JPH0776318B2 - Colored aqueous ink composition for imprinting data on X-ray photograph - Google Patents

Description

TECHNICAL FIELD The present invention relates to a colored aqueous ink composition for imprinting data on an X-ray photograph, and more specifically, describes required data on, for example, paper, woven fabric, non-woven fabric, etc. However, the present invention relates to a colored water-based ink composition for transferring the data to an X-ray photograph when the X-ray photograph is taken by adhering this to an X-ray photograph film.

2. Description of the Related Art When taking an X-ray photograph of a human body or the like, usually, the date of photography, the name of the person to be photographed, the gender, and other required data are simultaneously imprinted on the film. For this purpose, conventionally, a method of manually arranging and sticking single letter type characters made of lead, which is hard to transmit X-rays, at one corner of the film cassette has been adopted. However, according to this method, the work of arranging the single character type is extremely complicated, and the amount of data for imprinting is naturally limited.

There is also known a device for data imprinting in which a lead foil as a writing surface is exposed and the lead foil is held between the films.
To use this instrument, writing on the lead foil, that is, the lead foil is scraped off, so writing is somewhat easy, but since the part covered with the lead foil unnecessarily blocks X-rays, an X-ray photograph There are many film parts that cannot be used for.

Therefore, for example, in Japanese Examined Patent Publication No. 62-27704, a paste-like coating agent prepared by mixing fine powders of lead compounds such as lead oxide, lead white, and lead sulfide with a quick-drying binder, for example, A method has been proposed in which required data is written on each of the folded paper pieces so as to be duplicated after photographing, and the data is attached to an X-ray photographic film. However, even with this method, in practice, it is not easy to describe the data so that it is exactly duplicated, and since the coating material is a paste containing fine powder of a lead compound, The fine powder is liable to settle, requires stirring immediately before use, or requires a special tool as a writing tool, and is inferior in writability. Furthermore, the coating composition is liable to dry during storage, is inferior in storability, is apt to catch fire, and is also inferior in safety.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention has been made to solve the above-mentioned problems in the conventional method of imprinting data on an X-ray photograph, is water-based, and has high safety, And, for example, with excellent writability and storability that allow easy and smooth writing even with a normal marking pen,
It is an object to provide a colored aqueous ink composition for imprinting data on a colored X-ray photograph.

Means for Solving Problems The colored water-based ink composition for imprinting data on an X-ray photograph according to the present invention contains an element (excluding a rare gas element) having an atomic number of 47 or more as a simple substance or a compound as an X-ray. Wavelength as a shielding agent
A dye having a sulfonate group in its molecule, which is dissolved in an aqueous solvent so that the mass absorption coefficient for X-ray of 0.1Å is 0.170 cm ² / g or more, and the sulfonate group is sodium sulfonate group At this time, a dye having a molecular weight of 250 or less per sodium sulfonate base is dissolved.

In general, the intensity I after an X-ray of intensity I ₀ has passed through a substance of thickness d (cm) is 1n (I ₀ / I) = μρd, where ρ (g / cm ³ ) is the density of the substance. (1) or I = I ₀ exp (−μρd) (2) holds, where ρμ (cm ⁻¹ ) is the linear absorption coefficient of the substance for X-rays, and μ (cm ² / g) is the substance Is defined as the mass absorption coefficient for X-rays. This mass absorption coefficient is a unique value that each element constituting the substance has when the wavelength of X-rays is determined, and it is known that compounds and mixtures have additivity. That is, when the mass absorption coefficient of each component element constituting the compound or mixture is μ _i , the weight ratio is w _i, and the density of the compound or mixture is ρ, the mass absorption coefficient μ of the compound or mixture is μ = Σμ _i w _i can be obtained.

The ink composition according to the present invention has a mass absorption coefficient for X-rays having a wavelength of 0.1 Å, using an element having an atomic number of 47 or more (excluding rare gas elements) or a compound as an X-ray shielding agent.
Dissolved in an aqueous solvent so that the concentration becomes 0.170 cm ² / g or more.

