JPH02193045A - Chemical material sensor - Google Patents

Abstract

PURPOSE:To enable measurement of a thickness of a sensor film by forming the sensor film containing a compound sensitive to a chemical material on a base body through a pigment film to enable the control of the thickness of the sensor film. CONSTITUTION:A sensor film 12 containing a compound sensitive to a chemical material is formed on a transparent base body 11 through a pigment film 13. A light emitting element 21 and a light receiving element 22 are arranged on the back side of the base body 11 and housed integral in a casing 30. Therefore, light emitted from the light emitting element 21 is made incident from the back side of the base body 11 and the current mirror reflection factor of the light is captured with a light receiving element 22 provided also on the back side of the base body 11 to detect and determine a chemical material to be inspected from a change in the reflection factor. In this manner, a thickness of the sensor film 12 can be controlled to bring the sensor film into contact with a fluid to be inspected containing the chemical material to be inspected thereby enabling measurement of the chemical material to be inspected according to the thickness of the film.

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a chemical substance sensor capable of detecting and quantifying chemical substances. <Conventional technology> It selectively adsorbs or selectively reacts with specific chemical substances existing in the outside world, and the type and concentration of the chemical substance can be determined from the resulting changes in electrical signals such as resistivity and dielectric constant. Chemical sensors for detection are known. Such chemical sensor materials include semiconductors, ceramics, polymers, etc., and are actually applied to the detection and quantification of water vapor, various gases, various ions, etc. Sensors using cholesteric liquid crystals are also known.

[JP-A-53-76094, JP-A-58-426
No. 85, Tsukahara, Mechatronics special issue, Dan-L]
103 (1981), Sensor Technology, LLLL, 62
(1987) ``-1''-, 97 (1987)
, 7(12). 87 (19B?)]. This device utilizes the color change of liquid crystal. On the other hand, with the recent development of office automation equipment, etc., there is a demand for various sensors that can operate stably and accurately even in environments with strong electric fields such as copying machines, so sensors that use optical detection and quantitative methods are advantageous. It is. Among these, optical methods utilize the change in the amount of light absorption or fluorescence (fluorescence quenching) caused by the reaction of certain dyes or compounds with gas substances or the formation of charge transfer complexes. Detection and quantitative methods are known. For example, those utilizing the discoloration caused by the reaction of N,N-dimethylaniline with 02 (Japanese Unexamined Patent Publication No. 100337/1982), poly-2-bala(methacroylaminophenyl)-5-
A method that utilizes discoloration caused by the reaction of phenyl-1,3-oxazole with NHs or amines (Japanese Patent Laid-Open No. 60-202
334), tris(4,7-diphenyl-1,10-
There is a method (Japanese Unexamined Patent Publication No. 178646/1983) that utilizes the change in fluorescence caused by the reaction between Ru complex (phenanthroline) and O3. Furthermore, a method utilizing absorption change in bromothymol blue film due to NH (Nikkei Sangyo Shimbun, December 1988)
(Published on the 14th of May), NO. [Chemical Society of Japan Spring Annual Meeting Proceedings 3nHO7 (1988), Nikkei Sangyo Shimbun, published June 10, 1988] etc. can also be mentioned. Although there are few examples of devices that utilize light reflection, devices that use metal films or metal salts are being considered. For example, one that utilizes the reaction between palladium potassium sulfite and CO (Japanese Patent Laid-Open No. 58-79141), and one that utilizes the reaction between HgBra and AsHs (Japanese Patent Laid-Open No. 60-4264).
