JP2007327899A - Ultraviolet detecting element, and apparatus and method for measuring ultraviolet ray - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more easily detect ultraviolet rays, suppressing an influence of an oxidizing gas existing in the atmosphere. <P>SOLUTION: A detecting agent solution 101 wherein indigo carmine, citric acid, and glycerol are dissolved in water as coloring matters, is prepared, and the prepared detecting agent solution 101 is put in a container 102. A carrier sheet 103 composed of filter paper is dipped in the detecting agent solution 101 to impregnate the carrier sheet 103 with the detecting agent solution. Then, the carrier sheet 103 dipped in the detecting agent solution 101 for about thirty seconds is taken out from the detecting agent solution 101, and the taken-out carriage sheet 103 is dried by wind to produce a detecting sheet 103a. Then, the detecting sheet 103a is put in a resin bag 141, and the bag 141 is sealed, to form a detecting element 104 in a state that the detecting sheet 103a is enclosed in the bag 141. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultraviolet ray detection element, an ultraviolet ray measuring apparatus and method used for detecting ultraviolet rays.

  It is well known that exposure to a large amount of ultraviolet rays causes severe sunburn and skin cancer, and has an adverse effect on the human body. In addition, since the ozone layer decrease was observed in the 1970s, the ozone layer has been decreasing globally, and the amount of ultraviolet rays reaching the ground has increased. There is a growing need for quantitative measurements.

Conventionally, there has been known an ultraviolet radiometer that splits ultraviolet light from sunlight with a UV filter, converts the split ultraviolet light into an electrical signal with a light receiver, and converts the converted electrical signal into a digital signal for display and recording. Yes. However, the above ultraviolet radiometer has a problem that its structure is complicated and expensive, and it is not so popular for individuals. In addition, an ultraviolet indicator (for example, an ultraviolet indicator “UV label” manufactured by Kousui Giken Kogyo Co., Ltd.) in which a dye that changes color by ultraviolet rays is held on a carrier is commercially available (see Non-Patent Document 1).

Daisuke Harumoto et al. “UV Indicator“ UV Label ””, Annual Meeting of the Japan Society for Antibacterial and Antifungal Society, Vol. 27th, p. 34, Life Sciences, 2000.

  However, products that use dyes to achieve a function that changes color due to ultraviolet exposure can cause discoloration even with oxidizing gases such as ozone, so it is not possible to accurately assess the amount of UV exposure in areas with high ozone concentrations in the atmosphere. There was a problem.

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to more easily detect ultraviolet rays while suppressing the influence of an oxidizing gas present in the atmosphere. And

  The ultraviolet detection element according to the present invention includes a sheet-like detection sheet carrying a detection agent containing a dye that changes light absorption in the visible region in response to ultraviolet light, and a plastic film that covers the detection sheet and transmits ultraviolet light. With. Therefore, the dye carried on the detection paper is suppressed from being exposed to the gas in the atmosphere in which the detection element is arranged.

  In the ultraviolet detection element, the dye has an indigo ring such as indigo or indigo carmine, and the detection agent only needs to include a dye, an acid such as citric acid, and glycerin. The plastic film may be a film made of polyethylene and having a thickness of 40 μm.

  The ultraviolet ray measuring apparatus method according to the present invention includes a sensing element, a light emitting part that emits light of a predetermined wavelength to the sensing element, and reflected light that is emitted from the light emitting part and reflected by the sensing element. It has at least a light detection unit that receives light and outputs an electrical signal corresponding to the received light amount, and an electric meter that measures the state of the electrical signal output by the light detection unit, and the detection element reacts with ultraviolet rays to be visible region It comprises a sheet-like detection sheet carrying a detection agent containing a dye whose light absorption changes, and a plastic film that covers the detection sheet and transmits ultraviolet rays.

  In the ultraviolet ray measuring apparatus, the light emitting unit is composed of a light emitting diode, the light detecting unit is composed of a phototransistor, and in addition, a battery for supplying power to the light emitting diode and the phototransistor, and a light emitting diode and a phototransistor from the battery A switch for turning on and off the power supply of the voltmeter, a voltmeter as an electric meter connected between the phototransistor and the battery, and a light emitting diode, a phototransistor, a battery, a switch, and a voltmeter What is necessary is just to provide the terminal board provided with the terminal and the board | substrate which has arrange | positioned the light emitting diode, the phototransistor, the battery, the switch, the voltmeter, and the terminal board.