According to the experiments by the present inventors, in taking an X-ray photograph,
Lead foil with a thickness of 0.01 mm or more is effective for X-ray shielding. In the ink composition according to the present invention, the mass absorption coefficient for X-rays having a wavelength of 0.1Å is 0.170 cm ² / g or more,
The ink composition should have an X-ray shielding effect almost equivalent to that of a lead foil having a thickness of 0.01 mm or more, that is, a mass absorption coefficient for X-rays. However, the mass absorption coefficient of the ink composition means, in the present invention, X by a component other than the X-ray shielding agent.
The line shielding effect shall be ignored.

On the other hand, when the shielding power of X-rays is defined as μρd in the above formula (1), the X-ray shielding effect of the lead foil having a thickness d of 0.001 cm is as follows: mass absorption coefficient of lead μ: 3.41 cm ² / g Since it is 11.34 g / cm ³ , μρd is approximately 0.039.

Therefore, the density of the ink composition according to the present invention should be at least
If it is 1.1 g / cm ³ (actually, it is large in most cases), the absorptive writing surface, for example, when the ink composition is written on paper, the X-ray shielding power by the handwriting is 0.039. Therefore, the thickness t of the handwriting is t = 0.039 / (0.170 × 1.1) ≈2.1 (mm). The required handwriting thickness becomes smaller as the mass absorption coefficient of the ink composition becomes larger than 0.170 cm ² / g.
For example, when the mass absorption coefficient of the ink composition is 0.5 cm ² / g, the required handwriting thickness is about 0.7 mm. Such a required handwriting thickness can be easily obtained by selecting the viscosity and penetrability of the ink composition, the penetrability of the writing surface, and the like.

The following can be exemplified as the element that constitutes the simple substance or compound that can be preferably used in the present invention. However, the value in parentheses indicates the mass absorption coefficient (cm ² / g) of the element with respect to X-rays having a wavelength of 0.1Å.

Ag (1.05), Cd (1.10), In (1.15), Sn (1.20), Sb
(1.25), Te (1.30), I (1.36), Cs (1.48), Ba
(1.53), La (1.60), Ce (1.66), Pr (1.72), Nd
(1.80, Pm (1.86), Sm (1.93), Eu (2.02), Gd (2.
09), Tb (2.18), Tm (2.50), Lu (2.66), Hf (2.7
5), Ta (2.82), W (2.90), Re (2.96), Os (3.0
3), Ir (3.10), Pt (3.17), Au (3.23), Hg (3.3
0), Tl (3.36), Pb (3.41), Bi (3.45), Po (3.5
2), Er (2.42), Ra (3.70), Ac (3.75), Th (3.8
1), Pa (3.86) and U (3.91).

