JP2018100310A - X-ray recording material, method for producing x-ray recording material, x-ray recording medium, recording method using x-ray recording medium, and method of measuring x-ray irradiance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray recording material that can be used repeatedly and has durability, featuring excellent practical utility, a method for producing the X-ray recording material, an X-ray recording medium, a recording method using the X-ray recording medium, and a method of measuring an X-ray irradiance.SOLUTION: A photochromic material, which is an X-ray recording material of the present invention, has a composition represented by the following formula (a): Ba(MgFeAl)(SiB) O(where 0≤x<0.01, 0≤y<0.10, 0≤z<0.20). The material is based on a barium magnesium silicate having a skeleton of SiO-MgOnetwork structure.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an X-ray recording material, a method for producing an X-ray recording material, an X-ray recording medium, a recording method using an X-ray recording medium, and a method for measuring an X-ray irradiation amount. Specifically, the X-ray recording material that can be used repeatedly, has durability, and has excellent practicality, a method for producing the X-ray recording material, an X-ray recording medium, a recording method using the X-ray recording medium, and measurement of the X-ray irradiation amount It concerns the method.

  Radiation imaging techniques including X-rays are widely used. In particular, X-ray imaging technology is used in a wide range of fields such as non-destructive inspection, medical diagnosis, film batch, and autoradiography.

  For example, X-ray imaging techniques include an X-ray film, an imaging plate, and an X-ray camera.

  The X-ray film increases the content of silver halide, which is a photosensitive substance, compared with ordinary photographic films, and obtains sufficient sensitivity and contrast for X-ray irradiation. In addition, by using together with fluorescent intensifying screens, higher sensitivity is realized.

  The imaging plate is formed by applying microcrystals of photostimulable phosphor to a sheet or the like as a support. When the surface exposed to X-rays is irradiated with helium neon laser light, light emission corresponding to the X-ray exposure amount occurs, and by measuring this light emission amount, an X-ray image proportional to the X-ray irradiation amount can be acquired. .

  The X-ray camera can detect the incident position and measure the energy of incident X-rays using a CCD or CMOS as a photosensitive element.

  Here, the X-ray film is excellent in cost and can be used even in a severe use environment, but cannot be used repeatedly. In addition, instant properties are difficult because a film development process is required.

  In addition, the imaging plate has the advantage that it can be used repeatedly and digital image data can be obtained. However, the imaging plate is not suitable for in-situ imaging because a dedicated and expensive reading device is required.

  X-ray cameras are suitable for precision shooting with video shooting and high dynamic range, but the equipment is expensive and precise electronic components are used, so the usage environment and scenes are limited. It has become.

  Among the uses of X-ray imaging technology, there is a strong demand for the development of simple imaging technology that can be used repeatedly in the field such as non-destructive inspection, is cost-effective, and can immediately confirm X-ray transmission images. .

  Under these circumstances, a technique that uses an organic photochromic material as a recording medium and attempts to solve the problems of existing X-ray imaging techniques has been proposed. For example, there are photochromic compositions described in Patent Document 1 and Patent Document 2.

  In Patent Document 1 and Patent Document 2, an organic photochromic material is used instead of silver halide used in an X-ray film. A photochromic material is a material that exhibits a kind of reversible property, that is, photochromism, which changes color when a substance is irradiated with light, and reverses color when irradiated or heated to a substance that has changed color.

  Photochromic materials have already been put to practical use in sunglasses and the like, and in future, application to optical memories, switching elements, optical elements, light control glasses, color displays, and the like are being studied.

  Patent Document 1 and Patent Document 2 propose a radiation indicator that can be used repeatedly using a photochromic material made of an organic material.

Japanese Patent Laying-Open No. 2005-8753 JP 2005-8754 A

  However, since the photochromic materials described in Patent Document 1 and Patent Document 2 are composed of organic materials, the chemical and thermal stability is low, and the chemical species itself is likely to deteriorate due to repeated isomerization. There was a problem such as.