No. 5), which utilizes the corrosion of metal films by SF (Japanese Patent Application Laid-open No. 8066/1983). Furthermore, as a humidity sensor, an optical fiber or one that uses a change in refractive index by providing a hygroscopic material as a cladding on an optical fiber (JP-A-61-217744, JP-A-6
2-9255, JP-A No. 62-204143, etc.), those using inorganic compounds that change color due to moisture absorption (JP-A-54-80190, JP-A-61-139478)
, those that utilize changes in absorption coefficient, changes in scattering intensity, or color development due to hygroscopic resin etc. (Japanese Patent Laid-Open No. 56-67738)
No., JP-A-56-110039, JP-A-58-216
No. 936), and furthermore, one that utilizes changes in diffused reflection using a transparent body with unevenness and a moisture absorbent (Japanese Unexamined Patent Publication No. 59-1999)
204742), or one that utilizes reflected light and transmitted light from a mirror consisting of two types of dielectric layers having different refractive indexes (Japanese Patent Laid-Open No. 62-39744). However, there are no proposals that utilize the reflection of a pigmented film. <Problems to be Solved by the Invention> Sensors using semiconductors, ceramics, polymers, etc. as described above generally have a drawback that the film is thick and the response is slow due to the diffusion process of the gas to be detected. Also, there are many things that need refreshing. Furthermore, changes in resistance values are often detected, and since this is done by electrical means, it is easily affected by strong electric fields and changes over time. In addition, many of the device manufacturing methods involve complicated processes (
Many of the detection circuits and the like are also complicated. On the other hand, sensors using cholesteric liquid crystals utilize color changes due to changes in pitch, so the wavelength distribution of light reflection changes diversely and is not constant, has low sensitivity, and is highly temperature dependent. , etc. have drawbacks. In addition, when using changes in absorption or fluorescence using dyes, dyes, etc. that can selectively bind or react with the gaseous substance or other analyte to be detected or quantified (the disadvantage of being limited to When manufacturing such devices, it is necessary to highly orient the dye molecules when applying the LB film, such as the one that utilizes the fluorescence change in the LB film, or the use of a bromothymol blue film. In many cases, advanced or complicated processes are required, such as those that utilize the absorption change in metals, such as the provision of a metal reflective film.Furthermore, those that use metal films or metal salts All reactions are irreversible, and even these reactions have the disadvantage that the combinations of sensor materials and test substances such as gaseous substances are limited. In order to do this, the film is characterized in that it contains a dye and a chemical substance-sensitive compound, and the light reflectance of the film changes when the chemical substance-sensitive compound binds to the test chemical substance. Chemical substance sensor.” (Patent application 1986-2194)
No. 34) and ``a substrate, a sensor film formed on the substrate, a light-emitting element, and a light-receiving element, the sensor film contains a dye and a chemical substance-sensitive compound, and the chemical substance-sensitive compound is coated. The film is configured so that the light reflectance of the film changes when combined with a test chemical substance, and the change in light reflectance is detected by the light receiving element to detect and quantify the test chemical substance. "Chemical substance sensor" (Japanese Patent Application No. 63-219921) has been proposed. However, in this method, it is necessary to form the chemical substance-sensitive compound and the dye in the same film, which requires compatibility between them, which limits the number of test chemicals that can be tested. There is. Further, due to this, the content of the dye is limited, resulting in a problem that sufficient detection sensitivity cannot be obtained. The present invention has a wide range of selection of test chemical substances, and the detection and
It is an object of the present invention to provide a chemical substance sensor that has high precision in quantitative determination, quick response, easy element configuration, excellent durability, and is advantageous in terms of cost. Means for Solving the Problems> In order to achieve the above objects, the chemical substance sensor of the present invention has a substrate, a sensor film laminated with a dye film on the substrate, and the sensor film has chemical substance sensitivity. The dye film contains a chemical compound, and is configured so that the light reflectance of the dye film changes when the chemical substance-sensitive compound binds to the test chemical substance. In the above, the sensor film is preferably laminated on the substrate via the dye film, and further includes a light emitting element and a light receiving element, and changes in light reflectance through the substrate of the dye film are detected by the light receiving element. Detects the test chemical substance by detecting the element,
