JP4621591B2 - Nigrosine dye and method for producing the same - Google Patents

Description

  The present invention relates to a non-pyrophoric nigrosine dye and a method for producing the same.

In 1867, Cupier obtained nigrosine by reacting aniline with nitrobenzene in the presence of hydrochloric acid and iron (Fe) or iron chloride (FeCl ₂ ). Since then, various improvements have been made based on this method (Patent Documents 1 to 5).

  Despite such improvements in the synthesis method, the obtained nigrosine dye has a risk of spontaneous ignition, that is, spontaneous ignition occurs during storage or transportation.

Patent Document 6 (Patent Document 7) discloses a technique in which a pyrophoric nigrosine base is brought into contact with a gas containing oxygen in aniline as a method for suppressing the spontaneous ignition. However, it has been found that the nigrosine dye obtained by the method disclosed in Patent Document 6 (Patent Document 7) is completely insufficient for conversion to non-pyrophoric property.
US Pat. No. 1,896,244 US Patent No. 1988499 U.S. Pat. No. 4,056,530 German Patent No. 44406 German Patent No. 890104 U.S. Pat. No. 4,359,577 JP-A-56-141354

  The present invention has been made in view of the above problems existing in the prior art, and an object thereof is to provide a non-pyrophoric nigrosine dye and a method for producing the same.

  As a result of intensive studies to obtain non-pyrophoric nigrosine, the present inventors have found that there is a clear relationship between the amount of aniline in nigrosine measured by gas chromatography and the spontaneous ignition.

  Nigrosine usually contains aniline as a contaminant. The inventors pay attention to the relationship between the temperature of the sample introduction part of the gas chromatograph and the measured aniline content when the amount of aniline in nigrosine is quantified by gas chromatography (hereinafter also referred to as “GC method”). did. When the sample introduction part temperature is below a specific temperature, there is no substantial change between the sample introduction part temperature and the quantitative value of the aniline content in nigrosine, and aniline existing as a contaminant (hereinafter, “contamination aniline”). ")" Is almost quantified as it is.

  However, when the sample introduction part temperature exceeds the specific temperature, the quantitative value of the aniline content in nigrosine gradually increases as the temperature increases. This is considered to be due to the generation of aniline that is liberated by decomposition of a part of the nigrosine structure (hereinafter referred to as “free aniline”). The amount of this free aniline is high / low in the pyrophoric nature of nigrosine. / Perceived to be related to low. If the sample introduction part temperature is set to an appropriate temperature at which a sufficient amount of free aniline is generated, which is higher than the specific temperature, and the amount of impurities aniline is subtracted from the measured aniline amount, the amount of free aniline / Small is calculated.

  The aniline content (corresponding to the content of impurities aniline) measured by a gas chromatograph apparatus equipped with a glass sample introduction part at a sample introduction part temperature of 200 ° C. was A wt%, and the sample introduction part temperature was 260 ° C. As the B-A value (corresponding to the content of free aniline) becomes smaller when the aniline content (corresponding to the total content of impurities aniline and free aniline) is B wt%, , And a nigrosine dye having B-A ≦ 0.04% by weight becomes non-pyrophoric. There are no conventional nigrosine dyes with B-A ≦ 0.04% by weight.

  That is, the nigrosine dye of the present invention was measured with a gas chromatograph apparatus equipped with a glass sample introduction part, with the aniline content measured at 200 ° C. and the sample introduction part temperature at 260 ° C. When the aniline content is B wt%, B−A ≦ 0.04 wt%.

  The determination of pyrophoric properties in nigrosine dyes can be made according to predetermined UN recommendations. The nigrosine dye of the present invention is produced by the United Nations Recommendation “Recommendations on the Transport of Dangerous Goods—Tests and Standards Manual—Revised 3rd Edition (Test Method for Class 4, Self-heating Substances” [Recommendations on the TRANSPORT OF DANGEROUSGOODS- According to Manual of Tests and Criteria-Third revised edition (Class 4, Test method for self-heating substrates)] None of the heat generation at 200 ° C. or higher occurs.

