the surface of the ceramic substrate, the leads are welded on the interdigital electrode, the humidity sensing film is made of a plurality of layers of humidity sensing materials, the humidity sensing materials are polyelectrolyte organic matters, and the thickness of the humidity sensing film is 30-34 microns.
3. A polymer resistance type humidity sensor according to claim 1, wherein the interdigital electrodes have a finger width of 0.2-0.25mm, a finger-to-finger spacing of 0.15-0.2mm, and a thickness of 10-15 μm.
4. The polymer resistance type humidity sensor according to claim 1, wherein the preparation method of the polymer resistance type humidity sensor comprises two parts of preparation of interdigital electrodes and preparation of a humidity-sensitive film;
polyelectrolyte organic matters of the humidity-sensitive film comprise poly (4-sodium styrene sulfonate), hydroxyethyl cellulose and polydiene dimethyl ammonium chloride solution;
firstly preparing an interdigital electrode, and then arranging a humidity-sensitive film on the surfaces of a substrate and the interdigital electrode to form a high-molecular composite humidity-sensitive film.
5. A polymer resistance type humidity sensor according to claim 1, wherein:
the preparation process of the interdigital electrode is as follows:
the first step is as follows: preparing the interdigital electrode by adopting a screen printing technology, and printing ink: the mass ratio of the copper powder is (8-10): 1, preparing the printing ink into paste;
the second step is that: then, injecting the paste onto a first screen printing plate with partial interdigital electrode patterns, wherein the patterns of the first screen printing plate correspond to the printing transverse electrodes, scraping the paste under the conditions of an inclination angle of 35-45 degrees and a pressure of 5-15 newtons, manufacturing the transverse electrodes and drying;
the third step: aligning the electrode dried after the second step of printing with a second silk screen plate with partial interdigital electrode patterns, wherein the patterns of the second silk screen plate correspond to the printed longitudinal electrodes, scraping paste under the same condition, printing the longitudinal electrodes and drying;
the fourth step: repeating the operations of the second step and the third step once in sequence;
the fifth step: and injecting paste of the silver-palladium alloy onto the silk screen with the shape of the pad to print the pad, and then drying.
6. A polymer resistance type humidity sensor according to claim 5, wherein: printing ink: the mass ratio of the copper powder is 9: 1, in a ratio of 1.
7. The polymer resistor type humidity sensor according to claim 4, wherein:
wherein, the preparation process of the humidity sensitive film is as follows:
the first step is as follows: mixing poly (4-sodium styrene sulfonate), deionized water and hydroxyethyl cellulose according to the weight ratio of (13-17): 100: (13-17) mixing according to the weight ratio, and fully stirring to completely dissolve the powdery material to obtain a first solution;
the second step is that: taking a proper amount of polydiene dimethyl ammonium chloride solution as a second solution;
the third step: uniformly coating the first solution on the surfaces of the substrate and the interdigital electrode by using a dispenser, standing at room temperature for 3-5 minutes, and uniformly coating the second solution after drying;
the fourth step: sintering and curing the humidity sensitive element in a muffle furnace to form a humidity sensitive film with the thickness of 30-34 microns on the surface, wherein the temperature rise program is as follows: the temperature is first reached to 90-110 ℃ from room temperature over 30-50 minutes and then maintained for 90 minutes.
8. The polymer resistor type humidity sensor according to claim 7, wherein:
the MW (molecular weight) of poly (4-sodium styrene sulfonate) is 70000, which is a powder material;
the hydroxyethyl cellulose has MW 90000;
the weight ratio of the poly (sodium 4-styrene sulfonate), the deionized water and the hydroxyethyl cellulose is preferably 17: 100: 13.
9. the polymer resistor type humidity sensor according to claim 7, wherein: polydiene dimethyl ammonium chloride solutions have two specifications:
the first specification is that the weight ratio of polydiene dimethyl ammonium chloride in water is 20%, MW is 400000-500000, and the viscosity at 25 ℃ is 800-1000 cP;
the first specification is polydienedimethylammonium chloride in water at a weight ratio of 35%, MW < 100000, viscosity at 25 ℃ of 100-200 cP.