  Further, the ultraviolet ray measuring method according to the present invention includes a detection element in which a sheet-like detection sheet carrying a dye that changes light absorption in the visible region in response to ultraviolet light is covered with a plastic film that transmits ultraviolet light. A step of preparing, a step of obtaining a first absorbance by the reflected light of the detection sheet, a step of exposing the detection element to an environment irradiated with ultraviolet light for a predetermined time, and a second of the reflected light of the detection element exposed to the ultraviolet light for a predetermined time And a step of calculating an irradiation amount of ultraviolet rays irradiated to the detection element based on a difference between the first absorbance and the second absorbance.

  As described above, according to the present invention, the detection sheet carrying the detection agent containing the dye that changes the light absorption in the visible region by reacting with the ultraviolet ray is covered with the plastic film that transmits the ultraviolet ray. In addition, an excellent effect that ultraviolet rays can be detected more easily in a state where the influence of an oxidizing gas present in the atmosphere is suppressed can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that, in the drawings shown below, the same reference numerals are used for those having the same function, and repeated description is omitted.

  First, a method for manufacturing an ultraviolet detection element according to the present embodiment will be described with reference to FIGS. First, as shown in FIG. 1A, a detection agent solution 101 in which indigo carmine, citric acid, and glycerin are dissolved in water as pigments is prepared, and the prepared detection agent solution 101 is stored in a container 102. For example, 0.045 g of indigo carmine, 3.5 g of citric acid, and 12.5 g of glycerin are dissolved in pure water so that the total amount becomes 50 ml, and this may be used as the detection agent solution 101.

  Next, as shown in FIG. 1B, a carrier sheet 103 made of filter paper is immersed in the detection agent solution 101, and the carrier sheet 103 is impregnated with the detection agent solution. For example, the carrier sheet 103 is filter paper No. manufactured by Advantech Toyo. 2 is sufficient. The carrier sheet 103 may be immersed in the detection agent solution 101 for about 30 seconds. Next, the carrier sheet 103 immersed in the detection agent solution 101 for about 30 seconds is taken out from the detection agent solution 101, and the taken out carrier sheet 103 is air-dried. Next, as shown in FIG. 1C, the taken-out carrier sheet 103 is left to dry in a nitrogen gas stream for 24 hours or more to produce a detection sheet 103a. The detection sheet 103 a is configured by supporting (holding) the above-described components dissolved in the detection agent solution 101 on the carrier sheet 103. The carrier sheet 103 is not limited to filter paper, and may be any sheet having a structure in which fibers such as cloth are entangled and capable of carrying a detection agent.

  Next, as shown in FIG. 1D, the detection sheet 103a is accommodated in, for example, a resin bag 141 that transmits ultraviolet rays, and the bag 141 is sealed, as shown in FIG. In addition, the detection element 104 in which the detection sheet 103a is sealed in the bag 141 is formed. The detection element 104 is a state in which the detection sheet 103a is covered with a bag 141 as a plastic film. For example, by enclosing the detection sheet 103a in the bag 141 under a reduced pressure environment, the bag 141 is prevented from being mixed with gas such as air.

  Moreover, the bag 141 should just be comprised from the sheet-like or film-like resin material which the ultraviolet-ray of a UVA area | region (wavelength 400-320 nm) and a UVB area | region (wavelength 320-280 nm) permeate | transmits. For example, a film made of a polyethylene film having a thickness of 40 μm (“Unipack A-4” manufactured by Production Japan Co., Ltd.) may be used. If it is the bag 141 comprised from the polyethylene film of thickness 40 micrometers, it can be set as the state which permeate | transmits an ultraviolet-ray in the state which permeation | transmission of oxidizing gas, such as ozone, was suppressed.

Next, an ultraviolet detection method using the detection element 104 will be described with reference to FIGS. 1 (f) and 1 (f ′). In the measurement of ultraviolet rays using the detection element 104, first, as shown in FIG. 1E, the intensity of the reflected light that is irradiated with light source light (incident light intensity I ₀ ) from a predetermined light source and reflected from the detection sheet 103a. (Reflected light intensity I) is measured. This optical measurement is performed twice immediately after the detection element 104 is manufactured (before exposure to ultraviolet rays) and after the detection element 104 is exposed to ultraviolet rays. By comparing the results of these two optical measurements, Perform detection. The exposure to ultraviolet rays is performed by the detection element 104 in which the detection sheet 103a is enclosed in the bag 141, and the above two optical measurements are performed by the detection sheet 103a alone as shown in FIG. It may be. In the optical measurement using the reflected light as described above, the absorbance is indicated by log ₁₀ (I ₀ / I).