  As a result of intensive studies on the cause and spontaneous ignition of the free aniline as described above in the conventional nigrosine dye, the present inventors have found that the generation of free aniline is due to partial decomposition of the nigrosine component, and a part of the nigrosine component. The accumulation of heat generated by the solution was presumed to be one cause of ignition. The method for producing a nigrosine dye of the present invention is intended to produce a nigrosine dye capable of reducing the amount of free aniline due to partial decomposition of the nigrosine component.

  That is, the method for producing a nigrosine dye of the present invention is a method for producing the nigrosine dye of the present invention, wherein the neutralized nigrosine base is heated.

  Since the nigrosine dye of the present invention is non-pyrophoric, it is highly safe and easy to handle in storage, transportation and the like. Moreover, according to the manufacturing method of the nigrosine dye of this invention, the non-pyrophoric nigrosine dye of this invention can be easily obtained from the conventional pyrophoric nigrosine dye.

  A more specific method for measuring the amount of aniline for specifying the nigrosine dye of the present invention is not particularly limited, and when the aniline contained in the nigrosine dye has a glass sample introduction part temperature of 200 ° C. and 260 ° C. In any case, it is only necessary to be able to quantify with good reproducibility. As an example, a method of measuring A weight% and B weight% (an aniline content measured by a gas chromatograph apparatus with glass sample introduction part temperatures of 200 ° C. and 260 ° C., respectively) in Examples and Comparative Examples described later is used. I will give you.

  To 0.1 g of a precisely weighed sample, 9 ml of a mixed solvent of ethanol: chloroform = 1: 1 and an internal standard solution (0.1 g of precisely weighed p-nitrotoluene, ethanol: chloroform = 1: 1 [volume ratio]) 1 ml of a solution dissolved in a solvent and adjusted to a total volume of 100 ml) and subjected to ultrasonic treatment for 20 minutes, 1 μl (microliter) of a filtrate filtered through a filter having a pore size of 0.45 μm, and the following gas chromatograph The amount of aniline in the sample is quantified by injecting it into the glass sample introduction part of the graph apparatus.

The gas chromatograph apparatus is as follows.
Gas chromatography: HP5890 (manufactured by Hewlett-Packard Company)
Column: DB-1701 (30 m × 0.53 mm ID × 1.0 μm Film) J & W oven: 100 ° C.-260 ° C. (10 ° C./min)
Injection port: glass, 200 ° C. or 260 ° C., split ratio 10: 1
Detector: Hydrogen ionization detector (FID), 280 ° C
Injection volume: 1 μl

  Other columns such as DB-5 (manufactured by J & W) may be used.

  The above test for determining the pyrophoric properties of nigrosine dyes, namely according to the UN recommendation “Recommendations on the TRANSPORT OF DANGEROOUSGOODS- Manual of tests-Criteria-Thirdfested Specifically, the test for storing in a cubic container having a side of 10 cm and maintaining a temperature of 140 ° C. can be performed as follows. In the examples and comparative examples described later, the spontaneous ignition was determined by the following spontaneous ignition test.

  The sample container is filled with a sample container made of a stainless steel net with a mesh opening of 0.053 mm and one side of which is a 10 cm cube, and the upper part is open, and the sample container is filled with the sample container. Is stored in a sample container cover that is made of a stainless steel net with an opening of 0.595 mm and is suspended in the center of the thermostatic chamber. It is made of a stainless steel net with a mesh opening of 0.595 mm and has a size of 15 cm in length, 15 cm in width, and 25 cm in height. In addition, a thermometer (thermocouple) is installed so that the temperature in the center of the sample and the temperature chamber can be measured. The temperature inside the thermostat is set to 140 ° C., and this temperature is maintained for 24 hours, and the temperature of the sample is continuously measured and recorded for 24 hours. If ignition is observed within 24 hours or the temperature of the sample exceeds 200 ° C., the test is stopped at that point. The time from the start of the test until the ignition is recognized or the temperature of the sample reaches 200 ° C. is the time until the ignition.