In the present invention, the X-ray shielding agent preferably has a solubility in water of about 10% by weight or more, and accordingly,
Examples of the above simple substance or compound that can be used as the X-ray shielding agent in the present invention include AgF, AgNO ₃ , CdI ₂ , Cd (N
_{O 3) 2 · 4H 2 O} , 3CdSO 4 · 4H 2 O, SnCl 2, NH 4 SnBr 4 · 4H
₂ O, NH ₄ SnCl ₃ , SbF ₃ , SbCl ₃ , K ₃ SbS ₄ / 5H ₂ O, (NH ₄ ) ₃ S
bS ₄ , LiSbS ₄・ 10H ₂ O, TeBr ₄ , H ₂ TeO ₄・ 2H ₂ O, K ₂ TeO ₄ , I
₂ , HI, LiI ・ 3H ₂ O, ZnI ₂ , CaI ₂ , NH ₄ I, NaI, KI, Li (I
_{O 3), MgI 2 · 8H} 2 O, ICN, Cs 2 CO 3, CsI, CsCl, CsOH, Cs
N ₃ , Cs ₂ SO ₄ , Cs ₂ MoO ₄ , Cs ₂ SeO ₄ , BaBr ₂ , Ba (CN) ₂ , B
a (ClO ₃ ) ₂ , H ₂ O, BaI ₂ , 2H ₂ O, BaCl ₂ , Ba (Cl
_{O 4) 2, La 2 (} SeO 4) 3, La (NO 3) 3 · 6H 2 O, La (Br
O ₃ ) ₃ , Mg ₃ La ₂ (NO ₃ ) ₁₂ , (NH ₄ ) ₂ La (NO ₃ ) ₅ , CeCl
_{3, Ce 2 (SO 4)} 3 · 12H 2 O, MgCe 2 (NO 3) 12, Mg 3 Pr 2 (NO
_{3) 12, Mn 3 Pr 2} (NO 3) 12, PrCl 3 · 7H 2 O, Pr (NO 3) 3,
Pr (BrO ₃ ) ₃ , Mg ₃ Nd ₂ (NO ₃ ) ₁₂ , Mn ₃ Nd ₂ (NO ₃ ) ₁₂ , Nd
_{2 (SeO 4) 3, KNd} (SeO 4) 2 · 4H 2 O, SmCl 3, Sm (Br
O ₃ ) ₃ , Tb (BrO ₃ ) ₃ , (NH ₄ ) ₂ HfF ₆ , TaF ₅ , Na ₂ WO ₄ ,
K ₂ WO ₄ , Cs ₂ WO ₄ , (NH ₄ ) ₂ WO ₄ , Cs ₂ (WO ₄ ), NH ₄ ReO ₃ S,
MgPt (CN) ₄ , PtCl ₄ / 5H ₂ O, K ₂ Pt (CN) ₄ , AuCl ₃ , Na
AuCl ₄・ 2H ₂ O, KAuCl ₄ , LiAuCl ₄ , Hg (CN) ₂ , Hg ₂ (ClO
₄ ) ₂ , HgNO ₃ · H ₂ O, TlCl ₃ · 4H ₂ O, TlH ₂ PO ₃ , TlNO ₃ , Tl
_{OH, PbCl, Pb (ClO 3} ) 2 · H 2 O, Pb (NO 3) 2, Pb (Cl
_{O 4) 2 · 3H 2 O} , PbSiF 6, InBr 3 · 5H 2 O, InI 3, InCl 3 · 4H
_{2 O, RaBr 2, RaCl 2} , VO 2 Cl 2 · 3H 2 O, VO 2 (NO 3) 2 · 6H
_{2 O, Er 2 (SO 4} ) 3 · 8H 2 O, Gd (BrO 3) 3 · 9H 2 O, NH 4 ReO
₃ S etc. can be mentioned.

As described above, the simple substance or the compound is an aqueous solvent in the ink composition according to the present invention so that the mass absorption coefficient for X-rays having a wavelength of 0.1Å of the ink composition is 0.170 cm ² / g or more. Although dissolved, it is usually contained in the ink composition in an amount of 10% by weight or more. Preferably, the X-ray shielding agent has a wavelength of 0.1 in the ink composition.
It is melted so that the mass absorption coefficient for X-ray of Å becomes 0.5 cm ² / g or more. Therefore, the upper limit of the amount of the X-ray shielding agent blended is not particularly limited to the saturated dissolution amount, but is usually 60% by weight or less. The above simple substance or compound is blended in the ink composition alone or as a mixture of two or more kinds.

In the ink composition according to the present invention, water is used as the main solvent, and in addition to water, the solubility of each component of the ink composition is adjusted, or the ink composition is applied to penetrate into a liquid-absorptive writing surface. As a co-solvent and / or a humectant for adjusting the properties or suppressing the evaporation rate of water, lower aliphatic alcohols such as methanol, ethanol, isopropanol, funnel oil, glycerin, ethylene glycol, propylene glycol, butanediol, Xylene glycol,
Glycols such as diethylene glycol, cellosolve,
Water-miscible organic solvents such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, butyl carbitol, glycol monoethers such as propylene glycol monomethyl ether are used. Water as a main solvent is usually contained in the ink composition in the range of 10 to 80% by weight, though it depends on the X-ray shielding agent used. The organic solvent is usually contained in the range of 1 to 50% by weight.