Hereinafter, measurement results of ultraviolet rays using the detection element 104 will be described. First, the sensing element 104 is exposed to UV light in the UVA region at 80 watt hours / m ^{2, and} exposed to UV light in the UVB region at 1.0 watt hour / m ² , before and after exposure from the bag 141 of the sensing element 104. The detection sheet 103a was taken out and the reflected light was measured (twice) as described above. The results of these two measurements (absorbance analysis) are shown in FIG. In FIG. 2, the dotted line is the measurement result of the absorbance before exposure to ultraviolet rays, and the solid line is the measurement result after exposure to ultraviolet rays. In this measurement, the optical measurement is performed by the detection sheet 103a alone, but the present invention is not limited to this. Since the bag 141 transmits light in a wavelength region (500 to 700 nm) used for optical measurement, the optical measurement may be performed in the state of the detection element 104 as described above.

  Explaining the detection result of ultraviolet rays, as shown in FIG. 2, there is a large difference between the solid line and the dotted line in the wavelength range of 500 to 700 nm, particularly in the vicinity of 620 nm. In the measurement of the absorbance after exposing the detection element 104 to ultraviolet rays (solid line), the absorption near the wavelength of 620 nm decreases. From this result, when the detection element 104 is exposed to ultraviolet rays, the pigment (indigo carmine) contained in the detection element 104 (detection sheet 103a) is decomposed, and a new decomposition product is generated. This product can be presumed that the C═C bond contained in the molecular skeleton of indigo carmine was decomposed.

  In this way, by measuring the absorption spectrum of the detection element 104 with a spectrophotometer (absorptiometer), it is possible to perform quantitative measurement of molecules generated by the decomposition of the dye. Moreover, since the degree to which the dye is decomposed depends on the amount of exposed ultraviolet rays, the amount of ultraviolet radiation exposure can be indirectly measured by quantitative measurement of the generated molecules. Here, as shown in FIG. 2, in the result of the measurement of the absorbance (optical measurement), the change in absorbance is as high as about 0.18 before and after the exposure to ultraviolet rays in the vicinity of a wavelength of 620 nm. It turns out that it is possible enough.

  In the above description, the case where indigo carmine is used as a dye that changes the light absorption in the visible region by reacting with ultraviolet rays has been described. You may do it. In the above description, a bag made of polyethylene is used. However, the present invention is not limited to this. For example, a film made of another plastic material such as polystyrene or polypropylene may be used. Further, in the above description, the filter paper is immersed in the produced detection agent solution, and the filter paper is impregnated with the detection agent solution. However, the present invention is not limited to this. You may make it impregnate.

  Next, a sunlight exposure experiment using the detection element 104 will be described. In this experiment, in addition to the measurement by the detection element 104, the UV meter for measuring the UVA light amount and the UV meter for measuring the UVB light amount simultaneously measure the UVA light amount and the UVB light amount of the irradiated sunlight. To do. As is well known, sunlight contains ultraviolet radiation in both the UVA and UVB regions. FIG. 3 shows the measurement results of these light amounts and the difference in absorbance of the sensing element 104 before and after exposure at this light amount. As shown in FIG. 3, as the amount of light measured by the UV meter increases, the difference in absorbance between before and after exposure at a predetermined wavelength (620 nm) of the sensing element 104 increases. As a result, it can be seen that when the amount of exposure to ultraviolet rays increases, the reflectance of light at a predetermined wavelength (620 nm) of the detection element 104 increases (absorbance decreases).

  Next, the light transmission characteristics of the bag 141 shown in the figure will be described. When the absorption spectrum of the transmitted light of the bag 141 made of a polyethylene film having a thickness of 40 μm is measured and the transmittance is calculated from the measurement result, about 80% of the ultraviolet rays in the UVA and UVB regions are transmitted as shown in FIG. ing. Since the ultraviolet transmittance depends on the thickness of the film (polyethylene) constituting the bag 141, the sensitivity can be adjusted flexibly by changing the thickness of the film. In addition, although the transmittance | permeability of an ultraviolet-ray improves and it becomes possible to improve a sensitivity, so that the thickness of a film is thinned, it becomes difficult to suppress entrance of oxidizing gas, such as ozone. When the polyethylene film is used, if the thickness is about 40 μm, the entry of the oxidizing gas can be suppressed while maintaining the desired ultraviolet transmittance.