The nigrosine dye of the present invention can be produced, for example, by subjecting a pyrophoric nigrosine dye to heat treatment in a solvent. More specific examples include the following production methods.
(1) Heat treatment of pyrophoric nigrosine dye in the presence of organic acid

  The nigrosine dye of the present invention can be obtained by heat-treating a pyrophoric nigrosine dye in a solvent using an organic acid as a catalyst.

  The organic acid is preferably an organic acid having a pKa of 0 or more, and more preferably an organic acid having a pKa of 3 to 5. Particularly preferred are aliphatic or aromatic carboxylic acids represented by the formula (1).

［式（１）中、Ｒは脂肪族基又は芳香族基である。］

[In Formula (1), R is an aliphatic group or an aromatic group. ]

Specific examples of such carboxylic acids include aliphatic carboxylic acids such as formic acid, succinic acid, acetic acid, propionic acid, and butyric acid; aromatic carboxylic acids such as benzoic acid, phthalic acids, benzenetricarboxylic acids, and benzenetetracarboxylic acids. be able to.
With relatively strong acids (PKa <0) such as organic sulfonic acids among inorganic acids and organic acids such as hydrochloric acid and sulfuric acid, it is generally possible to obtain non-pyrophoric nigrosine dyes with BA ≦ 0.04%. difficult.

  When an organic acid is used as the catalyst, the temperature for the heat treatment is preferably 100 ° C. or higher and 250 ° C. or lower. More preferably, it is 160 degreeC or more and 220 degrees C or less.

  The heat treatment time varies depending on nigrosine used as a raw material, but is generally 5 to 48 hours. If the processing time is extremely short, sufficient effects may not be obtained.

(2) Heat treatment of pyrophoric nigrosine dye in the presence of a metal oxide or heteropoly acid By subjecting pyrophoric nigrosine dye to heat treatment using a metal oxide or heteropoly acid as a catalyst in a solvent, The inventive nigrosine dye can be obtained.

  The metal oxide may be one or more selected from silica, alumina, silica alumina, titania, molybdenum oxide (VI), tungsten oxide (VI), and vanadium oxide (V).

Also, the _{heteropolyacid, H 3 PMo 6 W 6 O} 40, H 3 PW 12 O 40, H 3 PMo 12 O 40, H 3 PMo 10 W 2 O 40, H 3 PMo 10 V 2 O 40, H 4 SiW ₁₂ O _40, and _H 4 can be _Gemo 12 1 or 2 or more selected from _{O 40.}

  When using a metal oxide or heteropolyacid as a catalyst, the temperature of the heat treatment is preferably 50 ° C. or higher and 250 ° C. or lower. More preferably, it is 100 degreeC or more and 220 degrees C or less.

  The heat treatment time varies depending on nigrosine used as a raw material, but is generally 5 to 48 hours. If the processing time is extremely short, sufficient effects may not be obtained.

(3) Non-catalytic heat treatment of pyrophoric nigrosine dye The nigrosine dye of the present invention can also be obtained by heat-treating a pyrophoric nigrosine dye in a solvent without a catalyst.

  The heating temperature in the case of no catalyst is preferably 200 ° C. or higher and 300 ° C. or lower. More preferably, it is 220 degreeC or more and 250 degrees C or less.

  The heat treatment time varies depending on nigrosine used as a raw material, but is generally 10 to 60 hours. If the processing time is extremely short, sufficient effects may not be obtained.

  The pyrophoric nigrosine dye (nigrosine) used as a starting material in the above production method may be produced by any method, but a neutralized nigrosine base (for example, CI solvent Black 5, CI Solvent Black 7 and derivatives thereof are desirable. More preferably, C.I. I. Solvent Black 7. A pyrophoric nigrosine dye (nigrosine) is contained in a cubic container with a side of 10 cm and maintained at a temperature of 140 ° C in accordance with the above-mentioned UN recommendations. Anything that occurs.

  Any of the above-mentioned production methods can be carried out in the absence of a solvent, but it is preferable to use a solvent from the viewpoint of convenience of the post-treatment process.