Preferably, it is configured to quantify. Light reflection by the dye film is due to multiple reflections within the film, and is strongly influenced by the dye-sensor film interface. For this reason, when the compound in the sensor film combines with the test chemical substance, the refractive index, film thickness, etc. change, and the pigment film reflectance increases (changes). The sensor film of the present invention is undesirable because the multi-reflection effect is small. As a multi-reflection film, not only a dye film but also a laminated dielectric film can be used. This chemical-sensitive compound changes the physical properties of the film by combining with the test chemical, and this change in film properties changes the light reflectance, especially the specular reflectance, of the dye film laminated on the sensor film. Specific Structure> The structure of the present invention will be described in detail below. In the present invention, the sensor film is formed on the substrate in a laminated state with the dye film. Thus, in the present invention Since the sensor film and the dye film are separately laminated, patent application No. 63-2194
34 and No. 63-219921, in which a chemically sensitive compound and a dye are contained in the same film, there is no consideration of compatibility between the chemically sensitive compound and the dye. Therefore, the content of the dye in the dye film can be increased, the reflectance change of the dye film becomes sufficient, and sufficient sensitivity can be obtained. Furthermore, desired sensitivity can be obtained by controlling the thickness of the dye film. In the present invention, the sensor film is laminated with the dye film, but it is preferable that the sensor film is formed on the substrate via the dye film. By forming in this way, detection can be performed from the back side of the substrate. The pigmented film of the present invention has a specular reflectance of 10% or more, more preferably 20% or more, when measured at an angle of 20° or less, especially 5°, particularly at any wavelength in the visible to infrared region. , it is preferable to have so-called bronze luster. Further, the absorption rate of the dye film in the present invention is preferably 70% or less, preferably 50% or less, and the maximum wavelength of reflection (λRma y) in the pigment film is the maximum wavelength of absorption (λ
A , , , ) is preferably different from R1 □ - λA, 1 . It is desirable that the thickness is ≧50 nm. By using such a dye film, substantially sufficient sensitivity can be obtained. This is because when the reflectance is less than 10%, it becomes difficult to detect the test chemical substance as a change in reflectance. By measuring the reflectance by specular reflection of 20° or less, sensitivity is increased and the device can be made more compact. What are the pigments that make up such a pigment film? There is no particular restriction as long as the reflectance is 10% or more, but
Specific examples include cyanine dyes, azulenium dyes, biryllium dyes, squarylium dyes, croconium dyes, quinone/naphthoquinone dyes, metal complex dyes, phthalocyanine dyes, and naphthalocyanine dyes. In addition, when using polymethine dyes such as cyanine dyes, -doublet oxygen quenchers may be mixed and used,
The quencher in this case is a metal complex, especially Ni
Complexes such as dithiol-based (particularly bisphenyldithiol-based) Ni complexes and amine compounds are preferred. Further, an ionic combination of a quencher anion and a cyanine dye cation may be used. The chemical substance sensitive compound contained in the sensor membrane in the present invention is a compound that binds to a specific chemical substance reversibly or irreversibly, and may be selected depending on the test chemical substance. More specifically, chemically sensitive compounds have various bonding states between their molecules and the target chemical substance to be tested, and these bonds include various reactions, covalent bonds, ionic bonds, etc. In addition to various bonds such as , coordinate bonds, adsorption, absorption, etc. are included. The binding and desorption between the chemical substance-sensitive compound and the test chemical substance is preferably reversible, but may be irreversible. When the chemical substance to be tested is water, a hydrophilic compound is used as the chemically sensitive compound. For hydrophilic compounds, solubility parameters (solubi
ity parao+eter SP value δ=(CH
D) "2CHD, cohesive energy density cohesiv
energy density) is 17 (MJ/m
")""or more, especially 17-40 (MJ/m")""
Yo') Good * L < Ha18~40 (MJ/m")
”” Sarah 4. : Preferably 20 to 30 (MJ/a+
")" is preferable. The solubility parameter is calculated according to the following or calculated from the actual value. A. Calculated from the heat of evaporation δ= (E v / y) l/I Ev: molar evaporation energy ( J/mol), ■: Calculated from molar volume (literally "/mol). However, in the case of polymers, they do not vaporize, so follow B and C below. B. Actual measurement from compatibility (1) Swelling degree In particular, cross-linked three-dimensional polymers are insoluble in solvents, so observe the degree of swelling and determine the s of the solvent with the greatest swelling effect.