  Further, a gas permeation experiment of the bag 141 was performed. In this gas permeation experiment, first, 100 ppb of ozone gas is supplied into the desiccator from the ozone generator, and this is continued for 24 hours to expose the sensing element 104 to the ozone gas. The absorbance of the sensing element 104 is measured before and after such ozone gas exposure. In this gas permeation experiment, the difference in absorbance at the sensing element 104 was below the detection limit before and after exposure to ozone gas. From this, it was confirmed that the polyethylene bag 141 has a sufficient gas blocking function. Therefore, it is possible to remove the influence of the oxidizing gas in the atmosphere by using a polyethylene bag (film).

  Next, an ultraviolet measurement device using the above-described sensing element 104 will be described. FIG. 5 is a configuration diagram illustrating a configuration example of an ultraviolet ray measuring apparatus using the detection element 104. For example, the detection element 104 is irradiated with light emitted from a light emitting unit 501 including an LED that emits light of a predetermined wavelength. Reflected light from the detection element 104 is received by the light receiving unit 503. The light receiving unit 503 receives reflected light, photoelectrically converts the received light, and outputs a signal current. The conversion amplification unit 504 amplifies the signal current output from the light receiving unit 503 and performs current-voltage conversion. The A / D conversion unit 505 converts the voltage signal output from the converted image antinode 504 into a digital signal. The digital signal output from the A / D conversion unit 505 is output from the output detection unit 506 as a detection result.

Here, for the light emitting unit 501, for example, a red LED having an emission wavelength of 620 nm may be used. The light receiving unit 503 is, for example, a photodiode. As this photodiode, for example, if a photodiode sensitive to a wavelength in the range of 500 to 700 nm is used, it corresponds to a wavelength with a large change in the absorption spectrum of the detection element 104. Using the measures shown in FIG. 5, the ultraviolet rays were measured by exposure to ultraviolet rays having a UVA region of 80 watt-hour / m ² and a UVB region of 1.0 watt-hour / m ² . As a result of this measurement, different outputs are obtained from before and after exposure to ultraviolet rays from the apparatus shown in FIG. 5 (output detection unit 506), similarly to the result shown in FIG. In this way, the ultraviolet exposure amount quantification device can be configured easily.

  Next, the ultraviolet ray measuring apparatus according to the embodiment of the present invention will be described in more detail. FIG. 6 is a configuration diagram showing a configuration example of an ultraviolet ray measuring apparatus. First, an LED 602 that emits red light having a wavelength of 620 nm and a photosensitivity in a wavelength range of 400 to 1100 nm in a substrate 601 of about 12 cm × 6 cm. The phototransistor 603 having the above and the detection element 104 are disposed. The light emitting surface of the LED 602 and the light receiving surface of the phototransistor 603 are arranged so as to face the direction of the sensing element 104 so that the light emitted from the LED 602 is reflected by the sensing element 104 and then received by the phototransistor 603. , Adjust each angle.

  A terminal plate 605, a battery 606, and a switch 607 are provided on the substrate 601. The LED 602 and the phototransistor 603 are configured to be supplied with power from two AA batteries 606 connected in series via a terminal plate 605. The power supply is configured to be turned on / off by a switch 607. Thus, the circuit is assembled using the terminals of the terminal plate 605. For example, the wiring of the phototransistor 603 is connected to the terminal number T1, the wiring of the switch 607 is connected to the terminal number T2, the wiring of the LED 602 is connected to the terminal number T3, and the wiring of the switch 607 and the battery 606 is connected to the terminal number T4. A battery 606, LED 602, and a phototransistor 603 are connected to terminal number 5. The resistor 608 is connected between the terminal T2 and the terminal T3 so that the output voltage from the phototransistor 603 is on the order of one digit (V), and the resistor 609 is connected between the terminal T1 and the terminal T2. It is connected.