  In addition, some organic materials do not cause photochromic phenomenon after crystallization or dispersion in a polymer even if photochromic phenomenon occurs in a liquid state. Sometimes.

  The present invention was devised in view of the above points, and can be used repeatedly, has durability, is excellent in practicality, a method for producing an X-ray recording material, an X-ray recording medium, It is an object of the present invention to provide a recording method using an X-ray recording medium and a method for measuring an X-ray irradiation dose.

  In order to achieve the above object, the X-ray recording material of the present invention contains a silicate compound exhibiting photochromic properties.

  Here, the silicate compound exhibiting photochromic properties can be repeatedly attached and detached by X-ray irradiation and heating. In addition, it is composed of an inorganic material and has a chemically and thermally stable structure. Furthermore, it is not necessary to dissolve in a solvent as in the case of organic substances, and it can be used as a solid. The photochromic property here includes not only coloring by X-rays and decoloring by heating but also coloring by ultraviolet rays and decoloring by visible light.

Further, when the silicate compound contains at least barium and magnesium, it has a basic structure of tetrahedral SiO ₄ and MgO ₄ and a crystal structure in which Ba is inserted into voids of these basic skeletons.

Further, when at least a part of Si and Mg of the SiO ₄ —MgO ₄ network structure constituting the skeleton of the silicate compound is substituted with at least one element selected from Fe, B, or Al, the composition Can improve the photochromic characteristics. More specifically, when Mg is substituted with Fe or Al, it contributes to an improvement in sensitivity to X-rays, an improvement in coloring strength, and an extension of the holding time of the colored state. Further, when Si is substituted with B, it contributes to an improvement in coloring strength.

  In order to achieve the above object, the method for producing an X-ray recording material of the present invention comprises a powdery material containing a silicate compound exhibiting photochromic properties in a reducing atmosphere of 1150 ° C. to 1300 ° C. for 2 hours. The process of baking is provided.

  Here, the silicate compound exhibiting photochromic properties can be repeatedly attached and detached by X-ray irradiation and heating. In addition, it is composed of an inorganic material and has a chemically and thermally stable structure. Furthermore, it is not necessary to dissolve in a solvent as in the case of organic substances, and it can be used as a solid.

  Moreover, it becomes possible to fully form the crystal phase which shows photochromic property by baking a powdery body at 1150 degreeC-1300 degreeC.

  Here, when the powdery body is fired at a temperature of less than 1150 ° C., the target crystal phase may not be formed or may be formed only insufficiently. On the other hand, when the powdery body is fired at a temperature exceeding 1300 ° C., the target crystal phase is not formed or the material is melted.

  In addition, by firing the powdery body in a reducing atmosphere, lattice defects that cause photochromic functionality are easily formed in the crystal structure of the fired product.

  In addition, by firing the powdery body for 2 hours or more, a crystal phase exhibiting photochromic properties can be sufficiently grown. When the firing time is less than 2 hours, sufficient grain growth and chemical reaction are not achieved, and it becomes difficult to obtain the target crystal phase and function.

  In order to achieve the above object, the X-ray recording medium of the present invention has a recording layer in which an X-ray recording material containing a silicate compound exhibiting photochromic properties is uniformly blended and is rewritable. It is configured.

  Here, an image obtained by irradiating X-rays can be recorded by having a recording layer in which an X-ray recording material containing a silicate compound exhibiting photochromic properties is uniformly blended. That is, for example, an object is placed between an X-ray generation source and a recording layer and irradiated with X-rays, whereby a transmitted X-ray image inside the object can be obtained.

  Moreover, the X-ray recording material containing the silicate compound which shows photochromic property was mix | blended, and it was comprised so that rewriting was possible, and the X-ray image obtained by coloring can be erase | eliminated and it can be used repeatedly.

  In addition, when the X-ray irradiation fluoresces and at least part of the wavelength range of the emission spectrum contains a scintillator that overlaps the wavelength range of the absorbance spectrum exhibited by the silicate compound, the sensitivity to X-rays is increased. This can be further improved. That is, the scintillator irradiated with X-rays generates light of a certain wavelength, and the silicate compound absorbs the emitted light, which works favorably for coloring.