In the present invention, among the above X-ray shielding agents, in particular, an alkali metal tungstate or ammonium tungstate represented by the general formula M ₂ WO ₄ (wherein M represents an alkali metal or ammonium) is used. It is preferably used. As a preferable specific example of such a tungstate, for example, Na ₂ W
O ₄ , K ₂ WO ₄ and Cs ₂ WO ₄ can be mentioned. These may be used alone or as a mixture, and may also be used as a mixture with other simple substance or compound as described above.

In particular, the alkali metal tungstate and ammonium tungstate described above are significantly less toxic than other heavy metal salts and have a large mass absorption coefficient for X-ray of 0.1Å. For example, BaI ₂ · 2H ₂ O has a mass absorption coefficient of 1.31 cm ² / g for X-rays of 0.1 Å, but that of Na ₂ WO ₄ 2H ₂ O is 1.68 cm ² / g, K ₂ WO ₄ It's 1.
72cm ² / g, that of Cs ₂ WO ₄ is 1.82cm ² / g.

In such an ink composition, the alkali metal tungstate is preferably 15 wt% to a saturated dissolution amount or less,
Particularly preferably, the content is dissolved and contained in the range of 20 to 60% by weight.

Further, the preferred ink composition according to the present invention contains an alkali metal base and / or an alkali metal iodide together with the alkali metal tungstate. Ammonia can be used instead of the alkali metal base.
These alkali metal bases, ammonia or alkali metal iodides enhance the solubility of the tungstate in an aqueous solvent or enhance the solubility stability, and are therefore used as a solubilizing agent for the X-ray shielding agent.

The alkali metal base is preferably a strong alkaline substance, and hydroxides such as sodium hydroxide, potassium hydroxide, cesium hydroxide and lithium hydroxide are particularly preferably used. However, carbonates and hydrogen carbonates such as sodium carbonate, sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, and cesium carbonate are also used. The amount of these alkali metal bases or ammonia in the ink composition may be an amount sufficient to make the ink composition alkaline, and therefore, depending on the alkali used, usually, in the ink composition, 0.01 to 2.0. %, Preferably 0.05 to 0.5% by weight. However, when cesium carbonate is used, the cesium carbonate itself is X
Since it functions as a line shielding agent, in the ink composition,
It is used in the range of 40% by weight or less, preferably 30% by weight or less.

As the alkali metal iodide, for example, sodium iodide, potassium iodide, cesium iodide and the like are preferably used. The amount of these alkali metal iodides in the ink composition may be equal to or less than the saturated dissolution amount,
Usually, it is in the range of 40% by weight or less, preferably 30% by weight or less.

In the present invention, in addition to the tungstate, in particular, AgNO ₃ , ZnI ₂ , BaI ₂ · 2H ₂ O, SbCl ₃ , HgNO ₃ · H.
₂ O, PbCl, KI, NaI, CsI, CsCO ₃ , CsOH and the like are preferably used.

When barium iodide or zinc iodide is contained as an X-ray shielding agent, in order to stabilize the solubility of these in water, the amount of 0.01% by weight or less of hydrochloric acid or the like in the ink composition is used. It is preferable to coexist with an inorganic acid or an organic acid such as acetic acid.

In the ink composition according to the present invention, when barium iodide, zinc iodide, or the like is used as the X-ray shielding agent, iodine is partly liberated to color the ink composition.
The ink composition can also be colored by adding iodine to an iodine salt such as potassium iodide or sodium iodide. Furthermore, as an X-ray shielding agent,
When iodine or an iodine compound is used, starch can be added as a color former.

However, the coloring of the ink composition with iodine itself tends to fade or become colorless over time, and is therefore not always preferable as a coloring agent.
On the other hand, when the above-mentioned tungstate is used as an X-ray shielding agent, iodine does not dissolve in a concentrated aqueous solution of tungstate. In addition, for example, even if iodine salt such as sodium iodide and iodine are added to a concentrated aqueous solution of tungstate, the coloring occurs temporarily, but with the passage of time, the coloring due to iodine disappears, and finally, complete coloring occurs. Becomes colorless.