  As the solvent, various solvents such as alcohol solvents, aromatic solvents, aprotic polar solvents, amine solvents and the like can be used, among which aromatic amines are suitable.

  Examples of such aromatic amines include aniline, methylaniline, dimethylaniline, ethylaniline, diethylaniline, o-toluidine, m-toluidine, p-toluidine, benzylamine, dibenzylamine, tribenzylamine, diphenylamine. , Triphenylamine, α-naphthylamine, β-naphthylamine and the like. Of these, anilines having various substituents or unsubstituted are preferred, and aniline is most preferred.

  Moreover, the said manufacturing method can also perform heat processing under pressure.

  In any of the above production methods, depending on the solvent used, the treatment temperature can be increased using an autoclave.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, the content of this invention is not limited to these Examples. In the following description, “%” means “% by weight”.

Example 1
10 g of acetic acid (pKa = 4.56) is added to a mixture of 1.0 kg of pyrophoric nigrosine (BA = 0.11%) and 2.0 kg of aniline, which is a commercially available neutralized nigrosine base. In addition, the mixture was refluxed in the atmosphere for 20 hours with stirring (the solution temperature at this time was about 190 ° C.). Thereafter, the mixture was allowed to cool to about 30 ° C., then washed twice with 1 L (liter) of 2% NaOH aqueous solution and further washed with water.

  GC analysis of the obtained nigrosine dye after drying under reduced pressure revealed that the aniline amount A was 0.21% when the sample introduction part temperature was 200 ° C., and the aniline amount B was 0.24% when the sample introduction part temperature was 260 ° C. That is, B−A = 0.03%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 2
When the treatment was conducted in the same manner as in Example 1 except that the reflux treatment time was 30 hours, the aniline content A in the obtained nigrosine dye at a sample introduction part temperature of 200 ° C. was 0.21%, and the sample introduction part temperature 260. The amount B of aniline at 0.2 ° C. was 0.22%, that is, B−A = 0.01%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 3
The same treatment as in Example 1 was conducted except that 20 g of propionic acid (pKa = 4.67) was used in place of acetic acid. As a result, the amount of aniline A at the sample introduction part temperature of 200 ° C. in the obtained nigrosine dye was 0. When the sample introduction part temperature was 260 ° C., the aniline amount B was 0.20%, that is, B−A = 0.02%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 4
When the same treatment as in Example 1 was performed except that 20 g of benzoic acid (pKa = 4.00) was used instead of acetic acid, the amount of aniline A at the sample introduction part temperature of 200 ° C. in the obtained nigrosine dye was 0. When the sample introduction part temperature was 260 ° C., the aniline amount B was 0.18%, that is, B−A = 0.03%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 5
In place of acetic acid, 40 g of silica gel for column chromatography (manufactured by Wako Pure Chemical Industries, Ltd.) was used, and after refluxing, the same treatment as in Example 1 was carried out except that the silica gel was removed by filtration. The aniline amount A was 0.52% when the part temperature was 200 ° C., and the aniline amount B was 0.54% when the sample introduction part temperature was 260 ° C., that is, B−A = 0.02%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 6
When the treatment was conducted in the same manner as in Example 5 except that the reflux treatment time was 24 hours, the amount of aniline A in the obtained nigrosine dye when the sample introduction part temperature was 200 ° C. was 0.63%, and the sample introduction part temperature 260 The aniline content B at 0 ° C. was 0.64%, that is, B−A = 0.01%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 7
When the same treatment as in Example 5 was performed except that 40 g of molecular sieves 4A (Aldrich: silica alumina) was used instead of silica gel, the amount of aniline in the obtained nigrosine dye when the sample introduction part temperature was 200 ° C. A When the sample introduction part temperature was 260 ° C., the aniline amount B was 0.33%, that is, B−A = 0.02%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 8
When the same treatment as in Example 6 was performed except that 30 g of H ₃ PMo ₆ W ₆ O ₄₀ was used instead of silica gel, the amount of aniline A at a sample introduction part temperature of 200 ° C. in the obtained nigrosine dye was 0.00. The amount of aniline B was 11% when the sample introduction part temperature was 260 ° C. and was 0.12%, that is, B−A = 0.01%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 9
When the same treatment was conducted as in Example 5 except that 40 g of H ₃ PMo ₁₀ V ₂ O ₄₀ was used instead of silica gel, the amount of aniline A at the sample introduction part temperature of 200 ° C. in the obtained nigrosine dye was 0.11. %, And the sample introduction part temperature 260 ° C., the aniline amount B was 0.13%, that is, B−A = 0.02%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Example 10
A mixture of 1.0 kg of pyrophoric nigrosine (BA = 0.11%) and 1.0 kg of aniline was heat-treated at 220 ° C. for 48 hours with stirring in an autoclave.