Let the p value be the sp value of the polymer (D, Mangaraj,
MacroIlol, cheII+,, 65.2
9 (1963)). (2) Viscosity: In a solvent with good compatibility, the polymer chain is spread out, so the viscosity is high. Measure the intrinsic viscosity η in various solvents and plot it against the sp value of the solvent used. The sp value showing the maximum is taken as the sp value of the polymer (D, Mangaraj
, S., Patra and S., B., Rath, Ma.
klomol, cheIl, 67.84 (196
3). 65.39 (1963), G. M. Bistow an
d W, F. Watson. Trans, Faraday, Soc, 54.1
742 (19581). (3) Turbid point titration method: A tributary solvent of the polymer is dropped into a polymer solution, and the s
Determine the p-value (K, W, 5uhand D, H,
C1arke, J., Polym, Sci., 5.1
671 (1967), K.W., Suh and J.
M, Corbett, J, Apl)l. Polyn+, Sci, 12.2359 (1968
)). Calculation from C8 chemical structure Small's method (P, Small, J, Appl,
Chem., 3°71 (1953)), preferably the method of Fedors (R.F. Fedors, Pol.
ym, Eng, Sci, 14147 (1974)
), it can be calculated from the evaporation energy Δei and molar volume Δvi of atoms and atomic groups. In the present invention, one or more of the above hydrophilic compounds A,
The sp value calculated from either B or C is 17 (MJ
/s")"" or more. Also, when one or more of the hydrophilic compounds used is formed as a single layer film, the contact angle with water is 701 or less, especially lO~70 It is preferable to A hydrophilic polymer compound having a polar group is preferable in order to have a contact angle of In addition, there are polymer compounds containing cyano groups, halogens, etc., including the following: a) Water-absorbing polymer anion salts (particularly salts that absorb water reversibly) For example, sodium alginate, polyacrylic b) Polyelectrolytes such as polyethyleneimine hydrochloride, polyethyleneimine/polystyrene. Sulfonic acid, polyN-methylpyridinium chloride, etc. C) Thermosetting resin phenolic resin, furan resin, alkyd resin, epoxy resin, melamine resin, unsaturated polyester resin, etc. d) Thermoplastic resin polyvinyl acetate, polyacrylate, Polymethacrylate, polyvinyl chloride, polyacrylonitrile, polyvinyl alcohol, polyether, polyamide, polyester, polyurethane, polyvinyl ketone, polyvinylidene chloride, polyvinylpyrrolidone (PVP), polyalkylene (ethylene) glycol, polyacrylamide, PV
A-ethylene copolymer, etc. e) Cellulose-based acetylcellulose, triacetylcellulose, nitrocellulose, acetylbutylcellulose, propionylcellulose, ethylcellulose, carboxymethylcellulose, etc. f) Natural polymers and their derivatives casein, amylose, polyglycine, modified starch (
grafted starch) etc. g) These blends or copolymers may be crosslinked to have a three-dimensional structure. These polymer compounds are preferably used because they have good film properties and high water resistance. II, hydrophilic low-molecular organic compound h) Water-absorbing organic metal salt (especially a salt that absorbs water reversibly) For example, sodium acetate, sodium potassium tartrate,
such as sodium lactate. III. Hydrophilic inorganic compounds i) Water-absorbing inorganic metal salts (especially salts that absorb water reversibly) such as Li C12t, Ca C2m, COC (
metal halides such as lz, etc. j) Hydrophilic gels, such as colloidal silica or silicates such as silicon alkoxides, hydrolysates of titanates, aluminates, zirconates, etc. One or more of these compounds may be used. At this time, it can be used as a humidity sensor that detects water vapor. Next, when using ammonia as the test chemical substance, bromothymol blue, thymol blue, acridine orange, poly-2-para(methacroylaminophenyl)-
5-7 enyl-1,3-oxazole or the like may be used as the chemical substance sensitive compound. Furthermore, crown ether is used when the test chemical substance is an alkali metal or alkaline earth metal ion such as Na"K" or various metal ion such as Ag". As a crown ether, benzo-15-crown 5 is used.