Therefore, according to the present invention, a dye having a sulfonate group in the molecule as a colorant, wherein when the sulfonate group is a sodium sulfonate group, the molecular weight per sodium sulfonate group is 250 or less. A dye is used. Such dyes unexpectedly produce high concentrations of X
It dissolves relatively well in an ink composition containing a line-blocking agent to give a uniformly colored ink composition. The ink composition according to the present invention contains the above-mentioned X-ray shielding agent in a high concentration in a dissolved state, but such a dye can uniformly color the ink composition in an amount that does not cause salting out. .

In the present invention, as the dye having a sulfonate group, for example, those having an alkali metal salt such as lithium, sodium and potassium in the molecule, an amine salt such as an ethanolamine salt, and a sulfonate group as an ammonium salt are preferable. Used.

Examples of such dyes include Acid Yellow 9, Foot Yellow 3, Acid Orange 10, and Acid Yellow.
Red 1, Acid Red 18, Acid Red 26,
Acid Red 27, Acid Red 35, Direct Yellow 11, Direct Yellow 50, Direct
Red 80, Direct Blue 25, Direct Blue
71, direct black 74, direct black 7
Examples thereof include 5,4-sulfonated nigrosine and pyranine.

Further, in the present invention, as a colorant, a compound represented by the general formula (In the formula, SO ₃ M represents an alkali metal base, amino base, or ammonium base of sulfonic acid, and R ¹ and R ² may be the same or different, H acid residue, K acid residue, and J acid residue. Group, G
Acid residue, general formula (SO ₃ M is the same as above.), Or (SO ₃ M is the same as above, R ³ represents a hydroxyl group or an amino group, and R ⁴ represents hydrogen, an alkyl group, a hydroxyl group, an amino group, a halogen or an alkoxy group.)) Is also preferably used. To be

In the above formula, when M is an alkali metal, preferably M is potassium or sodium, and when R ⁴ is an alkyl group, a halogen or an alkoxy group, it is preferably a methyl group, chlorine or methoxy group, respectively.

In the ink composition according to the present invention, since inorganic salts are dissolved in a high concentration, some dyes are salted out in an aqueous solution, but the above dyes are not salted out, and a comparatively large amount is obtained. It can be dissolved in the ink composition.

Such a dye is usually contained in an ink composition in an amount of 0.001 to
It is dissolved in 2.0% by weight, preferably 0.001 to 1.0% by weight. When the amount is too small, it is insufficient for coloring the ink composition. On the other hand, when the amount is too large, as described above, salting out and salting out,
The X-ray shielding agent may be taken in and precipitated, or may form a salt with an active ingredient of the X-ray shielding agent and precipitate, which is not preferable.

The above dye is used as a solvent, in particular, an aliphatic lower alcohol having 4 or less carbon atoms such as methanol, ethanol and isopropanol, ethylene glycol, propylene glycol, butanediol, xylene glycol, glycerin, trimethylolpropane, 3-methylpentane-1. ,
C2-C9 aliphatic dihydric or trihydric alcohol such as 3,5-triol, ethylene glycol monomethyl ether, 3-methyl-3-methoxybutanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, Methyl carbitol, ethyl carbitol,
It is desirable to use it together with 0.1 to 20% by weight, preferably 0.5 to 10% by weight, of one or a mixture of two or more types of alcohol ether having 3 to 9 carbon atoms such as butyl carbitol.

The ink composition according to the present invention may further contain additives such as a surfactant, a rust preventive and a preservative in addition to the above-mentioned components. Examples of the surfactant include anionic surfactants such as sodium dialkylsulfosuccinate, sodium alkylbenzenesulfonate, and lead naphthenate, or polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, and the like. Nonionic surfactants are preferably used. In addition, 2,4,7,9-tetramethyl-5
Acetylene glycols such as -decyne-4,7-diol and ethylene oxide adducts thereof are also preferably used.