  When the obtained nigrosine dye was dried under reduced pressure and analyzed by GC, the amount of aniline A at a GC sample introduction part temperature of 200 ° C. was 0.21%, and the amount of aniline B at a sample introduction part temperature of 260 ° C. was 0.25%. That is, B−A = 0.04%. This nigrosine dye did not ignite after 24 hours in the above pyrophoric test.

Comparative Example 1 ( Example 1 shown in Patent Documents 6 and 7)
Air (500 ml / min) was blown at 75 ° C. for 16 hours while thoroughly stirring the mixture of 1.0 kg of pyrophoric nigrosine and 2.0 kg of aniline used in Example 1. The solution was then dried until the volatile content of aniline or the like was 1% or less, and then cooled.

  When the obtained product was analyzed by GC, the amount of aniline A when the GC sample introduction part temperature was 200 ° C. was 0.51%, and the amount of aniline B when the sample introduction part temperature was 260 ° C. was 0.63%, B−A = 0.12%. In Patent Documents 6 and 7, it is described that the obtained sample is non-ignitable, but it ignited after 6.6 hours according to the above pyrophoric test method.

Comparative Example 2 ( Example 2 shown in Patent Documents 6 and 7)
Air (16 l / min [liter / min]) was blown in at 50 to 55 ° C. for 20 hours while thoroughly stirring the mixture of 1.0 kg of pyrophoric nigrosine and 2.0 kg of aniline used in Example 1. The solution was then dried until the volatile content of aniline or the like was 1% or less, and then cooled.

  When the obtained product was analyzed by GC, the amount of aniline A at a sample introduction part temperature of 200 ° C. was 0.44%, the amount of aniline at a sample introduction part temperature of 260 ° C. was 0.53%, and B−A = It was 0.09%. In Patent Documents 6 and 7, it is described that the obtained sample is non-ignitable, but it ignited after 7.0 hours according to the above pyrophoric test method.

Comparative Example 3
When the same treatment as in Example 1 was performed except that 10 g of hydrochloric acid (pKa = −7.0) was used instead of acetic acid, the amount of aniline A at the sample introduction part temperature of 200 ° C. in the obtained product was 0.47. %, And the sample introduction part temperature 260 ° C., the aniline amount B was 0.78%, that is, B−A = 0.31%. This sample ignited after 3.5 hours.

Comparative Example 4
When the same treatment as in Example 1 was carried out except that 20 g of toluenesulfonic acid (pKa = −6.5) was used instead of acetic acid, the amount of aniline A at the sample introduction part temperature of 200 ° C. in the obtained product was 0. When the sample introduction part temperature was 260 ° C., the aniline amount B was 0.83%, that is, B−A = 0.26%. This sample ignited after 3.2 hours.

Comparative Example 5
When the treatment was carried out in the same manner as in Example 1 except that the reflux treatment time was extremely short (3 hours), the amount of aniline A at the sample introduction part temperature of 200 ° C. in the obtained product was 0.20%. The aniline content B at a part temperature of 260 ° C. was 0.26%, that is, B−A = 0.06%. This sample ignited after 13.5 hours.

Comparative Example 6
When the treatment was carried out in the same manner as in Example 5 except that the reflux treatment time was extremely short (3 hours), the amount of aniline A at the sample introduction part temperature of 200 ° C. in the obtained product was 0.19%. The aniline content B at a part temperature of 260 ° C. was 0.30%, that is, B−A = 0.11%. This sample ignited after 7.0 hours.