  In order to achieve the above object, the recording method using the X-ray recording medium of the present invention is an X-ray recording material containing a silicate compound exhibiting photochromic properties, and is configured to be decolored by heating. The X-ray recording medium is colored by irradiation with X-rays having a wavelength in the range of 0.001 to 10 nm.

  Here, an X-ray recording medium composed of an X-ray recording material containing a silicate compound exhibiting photochromic properties is irradiated with X-rays having a wavelength in the range of 0.001 to 10 nm to color the X-rays. The recording material can be colored by irradiation to obtain and record an X-ray image. Further, the recording medium is composed of an inorganic material, and chemical and thermal stable recording is possible.

  Further, an X-ray recording material containing a silicate compound exhibiting photochromic properties, and an X-ray image recorded on the recording material can be erased by an X-ray recording medium configured to be decolored by heating, and repeated recording Is a possible method.

  In order to achieve the above object, the X-ray irradiation measuring method of the present invention is applied to an X-ray recording medium comprising an X-ray recording material containing a silicate compound exhibiting photochromic properties at a wavelength of 0. A coloring step of irradiating and coloring X-rays in the range of 001 to 10 nm, and a detecting step of detecting the X-ray irradiation amount from the coloring amount of the X-ray recording material obtained in the coloring step.

  Here, the X-ray recording medium composed of an X-ray recording material containing a silicate compound exhibiting photochromic properties is irradiated with X-rays in the wavelength range of 0.001 to 10 nm to color the X-rays. The recording material can be colored by this irradiation, and information on the coloring amount for calculating the X-ray irradiation amount to be detected can be obtained.

  Further, a simple X-ray irradiation amount to be detected can be measured by a detection step of detecting the X-ray irradiation amount from the coloring amount of the X-ray recording material obtained in the coloring step. More specifically, a calibration curve between the X-ray irradiation amount and the coloring amount in the X-ray recording material is prepared in advance, and the target X-ray irradiation amount is calculated from the coloring amount and the calibration curve recorded in the recording material. Can be decided.

The X-ray recording material according to the present invention is reusable and durable, and has excellent practicality.
In addition, the method for producing an X-ray recording material according to the present invention is capable of producing an X-ray recording material that can be used repeatedly, has durability, and has excellent practicality.
The X-ray recording medium according to the present invention is reusable and durable, and has excellent practicality.
In addition, the method for producing an X-ray recording medium according to the present invention can produce an X-ray recording medium that can be used repeatedly, has durability, and is highly practical.
Furthermore, the method for measuring an X-ray irradiation amount according to the present invention provides a method for measuring an X-ray irradiation amount that can be used repeatedly, has durability, and has excellent practicality.

It is the schematic (a) which shows an example of an apparatus structure for obtaining an X-ray transmission image, and the schematic (b) which shows the condition of image acquisition. It is an absorption spectrum of Example 1 after coloring by X-ray irradiation and after decoloring by heating. It is a graph which shows the peak intensity of wavelength 520nm in Example 1 which repeated coloring and decoloring. It is a graph which shows the relationship between the irradiation time in Example 1 at the time of irradiating by changing the output of X-ray | X_line, and the light absorbency of wavelength 520nm. It is a graph which shows the relationship between the elapsed time after coloring of Examples 2-4 and the light absorbency in wavelength 520nm. It is the graph which displayed the result shown in FIG. 5 by common logarithm. It is an absorption spectrum after coloring of Examples 2-8.

  Hereinafter, embodiments of the present invention will be described in detail to provide an understanding of the present invention.

(Photochromic material)
The photochromic material that is the X-ray recording material of the present invention has the following formula (a):
_{Ba (Mg 1-x-y} Fe x Al y) (Si 1-z B z) O 4 ··· (a)
(In the formula, 0 ≦ x <0.01, 0 ≦ y <0.10, and 0 ≦ z <0.20.)
It has the composition represented by these. This material is based on barium magnesium silicate having a skeleton with a SiO ₄ —MgO ₄ network structure.