(Test chemical substance HNa”), dibenzoviridino 18-
Crown-6 (test chemical substance; various metal ions), Cryptofix 222CC (manufactured by Merck) (test chemical substance; , etc.) can be used.In addition, cholesteric liquid crystal can be used for various gases, pyrene,
N,N-dimethylaniline, tris(4,7-diphenyl-1,10-phenanthroline) Ru complex, (CβC
H2CHI)ts or (CI2CHz CHi)a
Triphenylmethine neutral red and the like are examples of substances using NH as the test chemical substance. In the present invention, as described above, the chemical substance sensitive compound and the test chemical substance combine with each other in the sensor film, thereby changing the light reflectance of the dye film laminated on the sensor film. Detecting chemical substances. The change in light reflectance in this case is considered to be due to changes in film properties such as film thickness, film density, and refractive index, as described above. That is, in the present invention, changes in film physical properties in response to the bond between a chemical substance-sensitive compound and a test chemical substance are detected by changes in the light reflectance of a dye film that exhibits high specular reflectance, and the test chemical substance is quantified. It is something. More specifically, it is thought that in hydrophilic compounds such as hydrophilic polymer water-absorbing salts and hydrophilic gels, hydration occurs due to water vapor, and water is adsorbed or absorbed. In addition, it is thought that this is due to some kind of interaction between bromothymol blue and ammonia, and ultimately the formation of a charge transfer complex. In the case of crown ethers, this is thought to be due to inclusion of ions such as alkali metals and alkaline earth metals. The above bond may be reversible or irreversible as long as it changes the light reflectance of the film. However, from the point of view of repeated use of the sensor, it is preferable that the sensor be reversible. Although it is possible to use only the change in light reflectance as described above,
In some cases, light transmittance can also be used.
Furthermore, in addition to changes in reflectance and transmittance with monochromatic light, it is possible to provide a range of measurement wavelengths and detect changes in the amount of reflected light or transmitted light. In this case, an LED can be used as a light source, and it is preferable because the amount of light varies widely. In such a case, as described above, it is preferable to use specular reflection. or may contain a binder such as a self-oxidizing resin such as nitrocellulose, or a thermoplastic resin such as polystyrene or nylon.In this case, the content of the pigment is 60%.
The content is preferably 90 to 100 wt%, preferably 90 to 100 wt%. With such a content, changes in the physical properties of the film can be sufficiently reflected in the light reflectance of the dye film. Further, the thickness of the dye film may be selected depending on the desired sensitivity, etc., and is approximately 400 to 200 OA. The sensor film in the present invention may be formed only from chemical substance-sensitive compounds (this is a preferred embodiment). In the examples, especially when using a hydrophilic polymer compound, a coating film with good film properties can be obtained.In addition, when ammonia is used as the test chemical substance, poly-2-para(methacroylaminophenyl)- The same applies to 5-phenyl-1,3-oxazole, etc. For other compounds, films may be formed by coating or vapor deposition. Also, a sensor film can be created by using a combination of similar chemically sensitive compounds. In this case, for example, a polymer compound sensitive to chemical substances may have a binder function.Furthermore, binders such as various polymers that do not inhibit the function as a chemical substance sensitive compound may be used in combination. The content of the chemical substance sensitive compound in the above may be 50 to 10.