10. A polymer resistance type humidity sensor according to claim 9, wherein: the polydiene dimethyl ammonium chloride solution is prepared by the weight ratio of polydiene dimethyl ammonium chloride in water being 20%, MW ═ 400000-.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011468762.6A CN112611787A (en) | 2020-12-15 | 2020-12-15 | High-molecular resistance type humidity sensitive element and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011468762.6A CN112611787A (en) | 2020-12-15 | 2020-12-15 | High-molecular resistance type humidity sensitive element and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112611787A true CN112611787A (en) | 2021-04-06 |
Family
ID=75233796
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011468762.6A Pending CN112611787A (en) | 2020-12-15 | 2020-12-15 | High-molecular resistance type humidity sensitive element and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112611787A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113203771A (en) * | 2021-04-27 | 2021-08-03 | 华中科技大学 | Humidity sensing fiber and preparation method and application thereof |
| CN114062443A (en) * | 2021-11-10 | 2022-02-18 | 北京印刷学院 | Flexible sensor for monitoring humidity of package headspace |
| CN117091653A (en) * | 2023-08-24 | 2023-11-21 | 哈尔滨理工大学 | Double-parameter thin film sensor for safety monitoring of energy storage system and preparation method and application thereof |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1384354A (en) * | 2002-05-24 | 2002-12-11 | 杨慕杰 | Compound polymer resistor type film humidity-sensitive element and its making process |
| CN2543063Y (en) * | 2002-05-24 | 2003-04-02 | 杨慕杰 | Composite high polymer resistance film humidity-sensitive element |
| JP2007280789A (en) * | 2006-04-07 | 2007-10-25 | Matsushita Electric Ind Co Ltd | Planar heating element |
| CN101077529A (en) * | 2007-07-05 | 2007-11-28 | 中南大学 | Method for preparing nano copper powder and copper slurry |
| US20080004358A1 (en) * | 2004-12-22 | 2008-01-03 | Mitsui Mining & Smelting Co., Ltd. | Superfine Copper Powder Slurry and Production Method Thereof |
| CN102323300A (en) * | 2011-07-18 | 2012-01-18 | 浙江大学 | Polyelectrolyte and graphene composite resistive moisture sensor and manufacturing method thereof |
| CN102854222A (en) * | 2012-09-27 | 2013-01-02 | 吉林大学 | Moisture-sensitive sensor based on potassium tantalite sensitive membrane and preparation method thereof |
| CN102928474A (en) * | 2012-11-28 | 2013-02-13 | 吉林大学 | Moisture-sensitive sensor based on titanium-containing organic framework material and preparation method thereof |
| CN103149246A (en) * | 2012-09-27 | 2013-06-12 | 中国石油大学(华东) | Graphene film humidity sensor |
| CN104677767A (en) * | 2015-03-04 | 2015-06-03 | 浙江大学 | QCM (quartz crystal microbalance) based polypyrrole/ titanium dioxide frequency type film gas sensitive sensor and preparation method thereof |
| CN107337965A (en) * | 2017-08-28 | 2017-11-10 | 厦门大学 | A kind of preparation method of anti-oxidant copper system electrically conductive ink |
| CN107577381A (en) * | 2017-07-31 | 2018-01-12 | 珠海纳金科技有限公司 | A kind of volume to volume capacitive touch screen functional sheet and preparation method thereof |
| US20190140124A1 (en) * | 2016-06-30 | 2019-05-09 | Byd Company Limited | Photovoltaic cell assembly, photovoltaic cell array, and solar cell assembly |
| CN213957215U (en) * | 2020-12-15 | 2021-08-13 | 无锡豪帮高科股份有限公司 | High-molecular resistance type humidity sensitive element |
-
2020
- 2020-12-15 CN CN202011468762.6A patent/CN112611787A/en active Pending
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1384354A (en) * | 2002-05-24 | 2002-12-11 | 杨慕杰 | Compound polymer resistor type film humidity-sensitive element and its making process |
| CN2543063Y (en) * | 2002-05-24 | 2003-04-02 | 杨慕杰 | Composite high polymer resistance film humidity-sensitive element |
| US20080004358A1 (en) * | 2004-12-22 | 2008-01-03 | Mitsui Mining & Smelting Co., Ltd. | Superfine Copper Powder Slurry and Production Method Thereof |
| JP2007280789A (en) * | 2006-04-07 | 2007-10-25 | Matsushita Electric Ind Co Ltd | Planar heating element |
| CN101077529A (en) * | 2007-07-05 | 2007-11-28 | 中南大学 | Method for preparing nano copper powder and copper slurry |
| CN102323300A (en) * | 2011-07-18 | 2012-01-18 | 浙江大学 | Polyelectrolyte and graphene composite resistive moisture sensor and manufacturing method thereof |
| CN102854222A (en) * | 2012-09-27 | 2013-01-02 | 吉林大学 | Moisture-sensitive sensor based on potassium tantalite sensitive membrane and preparation method thereof |