In this substance, silicon ions (Si ⁴⁺ ) in the SiO ₄ tetrahedron are replaced with magnesium ions (Mg ²⁺ ) at a certain ratio. Magnesium ions (Mg ²⁺ ) are sites where iron ions (Fe ²⁺ ) and aluminum ions (Al ³⁺ ) are bonded. Further, silicon ions (Si ⁴⁺ ) are sites to which boron ions (B ³⁺ ) are bonded.

  By having the composition represented by the above formula (a), the substance exhibits a photochromic property of coloring purple-red with respect to X-ray irradiation in the wavelength range of 0.001 nm to 10 nm. The substance is colored not only by X-ray irradiation but also by ultraviolet irradiation.

  Moreover, since it is comprised with an inorganic material, it becomes a chemically and thermally stable structure, and has high durability. Furthermore, it is not necessary to dissolve in a solvent like an organic substance, and it can be used as a solid.

  This substance has high heat resistance in a colored state by X-ray irradiation, and can maintain a discolored state up to about 100 ° C., for example. Further, the colored state can be maintained for a long time, for example, several hundred days.

  In addition, the original material colored by X-ray irradiation can be decolorized again by irradiating with green light (for example, wavelength 532 nm) or heating. For this reason, the X-ray recording material can be used repeatedly. Furthermore, even if coloring and decoloring are repeated in this substance, sufficient coloring strength is obtained and it is difficult to deteriorate. This point will be described in detail in the embodiments described later.

  X in the above formula (a) is preferably in the range of 0 ≦ x <0.01. Further, y is preferably in the range of 0 ≦ y <0.10. Within the range in the formula (a), the photochromism characteristics of the X-ray recording material can be improved.

  More specifically, when Mg is substituted with Fe or Al within the above range, the sensitivity to X-rays and the coloring strength of the X recording material are improved. Moreover, the retention time of the colored state after X-ray irradiation is extended.

  Z in the formula (a) is preferably in the range of 0 ≦ z <0.20. Within the range in the formula (a), the photochromism characteristics of the X-ray recording material can be improved.

  More specifically, when Si is substituted with B within the above range, the coloring strength is improved.

Moreover, in this substance, it is preferable that the strongest X-ray peak intensity of the BaMgSiO ₄ phase is twice or more the X-ray peak intensity of the other crystal layers.

The composition represented by the above formula _{(a), Ba (Mg 1} -x-y Fe x Al y) (Si 1-z Bz) O 4, BaMg (Si 1-z Bz) O 4, Ba (Mg 1 _{-y Al y) (Si 1-} z Bz) O 4, Ba (Mg 1-x Fe x) SiO 4, BaMgSiO 4, structure of _{Ba (Mg 1-y Al y} ) SiO 4 and the like.

  As each raw material of the composition represented by the above formula (a), examples of the raw material containing Ba element include barium carbonate, barium sulfate, barium oxide, barium nitrate, barium hydroxide, barium silicide, and barium borate. Examples of the raw material containing Mg element include magnesium carbonate and magnesium oxide. Examples of the raw material containing Si element include silicon and silicon oxide.

  Furthermore, examples of the raw material containing the O element include the various oxides described above. Examples of the raw material containing Fe element include iron oxides having various oxidation numbers. Examples of the raw material containing Al include aluminum oxide and aluminum acetate. The mixture of photochromic materials may further contain other substances in addition to the above raw materials as long as the photochromism is not inhibited.

  The X-ray recording material of the present invention can contain a scintillator in addition to the photochromic material. A scintillator is a phosphor that emits an arbitrary wavelength in response to X-ray irradiation.

  The photochromic material represented by the above formula (a) has the maximum sensitivity to light having a wavelength of 250 nm, and this sensitivity is higher than the sensitivity to X-ray irradiation.

  Therefore, the sensitivity of the X-ray recording material to X-ray irradiation can be improved by using a scintillator that emits fluorescence in a wavelength band including 250 nm when irradiated with X-rays together with the photochromic material.