The content is preferably 0wt%, preferably 80 to loOwt%. With such a content, the physical properties of the sensor film can be sufficiently changed. In addition, the sensor film in this case is 0.05 to 1007171
, preferably 0.1 to 5-. In this way, it becomes possible to form a thin film, and the response as a sensor becomes faster. Although the material of the substrate in the present invention is not particularly limited, it is preferably substantially transparent, since detection can be performed from the back side of the substrate. Specifically, glass, hard vinyl chloride, polyethylene terephthalate (PET), polyolefin, polymethyl methacrylate (PMMA), acrylic resin, epoxy resin, polycarbonate resin, polysulfone resin, polyethersulfone, methylpentene polymer, bisphenol A- Examples include various resins such as terephthalic acid copolymers. The shape of such a substrate is not particularly limited, but it is usually plate-like or film-like. In order to manufacture the chemical substance sensor of the present invention, a dye film may be formed on a substrate, and a sensor film may be layered thereon. The dye film and the sensor film may be formed by preparing a dye coating solution and a chemical substance-sensitive compound coating solution, respectively, and forming the coating films. Application during coating film formation may be performed by spin cord, dipping, spraying, or the like. The solvent used in preparing the coating solution is not particularly limited as long as the dye or chemically sensitive compound is soluble therein. Specifically, keto alcohols (aliphatic keto alcohols, especially diacetone alcohol, acetol, acetoin, acetoethyl alcohol, etc.), R, O-R, -OH[
Here, R1 is a lower alkyl group (particularly having 1 to 5 carbon atoms)
, R2 represents a lower alkylene group (particularly having 2 to 5 carbon atoms), ether type represented by ], ketone type such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, butyl acetate, ethyl acetate, carpitol acetate, Ester systems such as butylcarpitol acetate,
Examples include ether type citoluene such as methyl cellosolve and ethyl cellosolve, aromatic type such as xylene, halogenated alkyl type such as dichloroethane, water, and alcohol. Under these circumstances, when using a water-absorbing polymeric anion salt that becomes a double sensor (for chemical substance-sensitive compounds), a sensor membrane can be produced by the following method. That is, the chemical substance sensitive compound has an anionic group,
In the case of a soluble salt having a positive counter ion such as Na, NH, etc. that pairs with this anion group, after forming a coating film as described above, the positive counter ion is exchanged with the salt and at the same time the metal It is possible to introduce a halide into the film. By making such a soluble salt insoluble through salt exchange, the stability of the coating film is improved, such as being extremely stable against moisture of the test chemical substance. Further, by leaving an excess amount of metal halide such as CaCl2 in the coating film, the function as a sensor film can be improved. Therefore, it is necessary that metal halides such as CaCl2□ exist in this form in the coating film, and it is necessary to use it by immersing it in a salt exchange solution and drying it as is, or after exchanging it, washing it with water or a purified solvent, and then using it again. It may be immersed in another salt solution having the same composition as the salt exchange solution. The solution of CaCβ3 etc. used for salt exchange has a content of 1 to 10 wt%,
Preferably it is 2 to 5 wt%. As the solvent used for the salt exchange solution, the same ones as the coating solvent can be mentioned. However, it is necessary that the polymeric anion salt and the substrate obtained by salt exchange are hardly soluble and can dissolve the salt of the counter ion to be subjected to salt exchange. Salt exchange may be performed at a temperature of 0 to 60°C for about 1 to 60 minutes. The film thickness in this case is 0.05 to 0.14, but Ca
It can be selected as appropriate depending on the amount of C42a, etc. In the present invention, the dye film and sensor film may be formed by vapor deposition. That is, it may be carried out according to a known method using a dye or a chemical substance-sensitive compound as a vapor deposition source. Examples of dyes that can be applied at this time include phthalocyanine dyes, naphthalocyanine dyes, squarylium dyes, and croconium dyes. In the present invention, the membrane surface of the sensor membrane may be further air-sandched with a breathable protection plate, or a breathable protection plate may be provided on the membrane surface. Further, a filter through which a specific chemical substance can pass may be provided on the membrane surface. In the present invention, after forming a dye film and a sensor film on a substrate,
This may be punched or cut into desired dimensions. This method is preferable in terms of mass productivity. Alternatively, a glass fiber may be used as the substrate, and a dye film and a sensor film may be formed on the end face thereof. Furthermore, a plurality of these materials may be bundled and used. Alternatively, the materials may be bundled and the end surfaces polished, and a dye film and a sensor film may be formed on the end surfaces. In the chemical substance sensor of the present invention, it is possible to control the thickness of the sensor membrane, and by bringing it into contact with a test fluid containing a test chemical, the test chemical can be mixed in parts per billion (ppb) according to the film thickness.