Further, as the rust preventive, for example, 1,3,5-benzotriazole, as the preservative, for example, tetrabutyl tin,
Sodium benzoate or the like can be used.

The ink composition according to the present invention can be easily produced by dissolving each of the above components in water. However, the required components may be produced in the solvent by chemical reaction in the aqueous solvent. For example, by reacting barium hydroxide with hydrogen iodide in an aqueous solvent, barium iodide is produced, and an ink composition using this as an X-ray shielding agent can be obtained.

Although the alkyl metal tungstate as described above may be dissolved in water itself, for example, by dissolving sodium carbonate or potassium carbonate and cesium tungstate in water, tungsten is formed in situ. You may generate sodium acid salt and potassium tungstate.

When the ink composition according to the present invention contains a solubilizing agent for the X-ray shielding agent as described above, such an ink composition is preferably prepared by first dissolving the solubilizing agent in water and then by X-ray. It is prepared by dissolving the masking agent and then the dye and other additives.

When the ink composition according to the present invention contains an iodide such as barium iodide, zinc iodide, or calcium iodide as an X-ray shielding agent, the ink composition after being adjusted is In some cases, carbon dioxide gas is absorbed and reacts with an iodine compound to release hydrogen iodide and to produce a water-insoluble carbonate salt. However, such an ink composition can also be used if there is no particular problem in writing. Of course, an insoluble carbonate may be filtered out to obtain an ink composition.

As described above, the ink composition according to the present invention may contain a water-insoluble compound by-produced in some cases, but in most cases, it is a colored aqueous solution and has a wavelength of 0.1Å.
Since its mass absorption coefficient for X-rays was 0.170 cm ² / g or more, write the required data on a sheet with liquid absorbability and attach it to a dry plate containing an X-ray photographic film. Therefore, this data can be imprinted on the film simultaneously with the X-ray photography.

Moreover, since the ink composition according to the present invention is colored, when the required data is written on a sheet having a liquid-absorbing property, the density of the handwriting is set to a predetermined value or more, so that the ink on the film is It is possible to surely increase the imprint density.

Furthermore, since the ink composition according to the present invention is substantially an aqueous solution, it can be used for writing by using a conventional ordinary writing instrument. Examples of such writing instruments include marking pens, felt-tip pens, water-based ballpoint pens, brush pens, and fountain pens.

Examples of the liquid-absorbent sheet include paper, woven cloth, non-woven cloth, foam and the like. In this way, by using a liquid-absorbent sheet as the writing surface, it is easy to dry the ink, and an ink layer is formed over the thickness of the sheet to imprint the written data. You can be sure.

However, it is not preferable to use, as the writing surface, a sheet made of glass, resin, metal, or the like that is not liquid-absorbent as described above, because the imprinting of data becomes uncertain.

EFFECTS OF THE INVENTION As described above, the ink composition for imprinting data on an X-ray photograph according to the present invention can be easily and smoothly written with, for example, an ordinary marking pen, and is water-based. It is colored, highly safe, and has excellent storage stability. For example, write the required data on paper, woven fabric, non-woven fabric, etc. and attach it to an X-ray film. For example, at the same time when an X-ray photograph is taken, the data can be surely transferred to the X-ray photograph.

Example A water-based ink composition having the composition shown below was prepared. The blending amount is indicated by the number of parts by weight.