  That is, in the absorbance spectrum of the photochromic material and the emission spectrum with respect to the X-ray irradiation of the scintillator, by selecting a scintillator in which the spectra overlap and the overlap is large, the sensitivity of the X recording material to X-rays is selected. It will work in favor of.

Examples of the scintillator used in combination with the photochromic material represented by the above formula (a) include pure cesium iodide (CsI: emission peak wavelength 315 nm) and barium fluoride (BaF ₂ : emission peak wavelengths 210 nm, 310 nm). Note that the type of scintillator is not limited to this, and can be appropriately selected as long as the sensitivity to X-rays can be improved.

(Method for producing X-ray recording material)
The X-ray recording material of the present invention is produced by baking a powdery material containing a photochromic material having the composition represented by the above formula (a) in a reducing atmosphere at 1150 ° C. to 1300 ° C. for 2 hours or more.

  It is presumed that by firing the above-mentioned powdery photochromic material in a reducing atmosphere, lattice defects are generated in the crystal structure of the fired product and contribute to photochromism.

  In the firing step, for example, by adding boric acid to the photochromic material, the processing can be performed in a reducing atmosphere. The content of boric acid to be added is not particularly limited, but is in the range of 2 to 10 mol% with respect to the Ba contained in the raw material containing Ba in the photochromic material represented by the above formula (a). An amount is preferred.

  The photochromic material represented by the above formula (a) may further be mixed with a solvent such as ethyl alcohol so that the raw materials and boric acid are more uniformly mixed. In addition, the mixing method of each raw material, boric acid, a solvent, etc. is sufficient if it is a method by which a uniform mixture is obtained, and the kind of mixing method is not specifically limited.

  The step of firing the powder containing the photochromic material is more preferably performed in a reducing atmosphere, and more preferably in the presence of hydrogen gas. Specific examples of the firing method include a method of firing the mixture in a mixed gas stream of an inert gas such as argon gas and a reducing gas such as hydrogen gas.

  The concentration of hydrogen gas in the mixed gas is preferably in the range of 2 to 10% by volume. Moreover, as baking conditions, the conditions baked for 2 hours at 1150 degreeC-1300 degreeC are mentioned. By performing the firing treatment under these conditions, a fired product in which a crystal phase exhibiting photochromic properties is sufficiently formed can be obtained. A commercially available apparatus can be used as the baking apparatus.

  Here, the firing conditions are not necessarily limited to the temperature range of 1150 ° C to 1300 ° C. However, in the photochromic material represented by the above formula (a), it is preferable that the firing condition is in a temperature range of 1150 ° C. to 1300 ° C. from the viewpoint that the material is not easily melted and a crystal phase exhibiting photochromic properties can be sufficiently formed. .

  Further, the firing conditions are not necessarily limited to the conditions of firing at 1150 ° C. to 1300 ° C. for 2 hours. However, from the viewpoint that the content of impurities in the raw materials and intermediate products can be reduced and a crystal phase exhibiting photochromic properties can be sufficiently formed, it is preferable that the firing condition is a condition of firing at 1150 ° C. to 1300 ° C. for 2 hours.

  As the X-ray recording material, a fired product of a powdery body formed so as to have a certain shape such as a plate shape can be used as it is. In this case, the shape after firing is not particularly limited, and can be appropriately selected according to the size and shape of an object for which an X-ray transmission image is desired.

  In addition, the X-ray recording material may have a structure in which a liquid component containing a photochromic material is coated on a substrate of an arbitrary material and a recording layer is provided on the substrate. When the recording layer is provided on the substrate, for example, an appropriate amount of the above-described photochromic material is dispersed in a vehicle, and a uniform pressure film is formed on the substrate by a known thin film forming method such as a doctor blade method.

  Here, the material of the substrate on which the recording layer is formed is not particularly limited, and may be appropriately selected according to the use of the X-ray recording material, such as glass, resin, metal and the like.