Table 1 summarizes the results of Examples and Comparative Examples.

Claims (23)

Using a gas chromatograph apparatus equipped with a glass sample introduction section, the aniline content measured with the sample introduction section temperature set at 200 ° C. was A wt%, and the aniline content measured with the sample introduction section temperature set at 260 ° C. was B wt%. In this case, the nigrosine dye is characterized in that B-A ≦ 0.04% by weight. Contained in a cubic container with a side of 10 cm in accordance with the UN Recommendation “Recommendation for the Transport of Dangerous Goods-Tests and Standards Manual-Revised 3rd Edition (Class 4, Test Method for Self-heating Substances), 140 ° C 2. The nigrosine dye according to claim 1, wherein neither spontaneous ignition nor heat generation of 200 ° C. or more occurs within 24 hours in the test for maintaining the temperature. The nigrosine dye of Claim 1 or 2 obtained by heat-treating the neutralized nigrosine base. The nigrosine dye according to claim 1 or 2, which is obtained by heat-treating a neutralized nigrosine base in a solvent in the presence of an organic acid as a catalyst. The nigrosine dye according to claim 1 or 2, which is obtained by heat-treating a neutralized nigrosine base in a solvent in the presence of a metal oxide as a catalyst. The nigrosine dye according to claim 1 or 2, which is obtained by heat-treating a neutralized nigrosine base in a solvent in the presence of a heteropolyacid as a catalyst. The nigrosine dye of Claim 1 or 2 obtained by heat-treating the neutralized nigrosine base in a solvent without a catalyst. The nigrosine dye according to any one of claims 4 to 7, wherein the solvent is aniline, methylaniline, dimethylaniline, ethylaniline, or diethylaniline . The nigrosine dye according to any one of claims 4 to 7, wherein the solvent is aniline. The nigrosine dye according to claim 4, wherein the pKa of the organic acid is 0 or more. The nigrosine dye according to claim 4, wherein the organic acid has a pKa of 3 to 5. The nigrosine dye according to claim 11, wherein the organic acid is formic acid, succinic acid, acetic acid, propionic acid, butyric acid, benzoic acid, phthalic acid, benzenetricarboxylic acid, or benzenetetracarboxylic acid . The nigrosine dye according to claim 5, wherein the metal oxide is one or more selected from silica, alumina, silica alumina, titania, molybdenum oxide (VI), tungsten oxide (VI), and vanadium oxide (V). . The heteropolyacid is H ₃ PMo ₆ W ₆ O ₄₀ , H ₃ PW ₁₂ O ₄₀ , H ₃ PMo ₁₂ O ₄₀ , H ₃ PMo ₁₀ W ₂ O ₄₀ , H ₃ PMo ₁₀ V ₂ O ₄₀ , H ₄ SiW ₁₂ O _40, and _H 4 _Gemo 12 nigrosine dye according to claim 6, wherein _O is ₄₀ from the selected one or more. The nigrosine dye according to claim 4, wherein the temperature of the heat treatment is 100 ° C or higher and 250 ° C or lower. The nigrosine dye according to claim 5 or 6, wherein the temperature of the heat treatment is 50 ° C or higher and 250 ° C or lower. The nigrosine dye according to claim 7, wherein the temperature of the heat treatment is 200 ° C or higher and 300 ° C or lower. The nigrosine dye according to any one of claims 3 to 7, wherein the heat treatment is performed under pressure. The method for producing a nigrosine dye according to claim 1, wherein the neutralized nigrosine base is subjected to a heat treatment. The method for producing a nigrosine dye according to claim 19, wherein the heat treatment is performed in a solvent. The method for producing a nigrosine dye according to claim 19 or 20, wherein heat treatment is performed in the presence of an organic acid, a metal oxide, or a heteropolyacid as a catalyst. The method for producing a nigrosine dye according to claim 19, 20 or 21, wherein the heat treatment is performed under pressure. The method for producing a nigrosine dye according to claim 20 , wherein the solvent is aniline.