  In the state shown in FIG. 6, the sensing element 104 was exposed in the apparatus shown in FIG. 6 by measuring the voltage by connecting a voltmeter between the terminal number T1 and the terminal number T2 of the terminal plate 605 in the wired state. The amount of ultraviolet rays is measured. As described above, according to the apparatus shown in FIG. 6, an ultraviolet ray measuring apparatus can be configured in a small area. In addition, since a commercially available battery can be used as a power source, the amount of ultraviolet radiation exposure can be determined more easily.

  As described above, the ultraviolet light detection element according to the present invention is composed of a carrier sheet made of filter paper or the like carrying a dye that reacts with ultraviolet light and decomposes, and a plastic film covering the carrier sheet. . As described above, in the present sensing element, the carrier sheet carrying the dye is covered with the plastic film through which the ultraviolet rays are transmitted, so that the oxidizing gas can be prevented from entering the dye, and the dye is in the atmosphere. Ultraviolet rays can be detected without being affected by oxidizing gas. In addition, since the absorption wavelength in the visible region changes, the ultraviolet ray detection element does not use the ultraviolet ray quantification device, and even if it is used alone, it is possible to know a rough ultraviolet ray exposure amount by visual observation.

It is explanatory drawing explaining the detection element of an ultraviolet ray concerning this Embodiment, and the manufacturing method of this detection element. It is a characteristic view which shows the measurement result by the detection element shown in FIG. It is a characteristic view which shows the measurement result of the light quantity of both the area | region of UVA and UVB which sunlight contains, and the difference of the light absorbency of the detection element 104 before and behind the exposure in this light quantity. It is a characteristic view which shows the transmittance | permeability computed from the result of having measured the absorption spectrum of the transmitted light of the bag 141 which consists of a 40-micrometer-thick polyethylene film. It is a block diagram which shows the structural example of the ultraviolet-ray measuring apparatus using the detection element 104. FIG. It is a block diagram which shows the structural example of the ultraviolet-ray measuring apparatus using the detection element 104. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Detection agent solution, 102 ... Container, 103 ... Carrier sheet, 103a ... Detection sheet, 104 ... Detection element, 141 ... Bag.

Claims (6)

A sheet-like detection sheet carrying a detection agent containing a dye that changes its light absorption in the visible region in response to ultraviolet light; and
An ultraviolet detection element comprising: a plastic film that covers the detection sheet and transmits ultraviolet light. In the ultraviolet detection element according to claim 1,
The dye has an indigo ring, and the detection agent includes the dye, an acid, and glycerin. In the ultraviolet detection element according to claim 1 or 2,
The ultraviolet ray detecting element, wherein the plastic film is a film made of polyethylene and having a thickness of 40 nm. A sensing element;
A light emitting unit that emits light of a predetermined wavelength to the sensing element;
A light detection unit that receives reflected light emitted from the light emitting unit and reflected from the detection element, and outputs an electrical signal corresponding to the received light amount;
And at least an electric meter that measures the state of the electric signal output by the light detection unit,
The sensing element is
A sheet-like detection sheet carrying a detection agent containing a dye that reacts with ultraviolet rays to change light absorption in the visible region;
An ultraviolet ray measuring apparatus comprising: a plastic film that covers the detection sheet and transmits ultraviolet rays. The ultraviolet ray measuring apparatus according to claim 4,
The light emitting unit is composed of a light emitting diode,
The photodetection unit is composed of a phototransistor,
in addition,
A battery for supplying power to the light emitting diode and the phototransistor;
A switch for turning on and off the power supply from the battery to the light emitting diode and the phototransistor;
A voltmeter as an electric meter connected between the phototransistor and the battery;
A terminal plate comprising terminals for connecting each of the light emitting diode, the phototransistor, the battery, the switch, and the voltmeter;
An ultraviolet ray measuring apparatus comprising: the light emitting diode, the phototransistor, the battery, the switch, the voltmeter, and a substrate on which the terminal plate is disposed. A step of preparing a detection element in which a sheet-like detection sheet carrying a dye that changes light absorption in the visible region by reacting with ultraviolet rays is covered with a plastic film that transmits ultraviolet rays;
Obtaining a first absorbance by reflected light of the detection sheet;
Exposing the sensing element to an environment irradiated with ultraviolet light for a predetermined time;
Obtaining a second absorbance due to the reflected light of the sensing element exposed to ultraviolet light for a predetermined time;
And a step of calculating an irradiation amount of ultraviolet rays irradiated to the detection element based on a difference between the first absorbance and the second absorbance.

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