  Thus, the X-ray recording material can also have a structure in which the recording layer is formed on the substrate.

  The X-ray recording medium to which the present invention is applied can be manufactured by the photochromic material and the X-ray recording medium manufacturing method described above.

  Examples of the present invention will be described below.

(1) Example 1
A sample of Example 1 was prepared using the photochromic material and manufacturing method described above. In Example 1, the powdery body with a composition of the photochromic material _{Ba (Mg 1-x-y} Fe x Al y) (Si 1-z Bz) O 4 as a raw material. The powdery body was molded into a circle and then fired in a reducing atmosphere. The baking process was performed for 2 hours in the temperature range of 1150 ° C to 1300 ° C. The fired product was in the form of a tablet having a flat and circular outer periphery, and the following confirmation was performed using this as an X-ray recording medium.

  (2) Device configuration for X-ray recording

  An apparatus configuration for obtaining an X-ray transmission image of an object is shown in FIG. As shown in FIG. 1A, the apparatus configuration 1 has an X-ray source 2, a slit 3, and an X-ray recording pellet 4 showing photochromic properties that is Example 1. As the X-ray source 2, a sealed tube X-ray generator using Cu as a target was used.

  An object to be irradiated with X-rays was placed at a position 5 on the front surface of the X-ray recording pellet 4. 1A shows an X-ray irradiation area 6 and an ultraviolet-visible spectroscopy measurement area 7 on the surface of the X-ray recording pellet 4.

  In the apparatus configuration 1, as shown in FIG. 1B, X-rays (symbol X) irradiated from the X-ray source 2 are irradiated to an object 8 for which an X-ray transmission image is desired. Part of the X-rays transmitted through the object 8 is absorbed inside the object 8, and X-rays having an intensity distribution are irradiated to the X-ray recording pellet 4. As a result, the X-ray recording pellet 4 is colored reddish purple by X-ray irradiation, and a transmission image 9 is obtained.

(3) X-ray irradiation and absorption spectrum after heating First, in the apparatus configuration 1 described above, the X-ray recording pellet 4 was irradiated with X-rays without arranging the object 8. X-ray irradiation was performed for 2 hours under conditions of an output of 40 kV and 20 mA. Further, the X-ray recording pellet 4 after X-ray irradiation was left in an electric furnace heated to 250 ° C. for 10 minutes. At this time, absorption spectra of the X-ray recording pellet 4 after X-ray irradiation and the heated X-ray recording pellet 4 were confirmed by a UV-VIS-NIR spectrophotometer. FIG. 2 shows an absorption spectrum.

  As shown in FIG. 2, the sample after X-ray irradiation had an absorption spectrum (reference numeral 10) having a peak at a wavelength of 520 nm, and it was confirmed that the sample was colored red-purple from the white state before coloring. Moreover, the sample after heating became an absorption spectrum (symbol 11) in which the peak at a wavelength of 520 nm disappeared, and it was confirmed that the reddish purple color was decolored to be the original white color. As described above, the sample of Example 1 was colored with X-rays and exhibited photochromism that was decolorized by heating. Moreover, it became clear that it can be used repeatedly by coloring and decoloring.

(4) Acquisition of X-ray transmission image Subsequently, in the apparatus configuration 1 described above, X-ray irradiation was performed using a commercially available USB flash drive (USB memory) as an object 8. X-ray irradiation was performed for 3 hours under conditions of an output of 40 kV and 30 mA. As a result, an X-ray transmission image reflecting the internal element structure of the USB flash drive could be confirmed. For reference, the USB flash drive and its X-ray irradiation area are shown in Reference FIG. 1, and the obtained X-ray transmission image is shown in Reference FIG.

(5) Confirmation of durability by repeated recording Under the same conditions as in (4) above, the process of decolorization by X-ray irradiation and heating was performed 200 times or more, and the presence or absence of deterioration of photochromism characteristics was examined. Specifically, the peak intensity at a wavelength of 520 nm was measured after X-ray irradiation and after heating. FIG. 3 shows the monitoring results of peak intensity. In FIG. 3, the horizontal axis represents the number of measurements, and the vertical axis represents the peak intensity at a wavelength of 520 nm.