It becomes possible to measure in the range of -100%. A preferred embodiment of the chemical substance sensor of the present invention includes, for example, the structure shown in FIG. In this device, a sensor film 12 containing a chemical substance-sensitive compound is formed on a transparent substrate 11 via a dye film 13, while a light emitting element 21 and a light receiving element are arranged on the back side of the transparent substrate 11. 22 are installed, and these items are housed integrally within the casing 30. Therefore, the light emitted from the light emitting element 21 is incident on the back surface of the base 11, and the specular reflectance of the light at this time is captured by the light receiving element 22, which is also provided on the back surface of the base 11, and from the change in reflectance, the test chemical is detected. Detection and quantification. In this case, it is preferable to install the light-emitting element 21 and the light-receiving element 22 close to each other, and by measuring reflection by specular reflection of 20' or less, especially 5 degrees or less, sensitivity is increased and the element can be made more compact. can be measured. The wavelength of the light emitted by the light emitting element 21 in the present invention is in the visible to infrared range. The light emitting element 21 is not particularly limited, but is preferably a light emitting diode (LED), a laser diode (LD), or the like. Further, the light receiving element 22 is not particularly limited, but is preferably a photodiode, a phototransistor, or the like. In addition, the chemical substance sensor of the present invention is not particularly limited in its structure as long as the sensor film and the dye film are laminated (various embodiments are possible). This will be explained specifically by way of an example.Example 1 This 2 wt% methanol solution was coated on a glass plate (50 x 50 x 1 nuI+) as a dye, and 0.0
A dye film with a thickness of 8 μm was formed. After drying this, sodium alginate (SP value 20 (
Mu/m31" or more, contact angle 70' or less),
This 1 wt% aqueous solution was applied to form a coating film with a thickness of 0.06 μm. Then, 2 wt% CaCl2. The salt was exchanged by immersing it in an aqueous solution for 1 minute. After pulling it up, it was directly dried on a spinner. Furthermore, it was dried in a dryer (70°C, 1 hour).
,, As a result, the Ca salt of alginic acid and CaCl2
A sensor film containing , was formed. A sensor having the configuration shown in FIG. 1 was assembled using a glass substrate on which a sensor film was formed via the dye film described above. Note that the light emitting element has an L that emits light with a wavelength of 950 nm.
A PIN diode was used as a light receiving element for the ED. When the sensor thus produced was used for humidity measurement, it was possible to measure water vapor up to a concentration of 30 to 90% RH. An example of the relationship between the relative humidity and the output voltage of the sensor in this case is shown in FIG. This result shows that the measurement concentration range is wide and the linearity is also good. Example 2 Transparent PET (manufactured by Teijin, 0.2 mm thickness) was used as the substrate, and naphthalocyanine dye with the following structure (R”-5i (CHs) i-0-1-CH, C1,0+) was used as the dye.
, C4H,), a sensor film was formed in the same manner as in Example 1, and the sensor was assembled.