Ink composition 1 AgNO ₃ 50 parts Water 45 parts Glycerin 4.5 parts Ink bio-lett 306 ¹⁾ 0.5 parts Mass absorption coefficient 0.359 cm ² / g Ink composition ² CsCO ₃ 60 parts Water 39.98 parts Pyranine ²⁾ 0.02 parts Mass absorption coefficient 0.740 cm ² / g ink composition 3 KI 46 parts NaI 4 parts water 49.97 parts Sansetsuto yellow FCF ³⁾ 0.03 parts by mass absorption coefficient 0.617cm ² / g ink composition _{4 Na 2 WO 4 · 2H 2} O 25 parts KI 25 parts water 45 parts ethylene glycol 4 parts nigrosine R455 ⁴⁾ 49.97 parts by mass absorption coefficient 0.730cm ² / g ink composition 5 BaI ₂ · 2H ₂ O 65 parts water 30 parts concentrated hydrochloric acid 0.002 parts propylene glycol 4.988 parts Niyukokushin ⁵⁾ 0.01 parts by weight Absorption coefficient 0.858 cm ² / g Ink composition 6 SbCl ₃ 42 parts Water 53 parts Isopropanol 4.88 parts Nippon New Blue 5BS ⁶⁾ 0.02 parts Surfinol 61 ⁷⁾ 0.1 parts Mass absorption coefficient 0.314 cm ² / g Ink composition 7 NaI 50 parts KI 3 parts Water 46.9 parts Ota Yellow No.6 ⁸⁾ 0.1 parts by mass absorption coefficient 0.622cm ² / g ink composition 8 AgNO ₃ 45 parts 50 parts Water Glycerin 4.98 parts pyranine 0.02 parts by mass absorption coefficient 0.359cm ² / g ink composition 9 KI 46 parts NaI 4 parts Water 49.8 parts Nigrosine R455 0.2 parts Mass absorption coefficient 0.617cm ² / g Ink composition 10 Cs ₂ WO ₄ 60 parts KOH 0.1 parts Water 35 parts Ethylene glycol 4.895 parts Edible red 106 ⁹⁾ 0.005 parts Mass absorption coefficient 1.072 cm ² / g Ink composition 11 Na ₂ WO ₄・ 2H ₂ O 30 parts KI 25 parts Water 40 parts Hexylene glycol 4.96 parts Direct Fast Yellow Special ¹⁰⁾ 0.04
Part mass absorption coefficient 0.814cm ² / g ink composition 12 BaI ₂ · 2H ₂ O 65 parts Water 30 parts concentrated hydrochloric acid 0.01 parts Diethylene glycol monomethyl ether 4.95 parts water Yellow No.6 0.04 parts by mass absorption coefficient 0.858cm ² / g ink Composition 13 KI 48 parts Water 51.8 parts Eosin ¹¹⁾ 0.2 parts Mass absorption coefficient 0.595 cm ² / g Ink composition 14 Cs ₂ WO ₄ 55 parts CsI 7 parts KOH 0.2 parts Water 32.77 parts Ethylene glycol 5 parts Pyranine 0.03 parts Mass absorption For ink compositions having a coefficient of 1.100 cm ² / g or more, write characters on a piece of paper,
When this was attached to a dry plate containing an X-ray photo film and an X-ray photograph was taken, the characters were clearly imprinted on the film.

3) Hodogaya Chemical Co., Ltd. CI Hood Yellow 3 4) Orient Chemical Co., Ltd. CI Acid Black 2 5) Hodogaya Chemical Co., Ltd. CI Acid Red 18 6) Sumitomo Chemical Co., Ltd. ) CI Direct Blue 25 7) Nisshin Chemical Industry Co., Ltd. acetylene alcohol surfactant 9) CI Assisted Red 52 manufactured by Hodogaya Chemical Co., Ltd. 10) CI Direct Yes manufactured by Mitsubishi Kasei 11) CI Assisted Red 87 manufactured by Hodogaya Chemical Co., Ltd.

Claims (1)

[Claims] 1. A simple substance or compound of an element having an atomic number of 47 or more (excluding rare gas elements) as an X-ray shielding agent having a wavelength of 0.
A dye that has a sulfonate group in the molecule while being dissolved in an aqueous solvent so that the mass absorption coefficient for 1 Å X-ray is 0.170 cm ² / g or more, and the sulfonate group is sodium sulfonate group A colored aqueous ink composition for imprinting data on an X-ray photograph, which comprises a dye having a molecular weight of 250 or less per sodium sulfonate group dissolved therein.