  As shown in FIG. 3, the X-ray recording medium of Example 1 showed no decrease in the peak intensity at a wavelength of 520 nm even at the time of 20 measurements. Further, although not shown in FIG. 3, the peak intensity at the same level as the initial measurement was maintained even after the 200th measurement. That is, the X-ray recording medium of Example 1 has sufficient sensitivity to X-rays even when it is used repeatedly, and has durability capable of acquiring a reproducible X-ray transmission image. Became clear.

(6) X-ray output and irradiation time The X-ray recording medium of Example 1 was irradiated with X-rays having different outputs, and the absorbance at a wavelength of 520 nm was monitored at each irradiation time. The output of X-rays was set at three stages of 30 mA (reference numeral 12), 20 mA (reference numeral 13), and 10 mA (reference numeral 14) at 40 kV. FIG. 4 shows the results of monitoring absorbance at a wavelength of 520 nm. Further, the lower right of FIG. 4 shows a logarithmic display of the left graph of FIG.

  As is clear from FIG. 4, an increase in absorbance at a wavelength of 520 nm was observed at an irradiation time of 1500 seconds at each output. Moreover, in each output, it became a saturated state in which the absorbance at a wavelength of 520 nm hardly increased after an irradiation time of 3500 seconds. From this result, it was found that if the X-ray output is 40 kV and 10 mA or more, the coloration can be sufficiently confirmed if the X-ray irradiation is performed for about 25 minutes.

  Further, in relation to (6) described above, it is possible to detect a simple X-ray irradiation amount using an X-ray recording medium. Specifically, the X-ray irradiation dose can be easily quantified from the coloring amount by creating a calibration curve for the X-ray irradiation amount and the coloring amount of the X-ray recording medium. As described above, the X-ray recording medium of the present invention can be used not only for recording X-ray transmission images but also as a measuring method.

(7) Examples 2-8
Samples of Examples 2 to 8 shown in Table 1 below were produced using the photochromic material and the manufacturing method described above.

(8) Confirmation of influence of additive on coloring intensity and fading Example 2-5 were irradiated with ultraviolet light at a wavelength of 254 nm for 10 minutes and then left in the dark to monitor the absorbance at a wavelength of 520 nm. . In this measurement, the color strength of each Example and fading with time were confirmed. FIG. 5 is a graph showing the relationship between the measurement time and the absorbance at a wavelength of 520 nm in each example. FIG. 6 is a graph showing the results shown in FIG. 5 in common logarithm. Reference numeral 16 corresponds to the second embodiment (BMSFAB1), reference numeral 17 corresponds to the third embodiment (BMSFAB2), reference numeral 18 corresponds to the fourth embodiment (BMSB), and reference numeral 19 corresponds to the fifth embodiment (BMSAB).

  As shown in FIG. 5, Example 2 (BMSFAB1) and Example 3 (BMSFAB2) had a higher coloring intensity than Example 4 (BMSB) and Example 5 (BMSAB). From the comparison between Example 2 (BMSFAB1) and Example 3 (BMSFAB2) and Example 5 (BMSAB), it was revealed that the coloring strength was improved by the addition of Fe. Moreover, it became clear from the comparison of Example 4 (BMSB) and Example 5 (BMSAB) that coloring persistence improves by addition of Al.

  As shown in FIG. 6, from the results of Examples 2 to 5, regarding the color retention, the addition of Fe contributes to the improvement of the color retention in the initial period of color fading, and Al in the middle to long period of color fading. It became clear that the addition of added contributes to the improvement of color retention.

(9) Confirmation of absorption spectrum About the said Examples 2-8, the ultraviolet-ray of wavelength 254nm was irradiated, and the absorption spectrum of each Example was confirmed with the UV-VIS-NIR spectrophotometer. FIG. 7 shows an absorption spectrum. Reference numeral 21 is the second embodiment (BMSFAB1), reference numeral 20 is the third embodiment (BMSFAB2), reference numeral 22 is the fourth embodiment (BMSB), reference numeral 23 is the fifth embodiment (BMSAB), and reference numeral 24 is the sixth embodiment (BMSF). ), 25 corresponds to Example 7 (BMS), and 26 corresponds to Example 8 (BMSA).