| CN103149246A (en) * | 2012-09-27 | 2013-06-12 | 中国石油大学(华东) | Graphene film humidity sensor |
| CN102928474A (en) * | 2012-11-28 | 2013-02-13 | 吉林大学 | Moisture-sensitive sensor based on titanium-containing organic framework material and preparation method thereof |
| CN104677767A (en) * | 2015-03-04 | 2015-06-03 | 浙江大学 | QCM (quartz crystal microbalance) based polypyrrole/ titanium dioxide frequency type film gas sensitive sensor and preparation method thereof |
| US20190140124A1 (en) * | 2016-06-30 | 2019-05-09 | Byd Company Limited | Photovoltaic cell assembly, photovoltaic cell array, and solar cell assembly |
| CN107577381A (en) * | 2017-07-31 | 2018-01-12 | 珠海纳金科技有限公司 | A kind of volume to volume capacitive touch screen functional sheet and preparation method thereof |
| CN107337965A (en) * | 2017-08-28 | 2017-11-10 | 厦门大学 | A kind of preparation method of anti-oxidant copper system electrically conductive ink |
| CN213957215U (en) * | 2020-12-15 | 2021-08-13 | 无锡豪帮高科股份有限公司 | High-molecular resistance type humidity sensitive element |
Non-Patent Citations (1)
| Title |
|---|
| 李秋顺 等: "涂覆PDDA/PSS膜的长周期光栅对湿度的响应性能", 《山东科学》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113203771A (en) * | 2021-04-27 | 2021-08-03 | 华中科技大学 | Humidity sensing fiber and preparation method and application thereof |
| CN113203771B (en) * | 2021-04-27 | 2022-08-05 | 华中科技大学 | Humidity sensing fiber and preparation method and application thereof |
| CN114062443A (en) * | 2021-11-10 | 2022-02-18 | 北京印刷学院 | Flexible sensor for monitoring humidity of package headspace |
| CN114062443B (en) * | 2021-11-10 | 2023-10-03 | 北京印刷学院 | Flexible sensor for monitoring humidity of package headspace |
| CN117091653A (en) * | 2023-08-24 | 2023-11-21 | 哈尔滨理工大学 | Double-parameter thin film sensor for safety monitoring of energy storage system and preparation method and application thereof |
| CN117091653B (en) * | 2023-08-24 | 2024-04-12 | 哈尔滨理工大学 | Double-parameter thin film sensor for safety monitoring of energy storage system and preparation method and application thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112611787A (en) | High-molecular resistance type humidity sensitive element and preparation method thereof | |
| CN100523799C (en) | Polyelectrolyte / intrinsic conducting polymer composite humidity sensor and its production method | |
| McGovern et al. | Micro-humidity sensors based on a processable polyaniline blend | |
| Su et al. | Humidity sensors based on TiO2 nanoparticles/polypyrrole composite thin films | |
| CN100549686C (en) | A kind of vapor sensor and be used for the material of this sensor | |
| Vaghela et al. | Biopolymer-polyaniline composite for a wide range ammonia gas sensor | |
| JPH05500568A (en) | capacitance humidity sensor | |
| EP0076131A1 (en) | Humidity sensor and method for preparing a humidity sensor | |
| CN213957215U (en) | High-molecular resistance type humidity sensitive element | |
| CN103233256B (en) | A kind of PEDOT/bmim[PF6] preparation method of conductive ion liquid polymers air-sensitive film sensor | |
| US20030107385A1 (en) | Polymer-type humidity sensor | |
| Li et al. | A novel highly reversible humidity sensor based on poly (2-propyn-2-furoate) | |
| JP2011027458A (en) | Humidity sensor | |
| CN201340404Y (en) | Macromolecule composite resistive-type humidity sensitive element with nanofiber structure | |
| JPS6156952A (en) | Moisture sensitive resistor element | |
| JPS60168044A (en) | Moisture sensitive material | |
| CN110632126A (en) | Organophosphorus compound sensor and preparation method thereof | |
| US20070139155A1 (en) | Humidity sensor and method for making the same | |
| CN106596655A (en) | Resistive-type humidity sensitive sensing element and preparation method thereof | |
| CN201016949Y (en) | Macromolecular resistance type thin film humidity element with strong water resistance | |
| CN201096743Y (en) | Focused electrolyte/feature conductive polymer compound resistance film humidity sensitive part | |
| Chen et al. | A fast response resistive thin film humidity sensor based on poly (4‐vinylpyridine) and poly (glycidyl methacrylate) | |
| Martadi et al. | Design and fabrication of PVA-based relative humidity sensors using thick film technology | |
| CN100451634C (en) | Dew sensor and manufacturing method thereof | |
| CN208937525U (en) | A kind of thin-film capacitor humidity sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210406 |
|
| RJ01 | Rejection of invention patent application after publication |