An almost linear output change was obtained. Example 3 Glass plate as the substrate, cyanine/with the following structure as the pigment
A sensor film was formed and a sensor was produced in the same manner as in Example 1 using a Ni complex salt. A nearly linear output change was obtained from 30 to 90% RH. Example 4 Transparent PET as the substrate, Phthalocyanine dye with the following structure as the dye, Sodium poly(4-styrenesulfonate) C3P value 2 as the chemical sensitive compound
A sensor film was formed in the same manner as in Example 1 using a contact angle of 0 (MJ/m')"" or more and a contact angle of 70 degrees or less), and a sensor was assembled. A substantially linear relationship was obtained in the same range from 30% to 90% RH. Example 5 This 2 wt% methanol solution was applied to a glass substrate (5
0x50x1 mm) to form a 0.088 μ thick dye film. After drying, it was placed in a 5 wt% Ca CI2z aqueous solution for 40 seconds for salt exchange. After drying, acetylcellulose (SP value 23 (MJ/m3) contact angle 70) was used as a hydrophilic compound for moisture-sensitive materials.
This 2 wt % cyclohexanone solution was applied to form a coating film with a thickness of 0.1 μm. When the sensor fabricated in this way was used to measure humidity,
As shown in FIG. 3, a substantially linear output change was obtained between 10 and 90% RH. Example 6 Ethyl cellulose (SP value 21 (MJ
A sensor was fabricated in the same manner as in Example 5 above, except that a contact angle of 70 @ or less) was used, and a nearly linear output change was similarly obtained at 10 to 90% RH. Example 7 As a moisture-sensitive material, triacetyl cellulose has a CSP value of about 2
A sensor was fabricated in the same manner as in Example 5, except that 0 (MJ/m'') ''・contact angle of 70'' or less) was used, and a nearly linear output change was similarly observed from lO to 90%RH. Obtained. <Effects of the Invention> The chemical substance sensor of the present invention is used to detect and quantify chemical substances in a test fluid. In this case, a sensor film containing a chemically sensitive compound that binds to the test chemical substance and a dye film containing a dye to detect changes in the film properties of this sensor film as changes in light reflectance are separately laminated. Therefore, there is no consideration of compatibility between chemical substance-sensitive compounds and dyes. Therefore, a uniform thin film can be obtained, the response as a sensor is fast, and the reflectance can be kept high, resulting in high accuracy. In addition, the selection range of test chemical substances is wide (in addition, it is possible to measure from the back side of the substrate, the measurable concentration range is wide (and the linearity is also good), and the element configuration is simple and compact. It is possible and easy to manufacture. In other words, there is no need for processes such as sintering and molding, and there is no need for electrodes, which is advantageous in terms of cost. In addition, it is advantageous in terms of cost. Since there is no electrical effect such as electrical interference, there is little deterioration and it can withstand continuous use.Furthermore, since there is no contact between the chemical substance to be tested and signal detection elements such as light-emitting elements and light-receiving elements, durability is also improved from this point of view. Good.

[Brief explanation of the drawing]

FIG. 1 is a cut end view showing a preferred embodiment of the chemical substance sensor of the present invention. FIGS. 2 and 3 are graphs showing the relationship between relative humidity and output voltage when the chemical substance sensor of the present invention is applied to a temperature sensor. FIG. 1 Explanation of symbols 11...Substrate 12...Sensor film 13...Dye film 21...Light emitting element 22...Light receiving element 30...Casing Applicant: Representative of TDC Co., Ltd. People Patent Attorney Ishii Kankan Patent Attorney
Increase 1) Tatsuya G, 2? F eye ``f E'X$ / ``hAgo H■ G. 5゜Relative humidity/% +00

Claims (3)

[Claims] (1) having a substrate and a sensor film laminated with a dye film on the substrate, the sensor film containing a chemical substance sensitive compound;
A chemical substance sensor characterized in that the chemical substance sensitive compound is configured to change the light reflectance of the dye film by binding with a test chemical substance. (2) The chemical substance sensor according to claim 1, wherein the sensor film is laminated on the substrate via the dye film. (3) A claim further comprising a light-emitting element and a light-receiving element, the light-receiving element detecting a change in light reflectance through the base of the pigment film, and detecting and quantifying the chemical substance to be tested. 2. The chemical substance sensor according to 1 or 2.