  As shown in FIG. 7, at the wavelength of 520 nm, Example 2 (BMSFAB1) and Example 3 (BMSFAB2) had the highest peak, and the coloring intensity was large. Moreover, it became clear from the result of Examples 2-8 that the effect of addition with respect to coloring intensity | strength will influence in order of B, Fe, and Al addition> B addition> Fe addition> Al addition.

As described above, the X-ray recording material according to the present invention is reusable and durable, and has excellent practicality.
In addition, the method for producing an X-ray recording material according to the present invention is capable of producing an X-ray recording material that can be used repeatedly, has durability, and has excellent practicality.
The X-ray recording medium according to the present invention is reusable and durable, and has excellent practicality.
In addition, the method for producing an X-ray recording medium according to the present invention can produce an X-ray recording medium that can be used repeatedly, has durability, and is highly practical.
Furthermore, the method for measuring an X-ray irradiation amount according to the present invention provides a method for measuring an X-ray irradiation amount that can be used repeatedly, has durability, and has excellent practicality.

DESCRIPTION OF SYMBOLS 1 Apparatus configuration 2 X-ray source 3 Slit 4 X-ray recording pellet 5 Position 6 X-ray irradiation area 7 Measurement area of ultraviolet visible spectroscopy 8 Object 9 Transmission image 10 Absorption spectrum after X-ray irradiation 11 Absorption spectrum after heating 12 Sample irradiated with 40 kV, 30 mA X-ray 13 Sample irradiated with 40 kV, 20 mA X-ray 14 Sample irradiated with 40 kV, 10 mA X-ray 15 Graph showing the left graph of FIG. 4 in logarithm 16 Example 2 ( BMSFAB1)
17 Example 3 (BMSFAB2)
18 Example 4 (BMSB)
19 Example 5 (BMSAB)
20 Example 3 (BMSFAB2)
21 Example 2 (BMSFAB1)
22 Example 4 (BMSB)
23 Example 5 (BMSAB)
24 Example 6 (BMSF)
25 Example 7 (BMS)
26 Example 8 (BMSA)

Claims (8)

  An X-ray recording material containing a silicate compound exhibiting photochromic properties. The X-ray recording material according to claim 1, wherein the silicate compound contains at least barium and magnesium. 3. The X according to claim 2, wherein at least part of Si and Mg of the SiO ₄ —MgO ₄ network structure constituting the skeleton of the silicate compound is substituted with at least one element selected from Fe, B, or Al. Line recording material. A method for producing an X-ray recording material comprising a step of firing a powder containing a silicate compound exhibiting photochromic properties in a reducing atmosphere at 1150 ° C. to 1300 ° C. for 2 hours or more. An X-ray recording medium having a recording layer in which an X-ray recording material containing a silicate compound exhibiting photochromic properties is uniformly blended and rewritable. The X-ray recording medium according to claim 5, wherein the X-ray recording medium includes a scintillator that emits fluorescence when irradiated with X-rays and at least part of the wavelength range of the emission spectrum overlaps with the wavelength range of the absorbance spectrum exhibited by the silicate compound. . An X-ray recording material containing a silicate compound exhibiting photochromic properties, and is colored by irradiating an X-ray recording medium configured to be decolorable by heating with X-rays in the wavelength range of 0.001 to 10 nm. X Recording method using a linear recording medium. A coloring step of coloring an X-ray recording medium composed of an X-ray recording material containing a silicate compound exhibiting photochromic properties by irradiating X-rays in the wavelength range of 0.001 to 10 nm;
A detection step of detecting an X-ray irradiation amount from a coloring amount of the X-ray recording material obtained in the coloring step. A method for measuring an X-ray irradiation amount.